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LIDEM unit for the production of methyl tert-butyl ether from butanes
Rudin, M.G.; Zadvornov, M.A.
One of the basic problems in the production of motor fuels is how to obtain high-octane unleaded gasolines that will meet today`s ecological requirements. The term {open_quotes}reformulated gasolines{close_quotes} has come into general use throughout the world to denote fuels with a certain chemical composition. These gasolines consist of preselected components; as shown by worldwide experience, they must include oxygen-containing compounds that are distinguished by high octane numbers and low reactivities. Standards in effect in the United States, Japan, and certain Western European countries require that automotive gasolines must contain at least 2-4% by weight of oxygen-containing compounds (calculated as oxygen). In the last 15 years, in order to meet these requirements, production has been set up in various countries for the manufacture of high-octane oxygen-containing components known as oxygenates. The most common of these is methyl tert-butyl ether (MTBE), obtained by etherification of isobutene by methanol. Process technology developed by this last organization was used as the basis for constructing a unit in the Nizhnekamskneftekhim Production Association and at the Mazheikyai Petroleum Refinery in Lithuania. MTBE production has been held back mainly by a shortage of isobutene, which is obtained mainly from butane-butene cuts produced in cat crackers. In order to alleviate this shortage, it has been proposed that MTBE should be obtained from saturated C{sub 4} hydrocarbons that are recovered in processing oilfield associated gas, and also in the refinery from primary distillation units, catalytic reformers, and hydrocrackers. A working design was developed in 1991-1992 by Lengiproneftekhim for a basically new combination unit designed for the processing of saturated C{sub 4} hydrocarbons, which has been termed the LIDEM unit (Leningrad - isomerization - dehydrogenation - MTBE).
Accurate Computer Simulation of Phase Equilibrium for Complex Fluid Mixtures. Application to Binaries Involving Isobutene, Methanol, Methyl tert-Butyl Ether, and
Lisal, Martin
to Binaries Involving Isobutene, Methanol, Methyl tert-Butyl Ether, and n-Butane Martin Li´sal,*,, William R + methyl tert-butyl ether (MTBE) and the binaries formed by methanol with isobutene, MTBE, and n
Experimental Pathology Laboratories, Inc. Methyl-Tertiary-Butyl Ether
Baker, Chris I.
Experimental Pathology Laboratories, Inc. Ethyl-Tertiary-Butyl Ether
Baker, Chris I.
State Restrictions on Methyl Tertiary Butyl Ether (released in AEO2006)
Reports and Publications (EIA)
By the end of 2005, 25 states had barred, or passed laws banning, any more than trace levels of methyl tertiary butyl ether (MTBE) in their gasoline supplies, and legislation to ban MTBE was pending in 4 others. Some state laws address only MTBE; others also address ethers such as ethyl tertiary butyl ether (ETBE) and tertiary amyl methyl ether (TAME). Annual Energy Outlook 2006 assumes that all state MTBE bans prohibit the use of all ethers for gasoline blending.
Impacts of Ethanol on Anaerobic Production of Tert-Butyl Alcohol (TBA) from Methyl Tert-Butyl Ether (MTBE) in Groundwater
Scow, K M; MacKay, Douglas
Methyl Tert-Butyl Ether (MTBE) in Groundwater P.I. names,Methyl tert-butyl ether (MTBE) is a contaminant of concernsubsurface environments. MTBE appears to be degraded readily
alkyl tert-butyl ether: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
by Fusarium solani CiteSeer Summary: Fusarium solani degraded methyl tert-butyl ether (MTBE) and other oxygenated compounds from gasoline including tert-butyl alcohol (TBA). The...
Control Study of Ethyl tert-Butyl Ether Reactive Distillation Muhammad A. Al-Arfaj
Al-Arfaj, Muhammad A.
Control Study of Ethyl tert-Butyl Ether Reactive Distillation Muhammad A. Al-Arfaj Department structures for ethyl tert-butyl ether (ETBE) reactive distillation columns are studied. Two process The use of reactive distillation has grown in recent years because it results in less expensive and more
Treatment of Methyl tert-Butyl Ether Vapors in Biotrickling Filters. 2.
vapors of methyl tert-butyl ether (MTBE), a gasoline additive of great environmental concern MTBE treatment are discussed. Introduction The rapidly rising number of reports of groundwater con- taminated with the gasoline additive methyl tert-butyl ether (MTBE) has raised concerns about its
Atmospheric Methyl Tertiary Butyl Ether (MTBE) at a Rural Mountain Site in California
Cohen, Ronald C.
Atmospheric Methyl Tertiary Butyl Ether (MTBE) at a Rural Mountain Site in California Gunnar W. Schade,* Gabrielle B. Dreyfus, and Allen H. Goldstein ABSTRACT (CARB) measured MTBE in urban regions in 1995Â 1996, reporting a range of 0.4 to 13.2 ppbv in the LosMethyl tertiary butyl ether (MTBE
Environmental Microbiology (2001) 3(6), 407416 Methyl tert-butyl ether (MTBE) degradation by a
Environmental Microbiology (2001) 3(6), 407±416 Methyl tert-butyl ether (MTBE) degradation of California, Riverside, Riverside, CA 92521, USA. Summary The widespread use of methyl tert-butyl ether (MTBE is often proposed as the most promising alter- native after treatment. However, MTBE biodegradation appears
Photoionization of methyl t-butyl ether (MTBE) and t-octyl methyl ether (TOME) and analysis of their pyrolyses by
Morton, Thomas Hellman
Photoionization of methyl t-butyl ether (MTBE) and t-octyl methyl ether (TOME) and analysis 1999; accepted 20 July 1999 Abstract The pyrolysis products of neutral methyl-d3 t-butyl ether (MTBE-d3 from thermal cracking patterns. MTBE and TOME both exhibit base peaks at m/z 73 (which shifts to m/z 76
Oxidation of methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE) by ozone and combined ozone/hydrogen peroxide
Leitner, N.K.V.; Papailhou, A.L.; Croue, J.P.; Dore, M. (Univ. de Poitiers (France)); Peyrot, J. (British Petroleum, Harfleur (France))
The aim of this work was to study the reaction of ozone and combined ozone/hydrogen peroxide on oxygenated additives such as methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE) in dilute aqueous solution using controlled experimental conditions. Experiments conducted in a semi-continuous reactor with MTBE and ETBE in combination (initial concentration: 2 mmol/L of each) showed that ETBE was better eliminated than MTBE with both ozone and combined O[sub 3]/H[sub 2]O[sub 2]. batch experiments led to the determination of the ratio of the kinetic constants for the reaction of OH[degree]-radical with MTBE and ETBE (k[sub OH[degree]/ETBE]/k[sub OH[degree]//MTBE] = 1.7). Tert-butyl formate and tert-butyl acetate were identified as the ozonation byproducts of MTBE an ETBE, respectively, while tert-butyl alcohol was found to be produced during the ozonation of both compounds. 10 refs., 10 figs., 1 tab.
IDENTIFYING THE USAGE PATTERNS OF METHYL TERT-BUTYL ETHER (MTBE) AND OTHER OXYGENATES IN GASOLINE 1608 Mt. View Rapid City, SD 57702 Methyl tert-butyl ether (MTBE) is commonly added to gasoline. In 1998, 11.9 billion liters of MTBE were produced in the U.S. MTBE has been detected frequently
Treatment of Methyl tert-Butyl Ether Vapors in Biotrickling Filters. 1.
An aerobic microbial consortium able to biodegrade methyl tert-butyl ether (MTBE) was enriched in two waste, the two laboratory- scale biotrickling filters were able to degrade up to 50 g of MTBE per cubic meter be sustained for at least 4-6 weeks. After the acclimation phase, the MTBE degrading biotrickling filters were
Treatment of Methyl tert-Butyl Ether Contaminated Water Using a Dense
Dandy, David
-butyl ether (MTBE) in a dense medium plasma (DMP) reactor utilizing gas chromatog- raphy-massspectrometryandgaschromatography-thermal conductivity techniques. A rate law is developed for the removal of MTBE from an aqueous solution in the DMP. The oxidation products from the treatment of MTBE-contaminated water in the DMP reactor were found
Enhanced diisobutene production in the presence of methyl tertiary butyl ether
Smith, L.A. Jr.
In the liquid phase reaction of isobutene in the presence of resin cation exchange resins with itself in a C[sub 4] hydrocarbon stream to form dimers, the formation of higher polymers, oligomers, and co-dimer by-products is suppressed by the presence of 0.0001 to 1 mole per mole of isobutene of methyl tertiary butyl ether. 1 fig.
Whole-Genome Analysis of Methyl tert-Butyl Ether-Degrading Beta-Proteobacterium Methylibium petroleiphilum PM1
ethyl-tert butyl ether (ETBE), occurs via a cytochrome P450protein complexes involved in ETBE degradation from R. rubernot been shown to degrade ETBE. Many pollutant degradation
Multiple steady states during reactive distillation of methyl tert-butyl ether
Nijhuis, S.A. (Univ. of Amsterdam (Netherlands). Chemical Engineering Dept.); Kerkhof, F.P.J.M.; Mak, A.N.S. (Comprimo Engineers and Contractors, Amsterdam (Netherlands))
This paper presents results of computer simulations of the synthesis of methyl tert-butyl ether (MTBE) in a fixed-bed reactor and in a reactive distillation column. These calculations clearly showed the advantages of MTBE synthesis in a catalytic distillation tower. Furthermore, the computer simulations showed that multiple steady states may occur in the reactive distillation column during MTBE synthesis in a broad range of operating conditions. An analysis of some sensitivity studies is presented.
Determination of methyl tert. butyl ether (MTBE) in gasoline
Feldman, J.; Orchin, M. (Univ. of Cincinnati, OH (United States))
A GLC-acid extraction method is described for the determination of MTBE in gasolines. The method consists of a programmed GLC analysis starting at about room temperature conducted before and after extraction with cold 85% phosphoric acid. This treatment results in the preferential solubility of ethers and other oxygenated compounds while minimizing the reaction of olefins and aromatics which may be present in the gasolines. Plotting various known concentrations of MTBE in gasolines against the concentrations determined in the same samples by the authors methodology results in a straight line relationship. The concentration of MTBE in any sample of gasoline may thus be determined using their GLC-extraction procedure and the calibration line. The analysis can accommodate a wide choice of standard GLC columns and programs. 2 refs., 1 fig., 1 tab.
Measurement of methyl-tert-butyl-ether (MTBE) in raw drinking water
Davisson, M L; Koester, C J; Moran, J E
In order to assess the pathways for human exposure to methyl-tert-butyl-ether (MTBE) and to understand the extent of MTBE contamination in watersheds, a purge and trap gas chromatographic mass spectrometric method to measure part-per-trillion (ppt) concentrations of MTBE in environmental waters was developed. A variety of California's raw drinking waters were analyzed. No detectable MTBE was found in deep groundwater (>1000 feet). However shallow groundwater ({approx}250 feet) contained MTBE concentrations of non-detect to 1300 ppt. MTBE concentrations measured in rivers and lakes ranged from non-detect to 3500 ppt. East (San Francisco) Bay area rain water contained approximately 80 ppt MTBE.
RELATIONS BETWEEN THE DETECTION OF METHYL TERT-BUTYL ETHER (MTBE) IN SURFACE AND GROUND WATER.S. Geological Survey 1608 Mt. View Rapid City, SD 57702 Methyl tert-butyl ether (MTBE) is commonly used today, the one used most commonly is MTBE. To meet the oxygen requirements of the CAA Amendments, gasoline
Review of the environmental behavior and fate of methyl tert-butyl ether
Squillace, P.J.; Zogorski, J.S. [Geological Survey, Rapid City, SD (United States); Pankow, J.F. [Oregon Graduate Inst. of Science and Technology, Beaverton, OR (United States). Dept. of Environmental Science and Engineering; Korte, N.E. [Oak Ridge National Lab., TN (United States). Environmental Science Div.
A review of pertinent equations and current research indicates that when gasoline oxygenated with methyl tert-butyl ether (MTBE) comes into contact with water, large amounts of MTBe can dissolve. At 25 C, the water solubility of MTBE is about 5,000 mg/L for a gasoline that is 10% MTBE by weight, whereas for a nonoxygenated gasoline, the total hydrocarbon solubility in water is typically about 120 mg/L. Methyl tert-butyl ether sorbs only weakly to subsurface solids; therefore, sorption does not substantially retard the transport of MTBE by ground water. In addition, MTBE generally resists biodegradation in ground water. The half-life of MTBE in the atmosphere can be as short as 3 d in a regional airshed. In the air, MTBE tends to partition into atmospheric water, including precipitation. However, the washing out of gas-phase MTBE by precipitation will not, by itself, greatly alter the gas-phase concentration of the compound in the air. The partitioning of MTBE to precipitation can nevertheless result in concentrations as high as 3 {micro}g/L or more in urban precipitation and can contribute to the presence of MTBE in surface and ground water.
Observation on the biodegradation and bioremediation potential of methyl t-butyl ether
Salanitro, J.; Wisniewski, H.; McAllister, P. [Shell Development Co., Houston, TX (United States)
There have been few reports documenting evidence for the biodegradation of the fuel oxygenate alkyl ether, methyl t-butyl ether (MTBE) in groundwater, soils, and biosludges. Partial (or complete) microbial breakdown of MTBE has been observed in an anaerobic subsoil, a river sediment under methanogenic conditions, a cyclohexane-degrading bacterial consortium and a pure culture of the methylotroph, Methylisnus trichosporium OB3b. An aerobic bacterial enrichment (BC-1) isolated from an industrial transient (non-accumulating) metabolic intermediate. The studies suggest that MTBE is cleaved by BC-1 to TBA which is then metabolized via isopropanol and acetone. There is little information on the occurrence of indigenous MTBE-degraders in groundwater, soils and activated sludges. Preliminary evidence has been obtained, however, from a marketing terminal groundwater site that naturally-occurring MTBE-degraders are present in some monitoring wells. Microcosm experiments with groundwater from this aquifer show that MTBE is aerobically degraded (no TBA formed) with a first-order decay rate (0.31/day) similar to BTEX. Also, MTBE did not inhibit the intrinsic biodegradation potential of BTEX in groundwater microcosms. In summary, the data presented indicate that MTBE biodegradation has been observed in some environmental media. Further work is needed to assess the feasibility of using indigenous or derived aerobic and anaerobic MTBE-degrading cultures for treating fuel ethers in groundwaters or wastewater with in-situ or ex-situ bioremediation technologies.
Treatment of methyl t-butyl ether contaminated water using a dense medium plasma reactor, a mechanistic and kinetic investigation
Dandy, David
and oxidation mechanisms of methyl t-butyl ether (MTBE) in a dense medium plasma (DMP) reactor utilizing gas for the removal of MTBE from an aqueous solution in the DMP reactor. Rate constants are also derived for three reactor configurations and two pin array spin rates. The oxidation products from the treatment of MTBE
Why methyl tert-butyl ether production by reactive distillation may yield multiple solutions
Hauan, S.; Hertzberg, T.; Lien, K.M. [Univ. of Trondheim (Norway)
This paper presents an explanation of why methyl tert-butyl ether (MTBE) production by reactive distillation may yield multiple solutions. Widely different composition profiles and conversions may, as already reported by Krishna and others, results with identical column specifications, depending on the initial estimates provided. A hypothesis yielding a qualitative understanding of this phenomenon has been developed. The inert n-butene plays a key role in the proposed explanation: As the reaction mixture is diluted with n-butene, the activity coefficient of methanol increases substantially and the temperature decreases. This dilution has a profound effect on the equilibrium conversion, enabling MTBE to escape from the reactive zone without decomposition. When methanol is fed below or in the lower part of the reactive zone of the column, the ``lifting capacity`` of the minimum boiling point MTBE-methanol azeotrope will also be important.
Acute toxicity of methyl-tertiary-butyl ether (MTBE) to aquatic organisms
BenKinney, M.T.; Barbieri, J.F.; Gross, J.S.; Naro, P.A. [Stonybrook Labs. Inc., Princeton, NJ (United States)
Due to the recent amendment of the Clean Air Act, oxygenates are now being added to gasolines to boost octane and reduce air pollution from combustion in heavily populated areas. Oxygenates such as alcohols (i.e. methanol) and ethers (methyl-tertiary-butyl ether, MTBE) are commonly being used. A series of bioassay studies have been conducted with MTBE, one of the most commonly used octane-enhancing additives. Freshwater and marine studies were conducted with fish, invertebrates and algae to determine the impact of this material on the environment following accidental spills. Static-renewal studies were run to ensure maintenance of MTBE, a highly volatile material in the test containers. Chemical confirmation of exposure concentrations demonstrated the adequacy of the exposure system. Mysid shrimp were highly sensitive to MTBE, with significantly less effect observed with the other species evaluated. These data have implications for spill response, particularly since MTBE is slow to biodegrade and will rapidly move through groundwater. Comparative data for other oxygenates will also be discussed.
Exposure to methyl tert-butyl ether and benzene among service station attendants and operators
Hartle, R. [National Inst. for Occupational Safety and Health, Cincinnati, OH (United States)
Concerns for atmospheric pollution from auto exhaust have led to the blending of {open_quotes}oxygenates{close_quotes} with motor fuels. The most common oxygenate, methyl tert-butyl ether (MTBE) is currently required within several metropolitan areas (Denver and Phoenix) in the range of 12% of the motor fuel. Amendments to the Clean Air Act may expand this requirement to as many as 44 other areas of the United States in the near future. In consideration of the magnitude of potential uncontrolled exposures from its extensive use and a related concern involving the potential influence of MTBE blending on exposures to other constituents of gasoline (particularly benzene), an evaluation of exposures among service station attendants and operators was undertaken at the request, and in cooperation with, the American Petroleum Institute during the latter part of 1990. For application of the survey results to a broad audience, three categories or types of service stations were identified with regard to MTBE use and exposure potential: (a) service stations that do not use MTBE or use it only as an octane enhancer, (b) service stations with seasonal requirements to use 12-15% MTBE (the Denver, Colorado, and Phoenix, Arizona, metropolitan areas), and (c) service stations equipped with stage II (active) vapor recovery systems (several coastal areas, most notably Southern California). 4 refs., 4 tabs.
Toxicity of methyl tertiary butyl ether to Daphnia magna and photobacterium phosphoreum
Gupta, G.; Lin, Y.J. [Univ. of Maryland Eastern Shore, Princess Anne, MD (United States)
Methyl tertiary butyl ether (MTBE) is a liquid organic compound added to gasoline to increase its oxygen content and to reduce the emission of carbon monoxide during combustion in many urban areas. In order to meet the 1990 Clean Air Act amendments, gasoline must contain 2.7% oxygen (by weight) or 15% (by volume) of MTBE in gasoline to meet the regulations for the control of carbon monoxide emissions. Health effects caused by inhalation of MTBE include headaches, dizziness, irritated eyes and nausea; MTBE is one of cancer--causing chemicals. Intracaval injection of MTBE (0.2 mg/kg) caused the highest mortality (100%) in rats. General anesthetic effect induced by MTBE was found at or above 1200 mg/kg body weight; Rosenkranz and Klopman (1991) predicted that MTBE is neither a genotoxicant nor a carcinogen. Nevertheless, the safety of using MTBE in oxygenated fuels is now being questioned from its potential as groundwater pollutant. This study measures the toxicity of MTBE to Daphnia magna and Photobacterium phosphoreum. 13 refs.
Reaction calorimetry study of the liquid-phase synthesis of tert-butyl methyl ether
Sola, L.; Pericas, M.A.; Cunill, F.; Iborra, M. (Univ. de Barcelona (Spain). Dept. d'Enginyeria Quimica)
The liquid-phase addition of methanol to isobutene to give tert-butyl methyl ether (MTBE) on the ion-exchange resin Lewatit K2631 has been studied in a calorimetric reactor. Heat capacity of MTBE and enthalpy of the MTBE synthesis reaction in the temperature range 312--333 K have been determined. MTBE heat capacity in the liquid phase has been found to obey the equation c[sub P] (J/mol[center dot]K) = 472.34 [minus] 2.468(T/K) + 0.005071(T/K)[sup 2]. At 298 K the standard molar reaction enthalpy is [Delta]H[degree] = [minus]33.8 kJ/mol. A method to estimate apparent activation energies from heat flow rate in a given reaction has been developed and proved to be valid for the MTBE synthesis. Using this method, an apparent activation energy of 91.1--95.2 kJ/mol is calculated. A [minus]3.8 kJ/mol value has been found for the adsorption enthalpy of methanol on the ion-exchange resin Lewatit K2631 by a combination of reaction calorimetry and thermogravimetry. This allows the calculation of an activation energy on the gel phase of the resin of 91 kJ/mol.
Disposition, metabolism, and toxicity of methyl tertiary butyl ether, an oxygenate for reformulated gasoline
Hutcheon, D.E.; Hove, W. ten; Boyle, J. III [UMDNJ, New Jersey Medical Schook, Newark, NJ (United States)] [UMDNJ, New Jersey Medical Schook, Newark, NJ (United States); Arnold, J.D. [Arnold & Arnold, Inc., Kansas City, MO (United States)] [Arnold & Arnold, Inc., Kansas City, MO (United States)
Studies of the toxicology of methyl tertiary butyl ether (MTBE) were reviewed as a possible information base for evaluating the health effects of evaporative emissions from reformulated gasoline (RFG). Perirenal fat/blood MTBE concentration ratios ranged from 9.7 to 11.6 after 15 wk of intermittent exposure. During an oxyfuels program in Fairbanks, AK, blood levels of occupationally exposed workers were 0.2-31.5 {mu}g/L MTBE and 1.6 to 72.2 {mu}g/L TBA with a mean TBA:MTBE blood concentration ratio of 4.2. In patients who received MTBE by percutaneous, transhepatic puncture for the dissolution of cholesterol gallstones, concentrations of MTBE in fat tissue reached 60 and 300 {mu}g/g at a treatment time when mean blood MTBE was less than 20 {mu}g/ml. The results of laboratory and clinical studies indicate that metabolites of MTBE may contribute to the nephropathy, neoplasms, and other pathological changes associated with repeated exposure to MTBE in experimental animals. It is concluded that such studies can provide a well-defined database for quantitatitive safety comparisons and health risk-benefit analyses of MTBE and other oxygenates in RFG. 39 refs., 1 tab.
Ethyl-tertiary-butyl-ether (ETBE) as an aviation fuel: Eleventh international symposium on alcohol fuels
Maben, G.D.; Shauck, M.E.; Zanin, M.G.
This paper discusses the preliminary flight testing of an aircraft using neat burning ethyl-tertiary-butyl-ether (ETBE) as a fuel. No additional changes were made to the fuel delivery systems which had previously been modified to provide the higher fuel flow rates required to operate the engine on neat ethanol. Air-fuel ratios were manually adjusted with the mixture control. This system allows the pilot to adjust the mixture to compensate for changes in air density caused by altitude, pressure and temperature. The engine was instrumented to measure exhaust gas temperatures (EGT), cylinder head temperatures (CHT), and fuel flows, while the standard aircraft instruments were used to collect aircraft performance data. Baseline engine data for ETBE and Avgas are compared. Preliminary data indicates the technical and economic feasibility of using ETBE as an aviation fuel for the piston engine fleet. Furthermore, the energy density of ETBE qualifies it as a candidate for a turbine engine fuel of which 16.2 billion gallons are used in the US each year.
Biodegradation of methyl tert-butyl ether by a bacterial pure culture
Hanson, J.R.; Ackerman, C.E.; Scow, K.M.
A bacterial strain, PM1, which is able to utilize methyl tert-butyl ether (MTBE) as its sole carbon and energy source, was isolated from a mixed microbial consortium in a compost biofilter capable of degrading MTBE. Initial linear rates of MTBE degradation by 2 x 10{sup 6} cells ml{sup {minus}1} were 0.07, 1.17, and 3.56 {mu}g ml{sup {minus}1} h{sup {minus}1} for initial concentrations of 5, 50, and 500 {mu}g MTBE ml{sup {minus}1}, respectively. When incubated with 20 {mu}g of uniformly labeled [{sup 14}C]MTBE ml{sup {minus}1}, strain PM1 converted 46% to {sup 14}CO{sub 2} and 19% to {sup 14}C-labeled cells within 120 h. This yield is consistent with the measurement of protein accumulation at different MTBE concentrations from which was estimated a biomass yield of 0.18 of cells mg MTBE{sup {minus}1}. Strain PM1 was inoculated into sediment core material collected from a contaminated groundwater plume at Port Hueneme, California, in which there was no evidence of MTBE degradation. Strain PM1 readily degraded 20 {micro}g of MTBE ml{sup {minus}1} added to the core material. The rate of MTBE removal increased with additional inputs of 20 {micro}g of MTBE ml{sup {minus}1}. These results suggest that PM1 has potential for use in the remediation of MTBE-contaminated environments.
Methyl tert-butyl ether (MTBE) is a volatile organic com-pound (VOC) derived from natural gas that is added to gas-
Methyl tert-butyl ether (MTBE) is a volatile organic com- pound (VOC) derived from natural gas Water in Urban and Agricultural Areas made from methanol, which is derived primarily from natural gas that is added to gas- oline either seasonally or year round in many parts of the United States to increase
Kinetics and modeling of mixture effects during complete catalytic oxidation of benzene and methyl tert-butyl ether
Dangi, S.; Abraham, M.A. [Univ. of Tulsa, OK (United States). Dept. of Chemical Engineering] [Univ. of Tulsa, OK (United States). Dept. of Chemical Engineering
The performance of a catalytic incinerator depends on the nature of the compounds being oxidized and cannot be predicted simply by knowing the performance of the incinerator with pure-component model compounds. Considering the importance of mixture effects, an attempt was made to develop a combined model to predict the conversion when benzene and methyl tert-butyl ether (MTBE) are simultaneously oxidized. Complete catalytic oxidation of benzene and MTBE, singly and in mixtures, was investigated over a platinum catalyst. No inhibition effects were seen with benzene, but MTBE conversion was distinctly inhibited by benzene. A Mars-van Krevelen rate model was used to explain the results. Model parameters were obtained from pure-component experiments and then incorporated into a multicomponent model without any adjustment or additional rate parameters. The multicomponent model was able to predict the conversion of benzene and MTBE oxidation in the binary mixture using the pure-component data without adjustable parameters.
Synthesis of octane enhancers during slurry-phase Fischer-Tropsch. [801Methyl tert-butyl ether
Marcelin, G.
The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl ether (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: (1) Addition of isobutylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch. (2) Addition of isobutylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst. (3) Addition of methanol to slurry phase FT synthesis making iso-olefins. During the sixth quarter we completed the construction of the slurry bubble column reactor (SBCR), conducted initial shake-down experiments in a cold-flow mode, and finalized the selection process of the acid catalysts for conversion of syngas-produced alcohols and isobutylene to MTBE (scheme 2). Tasks 3, 4, and 5 are awaiting complete implementation of the SBCR system.
Alveolar breath sampling and analysis to assess exposures to methyl tertiary butyl ether (MTBE) during motor vehicle refueling
Lindstrom, A.B.; Pleil, J.D. [U.S. Environmental Protection Agency, Research Triangle Park, NC (United States)
In this study we present a sampling and analytical methodology that can be used to assess consumers` exposures to methyl tertiary butyl ether (MTBE) that may result from routine vehicle refueling operations. The method is based on the collection of alveolar breath samples using evacuated one-liter stainless steel canisters and analysis using a gas chromatograph-mass spectrometer equipped with a patented `valveless` cryogenic preconcentrator. To demonstrate the utility of this approach, a series of breath samples was collected from two individuals (the person pumping the fuel and a nearby observer) immediately before and for 64 min after a vehicle was refueled with premium grade gasoline. Results demonstrate low levels of MTBE in both subjects` breaths before refueling, and levels that increased by a factor of 35 to 100 after the exposure. Breath elimination models fitted to the post exposure measurements indicate that the half-life of MTBE in the first physiological compartment was between 1.3 and 2.9 min. Analysis of the resulting models suggests that breath elimination of MTBE during the 64 min monitoring period was approximately 155 {mu}g for the refueling subject while it was only 30 {mu}g for the nearby observer. This analysis also shows that the post exposure breath elimination of other gasoline constituents was consistent with previously published observations. 20 refs., 3 figs., 4 tabs.
Whole-genorne analysis of the methyl tert-butyl ether-degrading beta-proteobacterium Methylibium petroleiphilum PM1
Kane, Staci R. [Lawrence Livermore National Laboratory (LLNL); Chakicherla, Anu Y. [Lawrence Livermore National Laboratory (LLNL); Chain, Patrick S. G. [Lawrence Livermore National Laboratory (LLNL); Schmidt, Radomir [University of California, Davis; Shin, M [U.S. Department of Energy, Joint Genome Institute; Legler, Tina C. [Lawrence Livermore National Laboratory (LLNL); Scow, Kate M. [University of California, Davis; Larimer, Frank W [ORNL; Lucas, Susan [Joint Genome Institute, Walnut Creek, California; Richardson, P M [U.S. Department of Energy, Joint Genome Institute; Hristova, Krassimira R. [University of California, Davis
Methylibium petroleiphilum PM1 is a methylotroph distinguished by its ability to completely metabolize the fuel oxygenate methyl tert-butyl ether (MTBE). Strain PM1 also degrades aromatic (benzene, toluene, and xylene) and straight-chain (C, to C,,) hydrocarbons present in petroleum products. Whole-genome analysis of PM1 revealed an similar to 4-Mb circular chromosome and an similar to 600-kb megaplasmid, containing 3,831 and 646 genes, respectively. Aromatic hydrocarbon and alkane degradation, metal resistance, and methylotrophy are encoded on the chromosome. The megaplasmid contains an unusual t-RNA island, numerous insertion sequences, and large repeated elements, including a 40-kb region also present on the chromosome and a 29-kb tandem repeat encoding phosphonate transport and cobalamin biosynthesis. The megaplasmid also codes for alkane degradation and was shown to play an essential role in MTBE degradation through plasmid-curing experiments. Discrepancies between the insertion sequence element distribution patterns, the distributions of best BLASTP hits among major phylogenetic groups, and the G+C contents of the chromosome (69.2%) and plasmid (66%), together with comparative genome hybridization experiments, suggest that the plasmid was recently acquired and apparently carries the genetic information responsible for PM1's ability to degrade MTBE. Comparative genomic hybridization analysis with two PM1-like MTBE-degrading environmental isolates (similar to 99% identical 16S rRNA gene sequences) showed that the plasmid was highly conserved (ca. 99% identical), whereas the chromosomes were too diverse to conduct resequencing analysis. PM1's genome sequence provides a foundation for investigating MTBE biodegradation and exploring the genetic regulation of multiple biodegradation pathways in M. petroleiphilum and other MTBE-degrading beta-proteobacteria.
Exposure to methyl tert-butyl ether, benzene, and total hydrocarbons at the Singapore-Malaysia causeway immigration checkpoint
Tan, C.; Ong, H.Y.; Kok, P.W. [and others
The primary aim of this study was to determine the extent and levels of exposure to volatile organic compounds (VOCs) from automobile emissions in a group of immigration officers at a busy cross-border checkpoint. A majority (80%) of the workers monitored were exposed to benzene at levels between 0.01 and 0.5 ppm, with only 1.2% exceeding the current Occupational Safety and Health Administration occupational exposure limit of 1 ppm. The geometric mean (GM) concentrations of 8-hr time-weighted average exposure were 0.03 ppm, 0.9 ppm, and 2.46 ppm for methyl-tert-butyl ether (MTBE), benzene, and total hydrocarbons (THC), respectively. The highest time-weighted average concentrations measured were 1.05 ppm for MTBE, 2.01 ppm for benzene, and 34 ppm for THC. It was found that motorbikes emitted a more significant amount of pollutants compared with motor cars. On average, officers at the motorcycle booths were exposed to four to five times higher levels of VOCs (GMs of 0.07 ppm, 0.23 ppm, and 4.7 ppm for MTBE, benzene, and THC) than their counterparts at the motor car booths (GMs of 0.01 ppm, 0.05 ppm, and 1.5 ppm). The airborne concentrations of all three pollutants correlated with the flow of vehicle traffic. Close correlations were also noted for the concentrations in ambient air for the three pollutants measured. Benzene and MTBE had a correlation coefficient of 0.97. The overall findings showed that the concentrations of various VOCs were closely related to the traffic density, suggesting that they were from a common source, such as exhaust emissions from the vehicles. The results also indicated that although benzene, MTBE, and THC are known to be volatile, a significant amount could still be detected in the ambient environment, thus contributing to our exposure to these compounds. 4 refs., 6 figs.
Manipulation of the HIF–Vegf pathway rescues methyl tert-butyl ether (MTBE)-induced vascular lesions
Bonventre, Josephine A., E-mail: email@example.com [Rutgers, The State University of New Jersey, Joint Graduate Program in Toxicology, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Rutgers, The State University of New Jersey, Department of Biochemistry and Microbiology, 76 Lipman Dr., New Brunswick, NJ 08901 (United States); Oregon State University, Department of Environmental and Molecular Toxicology, 1011 Agricultural and Life Sciences Bldg, Corvallis, OR 97331 (United States); Kung, Tiffany S., E-mail: email@example.com [Rutgers, The State University of New Jersey, Joint Graduate Program in Toxicology, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Rutgers, The State University of New Jersey, Department of Biochemistry and Microbiology, 76 Lipman Dr., New Brunswick, NJ 08901 (United States); White, Lori A., E-mail: firstname.lastname@example.com [Rutgers, The State University of New Jersey, Joint Graduate Program in Toxicology, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Rutgers, The State University of New Jersey, Department of Biochemistry and Microbiology, 76 Lipman Dr., New Brunswick, NJ 08901 (United States); Cooper, Keith R., E-mail: firstname.lastname@example.com [Rutgers, The State University of New Jersey, Joint Graduate Program in Toxicology, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Rutgers, The State University of New Jersey, Department of Biochemistry and Microbiology, 76 Lipman Dr., New Brunswick, NJ 08901 (United States)
Methyl tert-butyl ether (MTBE) has been shown to be specifically anti-angiogenic in piscine and mammalian model systems at concentrations that appear non-toxic in other organ systems. The mechanism by which MTBE targets developing vascular structures is unknown. A global transcriptome analysis of zebrafish embryos developmentally exposed to 0.00625–5 mM MTBE suggested that hypoxia inducible factor (HIF)-regulated pathways were affected. HIF-driven angiogenesis via vascular endothelial growth factor (vegf) is essential to the developing vasculature of an embryo. Three rescue studies were designed to rescue MTBE-induced vascular lesions: pooled blood in the common cardinal vein (CCV), cranial hemorrhages (CH), and abnormal intersegmental vessels (ISV), and test the hypothesis that MTBE toxicity was HIF–Vegf dependent. First, zebrafish vegf-a over-expression via plasmid injection, resulted in significantly fewer CH and ISV lesions, 46 and 35% respectively, in embryos exposed to 10 mM MTBE. Then HIF degradation was inhibited in two ways. Chemical rescue by N-oxaloylglycine significantly reduced CCV and CH lesions by 30 and 32% in 10 mM exposed embryos, and ISV lesions were reduced 24% in 5 mM exposed zebrafish. Finally, a morpholino designed to knock-down ubiquitin associated von Hippel–Lindau protein, significantly reduced CCV lesions by 35% in 10 mM exposed embryos. In addition, expression of some angiogenesis related genes altered by MTBE exposure were rescued. These studies demonstrated that MTBE vascular toxicity is mediated by a down regulation of HIF–Vegf driven angiogenesis. The selective toxicity of MTBE toward developing vasculature makes it a potentially useful chemical in the designing of new drugs or in elucidating roles for specific angiogenic proteins in future studies of vascular development. - Highlights: • Global gene expression of MTBE exposed zebrafish suggested altered HIF1 signaling. • Over expression of zebrafish vegf-a rescues MTBE-induced vascular lesions. • Inhibiting PHD or knocking down VHL rescues MTBE-induced vascular lesions. • HIF1-Vegf driven angiogenesis is a target for MTBE vascular toxicity.
Kinetics and mechanism of the sonolytic destruction of methyl tert-butyl ether by ultrasonic irradiation in the presence of ozone
Kang, J.W. [Yonsei Univ., Wonju (Korea, Republic of). Dept. of Industrial Environment and Health] [Yonsei Univ., Wonju (Korea, Republic of). Dept. of Industrial Environment and Health; Hoffmann, M.R. [California Inst. of Tech., Pasadena, CA (United States). W.M. Keck Labs.] [California Inst. of Tech., Pasadena, CA (United States). W.M. Keck Labs.
The kinetics and mechanism of the sonolytic degradation of methyl tert-butyl ether (MTBE) have been investigated at an ultrasonic frequency of 205 kHz and power of 200 W L{sup {minus}1}. The observed first-order degradation rate constant for the loss of MTBE increased from 4.1 {times} 10{sup {minus}4} s{sup {minus}1} to 8.5 {times} 10{sup {minus}4} s{sup {minus}1} as the concentration of MTBE decreased from 1.0 to 0.01 mM. In the presence of O{sub 3}, the sonolytic rate of destruction of MTBE was accelerated substantially. The rate of MTBE sonolysis with ozone was enhanced by a factor of 1.5--3.9 depending on the initial concentration of MTBE. tert-Butyl formate, tert-butyl alcohol, methyl acetate, and acetone were found to be the primary intermediates and byproducts of the degradation reaction with yields of 8, 5, 3, and 12%, respectively. A reaction mechanism involving three parallel pathways that include the direct pyrolytic decomposition of MTBE, the direct reaction of MTBE with ozone, and the reaction of MTBE with hydroxyl radical is proposed.
anhydride-vinyl methyl ether: Topics by E-print Network
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TREAT METHYL- TERT-BUTYL ETHER CONTAMINATED CiteSeer Summary: Methyl-tert-butyl ether (MTBE) is a commonly used gasoline additive. Leaking underground storage tank systems,...
alkyl-tert alkyl ethers: Topics by E-print Network
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TREAT METHYL- TERT-BUTYL ETHER CONTAMINATED CiteSeer Summary: Methyl-tert-butyl ether (MTBE) is a commonly used gasoline additive. Leaking underground storage tank systems,...
Treatment of methyl tert-butyl ether vapors in a biotrickling filters. 2. Analysis of the rate-limiting step and behavior under transient conditions
Fortin, N.Y.; Deshusses, M.A. [Univ. of California, Riverside, CA (United States). Dept. of Chemical and Environmental Engineering] [Univ. of California, Riverside, CA (United States). Dept. of Chemical and Environmental Engineering
Detailed experiments were performed with gas phase biotrickling filters treating vapors of methyl tert-butyl ether (MTBE), a gasoline additive of great environmental concern. A particular emphasis was placed on the analysis of the rate-limiting step, and it was found that the process was mostly limited by the biological reaction rather than by mass transfer. Further experiments involved the study of the dynamic behavior of the biotrickling filters under simulated field conditions. In all cases, the biotrickling filters adapted rapidly to the new conditions, and new steady states were obtained within hours. The relevance of the results and the implications as far as implementation of biotrickling filters for field MTBE treatment are discussed.
Cytotoxic and DNA-damaging effects of methyl tert-butyl ether and its metabolites on HL-60 cells in vitro
Tang, G.H. [Xian Medical Univ. (China); Shen, Y.; Shen, H.M. [National Univ. of Singapore (Singapore)] [and others
Methyl tert-butyl ether (MTBE) is a widely used oxygenate in unleaded gasoline; however, few studies have been conducted on the toxicity of this compound. This study evaluates the cytotoxic and DNA-damaging effects of MTBE and its metabolites in a human haemopoietic cell line, HL-60. The metabolites of MTBE studied include tertiary butyl alcohol (TBA), {alpha}-hydroxyisobutyric acid (HIBA), and formaldehyde. Comet assay is used to assess DNA damage, and the cytotoxicity is investigated by lactate dehydrogenease (LDH) release. The results show no significant cytotoxic effects of MTBE, TBA, and HIBA over a concentration ranging from 1 to 30 mM. Formaldehyde, in contrast, causes a substantial LDH release at a concentration of 5 {mu}M. Hydrogen peroxide, a known oxidative agent, at concentrations ranging from 10 to 100 {mu}M, produces a significant dose-related increase in DNA damage, whereas a much higher concentration of MTBE (1 to 30 mM) is required to produce a similar observation. The genotoxic effects of TBA and HIBA appear to be identical to that of MTBE. Conversely, DNA damage is observed for formaldehyde at a relatively low concentration range (5 to 100 {mu}M). These findings suggest that MTBE and its metabolites, except formaldehyde, have relatively low cytotoxic and genotoxic effects. 16 refs., 4 figs.
Determination of Methyl tert-Butyl Ether and tert-Butyl Alcohol in Water by Solid-Phase Microextraction/Head Space Analysis in Comparison to EPA Method 5030/8260B
Oh, Keun-Chan; Stringfellow, William T.
Methyl tert-butyl ether (MTBE) is now one of the most common groundwater contaminants in the United States. Groundwater contaminated with MTBE is also likely to be contaminated with tert-butyl alcohol (TBA), because TBA is a component of commercial grade MTBE, TBA can also be used as a fuel oxygenate, and TBA is a biodegradation product of MTBE. In California, MTBE is subject to reporting at concentrations greater than 3 {micro}g/L. TBA is classified as a ''contaminant of current interest'' and has a drinking water action level of 12 {micro}g/L. In this paper, we describe the development and optimization of a simple, automated solid phase microextraction (SPME) method for the analysis of MTBE and TBA in water and demonstrate the applicability of this method for monitoring MTBE and TBA contamination in groundwater, drinking water, and surface water. In this method, the headspace (HS) of a water sample is extracted with a carboxen/polydimethylsiloxane SPME fiber, the MTBE and TBA are desorbed into a gas chromatograph (GC), and detected using mass spectrometry (MS). The method is optimized for the routine analysis of MTBE and TBA with a level of quantitation of 0.3 {micro}g/L and 4 {micro}g/L, respectively, in water. MTBE quantitation was linear for over two orders of concentration (0.3 {micro}g/L -80 {micro}g/L). TBA was found to be linear within the range of 4 {micro}g/L-7,900 {micro}g/L. The lower level of detection for MTBE is 0.03 {micro}g/L using this method. This SPME method using headspace extraction was found to be advantageous over SPME methods requiring immersion of the fiber into the water samples, because it prolonged the life of the fiber by up to 400 sample analyses. This is the first time headspace extraction SPME has been shown to be applicable to the measurement of both MTBE and TBA at concentrations below regulatory action levels. This method was compared with the certified EPA Method 5030/8260B (purge-and-trap/GC/MS) using split samples from laboratory bioreactors treating MTBE contaminated water and applied to environmental samples collected throughout the East Bay area of California. Results from the SPME-HS/GC/MS method were directly comparable to the EPA Method 5030/8260B. This method provides an simple, inexpensive, accurate, and sensitive alternative to EPA Method 5030/8260B for the analysis of MTBE and TBA in water samples.
Treatment of methyl tert-butyl ether vapors in biotrickling filters. 1. Reactor startup, steady-state performance, and culture characteristics
Fortin, N.Y.; Deshusses, M.A. [Univ. of California, Riverside, CA (United States). Dept. of Chemical and Environmental Engineering] [Univ. of California, Riverside, CA (United States). Dept. of Chemical and Environmental Engineering
An aerobic microbial consortium able to biodegrade methyl tert-butyl ether (MTBE) was enriched in two waste air biotrickling filters after continuous operation for 6 months. After this acclimation phase, the two laboratory-scale biotrickling filters were able to degrade up to 50 g of MTBE per cubic meter of reactor per hour, a value comparable to other gasoline constituents. Such high performance could be sustained for at least 4--6 weeks. After the acclimation phase, the MTBE degrading biotrickling filters were characterized by their almost full conversion of MTBE to carbon dioxide and the absence of any degradation byproducts in either the gas or the liquid phase. They also exhibited a very high specific degradation activity per amount of biomass, and a low rate of biomass accumulation. An observed biomass yield of 0.1 g g{sup {minus}1} and a specific growth rate of 0.025 day{sup {minus}1} were determined for the biotrickling filter process culture. Further data on MTBE mass transfer and on the dynamic behavior of the biotrickling filter are presented in part 2 of this paper. Overall, the results demonstrate that MTBE can be effectively biodegraded under carefully controlled environmental conditions.
Effect of Ethanol and Methyl-tert-Butyl Ether on Monoaromatic Hydrocarbon Biodegradation: Response Variability for Different Aquifer Materials Under Various Electron-Accepting Conditions
Ruiz-Aguilar, G L; Fernandez-Sanchez, J M; Kane, S R; Kim, D; Alvarez, P J
Aquifer microcosms were used to determine how ethanol and methyl-tert-butyl ether (MtBE) affect monoaromatic hydrocarbon degradation under different electron-accepting conditions commonly found in contaminated sites experiencing natural attenuation. Response variability was investigated by using aquifer material from four sites with different exposure history. The lag phase prior to BTEX (benzene, toluene, ethylbenzene, and xylenes) and ethanol degradation was typically shorter in microcosms with previously contaminated aquifer material, although previous exposure did not always result in high degradation activity. Toluene was degraded in all aquifer materials and generally under a broader range of electron-accepting conditions compared to benzene, which was degraded only under aerobic conditions. MtBE was not degraded within 100 days under any condition, and it did not affect BTEX or ethanol degradation patterns. Ethanol was often degraded before BTEX compounds, and had a variable effect on BTEX degradation as a function of electron-accepting conditions and aquifer material source. An occasional enhancement of toluene degradation by ethanol occurred in denitrifying microcosms with unlimited nitrate; this may be attributable to the fortuitous growth of toluene-degrading bacteria during ethanol degradation. Nevertheless, experiments with flow-through aquifer columns showed that this beneficial effect could be eclipsed by an ethanol-driven depletion of electron acceptors, which significantly inhibited BTEX degradation and is probably the most important mechanism by which ethanol could hinder BTEX natural attenuation. A decrease in natural attenuation could increase the likelihood that BTEX compounds reach a receptor as well as the potential duration of exposure.
The Effect of the Di-Tertiary Butyl Peroxide (DTBP) additive on HCCI Combustion of Fuel Blends of Ethanol and Diethyl Ether
Mack, John Hunter; Buchholz, Bruce A; Flowers, Daniel L; Dibble, Robert W
diethyl ether (DEE) in ethanol fuel blends for a range ofbio-derived fuel components (ethanol) in emission productsHCCI Combustion of Fuel Blends of Ethanol and Diethyl Ether
antioxidant butylated hydroxytoluene: Topics by E-print Network
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by Fusarium solani CiteSeer Summary: Fusarium solani degraded methyl tert-butyl ether (MTBE) and other oxygenated compounds from gasoline including tert-butyl alcohol (TBA). The...
ammoniated glycyrrhizin butylated: Topics by E-print Network
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by Fusarium solani CiteSeer Summary: Fusarium solani degraded methyl tert-butyl ether (MTBE) and other oxygenated compounds from gasoline including tert-butyl alcohol (TBA). The...
Sonolytic destruction of methyl tert-butyl ether by ultrasonic irradiation: The role of O{sub 3}, H{sub 2}O{sub 2}, frequency, and power density
Kang, J.W.; Hung, H.M.; Lin, A.; Hoffmann, M.R. [California Inst. of Tech., Pasadena, CA (United States). W.M. Keck Labs.] [California Inst. of Tech., Pasadena, CA (United States). W.M. Keck Labs.
The kinetics of degradation of methyl tert-butyl ether (MTBE) by ultrasonic irradiation in the presence of ozone as functions of applied frequencies and applied power are investigated. Experiments are performed over the frequency range of 205--1,078 kHz. The higher overall reaction rates are observed at 358 and 618 kHz and then at 205 and 1,078 kHz. The observed pseudo-first-order rate constant, k{sub 0}, for MTBE degradation increases with increasing power density up to 250 W L{sup {minus}1}. A linear dependence of the first-order rate constant, k{sub O{sub 3}}, for the simultaneous degradation of O{sub 3} on power density is also observed. Naturally occurring organic matter (NOM) is shown to have a negligible effect on observed reaction rates.
active methyl tert-butyl: Topics by E-print Network
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by Fusarium solani CiteSeer Summary: Fusarium solani degraded methyl tert-butyl ether (MTBE) and other oxygenated compounds from gasoline including tert-butyl alcohol (TBA). The...
{gamma}-aminobutyric acid{sub A} (GABA{sub A}) receptor regulates ERK1/2 phosphorylation in rat hippocampus in high doses of Methyl Tert-Butyl Ether (MTBE)-induced impairment of spatial memory
Zheng Gang; Zhang Wenbin [Department of Occupational and Environmental Health, School of Public Health and Military Preventive Medicine, Fourth Military Medical University, Xi'an 710032 (China); Zhang Yun [465 Hospital, Jilin Medical College, Jilin 132001 (China); Chen Yaoming; Liu Mingchao; Yao Ting; Yang Yanxia; Zhao Fang [Department of Occupational and Environmental Health, School of Public Health and Military Preventive Medicine, Fourth Military Medical University, Xi'an 710032 (China); Li Jingxia; Huang Chuanshu [Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, New York 10987 (United States); Luo Wenjing [Department of Occupational and Environmental Health, School of Public Health and Military Preventive Medicine, Fourth Military Medical University, Xi'an 710032 (China)], E-mail: email@example.com; Chen Jingyuan [Department of Occupational and Environmental Health, School of Public Health and Military Preventive Medicine, Fourth Military Medical University, Xi'an 710032 (China)], E-mail: email@example.com
Experimental and occupational exposure to Methyl Tert-Butyl Ether (MTBE) has been reported to induce neurotoxicological and neurobehavioral effects, such as headache, nausea, dizziness, and disorientation, etc. However, the molecular mechanisms involved in MTBE-induced neurotoxicity are still not well understood. In the present study, we investigated the effects of MTBE on spatial memory and the expression and function of GABA{sub A} receptor in the hippocampus. Our results demonstrated that intraventricular injection of MTBE impaired the performance of the rats in a Morris water maze task, and significantly increased the expression of GABA{sub A} receptor {alpha}1 subunit in the hippocampus. The phosphorylation of ERK1/2 decreased after the MTBE injection. Furthermore, the decreased ability of learning and the reduction of phosphorylated ERK1/2 level of the MTBE-treated rats was partly reversed by bicuculline injected 30 min before the training. These results suggested that MTBE exposure could result in impaired spatial memory. GABA{sub A} receptor may play an important role in the MTBE-induced impairment of learning and memory by regulating the phosphorylation of ERK in the hippocampus.
Efficient Energy Usage in Butane Splitters
Barnwell, J.; Morris, C. P.
A World surplus of mixed butanes coupled with an increased need for gasoline extenders has raised the demand for isobutane. Isobutane is readily separated from an admixture with normal butane by conventional distillation techniques. However...
Mode of action of ethyl tertiary-butyl ether hepatotumorigenicity in the rat: Evidence for a role of oxidative stress via activation of CAR, PXR and PPAR signaling pathways
Kakehashi, Anna, E-mail: email@example.com [Department of Pathology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan); Hagiwara, Akihiro; Imai, Norio [DIMS Institute of Medical Science, Inc., 64 Goura, Nishiazai, Azai-cho, Ichinomiya, Aichi 491-0113 (Japan); Nagano, Kasuke [Nagano Toxicologic-Pathology Consulting, Ochiai, Hadano, Kanagawa 257-0025 (Japan); Nishimaki, Fukumi [Biofuel Assessment Group, New Fuels Dept., Japan Petroleum Energy Center (JPEC), 4-3-9 Toranomon, Minato-ku, Tokyo 105-0001 (Japan); Banton, Marcy [Toxicology and Risk Assessment, LyondellBasell Industries, LyondellBasell Corporate HSE/Product Safety, One Houston Center, Suite 700, 1221 McKinney Street, Houston, TX 770 10 (United States); Wei, Min [Department of Pathology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan); Fukushima, Shoji [Department of Pathology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan); Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445 Hirasawa, Hadano, Kanagawa 257-0011 (Japan); Wanibuchi, Hideki [Department of Pathology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan)
To elucidate possible mode of action (MOA) and human relevance of hepatotumorigenicity in rats for ethyl tertiary-butyl ether (ETBE), male F344 rats were administered ETBE at doses of 0, 150 and 1000 mg/kg body weight twice a day by gavage for 1 and 2 weeks. For comparison, non-genotoxic carcinogen phenobarbital (PB) was applied at a dose of 500 ppm in diet. Significant increase of P450 total content and hydroxyl radical levels by low, high doses of ETBE and PB treatments at weeks 1 and 2, and 8-OHdG formation at week 2, accompanied accumulation of CYP2B1/2B2, CYP3A1/3A2 and CYP2C6, and downregulation of DNA oxoguanine glycosylase 1, induction of apoptosis and cell cycle arrest in hepatocytes, respectively. Up-regulation of CYP2E1 and CYP1A1 at weeks 1 and 2, and peroxisome proliferation at week 2 were found in high dose ETBE group. Results of proteome analysis predicted activation of upstream regulators of gene expression altered by ETBE including constitutive androstane receptor (CAR), pregnane-X-receptor (PXR) and peroxisome proliferator-activated receptors (PPARs). These results indicate that the MOA of ETBE hepatotumorigenicity in rats may be related to induction of oxidative stress, 8-OHdG formation, subsequent cell cycle arrest, and apoptosis, suggesting regenerative cell proliferation after week 2, predominantly via activation of CAR and PXR nuclear receptors by a mechanism similar to that of PB, and differentially by activation of PPARs. The MOA for ETBE hepatotumorigenicity in rats is unlikely to be relevant to humans. - Highlights: • We focus on MOA and human relevance of hepatotumorigenicity in rats for ETBE. • ETBE was administered to F344 rats for 1 and 2 weeks. • Oxidative stress formation, proliferation and apoptosis in the liver are analyzed. • ETBE-induced changes of gene and protein expression in the liver are examined. • The effects are compared with those induced by non-genotoxic carcinogen PB.
Etherify field butanes: Part 2
Sarathy, P.R. (John Brown, Houston, TX (United States)); Suffridge, G.S. (John Brown, Tulsa, OK (United States))
Worldwide interest in technical details concerning major components of world-scale MTBE complexes continues. Part 1 reviewed alternate scenarios for MTBE production and basic technological considerations to assess component processes for producing MTBE. Commercial technologies and cost considerations for world-scale MTBE complexes call for a focus on butane isomerization, isobutane dehydrogenation and isobutylene etherification. The paper describes isomerization; four commercial processes for dehydrogenation (Oleflex, Catofin, STAR, and FBD-4 processes); three methods for etherification (fixed bed with recycle, fixed bed tubular reactor, and catalytic distillation); and capital and production costs for the MTBE complex.
Ignition properties of n-butane and iso-butane in a rapid compression machine
Gersen, S.; Darmeveil, J.H. [Gasunie Engineering and Technology, P.O. Box 19, 9700 MA Groningen (Netherlands); Mokhov, A.V. [Laboratory for Fuel and Combustion Science, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands); Levinsky, H.B. [Gasunie Engineering and Technology, P.O. Box 19, 9700 MA Groningen (Netherlands); Laboratory for Fuel and Combustion Science, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands)
Autoignition delay times of n-butane and iso-butane have been measured in a Rapid Compression Machine in the temperature range 660-1010 K, at pressures varying from 14 to 36 bar and at equivalence ratios {phi} = 1.0 and {phi} = 0.5. Both butane isomers exhibit a negative-temperature-coefficient (NTC) region and, at low temperatures, two-stage ignition. At temperatures below {proportional_to}900 K, the delay times for iso-butane are longer than those for the normal isomer, while above this temperature both butanes give essentially the same results. At temperatures above {proportional_to}720 K the delay times of the lean mixtures are twice those for stoichiometric compositions; at T < 720 K, the equivalence ratio is seen to have little influence on the ignition behavior. Increasing the pressure from 15 bar to 30 bar decreases the amplitude of the NTC region, and reduces the ignition delay time for both isomers by roughly a factor of 3. In the region in which two-stage ignition is observed, 680-825 K, the duration of the first ignition stage decreases sharply in the range 680-770 K, but is essentially flat above 770 K. Good quantitative agreement is found between the measurements and calculations for n-butane using a comprehensive model for butane ignition, including both delay times in the two-stage region, with substantial differences being observed for iso-butane, particularly in the NTC region. (author)
Firing Excess Refinery Butane in Peaking Gas Turbines
Pavone, A.; Schreiber, H.; Zwillenberg, M.
normal butane production, which will reduce refinery normal butane value and price. Explored is an opportunity for a new use for excess refinery normal butane- as a fuel for utility peaking gas turbines which currently fire kerosene and #2 oil. Our paper...
Firing Excess Refinery Butane in Peaking Gas Turbines
Pavone, A.; Schreiber, H.; Zwillenberg, M.
normal butane production, which will reduce refinery normal butane value and price. Explored is an opportunity for a new use for excess refinery normal butane- as a fuel for utility peaking gas turbines which currently fire kerosene and #2 oil. Our paper...
Production of methyl tert-alkyl ethers
Trofimov, V.A.
The transition to the use of unleaded gasolines has required the replacement of tetraethyl lead by oxygen-containing compounds such as methanol, ethanol, and ethers, which are termed {open_quotes}oxygenates{close_quotes} in the technical literature. These may be used in commercial gasolines in amounts of 10-15% by volume, equivalent to 2% oxygen by weight. When methyl tert-butyl ether (MTBE) is used, the oxygen content may amount to 2.7% by weight. This oxygenate gives a significant improvement of knock resistance of naphtha fractions, the greatest effects being observed for straight-run naphthas and reformer naphthas produced under normal conditions; the MTBE also improves the engine power and economy characteristics and lowers the carbon monoxide content in the exhaust by 15-30% and the hydrocarbon content by 7-8%. This paper describes methods for the production of MTBE and also methyl tert-alkyl ethers.
Radiation chemistry of alternative fuel oxygenates -- Substituted ethers
Mezyk, S. P.; Cooper, W. J.; Bartels, D. M.; Tobien, T.; O'Shea, K. E.
The electron beam process, an advanced oxidation and reduction technology, is based in the field of radiation chemistry. Fundamental to the development of treatment processes is an understanding of the underlying chemistry. The authors have previously evaluated the bimolecular rate constants for the reactions of methyl tert-butyl ether (MTBE) and with this study have extended their studies to include ethyl tert-butyl ether (ETBE), di-isopropyl ether (DIPE) and tert-amyl methyl ether (TAME) with the hydroxyl radical, hydrogen atom and solvated electron using pulse radiolysis. For all of the oxygenates the reaction with the hydroxyl radical appears to be of primary interest in the destruction of the compounds in water. The rates with the solvated electron are limiting values as the rates appear to be relatively low. The hydrogen atom rate constants are relatively low, coupled with the low yield in radiolysis, they concluded that these are of little significance in the destruction of the alternative fuel oxygenates (and MTBE).
Adsorption of iso-/n-butane on an Anatase Thin Film: A Molecular...
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iso-n-butane on an Anatase Thin Film: A Molecular Beam Scattering and TDS Study. Adsorption of iso-n-butane on an Anatase Thin Film: A Molecular Beam Scattering and TDS Study....
Butane segregated by fluorides, olefins content at Texas terminals
Not Available
Texas Eastern Products Pipeline Co., Houston (Teppco), this month has begun segregating butane streams at the company's Mont Belvieu and Baytown, Texas terminals according to fluoride and olefin contents. Streams containing fluoride or an olefin content greater than 1 ppm (or both) currently flow into Teppco's south Mont Belvieu terminal. Those fluoride-free streams with less than 1 ppm of olefins flow to its north Mont Belvieu terminal. Butane processed through an isomerization unit yields isobutane, a key component in MTBE. But high-fluoride butane from crude-oil refineries using hydrofluoric (HF) acid alkylation units cannot be used to produce MTBE because fluoride will damage isomerization units' process catalysts. Olefins also affect the efficiency of isomerization units, but less critically than fluorides. Their presence is higher in refinery product than in fractionated NGL. To extend the life of their process catalysts and to maximize yields, producers (including MTBE and isomerization unit operators) are specifying low-fluoride butanes developed from natural-gas fractionators or from refineries that do not use an HF process.
High octane ethers from synthesis gas-derived alcohols
Klier, K.; Herman, R.G.; Feeley, O.C.; Johansson, M.A.
The objective of the proposed research is to synthesize high octane ethers, primarily methyl isobutyl ether (MIBE) and methyl tertiary butyl ether (MTBE), directly from H[sub 2]/CO/CO[sub 2] coal-derived synthesis gas via alcohol mixtures that are rich in methanol and 2-methyl-l-propanol (isobutanol). The overall scheme involves gasification of coal, purification and shifting of the synthesis gas, higher alcohol synthesis, and direct synthesis of ethers. The last stage of the synthesis involves direct coupling of synthesis gas-derived methanol and isobutanol that has been demonstrated by us to occur over superacid catalysts to yield methyl isobutyl ether (MIBE) at moderate pressures and a mixture of methanol and isobutene at low pressures. MIBE is an isomer of MTBE and a process is proposed whereby MTBE from the two alcohols is maximized and MIBE is minimized. This will be achieved by the proper choice of reaction conditions, i.e. intermediate pressures, and of inorganic acid catalysts that are stable at temperatures higher than 200[degree]C, at which the carbonium ion reaction coupling of the two alcohols to MTBE is more effective than the oxonium ion or ester reaction coupling to MIBE. Both organic and inorganic catalysts will be investigated, and the better catalysts of these classes will be subjected to long term performance studies. The long term performance studies of the combined process will extend to 1000 hr and detailed analytical data for all products will be provided.
Aerobic mineralization of MTBE and tert-butyl alcohol by stream-bed sediment microorganisms
Bradley, P.M.; Landmeyer, J.E.; Chapelle, F.H. [Geological Survey, Columbia, SC (United States)] [Geological Survey, Columbia, SC (United States)
Microorganisms indigenous to the stream-bed sediments at two gasoline-contaminated groundwater sites demonstrated significant mineralization of the fuel oxygenates, methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA). Up to 73% of [U-{sup 14}C]-MTBE and 84% of [U-{sup 14}C]-TBA were degraded to {sup 14}CO{sub 2} under mixed aerobic/anaerobic conditions. No significant mineralization was observed under strictly anaerobic conditions. The results indicate that, under the mixed aerobic/anaerobic conditions characteristic of stream-bed sediments, microbial processes may provide a significant environmental sink for MTBE and TBA delivered to surface water bodies by contaminated groundwater or by other sources.
ADSORPTION AND BONDING OF BUTANE AND PENTANE ON THE Pt(111) CRYSTAL SURFACES. EFFECTS OF OXYGEN TREATMENTS AND DEUTERIUM PREADSORPTION
Salmeron, M.
which may be due to its adsorption on D-covered regions.of Physical Chemistry ADSORPTION AND BONDING OF BUTANE ANDof California. LBL 12617 ADSORPTION AND BONDING OF BUTANE
Improving fractionation lowers butane sulfur level at Saudi gas plant
Harruff, L.G.; Martinie, G.D.; Rahman, A. [Saudi Arabian Oil Co., Dhahran (Saudi Arabia)
Increasing the debutanizer reflux/feed ratio to improve fractionation at an eastern Saudi Arabian NGL plant reduced high sulfur in the butane product. The sulfur resulted from dimethyl sulfide (DMS) contamination in the feed stream from an offshore crude-oil reservoir in the northern Arabian Gulf. The contamination is limited to two northeastern offshore gas-oil separation plants operated by Saudi Arabian Oil Co. (Saudi Aramco) and, therefore, cannot be transported to facilities outside the Eastern Province. Two technically acceptable solutions for removing this contaminant were investigated: 13X molecular-sieve adsorption of the DMS and increased fractionation efficiency. The latter would force DMS into the debutanizer bottoms.
Process for producing high purity isoolefins and dimers thereof by dissociation of ethers
Smith, L.A. Jr.; Jones, E.M. Jr.; Hearn, D.
Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150 to 250 F at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C[sub 3] to C[sub 6] and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom. 2 figs.
Process for producing high purity isoolefins and dimers thereof by dissociation of ethers
Smith, Jr., Lawrence A. (Bellaire, TX); Jones, Jr., Edward M. (Friendswood, TX); Hearn, Dennis (Houston, TX)
Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150.degree. to 250.degree. F. at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C.sub.3 to C.sub.6 and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom.
amine methanol, ether . Amine amine CO2
Hong, Deog Ki
IP [2012] 7 C O 2 (CO2) . CO2 amine methanol, ether . Amine amine CO2 CO2 .Amine CO2 (functional group) amine amine+ +promoter .Amine CO2 CO2 . . , methanol ether methanol, ether promoter CO2 CO2 H2S, COS CO2 . Methanol rectisol process, di-methylene ether polypropylene glycol selexol (-30oC) . CO2
Biodegradation of methyl tertiary butyl ether (MTBE) using a granular activated carbon trickling filter
Converse, B.M.; Schroeder, E.D.; Chang, D.P.Y.
A pilot scale trickling filter was constructed using granular activated carbon (GAC) as the packing medium and inoculated with a microbial culture known to degrade MTBE. The packing dimensions were 0.076 m in diameter and 0.22 m deep. The unit operated with recycling flow for two months before a biofilm was observed on the GAC. After two additional months the biofilm had visibly spread throughout the packing. A few pieces of GAC were placed in a sealed bottle with MTBE-contaminated water and nutrients. Headspace analysis performed over 14 days confirmed that MTBE degradation was occurring. The trickling filter was converted to continuous flow and operated for one month at a nominal flow rate of 0.1 L/min and a hydraulic loading rate of 32 m{sup 3}/m{sup 2}-d. Samples were collected for analysis at the spray nozzle and at the bottom of the trickling filter. Fractional removal varied with influent MTBE concentration, temperature and liquid flow rate. Percent MTBE removal was as high as 85%. A mechanical failure resulted in the trickling filter bed drying and percent removal dropping to less than 1 percent. However, the system recovered within five days.
Surface Adsorption Isotherms and Surface Excess Densities of n-Butane in Silicalite-1
Kjelstrup, Signe
Surface Adsorption Isotherms and Surface Excess Densities of n-Butane in Silicalite-1 Isabella 27, 2008. ReVised Manuscript ReceiVed NoVember 13, 2008 We present isotherms for the adsorption of n were considered: a flat surface having only one adsorption site and a surface with a zigzag texture
METHANE AND n-BUTANE OXIDATION WITH CO2 UNDER RADIOFREQUENCY PLASMAS OF MODERATE PRESSURES (*)
Boyer, Edmond
the gas to the reactor walls. It is capacitively coupled to the radiofrequency generator (35 MHz, 10 k ) and constant pressure of 20 torr. Experimental details on discharges parameters, sampling procedure, gas analy1205 METHANE AND n-BUTANE OXIDATION WITH CO2 UNDER RADIOFREQUENCY PLASMAS OF MODERATE PRESSURES
High octane ethers from synthesis gas-derived alcohols. Quarterly technical progress report, April--June 1992
Klier, K.; Herman, R.G.; Feeley, O.C.; Johansson, M.A.
The objective of the proposed research is to synthesize high octane ethers, primarily methyl isobutyl ether (MIBE) and methyl tertiary butyl ether (MTBE), directly from H{sub 2}/CO/CO{sub 2} coal-derived synthesis gas via alcohol mixtures that are rich in methanol and 2-methyl-l-propanol (isobutanol). The overall scheme involves gasification of coal, purification and shifting of the synthesis gas, higher alcohol synthesis, and direct synthesis of ethers. The last stage of the synthesis involves direct coupling of synthesis gas-derived methanol and isobutanol that has been demonstrated by us to occur over superacid catalysts to yield methyl isobutyl ether (MIBE) at moderate pressures and a mixture of methanol and isobutene at low pressures. MIBE is an isomer of MTBE and a process is proposed whereby MTBE from the two alcohols is maximized and MIBE is minimized. This will be achieved by the proper choice of reaction conditions, i.e. intermediate pressures, and of inorganic acid catalysts that are stable at temperatures higher than 200{degree}C, at which the carbonium ion reaction coupling of the two alcohols to MTBE is more effective than the oxonium ion or ester reaction coupling to MIBE. Both organic and inorganic catalysts will be investigated, and the better catalysts of these classes will be subjected to long term performance studies. The long term performance studies of the combined process will extend to 1000 hr and detailed analytical data for all products will be provided.
Kinetics and mechanism of the thermal dissociation of O,O'-bis(1,3,5-TRI-tert-butyl-4-oxo-2,5-cyclo-hexadienyl)-p-benzoquinone dioxime in solution
Khizhnyi, V.A.; Danilova, T.A.; Goloverda, G.Z.; Dobronravova, Z.A.
The kinetics and mechanism of the thermal dissociation of O,O'-bis(1,3,5-tri-tert-butyl-4-oxo-2,5-cyclohexadienyl)-p-benzoquinone dioxime (quinol ether) in solutions in nonpolar solvents were investigated. The dissociation of the quinol ether is reversible two-stage process and involves the formation of an intermediate radical. In relation to the reaction conditions (initial concentration, temperature) the dissociation rate of the quinol ether obeys the kinetic equations omega = k/sub eff/ x c/sup 1/2/ or omega = k/sub 1/c. The change in the reaction order is due to the ratio of the rates of dissociation of the intermediate radical and of its reaction with the phenoxyl radical. The ESR spectra were recorded on a Varian E-9 radiospectrometer with high-frequency modulation of 100 kHz.
Aza crown ether compounds as anion receptors
Lee, H.S.; Yang, X.O.; McBreen, J.
A family of aza-ether based compounds including linear, multi-branched and aza-crown ethers is provided. When added to non-aqueous battery electrolytes, the new family of aza-ether based compounds acts as neutral receptors to complex the anion moiety of the electrolyte salt thereby increasing the conductivity and the transference number of LI{sup +} ion in alkali metal batteries. 3 figs.
Near-Infrared Electrochromism in Electroactive Pentacenediquinone-Containing Poly(aryl ether)s
Wan, Xin-hua
Near-Infrared Electrochromism in Electroactive Pentacenediquinone-Containing Poly(aryl etherVed October 21, 2005 The synthesis and near-infrared electrochromic properties of pentacenediquinone-infrared electrochromic properties of pentacenediquinone-containing poly(aryl ether)s were studied
Crown Ethers in Graphene Bring Strong, Selective Binding | ornl...
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Materials Characterization Crown Ethers in Graphene Bring Strong, Selective Binding November 14, 2014 Schematic showing a graphene sheet containing an array of ideal crown ethers....
Purification of aqueous cellulose ethers
Bartscherer, K.A.; de Pablo, J.J.; Bonnin, M.C.; Prausnitz, J.M.
Manufacture of cellulose ethers usually involves high amounts of salt by-products. For application of the product, salt must be removed. In this work, we have studied the injection of high-pressure CO{sub 2} into an aqueous polymer-salt solution; we find that upon addition of isopropanol in addition to CO{sub 2}, the solution separates into two phases. One phase is rich in polymer and water, and the other phase contains mostly isopropanol, water and CO{sub 2}. The salt distributes between the two phases, thereby offering interesting possibilities for development of a new purification process for water-soluble polymers. This work presents experimental phase-equilibrium data for hydroxyethyl cellulose and sodium carboxymethyl cellulose with sodium acetate and potassium sulfate, respectively, in the region 40{degree}C and 30 to 80 bar. Based on these data, we suggest a process for the manufacture and purification of water-soluble cellulose ethers. 15 refs., 14 figs., 9 tabs.
Impacts of Ethanol on Anaerobic Production of Tert-Butyl Alcohol (TBA) from Methyl Tert-Butyl Ether (MTBE) in Groundwater
Scow, K M; MacKay, Douglas
Project title: Impacts of Ethanol on Anaerobic Production oftert-butanol (TBA). As ethanol is being promoted as ainvestigate the effect of ethanol release on existing MTBE
Impacts of Ethanol on Anaerobic Production of Tert-Butyl Alcohol (TBA) from Methyl Tert-Butyl Ether (MTBE) in Groundwater
Scow, K M; MacKay, Douglas
field site is located at the Vandenberg Air Force Base at a site where a leaking underground storage
Production of olefins by oxidative dehydrogenation of propane and butane over monoliths at short contact times
Huff, M.; Schmidt, L.D. [Univ. of Minnesota, Minneapolis, MN (United States)] [Univ. of Minnesota, Minneapolis, MN (United States)
The autothermal production of olefins from propane or n-butane by oxidative dehydrogenation and cracking in air or oxygen at atmospheric pressure over noble metal coated ceramic foam monoliths at contact times of {approximately}5 milliseconds has been studied. On Pt, synthesis gas (CO and H{sub 2}) dominates near its stoichiometry, while olefin production dominates at higher fuel-to-oxygen ratios. No carbon buildup is observed, and catalysts exhibit no deactivation over at least several days. On Rh, primarily synthesis gas is produced under these conditions, while on Pd, carbon deposition rapidly deactivates the catalyst. The authors observed up to 65% selectivity to olefins at nearly 100% conversion of propane or n-butane with a catalyst contact time of 5 ms. Ethylene selectivity is maximized by increasing the reaction temperature, either by preheating the reactants or by using oxygen enriched air. Propylene selectivity is maximized by lower temperature and shorter catalyst contact time. Very small amounts alkanes and higher molecular weight species are obtained, suggesting that a homogeneous pyrolysis mechanism is not occurring. A very simple reaction mechanism appears to explain the observed product distribution. Reactions are initiated by oxidative dehydrogenation of the alkane by adsorbed oxygen to form a surface alkyl. On Pt, {beta}-hydrogen and {beta}-alkyl elimination reactions of adsorbed alkyl dominate which lead to olefin production rather than cracking to C{sub s} and H{sub s}. 24 refs., 14 figs., 4 tabs.
Support shape effect in metal oxide catalysis: ceria nanoshapes supported vanadia catalysts for oxidative dehydrogenation of iso-butane
Wu, Zili [ORNL; Schwartz, Viviane [ORNL; Li, Meijun [ORNL; Rondinone, Adam Justin [ORNL; Overbury, Steven {Steve} H [ORNL
The activation energy of VOx/CeO2 catalysts in oxidative dehydrogenation of iso-butane was found dependent on the shape of ceria support: rods < octahedra, closely related to the surface oxygen vacancy formation energy and defects amount of the two ceria supports with different crystallographic surface planes.
Methyl tertiary butyl ether (MtBE) contamination of the City of Santa Monica drinking water supply
Brown, A.; Farrow, J.R.C. [Komex H2O Science, Huntington Beach, CA (United States); Rodriguez, R.A. [City of Santa Monica, CA (United States)] [and others
In the summer of 1996, the City of Santa Monica ceased pumping groundwater from two Well Fields (Charnock and Arcadia) used for public drinking water supply due to persistent and increasing concentrations of MtBE in all seven municipal water supply wells. This lost production accounted for 50% of the City`s total drinking water supply. In late 1996, the City, in cooperation with State and Federal agencies, initiated an investigation of MtBE contamination at the two well fields. The objectives of the investigation were as follows: (1) Review available data on the production, use, chemical characteristics, fate and transport, toxicology, and remediation of MtBE; (2) Identify locations of potential sources of MtBE groundwater contamination at the well fields; (3) Develop an understanding of the hydrologic pathways from the potential sources to the drinking water wells; and (4) Evaluate alternative treatment technologies for the removal of MtBE from drinking water. In addition to a review of available information about MtBE, the investigation included an extensive review of literature and available data relevant to the well fields, including well field production histories, site and regional hydrogeology, all well logs and production in the groundwater basins, general groundwater quality, and the record of MtBE detection. Based upon the review of background information, conceptual hydrogeologic models were developed. A detailed review of agency files for over 45 potential source sites was conducted. The information from this review was summarized, and source site screening and ranking criteria were developed. A field program was conducted at the major well field (Charnock), including soil gas surveys, CPTs, soil borings and well installations, geophysics, and aquifer testing. The field program provided site data which allowed the conceptual hydrogeologic model to be refitted to actual site conditions.
Whole-Genome Analysis of Methyl tert-Butyl Ether-Degrading Beta-Proteobacterium Methylibium petroleiphilum PM1
D. J. Slomczynski. 2003. BTEX/MTBE bioremediation: BionetsScow, and L. Alvarez-Cohen. MTBE and benzene biodegradationinteractions in BTEX and MTBE mixtures by an MTBE-degrading
Review of potential technologies for the treatment of Methyl tertiary butyl Ether (MtBE) in drinking water
Brown, A.; Browne, T.E. [Komex H2O Science, Huntington Beach, CA (United States); Devinny, J.S. [Univ. of Southern California, Los Angeles, CA (United States)] [and others
At present, the state of knowledge on effective treatment technologies for MtBE in drinking water, and groundwater in general, is limited. Research by others is focusing on the remediation of MtBE close to the point of release. The City of Santa Monica, MWD, Komex and USC are currently conducting research into different technologies that could be used to remove MtBE from drinking water supplies. The objectives of the research are to evaluate different treatment technologies to identify cost-effective and technically feasible alternatives for the removal of MtBE from drinking water. The evaluation is considering moderate to high water flow rates (100 to 2,000+ gpm) and low to moderate MtBE concentrations (<2,000 {mu}g/l). The research program includes four phases: (1) Literature Review; (2) Bench Scale Study; (3) Field Scale Pre-pilot Study; and (4) Summary Evaluation. This paper presents some preliminary information and findings from the first phase of this research - the literature review. The review discusses the chemical properties of MtBE and how they affect remediation and thus, an evaluation of alternative treatment technologies. The review of available literature, and the applicability and limitations of the following technologies are presented in detail.
Whole-Genome Analysis of Methyl tert-Butyl Ether-Degrading Beta-Proteobacterium Methylibium petroleiphilum PM1
2003. BTEX/MTBE bioremediation: Bionets containing Isolite,In Situ and On-site Bioremediation Symposium. Battellebacteria for use in bioremediation. FEMS Lett. 22. Dennis,
Comparative Environmental Performance of Two-Diesel-Fuel Oxygenates: Dibutyl Maleate (DBM) and Triproplyene Glycol Monomethyl Ether (TGME)
Layton, D.W.; Marchetti, A.A.
Many studies have shown that the addition of oxygen bearing compounds to diesel fuel can significantly reduce particulate emissions. To assist in the evaluation of the environmental performance of diesel-fuel oxygenates, we have implemented a suite of diagnostic models for simulating the transport of compounds released to air, water, and soils/groundwater as well as regional landscapes. As a means of studying the comparative performance of DBM and TGME, we conducted a series of simulations for selected environmental media. Benzene and methyl tertiary butyl ether (MTBE) were also addressed because they represent benchmark fuel-related compounds that have been the subject of extensive environmental measurements and modeling. The simulations showed that DBM and TGME are less mobile in soil because of reduced vapor-phase transport and increased retention on soil particles. The key distinction between these two oxygenates is that DBM is predicted to have a greater potential than TGME for aerobic biodegradation, based on chemical structure.
MTBE will be a boon to U. S. gas processors
Otto, K.W. (Purvin and Gertz, Inc. Dallas, TX (United States))
This paper reports that the advent of methyl tertiary butyl ether (MTBE) as the primary oxygenate blending component for oxygenated and reformulated motor fuels promises significant benefits for the U.S. gas-processing industry. Increased demand for isobutane as MTBE-plant feedstock will buoy both normal butane and isobutane pricing in U.S. gulf Coast during the 1990s. Elimination of the need to crack normal butane in U.S. olefin plants will also strengthen competitive feedstocks somewhat, including ethane and propane. And increased use of normal butane as isomerization feedstock will result in wider recognition of the premium quality of gas plant normal butane production compared to most refinery C[sub 4] production.
Vacuum structure and ether-drift experiments
M. Consoli; L. Pappalardo
In the data of the ether-drift experiments there might be sizable fluctuations superposed on the smooth sinusoidal modulations due to the Earth's rotation and orbital revolution. These fluctuations might reflect the stochastic nature of the underlying "quantum ether" and produce vanishing averages for all vectorial quantities extracted from a naive Fourier analysis of the data. By comparing the typical stability limits of the individual optical resonators with the amplitude of their relative frequency shift, the presently observed signal, rather than being spurious experimental noise, might also express fundamental properties of a physical vacuum similar to a superfluid in a turbulent state of motion. In this sense, the situation might be similar to the discovery of the CMBR that was first interpreted as mere instrumental noise.
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Crown Ethers Flatten in Graphene for Strong, Specific Binding...
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SHARE Crown Ethers Flatten in Graphene for Strong, Specific Binding ORNL discovery holds potential for separations, sensors, batteries, biotech and more This sheet of graphene...
Alternative Fuels lDimethyl Ether Rheology and Materials Studies...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
& Publications Research on Fuels & Lubricants Development of a Dimethyl Ether (DME)-Fueled Shuttle Bus Ionic Liquids as Multifunctional Ashless Additives for Engine Lubrication...
Divinyl ether synthase gene, and protein and uses thereof
Howe, Gregg A.; Itoh, Aya
The present invention relates to divinyl ether synthase genes, proteins, and methods of their use. The present invention encompasses both native and recombinant wild-type forms of the synthase, as well as mutants and variant forms, some of which possess altered characteristics relative to the wild-type synthase. The present invention also relates to methods of using divinyl ether synthase genes and proteins, including in their expression in transgenic organisms and in the production of divinyl ether fatty acids, and to methods of suing divinyl ether fatty acids, including in the protection of plants from pathogens.
Divinyl ether synthase gene and protein, and uses thereof
Howe, Gregg A. (East Lansing, MI); Itoh, Aya (Tsuruoka, JP)
The present invention relates to divinyl ether synthase genes, proteins, and methods of their use. The present invention encompasses both native and recombinant wild-type forms of the synthase, as well as mutants and variant forms, some of which possess altered characteristics relative to the wild-type synthase. The present invention also relates to methods of using divinyl ether synthase genes and proteins, including in their expression in transgenic organisms and in the production of divinyl ether fatty acids, and to methods of suing divinyl ether fatty acids, including in the protection of plants from pathogens.
Kinetic and inhibition studies for the aerobic cometabolism of 1,1,1-trichloroethane, 1,1-dichloroethylene, and 1,1-dichloroethane by a butane-grown mixed culture
Semprini, Lewis
was indicated from direct linear plots, and the CAHs also competitively inhibited butane utilization. 1,1-DCE indicator of competitive inhibition observed. Butane was a strong inhibitor of CAH transformation, having different inhibition types were observed among the compounds. Competitive inhibition among CAHs
Process for producing dimethyl ether from synthesis gas
Pierantozzi, R.
This invention pertains to a Fischer Tropsch process for converting synthesis gas to an oxygenated hydrocarbon with particular emphasis on dimethyl ether. Synthesis gas comprising carbon monoxide and hydrogen are converted to dimethyl ether by carrying out the reaction in the presence of an alkali metal-manganese-iron carbonyl cluster incorporated onto a zirconia-alumina support.
Process for producing dimethyl ether form synthesis gas
Pierantozzi, Ronald (Macungie, PA)
This invention pertains to a Fischer Tropsch process for converting synthesis gas to an oxygenated hydrocarbon with particular emphasis on dimethyl ether. Synthesis gas comprising carbon monoxide and hydrogen are converted to dimethyl ether by carrying out the reaction in the presence of an alkali metal-manganese-iron carbonyl cluster incorporated onto a zirconia-alumina support.
Synthesis of Methanol and Dimethyl Ether from Syngas over Pd...
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Methanol and Dimethyl Ether from Syngas over PdZnOAl2O3 Catalysts. Synthesis of Methanol and Dimethyl Ether from Syngas over PdZnOAl2O3 Catalysts. Abstract: A PdZnOAl2O3...
Statistical thermodynamics of 1-butanol, 2-methyl-1-propanol, and butanal Prasenjit Seal, Ewa Papajak, Tao Yu, and Donald G. Truhlar
Truhlar, Donald G
-body decomposition of ethanedial, propanal, propenal, n-butane, 1-butene, and 1,3-butadiene J. Chem. Phys. 136 investigation is to calculate partition functions and thermodynamic quan- tities, viz., entropy, enthalpy, heat- tant roles in alternative-fuel combustion.1Â5 Therefore, accu- rate estimation of the thermodynamic
Origin of mechanical modifications in poly (ether ether ketone)/carbon nanotube composite
Pavlenko, Ekaterina; Puech, Pascal; Bacsa, Wolfgang, E-mail: firstname.lastname@example.com [CEMES-CNRS and University of Toulouse, 29 Jeanne Marvig, 31055 Toulouse (France); Boyer, François; Olivier, Philippe [Université de Toulouse, Institut Clément Ader, I.U.T. Université Paul Sabatier - 133C Avenue de Rangueil - B.P. 67701, 31077 Toulouse CEDEX 4 (France); Sapelkin, Andrei [School of Physics and Astronomy, Queen Mary, University of London, Mile End Road, E1 4NS London (United Kingdom); King, Stephen; Heenan, Richard [ISIS Facility, Rutherford Appleton Laboratory, Chilton, OX11 0QX Didcot (United Kingdom); Pons, François; Gauthier, Bénédicte; Cadaux, Pierre-Henri [AIRBUS FRANCE (B.E. M and P Toulouse), 316 Route de Bayonne, 31060 Toulouse (France)
Variations in the hardness of a poly (ether ether ketone) beam electrically modified with multi-walled carbon nanotubes (MWCNT, 0.5%-3%) are investigated. It is shown that both rupture and hardness variations correlate with the changes in carbon nanotube concentration when using micro indentation and extended Raman imaging. Statistical analysis of the relative spectral intensities in the Raman image is used to estimate local tube concentration and polymer crystallinity. We show that the histogram of the Raman D band across the image provides information about the amount of MWCNTs and the dispersion of MWCNTs in the composite. We speculate that we have observed a local modification of the ordering between pure and modified polymer. This is partially supported by small angle neutron scattering measurements, which indicate that the agglomeration state of the MWCNTs is the same at the concentrations studied.
Molecular Mechanism of Polybrominated Diphenyl Ether Disposition in the Liver
Pacyniak, Erik Kristofer
Polybrominated diphenyl ethers (PBDEs) were introduced in the late 1970's as additive flame retardants incorporated into textiles, electronics, plastics and furniture. Although 2,2',3,3',4,4',5,5',6,6'-decabromodiphenyl ...
Effects of simulant mixed waste on EPDM and butyl rubber
Nigrey, P.J.; Dickens, T.G.
The authors have developed a Chemical Compatibility Testing Program for the evaluation of plastic packaging components which may be used in transporting mixed waste forms. In this program, they have screened 10 plastic materials in four liquid mixed waste simulants. These plastics were butadiene-acrylonitrile copolymer (Nitrile) rubber, cross-linked polyethylene, epichlorohydrin rubber, ethylene-propylene (EPDM) rubber, fluorocarbons (Viton and Kel-F{trademark}), polytetrafluoro-ethylene (Teflon), high-density polyethylene, isobutylene-isoprene copolymer (Butyl) rubber, polypropylene, and styrene-butadiene (SBR) rubber. The selected simulant mixed wastes were (1) an aqueous alkaline mixture of sodium nitrate and sodium nitrite; (2) a chlorinated hydrocarbon mixture; (3) a simulant liquid scintillation fluid; and (4) a mixture of ketones. The screening testing protocol involved exposing the respective materials to approximately 3 kGy of gamma radiation followed by 14-day exposures to the waste simulants at 60 C. The rubber materials or elastomers were tested using Vapor Transport Rate measurements while the liner materials were tested using specific gravity as a metric. The authors have developed a chemical compatibility program for the evaluation of plastic packaging components which may be incorporated in packaging for transporting mixed waste forms. From the data analyses performed to date, they have identified the thermoplastic, polychlorotrifluoroethylene, as having the greatest chemical compatibility after having been exposed to gamma radiation followed by exposure to the Hanford Tank simulant mixed waste. The most striking observation from this study was the poor performance of polytetrafluoroethylene under these conditions. In the evaluation of the two elastomeric materials they have concluded that while both materials exhibit remarkable resistance to these environmental conditions, EPDM has a greater resistance to this corrosive simulant mixed waste.
Process Design, Simulation and Integration of Dimethyl Ether (DME) Production from Shale Gas by Direct and Indirect Methods
Karagoz, Secgin
may be obtained from shale gas is dimethyl ether (DME). Dimethyl ether can be used in many areas such as power generation, transportation fuel, and domestic heating and cooking. Dimethyl ether is currently produced from natural gas, coal and biomass...
Paris-Sud XI, Université de
;NOMENCLATURE CV: closed vessel DIPE: di-isopropyl-ether ETBE: ethyl-tert-butyl-ether FR: flow reactor HCCI
Analysis of dissolved benzene plumes and methyl tertiary butyl ether (MTBE) plumes in ground water at leaking underground fuel tank (LUFT) sites
Happel, A.M.; Rice, D. [Lawrence Livermore National Lab., CA (United States); Beckenbach, E. [California Univ., Berkeley, CA (United States); Savalin, L.; Temko, H.; Rempel, R. [California State Water Resources Control Board, Sacramento, CA (United States); Dooher, B. [California Univ., Los Angeles, CA (United States)
The 1990 Clean Air Act Amendments mandate the addition of oxygenates to gasoline products to abate air pollution. Currently, many areas of the country utilize oxygenated or reformulated fuel containing 15- percent and I I-percent MTBE by volume, respectively. This increased use of MTBE in gasoline products has resulted in accidental point source releases of MTBE containing gasoline products to ground water. Recent studies have shown MTBE to be frequently detected in samples of shallow ground water from urban areas throughout the United States (Squillace et al., 1995). Knowledge of the subsurface fate and transport of MTBE in ground water at leaking underground fuel tank (LUFT) sites and the spatial extent of MTBE plumes is needed to address these releases. The goal of this research is to utilize data from a large number of LUFT sites to gain insights into the fate, transport, and spatial extent of MTBE plumes. Specific goals include defining the spatial configuration of dissolved MTBE plumes, evaluating plume stability or degradation over time, evaluating the impact of point source releases of MTBE to ground water, and attempting to identify the controlling factors influencing the magnitude and extent of the MTBE plumes. We are examining the relationships between dissolved TPH, BTEX, and MTBE plumes at LUFT sites using parallel approaches of best professional judgment and a computer-aided plume model fitting procedure to determine plume parameters. Here we present our initial results comparing dissolved benzene and MTBE plumes lengths, the statistical significance of these results, and configuration of benzene and MTBE plumes at individual LUFT sites.
The Effect of the Di-Tertiary Butyl Peroxide (DTBP) additive on HCCI Combustion of Fuel Blends of Ethanol and Diethyl Ether
Mack, John Hunter; Buchholz, Bruce A; Flowers, Daniel L; Dibble, Robert W
Charge Compression Ignition (HCCI) Engines: Key Research andJ. Girard, and R. Dibble, "HCCI in a CFR Engine: ExperimentsRyan III, and J.S. Souder, "HCCI Operation of a Dual-Fuel
The Ether Extract and the Chloroform Extract of Soils.
Fraps, G. S.; Rather, J. B.
I39-3I3-5m TEXAS AGRICULTURAL EXPERIMENT STATIONS BULLETIN NO. 155 JANUARY, 1913 DIVISION OF CHEMISTRY TECHNICAL BULLETIN THE ETHER EXTRACT AND THE CHLORO? FORM EXTRACT OF SOILS BY G. S. FRAPS and J. B. RATHER POSTOFFICE COLLEGE STATION... postal card will bring these publications. THE ETHER EXTRACT AND THE CHLOROFORM EXTRACT OF SOILS. (t. S. FliAPS , Chemist. ?J. B. o Y . C U G O Assistant Chemist. The soil may coDtarn any of the Substances which are found in plants or animals...
Kamil Klier; Richard G. Herman; James G.C. Shen; Qisheng Ma
A novel 1,2-ethanediol, bis(hydrogen sulfate), disodium salt precursor-based solid acid catalyst with a zirconia substrate was synthesized and demonstrated to have significantly enhanced activity and high selectivity in producing methyl isobutyl ether (MIBE) or isobutene from methanol-isobutanol mixtures. The precursor salt was synthesized and provided by Dr. T. H. Kalantar of the M.E. Pruitt Research Center, Dow Chemical Co., Midland, MI 48674. Molecular modeling of the catalyst synthesis steps and of the alcohol coupling reaction is being carried out. A representation of the methyl transfer from the surface activated methanol molecule (left) to the activated oxygen of the isobutanol molecule (right) to form an ether linkage to yield MIBE is shown.
Extraction of Plutonium into 30 Percent Tri-Butyl Phosphate from Nitric Acid Solution Containing Fluoride, Aluminum, and Boron
Kyser, E.A.
This work consists of experimental batch extraction data for plutonium into 30 volume-percent tri-butyl phosphate at ambient temperature from such a solution matrix and a model of this data using complexation constants from the literature.
Recanalization of Splenic Artery Aneurysm After Transcatheter Arterial Embolization Using N-Butyl Cyanoacrylate
Matsumoto, Keiji; Ushijima, Yasuhiro, E-mail: firstname.lastname@example.com; Tajima, Tsuyoshi; Nishie, Akihiro; Hirakawa, Masakazu; Ishigami, Kousei [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences (Japan); Yamaji, Yukiko [Kyushu University, Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences (Japan); Honda, Hiroshi [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences (Japan)
A 65-year-old woman who had been diagnosed as having microscopic polyangiitis developed sudden abdominal pain and entered a state of shock. Abdominal CT showed massive hemoperitoneum, and emergent angiography revealed a ruptured splenic artery aneurysm. After direct catheterization attempts failed due to tortuous vessels and angiospasm, transcatheter arterial embolization using an n-butyl cyanoacrylate (NBCA)-lipiodol mixture was successfully performed. Fifty days later, the patient developed sudden abdominal pain again. Repeated angiography demonstrated recanalization of the splenic artery and splenic artery aneurysm. This time, the recanalized aneurysm was embolized using metallic coils with the isolation method. Physicians should keep in mind that recanalization can occur after transcatheter arterial embolization using N-butyl cyanoacrylate, which has been used as a permanent embolic agent.
Aging of Weapon Seals – An Update on Butyl O-ring Issues
Wilson, Mark H.
During testing under the Enhanced Surveillance Campaign in 2001, preliminary data detected a previously unknown and potentially serious concern with recently procured butyl o-rings on several programs. All butyl o-rings molded from a proprietary formulation throughout the period circa 1999 through 2001 had less than a full cure. Engineering judgment was that under curing is detrimental and could possibly lead to sub-optimum performance or, in the worst case, premature seal failure. An aging study was undertaken to ensure that suspect o-rings installed in the stockpile will retain sufficient sealing force for a minimum ten-year service life. A new prediction model developed for this study indicates suspect o-rings do not need to be replaced before the ten-year service life. Long-term testing results are reported on a yearly basis to validate the prediction model. This report documents the aging results for the period September 2002 to January 2011.
Batch polymerization of styrene and isoprene by n-butyl lithium initiator
Hasan, Sayeed
on these mechanisms Edgar (12) developed a mathema- tical model for polymerization of the above systems. In the present work polymerization reactions of styrene and isoprene via n-butyl lithium were studied at 80'C in n-hexane and cyclohexane solvents. Both... on the mechanisms proposed by Hsieh (18, 19, 20) Edgar (12) obtained an anlytical solution for calculating molecular weight di. stributions, monomer concentrations, initi. ator concentrations, and polymer species concentrations at any time, t, in a batch reactor...
Comprehensive testing to measure the response of butyl rubber to Hanford tank waste simulant
This report presents the findings of the Chemical Compatibility Program developed to evaluate plastic packaging components that may be incorporated in packaging mixed-waste forms for transportation. Consistent with the methodology outlined in this report, the authors performed the second phase of this experimental program to determine the effects of simulant Hanford tank mixed wastes on packaging seal materials. That effort involved the comprehensive testing of five plastic liner materials in an aqueous mixed-waste simulant. The testing protocol involved exposing the materials to {approximately}143, 286, 571, and 3,670 krad of gamma radiation and was followed by 7-, 14-, 28-, 180-day exposures to the waste simulant at 18, 50, and 60 C. Butyl rubber samples subjected to the same protocol were then evaluated by measuring seven material properties: specific gravity, dimensional changes, mass changes, hardness, compression set, vapor transport rates, and tensile properties. From the analyses, they determined that butyl rubber has relatively good resistance to radiation, this simulant, and a combination of these factors. These results suggest that butyl rubber is a relatively good seal material to withstand aqueous mixed wastes having similar composition to the one used in this study.
Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis
T.A. Semelsberger
The thermodynamic analyses of producing a hydrogen-rich fuel-cell feed from the process of dimethyl ether (DME) steam reforming were investigated as a function of steam-to-carbon ratio (0-4), temperature (100 C-600 C), pressure (1-5 atm), and product species: acetylene, ethanol, methanol, ethylene, methyl-ethyl ether, formaldehyde, formic acid, acetone, n-propanol, ethane and isopropyl alcohol. Results of the thermodynamic processing of dimethyl ether with steam indicate the complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide for temperatures greater than 200 C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure (P = 1 atm). Increasing the operating pressure was observed to shift the equilibrium toward the reactants; increasing the pressure from 1 atm to 5 atm decreased the conversion of dimethyl ether from 99.5% to 76.2%. The order of thermodynamically stable products in decreasing mole fraction was methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol--formaldehyde, formic acid, and acetylene were not observed. The optimal processing conditions for dimethyl ether steam reforming occurred at a steam-to-carbon ratio of 1.5, a pressure of 1 atm, and a temperature of 200 C. Modeling the thermodynamics of dimethyl ether hydrolysis (with methanol as the only product considered), the equilibrium conversion of dimethyl ether is limited. The equilibrium conversion was observed to increase with temperature and steam-to-carbon ratio, resulting in a maximum dimethyl ether conversion of approximately 68% at a steam-to-carbon ratio of 4.5 and a processing temperature of 600 C. Thermodynamically, dimethyl ether processed with steam can produce hydrogen-rich fuel-cell feeds--with hydrogen concentrations exceeding 70%. This substantiates dimethyl ether as a viable source of hydrogen for PEM fuel cells.
Kamil Klier; Richard G. Herman; Heock-Hoi Kwon; James G. C. Shen; Qisheng Ma; Robert A. Hunsicker; Andrew P. Butler; Scott J. Bollinger
A tungstena-zirconia (WZ) catalyst has been investigated for coupling methanol and isobutanol to unsymmetrical ethers, i.e. methyl isobutyl ether (MIBE) and compared with earlier studied sulfated-zirconia (SZ) and Nafion-H catalysts. In all cases, the ether synthesis mechanism is a dual site S{sub N}2 process involving competitive adsorption of reactants on proximal acid sites. At low reaction temperatures, methylisobutylether (MIBE) is the predominant product. However, at temperatures >135 C the WZ catalyst is very good for dehydration of isobutanol to isobutene. The surface acid sites of the WZ catalyst and a Nafion-H catalyst were diagnosed by high resolution X-ray photoelectron spectroscopy (XPS) of N 1s shifts after adsorption of amines. Using pyridine, ethylenediamine, and triethylamine, it is shown that WZ has heterogeneous strong Broensted acid sites. Theoretical study located the transition state of the alcohol coupling reaction on proximal Broensted acid sites and accounted well for XPS core-level shifts upon surface acid-base interactions. While computations have not been carried out with WZ, it is shown that the SZ catalyst is a slightly stronger acid than CF{sub 3}SO{sub 3}H (a model for Nafion-H) by 1.3-1.4 kcal/mol. A novel sulfated zirconia catalyst having proximal strong Broensted acid sites was synthesized and shown to have significantly enhanced activity and high selectivity in producing MIBE or isobutene from methanol/isobutanol mixtures. The catalyst was prepared by anchoring 1,2-ethanediol bis(hydrogen sulfate) salt precursor onto zirconium hydroxide, followed by calcination to remove the -(CH{sub 2}CH{sub 2})- bridging residues.
Dimethyl Ether Market Size | OpenEI Community
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A Potential Microhydro SiteDaytonDestilaria detheDiebuOpenDimethyl Ether
Host cells and methods for producing 3-methyl-2-buten-1-ol, 3-methyl-3-buten-1-ol, and 3-methyl-butan-1-ol
Chou, Howard H. (Berkeley, CA); Keasling, Jay D. (Berkeley, CA)
The invention provides for a method for producing a 5-carbon alcohol in a genetically modified host cell. In one embodiment, the method comprises culturing a genetically modified host cell which expresses a first enzyme capable of catalyzing the dephosphorylation of an isopentenyl pyrophosphate (IPP) or dimethylallyl diphosphate (DMAPP), such as a Bacillus subtilis phosphatase (YhfR), under a suitable condition so that 5-carbon alcohol is 3-methyl-2-buten-1-ol and/or 3-methyl-3-buten-1-ol is produced. Optionally, the host cell may further comprise a second enzyme capable of reducing a 3-methyl-2-buten-1-ol to 3-methyl-butan-1-ol, such as a reductase.
Alkaline stability of cellulose ethers and impact of their degradation products on cement hydration
Paris-Sud XI, Université de
1 Alkaline stability of cellulose ethers and impact of their degradation products on cement-mail address: firstname.lastname@example.com emse-00449712,version1-18Sep2010 Author manuscript, published in "Cement the potential role of cellulose ethers degradation on the alteration of the cement hydration kinetics
Decomposition of Ethanol and Dimethyl Ether During Chemical Vapour deposition Synthesis
Maruyama, Shigeo
1 Decomposition of Ethanol and Dimethyl Ether During Chemical Vapour deposition Synthesis of Single-phase thermal decomposition of ethanol and dimethyl ether (DME) at typical SWNT growth conditions using to the predicted decomposition mechanism. Signature peak intensities indicated concentrations of both ethanol
Effect of lower feedstock prices on economics of MTBE complex
Rahman, F.; Hamid, S.H.; Ali, M.A. [King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia)
Economic evaluation of the methyl tertiary butyl ether (MTBE) complex was carried out starting from n-butane and by captive production of methanol from natural gas. The processing steps consist of isomerization of n-butane to isobutane, dehydrogenation of isobutane to make isobutene, and finally, the reaction of isobutene with methanol to produce MTBE. Two different plant sizes were considered, and the effect of 30% lower feedback prices on profitability was studied. It was found that the raw materials cost is a dominant component, composing about 55% of the total production cost. An internal rate of return of 19% could be realized for 500,000 tons per annum MTBE complex based on economic data in mid-1993. The payback period estimated at this capacity was 3.8 years, and the break-even capacity was 36.6%.
The efficient use of natural gas in transportation
Stodolsky, F.; Santini, D.J.
Concerns over air quality and greenhouse gas emissions have prompted discussion as well as action on alternative fuels and energy efficiency. Natural gas and natural gas derived fuels and fuel additives are prime alternative fuel candidates for the transportation sector. In this study, we reexamine and add to past work on energy efficiency and greenhouse gas emissions of natural gas fuels for transportation (DeLuchi 1991, Santini et a. 1989, Ho and Renner 1990, Unnasch et al. 1989). We add to past work by looking at Methyl tertiary butyl ether (from natural gas and butane component of natural gas), alkylate (from natural gas butanes), and gasoline from natural gas. We also reexamine compressed natural gas, liquified natural gas, liquified petroleum gas, and methanol based on our analysis of vehicle efficiency potential. We compare the results against nonoxygenated gasoline.
The efficient use of natural gas in transportation
Stodolsky, F.; Santini, D.J.
Concerns over air quality and greenhouse gas emissions have prompted discussion as well as action on alternative fuels and energy efficiency. Natural gas and natural gas derived fuels and fuel additives are prime alternative fuel candidates for the transportation sector. In this study, we reexamine and add to past work on energy efficiency and greenhouse gas emissions of natural gas fuels for transportation (DeLuchi 1991, Santini et a. 1989, Ho and Renner 1990, Unnasch et al. 1989). We add to past work by looking at Methyl tertiary butyl ether (from natural gas and butane component of natural gas), alkylate (from natural gas butanes), and gasoline from natural gas. We also reexamine compressed natural gas, liquified natural gas, liquified petroleum gas, and methanol based on our analysis of vehicle efficiency potential. We compare the results against nonoxygenated gasoline.
Use TAME and heavier ethers to improve gasoline properties
Ignatius, J.; Jaervelin, H.; Lindqvist, P. (Neste Engineering, Porvoo (Finland))
Producing oxygenates from all potential FCC tertiary olefins is one of the most economic methods for reducing olefins and Reid vapor pressure (Rvp) in motor gasoline. MTBE production based on FCC isobutylene has reached a very high level. But the amount of MTBE from a refinery sidestream MTBE unit is insufficient for producing reformulated gasoline (RFG) and additional oxygenates must be purchased. The next phase will see conversion of isoamylenes in FCC light gasoline to TAME. Very little attention has been given to the heavier tertiary olefins present in the FCC light gasoline like tert-hexenes and heptenes. This route allows higher levels of oxygenates production, thereby lowering Rvp and the proportion of olefins in the gasoline pool and maximizing the use of FCC olefins. By using all the components produced by an FCC efficiently, many gasoline problems can be solved. Isobutene is converted to MTBE, C[sub 3]/C[sub 4] olefins are converted to alkylate and C[sub 5] tertiary olefins can be converted to TAME. All of these are preferred components for gasoline quality. By producing more oxygenates like MTBE, TAME and heavier ethers, a refinery can be self-sufficient in blending reformulated gasoline and no oxygenates need to be purchased. The technology for producing TAME and other ethers is described.
A kinetic investigation of the reaction of dibutyl sodiophosphonate with n-butyl bromide
Shaffer, James Howard
of Texn~ in partial fulfillment of the requirements for the de ree of MASTER OF SCIENCE August 1955 Major Subject: Chemistry A KINETIC INVESTIGATION OF THE REACTION OF DIBUTYL SODIOPHOSPHONATE WITH N-BUTYL BROMIDE A Thesis By James Howard Shaffer... Concentrations o " Reactants and Calculated Second Order Specific Reaction pa, ". ;e Rate Constants Table 1, 40 C Table 2, 50 0 Table 3, BO C 3c II. Initial Concentrations of React iit : ?d Apparent Rate Constants of Erofosed Die er 1!echani sm Table 4...
Dimethyl ether fuel proposed as an alternative to LNG
Kikkawa, Yoshitsugi; Aoki, Ichizo [Chiyoda Corp., Yokohama (Japan)
To cope with the emerging energy demand in Asia, alternative fuels to LNG must be considered. Alternative measures, which convert the natural gas to liquid fuel, include the Fischer-Tropsch conversion, methanol synthesis, and dimethyl ether (DME) synthesis. Comparisons are evaluated based on both transportation cost and feed-gas cost. The analysis will show that DME, one alternative to LNG as transportation fuel, will be more economical for longer distances between the natural-gas source and the consumer. LNG requires a costly tanker and receiving terminal. The break-even distance will be around 5,000--7,000 km and vary depending on the transported volume. There will be risk, however, since there has never been a DME plant the size of an LNG-equivalent plant [6 million metric tons/year (mty)].
Study of the peroxidation mechanism of diethyl ether (DEE) International Symposium on Loss Prvention
Paris-Sud XI, Université de
and in allylic and benzylic structures. In figure 23 are presented peroxidizable moieties in order of decreasing hazard. l.Ethers and acetals with a-hvdroaen H -i-o-
The Copolymerization of CO_(2) and Cyclic Ethers and Their Degradation Pathways
Wei, Sheng-Hsuan
couplings of epoxides and CO_(2) to produce polycarbonates has received attention from researchers. In this dissertation, metal catalyzed CO_(2)/cyclic ether copolymerization, depolymerization of polycarbonates, and the equilibria between polycarbonate...
Green polymer electrolytes based on chitosan and 1-butyl-3-methylimidazolium acetate
Shamsudin, Intan Juliana [Chemistry Department, Centre for Defence Foundation Studies, National Defence University of Malaysia, 57000 Kuala Lumpur (Malaysia); Ahmad, Azizan; Hassan, Nur Hasyareeda [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor Darul Ehsan (Malaysia)
Green polymer electrolytes based on chitosan as the polymer matrix and ionic liquid 1-butyl-3-methylimidazolium acetate [Bmim][OAc] as charge carriers were prepared by solution casting technique. Complexes with various amount of ionic liquid loading were investigated as possible ionic conducting polymers. The ionic conductivity was found to increase with increasing weight percent of ionic liquid. The highest ionic conductivity of the charged chitosan-[Bmim][OAc] was 2.44 × 10{sup ?3} S cm{sup ?1} at 90 wt.% of [Bmim][OAc] content at ambient temperature. Attenuated Total Reflection Fourier Transform infrared (ATR-FTIR) spectroscopy has proven the interaction between chitosan and [Bmim][OAc]. X-ray Diffraction (XRD) has shown that the amorphosity of the complexes increase as the amount of [Bmim][OAc] increase.
Photoelectric conversion and electrochromic properties of lutetium tetrakis(tert-butyl)bisphthalocyaninate
Hu, Andrew Teh; Hu Tenyi; Liu Lungchang
Both photoelectric and electrochromic effects on lutetium tetrakis(tert-butyl)bisphthalocyaninate (Lu(TBPc){sub 2}) have been carried out in this study. Lu(TBPc){sub 2} is known for its electrochromic performance, but its photoelectric effect has not mentioned in the literature. The electrochromic properties of Lu(TBPc){sub 2} have been measured by cyclic voltammetry (CV) and UV-Vis spectrometer at the same time. It takes less than 1.5 s for the color to change from red to green under 0.9 V. Its cycle life is at least over 500 times. Furthermore, we also investigate its photoelectric conversion properties. Its photoelectric cell exhibits a positive photo-electricity conversion effect with a short-circuit photocurrent (46.4 {mu}A/cm{sup 2}) under illumination of white light (1.201 mW/cm{sup 2})
Butyl rubber O-ring seals: Revision of test procedures for stockpile materials
Domeier, L.A.; Wagter, K.R.
Extensive testing showed little correlation between test slab and O-ring performance. New procedures, comparable to those used with the traditional test slabs, were defined for hardness, compression set, and tensile property testing on sacrificial O-ring specimens. Changes in target performance values were made as needed and were, in one case, tightened to reflect the O-ring performance data. An additional study was carried out on O-ring and slab performance vs cure cycle and showed little sensitivity of material performance to large changes in curing time. Aging and spectra of certain materials indicated that two sets of test slabs from current vendor were accidently made from EPDM rather than butyl rubber. Random testing found no O-rings made from EPDM. As a result, and additional spectroscope test will be added to the product acceptance procedures to verify the type of rubber compound used.
The Total Fatty Acids and Other Ether-Soluable Constituents of Feedstuffs.
Rather, J. B. (James Burness)
586-914-10m TEXAS AGRICULTURAL EXPERIMENT STATION BULLETIN NO. 169 SEPTEMBER, 19I4 DIVISION OF CHEMISTRY The Total Fatty Acids and Other Ether-Soluble Constituents of Feedstuffs BY J. B. RATHER Assistant Chemist POSTOFFICE COLLEGE STATION............................................................................................................. 5 An Improved Method for the Determination of Total Fatty Acids and Other Constituents of Ether Extracts................................... 7 A New Method for the Extraction of Total Fatty Acids and Other Constituents of Feed Stuffs...
Composition and Digestibility of the Ether Extract of Hays and Fodders.
Fraps, G. S.; Rather, J. B.
556-712-5m TEXAS AGRICULTURAL EXPERIMENT STATIONS. BULLETIN NO . 150 AUGUST , 1912. Division o f Chemistry TECHNICAL BULLETIN Composition and Digestibility of the Ether Extract of Hays and Fodders By G S. FRAPS and J. B. RATHER POSTOFFICE..........................................................13 Properties of UDsapoDifiable...................................................................15 Method of Determination of UDsapoDifiable and SapoDifiable........ 17 Composition of Ether Extract of Hays and Fodders........................ 21...
Bimetallic Ni-Rh catalysts with low amounts of Rh for the steam and autothermal reforming of n-butane for fuel-cell applications.
Ferrandon, M.; Kropf, A. J.; Krause, T.; Chemical Sciences and Engineering Division
Mono-metallic nickel and rhodium catalysts and bimetallic Ni-Rh catalysts supported on La-Al{sub 2}O{sub 3}, CeZrO{sub 2} and CeMgOx were prepared and evaluated for catalyzing the steam and autothermal reforming of n-butane. The binary Ni-Rh supported on La-Al{sub 2}O{sub 3} catalysts with low weight loading of rhodium exhibited higher H{sub 2} yields than Ni or Rh alone. The Ni-Rh/CeZrO{sub 2} catalyst exhibited higher performance and no coke formation, compared to the same metals on other supports. A NiAl{sub 2}O{sub 4} spinel phase was obtained on all Ni and Ni-Rh catalysts supported on La-Al{sub 2}O{sub 3}. The presence of rhodium stabilized the spinel phase as well as NiOx species upon reforming while Ni alone was mostly reduced into metallic species. Extended X-ray absorption fine-structure analysis showed evidence of Ni-Rh alloy during preparation and even further after an accelerated aging at 900C in a H{sub 2}/H{sub 2}O atmosphere.
Comparison of SPME headspace analysis to U.S. EPA method5030/8260B for MTBE monitoring
Stringfellow, William T.; Oh, Kuen-Chan
A novel method for analysis of methyl tert-butyl ether andtert-butyl alcohol using solid phase microextraction is described andcompared to a standard method.
Energy Efficiency Improvement and Cost Saving Opportunities for the Petrochemical Industry - An ENERGY STAR(R) Guide for Energy and Plant Managers
Neelis, Maarten
Ethylene dichloride 1 MTBE 2 Vinylchloride 3 Ethylbenzene 1Methyl- Tertiary-Butyl-Ether (MTBE) or Ethyl-Tertiary-Butyl-Styrene Vinylchloride MTBE Benzene, Toluene, Xylene Acetone
Treatability studies of groundwater contaminated with bis(2-chloroethyl) ether
Huang, F.Y.C. [New Mexico Inst. of Mining and Technology, Socorro, NM (United States). Dept. of Mineral and Environmental Engineering] [New Mexico Inst. of Mining and Technology, Socorro, NM (United States). Dept. of Mineral and Environmental Engineering; Li, K.Y.; Liu, C.C. [Lamar Univ., Beaumont, TX (United States). Dept. of Chemical Engineering] [Lamar Univ., Beaumont, TX (United States). Dept. of Chemical Engineering
The groundwater aquifer underneath a chemical manufacturing plant in Southeast Texas has been contaminated with the leachate from its landfill. There are 17 major chlorinated hydrocarbon contaminants found in the groundwater with concentrations ranging from 1 ppm to 1,200 ppm. An air-stripping unit followed by a thermal catalytic oxidation unit is currently operating on-site to remove all of the chlorinated compounds from the contaminated groundwater. One of the contaminants, bis(2-chloroethyl)ether (DCEE), has a fairly low Henry`s Law constant; therefore, a high air flow rate is employed in the stripping unit to improve the overall stripping efficiency. Nevertheless, the treated groundwater still contains a fair amount of DCEE. An UV-peroxidation reactor is set up to study its feasibility for oxidizing DCEE. The treatability data indicate that DCEE at a concentration of 200 ppm can be oxidized effectively in the presence of H{sub 2}O{sub 2} and the effective UV wavelengths lie between 200 and 280 nm. No noticeable reduction of the oxidation rate is observed at low temperature ({approximately} 11 C). Apparent oxidation rate equations of DCEE are determined and several process design parameters are discussed.
An Explanation of Dayton Miller's Anomalous "Ether Drift" Result
Thomas J. Roberts
In 1933 Dayton Miller published in this journal the results of his voluminous observations using his ether drift interferometer, and proclaimed that he had determined the "absolute motion of the earth". This result is in direct conflict with the prediction of Special Relativity, and also with numerous related experiments that found no such signal or "absolute motion". This paper presents a complete explanation for his anomalous result by: a) showing that his results are not statistically significant, b) describing in detail how flaws in his analysis procedure produced a false signal with precisely the properties he expected, and c) presenting a quantitative model of his systematic drift that shows there is no real signal in his data. In short, this is every experimenter's nightmare: he was unknowingly looking at statistically insignificant patterns in his systematic drift that mimicked the appearance of a real signal. An upper limit on "absolute motion" of 6 km/sec is derived from his raw data, fully consistent with similar experimental results and the prediction of Special Relativity. The key point of this paper is the need for a comprehensive and quantitative error analysis. The concepts and techniques used in this analysis were not available in Miller's day, but are now standard. These problems also apply to the famous measurements of Michelson and Morley, and to most if not all similar experiments; appendices are provided discussing several such experiments.
Vapor-liquid equilibria for methanol + tetraethylene glycol dimethyl ether
Esteve, X.; Chaudhari, S.K.; Coronas, A. [Univ. Rovira i Virgili, Tarragona (Spain). Dept. of Electrical and Mechanical Engineering
Vapor-liquid equilibrium (P-T-x) for the methanol + tetraethylene glycol dimethyl ether binary system were obtained by the static method in the range of temperatures from 293.15 to 423.15 K at 10 K intervals. The modified vapor pressure apparatus used is described. The Kuczynsky method was used to calculate the liquid and vapor composition and the activity coefficients of methanol from the initial composition of the sample and the measured pressure and temperature. The results were correlated by the NRTL and UNIQUAC temperature dependent activity coefficient models. This system shows nearly ideal behavior at 323.15 K, but positive deviations from ideality at lower temperatures and negative deviations at higher temperatures are observed. The activity coefficients become more negative with the increase in temperature and mole fraction of methanol. The excess molar enthalpy using the Gibss-Helmholtz equation and the NRTL and UNIQUAC parameters were calculated at 303.15 K and compared with experimental data. This binary system shows promise as a working pair for high-temperature heat pump applications.
Economics for iso-olefin production using the fluid catalytic cracking unit
McClung, R.G.; Witoshkin, A.; Bogert, D.C.; Winkler, W.S. [Englehard Corp., Iselin, NJ (United States)
The Clean Air Act of 1990 requires use of oxygenates in some gasolines to improve both CO and hydrocarbon auto tailpipe emissions. Various oxygenates are currently being used by the refining industry. For the fully integrated refinery having a fluid catalytic cracking unit, the most commonly used oxygenates are methyl tertiary butyl ether (MTBE) and tertiary amyl ether (TAME). The FCC unit produces the isobutylene and iso-amylases need for manufacture of both MTBE and TAME. The economics for an assumed refinery processing scheme for several FCC cases are examined giving estimates of income and investments for each case. Up to one-third of the total gasoline pool can be made in reformulated gasoline using TAME and MTBE with the FCC unit as the sole source of feedstock. This processing route is much more economical than the alternative scheme using butane isomerization/iosbutane dehydrogenation.
Anhydrous aluminum chloride as an alkylation catalyst: identification of mono- and dialkyl-benzenes from the condensation of tertiary butyl alcohol with benzene.
Scoggins, Lacey E
LIBRARY a a w c"I. I. SI - O~ TI:YAf ANHYDROUS ALUMINUM CHLORIDE AS AN ALKYLATION CATALYST: IDENTIFICATION OF MONO- AND DIALKYIZENZENES FROM THE CONDENSATION QF TERTIARY BUTYL ALCOHOL WITH BENKENE IACEY EUGENE SCOGGINS 4 A Thesis Submitted...: IDENTIFICATION OF MONO- AND DI~NZZNES FROM THE CONDENSATION OF TERTIARY BUTYL ALCOHOL WITH BENZENE A Thesis By LACEY EUGENE SCOGGINS Approved as to style and content hy: Chairman of Committee Head of Chemistry Department 1959 ACKNOWLEDGME1VTS The author...
Elana M. Chapman; Shirish Bhide; Jennifer Stefanik; Howard Glunt; Andre L. Boehman; Allen Homan; David Klinikowski
The objectives of this research and demonstration program are to convert a campus shuttle bus to operation on dimethyl ether, a potential ultra-clean alternative diesel fuel. To accomplish this objective, this project includes laboratory evaluation of a fuel conversion strategy, as well as, field demonstration of the DME-fueled shuttle bus. Since DME is a fuel with no lubricity (i.e., it does not possess the lubricating quality of diesel fuel), conventional fuel delivery and fuel injection systems are not compatible with dimethyl ether. Therefore, to operate a diesel engine on DME one must develop a fuel-tolerant injection system, or find a way to provide the necessary lubricity to the DME. In this project, they have chosen the latter strategy in order to achieve the objective with minimal need to modify the engine. Their strategy is to blend DME with diesel fuel, to obtain the necessary lubricity to protect the fuel injection system and to achieve low emissions. The bulk of the efforts over the past year were focused on the conversion of the campus shuttle bus. This process, started in August 2001, took until April 2002 to complete. The process culminated in an event to celebrate the launching of the shuttle bus on DME-diesel operation on April 19, 2002. The design of the system on the shuttle bus was patterned after the system developed in the engine laboratory, but also was subjected to a rigorous failure modes effects analysis (FMEA, referred to by Air Products as a ''HAZOP'' analysis) with help from Dr. James Hansel of Air Products. The result of this FMEA was the addition of layers of redundancy and over-pressure protection to the system on the shuttle bus. The system became operational in February 2002. Preliminary emissions tests and basic operation of the shuttle bus took place at the Pennsylvania Transportation Institute's test track facility near the University Park airport. After modification and optimization of the system on the bus, operation on the campus shuttle route began in early June 2002. However, the work and challenges continued as it has been difficult to maintain operability of the shuttle bus due to fuel and component difficulties. In late June 2002, the pump head itself developed operational problems (loss of smooth function) leading to excessive stress on the magnetic coupling and excessive current draw to operate. A new pump head was installed on the system to alleviate this problem and the shuttle bus operated successfully on DME blends from 10-25 vol% on the shuttle bus loop until September 30, 2002. During the period of operation on the campus loop, the bus was pulled from service, operated at the PTI test track and real-time emissions measurements were obtained using an on-board emissions analyzer from Clean Air Technologies International, Inc. Particulate emissions reductions of 60% and 80% were observed at DME blend ratios of 12 vol.% and 25 vol.%, respectively, as the bus was operated over the Orange County driving cycle. Increases in NOx, CO and HC emissions were observed, however. In summary, the conversion of the shuttle bus was successfully accomplished, particulate emissions reductions were observed, but there were operational challenges in the field. Nonetheless, they were able to demonstrate reliable operation of the shuttle bus on DME-diesel blends.
Features of the spectral dependences of transmittance of organic semiconductors based on tert-butyl substituted lutetium phthalocyanine molecules
Belogorokhov, I. A., E-mail: firstname.lastname@example.com [State Research and Project Institute of Rare-Metal Industry GIREDMET (Russian Federation); Tikhonov, E. V. [Moscow State University (Russian Federation); Dronov, M. A. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Belogorokhova, L. I. [Moscow State University (Russian Federation); Ryabchikov, Yu. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Tomilova, L. G.; Khokhlov, D. R. [Moscow State University (Russian Federation)
Vibronic properties of organic semiconductors based on tert-butyl substituted phthalocyanine lutetium diphthalocyanine molecules are studied by IR and Raman spectroscopy. It is shown that substitution of several carbon atoms in initial phthalocyanine (Pc) ligands with {sup 13}C isotope atoms causes a spectral shift in the main absorption lines attributed to benzene, isoindol, and peripheral C-H groups. A comparison of spectral characteristics showed that the shift can vary from 3 to 1 cm{sup -1}.
Transcatheter Arterial Embolization of Intramuscular Active Hemorrhage with N-Butyl Cyanoacrylate
Yoo, Dong Hyun; Jae, Hwan Jun, E-mail: email@example.com; Kim, Hyo-Cheol; Chung, Jin Wook; Park, Jae Hyung [Seoul National University College of Medicine, Clinical Research Institute, Seoul National University Hospital, Department of Radiology, and Institute of Radiation Medicine (Korea, Republic of)
Purpose: This study was designed to evaluate the clinical efficacy and safety of transcatheter arterial embolization (TAE) with n-butyl cyanoacrylate (NBCA) for intramuscular active hemorrhage of varied etiologies and anatomic sites. Methods: Eighteen patients who demonstrated hematoma with pseudoaneurysm and/or active extravasation of contrast media underwent TAE with NBCA. Etiologies of hematoma included trauma, postoperative complication, and coagulopathy (due to underlying disease or anticoagulation therapy). Sites of embolization included chest wall, abdomen wall, retroperitoneum, and extremity. TAE was performed by using 1:3 to 1:5 mixtures of NBCA and iodized oil, either solely (n = 15) or in combination with microcoil (n = 3). The technical and clinical success rate, procedure-related complications, and clinical outcomes were evaluated. Results: The technical and clinical success rates were 100% and 83% (15/18), respectively. Two patients expired while admitted due to other comorbidities. One patient expired due to recurrent bleeding at another site. There were no serious complications relating to the embolization procedure. Conclusions: TAE with NBCA is effective and safe treatment modality for intramuscular active hemorrhage.
Multiprobe Spectroscopic Evidence for "Hyperpolarity" within 1-Butyl-3-methylimidazolium Hexafluorophosphate Mixtures with Tetraethylene Glycol
Sarkar, Abhra [Indian Institute of Technology, Delhi; Trivedi, Shruti [Indian Institute of Technology, Delhi; Baker, Gary A [ORNL; Pandey, Siddharth [Indian Institute of Technology, Delhi
A hybrid, potentially green solvent system composed of tetraethylene glycol (TEG) and the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) was investigated across all mole fractions with regard to the solvent properties of the mixture. For this purpose, a suite of absorbance- and fluorescence-based solvatochromic probes were utilized to explore solute-solvent and solvent-solvent interactions existing within the [bmim][PF6] + TEG system. These studies revealed an interesting and unusual synergistic solvent effect. In particular, a remarkable hyperpolarity was observed in which the ET value, comprising dipolarity/polarizability and hydrogen bond donor (HBD) acidity contributions, at intermediate mole fractions of the binary mixture well exceeded that of the most polar pure component (i.e., [bmim][PF6]). Independently determined dipolarity/polarizability ( *) and HBD acidity (R) Kamlet-Taft values for the [bmim][PF6] + TEG mixtures were also observed to be anomalously high at intermediate mole fractions, whereas hydrogen bond acceptor (HBA) basicities ( values) were much more in line with the ideal arithmetic values predicted on a mole fraction basis.
The Scientific Basis for the Regulation of Nanoparticles: Challenging Paracelsus and Pare
Goldstein, Bernard D.
NANOTECHNOILOGY 402 (2007). 20. MTBE unquestionably causesTertiary-Butyl Ether (MTBE)-a Gasoline Additive-CausesMethyl Tertiary-butyl Ether (MTBE) in CD-I Mice and F-344
-butyl ether (MTBE) on urban particles indicates a site- specific interaction between MTBE and a particulate is a possible source only for the gasoline oxygenate methyl tert-butyl ether (MTBE). Lopes and Bender (1998
Life-cycle Environmental Inventory of Passenger Transportation in the United States
Chester, Mikhail V
Methyl tert?Butyl Ether (MTBE); http://www.atsdr.cdc.gov/Methyl Tertiary Butyl Ether (MTBE), which was easily accounting was not performed on MTBE and the result of
Measurement and Treatment of Nuisance Odors at Wastewater Treatment Plants
Abraham, Samantha Margaret
in the presence of MTBE, ETBE and TAME. Chemosphere 85, 616-Xanthomonas sp. MTBE/ETBE/TAME a Acinetobacter calcoaceticusMTBE= Methyl tert-Butyl Ether, ETBE= Ethyl tert-Butyl Ether,
Atmos. Chem. Phys., 6, 21612176, 2006 www.atmos-chem-phys.net/6/2161/2006/
Meskhidze, Nicholas
is oxygenated by addition of ethyl-tertio-butyl ether (ETBE), the second is based on a reformulation of its the ethyl- tertio-butyl-ether or ETBE) allows the
Catalyst system and process for benzyl ether fragmentation and coal liquefaction
Zoeller, Joseph Robert (Kingsport, TN)
Dibenzyl ether can be readily cleaved to form primarily benzaldehyde and toluene as products, along with minor amounts of bibenzyl and benzyl benzoate, in the presence of a catalyst system comprising a Group 6 metal, preferably molybdenum, a salt, and an organic halide. Although useful synthetically for the cleavage of benzyl ethers, this cleavage also represents a key model reaction for the liquefaction of coal; thus this catalyst system and process should be useful in coal liquefaction with the advantage of operating at significantly lower temperatures and pressures.
Toxicity of polychlorinated diphenyl ethers in Hydra attenuata and in rat whole embryo culture
Becker, Marion Carol
TOXICITY OF POLYCHLORINATED DIPHENYL ETHERS IN HYDRA A?TENUATA AND IN RAT WHOLE EMBRYO CULTURE A Thesis by MARION CAROL BECKER Submitted to the Office of Graduate Studies of Texas A8cM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May 1991 Major Subject: Toxicology TOXICITY OF POLYCHLORINATED DIPHENYL ETHERS IN HYDRA A1TENUATA AND IN RAT WHOLE EMBRYO CULTURE by MARION CAROL BECKER Approved as to style and content by: Stephen H. S (Ca...
Toxicity of polychlorinated diphenyl ethers in Hydra attenuata and in rat whole embryo culture
Becker, Marion Carol
TOXICITY OF POLYCHLORINATED DIPHENYL ETHERS IN HYDRA A?TENUATA AND IN RAT WHOLE EMBRYO CULTURE A Thesis by MARION CAROL BECKER Submitted to the Office of Graduate Studies of Texas A8cM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May 1991 Major Subject: Toxicology TOXICITY OF POLYCHLORINATED DIPHENYL ETHERS IN HYDRA A1TENUATA AND IN RAT WHOLE EMBRYO CULTURE by MARION CAROL BECKER Approved as to style and content by: Stephen H. S (Ca...
Vol. 83, No. 2, 2006 121 Analysis of Heat Transfer Fouling by Dry-Grind Maize Thin Stillage
-tertiary butyl ether (MTBE), a petroleum derivative, and ethanol. In recent years, MTBE has been phased out due
MTBE Production Economics (Released in the STEO April 2001)
Reports and Publications (EIA)
The purpose of this analysis is to evaluate the causes of methyl tertiary butyl ether (MTBE) price increases in 2000.
Characterization of trace gases measured over Alberta oil sands mining operations: 76 speciated C2-C10 volatile organic compounds (VOCs), CO2, CH4, CO, NO, NO2, NOy, O3 and SO2
K. : Atmospheric chemistry of gasoline-related emissions:chemistry. Methyl tert-butyl ether is a solvent and gasoline
The social costs of an MTBE ban in California (Long version)
Rausser, Gordon C.; Adams, Gregory D.; Montgomery, W. David; Smith, Anne E.
ethyl tertiary-butyl ether (ETBE) or tertiary amyl methylOther oxygenates, such as ETBE and TAME exist. However,
The Social Costs of an MTBE Ban in California
Rausser, Gordon C.; Adams, Gregory D.; Montgomery, W. David; Smith, Anne E.
ethyl tertiary butyl ether (ETBE), or tertiary amyl methylOther oxygenates such as ETBE and TAME exist. However, these
Health risks associated with exposure to gasoline additives-methyl tertiary butyl ether [MTBE]. Hearing before a Subcommittee of the Committee on Appropriations, United States Senate, One Hundred Third Congress, First Session, Special Hearing
Not Available
This hearing focuses on an Alaskan study by the Centers for Disease Control which examines possible health risks associated with exposure to gasoline additive know as MTBE. Testimony is given by Dr. William Roper, Director, CDC.
Effect of thermal history on the molecular orientation in polystyrene/poly(vinyl methyl ether) blends
Pezolet, Michel
ether) (PS/PVME) has been studied using polarization modulation infrared linear dichroism (PM to an increased orientation if the heating time at 51 8C is kept short. Moreover, PS and PVME develop a larger) blends; Thermal history; Polarization modulation infrared linear dichroism 1. Introduction The influence
NMR investigations of water retention mechanism by cellulose ethers in cement-based materials
Boyer, Edmond
1 NMR investigations of water retention mechanism by cellulose ethers in cement-based materials J of freshly-mixed white cement pastes. NMRD is useful to determine the surface diffusion coefficient of water, the specific surface area and the hydration kinetics of the cement-based material. In spite of modifications
Dimethyl ether (DME) from coal as a household cooking fuel in China
be made from any carbonaceous feedstock, including natural gas, coal, or biomass, using establishedDimethyl ether (DME) from coal as a household cooking fuel in China Eric D. Larson Princeton gas (LPG) as a household cooking fuel. As such, DME is an attractive fuel for clean cooking. DME can
Lithium Hexamethyldisilazide-Mediated Ketone Enolization: The Influence of Hindered Dialkyl Ethers and Isostructural
Collum, David B.
Lithium Hexamethyldisilazide-Mediated Ketone Enolization: The Influence of Hindered Dialkyl Ethers of the enolization of 2-methylcyclohexanone mediated by lithium hexameth- yldisilazide (LiHMDS; TMS2NLi) solvated- bine to make lithium hexamethyldisilazide (LiHMDS) one of the most important Bro¨nsted bases in organic
Viscoelastic Behavior of Poly(ether imide) Incorporated with Multiwalled Carbon Nanotubes
Fisher, Frank
plastic, and suitable for use in many demanding applications because of its relatively high strength, high, and thermal properties of engineering plastics, including poly(ether imide) (PEI), with various nanoin; viscoelastic properties INTRODUCTION The demand for lightweight materials with high strength and thermal
Unexpected Alternated Radical Copolymerization of Vinylidene cyanide with a Vinyl ether for Superhydrophobic and Highly
Paris-Sud XI, Université de
for Superhydrophobic and Highly Oleophobic Films Ahmed Meskini, Mustapha Raihane Laboratoire de Chimie Bioorganique et Radical Copolymerization of Vinylidene cyanide with a Vinyl ether for Superhydrophobic and Highly(VCN-alt-FAVE8) copolymers exhibit superhydrophobic and highly oleophobic characters as evidenced by high water
Assessment of ether and alcohol fuels from coal. Volume 2. Technical report
Not Available
A unique route for the indirect liquefaction of coal to produce transportation fuel has been evaluated. The resultant fuel includes alkyl tertiary alkyl ethers and higher alcohols, all in the gasoline boiling range. When blended into gasoline, the ether fuel provides several advantages over the lower alcohols: (1) lower chemical oxygen content, (2) less-severe water-separation problems, and (3) reduced front-end volatility effects. The ether fuel also has high-octane quality. Further, it can be utilized as a gasoline substitute in all proportions. Production of ether fuel combines several steps, all of which are or have been practiced on an industrial scale: (1) coal gasification, (2) gas cleanup and shift to desired H/sub 2/:CO ratio, (3) conversion of synthesis gas to isobutanol, methanol, and higher alcohols, (4) separation of alcohols, (5) chemical dehydration of isobutanol to isobutylene, and (6) etherification of isobutylene with methanol. A pilot-plant investigation of the isobutanol synthesis step was performed. Estimates of ether-fuel manufacturing costs indicate this process route is significantly more costly than synthesis of methanol. However, the fuel performance features provide incentive for developing the necessary process and catalyst improvements. Co-production of higher-molecular-weight co-solvent alcohols represents a less-drastic form of methanol modification to achieve improvement in the performance of methanol-gasoline blends. Costs were estimated for producing several proportions of methanol plus higher alcohols from coal. Estimated fuel selling price increases regularly but modestly with higher alcohol content.
Radical-anions of aromatic compounds. VII. Reaction of the products from the reduction of nitrobenzene by sodium with isopropyl and tert-butyl iodides
Danilova, N.K.; Shteingarts, V.D.
The reaction of the products from the reduction of nitrobenzene by one and two equivalents of sodium with isopropyl iodide leads to the formation of N,O-diisopropylphenylhydroxylamine, while the reaction with tert-butyl iodide leads to p-(tert-butyl)nitrobenzene. Such a change in the nature of the reaction product in the transition from the primary and secondary alkyl halides to the tertiary alkyl halides clearly results from a change in the S/sub N/2 mechanism to the S/sub RN/1 mechanism, involving transfer of an electron from the radical-anion or dianion of nitrobenzene to the alkyl halide. The formation of considerable amounts of azoxybenzene in the reaction with tert-butyl iodide shows that the dianion and, to a lesser degree, the radical-anion of nitrobenzene exhibit basic characteristics.
Molecular Simulation of Water Extraction into a Tri-n-Butyl-Phosphate/n-Dodecane Solution
de Almeida, Valmor F [ORNL] [ORNL; Ye, Xianggui [ORNL] [ORNL; Cui, Shengting [ORNL] [ORNL; Khomami, Bamin [ORNL] [ORNL
Abstract: Molecular dynamics simulations were performed to investigate water extraction into a solution of 30 vol% tri-n-butyl-phosphate (TBP) in n-dodecane. This solvent extraction mixture is commonly used in hydrometallurgical and nuclear fuel recycling operations for recovering metals from aqueous streams. It is known that water is coextracted in the organic phase and that it competes with metal ions for the available extractant agent (TBP). Therefore investigating pure water extraction provides a realistic prototype to test molecular simulation methods for the first time in this area. Our computational results indicate that the TBP electric dipole moment has a significant effect on the predicted water solubility. A larger TBP dipole moment decreases the aqueous-organic interfacial tension, leading to increased roughness of the aqueous-organic interface. Interfacial roughness has a significant effect on disrupting the interfacial water hydrogen bonding structure, resulting in a greater number of dangling water molecules at the interface. This enhances the probability of water molecules to break away from the aqueous phase and to migrate into the bulk of the organic phase. Therefore, the magnitude of the TBP dipole moment is a crucial factor in controlling water hydrogen bond breaking at the aqueous-organic interface. By slightly lowering the atomic partial charges of the TBP atoms, to produce a dipole moment that better agrees with experimental data, we were able to predict water solubility in close agreement with experimental measurements. Hence we demonstrate that a molecular modeling and simulation approach may provide quantitative support to experimental programs in this area. In addition, our simulation results shed light into the molecular mechanism of water extraction, the critical role of TBP, and the structural forms of water molecules both at the interface and in the bulk of the organic phase. Specifically, it is found that water molecules are extracted either as single molecules or as clusters. Furthermore, within the organic phase, the extracted water forms clusters with up to 20 water molecules, however, more than 70% of these water clusters contain less than 5 water molecules when the water extraction process reaches saturation.
An evaluation of the 3M Organic Vapor Monitor #3500 as a short term exposure limit sampling device for acetone, methyl ethyl ketone, and methyl iso butyl ketone
Andrew, Lloyd B.
AN EVALUATION OF THE 3M ORGANIC VAPOR MONITOR 43500 AS A SHOR'I TERM EXPOSURE LIMIT SAMPLING DEVICE FOR ACETONE, METHYL ETHYL KETONE, AND METHYL ISO BUTYL KETONE A Thesis by LLOYD B. ANDREW III Submitted to the Graduate College of Texas ASM..., METHYL ETHYL KETONE, AND METHYL ISO BUTYL KETONE A Thesis by Lloyd B. Andrew III Approved as to style and content by: (Chai iy' of Co ' i tee) (He of Departme t) e4mY ~. (Member) C~& n (Member) December 1982 ABSTRACT An Evaluation of the 3M...
Role of the reaction intermediates in determining PHIP (parahydrogen induced polarization) effect in the hydrogenation of acetylene dicarboxylic acid with the complex [Rh (dppb)]{sup +} (dppb: 1,4-bis(diphenylphosphino)butane)
Reineri, F.; Aime, S. [Department of Molecular Biotechnologies and Health Sciences, University of Torino, Via Nizza 52, 10123 Torino (Italy)] [Department of Molecular Biotechnologies and Health Sciences, University of Torino, Via Nizza 52, 10123 Torino (Italy); Gobetto, R.; Nervi, C. [Department of Chemistry, University of Torino, via P. Giuria 7, 10125 Torino (Italy)] [Department of Chemistry, University of Torino, via P. Giuria 7, 10125 Torino (Italy)
This study deals with the parahydrogenation of the symmetric substrate acetylene dicarboxylic acid catalyzed by a Rh(I) complex bearing the chelating diphosphine dppb (1,4-bis(diphenylphosphino)butane). The two magnetically equivalent protons of the product yield a hyperpolarized emission signal in the {sup 1}H-NMR spectrum. Their polarization intensity varies upon changing the reaction solvent from methanol to acetone. A detailed analysis of the hydrogenation pathway is carried out by means of density functional theory calculations to assess the structure of hydrogenation intermediates and their stability in the two solvents. The observed polarization effects have been accounted on the basis of the obtained structures. Insights into the lifetime of a short-lived reaction intermediate are also obtained.
Process to convert biomass and refuse derived fuel to ethers and/or alcohols
Diebold, J.P.; Scahill, J.W.; Chum, H.L.; Evans, R.J.; Rejai, B.; Bain, R.L.; Overend, R.P.
A process is described for conversion of a feedstock selected from the group consisting of biomass and refuse derived fuel (RDF) to provide reformulated gasoline components comprising a substantial amount of materials selected from the group consisting of ethers, alcohols, or mixtures thereof, comprising: drying said feedstock; subjecting said dried feedstock to fast pyrolysis using a vortex reactor or other means; catalytically cracking vapors resulting from said pyrolysis using a zeolite catalyst; condensing any aromatic byproduct fraction; catalytically alkylating any benzene present in said vapors after condensation; catalytically oligomerizing any remaining ethylene and propylene to higher olefins; isomerizing said olefins to reactive iso-olefins; and catalytically reacting said iso-olefins with an alcohol to form ethers or with water to form alcohols. 35 figs.
Process to convert biomass and refuse derived fuel to ethers and/or alcohols
Diebold, James P. (Lakewood, CO); Scahill, John W. (Evergreen, CO); Chum, Helena L. (Arvada, CO); Evans, Robert J. (Lakewood, CO); Rejai, Bahman (Lakewood, CO); Bain, Richard L. (Golden, CO); Overend, Ralph P. (Lakewood, CO)
A process for conversion of a feedstock selected from the group consisting of biomass and refuse derived fuel (RDF) to provide reformulated gasoline components comprising a substantial amount of materials selected from the group consisting of ethers, alcohols, or mixtures thereof, comprising: drying said feedstock; subjecting said dried feedstock to fast pyrolysis using a vortex reactor or other means; catalytically cracking vapors resulting from said pyrolysis using a zeolite catalyst; condensing any aromatic byproduct fraction; catalytically alkylating any benzene present in said vapors after condensation; catalytically oligomerizing any remaining ethylene and propylene to higher olefins; isomerizing said olefins to reactive iso-olefins; and catalytically reacting said iso-olefins with an alcohol to form ethers or with water to form alcohols.
solved in an organic solvent and diethyl ether was the most appropriate. The solvent
Paris-Sud XI, Université de
, the growth was hampe- red by a too large portion of wax. For detecting spores in beeswax, the wax was put into water (wax/water 1:10). The receptacle was placed into a water bath hea- ted up to 90 °C for 6 min, under the wax dissolved in diethyl ether. 80 ?L of this solution was smeared onto a plate with MYP
2[prime] and 3[prime] Carboranyl uridines and their diethyl ether adducts
Soloway, A.H.; Barth, R.F.; Anisuzzaman, A.K.; Alam, F.; Tjarks, W.
A process is described for preparing carboranyl uridine nucleoside compounds and their diethyl ether adducts, which exhibit a tenfold increase in boron content over prior art boron containing nucleoside compounds. The carboranyl uridine nucleoside compounds exhibit enhanced lipophilicity and hydrophilic properties adequate to enable solvation in aqueous media for subsequent incorporation of the compounds in methods for boron neutron capture therapy in mammalian tumor cells. No Drawings
Molecular modeling of the morphology and transport properties of two direct methanol fuel cell membranes: phenylated sulfonated poly(ether ether ketone ketone) versus Nafion
Devanathan, Ramaswami; Idupulapati, Nagesh B.; Dupuis, Michel
We have used molecular dynamics simulations to examine membrane morphology and the transport of water, methanol and hydronium in phenylated sulfonated poly ether ether ketone ketone (Ph-SPEEKK) and Nafion membranes at 360 K for a range of hydration levels. At comparable hydration levels, the pore diameter is smaller, the sulfonate groups are more closely packed, the hydronium ions are more strongly bound to sulfonate groups, and the diffusion of water and hydronium is slower in Ph-SPEEKK relative to the corresponding properties in Nafion. The aromatic carbon backbone of Ph-SPEEKK is less hydrophobic than the fluorocarbon backbone of Nafion. Water network percolation occurs at a hydration level ({lambda}) of {approx}8 H{sub 2}O/SO{sub 3}{sup -}. At {lambda} = 20, water, methanol and hydronium diffusion coefficients were 1.4 x 10{sup -5}, 0.6 x 10{sup -5} and 0.2 x 10{sup -5} cm{sup 2}/s, respectively. The pore network in Ph-SPEEKK evolves dynamically and develops wide pores for {lambda} > 20, which leads to a jump in methanol crossover and ion transport. This study demonstrates the potential of aromatic membranes as low-cost challengers to Nafion for direct methanol fuel cell applications and the need to develop innovative strategies to combat methanol crossover at high hydration levels.
Successful Pregnancy with a Full-Term Vaginal Delivery One Year After n-Butyl Cyanoacrylate Embolization of a Uterine Arteriovenous Malformation
McCormick, Colleen C. [Johns Hopkins University School of Medicine, Department of Gynecology and Obstetrics (United States); Kim, Hyun S. [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science (United States)], E-mail: email@example.com
Uterine arteriovenous malformation (AVM) causes significant morbidity with vaginal bleeding. Traditional therapy is a hysterectomy with no potential for future pregnancy. We present a case of successful superselective embolization of uterine AVM using n-butyl cyanoacrylate with subsequent normal term pregnancy and uncomplicated vaginal delivery in 1 year.
Autoignition behavior of lean mixtures: Chemical and thermodynamics effects
Ronney, P.D.; Shoda, M.; Waida, S.T. [Princeton Univ., NJ (United States). Dept. of Mechanical and Aerospace Engineering; Westbrook, C.K.; Pitz, W.J. [Lawrence Livermore National Lab., CA (United States)
Knock characteristics of natural gas (NG), 89 octane unleaded gasoline, 2,2-dimethyl butane (22DMB), and methyl tert-butyl ether (MTBE) in stoichiometric and lean fuel-air mixtures were studied in a production 4-cylinder automotive engine. The Intake Temperature at the Knock Limit (ITKL) was different for each fuel but always higher in lean mixtures. Gasoline and 22DMB exhibited much greater increases in ITKL than MTBE and NG at lean conditions. Surprisingly, for lean mixtures 22DMB exhibited higher ITKL than MTBE and was almost as high as NG. Comparison with detailed numerical modelling was very favorable. Computations show that both differences in chemistry and end-gas temperature and pressure histories are responsible for these trends. This behavior is interpreted in terms of the Negative Temperature Coefficient behavior of hydrocarbon oxidation. The implication of these results for the specification of optimal fuels for lean-burn engine is discussed.
Lyondell develops one step isobutylene process
Not Available
This paper reports that Lyondell Petrochemical Co., Houston, has developed a one step process to convert normal butylenes to isobutylene, a key component of methyl tertiary butyl ether (MTBE). MTBE is expected to become the additive of choice among U.S. refiners to blend oxygenated gasolines required by 1990 amendments to the Clean Air Act. Lyondell Pres. and Chief Executive Officer Bob Gower the the new process could help assure adequate supplies of MTBE to meet U.S. demand for cleaner burning fuels. Lyondell estimates the capital cost of building a grassroots plant to produce isobutylene with the new process would be less than half the cost of a grassroot plant to produce isobutylene with existing technology starting with normal butane.
High octane ethers from synthesis gas-derived alcohols. Quarterly technical progress report, April--June 1993
Klier, K.; Herman, R.G.; Menszak, J.; Johansson, M.A.; Feeley, O.C.; Kim, D.
The results shown in Figures 10 and 11 demonstrate that the formation of butenes was very sensitive to the alcohol partial pressure. A small elevation of the alcohol pressure suppressed the formation of butenes rather drastically at both 90 and 117{degree}C. The synthesis rates of DME, MIBE, and MTBE ethers were not significantly affected at 90{degree}C, although there was a trend to increase the space time yield of DME as the alcohol pressure was increased. At the reaction temperature of 117{degree}C, all of the ethers showed increasing productivities as the pressure of the reactants was increased (Figure 11). An isotope labelling experiment was carried out to provide mechanistic insight into the manner in which methanol and isobutanol react together to form DME, MIBE, and MTBE ethers and to determine if MTBE were derived from MIBE.
Impact of cellulose ethers on the cement paste microstructure J. Pourchez*, P. Grosseau*, E. Rouche-Pourchez*, J. Debayle*, J.C. Pinoli*,
Paris-Sud XI, Université de
Impact of cellulose ethers on the cement paste microstructure J. Pourchez*, P. Grosseau*, E to examine the effects of cellulose ethers on the cement paste microstructure. The obtained results show, the content of air volume and the stabilisation of the porosity from the fresh cement paste to the hardened
Use of ferric sulfate: acid media for the desulfurization of model compounds of coal. [Dibenzothiophene, diphenyl sulfide, di-n-butyl sulfide
Clary, L.R.; Vermeulen, T.; Lynn, S.
The objective of this work has been to investigate the ability of ferric sulfate-acid leach systems to oxidize the sulfur in model compounds of coal. Ferric iron-acid leach systems have been shown to be quite effective at removal of inorganic sulfur in coal. In this study, the oxidative effect of ferric iron in acid-leach systems was studied using dibenzothiophene, diphenyl sulfide, and di-n-butyl sulfide as models of organic sulfur groups in coal. Nitrogen and oxygen, as well as various transition metal catalysts and oxidants, were utilized in this investigation. Dibenzothiophene was found to be quite refractory to oxidation, except in the case where metavanadate was added, where it appears that 40% oxidation to sulfone could have occurred per hour at 150/sup 0/C and mild oxygen pressure. Diphenyl sulfide was selectively oxidized to sulfoxide and sulfone in an iron and oxygen system. Approximately 15% conversion to sulfone occurred per hour under these conditions. Some of the di-n-butyl sulfide was cracked to 1-butene and 1-butanethiol under similar conditions. Zinc chloride and ferric iron were used at 200/sup 0/C in an attempt to desulfonate dibenzothiophene sulfone, diphenyl sulfone, and di-n-butyl sulfone. Di-n-butyl sulfone was completely desulfurized on one hour and fragmented to oxidized parafins, while dibenzothiophene sulfone and diphenyl sulfone were unaffected. These results suggest that an iron-acid leach process could only selectively oxidize aryl sulfides under mild conditions, representing only 20% of the organic sulfur in coal (8% of the total sulfur). Removal through desulfonation once selective sulfur oxidation had occurred was only demonstrated for alkyl sulfones, with severe oxidation of the fragmented paraffins also occurring in one hour.
Calixarene crown ether solvent composition and use thereof for extraction of cesium from alkaline waste solutions
Moyer, Bruce A. (Oak Ridge, TN); Sachleben, Richard A. (Knoxville, TN); Bonnesen, Peter V. (Knoxville, TN); Presley, Derek J. (Ooltewah, TN)
A solvent composition and corresponding method for extracting cesium (Cs) from aqueous neutral and alkaline solutions containing Cs and perhaps other competing metal ions is described. The method entails contacting an aqueous Cs-containing solution with a solvent consisting of a specific class of lipophilic calix[4]arene-crown ether extractants dissolved in a hydrocarbon-based diluent containing a specific class of alkyl-aromatic ether alcohols as modifiers. The cesium values are subsequently recovered from the extractant, and the solvent subsequently recycled, by contacting the Cs-containing organic solution with an aqueous stripping solution. This combined extraction and stripping method is especially useful as a process for removal of the radionuclide cesium-137 from highly alkaline waste solutions which are also very concentrated in sodium and potassium. No pre-treatment of the waste solution is necessary, and the cesium can be recovered using a safe and inexpensive stripping process using water, dilute (millimolar) acid solutions, or dilute (millimolar) salt solutions. An important application for this invention would be treatment of alkaline nuclear tank wastes. Alternatively, the invention could be applied to decontamination of acidic reprocessing wastes containing cesium-137.
Identification of volatile butyl rubber thermal-oxidative degradation products by cryofocusing gas chromatography/mass spectrometry (cryo-GC/MS).
Smith, Jonell Nicole; White, Michael Irvin; Bernstein, Robert; Hochrein, James Michael
Chemical structure and physical properties of materials, such as polymers, can be altered as aging progresses, which may result in a material that is ineffective for its envisioned intent. Butyl rubber formulations, starting material, and additives were aged under thermal-oxidative conditions for up to 413 total days at up to 124 %C2%B0C. Samples included: two formulations developed at Kansas City Plant (KCP) (%236 and %2310), one commercially available formulation (%2321), Laxness bromobutyl 2030 starting material, and two additives (polyethylene AC-617 and Vanax MBM). The low-molecular weight volatile thermal-oxidative degradation products that collected in the headspace over the samples were preconcentrated, separated, and detected using cryofocusing gas chromatography mass spectrometry (cryo-GC/MS). The majority of identified degradation species were alkanes, alkenes, alcohols, ketones, and aldehydes. Observations for Butyl %2310 aged in an oxygen-18 enriched atmosphere (18O2) were used to verify when the source of oxygen in the applicable degradation products was from the gaseous environment rather than the polymeric mixture. For comparison purposes, Butyl %2310 was also aged under non-oxidative thermal conditions using an argon atmosphere.
Molecular Dynamics Simulations of Tri-n-butyl-phosphate/n-Dodecane Mixture: Thermophysical Properties and Molecular Structure
de Almeida, Valmor F [ORNL; Cui, Shengting [ORNL; Khomami, Bamin [ORNL
Molecular dynamics simulations of tri-n-butyl-phosphate (TBP)/n-dodecane mixture in the liquid phase have been carried out using two recently developed TBP force field models (J. Phys. Chem. B 2012, 116, 305) in combination with the all-atom optimized potentials for liquid simulations (OPLS-AA) force field model for n-dodecane. Specifically, the electric dipole moment of TBP, mass density of the mixture, and the excess volume of mixing were computed with TBP mole fraction ranging from 0 to 1. It is found that the aforementioned force field models accurately predict the mass density of the mixture in the entire mole fraction range. Commensurate with experimental measurements, the electric dipole moment of the TBP was found to slightly increase with the mole fraction of TBP in the mixture. Also, in accord with experimental data, the excess volume of mixing is positive in the entire mole fraction range, peaking at TBP mole fraction range 0.3 0.5. Finally, a close examination of the spatial pair correlation functions between TBP molecules, and between TBP and n-dodecane molecules, revealed formation of TBP dimers through self-association at close distance, a phenomenon with ample experimental evidence.
Propylene glycol monomethyl ether. A 3-generation study of isomer effects on reproductive and developmental parameters in rats.
Boyer, Edmond
1 Propylene glycol monomethyl ether. A 3-generation study of isomer effects on reproductive tel +33 (0) 3 44 55 62 64, fax +33 (0)3 44 55 66 05, E- mail : email@example.com Propylene reproductive toxicity E Lemazurier et al. ineris-00961896,version1-20Mar2014 #12;3 Introduction Propylene
Title: Decomposition of ethanol and dimethyl-ether during CVD synthesis of single-walled carbon nanotubes
Maruyama, Shigeo
of ethanol and dimethyl-ether during CVD synthesis of single-walled carbon nanotubes Author list: Bo Hou (single-walled carbon nanotubes) was investigated. Gas-phase thermal decomposition of ethanol and DME ethanol and DME decomposition, confirming expected reaction trends and primary byproducts. Peak
Effects of oxygenate concentration on species mole fractions in premixed n-heptane flames
Senkan, Selim M.
-heptane/oxygenate mixtures were 2.7 and 3.4. Three different fuel oxygenates (i.e. MTBE, methanol, and ethanol) were tested tertiary-butyl ether (MTBE), ethyl tertiary-butyl ether (ETBE), and tertiary amyl methyl ether (TAME)) were considered as possible fuel oxygenates. MTBE and ethanol are the most common oxygenates currently used
Use of aluminum phosphate as the dehydration catalyst in single step dimethyl ether process
Peng, Xiang-Dong (Allentown, PA); Parris, Gene E. (Coopersburg, PA); Toseland, Bernard A. (Allentown, PA); Battavio, Paula J. (Allentown, PA)
The present invention pertains to a process for the coproduction of methanol and dimethyl ether (DME) directly from a synthesis gas in a single step (hereafter, the "single step DME process"). In this process, the synthesis gas comprising hydrogen and carbon oxides is contacted with a dual catalyst system comprising a physical mixture of a methanol synthesis catalyst and a methanol dehydration catalyst. The present invention is an improvement to this process for providing an active and stable catalyst system. The improvement comprises the use of an aluminum phosphate based catalyst as the methanol dehydration catalyst. Due to its moderate acidity, such a catalyst avoids the coke formation and catalyst interaction problems associated with the conventional dual catalyst systems taught for the single step DME process.
Technical and operational overview of the C[sub 4] Oleflex process at Valero refinery
Hohnholt, J.F.; Payne, D. (Valero Refining Co., Corpus Christi, TX (United States)); Gregor, J.; Smith, E. (UOP, Des Plaines, IL (United States))
Changes in gasoline composition stemming from the 1990 Clean Air Act (CAA) Amendments prompted Valero Energy Corporation to evaluate options for producing reformulated gasoline. The evaluation culminated in a project to upgrade butanes into methyl tertiary butyl ether (MTBE). Technology selection focused on the dehydrogenation of isobutane, and the UOP Oleflex process was selected. The MTBE project was implemented in 34 months and was $3 million under budget. The guaranteed MTBE production of 12,500 BPSD was achieved within one month of mechanical completion and has since reached 15,000 BPSD. Even at the low MTBE prices prevailing in late 1993, the butane upgrading project contributed significantly to Valero Refinery's overall profitability. Worldwide demand is expected to increase MTBE prices in 1996, thereby further increasing profits. The paper describes the project evaluation activities which led to the selection of the Oleflex process, engineering and construction, the MTBE complex start-up and operation, the Valero MTBE complex performance, and future plans. The paper also discusses feedstock utilization efficiency and MTBE market analysis.
Carbon-carbon bond cleavage of 1,2-hydroxy ethers b7 vanadium(V) dipicolinate complexes
Hanson, Susan K [Los Alamos National Laboratory; Gordon, John C [Los Alamos National Laboratory; Thorn, David L [Los Alamos National Laboratory; Scott, Brian L [Los Alamos National Laboratory; Baker, R Tom [Los Alamos National Laboratory
The development of alternatives to current petroleum-based fuels and chemicals is becoming increasingly important due to concerns over climate change, growing world energy demand, and energy security issues. Using non-food derived biomass to produce renewable feedstocks for chemicals and fuels is a particularly attractive possibility. However, the majority of biomass is in the form of lignocellulose, which is often not fully utilized due to difficulties associated with breaking down both lignin and cellulose. Recently, a number of methods have been reported to transform cellulose directly into more valuable materials such as glucose, sorbitol, 5-(chloromethyl)furfural, and ethylene glycol. Less progress has been made with selective transformations of lignin, which is typically treated in paper and forest industries by kraft pulping (sodium hydroxide/sodium sulfide) or incineration. Our group has begun investigating aerobic oxidative C-C bond cleavage catalyzed by dipicolinate vanadium complexes, with the idea that a selective C-C cleavage reaction of this type could be used to produce valuable chemicals or intermediates from cellulose or lignin. Lignin is a randomized polymer containing methoxylated phenoxy propanol units. A number of different linkages occur naturally; one of the most prevalent is the {beta}-O-4 linkage shown in Figure 1, containing a C-C bond with 1,2-hydroxy ether substituents. While the oxidative C-C bond cleavage of 1,2-diols has been reported for a number of metals, including vanadium, iron, manganese, ruthenium, and polyoxometalate complexes, C-C bond cleavage of 1,2-hydroxy ethers is much less common. We report herein vanadium-mediated cleavage of C-C bonds between alcohol and ether functionalities in several lignin model complexes. In order to explore the scope and potential of vanadium complexes to effect oxidative C-C bond cleavage in 1,2-hydroxy ethers, we examined the reactivity of the lignin model complexes pinacol monomethyl ether (A), 2-phenoxyethanol (B), and 1,2-diphenyl-2-methoxyethanol (C) (Figure 1). Reaction of (dipic)V{sup V}(O)O{sup i}Pr (1a) or (dipic)V{sup v}(O)OEt (lb) with A, B, or C in acetonitrile yielded new vanadium(V) complexes where the alcohol-ether ligand was bound in a chelating fashion. From the reaction of 1b with pinacol monomethyl ether (A) in acetonitrile solution, (dipic)V{sup v}(O)(pinOMe) (2) (PinOMe = 2,3-dimethyl-3-methoxy-2-butanoxide) was isolated in 61 % yield. Reaction of 1b with 2-phenoxyethanol (B) in acetonitrile gave the new complex (dipic)V{sup v}(O)(OPE) (3) (OPE = 2-phenoxyethoxide), which was isolated in 76% yield. In a similar fashion, 1a reacted with 1,2-diphenyl-2-methoxyethanol (C) to give (dipic)V(O)(DPME) (4) (DPME = 1,2-diphenyl-2-methoxyethoxide), which was isolated in 39% yield. Complexes 2, 3, and 4 were characterized by {sup 1}H NMR and IR spectroscopy, elemental analysis, and X-ray crystallography. Compared to the previously reported vanadium(V) pinacolate complex (dipic)V(O)(pinOH) the X-ray structure of complex 2 reveals a slightly shorter V = O bond, 1.573(2) {angstrom} vs 1.588(2) {angstrom} for the pinOH structure. Complexes 3 and 4 display similar vanadium oxo bond distances of 1.568(2) {angstrom} and 1.576(2) {angstrom}, respectively. All three complexes show longer bonds to the ether-oxygen trans to the oxo (2.388(2) {angstrom} for 2, 2.547(2) {angstrom} for 3, and 2.438(2) {angstrom} for 4) than to the hydroxy-oxygen in the pinOH structure (2.252(2) {angstrom}).
Advanced emission-speciation methodologies for the Auto/Oil Air Quality Improvement Research Program. 1. Hydrocarbons and ethers
Jensen, T.E.; Siegl, W.O.; Lipari, F.; Loo, J.F.; Sigsby, J.E.
An analytical method for the determination of hydrocarbon and ether emissions from gasoline-, methanol-, and flexible-fueled vehicles is described. This method was used in Phase I of the Auto/Oil Air Quality Improvement Research Program to provide emissions data for various vehicles using individual reformulated gasolines and alternate fuels. These data would then be used for air modeling studies. Emission samples for tailpipe, evaporative, and running loss were collected in Tedlar bags. Gas chromatographic analysis of the emissions samples included 140 components (hydrocarbons, ethers, alcohols and aldehydes) between C1 and C12 in a single analysis of 54-minutes duration. Standardization, quality control procedures, and inter-laboratory comparisons developed and completed as part of this program are also described. (Copyright (c) 1992 Society of Automotive Engineers, Inc.).
Polybrominated diphenyl ethers (PBDEs) in leachates from selected landfill sites in South Africa
Odusanya, David O. [Department of Environmental, Water and Earth Sciences, Faculty of Science, Tshwane University of Technology, Private Bag X680, 175 Nelson Mandela Drive, Arcadia, Pretoria 0001 (South Africa); Okonkwo, Jonathan O. [Department of Environmental, Water and Earth Sciences, Faculty of Science, Tshwane University of Technology, Private Bag X680, 175 Nelson Mandela Drive, Arcadia, Pretoria 0001 (South Africa)], E-mail: email@example.com; Botha, Ben [Department of Environmental, Water and Earth Sciences, Faculty of Science, Tshwane University of Technology, Private Bag X680, 175 Nelson Mandela Drive, Arcadia, Pretoria 0001 (South Africa)
The last few decades have seen dramatic growth in the scale of production and the use of polybrominated diphenyl ethers (PBDEs) as flame retardants. Consequently, PBDEs such as BDE -28, -47, -66, -71, -75, -77, -85, -99, -100, -119, -138, -153, -154, and -183 have been detected in various environmental matrices. Generally, in South Africa, once the products containing these chemicals have outlived their usefulness, they are discarded into landfill sites. Consequently, the levels of PBDEs in leachates from landfill sites may give an indication of the general exposure and use of these compounds. The present study was aimed at determining the occurrence and concentrations of most common PBDEs in leachates from selected landfill sites. The extraction capacities of the solvents were also tested. Spiked landfill leachate samples were used for the recovery tests. Separation and determination of the PBDE congeners were carried out with a gas chromatograph equipped with Ni{sup 63} electron capture detector. The mean percentage recoveries ranged from 63% to 108% (n = 3) for landfill leachate samples with petroleum ether giving the highest percentage extraction. The mean concentrations of PBDEs obtained ranged from ND to 2670 pg l{sup -1}, ND to 6638 pg l{sup -1}, ND to 7230 pg l{sup -1}, 41 to 4009 pg l{sup -1}, 90 to 9793 pg l{sup -1} for the Garankuwa, Hatherly, Kwaggarsrand, Soshanguve and Temba landfill sites, respectively. Also BDE -28, -47, -71 and BDE-77 were detected in the leachate samples from all the landfill sites; and all the congeners were detected in two of the oldest landfill sites. The peak concentrations were recorded for BDE-47 at three sites and BDE-71 and BDE-75 at two sites. The highest concentration, 9793 {+-} 1.5 pg l{sup -1}, was obtained for the Temba landfill site with the highest BOD value. This may suggest some influence of organics on the level of PBDEs. Considering the leaching characteristics of brominated flame retardants, there is a high possibility that with time these compounds may infiltrate into the groundwater around the sites since most of the sites are not adequately lined.
Isobaric vapor-liquid equilibria in the systems methyl 1,1-dimethylethyl ether + hexane and + heptane
Wisniak, J.; Magen, E.; Shachar, M.; Zeroni, I.; Segura, H. [Ben-Gurion Univ. of the Negev, Beer-Sheva (Israel). Dept. of Chemical Engineering] [Ben-Gurion Univ. of the Negev, Beer-Sheva (Israel). Dept. of Chemical Engineering; Reich, R. [Univ. de Concepcion (Chile). Dept. of Chemical Engineering] [Univ. de Concepcion (Chile). Dept. of Chemical Engineering
The vapor-liquid equilibrium at 94 kPa has been determined for the binary systems of methyl 1,1-dimethylethyl ether (MTBE) with hexane and with heptane. Both systems deviate slightly from ideal behavior, can be described as regular solutions, and do not present an azeotrope. The activity coefficients and boiling point of the solutions were correlated with its composition by the Redlich-Kister, Wohl, Wilson, UNIQUAC, NRTL, and Wisniak-Tamir equations.
Derivation of a human equivalent concentration for n-butanol using a physiologically based pharmacokinetic model for n-butyl acetate and metabolites n-butanol and n-butyric acid
Teeguarden, Justin G.; Deisinger, P. J.; Poet, Torka S.; English, J C.; Faber, W D.; Barton, H. A.; Corley, Rick A.; Clewell, III, H. J.
The metabolic series (family) approach for risk assessment uses a dosimetry-based analysis to develop toxicity information for a group of metabolically linked compounds using pharmacokinetic (PK) data for each compound and toxicity data for the parent compound. An initial physiologically-based pharmacokinetic (PBPK) model was developed to support the implementation of the metabolic series approach for n-butyl acetate and its subsequent metabolites, n-butanol, and n-butyric acid (the butyl series) (Barton et al. 2000). In conjunction with pilot pharmacokinetic studies, the model was used to design the definitive intravenous (i.v.) PK studies. Rats were implanted with dual indwelling cannulae and administered test compounds by i.v. bolus dose, i.v. infusion, or by inhalation in a recirculating closed chamber. Hepatic, vascular and extravascular metabolic constants for metabolism were estimated by fitting the model to the blood time course data from these experiments. The respiratory bioavailability of n-butyl acetate and n-butanol was estimated from closed chamber inhalation studies and measured ventilation rates. The resulting butyl series PBPK model successfully reproduces the blood time course of these compounds following i.v. administration, and inhalation exposure to n-butyl acetate and n-butanol. A fully scaled human version of the model successfully reproduces arterial blood n-butanol kinetics following inhalation exposure to n-butanol. These validated i.v (rat) and inhalation route models (rat, butyl acetate, n-butanol; human, butanol only) can be used to support species and dose-route extrapolations required for risk assessment of butyl series family of compounds. Further, this work demonstrates the usefulness of i.v. kinetic data for parameterization of systemic metabolism and the value of collaboration between experimentalists and kineticists in the development of PBPK models. The product of this effort, validated rat and human PBPK models for the butyl series compounds, illustrates the effectiveness of broad multi-institutional public/private collaborations in the pursuit of developing state of the art tools for risk assessment.
A fluorescence-based method for rapid and direct determination of Polybrominated Diphenyl Ethers in Water
Shan, Huimei; Liu, Chongxuan; Wang, Zheming; Ma, Teng; Shang, Jianying; Pan, Duoqiang
A new method was developed for rapid and direct measurement of aqueous polybrominated diphenyl ethers (PBDEs) using fluorescence spectroscopy. The fluorescence spectra of aqueous tri- to deca-BDE (BDE28, 47, 99, 153, 190 and 209) that are commonly found in environment were determined at variable emission and excitation wavelengths. The results revealed that the PBDEs have distinct fluorescence spectral profiles and peak positions that can be exploited to identify these species and determine their concentrations in aqueous solutions. The detection limits as determined in deionized water spiked with PBDEs are 1.71-5.82 ng/L for BDE28, BDE47, BDE190 and BDE209, and 45.55-69.95 ng/L for BDE99 and BDE153. The effects of environmental variables including pH, humic substance, and groundwater chemical composition on PBDEs measurements were also investigated. These environmental variables affected fluorescence intensity, but their effect can be corrected through linear additivity and separation of spectral signal contribution. Compared with conventional GC-based analytical methods, the fluorescence spectroscopy method is more efficient as it only uses a small amount of samples (4 ml), avoids lengthy complicated concentration and extraction steps, and has a low detection limit of a few ng/L.
Thermophysical properties of 2,2,2-trifluoroethanol + tetraethylene glycol dimethyl ether
Herraiz, J.; Olive, F.; Zhu, S.; Shen, S.; Coronas, A. [Univ. Rovira i Virgili, Tarragona (Spain). Dept. of Mechanical Engineering] [Univ. Rovira i Virgili, Tarragona (Spain). Dept. of Mechanical Engineering
Isothermal P,x data from 303.15 K to 423.15 K, liquid densities from 283.15 K to 423.15 K, and dynamic viscosities from 343.15 K to 393.15 K for the binary system 2,2,2-trifluoroethanol + tetraethylene glycol dimethyl ether were measured. The vapor-liquid equilibrium (VLE) data were measured. The vapor-liquid equilibrium (VLE) data were measured using a static apparatus. VLE data were correlated by the five-parameter NRTL equation, while density and kinematic viscosity data were correlated with temperature and liquid composition using empirical equations. The viscosity data used in the correlation cover the range of 293.15--393.15 K. VLE data indicate that this binary system exhibits large negative deviations from Raoult`s law. These mixtures present large exothermic excess molar enthalpies. The excess molar enthalpy calculated using the Gibbs-Helmholtz equation and the NRTL parameters was compared with experimental data existing in the literature.
Multiple Objective Stormwater Management For the Coliseum Complex
Jones, Jesse; Kraai, Rachel
methyl tertiary butyl ether (MTBE) remain in the soil around5.2 ppb xylenes, and 160 ppb MTBE remain in the groundwater
aromatic compound mixtures: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
and mineralization potentials of gasoline monoaromatics and methyl tert-butyl ether (MTBE), compounds that commonly co-exist in groundwater contaminant plumes. A mixed culture...
Stratospheric ozone, global warming, and the principle of unintended consequences - an ongoing science and policy story
as methyl-tert-butyl ether (MTBE), lubricating oil and itsthe environment. Use of the MTBE additive in gasoline wasof gasoline laced with MTBE into groundwater resulted in
The Drinking Water Security and Safety Amendments of 2002: Is America's Drinking Water Infrastructure Safer Four Years Later?
Shermer, Steven D.
355 tertiary butyl ether ("MTBE"). 43 8 Amazingly, even "[c]Water: Study Estimates Cost of MTBE Remedia- tion At Up to $
Agricultural and Resource Economics Update
Smith, Aaron; Zilberman, David; Saitone, Tina; Sexton, Richard J.
tertiary butyl ether (MTBE), a natural-gas derivative, werebattle between advocates for ethanol and those for MTBE.MTBE became the dominant additive because it was less
Biomass burning and urban air pollution over the Central Mexican Plateau
the urban tracers (e.g. C 2 H 2 , MTBE, toluene) are highlymethyl tert-butyl ether (MTBE) because their shorter atmo-
Effects of water chemistry on NF/RO membrane structure and performance
Mo, Yibing
methyl tert-butyl ether (MTBE), benzene, ethylbenzene,TCE** Industrial C 2 HCl 3 MTBE** [48] Industrial C 5 H 12 O
Hazen, Terry C.
Intrinsic bioremediation of MTBE-contaminated groundwater atcontaminants, e.g. PCE, TCE, MTBE, TNT, dioxane, atrazine,Methyl tert-butyl ether (MTBE) has also been remediated
First Annual U.S. Department of Energy Office of Science Joint Genome Institute User Meeting
Genome Analysis of MTBE-Degrading Beta- Proteobacteriummethyl tert- butyl ether (MTBE). Strain PM1 can alsooften co-contaminants with MTBE in groundwater, including
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
which can lead to public health problems. * MtBE (Methyl tert Butyl Ether), a gasoline additive, has begun to contaminate ground water supplies. * Similarly, perchlorate has...
This journal is c the Owner Societies 2012 Phys. Chem. Chem. Phys., 2012, 14, 675680 675 Cite this: Phys. Chem. Chem. Phys., 2012, 14, 675680
Neumark, Daniel M.
-octane and in the oxidation of fuel additives such as MTBE and ETBE (methyl and ethyl t-butyl ether).1 The chemistry
Pyrolysis of Organic Molecules Relevant to Combustion as Monitored by Photoionization Time-of-Flight Mass Spectrometry
Weber, Kevin Howard
is observed, which is similar to MTBE in this system whichisobutene formed from MTBE, is found to occur. REFERENCES [methyl tert-butyl ether (MTBE) and tert-amyl methyl ether (
() Trichloromethane ()1,1,2,2-1,1,2,2-Tetrachloroethane
Huang, Haimei
acetate () Ethylene glycol monobutyl ether () Ethylene glycol monomethy ether ()- O-dichlorobenzene ( ) Xylenes(o-,m-,p- isomers) () Cresol - 19 - #12;() Chlorobenzene () Amyl acetate () Isoamyl acetate () Isobutyl acetate () Isopropyl acetate () Ethyl acetate () Propyl acetate () Butyl acetate () Methyl acetate
Structural Properties of Tetra-tert-butyl Zinc(II) Phthalocyanine Isomers on a Au(111) Z. T. Deng, H. M. Guo, W. Guo, L. Gao, Z. H. Cheng, D. X. Shi, and H.-J. Gao*
Gao, Hongjun
. Deng, H. M. Guo, W. Guo, L. Gao, Z. H. Cheng, D. X. Shi, and H.-J. Gao* Beijing National LaboratoryStructural Properties of Tetra-tert-butyl Zinc(II) Phthalocyanine Isomers on a Au(111) Surface Z. T
Mechanistic Investigation of Acid-Catalyzed Cleavage of Aryl-Ether Linkages: Implications for Lignin Depolymerization
Sturgeon, M. R.; Kim, S.; Chmely, S. C.; Foust, T. D.; Beckham, G. T.
Carbon-oxygen bonds are the primary inter-monomer linkages lignin polymers in plant cell walls, and as such, catalyst development to cleave these linkages is of paramount importance to deconstruct biomass to its constituent monomers for the production of renewable fuels and chemicals. For many decades, acid catalysis has been used to depolymerize lignin. Lignin is a primary component of plant cell walls, which is connected primarily by aryl-ether linkages, and the mechanism of its deconstruction by acid is not well understood, likely due to its heterogeneous and complex nature compared to cellulose. For effective biomass conversion strategies, utilization of lignin is of significant relevance and as such understanding the mechanisms of catalytic lignin deconstruction to constituent monomers and oligomers is of keen interest. Here, we present a comprehensive experimental and theoretical study of the acid catalysis of a range of dimeric species exhibiting the b-O-4 linkage, the most common inter-monomer linkage in lignin. We demonstrate that the presence of a phenolic species dramatically increases the rate of cleavage in acid at 150 degrees C. Quantum mechanical calculations on dimers with the para-hydroxyl group demonstrate that this acid-catalyzed pathway differs from the nonphenolic dimmers. Importantly, this result implies that depolymerization of native lignin in the plant cell wall will proceed via an unzipping mechanism wherein b-O-4 linkages will be cleaved from the ends of the branched, polymer chains inwards toward the center of the polymer. To test this hypothesis further, we synthesized a homopolymer of b-O-4 with a phenolic hydroxyl group, and demonstrate that it is cleaved in acid from the end containing the phenolic hydroxyl group. This result suggests that genetic modifications to lignin biosynthesis pathways in plants that will enable lower severity processes to fractionate lignin for upgrading and for easier access to the carbohydrate fraction of the plant cell wall.
Thermally Switchable Thin Films of an ABC Triblock Copolymer of Poly(n-butyl methacrylate)-poly(methyl methacrylate)-poly(2-fluoroethyl methacrylate)
Zhang, Shanju [Georgia Institute of Technology; Liu, Zhan [Georgia Institute of Technology; Bucknall, David G. [Georgia Institute of Technology; He, Lihong [ORNL; Hong, Kunlun [ORNL; Mays, Jimmy [ORNL; Allen, Mark [Georgia Institute of Technology
The thermo-responsive behavior of polymer films consisting of novel linear triblock copolymers of poly(n-butyl methacrylate)-poly(methyl methacrylate)-poly(2-fluoroethyl methacrylate) (PnBuMA-PMMA-P2FEMA) are reported using differential scanning calorimetry (DSC), atomic forcing microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and contacting angle (CA) measurements. The surface morphology, wettability and chemical structure of thin films of these triblock copolymers on silicon wafers as a function of temperature have been investigated. It has been shown that the wettability of the films is thermally switchable. Detailed structural analysis shows that thermo-responsive surface composition changes are produced. The underlying mechanism of the thermoresponsive behavior is discussed.
MTBE still in poor health, despite the Clean Air Act
Wood, A.
After the second winter oxygenated fuels program of the 1990 Clean Air Act, producers of methyl tert-butyl ether (MTBE) are still feeling the chill of poor profitability. Despite the strong demand growth for MTBE to meet oxygen requirements in reformulated gasoline (RFG), oversupply still dogs the market. That, combined with a run-up in feedstock prices, has seen margins for MTBE markers all but evaporate. And it seems matters are likely to get worse before they get better. This week, Belvieu Environmental Fuels (BEF; Houston) expects to startup its 15,000-bbl/day MTBE plant at Mont Belvieu, TX. In late July, Texaco will start up its 15,000-bbl/day MTBE/propylene oxide (PO) plant at Port Neches, TX. In addition, a rash of refinery-based MTBE and tert-amyl methyl ether projects are nearing completion. {open_quotes}Profitability in MTBE has been extremely poor,{close_quotes} says Marvin O. Schlanger, president of Arco Chemical Americas, the largest MTBE producer. There has, however, been some recent recovery on the spot market, with MTBE moving from less than 60 cts/gal to near cash-cost levels of 70 cts/gal. But contract prices remain depressed, and strength in butane and methanol pricing have all buy wiped out any gains in MTBE.
SYNTHESIS OF NOVEL CROWN ETHERS BEARING THE exo-cis-2,3-NORBORNYL GROUP AS POTENTIAL Na+ AND K+ EXTRACTANTS
Robeson, R.M.; Bonnesen, P.
The synthesis of a series of novel dinorbornyl-16-crown-5 and dinorbornyl-18-crown-6 ethers that incorporate the exo-cis-2,3-norbornyl moiety within the macrocycle framework is described. The key starting material for the crown ethers, exo-cis-2,3-norbornanediol, was successfully prepared on a large (>30g) scale in 88% yield from norbornylene by osmium tetroxide-catalyzed hydroxylation. The syn and anti isomers of the dinorbornyl-16-crown-5 ether family were prepared using diethylene glycol with ring closure achieved using a methallyl linkage. The isomers cis-syn-cis and cis-anti-cis di-norbornano-15-methyleno-16-crown-5 (6A and 6B) could be separated using column chromatography, and a single crystal of the syn isomer 6A suitable for X-ray crystal structure analysis was obtained, thereby confi rming the syn orientation. The syn and anti isomers of the dinorbornyl-18-crown-6 ether family were successfully prepared employing a different synthetic strategy, involving the potassium–templated cyclization of two bis-hydroxyethoxy-substituted exo-cis-2,3-norbornyl groups under high dilution conditions. Attempts to fully separate cis-syn-cis di-norbornano-18-crown-6 (10A) and cis-anti-cis di-norbornano-18-crown-6 (10B) from one another using column chromatography were unsuccessful. All intermediates and products were checked for purity using either thin layer chromatography or gas chromatography, and characterized by proton and carbon NMR. Crown ethers 6AB and 10AB are to our knowledge the fi rst crown ethers to incorporate the exo-cis-2,3-norbornyl moiety into the crown ring to be successfully synthesized and characterized.
(2R)-4-Oxo-4[3-(Trifluoromethyl)-5,6-diihydro:1,2,4}triazolo[4,3-a}pyrazin-7(8H)-y1]-1-(2,4,5-trifluorophenyl)butan-2-amine: A Potent, Orally Active Dipeptidyl Peptidase IV Inhibitor for the Treatment of Type 2 Diabetes
Kim, D.; Wang, L.; Beconi, M.; Eiermann, G.; Fisher, M.; He, H.; Hickey, G.; Kowalchick, Jennifer; Leiting, Barbara; Lyons, K.; Marsilio, F.; McCann, F.; Patel, R.; Petrov, A.; Scapin, G.; Patel, S.; Roy, R.; Wu, J.; Wyvratt, M.; Zhang, B.; Zhu, L.; Thornberry, N.; Weber, A. (Merck)
A novel series of {beta}-amino amides incorporating fused heterocycles, i.e., triazolopiperazines, were synthesized and evaluated as inhibitors of dipeptidyl peptidase IV (DPP-IV) for the treatment of type 2 diabetes. (2R)-4-Oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine (1) is a potent, orally active DPP-IV inhibitor (IC{sub 50} = 18 nM) with excellent selectivity over other proline-selective peptidases, oral bioavailability in preclinical species, and in vivo efficacy in animal models. MK-0431, the phosphate salt of compound 1, was selected for development as a potential new treatment for type 2 diabetes.
Monitoring synaptic protein dynamics with higher temporal, spatial, and molecular resolution
Butko, Margaret
Spectrometry mSOG MiniSOG MTBE Methyl tert-butyl ether mTORMethyl tert-butyl ether (MTBE, 1.4 mL) was then added for1,000 g, 5 min). The MTBE layer was collected into a 1.5-mL
Water Research 37 (2003) 37563766 Seasonal and daily variations in concentrations of methyl-
Toran, Laura
- tertiary-butyl ether (MTBE) at Cranberry Lake, New Jersey Laura Torana, *, Charles Lipkaa , Arthur Baehrb; accepted 24 March 2003 Abstract Methyl-tertiary-butyl ether (MTBE), an additive used to oxygenate gasoline of gasoline-powered watercraft. This paper documents and explains both seasonal and daily variations in MTBE
UNIVERSITY OF CALIFORNIA Santa Barbara
California at Santa Barbara, University of
, B. Dooher, and D. Rice, Analysis of dissolved benzene plumes and methyl tertiary butyl ether (MTBE, An evaluation of MTBE impacts to California groundwater resources, pp. 68 p., Lawrence Livermore National, Temporal Analysis of Methyl Tertiary Butyl Ether (MTBE) Plumes at California Leaking Underground Fuel tank
channel voltage sensor+ether--go-go K Optical detection of rate-determining ion-modulated conformational changes of the
Bezanilla, Francisco
channel voltage sensor+ether-ŕ-go-go K Optical detection of rate-determining ion electrophysiological and optical approach. We find that a fluorescent probe attached near S4 in the voltage sensor.pnas.org/misc/reprints.shtml To order reprints, see: Notes: #12;Optical detection of rate-determining ion-modulated conformational
Single-Step Syngas-to-Distillates (S2D) Synthesis via Methanol and Dimethyl Ether Intermediates: Final Report
Dagle, Robert A.; Lebarbier, Vanessa MC; Lizarazo Adarme, Jair A.; King, David L.; Zhu, Yunhua; Gray, Michel J.; Jones, Susanne B.; Biddy, Mary J.; Hallen, Richard T.; Wang, Yong; White, James F.; Holladay, Johnathan E.; Palo, Daniel R.
The objective of the work was to enhance price-competitive, synthesis gas (syngas)-based production of transportation fuels that are directly compatible with the existing vehicle fleet (i.e., vehicles fueled by gasoline, diesel, jet fuel, etc.). To accomplish this, modifications to the traditional methanol-to-gasoline (MTG) process were investigated. In this study, we investigated direct conversion of syngas to distillates using methanol and dimethyl ether intermediates. For this application, a Pd/ZnO/Al2O3 (PdZnAl) catalyst previously developed for methanol steam reforming was evaluated. The PdZnAl catalyst was shown to be far superior to a conventional copper-based methanol catalyst when operated at relatively high temperatures (i.e., >300°C), which is necessary for MTG-type applications. Catalytic performance was evaluated through parametric studies. Process conditions such as temperature, pressure, gas-hour-space velocity, and syngas feed ratio (i.e., hydrogen:carbon monoxide) were investigated. PdZnAl catalyst formulation also was optimized to maximize conversion and selectivity to methanol and dimethyl ether while suppressing methane formation. Thus, a PdZn/Al2O3 catalyst optimized for methanol and dimethyl ether formation was developed through combined catalytic material and process parameter exploration. However, even after compositional optimization, a significant amount of undesirable carbon dioxide was produced (formed via the water-gas-shift reaction), and some degree of methane formation could not be completely avoided. Pd/ZnO/Al2O3 used in combination with ZSM-5 was investigated for direct syngas-to-distillates conversion. High conversion was achieved as thermodynamic constraints are alleviated when methanol and dimethyl are intermediates for hydrocarbon formation. When methanol and/or dimethyl ether are products formed separately, equilibrium restrictions occur. Thermodynamic relaxation also enables the use of lower operating pressures than what would be allowed for methanol synthesis alone. Aromatic-rich hydrocarbon liquid (C5+), containing a significant amount of methylated benzenes, was produced under these conditions. However, selectivity control to liquid hydrocarbons was difficult to achieve. Carbon dioxide and methane formation was problematic. Furthermore, saturation of the olefinic intermediates formed in the zeolite, and necessary for gasoline production, occurred over PdZnAl. Thus, yield to desirable hydrocarbon liquid product was limited. Evaluation of other oxygenate-producing catalysts could possibly lead to future advances. Potential exists with discovery of other types of catalysts that suppress carbon dioxide and light hydrocarbon formation. Comparative techno-economics for a single-step syngas-to-distillates process and a more conventional MTG-type process were investigated. Results suggest operating and capital cost savings could only modestly be achieved, given future improvements to catalyst performance. Sensitivity analysis indicated that increased single-pass yield to hydrocarbon liquid is a primary need for this process to achieve cost competiveness.
Fluctuating micro-heterogeneity in water–tert-butyl alcohol mixtures and lambda-type divergence of the mean cluster size with phase transition-like multiple anomalies
Banerjee, Saikat; Furtado, Jonathan; Bagchi, Biman, E-mail: email@example.com [SSCU, Indian Institute of Science, Bangalore 560012 (India)] [SSCU, Indian Institute of Science, Bangalore 560012 (India)
Water–tert-butyl alcohol (TBA) binary mixture exhibits a large number of thermodynamic and dynamic anomalies. These anomalies are observed at surprisingly low TBA mole fraction, with x{sub TBA} ? 0.03–0.07. We demonstrate here that the origin of the anomalies lies in the local structural changes that occur due to self-aggregation of TBA molecules. We observe a percolation transition of the TBA molecules at x{sub TBA} ? 0.05. We note that "islands" of TBA clusters form even below this mole fraction, while a large spanning cluster emerges above that mole fraction. At this percolation threshold, we observe a lambda-type divergence in the fluctuation of the size of the largest TBA cluster, reminiscent of a critical point. Alongside, the structure of water is also perturbed, albeit weakly, by the aggregation of TBA molecules. There is a monotonic decrease in the tetrahedral order parameter of water, while the dipole moment correlation shows a weak nonlinearity. Interestingly, water molecules themselves exhibit a reverse percolation transition at higher TBA concentration, x{sub TBA} ? 0.45, where large spanning water clusters now break-up into small clusters. This is accompanied by significant divergence of the fluctuations in the size of largest water cluster. This second transition gives rise to another set of anomalies around. Both the percolation transitions can be regarded as manifestations of Janus effect at small molecular level.
Low-temperature CVD of iron, cobalt, and nickel nitride thin films from bis[di(tert-butyl)amido]metal(II) precursors and ammonia
Cloud, Andrew N.; Abelson, John R., E-mail: firstname.lastname@example.com [Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, 201 Materials Science and Engineering Building, 1304 W. Green St., Urbana, Illinois 61801 (United States); Davis, Luke M.; Girolami, Gregory S., E-mail: email@example.com [School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, Illinois 61801 (United States)
Thin films of late transition metal nitrides (where the metal is iron, cobalt, or nickel) are grown by low-pressure metalorganic chemical vapor deposition from bis[di(tert-butyl)amido]metal(II) precursors and ammonia. These metal nitrides are known to have useful mechanical and magnetic properties, but there are few thin film growth techniques to produce them based on a single precursor family. The authors report the deposition of metal nitride thin films below 300?°C from three recently synthesized M[N(t-Bu){sub 2}]{sub 2} precursors, where M?=?Fe, Co, and Ni, with growth onset as low as room temperature. Metal-rich phases are obtained with constant nitrogen content from growth onset to 200?°C over a range of feedstock partial pressures. Carbon contamination in the films is minimal for iron and cobalt nitride, but similar to the nitrogen concentration for nickel nitride. X-ray photoelectron spectroscopy indicates that the incorporated nitrogen is present as metal nitride, even for films grown at the reaction onset temperature. Deposition rates of up to 18?nm/min are observed. The film morphologies, growth rates, and compositions are consistent with a gas-phase transamination reaction that produces precursor species with high sticking coefficients and low surface mobilities.
Enol Ethers as Substrates for Efficient Z- and Enantioselective Ring-Opening/Cross-Metathesis Reactions Promoted by Stereogenic-at-Mo Complexes: Utility in Chemical Synthesis and Mechanistic Attributes
Yu, Miao
The first examples of catalytic enantioselective ring-opening/cross-metathesis (EROCM) reactions that involve enol ethers are reported. Specifically, we demonstrate that catalytic EROCM of several oxa- and azabicycles, ...
Is Embolization of the Pancreas Safe? Pancreatic Histological Changes after Selective Transcatheter Arterial Embolization with N-Butyl Cyanoacrylate in a Swine Model
Okada, Takuya, E-mail: email@example.com; Yamaguchi, Masato [Kobe University Graduate School of Medicine, Department of Radiology (Japan); Takahashi, Takuya [Kobe Red Cross Hospital, Department of Pathology (Japan); Izaki, Kenta; Uotani, Kensuke; Sakamoto, Noriaki; Sugimura, Kazuro; Sugimoto, Koji [Kobe University Graduate School of Medicine, Department of Radiology (Japan)
Purpose: This study was designed to evaluate the safety of selective transcatheter arterial embolization (TAE) with N-butyl cyanoacrylate (NBCA) in a swine model in terms of histological changes in the pancreas. Methods: Three groups of two female swine (58-64 kg) per group underwent TAE of the dorsal pancreatic artery, under anesthesia, with 1:1, 1:4, and 1:9 mixtures of NBCA and iodized oil. Blood parameters were evaluated at days 1, 4, and 10 after TAE, after which the animals were sacrificed and pancreatic tissues were examined under light microscopy. Results: All of the animals were asymptomatic and survived for 10 days. Cone beam computed tomographic angiography revealed occlusion of the dorsal pancreatic artery and no enhancement in the embolized area. The white blood cell count and C-reactive protein level were elevated slightly on day 1 after TAE (mean {+-} SD: 252.7 {+-} 27.8 Multiplication-Sign 10{sup 2}/{mu}l and 0.15 {+-} 0.07 mg/l, respectively), but they normalized or remained near the upper normal limit thereafter. The serum amylase and lipase levels also were elevated on day 1 (8831.7 {+-} 2169.2 U/l and 130 {+-} 53.4 U/l, respectively) but normalized thereafter. Histologically, necrosis and fibrosis were noted only in the embolized segment, and necrosis and acute inflammatory reactions were absent in the nonembolized segment. The border between both segments was well defined. Lymphocytic infiltration and foreign body reaction were noted around the embolized vessels. Conclusions: Selective TAE with NBCA in the pancreas caused localized ischemic necrosis without clinically significant pancreatitis; therefore, this procedure is tolerable in swine.
Involvement of reactive oxygen species in brominated diphenyl ether-47-induced inflammatory cytokine release from human extravillous trophoblasts in vitro
Park, Hae-Ryung, E-mail: firstname.lastname@example.com; Kamau, Patricia W.; Loch-Caruso, Rita
Polybrominated diphenyl ethers (PBDEs) are widely used flame retardant compounds. Brominated diphenyl ether (BDE)-47 is one of the most prevalent PBDE congeners found in human breast milk, serum and placenta. Despite the presence of PBDEs in human placenta, effects of PBDEs on placental cell function are poorly understood. The present study investigated BDE-47-induced reactive oxygen species (ROS) formation and its role in BDE-47-stimulated proinflammatory cytokine release in a first trimester human extravillous trophoblast cell line, HTR-8/SVneo. Exposure of HTR-8/SVneo cells for 4 h to 20 ?M BDE-47 increased ROS generation 1.7 fold as measured by the dichlorofluorescein (DCF) assay. Likewise, superoxide anion production increased approximately 5 fold at 10 and 15 ?M and 9 fold at 20 ?M BDE-47 with a 1-h exposure, as measured by cytochrome c reduction. BDE-47 (10, 15 and 20 ?M) decreased the mitochondrial membrane potential by 47–64.5% at 4, 8 and 24 h as assessed with the fluorescent probe Rh123. Treatment with 15 and 20 ?M BDE-47 stimulated cellular release and mRNA expression of IL-6 and IL-8 after 12 and 24-h exposures: the greatest increases were a 35-fold increased mRNA expression at 12 h and a 12-fold increased protein concentration at 24 h for IL-6. Antioxidant treatments (deferoxamine mesylate, (±)?-tocopherol, or tempol) suppressed BDE-47-stimulated IL-6 release by 54.1%, 56.3% and 37.7%, respectively, implicating a role for ROS in the regulation of inflammatory pathways in HTR-8/SVneo cells. Solvent (DMSO) controls exhibited statistically significantly decreased responses compared with non-treated controls for IL-6 release and IL-8 mRNA expression, but these responses were not consistent across experiments and times. Nonetheless, it is possible that DMSO (used to dissolve BDE-47) may have attenuated the stimulatory actions of BDE-47 on cytokine responses. Because abnormal activation of proinflammatory responses can disrupt trophoblast functions necessary for placental development and successful pregnancy, further investigation is warranted of the impact of ROS and BDE-47 on trophoblast cytokine responses. - Highlights: • BDE-47 induced ROS overproduction and mitochondrial dysfunction. • BDE-47 stimulated production of proinflammatory cytokines. • Antioxidant treatment reduced BDE-47-stimulated ROS generation and cytokine release.
Heat Capacity Uncertainty Calculation for the Eutectic Mixture of Biphenyl/Diphenyl Ether Used as Heat Transfer Fluid: Preprint
Gomez, J. C.; Glatzmaier, G. C.; Mehos, M.
The main objective of this study was to calculate the uncertainty at 95% confidence for the experimental values of heat capacity of the eutectic mixture of biphenyl/diphenyl ether (Therminol VP-1) determined from 300 to 370 degrees C. Twenty-five samples were evaluated using differential scanning calorimetry (DSC) to obtain the sample heat flow as a function of temperature. The ASTM E-1269-05 standard was used to determine the heat capacity using DSC evaluations. High-pressure crucibles were employed to contain the sample in the liquid state without vaporizing. Sample handling has a significant impact on the random uncertainty. It was determined that the fluid is difficult to handle, and a high variability of the data was produced. The heat capacity of Therminol VP-1 between 300 and 370 degrees C was measured to be equal to 0.0025T+0.8672 with an uncertainty of +/- 0.074 J/g.K (3.09%) at 95% confidence with T (temperature) in Kelvin.
Synergistic effect of mixing dimethyl ether with methane, ethane, propane, and ethylene fuels on polycyclic aromatic hydrocarbon and soot formation
Yoon, S.S. [Corporate Research and Development Division, Hyundai-Kia Motors, Gyeonggi-do 445-706 (Korea); Anh, D.H. [Korea Electric Power Research Institute, Daejeon 305-380 (Korea); Chung, S.H. [School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742 (Korea)
Characteristics of polycyclic aromatic hydrocarbon (PAH) and soot formation in counterflow diffusion flames of methane, ethane, propane, and ethylene fuels mixed with dimethyl ether (DME) have been investigated. Planar laser-induced incandescence and fluorescence techniques were employed to measure relative soot volume fractions and PAH concentrations, respectively. Results showed that even though DME is known to be a clean fuel in terms of soot formation, DME mixture with ethylene fuel increases PAH and soot formation significantly as compared to the pure ethylene case, while the mixture of DME with methane, ethane, and propane decreases PAH and soot formation. Numerical calculations adopting a detailed kinetics showed that DME can be decomposed to produce a relatively large number of methyl radicals in the low-temperature region where PAH forms and grows; thus the mixture of DME with ethylene increases CH{sub 3} radicals significantly in the PAH formation region. Considering that the increase in the concentration of O radicals is minimal in the PAH formation region with DME mixture, the enhancement of PAH and soot formation in the mixture flames of DME and ethylene can be explained based on the role of methyl radicals in PAH and soot formation. Methyl radicals can increase the concentration of propargyls, which could enhance incipient benzene ring formation through the propargyl recombination reaction and subsequent PAH growth. Thus, the result substantiates the importance of methyl radicals in PAH and soot formation, especially in the PAH formation region of diffusion flames. (author)
Investigation of HCCI Combustion of Diethyl Ether and Ethanol Mixtures Using Carbon 14 Tracing and Numerical Simulations
Mack, J H; Dibble, R W; Buchholz, B A; Flowers, D L
Despite the rapid combustion typically experienced in Homogeneous Charge Compression Ignition (HCCI), components in fuel mixtures do not ignite in unison or burn equally. In our experiments and modeling of blends of diethyl ether (DEE) and ethanol (EtOH), the DEE led combustion and proceeded further toward completion, as indicated by {sup 14}C isotope tracing. A numerical model of HCCI combustion of DEE and EtOH mixtures supports the isotopic findings. Although both approaches lacked information on incompletely combusted intermediates plentiful in HCCI emissions, the numerical model and {sup 14}C tracing data agreed within the limitations of the single zone model. Despite the fact that DEE is more reactive than EtOH in HCCI engines, they are sufficiently similar that we did not observe a large elongation of energy release or significant reduction in inlet temperature required for light-off, both desired effects for the combustion event. This finding suggests that, in general, HCCI combustion of fuel blends may have preferential combustion of some of the blend components.
Acute toxicity of smoke screen materials to aquatic organisms, white phosphorus-felt, red phosphorus-butyl rubber and SGF No. 2 fog oil. Final report
Poston, T.M.; McFadden, K.M.; Bean, R.M.; Clark, M.L.; Thomas, B.L.; Killand, B.W.; Prohammer, L.A.; Kalkwarf, D.R.
The acute toxicity of three obscurants was determined for nine freshwater organisms. The materials tested were white phosphorus-felt smoke, red phosphorus-butyl rubber (RP-BR) smoke, and smoke generator fuel (SGF) No. 2 fog oil (bulk and vaporized). The chemistry of WP-F and RP-BR smoke in water and the resulting effects on aquatic organisms are similar. Combustion of these two obscurants and their deposition in water leads to the formation of many complex oxy-phosphoric acids. Rates of hydrolysis of these complex products to ortho-phosphate were inconsistent and unpredictable over time. These products acidify water and produce toxic effects after exhausting the buffering capacity of the water. Acute 96 hr tests using Daphnia magna with neutralized and nonneutralized exposure solutions indicated that the presence of unidentified toxic component(s) acted independently of pH. At pH levels of 6.0 to 7.0, phosphorus combustion products precipitated out of solution leading to a bimodal toxic response in extended 96-hr tests with Daphnia magna. Most components of fog oil had low solubility in water. Saturation was apparent at approximately 0.1 to 0.3 mg/L total oil. Vaporization had no demonstrable effect on the chemistry or toxicity of the fog oil. Neither the bulk fog oil nor the vaporized fog oil was acutely toxic to freshwater animals at concentrations less than 10 mg/L total oil. In oil-water mixes in excess of 1.0 mg/L total oil, fog oil quickly separated and floated to the surface. The primary hazard associated with vaporized and bulk fog oil was the physical effect of oil fouling the organisms. Photolysis increased the concentration of water-soluble components of the fog oil. Acute toxicity was demonstrated in oil-water mixes (approx.10 mg/L total oil) of photolyzed bulk and vaporized fog oil. No difference in toxicity was observed between photolyzed and non-photolyzed dilutions of OWM at comparable levels of total oil.
Approaches to the synthesis of macrocyclic polystannanes
Denis, Richard Ascot
(trimethylstannyl) butane Preparation of 1, 4-bis(trimethylstannyl) butane using Trimethyltin Lithium. Preparation of 1, 5-bis(trimethylstannyl) pentane. Preparation of 1, 3-bis(Bromodimethylstannylj propane (39a) . Preparation of 1, 4-bis... investigated by pedersen who reported that the solubility of dibenzo-18-crown-6 in methanol was increased in the presence of alkali (lithium ion excluded) and alkaline earth salts. This was 14 the first report of a cation being complexed by crown ethers...
Synthesis of Methanol and Dimethyl Ether from Syngas over Pd/ZnO/Al2O3 Catalysts
Lebarbier, Vanessa MC; Dagle, Robert A.; Kovarik, Libor; Lizarazo Adarme, Jair A.; King, David L.; Palo, Daniel R.
A Pd/ZnO/Al2O3 catalyst was developed for the synthesis of methanol and dimethyl ether (DME) from syngas. Studied were temperatures of operation ranging from 250°C to 380°C. High temperatures (e.g. 380°C) are necessary when combining methanol and DME synthesis with a methanol to gasoline (MTG) process in a single reactor bed. A commercial Cu/ZnO/Al2O3 catalyst, utilized industrially for the synthesis of methanol at 220-280°C, suffers from a rapid deactivation when the reaction is conducted at high temperature (>320°C). On the contrary, a Pd/ZnO/Al2O3 catalyst was found to be highly stable for methanol and DME synthesis at 380°C. The Pd/ZnO/Al2O3 catalyst was thus further investigated for methanol and DME synthesis at P=34-69 bars, T= 250-380°C, GHSV= 5 000-18 000 h-1, and molar feeds H2/CO= 1, 2, and 3. Selectivity to DME increased with decreasing operating temperature, and increasing operating pressure. Increased GHSV's and H2/CO syngas feed ratios also enhanced DME selectivity. Undesirable CH4 formation was observed, however, can be minimized through choice of process conditions and by catalyst design. By studying the effect of the Pd loading and the Pd:Zn molar ratio the formulation of the Pd/ZnO/Al2O3 catalyst was optimized. A catalyst with 5% Pd and a Pd:Zn molar ratio of 0.25:1 has been identified as the preferred catalyst. Results indicate that PdZn particles are more active than Pdş particles for the synthesis of methanol and less active for CH4 formation. A correlation between DME selectivity and the concentration of acid sites of the catalysts has been established. Hence, two types of sites are required for the direct conversion of syngas to DME: 1) PdZn particles are active for the synthesis of methanol from syngas, and 2) acid sites which are active for the conversion of methanol to DME. Additionally, CO2 formation was problematic as PdZn was found to be active for the water-gas-shift (WGS) reaction, under all the conditions evaluated.
Index of Subjects Abbreviations ix,203-6
Hall, Christopher
90 Absorption of light 110-11,137-9,168 Accelerated testing 139 Acetal 14, 204, 206, see also, polymer 156-7,216 Allyl diglycol carbonate 113, 165-6 Allyl resins 165 Alumina 95 Aluminium 58 modulus 57,70,92 Bulk polymerisation 31 Butadiene 5,167,169,217 Butane 11 Butene 219 Butyl acetate 181
Chang, E.J.; Leiby, S.M. (SRI International, Menlo Park, CA (US))
In this article three scenarios to evaluate the effect of etherification on gasoline production and quality are reviewed: Base case FCC/C{sub 4} alkylation complex - FCC unit operation for maximum gasoline yield, MTBE unit added to base case FCC unit operation and MTBE unit added to maximum olefins FCC unit operation. Details of the FCC, MTBE and C{sub 4} alkylation operations used in this article are reviewed, followed by a discussion of overall results.
A Low-Carbon Fuel Standard for California Part 1: Technical Analysis
methyl-tertiary butyl ether (MTBE), from gasoline by 2004.MTBE was used to meet a requirement for gasoline to containbeginning in 2002, replacing MTBE with ethanol. According to
Emissions of volatile organic compounds inferred from airborne flux measurements over a megacity
Karl, T.; Apel, E.; Hodzic, A.; Riemer, D. D; Blake, D. R; Wiedinmyer, C.
methyl-tertiary-butyl- ether (MTBE) and the biomass burningfrom all source categories. MTBE is a gasoline additive andwith the fuel tracer MTBE (e.g. 0.82 for MTBE/benzene).
Chemical evolution of volatile organic compounds in the outflow of the Mexico City Metropolitan area
Methanol Ethanol Acetone MEK MTBE CO Methane UCI UCI TOGA/methyl tertiary butyl ether (MTBE), and toluene all ratioedthe observed decay. For MTBE, also a species that is not
Soil type, crop and irrigation technique affect nitrogen leaching to groundwater
Letey, John; Vaughan, Peter
water contamination with MTBE (methyl tertiary-butyl ether,that areas vulnerable to MTBE are also vulner- able tothat affect the movement of MTBE. If only a small amount of
Measurements of volatile organic compounds at a suburban ground site (T1) in Mexico City during the MILAGRO 2006 campaign: measurement comparison, emission ratios, and source attribution
methyl tert-butyl ether (MTBE) at 57 amu has been previouslyby a fragment of MTBE (62%) with minor contributions fromFortner and Knighton, 2008). MTBE also in- terfered (16%)
Characterization of trace gases measured over Alberta oil sands mining operations: 76 speciated C2-C10 volatile organic compounds (VOCs), CO2, CH4, CO, NO, NO2, NOy, O3 and SO2
methyl tertiary- butyl ether (MTBE) and its effect on plasmaand three VOCs (propyne, furan, MTBE) remained below their 3Ethanol Acetone MEK MAC MVK MTBE Furan CH 3 OH C 2 H 5 OH C
Synthesis of higher alcohols on copper catalysts supported on alkali-promoted basic oxides
Iglesia, Enrique
-butyl-ether (MTBE) after isobutanol dehydration to form isobutene. An equimolar ratio of methanol to isobutanol would be preferred for MTBE synthesis. Methanol and higher alcohols can also be used for direct blending
A Low-Carbon Fuel Standard for California, Part 1: Technical Analysis
Farrell, Alexander E.; Sperling, Dan
methyl-tertiary butyl ether (MTBE), from gasoline by 2004.MTBE was used to meet a requirement for gasoline to containbeginning in 2002, replacing MTBE with ethanol. According to
Factors influencing biological treatment of MTBE contaminated ground water
Stringfellow, William T.; Hines Jr., Robert D.; Cockrum, Dirk K.; Kilkenny, Scott T.
Methyl tertiary-butyl ether (MTBE) biodegradation in batchCometabolic degradation of MTBE by a cyclohexane-oxidizingof 49 Biological Treatment of MTBE Fortin, N. Y. , and M. A.
Finding the missing stratospheric Bry: a global modeling study of CHBr3 and CH2Br2
Methanol Ethanol Acetone MEK MTBE CO Methane UCI UCI TOGA/methyl tertiary butyl ether (MTBE), and toluene all ratioedthe observed decay. For MTBE, also a species that is not
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, Aug. 2004, p. 47204726 Vol. 70, No. 8 0099-2240/04/$08.00 0 DOI: 10.1128/AEM.70.8.47204726.2004
Alvarez, Pedro J.
contamination of surface and groundwater resources by the gasoline oxygenate methyl tert-butyl ether (MTBE) is leading to its phaseout. Ethanol, a likely candidate to substitute MTBE, is increasingly being used
Assessing the Effectiveness of California's Underground Storage Tank Annual Inspection Rate Requirements
Cutter, W. Bowman
Methyl Tert-Butyl Ether (MTBE), a gasoline additive. Thefor the lion's share of MTBE contamination, as well asIn response to the MTBE crisis, California increased the
Trichloroethene Removal From Waste Gases in Anaerobic Biotrickling Filters Through Reductive Dechlorination
Popat, Sudeep Chandrakant
methyl tert-butyl ether (MTBE) vapors into water was used.MTBE is highly soluble in water (dimensionless Henry'sgas stream was laden with MTBE vapors (200-300 mg m -3 )
Life-Cycle Water Impacts of U.S. Transportation Fuels
Scown, Corinne Donahue
Drinking Water: Methyl Tertiary Butyl Ether (MTBE).http://www.epa.gov/mtbe/water.htm (11/30/10), Chiu, Y. W. ;LCFS LCI LP LPG MED MRO MSF MTBE MWD MWDOC NAICS NERC NETL
Gas Chromatography -Mass Spectrometry
Nizkorodov, Sergey
, ethanol and methyl-t-butyl ether (MTBE). Due to some gasoline leakage from underground storage tanks into drinking water supplies, MTBE has been, or is in the process of being phased out in many areas. The octane
Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]
Report The Form EIA-819, "Monthly Oxygenate Report" provides production data for fuel ethanol and methyl tertiary butyl ether (MTBE). End-of-month stock data held at ethanol...
Pyrolysis of Organic Molecules Relevant to Combustion as Monitored by Photoionization Time-of-Flight Mass Spectrometry
Weber, Kevin Howard
2-ethoxy-2-methylpropane, ETBE) have since been used astert-butyl ethers TAME, ETBE, and MTBE continue to be usedMTBE, 27-34 TAME, 31-34 and ETBE 31-34 are reported to react
7198 J. Org. Chem. 1995,60, 7198-7208 Gas Phase Decomposition of Conjugate Acid Ions of Simple
Morton, Thomas Hellman
(MTBE),ethyl (ETBE),n-propyl,isopropyl,and isobutyl tert-butyl ethers have been examined experimentally spectroscopy (MIKES) experiments on deuterated ions from MTBE and ETBE. Mechanistic possibilities are probed tert-amyl ether and its deuterated analogues. Protonated MTBE displays a single unimolecular
International Journal of Mass Spectrometry 249250 (2006) 303310 Pyrolysis of 2-methoxy-2,3,3-trimethylbutane (MTMB) monitored by
Morton, Thomas Hellman
used fuel oxygenates MTBE and TAME), the predominance of bond homolysis at temperatures >900 K suggests homologues  methyl tert-butyl ether (MTBE) and tert-amyl methyl ether (TAME)  present a new set of problems discussed as alternatives to MTBE and TAME, because they are expected to be much less soluble in water. More
Published Ahead of Print 1 July 2011. 2011, 193(17):4549. DOI: 10.1128/JB.00415-11.J. Bacteriol.
Alvarez-Cohen, Lisa
Laboratory, Joint Genome Institute, Biosciences Division Genome Science B6, Los Alamos, New Mexico 875454 ; U and energy source (9, 10, 11, 14). This strain can also grow on other ethers (e.g., 2-methyl-1,3- dioxolane and butyl methyl ether), alcohols, and benzene as the sole carbon and energy source, and it can grow
Combined 3D-QSAR, molecular docking and molecular dynamics study on thyroid hormone activity of hydroxylated polybrominated diphenyl ethers to thyroid receptors ?
Li, Xiaolin [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046 (China)] [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046 (China); Ye, Li [Suzhou NeuPharma Co.,Ltd, Suzhou 215123 (China)] [Suzhou NeuPharma Co.,Ltd, Suzhou 215123 (China); Wang, Xiaoxiang [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046 (China)] [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046 (China); Wang, Xinzhou [Suzhou NeuPharma Co.,Ltd, Suzhou 215123 (China)] [Suzhou NeuPharma Co.,Ltd, Suzhou 215123 (China); Liu, Hongling [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046 (China)] [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046 (China); Zhu, Yongliang [Suzhou NeuPharma Co.,Ltd, Suzhou 215123 (China)] [Suzhou NeuPharma Co.,Ltd, Suzhou 215123 (China); Yu, Hongxia, E-mail: firstname.lastname@example.com [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046 (China)] [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046 (China)
Several recent reports suggested that hydroxylated polybrominated diphenyl ethers (HO-PBDEs) may disturb thyroid hormone homeostasis. To illuminate the structural features for thyroid hormone activity of HO-PBDEs and the binding mode between HO-PBDEs and thyroid hormone receptor (TR), the hormone activity of a series of HO-PBDEs to thyroid receptors ? was studied based on the combination of 3D-QSAR, molecular docking, and molecular dynamics (MD) methods. The ligand- and receptor-based 3D-QSAR models were obtained using Comparative Molecular Similarity Index Analysis (CoMSIA) method. The optimum CoMSIA model with region focusing yielded satisfactory statistical results: leave-one-out cross-validation correlation coefficient (q{sup 2}) was 0.571 and non-cross-validation correlation coefficient (r{sup 2}) was 0.951. Furthermore, the results of internal validation such as bootstrapping, leave-many-out cross-validation, and progressive scrambling as well as external validation indicated the rationality and good predictive ability of the best model. In addition, molecular docking elucidated the conformations of compounds and key amino acid residues at the docking pocket, MD simulation further determined the binding process and validated the rationality of docking results. -- Highlights: ? The thyroid hormone activities of HO-PBDEs were studied by 3D-QSAR. ? The binding modes between HO-PBDEs and TR? were explored. ? 3D-QSAR, molecular docking, and molecular dynamics (MD) methods were performed.
Mechanistic studies of coenzyme B?? model systems
Robinson, John Walter
involved a 2-step synthesis of first, tert-butyl chloromethyl ether, and secondly, alkylation of the ether with dimethyl methyl malonate. The synthesis of tert-butyl chloromethyl ether proved more diffucult than anticipated. After irradiating a soludon... PAGE 17 2. 2. 2 The Reaction Products: 0, S diethyl methyl succinate and 0, S diethyl dimethyl malonate 2. 2. 2. 1 0, S diethyl methyl succinate 2. 2. 2. 2 0, S diethyl dimethyl malonate 2. 2. 3 Radical Generation and Trapping 2. 4 Summary 2. 5...
Race to license new MTBE and TAME routes heats up
Rotman, D.
With refineries and petrochemical manufacturers continuing to gear up production of oxygenates for use in reformulated fuels, new routes to methyl tert-butyl ether (MTBE) and tert-amyl methyl ether (TAME) are clearly hot items in the licensing market. And probably nowhere has the competition become as intense as in offerings for skeletal isomerization technologies to boost ethers production from fluid catalytic cracking and steam cracking.
Oxygenates du`jour...MTBE? Ethanol? ETBE?
Wolfe, R.
There are many different liquids that contain oxygen which could be blended into gasoline. The ones that have been tried and make the most sense are in the alcohol (R-OH) and ether (R-O-R) chemical family. The alcohols considered are: methanol (MeOH), ethanol (EtOH), tertiary butyl alcohol (TBA). The ethers are: methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), tertiary amyl methyl ether (TAME), tertiary amyl ethyl ether (TAEE), di-isopropyl ether (DIPE). Of the eight oxygenates listed above, the author describes the five that are still waiting for widespread marketing acceptance (methanol, TBA, TAME, TAEE, and DIPE). He then discusses the two most widely used oxygenates in the US, MTBE and ethanol, along with the up-and-coming ethanol ether, ETBE. Selected physical properties for all of these oxygenates can be found in Table 2 at the end of this paper. A figure shows a simplified alcohol/ether production flow chart for the oxygenates listed above and how they are interrelated.
LANXESS Global Butyl Rubber Research Facility
Denham, Graham
at the University of Western Ontario Research Park in Sarnia. Through its subsidiary Bluewater Chemicals, Bio
Quercetin 3-O-methyl ether protects FL83B cells from copper induced oxidative stress through the PI3K/Akt and MAPK/Erk pathway
Tseng, Hsiao-Ling, E-mail: firstname.lastname@example.com [Department of Life Sciences, Tzu Chi University, Hualien, Taiwan (China)] [Department of Life Sciences, Tzu Chi University, Hualien, Taiwan (China); Li, Chia-Jung, E-mail: email@example.com [Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan (China)] [Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan (China); Huang, Lin-Huang, E-mail: email@example.com [School of Medicine, Institute of Traditional Medicine, National Yang-Ming University, Taipei, Taiwan (China)] [School of Medicine, Institute of Traditional Medicine, National Yang-Ming University, Taipei, Taiwan (China); Chen, Chun-Yao, E-mail: email@example.com [Department of Life Sciences, Tzu Chi University, Hualien, Taiwan (China)] [Department of Life Sciences, Tzu Chi University, Hualien, Taiwan (China); Tsai, Chun-Hao, E-mail: firstname.lastname@example.com [Department of Life Sciences, Tzu Chi University, Hualien, Taiwan (China)] [Department of Life Sciences, Tzu Chi University, Hualien, Taiwan (China); Lin, Chun-Nan, E-mail: firstname.lastname@example.com [Faculty of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan (China) [Faculty of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Department of Biological Science and Technology, School of Medicine, China Medical University, Taichung, Taiwan (China); Hsu, Hsue-Yin, E-mail: email@example.com [Department of Life Sciences, Tzu Chi University, Hualien, Taiwan (China)] [Department of Life Sciences, Tzu Chi University, Hualien, Taiwan (China)
Quercetin is a bioflavonoid that exhibits several biological functions in vitro and in vivo. Quercetin 3-O-methyl ether (Q3) is a natural product reported to have pharmaceutical activities, including antioxidative and anticancer activities. However, little is known about the mechanism by which it protects cells from oxidative stress. This study was designed to investigate the mechanisms by which Q3 protects against Cu{sup 2+}-induced cytotoxicity. Exposure to Cu{sup 2+} resulted in the death of mouse liver FL83B cells, characterized by apparent apoptotic features, including DNA fragmentation and increased nuclear condensation. Q3 markedly suppressed Cu{sup 2+}-induced apoptosis and mitochondrial dysfunction, characterized by reduced mitochondrial membrane potential, caspase-3 activation, and PARP cleavage, in Cu{sup 2+}-exposed cells. The involvement of PI3K, Akt, Erk, FOXO3A, and Mn-superoxide dismutase (MnSOD) was shown to be critical to the survival of Q3-treated FL83B cells. The liver of both larval and adult zebrafish showed severe damage after exposure to Cu{sup 2+} at a concentration of 5 ?M. Hepatic damage induced by Cu{sup 2+} was reduced by cotreatment with Q3. Survival of Cu{sup 2+}-exposed larval zebrafish was significantly increased by cotreatment with 15 ?M Q3. Our results indicated that Cu{sup 2+}-induced apoptosis in FL83B cells occurred via the generation of ROS, upregulation and phosphorylation of Erk, overexpression of 14-3-3, inactivation of Akt, and the downregulation of FOXO3A and MnSOD. Hence, these results also demonstrated that Q3 plays a protective role against oxidative damage in zebrafish liver and remarked the potential of Q3 to be used as an antioxidant for hepatocytes. Highlights: ? Protective effects of Q3 on Cu{sup 2+}-induced oxidative stress in vitro and in vivo. ? Cu{sup 2+} induced apoptosis in FL83B cells via ROS and the activation of Erk. ? Q3 abolishes Cu{sup 2+}-induced apoptosis through the PI3K/Akt and MAPK/Erk pathway.
Polybrominated diphenyl ethers in e-waste: Level and transfer in a typical e-waste recycling site in Shanghai, Eastern China
Li, Yue; Duan, Yan-Ping, E-mail: email@example.com; Huang, Fan; Yang, Jing; Xiang, Nan; Meng, Xiang-Zhou; Chen, Ling
Highlights: • PBDEs were detected in the majority of e-waste. • PBDEs were found in TVs made in China after 1990. • The levels of ?PBDEs in e-waste made in Japan far exceed the threshold limit of RoHS. • The inappropriate recycling and disposal of e-waste is an important source of PBDEs. - Abstract: Very few data for polybrominated diphenyl ethers (PBDEs) were available in the electronic waste (e-waste) as one of the most PBDEs emission source. This study reported concentrations of PBDEs in e-waste including printer, rice cooker, computer monitor, TV, electric iron and water dispenser, as well as dust from e-waste, e-waste dismantling workshop and surface soil from inside and outside of an e-waste recycling plant in Shanghai, Eastern China. The results showed that PBDEs were detected in the majority of e-waste, and the concentrations of ?PBDEs ranged from not detected to 175 g/kg, with a mean value of 10.8 g/kg. PBDEs were found in TVs made in China after 1990. The mean concentrations of ?PBDEs in e-waste made in Korea, Japan, Singapore and China were 1.84 g/kg, 20.5 g/kg, 0.91 g/kg, 4.48 g/kg, respectively. The levels of ?PBDEs in e-waste made in Japan far exceed the threshold limit of RoHS (1.00 g/kg). BDE-209 dominated in e-waste, accounting for over 93%. The compositional patterns of PBDEs congeners resembled the profile of Saytex 102E, indicating the source of deca-BDE. Among the samples of dust and surface soil from a typical e-waste recycling site, the highest concentrations of ?{sub 18}PBDEs and BDE-209 were found in dust in e-waste, ranging from 1960 to 340,710 ng/g and from 910 to 320,400 ng/g, which were 1–2 orders of magnitude higher than other samples. It suggested that PBDEs released from e-waste via dust, and then transferred to surrounding environment.
13-03-09 9:37 PMModernity, the Cold War, and New Whig Histories of Ideas, Pt. 2 | Ether Wave Propaganda Page 1 of 4http://etherwave.wordpress.com/2012/10/21/modernity-the-cold-war-and-new-whig-histories-of-ideas-pt-2/
Solovey, Mark
13-03-09 9:37 PMModernity, the Cold War, and New Whig Histories of Ideas, Pt. 2 | Ether Wave Propaganda Page 1 of 4http://etherwave.wordpress.com/2012/10/21/modernity-the-cold-war-and-new-whig-histories-of-ideas-pt-2/ Modernity, the Cold War, and New Whig Histories of Ideas, Pt. 2 October 21, 2012 Posted
12-11-24 7:47 PMModernity, the Cold War, and New Whig Histories of Ideas, Pt. 3 Ether Wave Propaganda Page 1 of 6http://etherwave.wordpress.com/2012/11/17/modernity-the-cold-war-and-new-whig-histories-of-ideas-pt-3/
Solovey, Mark
12-11-24 7:47 PMModernity, the Cold War, and New Whig Histories of Ideas, Pt. 3 « Ether Wave Propaganda Page 1 of 6http://etherwave.wordpress.com/2012/11/17/modernity-the-cold-war-and-new-whig-histories-of-ideas-pt-3/ Modernity, the Cold War, and New Whig Histories of Ideas, Pt. 3 November 17, 2012 Posted
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Solovey, Mark
13-03-09 9:32 PMModernity, the Cold War, and New Whig Histories of Ideas, Pt. 1 | Ether Wave Propaganda Page 1 of 6http://etherwave.wordpress.com/2012/09/22/modernity-the-cold-war-and-new-whig-histories-of-ideas-pt-1/ Modernity, the Cold War, and New Whig Histories of Ideas, Pt. 1 September 22, 2012 Posted
sup 13 C, sup 17 O, and sup 14 N NMR spectroscopic studies of a series of mixed isocyanide/carbonyl complexes of tungsten: W(CO) sub 6-n (CNR) sub n (R = tert-butyl, p tolyl; n = 1-3)
Guy, M.P.; Coffer, J.L.; Rommel, J.S.; Bennett, D.W. (Univ. of Wisconsin, Milwaukee (USA))
{sup 13}C, {sup 17}O, and {sup 14}N NMR spectra for the tungsten isocyanide complexes W(CO){sub 6-n}(CNR){sub n} (R = tert-butyl, p-tolyl; n = 1-3) have been obtained and the magnitudes of the corresponding chemical shifts utilized as a probe of differences in electronic structure. Comparisons of {delta}({sup 17}O) with {delta}({sup 13}CO) and of {delta}(C{sup 14}N) with {nu}(CN), or {delta}({sup 13}CO) are shown to confirm the better net donor ability of the aliphatic isocyanide over the aromatic isocyanide and illustrate an increased amount of charge density available at the metal center when CO is successively replaced with CNR. Marked differences in {sup 14}N quadrupolar relaxation times are observed between aromatic and aliphatic isocyanides, suggesting that the aromatic ring is involved in the M-L {pi} system. 19 references, 5 figures, 3 tables.
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Solovey, Mark
13-03-09 9:30 PMCold War Social Science and the Rubric of the "Cold War" | Ether Wave Propaganda Page 1 of 6http://etherwave.wordpress.com/2012/09/06/cold-war-social-science-and-the-rubric-of-the-cold-war/ Cold War Social Science and the Rubric of the "Cold War" September 6, 2012 Posted by Will Thomas in EWP
NIOSH Manual of Analytical Methods (third edition). Fourth supplement
Not Available
The NIOSH Manual of Analytical Methods, 3rd edition, was updated for the following chemicals: allyl-glycidyl-ether, 2-aminopyridine, aspartame, bromine, chlorine, n-butylamine, n-butyl-glycidyl-ether, carbon-dioxide, carbon-monoxide, chlorinated-camphene, chloroacetaldehyde, p-chlorophenol, crotonaldehyde, 1,1-dimethylhydrazine, dinitro-o-cresol, ethyl-acetate, ethyl-formate, ethylenimine, sodium-fluoride, hydrogen-fluoride, cryolite, sodium-hexafluoroaluminate, formic-acid, hexachlorobutadiene, hydrogen-cyanide, hydrogen-sulfide, isopropyl-acetate, isopropyl-ether, isopropyl-glycidyl-ether, lead, lead-oxide, maleic-anhydride, methyl-acetate, methyl-acrylate, methyl-tert-butyl ether, methyl-cellosolve-acetate, methylcyclohexanol, 4,4'-methylenedianiline, monomethylaniline, monomethylhydrazine, nitric-oxide, p-nitroaniline, phenyl-ether, phenyl-ether-biphenyl mixture, phenyl-glycidyl-ether, phenylhydrazine, phosphine, ronnel, sulfuryl-fluoride, talc, tributyl-phosphate, 1,1,2-trichloro-1,2,2-trifluoroethane, trimellitic-anhydride, triorthocresyl-phosphate, triphenyl-phosphate, and vinyl-acetate.
New etherification process commercialized in Finland
The phase-out of leaded fuels in Europe, Asia, and parts of Africa and Latin America is increasing demand for octane and octane-bearing fuel components such as ethers. Early solutions to the problem of increasing octane while reducing tailpipe emissions involved use of methyl tertiary butyl ether (MTBE). According to Neste, using both tertiary amyl methyl ether (TAME) and MTBE can give refiners increased blending flexibility for volatility control. But the economics associated with TAME production often make TAME units difficult to justify. The paper discusses the NExTAME process, the unit at the Porvoo refinery and process improvements.
Synthetic approaches to the activation of substituted 2-methyl pyridines
Cancanon, Fernadina de la Caridad
(21%), 148 (42%), 135 (100%), 1 08 (35%), 93 ( 43%), 83 (38%), 55 (49%), 41 (48%), 29 (27 la) 2-[N(4, 4-Dimethyl-2, 6-dioxopiperidinyl))-6-pycolyl-tert-butytdi phenylsilyl ether (26) O Bu'Ph zSi0 N N The same procedure for the preparation.... 14%, ' N, 16. 52%. Attempted ring opening of 2-[N-(4, 4-dimethyl-2, 6-dioxo piperidinyl)]-6- picolyl-tert-butyl diphenylsilyl ether (26) with 6-amino-2-pyridine methanol-fert-butyldiphenylsilyl ether (22) The cyclic imide 26 (0. 487g, 0. 001 mole...
Motor Gasoline Outlook and State MTBE Bans
Reports and Publications (EIA)
The U.S. is beginning the summer 2003 driving season with lower gasoline inventories and higher prices than last year. Recovery from this tight gasoline market could be made more difficult by impending state bans on the blending of methyl tertiary butyl ether (MTBE) into gasoline that are scheduled to begin later this year.
Gasoline and Diesel Fuel Update (EIA)
3,054 Fuel Ethanol (FE) 1,019 97 1,116 2,133 528 393 3,054 Methyl Tertiary Butyl Ether (MTBE) 561 0 561 0 0 0 0 All Other Oxygenates a 0 0 0 0 0 0 0 Motor Gasoline Blend. Comp....
Alvarez, Pedro J.
as a replacement for the gasoline oxygenate, methyl tert-butyl ether MTBE , may lead to indirect impacts related facilitate the migration of pre-existing contamination. MTBE 25 mg/L influent was not degraded inlet by one order of magnitude relative to columns fed BTEX alone or with MTBE. However, 16S
Environmental Toxicology and Chemistry, Vol. 21, No. 12, pp. 26312639, 2002 Printed in the USA
Alvarez, Pedro J.
--Aquifer microcosms were used to determine how ethanol and methyl-tert-butyl ether (MtBE) affect monoaromatic compared to benzene, which was degraded only under aerobic conditions. The MtBE was not degraded within 100 to phase out MtBE as a gasoline oxy- genate is likely to significantly increase the use of ethanol
Role of Volatilization in Changing TBA and MTBE Concentrations at
Role of Volatilization in Changing TBA and MTBE Concentrations at MTBE-Contaminated Sites J U A N tertiary butyl ether (MTBE) added to gasoline. Frequent observations of high TBA, and especially rising TBA/MTBE of MTBE to TBA. Typically overlooked is the role of volatilization in the attenuation of these chemicals
Critical Reviews in Environmental Science and Technology, 00(0):000000 (2001) 1064-3389/01/$.50
Alvarez, Pedro J.
water contamination by methyl tert-butyl ether (MTBE) have made policymakers more cognizant of the need reformulated gasoline (RFG) (2% oxygen) year-round to reduce emissions that contribute to ozone formation. MTBE-making process that lead to the widespread use of MTBE over the last decade is now quite controversial (BRP, 1999
Author's personal copy Automobile proximity and indoor residential concentrations of BTEX and MTBE
Siegel, Jeffrey
Author's personal copy Automobile proximity and indoor residential concentrations of BTEX and MTBE to indoor benzene and MTBE concentrations appeared to have been dominated by car exhaust concentrations of other BTEX components and methyl tert-butyl ether (MTBE) have been reported [5,6]. Up until
I. Pt-Catalyzed Tandem Epoxide Fragmentation/Pentannulation of Propargylic Esters II. Progress Toward the Kopsia Family of Indole Alkaloids
Pujanauski, Brian Gerard
methyl t-butyl ether (MTBE), a much more environmentallyPhMe, reflux POCl 3 , Et 3 N CN MTBE Scheme 3.3: OptimizedO H NH POCl 3 , Et 3 N CN MTBE 1-Isocyanocyclohex-1-ene (
Biotreatment of groundwater contaminated with MTBE: interaction of common environmental co-contaminants
Biotreatment of groundwater contaminated with MTBE: interaction of common environmental co November 2005 Key words: aerobic, biodegradation, BTEX, co-contaminant, MTBE, TBA Abstract Contamination of groundwater with the gasoline additive methyl tert-butyl ether (MTBE) is often accompanied by many aromatic
Canada could get three MTBE plants
Anderson, E
This article reports on the proposed development of three methyl tert-butyl ether (MTBE) plants in Canada. MTBE is used as an oxygenated fuel additive. The author discusses how demand for MTBE is increasing due to the regulation of leaded gasoline by the U.S. and Canadian governments. The exportation of MTBE from Canada to the U.S. is highlighted.
Patzek, Tadeusz W.
, and by law refiners must add to gasoline oxygenating additives like methyl ter- tiary-butyl ether (MTBE better, thus reducing carbon monoxide and other emissions. MTBE is the fuel oxygenate preferred by oil as gaso- line, mixes well with gasoline, and does not increase the gasoline vapor pressure. MTBE has
Atmosphere-Water Interaction of Chloroform, Toluene, and MTBE in Small Perennial Urban Streams
Atmosphere-Water Interaction of Chloroform, Toluene, and MTBE in Small Perennial Urban Streams-butyl ether (MTBE) are frequently detected VOCs in the atmosphere, surface water, and ground water in urban not be the predominant source of chloroform and toluene in the two urban streams. In contrast, MTBE may be coming from
By Martman Cohen News Office staff
Lovley, Derek
tertiary butyl ether, or MTBE (another hazardous gasoline component that is hazardous to health the benzene-removal technol- ogy to sites contaminated with MTBE. That gasoline additive tends to mi- grate of MTBE- contaminated sites from around the U.S. By simulating an anaerobic pro- cess similar to what
UMass builds bugs to eat MTBE ByAuriaCimino
Lovley, Derek
UMass builds bugs to eat MTBE ByAuriaCimino STAfFWRITER An area university's process to destroy with methyl tertiary butyl ether (MTBE), which is found in gasoline. Once the first field trial is complete in particular has suffered from MTBE contamination because of the abundance of groundwater in the state, said
Fourier Transform Infrared Spectroscopy
Nizkorodov, Sergey
FTIR - 1 Fourier Transform Infrared Spectroscopy FTIR DETERMINATION OF MTBE IN GASOLINE AND ETHANOL FTIR DETERMINATION OF MTBE IN GASOLINE AND ETHANOL IN VODKA AND MOUTHWASH INTRODUCTION As a part has contained MTBE (methyl tertÂbutyl ether) as its primary oxygenate. However, there has been
MTBE still facing pressure from ethanol under latest fuel proposal
Lucas, A.
The US EPA's finalized reformulated gasoline rule, part of Phase II of the 1990 Clean Air Act, signals a possible turnaround for the sluggish methyl tert-butyl ether (MTBE) market. But if a 30% renewable fuels proposal favoring ethanol passes, pressure could continue for MTBE.
Gasoline and Diesel Fuel Update (EIA)
Fuel Ethanol (FE) 1,229 108 1,337 2,369 724 497 3,590 Methyl Tertiary Butyl Ether (MTBE) 292 0 292 0 0 0 0 All Other Oxygenates a 0 0 0 0 0 0 0 Motor Gasoline Blend. Comp....
Dozier, Monty; Lesikar, Bruce J.
Methyl tertiary-butyl ether, a gasoline additive commonly known as MTBE, can contaminate ground water and cause health problems for those exposed to it for a long time. However, filtering devices can remove this and other additives from well water...
Physico-chemical and biological characterization of an aquifer polluted with Yves Benoit (1)
Paris-Sud XI, Université de
the use of biofuels through tax incentives, including the addition of bioethanol to gasoline. Some tertiary-butyl ether (ETBE) using bioethanol. ETBE is presently the main way of the bioethanol utilization bioethanol raw material. In Europe, the maximal authorized ETBE concentration in gasoline has now reached 22
High Temperature, Low Relative Humidity, Polymer-type Membranes Based on Disulfonated Poly(arylene ether) Block and Random Copolymers Optionally Incorporating Protonic Conducting Layered Water insoluble Zirconium Fillers
McGrath, James E.; Baird, Donald G.
Our research group has been engaged in the past few years in the synthesis of biphenol based partially disulfonated poly(arylene ether sulfone) random copolymers as potential PEMs. This series of polymers are named as BPSH-xx, where BP stands for biphenol, S stands for sulfonated, H stands for acidified and xx represents the degree of disulfonation. All of these sulfonated copolymers phase separate to form nano scale hydrophilic and hydrophobic morphological domains. The hydrophilic phase containing the sulfonic acid moieties causes the copolymer to absorb water. Water confined in hydrophilic pores in concert with the sulfonic acid groups serve the critical function of proton (ion) conduction and water transport in these systems. Both Nafion and BPSH show high proton conductivity at fully hydrated conditions. However proton transport is especially limited at low hydration level for the BPSH random copolymer. It has been observed that the diffusion coefficients of both water and protons change with the water content of the pore. This change in proton and water transport mechanisms with hydration level has been attributed to the solvation of the acid groups and the amount of bound and bulk-like water within a pore. At low hydration levels most of the water is tightly associated with sulfonic groups and has a low diffusion coefficient. This tends to encourage isolated domain morphology. Thus, although there may be significant concentrations of protons, the transport is limited by the discontinuous morphological structure. Hence the challenge lies in how to modify the chemistry of the polymers to obtain significant protonic conductivity at low hydration levels. This may be possible if one can alter the chemical structure to synthesize nanophase separated ion containing block copolymers. Unlike the BPSH copolymers, where the sulfonic acid groups are randomly distributed along the chain, the multiblock copolymers will feature an ordered sequence of hydrophilic and hydrophobic segments. If, like in Nafion, connectivity is established between the hydrophilic domains in these multiblock copolymers, they will not need as much water, and hence will show much better protonic conductivity than the random copolymers (with similar degree of sulfonation, or IEC) at partially hydrated conditions. The goal of this research is to develop a material suitable for use as a polymer electrolyte membrane which by the year 2010 will meet all the performance requirements associated with fuel cell operation at high temperatures and low relative humidity, and will out-perform the present standard Nafion{reg_sign}. In particular, it is our objective to extend our previous research based on the use of thermally, oxidatively, and hydrolytically, ductile, high Tg ion containing polymers based on poly(arylene ethers) to the production of polymer electrolyte membranes which will meet all the performance requirements in addition to having an areal resistance of < 0.05 ohm-cm{sup 2} at a temperature of up to 120 C, relative humidity of 25 to 50%, and up to 2.5 atm total pressure. In many instances, our materials already out performs Nafion{reg_sign}, and it is expected that with some modification by either combining with conductive inorganic fillers and/or synthesizing as a block copolymer it will meet the performance criteria at high temperatures and low relative humidity. A key component in improving the performance of the membranes (and in particular proton conductivity) and meeting the cost requirements of $40/m{sup 2} is our development of a film casting process, which shows promise for generation of void free thin films of uniform thickness with controlled polymer alignment and configuration.
Saving Energy and Reducing Emissions from the Regeneration Air System of a Butane Dehydrogenation Plant
John, T. P.
at 900 to 1100°F containing CO and VOC. By installing a furnace/heat recovery steam generator, Texas Petrochemicals achieved significant reductions of VOC, CO, and NOx, along with energy savings....
Hydrodesulfurization of Thiophene and Benzothiophene to Butane and Ethylbenzene by a Homogeneous Iridium
Jones, William D.
in a dihydrogen environment, affording the hydrogenated organic products plus ad- sorbed sulfur or H2S. While many impurities such as thio- phenes, mercaptans, and quinolines are removed, mak- ing the oil amenable to further refining. Removal of the sulfur compounds, in particular, decreases the contribu- tions to acid rain
The determination of compressibility factors of gaseous butane-nitrogen mixtures in the gas phase
Evans, Robert Buckner
. of mercury ejected from the mercury pump. TABLE OF NOMENCLATURE T R,: . . . . ................... . mercury pump reading expressed as apparent cc. of mercury remaining in the pump. R ..............................the gas constant - units as applicable... to a reading of -1, then rotated forward one turn. The calibration proceeded by measuring volume increments every ten turns. Ten minutes were allowed between increments to minimize thermal variations. The volume of mercury i ?-fO ejected at h5 C...
==================== !"#$%&'()*+,-+./,0)12 Development of Micro Ejector for Butane Catalytic Combustor
Kasagi, Nobuhide
pumps ambient air to the combustion chamber by utilizing the vapor pressure of liquified fuel. Catalytic with the excessive heat of the exhaust gas. The advantage of using ejector is that air-entrainment is achieved without an additional air container or a micro pump, and thus the system should be simple, safe
Polybrominated dibenzo-p-dioxins/dibenzofurans and polybrominated diphenyl ethers in soil, vegetation, workshop-floor dust, and electronic shredder residue from an electronic waste recycling facility and in soils from a chemical industrial complex in eastern China
Jing Ma; Rudolf Addink; Sehun Yun; Jinping Cheng; Wenhua Wang; Kurunthachalam Kannan [Shanghai Jiao Tong University, Shanghai (China). School of Environmental Science and Engineering
In this study, 11 2,3,7,8-substituted PBDD/Fs and 10 polybrominated diphenyl ether (PBDE) congeners were determined in electronic shredder waste, workshop-floor dust, soil, and leaves (of plants on the grounds of the facility) from a large-scale electronic wastes (e-waste) recycling facility and in surface soil from a chemical-industrial complex (comprising a coke-oven plant, a coal-fired power plant, and a chlor-alkali plant) as well as agricultural areas in eastern China. Total PBDD/F concentrations in environmental samples were in the range of 113-818 pg/g dry wt (dw) for leaves, 392-18,500 pg/g dw for electronic shredder residues, 716-80,0000 pg/g dw for soil samples, and 89,600-14,3000 pg/g dw for workshop-floor dust from the e-waste recycling facility and in a range from nondetect (ND) to 427 pg/g dw in soil from the chemical-industrial complex. The highest mean concentrations of total PBDD/Fs were found in soil samples and workshop-floor dust from the e-waste recycling facility. The dioxin-like toxic equivalent (measured as TEQ) concentrations of PBDD/Fs were greater than the TEQs of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) reported in our previous study for the same set of samples. The concentrations of PBDFs were several orders of magnitude higher than the concentrations of PBDDs in samples from the e-waste facility or from soil from the chemical-industrial complex. A significant correlation was found between the concentrations of {Sigma}PBDD/Fs and {Sigma}PBDEs (r = 0.769, p < 0.01) and between SPBDD/Fs and the previously reported SPCDD/F concentrations (r = 0.805, p < 0.01). The estimated daily human intakes of TEQs contributed by PBDD/Fs via soil/dust ingestion and dermal exposures in e-waste recycling facilities were higher than the intakes of TEQs contributed by PCDD/Fs, calculated in our previous study. 45 refs., 2 figs., 2 tabs.
Direct photolysis of carbonyl compounds dissolved in cloud and fog~droplets
Epstein, S. A; Tapavicza, E.; Furche, F.; Nizkorodov, S. A
its ?,?-unsaturated analog acrolein, butanal and its ?,?-acid methacrolein propanal acrolein butanal crotonaldehyde 2acid methacrolein propanal acrolein butanal crotonaldehyde 2
OpenEI Community - Dimethyl Ether Market
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Dimethyl Ether Market | OpenEI Community
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Alternative Fuels Data Center: Dimethyl Ether
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWP RelatedCellulase C.Tier 2North Carolina forFuelsDiesel
Conversion of Lignocellulosic Biomass to Ethanol Butyl Acrylate
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: Theof"Wave theJuly 30, 2013 Sanyo:MarchPractices in Indian
Vehicular emission of volatile organic compounds (VOCs) from a tunnel study in Hong Kong
ethene toluene n-butane propane i-pentane i-butane propeneethene, toluene, n-butane, propane and i-pentane. These fiveVOCs emitted. The high propane and n-butane emissions were
Synthesis of octane enhancer during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 4, July 1, 1991--September 30, 1991
Marcelin, G.
The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl ether (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: Addition of isobutylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch. Addition of isobutylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst. Addition of methanol to slurry phase FT synthesis making iso-olefins.
Synthesis of octane enhancers during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 5, October 1, 1991--December 31, 1991
Marcelin, G.
The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl ether (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: Addition of isobutylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch. Addition of isobutylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst. Addition of methanol to slurry phase FT synthesis making iso-olefins.
Equilibrium thermodynamic analysis of liquid-phase ethyl tert-butylether (ETBE) synthesis
Jensen, K.L.; Datta, R. [Univ. of Iowa, Iowa City, IA (United States)
Methyl tertiary butyl ether (MTBE) is now the second largest volume organic chemical, only behind ethylene, produced in the U.S. This is remarkable since its commercial production began barely two decades ago. Although MTBE is currently the industry standard, it has been proposed that ethanol and other renewable additives make up to 30% of the oxygenate market. As a result, ethyl tertiary butyl ether (ETBE, or 2-ethyoxy 2-methyl propane), derived from renewable ethanol and isobutylene, has emerged as a promising new oxygenate. ETBE also has a somewhat lower blending Reid vapor pressure as well as a higher octane number than MTBE. This paper describes the thermodynamic equilibrium constant for the production of ETBE.
Alujain Corp., a member of the Xenel group of Saudi Arabia, is going ahead with plans to build an 800,000-m.t./year methyl tert-butyl ether (MTBE) plant. Bechtel has been appointed project manager for the plant, which will be owned by a new company, National Fuel Additives (Tahseen). Bechtel will help evaluate proposals already submitted for the lump sum turnkey job.
MTBE from butadiene-rich C/sub 4/s
Ancillotti, F.; Pescarollo, E.; Szatmari, E.; Lazar, L.
Methyl tert-butyl ether (MTBE), is made by reacting methanol with isobutylene. The preferred source of isobutylene is a steam cracker C/sub 4/ cut from which butadiene has been removed. However, moving the MTBE synthesis upstream of the butadiene extraction will improve the extraction step. The following is a review of conditions imposed on the MTBE unit's design and operation when placed in this new location.
Two US markets, or one? How the MTBE-gasoline relationship is evolving
This issue of Energy Detente features the price sensitivity of Methyl Tertiary Butyl Ether. Data is presented for US wholesale gasoline prices vs. MTBE for the 20-month period beginning in June 1994 and ending in January 1996, and the data is discussed. Also contained in this issue is the refining netback data and the fuel price/tax data for the period ending January 5, 1996.
Statoil outlines MTBE development program
Not Available
This paper reports that Norway's state oil company Den Norkse state Oljeselskap AS has outlined plans to become one of the major European producers of methyl tertiary butyl ether in the 1990s. Statoil predicts European demand for MTBE will jump to 4.5 million metric tons/year by 2000 from 2.5 million tons in 1990. Europe currently is a net importer of MTBE, with a productive capacity of 2.2 million tons/year.
Energy Efficient Refinery Process Developed with U.S. D.O.E. Support
Mings, W. J.
ENERGY EFFICIENT REFINERY PROCESS DEVELOPED WITH U.S. D.O.E. SUPPORT Walter J. Mings, P.E. EG&G Idaho, Inc. Idaho Falls, Idaho Abstract The United States Department of Energy histori cally has encouraged private efforts to develop en ergy... with potential for extensive industrial energy savings. INTRODUCTION An innovative energy saving refinery process (also called the catalytic distillation process) for pro ducing MTBE (Methyl Tertiary Butyl Ether) was devel oped by two Houston companies...
Capture isobutylene with glycol
Knifton, J.F. (Texaco Chemical's Austin Research Lab. TX (United States))
The separation of butenes present in C-4 streams (generated as a result of steam or catalytic cracking) is becoming increasingly important as the butenes find expanded applications in the production of methyl-t-butyl ether (MTBE), methyl methacrylate, butyl rubber, and linear low-density polyethylene. Available methods of separation include selective extraction with a liquid solvent (usually an acid); the use of addition reactions with suitable alcohols, acids, or water; selective polymerization and physical separation by absorbents. Three currently important separation processes for isobutylene production are an extraction route using mineral acid, the dehydration of tert-butanol, and the cracking of MTBE. As part of the research into solid acid catalysis for the generation of glycol tert-butyl monoethers, the authors have demonstrated an alternative C-4 separation process using solid inorganic acid catalysts and involving the intermediate preparation of glycol ethers. This new C-4 separation scheme could be particularly attractive to existing glycol producers who may also have a market, or internal need, for glycol monoalkyl ethers, as well as those who do not have MTBE capacity but still require pure isobutylene as a chemical intermediate or comonomer building block. The process is described.
J. Am. Chem. SOC.1988, 110, 8305-8319 8305 Hydrogenolysis of Ethane, Propane, n-Butane, and Neopentane
Goodman, Wayne
J. Am. Chem. SOC.1988, 110, 8305-8319 8305 Hydrogenolysis of Ethane, Propane, n, Pasadena, California 91125. Received February I, 1988 Abstract: The hydrogenolysisof ethane, propane, n for ethane, propane, and neopentane involvesthe cleavage of a single carbon-carbon bond, resulting
Faraday Discuss. Chem. SOC.,1989, 87, 337-344 Butane Hydrogenolysis over Single-crystal Rhodium Catalysts
Goodman, Wayne
>propane. The hydrogenolysis reaction exhibits a good fit to Arrhenius behaviour for reaction temperatures surface coverage of hydrogen. The `roll over' affects product distribution, yielding more complete
Chemical evolution of volatile organic compounds in the outflow of the Mexico City Metropolitan area
C-130 T0 T1 G1 Ethane Propane i-Butane n-Butane i-Pentane n-ppbv) Ethane Ethene Ethyne Propane Propene i-Butane n-Butanee.g. , ethane, ethene, propane, propane, methanol, ethanol,
Finding the missing stratospheric Bry: a global modeling study of CHBr3 and CH2Br2
C-130 T0 T1 G1 Ethane Propane i-Butane n-Butane i-Pentane n-ppbv) Ethane Ethene Ethyne Propane Propene i-Butane n-Butanee.g. , ethane, ethene, propane, propane, methanol, ethanol,
Extractant composition including crown ether and calixarene extractants
Meikrantz, David H. (Idaho Falls, ID); Todd, Terry A. (Aberdeen, ID); Riddle, Catherine L. (Idaho Falls, ID); Law, Jack D. (Pocalello, ID); Peterman, Dean R. (Idaho Falls, ID); Mincher, Bruce J. (Idaho Falls, ID); McGrath, Christopher A. (Blackfoot, ID); Baker, John D. (Blackfoot, ID)
An extractant composition comprising a mixed extractant solvent consisting of calix[4] arene-bis-(tert-octylbenzo)-crown-6 ("BOBCalixC6"), 4',4',(5')-di-(t-butyldicyclo-hexano)-18-crown-6 ("DtBu18C6"), and at least one modifier dissolved in a diluent. The DtBu18C6 may be present at from approximately 0.01M to approximately 0.4M, such as at from approximately 0.086 M to approximately 0.108 M. The modifier may be 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol ("Cs-7SB") and may be present at from approximately 0.01M to approximately 0.8M. In one embodiment, the mixed extractant solvent includes approximately 0.15M DtBu18C6, approximately 0.007M BOBCalixC6, and approximately 0.75M Cs-7SB modifier dissolved in an isoparaffinic hydrocarbon diluent. The extractant composition further comprises an aqueous phase. The mixed extractant solvent may be used to remove cesium and strontium from the aqueous phase.
Alternative Fuels Data Center: Dimethyl Ether (DME) as a Transportatio...
Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]
The AFDC is a resource of the U.S. Department of Energy's Clean Cities program. Contacts | Web Site Policies | U.S. Department of Energy | USA.gov Content Last Updated: 01282015...
Polybrominated Diphenyl Ethers in the Sediments of the Great Lakes.
Rockne, Karl J.
-retardants that are used in a wide range of consumer products including paints, plastics, textiles, and electronics. They are considered to be environmentally persistent due to their resistance to various degradation, and their high and have a large impact on their distribu- tion, transport, and fate. Sediment profiles from carefully
Catalytic Asymmetric Synthesis of Hydroxy Enol Ethers: Approach to a
Walsh, Patrick J.
for the generation of polypro- pionate backbone.1-7 In contrast, the asymmetric acetate aldol reaction that leads associated with acetate aldol reactions have prompted investigations into alternative methods to generate the catalytic asymmetric allylation of aldehydes followed by oxidative cleavage of the allyl group (Scheme 1, A
Direct Dimethyl Ether Polymer Electrolyte Fuel Cells for Portable Applications
. However, hydrogen suf- fers from low storage density and lack of storage, generation, and distribution at atmospheric pressure. It is typically stored as a liquid at 0.6 MPa 75 psig in standard propane tanks. DME
allene ether nazarov: Topics by E-print Network
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Administration to become the nation's energy landscape. However, the environmental impacts associated with fracking'' for shale gas Angenent, Lars T. 213 Allen County...
Copper mediated synthesis of mono-and dichlorinated diaryl ethers
Cirkva, Vladimir
): (ppm) 158.32, 156.28, 135.01, 130.45, 129.91, 123.98, 123.15, 119.40, 118.75, 116.66. GC/MS (EI, 70 e and after compound. Electron impact (EI) mass spectra (Thermo Scientific Focus DSQ) were determined (CDCl3, 75 MHz): (ppm) 157.19, 129.68, 123.15, 118.83. GC/MS (EI, 70 eV): m/z (%) 171 (13), 170 (M
archaeal isoprenoid ether: Topics by E-print Network
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Low Band Gap Polymers" Weibin Cui and Fred Wudl Macromolecules, 46 (18): 7232-7238 (2013). DOI Link "A Montarnal, Nancy D. Eisenmenger, Sung-Yu Ku, Michael L....
alternariol monomethyl ether: Topics by E-print Network
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Low Band Gap Polymers" Weibin Cui and Fred Wudl Macromolecules, 46 (18): 7232-7238 (2013). DOI Link "A Montarnal, Nancy D. Eisenmenger, Sung-Yu Ku, Michael L....
allyl glycidyl ether: Topics by E-print Network
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Low Band Gap Polymers" Weibin Cui and Fred Wudl Macromolecules, 46 (18): 7232-7238 (2013). DOI Link "A Montarnal, Nancy D. Eisenmenger, Sung-Yu Ku, Michael L....
anesthesia ether cyclopropane: Topics by E-print Network
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the alternate stepwise (carbometalation) pathway in non-polar and polar (THF, 7.85) media. These results for synthesizing cyclopropane rings has a long history dating back at...
OpenEI Community - Dimethyl Ether Market Size
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OpenEI Community - Dimethyl Ether Market Trends
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Dimethyl Ether Market Trends | OpenEI Community
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A Potential Microhydro SiteDaytonDestilaria detheDiebuOpenDimethyl
Alternative Fuels lDimethyl Ether Rheology and Materials Studies |
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NM -Alicia Moulton AboutDepartment of Energy Fuels
Boreal forest fire emissions in fresh Canadian smoke plumes: C1-C10 volatile organic compounds (VOCs), CO2, CO, NO2, NO, HCN and CH3CN
propene, acetone, benzene, propane and ?-pinene (Table 1).cyanide Acetonitrile Ethane Propane i-Butane n-Butane i-= Ethane Ethane Ethane Ethane Propane Propane Propane ARCTAS
Health concerns fuel EPA study of ETBE and TAME
Lucas, A.
Citing possible health risks associated with the use of methyl tert-butyl ether (MTBE) in winter-blend gasoline and requirements of the 1990 Clean Air Act (CAA), EPA has called for testing the health effects of ethyl tert-butyl ether (EBTE) and tert-amyl methyl ether (TAME). The program calls for toxicity testing to develop data on the health effects of ETBE and TAME. EPA may require chemical manufacturers and processors to provide the data. A public meeting will be held this week to begin working on an agreement. EPA says most of the data should be collected in 1995 and expects the program to cost approximately $3 million. In December, EPA floated a proposal to require 30% of the oxygenates used in the reformulated gasoline program to come from renewable sources such as ETBE and ethanol. Although EPA found no serious health risks associated with MTBE, questions remain, which is why EPA says it will test the use of ETBE and TAME. William Piel, business manager for oxygenated fuels at Arco Chemical (Newtown Square, PA), says testing is {open_quotes}just a formality.{close_quotes} There should be no difference in results among MTBE, ETBE, or TAME, he says. But ETBE and TAME have much lower volatility than MTBE, which would mean significantly less exposure to these oxygenates, Piel says. Arco is the biggest producer of MTBE but also has capability to make ETBE.
Texas plant will use new process to coproduce propylene oxide, MTBE
Rhodes, A.K.
Texaco Chemical Co. is building a $400 + million facility to produce 1.2 billion lb/year (14,000 b/d) methyl tertiary butyl ether (MTBE) and 400 million lb/year (about 500 metric tons/day) propylene oxide (PO). The facility-under construction at Port Neches, Tex.-will utilize a newly developed Texaco process that coproduces the two chemicals. The process produces propylene oxide and tertiary butyl alcohol (TBA) from the reaction of isobutane with oxygen in one step, then in a second step with propylene. The TBA is then reacted with methanol in a one-step process that synthesizes MTBE. The paper describes the Port Neches facilities, construction schedule, feedstocks, product uses, and auxiliary equipment.
Splitting a C-O bond in dialkylethers with bis(1,2,4-tri-t-butylcyclopentadienyl) cerium-hydride does not occur by a sigma-bond metathesis pathway: a combined experimental and DFT computational study
Werkema, Evan; Yahia, Ahmed; Maron, Laurent; Eisenstein, Odile; Andersen, Richard
Addition of diethylether to [1,2,4(Me3C)3C5H2]2CeH, abbreviated Cp'2CeH, gives Cp'2CeOEt and ethane. Similarly, di-n-propyl- or di-n-butylether gives Cp'2Ce(O-n-Pr) and propane or Cp'2Ce(O-n-Bu) and butane, respectively. Using Cp'2CeD, the propane and butane contain deuterium predominantly in their methyl groups. Mechanisms, formulated on the basis of DFT computational studies, show that the reactions begin by an alpha or beta-CH activation with comparable activation barriers but only the beta-CH activation intermediate evolves into the alkoxide product and an olefin. The olefin then inserts into the Ce-H bond forming the alkyl derivative, Cp'2CeR, that eliminates alkane. The alpha-CH activation intermediate is in equilibrium with the starting reagents, Cp'2CeH and the ether, which accounts for the deuterium label in the methyl groups of the alkane. The one-step sigma-bond metathesis mechanism has a much higher activation barrier than either of the two-step mechanisms.
Catalytic conversion of light alkanes - phase V. Topical report, February 1993--October 1994
We have made excellent progress toward a practical route from field butanes to MTBE, the oxygenate of choice for high-octane, clean-burning, environmentally acceptable reformulated gasoline. We have evaluated two proprietary process possibilities with a potential commercial partner and have conducted a joint catalyst evaluation program. The first of the two potential processes considered during the past quarter utilizes a two-step route from isobutane to tert-butyl alcohol, TBA. Not only is TBA an intermediate for MTBE production but is equally applicable for ETBE-an oxygenate which utilizes renewable ethanol in its` manufacture. In the two-step process, isobutane is oxidized in a non-catalytic reaction to a roughly equal mixture of TBA and tert-butyl hydroperoxide. TBHP, eq. 1. We have developed an inexpensive new catalyst system based on an electron-deficient macrocyclic metal complex that selectively converts TBHP to TBA, eq. 2, and meets or exceeds all of the process criteria that we have set.
Saponification rates of isomeric butyl esters in aqueous 1,4-dioxane
Ruhnke, Edward Vincent
. Jensen, G. M. Watson and J. B. Beckham, Anal. Chem., 23, 1711-8(1951). (21). F. Daniels, J. H. Mathews and J, W. Williams, "Experimental Physical Chemistry," 3rd. ed., McGraw-Hill Book Co., Inc., New York, N. Y., 19*4-1, p. 167. (22). S. Glasstone...
Safe conditions for contacting nitric acid or nitrates with tri-n-butyl phosphate (TBP)
Hyder, M.L
In response to a request from DOE-SR, the current state of knowledge of the reactions between TBP and aqueous nitrate solutions is critically reviewed, and recommendations are made for the safe operation of SRS separations equipment in which this combination of chemicals may be present. The existing limits for evaporation are validated. Guidelines are presented for cases in which general limits do not apply. The rate of reaction between nitric acid and TBP appears to be controlled by the rate of TBP hydrolysis. The hydrolysis reaction produces dibutyl phosphate and n-butanol. The hydrolysis rate is a strong function of temperature, and becomes very fast at temperatures in the range 130{degrees} to 150{degrees}C. The resulting n-butanol is volatile at high temperatures, boiling at 117.5{degrees}C, but is also subject to exothermic oxidation by nitric acid or nitrates. If oxidation occurs before the n-butanol evaporates, the heat of oxidation may exceed local cooling by convection. The resulting heating will further accelerate the reaction, leading to an energetic runaway and possibly (in confined systems) an explosion. Extensive experiments and practice have shown that in a well-mixed and well-vented aqueous system such as an evaporator, at moderate acidities and temperatures below 130{degrees}C, the heat of reaction is adequately removed by vaporization of steam. In general, the heating will be so slow that natural processes provide adequate cooling at temperatures below 80{degrees}C. Above this temperature, care should be taken to ensure that adequate cooling is available for the amount of TBP that may be present. Experiments suggest that in well-ventilated systems n-butanol evaporation and convective cooling are sufficient to control the reaction at temperatures up to 120{degrees}C.
The K-band microwave spectra of t-butyl halides
Crook, George Hardy
result of centrifugal distortion of the mole? cule, and (c) a group of lines from either the hindered internal rotation of the CH^ groups or torsional vibration along the C-CH-j bonds, or both. In an attempt to determine the sources of the indi... absorption lines in the microwave re? gion were reported by Cleeton and Williams (2) in 1934* No more papers on this subject appeared in the literature until 1946. Since this latter date, however, some 400 papers relating to miorowave absorption spectra...
acetone-butyl alcohol fermentation: Topics by E-print Network
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and Dissertations Summary: ??ENGLISH ABSTRACT: Alcoholic fermentation, and especially wine fermentation, is one of the most ancient microbiological processes utilized by man....
aluminum triso-ethylphosphonate butylate: Topics by E-print Network
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Repository Summary: Damping and Dynamic Modulus Measurements in Alumina and Tungsten Fibre-Reinforced Aluminium Composites. the damping capacity of aluminum tungsten fiber...
acid t-butyl ester: Topics by E-print Network
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stable thermodynamically and hydration free energies obtained Yu, Fangqun 189 ANTIBODY PURIFICATION USING CAPRYLIC ACID In mildly acidic conditions, the addition of short-chain...
Batch polymerization of styrene initiated by n-butyl lithium in a cyclohexane solvent
Landon, Thomas Rodman
the effect of autocatalytic initiation. The propagation rate constant is assumed to be independent of chain length. In order to solve equation (49), one can use equation (46) and obtain nM(P . ? P . ) dt j i I (SO) where kp / p T If one assumes 2K..., they were then dried overnight in a vacuum oven at 200 to 220'C and 30 inches Hg. vacuum. Before removing the bottjes from the oven, the oven was pressured to at- mospheric pressure with prepurified nitrogen. As quickly as possible, after the bottles...
Pentan isomers compound flame front structure
Mansurov, Z.A.; Mironenko, A.W.; Bodikov, D.U.; Rachmetkaliev, K.N. [Kazakh Al-Farabi State National Univ., Almaty (Kazakhstan)
The fuels (hexane, pentane, diethyl ether) and conditions investigated in this study are relevant to engine knock in spark- ignition engines. A review is provided of the field of low temperature hydrocarbon oxidation. Studies were made of radical and stable intermediate distribution in the front of cool flames: Maximum concentrations of H atoms and peroxy radicals were observed in the luminous zone of the cool flame front. Peroxy radicals appear before the luminous zone at 430 K due to diffusion. H atoms were found in cool flames of butane and hexane. H atoms diffuses from the luminous zone to the side of the fresh mixture, and they penetrate into the fresh mixture to a small depth. Extension of action sphear of peroxy radicals in the fresh mixture is much greater than that of H atoms due to their small activity and high concentrations.
Health studies indicate MTBE is safe gasoline additive
Anderson, E.V.
Implementation of the oxygenated fuels program by EPA in 39 metropolitan areas, including Fairbanks and Anchorage, Alaska, in the winter of 1992, encountered some unexpected difficulties. Complaints of headaches, dizziness, nausea, and irritated eyes started in Fairbanks, jumped to Anchorage, and popped up in various locations in the lower 48 states. The suspected culprit behind these complaints was the main additive for oxygenation of gasoline is methyl tert-butyl ether (MTBE). A test program, hastily organized in response to these complaints, has indicated that MTBE is a safe gasoline additive. However, official certification of the safety of MTBE is still awaited.
Veba in MTBE project, cutting aromatics
Young, I.; Roberts, M.
The new owners of the refinery and petrochemical complex at Schwedt in eastern Germany-RWE-DEA (Hamburg), Veba Oel (Gelsenkirchen), Agip (Rome), Total (Paris), and Elf-Aquitaine (Paris)-plan to build a 60,000-m.t./year methyl tert-butyl ether (MTBE) plant at the site for 1994-1995 completion. The MTBE project forms part of the consortium`s announced DM1.5-billion ($500 million) investment program for the complex that aims to raise refinery throughput from 8 million m.t./year to 12 million m.t./year by 1994 and hike production of naphtha and benzene.
Evaluation and Optimization of MTBE Biodegradation in Aquifers, Final Report
Legler, T; Balser, L; Koester, C; Wilson, W
This study was focused on meeting the following objectives concerning the process of methyl tertiary butyl ether (MTBE) biodegradation, with the goal of optimizing this process in situ: 1. Assess whether intrinsic bioattenuation of MTBE is feasible under aerobic conditions across several contaminated sites. 2. Determine the effect of co-contaminants, specifically water-soluble gasoline components (most notably benzene, toluene, ethylbenzene and xylenes [BTEX]) on MTBE biodegradation. 3. Determine whether microbial and/or chemical factors contribute to different MTBE degradative activities. 4. Isolate and characterize MTBE-degrading microorganisms from sediments in which MTBE biodegradation was observed.
Austrian refiner benefits from advanced control
Richard, L.A.; Spencer, M. [Setpoint Inc., Houston, TX (United States); Schuster, R.; Tuppinger, D.M.; Wilmsen, W.F. [OeMV-AG Energy, Schwechat (Austria)
OeMV-AG Energy implemented advanced process controls on 27 units at its refinery in Schwechat, Austria. A variety of controls were implemented on the butadiene and methyl tertiary butyl ether (MTBE) units in January 1993. After more than 1 year of operation, the butadiene/MTBE project has shown a number of benefits, including reduced energy consumption and increased capacity in both units. The paper discusses the process, advanced control, the simple model predictive controller, control objectives, the butadiene unit, the MTBE unit, and benefits of the advanced controllers.
Petrochem industry expands North American MTBE capacity
Not Available
This paper reports that petrochemical manufacturers continue to increase methyl tertiary butyl ether (MTBE) capacity in North America. The action reflects refiners' reformulation of gasoline to help reduce auto emissions. Demand for gasoline blending oxygenates such as MTBE is expected to increase as U.S. refiners reconfigure processing trains to produce fuels meeting requirements of the Clean Air Act amendments of 1990. Recent progress includes plans to build an MTBE plant in Mexico and start-ups of plants on the U.S. Gulf Coast and in Canada.
MTBE growth limited despite lead phasedown in gasoline
Storck, W.
This month's legislated reduction of the allowable amount of lead additives in gasoline will increase demand strongly for methyl-tert-butyl ether (MTBE) as an octane enhancer, but the economics of the refinery business and the likelihood of rapidly increasing high-octane gasoline imports probably will limit the size of the business in coming years. MTBE will be used to fill the octane gap now, but economics and imports of gasoline later on could hold down demand. The limited growth in sales of MTBE is discussed.
A near infrared regression model for octane measurements in gasolines which contain MTBE
Maggard, S.M. (Ashland Petroleum Co., KY (USA))
Near infrared (NIR) spectroscopy has emerged as a superior technique for the on-line determination of octane during the blending of gasoline. This results from the numerous advantages that NIR spectroscopy has over conventional on-line instrumentation. Methyl t-butyl ether (MTBE) is currently the oxygenated blending component of choice. MTBE is advantageous because it has a high blending octane, a low Reid vapor pressure, is relatively cheap, and does not form peroxides (1). The goal of this project was to develop a NIR regression model that could be used to predict pump octanes regardless of whether they contained MTBE.
MTBE: Capacity boosts on hold amid demand concerns
Uncertainty reigns in the methyl tert-butyl ether (MTBE) market. {open_quotes}We have no choice but to put our expansion plans on the back burner,{close_quotes} says one producer. {open_quotes}Because of government actions, there are no MTBE plants being built or expanded.{close_quotes} Spot MTBE prices have risen ti 82 cts- 83 cts/gal from 76 cts-78 cts/gal earlier this month as the demand for octane enhancement increases for the summer driving season. Some observers say EPA may relax different oxygen requirements for gasoline in different seasons. That would simplify production and supply for MTBE makers.
Methanex considers methanol, MTBE in Qatar
CW has learned that Methanex Corp. is considering entering one of two methanol and methyl tert-butyl ether (MTBE) projects in Qatar. Executive v.p. Michael Wilson says that part of the company`s New Zealand plant could be moved to a site in Qatar, which would lower capital costs for the possible project by $75 million-$100 million. Both Qatar General Petroleum Corp. and Qatar Fuel Additives are developing methanol and MTBE projects at Umm Said, Qatar. Methanex says its goal is to ensure low-cost feedstocks.
Al-Jarallah, A.M.; Lee, A.K.K.
Methyl Tertiary Butyl Ether (MTBE) is produced industrially by catalytic reaction between methanol and isobutene. The catalyst that is widely used is an acidic ion exchange resin. This article explores design and economics when sulfuric acid is the catalyst. The profitability of MTBE production depends mainly on the cost of butenes and methhanol. Thus, the example shows MTBE made with a catalyst of sulfuric acid was profitable at a Saudi Arabian location, even though it was not profitable at a U.S. Gulf Coast location.
MTBE: Wild card in groundwater cleanup
Koenigsberg, S. [Regenesis Bioremediation Products, San Juan Capistrano, CA (United States)
Subsurface releases of the gasoline oxygenate, methyl tertiary butyl ether (MTBE) seriously compromise the remediation and closure of properties that have ground water contaminated with BTEX and other conventional fuel hydrocarbon components. Although a manageable protocal for BTEX remediation is being set up, the MTBE problem continues to be difficult. This article discusses a new magnesium peroxide compound which could be part of the solution. Covered topics include oxygen release compound (ORC) enhance bioremediation and the role of oxygen and ORC in MTBE remediation. 1 fig.
Total to withdraw from Qatar methanol - MTBE?
Total is rumored to be withdrawing from the $700-million methanol and methyl tert-butyl ether (MTBE) Qatar Fuel Additives Co., (Qafac) project. The French company has a 12.5% stake in the project. Similar equity is held by three other foreign investors: Canada`s International Octane, Taiwan`s Chinese Petroleum Corp., and Lee Change Yung Chemical Industrial Corp. Total is said to want Qafac to concentrate on methanol only. The project involves plant unit sizes of 610,000 m.t./year of MTBE and 825,000 m.t./year of methanol. Total declines to comment.
MTBE, Oxygenates, and Motor Gasoline (Released in the STEO October 1999)
Reports and Publications (EIA)
The blending of methyl tertiary butyl ether (MTBE) into motor gasoline has increased dramatically since it was first produced 20 years ago. MTBE usage grew in the early 1980's in response to octane demand resulting initially from the phaseout of lead from gasoline and later from rising demand for premium gasoline. The oxygenated gasoline program stimulated an increase in MTBE production between 1990 and 1994. MTBE demand increased from 83,000 in 1990 to 161,000 barrels per day in 1994. The reformulated gasoline (RFG) program provided a further boost to oxygenate blending. The MTBE contained in motor gasoline increased to 269,000 barrels per day by 1997.
Oxygenate Supply/Demand Balances in the Short-Term Integrated Forecasting Model (Released in the STEO March 1998)
Reports and Publications (EIA)
The blending of oxygenates, such as fuel ethanol and methyl tertiary butyl ether (MTBE), into motor gasoline has increased dramatically in the last few years because of the oxygenated and reformulated gasoline programs. Because of the significant role oxygenates now have in petroleum product markets, the Short-Term Integrated Forecasting System (STIFS) was revised to include supply and demand balances for fuel ethanol and MTBE. The STIFS model is used for producing forecasts in the Short-Term Energy Outlook. A review of the historical data sources and forecasting methodology for oxygenate production, imports, inventories, and demand is presented in this report.
Alternate fuels for general-aviation aircraft with spark-ignition engines. Final report
Ferrara, A.M.
This report describes the results of a study into the behavior of several alternate fuels that are under consideration for use in general aviation aircraft engines. The study consisted of a literature search and engine tests using a dynamometer. The literature search identified material compatibility problems and possible solutions to these problems. For the engine tests, a number of gasoline/alcohol blends were prepared using both ethanol and methanol in varying concentrations and the vapor-lock behavior was identified. Neat alcohols and methyl-tertiary-butyl ether were also used in the engine, and special operational conditions and problems were identified.
California's Move Toward E10 (released in AEO2009)
Reports and Publications (EIA)
In Annual Energy Outlook 2009, (AEO) E10–a gasoline blend containing 10% ethanol–is assumed to be the maximum ethanol blend allowed in California erformulated gasoline (RFG), as opposed to the 5.7% blend assumed in earlier AEOs. The 5.7% blend had reflected decisions made when California decided to phase out use of the additive methyl tertiary butyl ether in its RFG program in 2003, opting instead to use ethanol in the minimum amount that would meet the requirement for 2.0% oxygen content under the Clean Air Act provisions in effect at that time.
Catalytic distillation process
Smith, Jr., Lawrence A. (Bellaire, TX)
A method for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C.sub.4 feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.
Catalytic distillation process
Smith, L.A. Jr.
A method is described for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C[sub 4] feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.
Method for controlled oligomerization/etherification of propylene
Keyworth, O.A.
This patent describes a process for the reaction of propylene in a hydrocarbon feed stream. The process consists of contacting the feed stream containing propylene and at least 5 weight % isobutene based on the feed stream in liquid phase with an acidic cation exchange resin at temperatures in the range of 80/sup 0/-130/sup 0/C at LHSV in the range of 2 to 5 in the presence of methanol. This produces a product stream essentially comprising C/sub 6/ to C/sub 8/ mono olefins, methyl isopropyl ether, methyl tertiary butyl ether and unreacted material. The amount of methanol determined by a residual of the methanol in the product stream is in the range of 0.03 to 0.9 wt. % based on the product stream.
EPA`s proposed renewable oxygenate requirement (ROR): Pros and cons
Czeskleba, H.M. [Ashland Petroleum Co., KY (United States)
In December 1993, the US Environmental Protection Agency (EPA) released its final rule that sets for the details for requirements to sell reformulated gasoline (RFG) in certain ozone non-attainment areas. At the same time, EPA also issued a proposed rule to require that 30% of the oxygen required in RFG be based on a renewable oxygenate. Renewables include ethanol and its ether derivatives such as ethyl tertiary butyl ether (ETBE). The RFG rule is a final rule, while the Renewable Oxygenate Requirement (ROR) rule is a proposed rule yet to be finalized and subject to revision. Included in this paper are brief reviews of Ashland petroleum Company`s ethanol usage, oxygenated fuel and reformulated gasoline blending economics, and some comments on the EPA proposed renewable oxygenate requirement.
4912r 2010 American Chemical Society pubs.acs.org/EF Energy Fuels 2010, 24, 49124918 : DOI:10.1021/ef1007962
GĂĽlder, Ă?mer L.
fractions of binary mixtures of butane isomers, ethylene-butane isomers, and propane- butane isomers were components under the same flame conditions. Binary mixtures of propane and butane isomers, however, did associated with potential interactions between pyrolysis pro- ducts of the hydrocarbons in the mixture
EFFECT OF FUEL TYPE ON FLAME IGNITION BY TRANSIENT PLASMA Jianbang Liu1,2
ABSTRACT Rise and delay times of mixtures of methane, propane, n-butane, iso-butane and iso- octane mixed performance of various fuels including methane, propane, iso-butane, n-butane and iso-octane mixed with air with air ignited by transient plasma discharge were investigated and compared with spark discharge ignition
Coal-transformation chemistry. Fourth quarterly progress report
Stock, Leon M.; Blain, D. A.; Handy, C. I.; Heimann, P.; Huang, C. B.; King, H. -H.; Landschulz, W.; Willis, R. S.
Pyrene, perylene, anthracene, 9,10-diphenylanthracene, naphthalene and biphenyl have been employed as electron transfer agents in the reduction of Illinois No. 6 coal with potassium in tetrahydrofuran. These electron transfer agents are about equally effective for the reduction of this coal at short reaction times (3 hours). We conclude that the anions of biphenyl and naphthalene achieve a greater degree of electron transfer to the coal molecules and that the use of these anions enhances the fragmentation reactions of the coal. Illinois No. 6 bituminous coal and Colorado subbituminous coal were reacted with potassium dissolved in a mixture of monoglyme and triglyme at -50/sup 0/C. The reduction reaction proceeded via solvated electrons rather than by an electron transfer reaction. The coals were then alkylated with methyl iodide and their solubilities in tetrahydrofuran were determined. The Illinois coal reductively alkylated via solvated electrons was considerably less soluble in tetrahydrofuran than the same coal reductively alkylated with potassium and naphthalene in tetrahydrofuran. A sample of Illinois No. 6 coal which had been reductively butylated with n-butyl-1-/sup 13/C iodide was hydrolyzed. Carbon nmr spectroscopy of the hydrolyzed coal revealed that the resonances previously assigned either to the presence of n-butyl carboxylates or to n-butyl tertiary ethers were removed. This observation provides definite evidence that only carboxylates were present in the original alkylated product. Selective alkylation of the acidic hydroxyl groups in Illinois No. 6 coal was carried out using tetrabutylammonium hydroxide as a phase transfer catalyst and iodomethane or 1-iodobutane as alkylating agent as described by Liotta. The tetrahydrofuran solubility of the product was significantly improved in a reaction where reductively butylated coal was subsequently coal was subsequently methylated using Liotta's procedure.
Arco chimie focuses on PA at FOS
Jackson, D.
Arco Chimie France (Fos-sur-Mer), at a recent meeting at its southern France manufacturing site, emphasized that future strategy is strongly focused on its propylene oxide (PO) and derivatives activities. The F2.5 billion ($466 million)-Fe billion/year operation manufactures 200,000 m.t./year of PO, about 70% for captive use and the balance for the merchant market; 550,000 m.t./year of methyl tert butyl ether (MTBE); 97,000 m.t./year of polyols; and 70,000 m.t./year of propylene glycols. There has been talk of Arco modifying its Fos MTBE plant to make it flexible for ethyl tert-butyl ether (ETBE) output; the parent company already operates an MTBE/ETBE pilot unit at Corpus Christi, TX. But Arco Chimie notes there is insufficient bioethanol feedstock availability to convert all production to ETBE. The company would also require investment in new storage capacity for ethanol and ETBE. However, France's biofuels program is not yet clearly defined, and it is politically sensitive because it depends heavily on government subsidies offered to farmers. That, says Arco, makes it impossible to have an accurate idea of how much ethanol will be available.
Phase equilibrium measurements on twelve binary mixtures
Giles, N.F. [Wiltec Research Co., Inc., Provo, UT (United States)] [Wiltec Research Co., Inc., Provo, UT (United States); Wilson, H.L.; Wilding, W.V. [Brigham Young Univ., Provo, UT (United States). Chemical Engineering Dept.] [Brigham Young Univ., Provo, UT (United States). Chemical Engineering Dept.
Phase equilibrium measurements have been performed on twelve binary mixtures. The PTx method was used to obtain vapor-liquid equilibrium data for the following binary systems at two temperatures each: ethanethiol + propylene; nitrobenzene + methanol; pyridine + ethyl acetate; octane + tert-amyl methyl ether; diisopropyl ether + butane; 1,3-dichloro-2-propanol + epichlorohydrin; 2,3-dichloro-1-propanol + epichlorohydrin; 2,3-epoxy-1-propanol + epichlorohydrin; 3-chloro-1,2-propanediol + epichlorohydrin; methanol + hydrogen cyanide. For these systems, equilibrium vapor and liquid phase compositions were derived from the PTx data using the Soave equation of state to represent the vapor phase and the Wilson, NRTL, or Redlich-Kister activity coefficient model to represent the liquid phase. The infinite dilution activity coefficient of methylamine in N-methyl-2-pyrrolidone was determined at three temperatures by performing PTx measurements on the N-methyl-2-pyrrolidone was determined at three temperatures by performing PTx measurements on the N-methyl-2-pyrrolidone-rich half of the binary. Liquid-liquid equilibrium studies were made on the triethylene glycol + 1-pentene system at two temperatures by directly analyzing samples taken from each liquid phase.
Coal anion structure and chemistry of coal alkylation. Final report, March 1, 1979-February 29, 1980
Stock, L.M.
In accord with Task 1, some ether cleavage reactions were carried out in two different media - potassium/naphthalene/tetrahydrofuran and potassium/ ammonia - so that the merits and demerits of the two methods could be compared. Preliminary results suggest that both systems yield the same products, and that the ammonia medium is more convenient to work with, because of the absence of by-products such as reduced naphthalenes and tetralin. Dialkyl ethers were found to be least reactive compounds while the benzyl and phenyl ethers were found to be most reactive, as would be expected. The reductive alkylation of coal was carried out in ammonia at 25/sup 0/C. The tetrahydrofuran solubility of the reaction product was surprisingly low. We have obtained additional /sup 13/C)/sup 1/H) nmr data for tetrahydrofuran-soluble butylated coal and some model compounds; obtained additional Styragel(R) chromatography data of tetrahydrofuran-soluble coal labelled with 98%-enriched butyl-1,1-d/sub 2/ iodide; and obtained /sup 2/D nmr spectra of all the deuterium-labelled, tetrahydrofuran-soluble coal products. In accord with Task 4, we have undertaken a review of the information now available concerning the nature of Illinois No. 6 coal. Also, the effects of organic additives on the exchange reactions between tetralin-d/sub 12/ and diphenyl-methane and on the thermal cleavage reactions of several model compounds in tetralin were investigated to probe the relationship between structure and reactivity. The exchange reaction can be accelerated by coal, asphaltene-preasphaltene fractions derived from coal, compounds with labile bonds, or compounds which can be reduced readily. The pyridine-insoluble coal product, acids, and bases are inactive toward the exchange reaction.
Viscoelastic Properties and Phase Behavior of 12-tert-Butyl Ester Dendrimer/Poly(methyl methacrylate) Blends
Harmon, Julie P.
with bis- phenol A polycarbonate (PC), resulting in an in- crease in free volume with increasing dendrimer hyperbranched polyester/bisphenol A PC blends with respect to pure PC. Studies were conducted by Carr et al.24
An experimental system for the n-butyl-lithium initiated polymerization of styrene in a multi-sampled batch reactor
Cox, James Harvey
temperature gradients and thereby causing concentration gradients due to increased reaction rates. No method has yet been reported for monitoring the internal temperature of such a soft-drink bottle reactor, or of providing any kind of dy- namic... and Bywater [I] showed that the initial rate of heat generation by the polymerization reac- tion would be so high that the thermal resistance of the reactor bowl would prevent isothermal operations. By using the manufacturer's stainless steel internal...
An experimental system for the n-butyl-lithium initiated polymerization of styrene in a multi-sampled batch reactor
Cox, James Harvey
-hydrogen interconversions in- stead of the desired cleavage reaction. The sulfur-sulfur bond is a chromophore that absorbs ultraviolet light in the 255 nm region with a relatively low molar absorption (z = 400). This is suffi- max ciently large for the detection...- cally there are two broad divisions of experimental methods; the ultra-high purity, evacuated glass systems and the lower purity, more rugged, bench-scale systems. One analytical method, the spectrophotometric method, as used by Worsfold and Bywater...
Characterization of photochemical pollution at different elevations in mountainous areas in Hong Kong
and (b) i-butane vs. propane at TMS and TW. Fig. 4. Theand (b) i-butane vs. propane at TMS and TW. et al. , 2001;higher ratios of ethyne/propane and benzene/propane were
Incompatible Chemicals The following list is to be used only as a general guideline. Please refer to your Material Safety
Slatton, Clint
, butane, methane, propane(or other petroleum gases), hydrogen, sodium carbide, benzene, finely divided other chemicals Hydrocarbons (such as butane, propane, benzene) Fluorine, chlorine, bromine, chromic) Tellurides Reducing Agents #12;CHEMICAL STORAGE GUIDELINES STORE MATERIALS OUTLINED BY BOXES SEPARATELY
Cinabro, David
. He considered two coolants: Butane and R134a (freon replacement used in auto air conditioners). About
Guidance Document Peroxide-FormingChemicals
months. Acrylic acid Tetrafluoroethylene Acrylonitrile Vinyl acetate 1,3-Butadiene Vinyl acetylene months. Acetal Diethylene glycol dimethyl ether (diglyme) Isopropyl alcohol Acetaldehyde Diethyl ether Isopropyl propyl ether Acrylamide Diethyl fumatate Isopropyl vinyl ether Allyl ethyl ether Diethylketene 2
Molecular Properties of the "Ideal" Inhaled Anesthetic: Studies of Fluorinated Methanes, Ethanes, Propanes,
Hudlicky, Tomas
, Propanes, and Butanes E. 1Eger, 11, MD*, J. Liu, MD*, D. D. Koblin, PhD, MDt, M. J. Laster, DVM*, S. Taheri unfluorinated, partially fluorinated, and perfluorinated methanes, ethanes, propanes, and butanes to define fluorinated methanes, ethanes, propanes, and butanes, also obtaining limited data on longer- chained alkanes
Base-Mediated Cascade Rearrangements of Aryl-Substituted Diallyl Ethers
Reid, Jolene P.; McAdam, Catherine A.; Johnston, Adam J. S.; Grayson, Matthew N.; Goodman, Jonathan M.; Cook, Matthew J.
? 7.26 ppm and 77.2 ppm respectively. Infrared spectra were recorded as a thin film on KBr discs. High- resolution mass spectra were obtained on mass spectrometers using electrospray ionization (ESI) or electron impact ionization at 70 eV and TOF... alcohol (1 equiv.) in a dry, argon purged 10 mL round-bottomed flask at room temperature. The flask was fitted with a condenser and heated to 60 oC and allowed to stir overnight. The reaction mixture slowly turned deep brown after addition of the KHMDS...
A mechanistic and experimental study on the diethyl ether oxidation S. Di Tommaso1-2
Boyer, Edmond
-00976232,version1-9Apr2014 Author manuscript, published in "AIChE Spring Meeting 2012 & 8. Global Congress] and theoretically [7], since it has a relevant role, due to its good ignition properties, in the domain of biofuels
Measurements of flatflame velocities of diethyl ether in air Fiona Gillespiea,b
Boyer, Edmond
biofuels are important in today's world due to a decline in oil and fossil fuels and an increase in CO2
Winfree, Erik
with nickel precursors was studied. A series of nickel(0) complexes containing nickel-arene interactions.1).1a,1b Quenching of the lithium species with an electrophilic species leads to the functionalization
Synthesis of the C29-C37 Bicyclic Ether Core of (+)-Sorangicin A
's asymmetric allylation protocol (>95:5 dr).7 Diol 11 was protected as its p-methoxyphenyl acetal 12 would effect hydrolysis of the acetal to form diol 3 as well as catalyze the opening of the epoxide metathesis reaction with ethyl acrylate (Table 1). The cyclic acetal was chosen as the diol protecting group
The potential for alcohols and related ethers to displace conventional gasoline components
Hadder, G.R. [Oak Ridge National Lab., TN (United States); McNutt, B.D. [USDOE, Washington, DC (United States)
The United States Department of Energy is required by law to determine the feasibility of producing sufficient replacement fuels to replace 30 percent of the projected United States consumption of motor fuels by light duty vehicles in the year 2010. A replacement fuel is a non-petroleum portion of gasoline, including alcohols, natural gas and certain other components. A linear program has been used to study refinery impacts for production of ``low petroleum`` gasolines, which contain replacement fuels. The analysis suggests that high oxygenation is the key to meeting the replacement fuel target, and major contributors to cost increase can include investment in processes to produce olefins for etherification with alcohols. High oxygenation can increase the costs of control of vapor pressure, distillation properties, and pollutant emissions of gasolines. Year-round low petroleum gasoline with near-30 percent non-petroleum might be produced with cost increases of 23 to 37 cents per gallon, with substantial decreases in greenhouse gas emissions in some cases. Cost estimates are sensitive to assumptions about extrapolation of a national model for pollutant emissions, availability of raw materials and other issues. Reduction in crude oil use, a major objective of the low petroleum gasoline program, is 10 to 17 percent in the analysis.
Cu-Catalyzed Arylation of Phenols: Synthesis of Sterically Hindered and Heteroaryl Diaryl Ethers
Maiti, Debabrata
Cu-catalyzed O-arylation of phenols with aryl iodides and bromides can be performed under mild condition in DMSO/K3PO4 with use of picolinic acid as the ligand for copper. This method tolerates a variety of functional ...
The processing of alcohols, hydrocarbons and ethers to produce hydrogen for a PEMFC for transportation applications
Dams, R.A.J.; Hayter, P.R.; Moore, S.C. [Wellman CJB Limited, Portsmouth (United Kingdom)
Wellman CJB Limited is involved in a number of projects to develop fuel processors to provide a hydrogen-rich fuel in Proton Exchange Membrane Fuel Cells (PEMFC) systems for transportation applications. This work started in 1990 which resulted in the demonstration of 10kW PEMFC system incorporating a methanol reformer and catalytic gas clean-up system. Current projects include: The development of a compact fast response methanol reformer and gas clean-up system for a motor vehicle; Reforming of infrastructure fuels including gasoline, diesel, reformulated fuel gas and LPG to produce a hydrogen rich gas for PEMFC; Investigating the potential of dimethylether (DME) as source of hydrogen rich gas for PEMFCs; The use of thin film palladium diffusers to produce a pure hydrogen stream from the hydrogen rich gas from a reformer; and Processing of naval logistic fuels to produce a hydrogen rich gas stream for PEMFC power system to replace diesel generators in surface ships. This paper outlines the background to these projects and reports their current status.
Cesium and strontium extraction using a mixed extractant solvent including crown ether and calixarene extractants
Meikrantz, David H. (Idaho Falls, ID); Todd, Terry A. (Aberdeen, ID); Riddle, Catherine L. (Idaho Falls, ID); Law, Jack D. (Pocatello, ID); Peterman, Dean R. (Idaho Falls, ID); Mincher, Bruce J. (Idaho Falls, ID); McGrath, Christopher A. (Blackfoot, ID); Baker, John D. (Blackfoot, ID)
A mixed extractant solvent including calix[4]arene-bis-(tert-octylbenzo)-crown-6 ("BOBCalixC6"), 4',4',(5')-di-(t-butyldicyclo-hexano)-18-crown-6 ("DtBu18C6"), and at least one modifier dissolved in a diluent. The mixed extractant solvent may be used to remove cesium and strontium from an acidic solution. The DtBu18C6 may be present from approximately 0.01 M to approximately 0.4M, such as from approximately 0.086 M to approximately 0.108 M. The modifier may be 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol ("Cs-7SB") and may be present from approximately 0.01M to approximately 0.8M. In one embodiment, the mixed extractant solvent includes approximately 0.15M DtBu18C6, approximately 0.007M BOBCalixC6, and approximately 0.75M Cs-7SB modifier dissolved in an isoparaffinic hydrocarbon diluent. The mixed extractant solvent may form an organic phase in an extraction system that also includes an aqueous phase. Methods of extracting cesium and strontium as well as strontium alone are also disclosed.
a-fluorinated ethers thioethers: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Low Band Gap Polymers" Weibin Cui and Fred Wudl Macromolecules, 46 (18): 7232-7238 (2013). DOI Link "A Montarnal, Nancy D. Eisenmenger, Sung-Yu Ku, Michael L....
MC-CAM Publications "Allyl Glycidyl Ether-Based Polymer Electrolytes for Room Temperature Lithium Batteries"
Bigelow, Stephen
ÂAcceptor Low Band Gap Polymers" Weibin Cui and Fred Wudl Macromolecules, 46 (18): 7232-7238 (2013). DOI Link "A
anhydride-methyl vinyl ether: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Low Band Gap Polymers" Weibin Cui and Fred Wudl Macromolecules, 46 (18): 7232-7238 (2013). DOI Link "A Montarnal, Nancy D. Eisenmenger, Sung-Yu Ku, Michael L....
acid-methyl vinyl ether: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Low Band Gap Polymers" Weibin Cui and Fred Wudl Macromolecules, 46 (18): 7232-7238 (2013). DOI Link "A Montarnal, Nancy D. Eisenmenger, Sung-Yu Ku, Michael L....
Polybrominated diphenyl ethers in relation to autism and developmental delay: A case-control study
212:109-134. 5. Rose M, Bennett DH, Bergman A, Fangstrom B,Robin Hansen 4 , Deborah H Bennett 1 Abstract Background:
Synthesis and Modification of Alternating Copolymers Based on Vinyl Ethers, Chlorotrifluoroethylene, and
Paris-Sud XI, Université de
, in dynamic mode, under air, showed decomposition temperatures (Td,10%) higher than 200 °C. Electrochemical recent fuel cells technology, combining the best of both alkaline batteries and solid polymer electrolyte-exchange membranes, do not require noble metals (Pt, Ru...) as catalysts to function, which is one of the main
Structural Requirements and Reaction Pathways in Dimethyl Ether Combustion Catalyzed by Supported Pt Clusters
Iglesia, Enrique
as a convenient energy carrier for distributed power generation, space heating, and diesel replace- ment combustion of DME because of its potential use in power generation and radiant heating devices and its
Crown Ethers Flatten in Graphene for Strong, Specific Binding | ornl.gov
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management Fermi Site OfficeCourse Clusters CourseN
Development of a Dimethyl Ether (DME)-Fueled Shuttle Bus | Department of
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny:Revised Finding of No53197E T A * S HBatteries withAbstract Development
Removal of MTBE and other organic contaminants from water by sorption to high silica zeolites
Anderson, M.A.
Select zeolites with high SiO{sub 2}/Al{sub 2}O{sub 3} ratios were shown to effectively remove methyl tert-butyl ether (MTBE), chloroform, and trichloroethylene (TCE) from water. In laboratory studies using batch sorption equilibria, high Si large-port mordenite and ZSM-5 (silicalite) were found to have sorption properties for MTBE and TCE superior to activated carbon. for example, at an equilibrium solution concentration of 100 {micro}g/L, high Si mordenite retained 8--12x more MTBE than either of two powdered activated carbons used as reference sorbents. Sorption results also highlight the importance of pore size and SiO{sub 2}/Al{sub 2}O{sub 3} ration on contaminant removal efficiencies by zeolites.
Song Jin; Paul Fallgren
Western Research Institute (WRI), in conjunction with the U.S. Department of Energy (DOE), conducted a study of using the layered double hydroxides (LDH) as filter material to remove microorganisms, large biological molecules, certain anions and toxic oxyanions from various waste streams, including wastewater from refineries. Results demonstrate that LDH has a high adsorbing capability to those compounds with negative surface charge. Constituents studied include model bacteria, viruses, arsenic, selenium, vanadium, diesel range hydrocarbons, methyl tert-butyl ether (MTBE), mixed petroleum constituents, humic materials and anions. This project also attempted to modify the physical structure of LDH for the application as a filtration material. Flow characterizations of the modified LDH materials were also investigated. Results to date indicate that LDH is a cost-effective new material to be used for wastewater treatment, especially for the treatment of anions and oxyanions.
Coadsorption of methanol and isobutene on HY zeolite
Kogelbauer, A.; Goodwin, J.G. Jr. [Univ. of Pittsburgh, PA (United States); Lercher, J.A. [Univ. of Twente, Enschede (Netherlands)
In order to develop a better understanding of methyl tert-butyl ether (MTBE) synthesis on zeolites, the coadsorption of methanol and isobutene on HY zeolite was investigated using IR spectroscopy. Initial adsorption of isobutene alone at 35{degree}C led to rapid oligomerization yielding strongly bound oligomers. The subsequent coadsorption of methanol did not induce any changes in the zeolite-adsorbate complexes. TPD following the coadsorption showed that the Bronsted acid sites could be restored by temperature treatment above approximately 300{degree}C. When methanol was adsorbed first and isobutene was subsequently coadsorbed, MTBE was formed even at 35{degree}C on the catalyst surface. MTBE desorbed easily at a temperature of 70{degree}C, restoring a major fraction of the Bronsted acid sites. Methanol was concluded to decrease the probability of oligomerization by effectively competing for the acid sites. 34 refs., 6 figs.
US refiners choose variety of routes to MTBE
Rhodes, A.K.
This paper reports that refiners and merchant manufacturers in the U.S. are gearing up to produce the large volumes of methyl tertiary butyl ether (MTBE) needed to comply with oxygenated gasoline requirements. The 1990 U.S. Clean Air Act Amendments specify that, as of the first of this coming November, gasoline containing a minimum of 2.7 wt % oxygen must be sold in 39 CO-nonattainment cities. Refiners and others are scurrying to bring MTBE capacity on line in time to meet this requirement. Many U.S. refiners already have some operating MTBE capacity, but this will not be nearly enough to meet the looming increase in demand. As a result, additional capacity is being constructed worldwide.
Korean oxygenates rule sparks MTBE capacity plans
Kim, Hyung-Jin
The Korean government`s strict standard for gasoline sold domestically is expected to have a significant impact on the methyl tert-butyl ether (MTBE) market. The mandate-requiring gasoline oxygen content of 0.5% this year, 0.75% by 1996, and 1.0% by 1998-has sparked a rush by Korean refineries to build new MTBE plants. If expansion plans are carried out, Korea`s MTBE capacity will increase from 280,000 m.t./year to 650,000 m.t./year by 1996, far surpassing predicted demand. Honam Oil, part of the Lucky Group, plans startup of a 100,000-m.t./year unit at Yeochon by early 1996. In addition, by the end of 1996 Ssangyong Oil will bring a 100,000-m.t./year unit onstream.
Ecofuel plans MTBE plant in Italy
Alperowicz, N.
Ecofuel (Milan), an ENI company, is evaluating construction of a new methyl tert-butyl ether (MTBE) plant in Italy, but has shelved plans for a world-scale MTBE unit in Mexico. The Italian unit is tied to ethylene expansion now under way. Later this year EniChem (Milan), a sister company, is due to complete construction of a 360,000-m.t./year cracker at Brindisi. The C{sub 4} stream available there and from the existing cracker at Priolo in Sicily should provide enough feed for a unit of up to 100,000 m.t./year of MTBE capacity. Some of the feedstock could also come from the Ravenna cracker.
Proton NMR analysis of octane number for motor gasoline: Part V
Ichikawa, M.; Nonaka, N.; Amano, H.; Takada, I.; Ishimori, S. [Suzuki Motor Corp., Hamamatsu (Japan); Andoh, H.; Kumamoto, K. [Showa Shell Sikiyu Tokyo (Japan)
A method to predict the octane number of automobile gasoline containing methyl tert-butyl ether (MTBE) by proton magnetic resonance (PMR) spectrometry was studied. Samples of gasoline whose octane numbers had been identified according to the ASTM standards (commercially available premium gasoline to which MTBE was added at rates of 7 vol % and 14 vol %) were used in this investigation of the effect of MTBE on the octane number. The findings were utilized to introduce a term regarding MTBE into the previously reported linear regression equation for estimating the octane number from the PMR spectrum, and the appropriateness of the linear regression equation was assessed. As a result the MTBE contents in the sample were determined with satisfactory accuracy by using a standard addition method, and a linear regression equation reflecting the effect of MTBE was obtained. These achievements are reported. 11 refs., 3 figs., 5 tabs.
A screening model for evaluating the degradation and transport of MTBE and other fuel oxygenates in the subsurface
Sun, Y; Lu, X
Methyl tert-butyl ether (MTBE) has received high attention as it contributed to cleaner air and contaminated thousands of underground storage tank sites. Because MTBE is very water soluble, it is more difficult to remove from water by conventional remediation techniques. Therefore, biodegradation of MTBE has become a remediation alternative. In order to understand the transport and transformation processes, they present a closed form solution as a screening tool in this paper. The possible reaction pathways of first-order reactions are described as a reaction matrix. The singular value decomposition is conducted analytically to decouple the partial differential equations of the multi-species transport system coupled by the reaction matrix into multiple independent subsystems. Therefore, the complexity of mathematical description for the reactive transport system is significantly reduced and analytical solutions may be previously available or easily derived.
MTBE, ethanol rules come under fire
Begley, R.
EPA is facing stiff challenges to the mandates for methyl tert-butyl ether (MTBE) and ethanol in its reformulated gasoline (RFG) program. Wisconsin officials are receiving hundreds of complaints about the alleged health effects and other problems with MTBE added to gasoline, and Gov. Tommy Thompson is demanding that EPA suspend the RFG program until April 1. Rep. James Sensenbrenner (R., WI) is threatening to introduce a bill to repeal the program in Wisconsin if EPA does not comply. However, EPA administrator Carol Browner says the agency will {open_quotes}defer any decision{close_quotes} on the request. EPA has sent technical experts to Milwaukee to respond to and monitor citizens` complaints.
Ecological hazards of MTBE exposure: A research agenda
Carlsen, T.; Hall, L.; Rice, D.
Fuel oxygenates are used in metropolitan areas across the United States in order to reduce the amount of carbon monoxide released into the atmosphere during the winter. The most commonly used fuel oxygenate is Methyl tert-butyl ether (MTBE). Its widespread use has resulted in releases into the environment. To date there has been only minimal effort to investigate ecological impacts caused by exposure to concentrations of MTBE typically found in environmental media. Research into the potential for MTBE to adversely affect ecological receptors is essential. Acquisition of such baselines data is especially critical in light of continuing inputs and potential accumulation of MTBE in environmental media. A research Agenda is included in this report and addresses: Assessing Ecological Impacts, Potential Ecological Impacts of MTBE (aquatic organisms, terrestrial organisms), Potential Ecological Endpoints, and A Summary of Research Needs.
Gas phase synthesis of MTBE on triflic-acid-modified zeolites
Nikolopoulos, A.A.; Kogelbauer, A.; Goodwin, J.G. Jr. [Univ. of Pittsburgh, PA (United States)] [and others] [Univ. of Pittsburgh, PA (United States); and others
The gas phase synthesis of MTBE (methyl tert-butyl ether) was studied using three series of triflic acid (TFA)-modified zeolites, the parent materials being HY, H-mordenite, and HZSM-5. Impregnation with TFA was found to enhance MTBE synthesis activity only for the large-pore zeolite Y and only up to a certain extent of modification. A high level of TFA modification caused a reduction in activity, apparently due to blockage of the active sites by TFA molecules and extra-lattice Al formed during the modification process. The mechanism of activity enhancement by TFA modification appears to be related to the formation of extra-lattice Al rather than the direct presence of TFA. 20 refs., 6 figs., 1 tab.
MTBE: The headache of cleaner air
Kneiss, J.
Gasoline with methyl tertiary butyl ether (MTBE) has been sold in the United States since 1979, when it was added to fuels as an octane enhancer after lead was phased out of motor fuels. Recently it has been introduced as a means of reducing carbon monoxide emissions during the winter months in targeted US cities. However, there is concern over health complaints including headaches, dizziness and nausea from residents of some areas. These reports have launched an era of assidious research by scientists and public health officials across the country to learn more about MTBE`s short-term and long-term, and possibly carcinogenic, health effects. New research should help weigh the risk of MTBE as a possible carcinogen and the effectiveness of MTBE-blended fuels in reducing carbon monoxide levels. The question is whether, in minimizing one risk, is another risk - however small - being introduced?
Toxicological and performance aspects of oxygenated motor vehicle fuels
At the request of the Environmental Protection Agency, the committee reviewed a draft of a federal report that assesses the effects of oxygenated fuels on public health, air quality, fuel economy, engine performance, and water quality. The committee determined that much of the federal report adequately represents what is known about the effects of methyl tertiary-butyl ether (MTBE) -- the most commonly used additive in the federal oxygenated-fuels program -- on health, the environment, and motor vehicles. MTBE, a chemical added to gasoline to reduce carbon monoxide pollution, appears not to pose a substantial human health risk, but more-definitive data are needed to assess short-term health effects and to determine whether this additive is effective in reducing carbon monoxide pollution in cold environments.
Lyondell`s new isobutylene route could fuel an MTBE capacity boost
Rotman, D.; Wood, A.
Driven by the hot growth prospects for methyl tert-butyl ether (MTBE), Lyondell Petrochemical (Houston) has developed a route to isobutylene it claims can produce the MTBE feedstock at half the capital cost of alternative synthesis technology. If proved, the process will be used in a new 7500-10,000 bbl/day MTBE plant at Channelview, TX. Lyondell also hopes to license the technology. {open_quotes}With expanding MTBE capacity, we will have to have new routes to isobutylene,{close_quotes} says Bob G. Gower, president and CEO of Lyondell. {open_quotes}We think this is a good fit within Lyondell, but also that it is important technology.{close_quotes} Gower declines to detail its specifics, but says it is a one-step isomerization of n-butenes to isobutylene. The firm has tested the process at a pilot unit and plans a demonstration unit in 1992.
Photocatalytic reactions of oxygenates on tropospheric oxide particles
Idriss, H.; Seebauer, E.G.; Miller, A. [Univ. of Illinois, Urbana, IL (United States)
Oxygenates such as ethanol and tert-butyl methyl ether (MTBE) are finding increased use as additives to fuels. The relative merits of ethanol and MTBE have become the focus of intense debate with their ultimate fate as fugitive emissions representing one aspect of this controversy. Both species are known to react homogeneously with photogenerated OH radicals. Here we show that both can also photoreact on suspended solid particulates in the atmosphere with rates comparable to those of OH reactions. Heterogeneous reactions of ethanol yield acetaldehyde and those of MTBE give isobutene and formaldehyde (carcinogenic). Experiments by spectroscopic and kinetic techniques show that the active phases in fly ash are Fe and Ti oxides. In addition, the effects of humidity and alkali addition on the activity and selectivity of these reactions are also discussed. This work appears to be the first demonstration that volatile organic compounds can react as fast by a heterogeneous mechanism as by a homogeneous one in the atmosphere.
Snamprogetti signs MTBE contracts
Alperowicz, N.
Snamprogetti (Milan) will use a Russian-developed dehydrogenation process in a world-scale methyl tert-butyl ether (MTBE) plant it is to build at Arzew, Algeria for a previously announced joint venture of Sonatrach (Algiers), Total (Paris), and Ecofuel (Milan). The 600,000-m.t./year plant will be the first in the West to use the improved Snamprogetti-Yarsintez fluidized-bed dehydrogenation (FBD) technology proven on a demonstration plant at Yaroslavl, Russia. The process has also been selected for use in Oxyfuel Corp.`s 500,000-m.t./year MTBE plant near Beaumont, TX. Although the environmental permit is already in place, final agreement for this project has not yet been signed.
Lucas, A.
Methyl tert-butyl ether (MTBE) producers were looking for a boost from the official New Year`s start of EPA`s reformulated gasoline (RFG) program. But that prospect has been dimmed by an EPA-proposal-in reaction to concerns about RFG prices-to allow states to withdraw from the program. The states that have opted to out make up 5%-6% of the total RFG pool says Arthur Zadronzy, director/government outreach for MTBE producer Arco Chemical. {open_quotes}This is not a major hit, but it is one we have felt,{close_quotes} he says. Despite the state and EPA actions, MTBE producers are not worried about long-term consequences.
Vapor-liquid equilibria of hydrocarbons and fuel oxygenates. 2
Bennett, A.; Lamm, S.; Orbey, H.; Sandler, S.I. (Univ. of Delaware, Newark (United States))
Vapor-liquid equilibrium data for methyl tert-butyl ether (MTBE) + 1-heptene, MTBE + four-component gasoline prototype, ethanol + four-component gasoline prototype, and separately MTBE and ethanol with the Auto/Oil Air Quality Improvement Research Gasoline Blend A are reported. Small additions of MTBE have a very small effect on the total equilibrium pressure of this gasoline blend, and at most temperatures will decrease this pressure. In contrast, small additions of ethanol to this gasoline blend result in a significant increase in the equilibrium pressure at all temperatures. Analysis shows that the vapor-liquid equilibrium data for the MTBE-containing systems are easily correlated using a modified Peng-Robinson equation of state with conventional van der Waals one-fluid mixing rules. Data for mixtures containing ethanol cannot be accurately correlated in this way.
MTBE movements between Texas Gulf Coast plants to be enhanced
Not Available
This paper reports that Texas Eastern Products Pipeline Co. (Teppco), Houston, has begun construction of its shuttle pipeline, a 10-mile, 6 and 8-in. line to move methyl tertiary butyl ether (MTBE) between producers and refiners along the Houston Ship Channel. Funding for the project has been approved, rights-of-way are secured, and procurement of materials is under way, according to Teppco. The line will flow from the western edge of Shell's refinery eastward to storage facilities of Teppco's Baytown terminal. The shuttle pipeline anticipates the US requirement for oxygenated gasolines that takes effect Nov. 1. Approximately 70% of the available US merchant capacity for MTBE is located along the shuttle's path, Teppco says.
Self-ignition of S.I. engine model fuels: A shock tube investigation at high pressure
Fieweger, K.; Blumenthal, R.; Adomeit, G. [RWTH, Aachen (Germany). Inst. fuer Allegemeine Mechanik] [RWTH, Aachen (Germany). Inst. fuer Allegemeine Mechanik
The self-ignition of several spark-ignition (SI) engine fuels (iso-octane, methanol, methyl tert-butyl ether and three different mixtures of iso-octane and n-heptane), mixed with air, was investigated experimentally under relevant engine conditions by the shock tube technique. Typical modes of the self-ignition process were registered cinematographically. For temperatures relevant to piston engine combustion, the self-ignition process always starts as an inhomogeneous, deflagrative mild ignition. This instant is defined by the ignition delay time, {tau}{sub defl}. The deflagration process in most cases is followed by a secondary explosion (DDT). This transition defines a second ignition delay time, {tau}{sub DDT}, which is a suitable approximation for the chemical ignition delay time, if the change of the thermodynamic conditions of the unburned test gas due to deflagration is taken into account. For iso-octane at p = 40 bar, a NTC (negative temperature coefficient), behavior connected with a two step (cool flame) self-ignition at low temperatures was observed. This process was very pronounced for rich and less pronounced for stoichiometric mixtures. The results of the {tau}{sub DDT} delays of the stoichiometric mixtures were shortened by the primary deflagration process in the temperature range between 800 and 1,000 K. Various mixtures of iso-octane and n-heptane were investigated. The results show a strong influence of the n-heptane fraction in the mixture, both on the ignition delay time and on the mode of self-ignition. The self-ignition of methanol and MTBE (methyl tert-butyl ether) is characterized by a very pronounced initial deflagration. For temperatures below 900 K (methanol: 800 K), no secondary explosion occurs. Taking into account the pressure increase due to deflagration, the measured delays {tau}{sub DDT} of the secondary explosion are shortened by up to one order of magnitude.
Synthesis of octane enhancers during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 6, January 1, 1992--March 31, 1992
Marcelin, G.
The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl ether (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: (1) Addition of isobutylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch. (2) Addition of isobutylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst. (3) Addition of methanol to slurry phase FT synthesis making iso-olefins. During the sixth quarter we completed the construction of the slurry bubble column reactor (SBCR), conducted initial shake-down experiments in a cold-flow mode, and finalized the selection process of the acid catalysts for conversion of syngas-produced alcohols and isobutylene to MTBE (scheme 2). Tasks 3, 4, and 5 are awaiting complete implementation of the SBCR system.
Evaluating nonmetallic materials` compatibility with MTBE and MTBE + gasoline service
Hotaling, A.C.
Methyl-tertiary-butyl-ether (MTBE) has become the leading oxygenate in use in the petroleum industry. Since its introduction several years ago there has been premature deterioration of nonmetallic materials in both neat MTBE and MTBE + gasoline. This degradation is costly in several ways: maintenance, replacement, environmental, and product-loss. Identifying nonmetallic materials compatible with MTBE and MTBE + gasoline is important to the petroleum industry -- all the way from the refinery to the retail sale. Exposure tests have been conducted with different types of nonmetallics in neat MTBE, neat MTBE vapor, and 5% MTBE + 95% gasoline. As in previously reported tests, Teflon{reg_sign} laminates were the top performers, experiencing very little change in any of the properties tested. An ester and ether-based urethane laminate also exhibited only small property changes. Most materials displayed significant deterioration of one or more of the measured properties, even in MTBE condensing vapor and the 5% MTBE + 95% gasoline. The specific effects on each material need to be individually evaluated to determine the effect on service life.
23/11/2009 S&I meeting 2009 1 NanoparticleNanoparticle--polymerpolymer
Strathclyde, University of
Divinyl ether-based polymer: HTP3 HTP3 components: 1,4-cyclohexyldimethanol divinyl ether (CHDV) monomer
A study of the condensation of primary, secondary, and tertiary butyl alcohols with benzene in the presence of anhydrous ferric chloride
Dodson, Ralph Jordan
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Office of Environmental Management (EM)
gases-including nitrogen, carbon dioxide, hydrogen sulfide, methane, ethane, and propane-and butanes and other volatile liquids) composition, and flash gas composition....
Concentrations and Size Distributions of Particulate Matter Emissions...
Broader source: Energy.gov (indexed) [DOE]
ECD-1 CRT CNG1 CNG2 Carbonyl Compounds (Air Toxics) Formaldehyde Acetaldehyde Acetone Acrolein Propionaldehyde Croton Methyl ethyl Ketone (MEK) Methylacrolein Butanal Benzaldehyde...
Maximizing Power Output in Homogeneous Charge Compression Ignition (HCCI) Engines and Enabling Effective Control of Combustion Timing
Saxena, Samveg
the Energy Balance of Ethanol Fuels , for Applied Energyadditive are explored in Ethanol fuel. 8.2.1 Autoignition offuels Fuel Methane Propane Butane Gasoline Ethanol AFR
Measuringthe Atomic or,Molecular Mass of a Gas with aifire Gauge and atutane Lighter Fluid Can
Bodner, George M.
). Hopkins. D. E., J. C~EM.EDVC., 53,718 (1976). 4Davenport,D. A,, ". CmM. EDLC..53,306(1976). "Butane
Airborne measurement of OH reactivity during INTEX-B
plus OH sign), reactiv- propane ing different gases gases atisoprene (plus sign), propane (star) and propene (triangle).NMHC includes ethane, ethene, propane, propene, i-butane, n-
Thermo-fluid Dynamics of Flash Atomizing Sprays and Single Droplet Impacts
Vu, Henry
flashing propane jets. Part two: droplet size distribution.distribution evolution after continuous or intermittent injection of butane or propaneflashing propane jets. Part two: droplet size distribution.
Quantum cascade laser investigations of CH4 and C2H2 interconversion in hydrocarbon/H2 gas mixtures during microwave plasma
Bristol, University of
described in Mankelevich et al. J. Appl. Phys. 104, 113304 2008 . The gas temperature distribution within source gases investigated methane, acetylene, ethane, propyne, propane, and butane are converted
Title: KUPPS Procurement Matrix Purpose: To provide the preferred purchase and/or payment method for various transaction types
vehicle Fuel, diesel, karosene, propane, butane Pcard Office and Research Supplies and Consumables - 137200 137200 - Computer Supplies Consumables: Flash Drives, storage media, toner cartridges Replacement
Natural gas treatment process using PTMSP membrane
Toy, L.G.; Pinnau, I.
A process is described for separating C{sub 3}+ hydrocarbons, particularly propane and butane, from natural gas. The process uses a poly(trimethylsilylpropyne) membrane. 6 figs.
Natural gas treatment process using PTMSP membrane
Toy, Lora G. (San Francisco, CA); Pinnau, Ingo (Palo Alto, CA)
A process for separating C.sub.3 + hydrocarbons, particularly propane and butane, from natural gas. The process uses a poly(trimethylsilylpropyne) membrane.
Alkaline-Side Extraction of Cesium from Savannah River Tank Waste Using a Calixarene-Crown Ether Extractant
Bonnesen, P.V.; Delmau, L.H.; Haverlock, T.J.; Moyer, B.A.
Results are presented supporting the viability of the alkaline-side CSEX process as a potential replacement for the In-Tank Precipitation process for removal of cesium from aqueous high-level waste (HLW) at the Savannah River Site (SRS). Under funding from the USDOE Efficient Separations and Crosscutting program, a flowsheet was suggested in early June of 1998, and in the following four months, this flowsheet underwent extensive testing, both in batch tests at ORNL and ANL and in two centrifugal-contactor tests at ANL. To carry out these tests, the initial ESP funding was augmented by direct funds from Westinghouse Savannah River Corporation. The flowsheet employed a solvent containing a calixarene-crown hybrid compound called BoBCalixC6 that was invented at ORNL and can now be obtained commercially for government use from IBC Advanced Technologies. This special extractant is so powerful and selective that it can be used at only 0.01 M, compensating for its expense, but a modifier is required for use in an aliphatic diluent, primarily to increase the cesium distribution ratio D{sub Cs} in extraction. The modifier selected is a relatively economical fluorinated alcohol called Cs3, invented at ORNL and so far available. only from ORNL. For the flowsheet, the modifier is used at 0.2 M in the branched aliphatic kerosene Isopar{reg_sign} L. Testing at ORNL and ANL involved simulants of the SRS HLW. After extraction of the Cs from the waste simulant, the solvent is scrubbed with 0.05 M HNO{sub 3} and stripped with a solution comprised of 0.0005 M HNO{sub 3} and 0.0001 M CsNO{sub 3}. The selection of these conditions is justified in this report, both on the basis of experimental data and underlying theory.
DOI: 10.1002/chem.200902350 Rigid-Strut-Containing Crown Ethers and [2]Catenanes for Incorporation
Yaghi, Omar M.
as templates in the construction of me- chanically interlocked molecules (MIMs), such as catenanes (BPP34C10DA), and dicarboxylic acid 1,5-naphthoparaphenylene[36]crown-10 (NPP36C10DA). These novel10DA was determined by X- ray crystallography. The NPP36C10DA-based [2]catenane (H2NPP36C10DC-CAT·4PF
Gold(I)-catalyzed formation of furans by a Claisen-type rearrangement of ynenyl allyl ethers
Paris-Sud XI, Université de
June 2011 This article is part of the Thematic Series "Gold catalysis for organic synthesis". Guest in this field which have led to the development of a new procedure for the synthesis of polysubstituted furans of furans. Scheme 2: Synthetic approach to functionalized furans. ized pyrroles 3 (X = NTs) in the presence
Investigation of HCCI Combustion of Diethyl Ether and Ethanol Mixtures Using Carbon 14 Tracing and Numerical Simulations
Mack, John Hunter; Flowers, Daniel L.; Buchholz, Bruce A.; Dibble, Robert W
Ryan III, and J.S. Souder, "HCCI Operation of a Dual-FuelJ. Girard, and R. Dibble, "HCCI in a CFR Engine: Experimentsthe DOE University HCCI Program, and LLNL Laboratory
Process Design, Simulation and Integration of Dimethyl Ether (DME) Production from Shale Gas by Direct and Indirect Methods
Karagoz, Secgin
are methanol synthesis and dehydration of the methanol to DME. Another way to produce DME is the direct synthesis of DME from syngas. In order to use DME as a fuel alternative, it must be produced at low cost in large quantities. The purpose of this study...
Insight into Selected Reactions in Low-Temperature Dimethyl Ether Combustion from Born-Oppenheimer Molecular Dynamics
Carter, Emily A.
fuel, which is comprised of long-chain hydrocarbons. Unlike conventional diesel fuel, DME creates for conventional diesel fuel. DME's propensity to compression ignite is comparable to that of conventional diesel
Task 4.9 -- Value-added products from syngas. Semi-annual report, July 1--December 31, 1996
Olson, E.S.; Sharma, R.K.
The work on advanced fuel forms in 1996 focused on the synthesis of higher alcohols from mixtures of hydrogen and carbon dioxide (syngas) from coal gasification. Initial work in this project utilized a novel molybdenum sulfide catalyst previously shown to be active for hydrodesulfurization reactions of coal liquids. A pressurized fixed-bed flow-through reactor was constructed, and the MoS{sub 2} catalysts were tested with syngas under a variety of conditions. Unfortunately, the catalysts, even with higher molybdenum loading and addition of promoters, failed to give alcohol products. A batch reactor test of the catalyst was also conducted, but did not produce alcohol products. Group VIII metals have been used previously in catalysts for syngas reactions. Ruthenium and rhodium catalysts were prepared by impregnation of a hydrotalcite support. Tests with these catalysts in flow-through reactors also did not produce the desired alcohol products. The formation of higher alcohols from smaller ones, such as methanol and ethanol, could be commercially important if high selectivity could be achieved. The methanol and ethanol would be derived from syngas and fermentation, respectively. Based on previous work in other laboratories, it was hypothesized that the hydrotalcite-supported MoS{sub 2} or Ru or Rh catalysts could catalyze the formation of butyl alcohols. Although the desired 1-butanol was obtained in batch reactions with the promoted ruthenium catalyst, the reaction was not as selective as desired. Product suitable for a lower-vapor-pressure gasoline oxygenate additive was obtained, but it may not be economical to market such products in competition with methyl tertiary-butyl ether (MTBE). Flow-through catalytic bed reactions were not successful.
Kinetic and Inhibition Studies for the Aerobic Cometabolism of
Semprini, Lewis
was indicated from direct linear plots, and the CAHs also competitively inhibited butane utilization. 1,1-DCE indicator of competitive inhibition ob- served. Butane was a strong inhibitor of CAH transfor- mation different inhibition types were ob- served among the compounds. Competitive inhibition among CAHs
Atmos. Chem. Phys., 9, 74917504, 2009 www.atmos-chem-phys.net/9/7491/2009/
Meskhidze, Nicholas
. This work is distributed under the Creative Commons Attribution 3.0 License. Atmospheric Chemistry most abundant VOCs observed in the tunnel were, in decreasing order, ethene, toluene, n-butane, propane. The high propane and n-butane emissions were found to be associated with liq- uefied petroleum gas (LPG
Experimental and artificial neural network modeling study on soot formation in premixed hydrocarbon flamesq
Senkan, Selim M.
The formation of soot in premixed flames of methane, ethane, propane, and butane was studied at three different particle diameters at higher distances above the burner surface and propane, ethane, and butane flames came conditions in humans. Polycyclic aromatic hydro- carbons (PAH), the largest class of chemical carcinogens
A review of the environmental behavior and fate of fuel oxygenates
Squillace, P.J.
The ways in which fuel oxygenate compounds behave in water, soil, and air are determined by how they partition among the different media. The behavior of a gasoline oxygenate in water is affected by the oxygenate`s (1) solubility in water from gasoline: (2) partitioning between water and soil materials; and (3) partitioning between air and water. Water in equilibrium with oxygenated gasoline can contain high concentrations of the oxygenate. For example, at room temperature water solubility of methyl tert-butyl ether (MTBE) will be about 5,000 mg/L for a gasoline that is 10% MTBE by weight. In contrast, the total hydrocarbon solubility in water is typically about 120 mg/L for nonoxygenated gasoline. Fuel oxygenates sorb only weakly to soil and aquifer materials. Therefore, sorption to these materials will not significantly retard their transport by ground water. Fuel oxygenates tend to partition into atmospheric water, including precipitation. For example, washout of gas-phase MTBE by precipitation would not, by itself, greatly alter the gas-phase concentration of the compound in the atmosphere. Nevertheless, the partitioning of MTBE to precipitation is strong enough to allow for submicrogram per liter to 3 pg/L or more inputs of MTBE to ground water and surface water. Occurrence data for MTBE in water and air supports partition theoretical calculations. MTBE and other alkyl ether oxygenates have half lives in the atmosphere that range from about 1 to 14 days. These compounds are generally considered recalcitrant in ground water; whereas ethanol and methanol will readily undergo microbial degradation except where present in concentrations toxic to microorganisms.
Coal transformation chemistry third quarterly progress report
Stock, Leon M.; Blain, D. A.; Handy, C. I.; Huang, C. B.; King, H. H.; Landschulz, W.; Willis, R. S.
A Colorado subbituminous coal was reacted with potassium and naphthalene in tetrahydrofuran. This was then alkylated with n-butyl iodide and the solubility in tetrahydrofuran was determined. The solubility was found to be less than in a corresponding reaction with Illinois No. 6 coal. The solubilization of a Colorado subbituminous coal by reacting it with potassium in liquid ammonia, followed by alkylation is discussed. The preliminary results from a reaction of Illinois No. 6 coal with tetrabutylammonium hydroxide and methyl iodide are reported. Reductive acylation of coal is being studied at the present time using trifluoroacetic anhydride as a quenching reagent. /sup 19/F is a candidate for nmr studies and chemical shifts for trifluoroacetyl derivatives of phenols, thiols, and amides indicate that fluorine may be useful as a sensitive probe for reactive species in coal. The effort on donor solvent coal chemistry was directed to the role played by pericyclic reactions in the liquefaction process. The acceptors were reduced by the deuterated donors. The isotopic distribution of the reduction product indicates that free radical processes occur preferentially. Thus, the pericyclic reactions appear to be unimportant at the threshold reaction temperatures of 350 to 425/sup 0/C. The reactions of aromatic ethers with inorganic sulfide at 400/sup 0/C produces thiophenols.
Heterogeneous catalytic process for alcohol fuels from syngas. Final technical report
Dombek, B.D.
The primary objective of this project has been the pursuit of a catalyst system which would allow the selective production from syngas of methanol and isobutanol. It is desirable to develop a process in which the methanol to isobutanol weight ratio could be varied from 70/30 to 30/70. The 70/30 mixture could be used directly as a fuel additive, while, with the appropriate downstream processing, the 30/70 mixture could be utilized for methyl tertiary-butyl ether (MTBE) synthesis. The indirect manufacture of MTBE from a coal derived syngas to methanol and isobutanol process would appear to be a viable solution to MTBE feedstock limitations. To become economically attractive, a process fro producing oxygenates from coal-derived syngas must form these products with high selectivity and good rates, and must be capable of operating with a low-hydrogen-content syngas. This was to be accomplished through extensions of known catalyst systems and by the rational design of novel catalyst systems.
Fast photoreactions of ethanol and MTBE on tropospheric metal oxide particles
Idriss, H.; Seebauer, E.G. [Univ. of Illinois, Urbana, IL (United States)
Ethanol (EtOH) and tert-Butyl methyl ether (MTBE) are both finding increased use as oxygenated additives to fuels. However, the environmental fate in the troposphere of these species is unclear when they escape as fugitive emissions. In several locations there are reports of human illness in response to MTBE in particular. Volatile organic compounds (VOC`s) such as these are generally thought to react by a variety of homogeneous free-radical mechanisms, usually beginning with attack by OH radical. However, we show by laboratory kinetic studies that the heterogeneous photoreaction on solid suspended metal-oxide particulates such as fly ash proceeds with a comparable rate, especially in urban environments. EtOH reacts to form acetaldehyde, and EtOH forms isobutene, methanol, and formaldehyde. Our work appears to be the first-ever demonstration that VOC`s can react as fast by a heterogeneous mechanism as by a homogeneous one in the atmosphere. Experiments by various optical and kinetic techniques show that the active phases in fly ash are Fe oxides, which are fairly abundant in other atmospheric particulates as well.
High-temperature ignition of propane with MTBE as an additive: Shock-tube experiments and modeling
Gray, J.A. (Sandia National Labs., Livermore, CA (United States)); Westbrook, C.K. (Lawrence Livermore National Lab., CA (United States))
Ignition of propane has been studied in a shock tube and by computational modeling to determine the effect of methyl tert-butyl ether (MTBE) as a fuel additive. MTBE and isobutene were added in amounts up to 25% of the fuel to propane-oxygen-argon mixtures in shock-tube experiments covering a range of temperatures between 1450 and 1800 K. Ignition delays were measured from chemiluminescence at 432 nm due to excited CH radicals. The temperature dependence of the ignition rates was analyzed to yield Arrhenius parameters of E{sub a}{approximately}40 kcal/mol and log (A){approximately} 9.0 sec{sup {minus}1} for the overall reaction. Reactions involving MTBE and its decomposition products were combined with an established propane mechanism in a numerical model to describe the kinetic interaction of this additive with a typical hydrocarbon fuel. The experiments and the kinetic model both show that MTBE and isobutene retard propane ignition with nearly equal efficiency. The kinetic model demonstrates that isobutene kinetics are responsible for inhibition by both MTBE and isobutene, and the specific elementary reactions which produce this behavior are identified.
Modeling the atmospheric inputs of MTBE to groundwater systems
Pankow, J.F.; Johnson, R.L. [Oregon Graduate Inst., Portland, OR (United States). Dept. of Environmental Science and Engineering; Thomson, N.R. [Univ. of Waterloo, Ontario (Canada). Dept. of Civil Engineering
A numerical transport model was used to calculate the movement of methyl-t-butyl ether (MTBE) and several other volatile organic compounds (VOCs) from the atmosphere downward through the unsaturated zone and into shallow groundwater. Simulations were carried out for periods as long as 10 years to investigate whether a gaseous atmospheric MTBE source at typical ambient concentrations could account for the presence of MTBE in shallow groundwater at the types of low ug/L levels that have been found during the National Water Quality Assessment Program currently being conducted by the US Geological Survey. The simulations indicate that downward movement of MTBE to shallow groundwater will be very slow when there is no net downward movement of water through the vadose zone. For example, for a vadose zone composed of fine sand, and assuming tens of cm of infiltration, then only a few years will be required for water at a water table that is 5.0 m below ground surface to attain MTBE levels that correspond to saturation with respect to the atmospheric source gaseous concentration. An on/off atmospheric source, as might occur in the seasonal use of MTBE, will lead to concentrations in shallow groundwater that correspond to saturation with the time-averaging atmospheric source concentration.
Meeting the challenge of MTBE biodegradation
Eweis, J.B.; Chang, D.P.Y.; Schroeder, E.D.; Scow, K.M. [Univ. of California, Davis, CA (United States); Morton, R.L.; Caballero, R.C. [Los Angeles County Sanitation Districts, Carson, CA (United States). Joint Water Pollution Control Plant
Oxygenated and reformulated gasolines have been developed in response to air pollution control regulations targeted at reducing carbon monoxide emissions and photochemical air pollution. The 1990 Clean Air Act Amendments required the addition of fuel oxygenates to gasoline in areas where the level of carbon monoxide exceeded national ambient air quality standards. In the South Coast Air Basin gasoline containing oxygenated compounds has been in use since the late 1980`s. One oxygenated fuel additive most often selected by producers to meet the requirements is methyl tert-butyl ether (MTBE). However, large production numbers associated with MTBE production, combined with the compound`s high water solubility, chemical stability, and toxicity, make it a potentially important groundwater pollutant. The County Sanitation District of Los Angeles, Joint Water Pollution Control Plant in Carson, California is one of the few wastewater treatment plants in the nation that receives refinery wastewater discharge. It has operated several pilot-scale compost-based biofilters for control of various volatile organic contaminants throughout the plant since a 1991 joint study with the University of California, Davis. After one year of operation, one of the biofilters spontaneously developed the ability to degrade MTBE. The paper describes the collaborative efforts to determine the feasibility of transferring the degrading microbial population from the solid to liquid phase, without loss of activity, and to determine some of the environmental requirements necessary for survival of the microbial culture.
Synthesis of octane enhancers during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 7, April 1, 1992--June 30, 1992
Marcelin, G.
The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: addition of i-butylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch; addition of i-butylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst; and addition of methanol to slurry phase FT synthesis making iso-olefins. During the seventh quarter we continued the shake down experiments for the SBCR and conducted an initial aborted run. We have also re-started experiments on Scheme 1, i.e., the addition of iso-butylene during CO hydrogenation. Using a dual bed arrangement, we have demonstrated the synthesis of MTBE from syngas and iso-butylene.
Interdisciplinary investigation of subsurface contaminant transport and fate at point-source releases of gasoline containing MTBE
Buxton, H.T.; Baehr, A.L. [Geological Survey, West Trenton, NJ (United States); Landmeyer, J.E. [Geological Survey, Columbia, SC (United States)] [and others
Methyl tert-butyl ether (MTBE) is commonly found at concentrations above the current U.S. Environmental Protection Agency draft lifetime health advisory for drinking water (20 to 200 micrograms per liter) at many point-source gasoline release sites. MTBE is significantly more persistent than benzene, toluene, ethyl-benzene and xylenes (BTEX) in the subsurface. Therefore, evaluation of the implications of its presence in gasoline to monitored natural attenuation and engineered bioremediation alternatives is warranted. An interdisciplinary, field-based investigation of the subsurface transport and fate of MTBE and petroleum hydrocarbons is being conducted by the U.S. Geological Survey (USGS) Toxic Substances Hydrology Program at the site of an underground gasoline storage-tank release near Beaufort, South Carolina. The objective of the investigation is to provide a systematic evaluation of natural attenuation of MTBE compared to BTEX. Results of the field and laboratory studies at this site will be generalized to a broader range of hydrogeochemical conditions through experiments at other sites. Furthermore, newly developed methods of analysis can be applied to sites across the Nation. This investigation of MTBE at point-source release sites is coordinated with investigations of the occurrence of MTBE in shallow ground water, surface water, precipitation, and the atmosphere being conducted by the USGS National Water-Quality Assessment Program.
High-temperature ignition of propane with MTBE as an additive: Shock-tube experiments and modeling. Revision 1
Gray, J.A. [Sandia National Labs., Livermore, CA (United States); Westbrook, C.K. [Lawrence Livermore National Lab., CA (United States)
Ignition of propane has been studied in a shock tube and by computational modeling to determine the effect of methyl tert-butyl ether (MTBE) as a fuel additive. MTBE and isobutene were added to amounts up to 25% of the fuel to propane-oxygen-argon mixtures to shock-tube experiments covering a range of temperatures between 1450 and 1800 K. Ignition delays were measured from chemiluminescence at 432 nm due to excited CH radicals. The temperature dependence of the ignition rates was analyzed to yield Arrhenium parameters of E{sub a}{sup {minus}}40 kcal/mol and log(A) {sup {minus}}9.0 sec{sup {minus}1} for the overall reaction. Reactions involving MTBE and its decomposition products were combined with an established propane mechanism in a numerical model to describe the kinetic interaction of this additive with a typical hydrocarbon fuel. The experiments and the kinetic model both show that MTBE and isobutene retard propane ignition with nearly equal efficiency. The kinetic model demonstrates that isobutene kinetics are responsible for inhibition by both MTBE and isobutene, and the specific elementary reactions which produce this behavior are identified. 19 refs., 1 fig., 3 tabs.
Effects of temperature and acidic pre-treatment on Fenton-driven oxidation of MTBE-spent granular activated carbon
Kan, E.; Huling, S.G. [Robert S. Kerr Environmental Research Center, Ada, OK (United States)
The effects of temperature and acidic pretreatment on Fenton-driven chemical oxidation of methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC, derived from bituminous coal) were investigated. Limiting factors in MTBE removal in GAC include the heterogeneous distribution of amended Fe, and slow intraparticle diffusive transport of MTBE and hydrogen peroxide (H{sub 2}O{sub 2}) into the 'reactive zone'. Acid pretreatment of GAC before Fe amendment altered the surface chemistry of the GAC, lowered the pH point of zero charge, and resulted in greater penetration and more uniform distribution of Fe in GAC. This led to a condition where Fe, MTBE, and H{sub 2}O{sub 2} coexisted over a larger volume of the GAC contributing to greater MTBE oxidation and removal. H{sub 2}O{sub 2} reaction and MTBE removal in GAC increased with temperature. Modeling H{sub 2}O{sub 2} transport and reaction in GAC indicated that H{sub 2}O{sub 2} penetration was inversely proportional with temperature and tortuosity, and occurred over a larger fraction of the total volume of small GAC particles (0.3 mm diameter) relative to large particles (1.2 mm diameter). Acidic pretreatment of GAC, Fe-amendment, elevated reaction temperature, and use of small GAC particles are operational parameters that improve Fenton-driven oxidation of MTBE in GAC. 29 refs., 6 figs., 1 tab.
Synthesis of MTBE during CO hydrogenation: Reaction sites required
Kazi, A.M.; Goodwin, J.G. Jr.; Marcelin, G.; Oukaci, R. [Univ. of Pittsburgh, PA (United States). Dept. of Chemical and Petroleum Engineering
Synthesis of methyl tert-butyl ether (MTBE) during carbon monoxide (CO) hydrogenation has been studied with the following reaction schemes: (1) the addition of isobutylene during CO hydrogenation over metal catalysts active for methanol synthesis (Pd/SiO{sub 2} and Li-Pd/SiO{sub 2}) and (2) the addition of isobutylene during CO hydrogenation over a dual bed configuration consisting of Li-Pd/SiO{sub 2} and a zeolite (H-ZSM-5 or HY). The addition of isobutylene during methanol synthesis over the supported Pd catalysts indicated that MTBE cannot be formed on metal sites from a reaction of isobutylene with methanol precursors. However, addition of isobutylene to the syngas feed over a dual bed consisting of a methanol synthesis catalyst and an acid zeolite downstream of the methanol synthesis catalyst showed that MTBE can be synthesized during CO hydrogenation provided acid sites are available. In order to get higher conversions of methanol to MTBE, optimization of the acid catalyst and/or reaction conditions would be required to minimize formation of byproduct hydrocarbons.
Intrinsic bioremediation of a BTEX and MTBE plume under mixed aerobic/denitrifying conditions
Borden, R.C.; Daniel, R.A. [North Carolina State Univ., Raleigh, NC (United States). Civil Engineering Dept.
A shallow Coastal Plain aquifer in rural Sampson Country, North Carolina, has been contaminated with petroleum hydrocarbon from a leaking underground storage tank containing gasoline.An extensive field characterization has been performed to define the horizontal and vertical distribution of soluble gasoline components and indicator parameters. A plume of dissolved methyl tert-butyl ether (MTBE) and the aromatic hydrocarbons benzene, toluene, ethylbenzene, and xylene isomers (BTEX) is present in the aquifer and has migrated over 600 ft from the source area. Background dissolved oxygen concentrations range from 7 to 8 mg/L, and nitrate concentrations range from 5 to 22 mg/L as N due to extensive fertilization of fields surrounding the spill. In the center of the BTEX plume, oxygen concentrations decline to less than 1 mg/L while nitrate concentrations remain high. The total mass flux of MTBE and all BTEX components decline with distance downgradient relative to a conservative tracer (chloride). At the source, the total BTEX concentration exceeds 75 mg/L while 130 ft downgradient, total BTEX concentrations are less than 4.9 mg/L, a 15-fold reduction. Toluene and ethylbenzene decline most rapidly followed by m-p-xylene, o-xylene and finally benzene. Biodegradation of TEX appears to be enhanced by the excess nitrate present in the aquifer while benzene biodegradation appears to be due to strictly aerobic processes.
Falling MTBE demand bursts the methanol bubble
Wiesmann, G.; Cornitius, T.
Methanol spot markets in Europe and the US have been hit hard by weakening demand from methyl tert-butyl ether (MTBE) producers. In Europe, spot prices for domestic T2 product have dropped to DM620-DM630/m.t. fob from early-January prices above DM800/m.t. and US spot prices have slipped to $1.05/gal fob from $1.35/gal. While chemical applications for methanol show sustained demand, sharp methanol hikes during 1994 have priced MTBE out of the gasoline-additive market. {open_quotes}We`ve learned an important lesson. We killed [MTBE] applications in the rest of the world,{close_quotes} says one European methanol producer. Even with methanol currently at DM620/m.t., another manufacturer points out, MTBE production costs still total $300/m.t., $30/m.t. more than MTBE spot prices. Since late 1994, Europe`s 3.3-million m.t./year MTBE production has been cut back 30%.
The MTBE solution: Octanes, technology, and refinery profitability
Lander, E.P.; Hubbard, J.N.; Smith, L.A.
This paper has been developed to provide refiners with business decision insight regarding the production of methyl tertiary butyl ether (MTBE) from refinery - (FCC) produced isobutylene. The driving forces making MTBE an attractive investment are examined with regard to the increasing demand for higher octane unleaded gasolines. The decision to proceed with MTBE production depends on the profitability of such an investment and the refiner's ability to meet market demands using available processing equipment, refinery produced streams and external feedstocks. The factors affecting this decision are analyzed in this paper and include: industry ability to meet rising octane demand; profit potential realized by diverting isobutylene to MTBE; availability of technology for producing MTBE; and investment and operating costs required to produce MTBE. Chemical Research and Licensing and NEOCHEM have developed a simple, low cost process to produce MTBE, reducing the excessive equipment and high operating costs that were associated with conventional MTBE designs. The economics and process benefits of installing a CRandL/NEOCHEM MTBE process are examined within the framework of a generalized medium-sized refinery configuration.
Synthesis of octane enhancers during slurry-phase Fischer-Tropsch
Marcelin, G.
The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: addition of i-butylene during the formation of methanol and/or higher alcohols directly from CO and H[sub 2] during slurry-phase Fischer-Tropsch; addition of i-butylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst; and addition of methanol to slurry phase FT synthesis making iso-olefins. During the seventh quarter we continued the shake down experiments for the SBCR and conducted an initial aborted run. We have also re-started experiments on Scheme 1, i.e., the addition of iso-butylene during CO hydrogenation. Using a dual bed arrangement, we have demonstrated the synthesis of MTBE from syngas and iso-butylene.
High-temperature ignition of propane with MTBE as an additive: Shock-tube experiments and modeling
Gray, J.A. [Sandia National Labs., Livermore, CA (United States); Westbrook, C.K. [Lawrence Livermore National Lab., CA (United States)
Ignition of propane has been studied in a shock tube and by computational modeling to determine the effect of methyl tert-butyl ether (MTBE) as a fuel additive. MTBE and isobutene were added in amounts up to 25% of the fuel to propane-oxygen-argon mixtures in shock-tube experiments covering a range of temperatures between 1450 and 1800 K. Ignition delays were measured from chemiluminescence at 432 nm due to excited CH radicals. The temperature dependence of the ignition rates was analyzed to yield Arrhenius parameters of E{sub a}{approximately}40 kcal/mol and log (A){approximately} 9.0 sec{sup {minus}1} for the overall reaction. Reactions involving MTBE and its decomposition products were combined with an established propane mechanism in a numerical model to describe the kinetic interaction of this additive with a typical hydrocarbon fuel. The experiments and the kinetic model both show that MTBE and isobutene retard propane ignition with nearly equal efficiency. The kinetic model demonstrates that isobutene kinetics are responsible for inhibition by both MTBE and isobutene, and the specific elementary reactions which produce this behavior are identified.
Assessing and Managing the Risks of Fuel Compounds: Ethanol Case Study
Layton, D.W.; Rice, D.W.
We have implemented a suite of chemical transport and fate models that provide diagnostic information about the behavior of ethanol (denoted EtOH) and other fuel-related chemicals released to the environment. Our principal focus is on the impacts to water resources, as this has been one of the key issues facing the introduction of new fuels and additives. We present analyses comparing the transport and fate of EtOH, methyl tertiary butyl ether (MTBE), and 2,2,4 trimethyl pentane (TMP) for the following cases (1) discharges to stratified lakes, subsurface release in a surficial soil, (3) cross-media transfer from air to ground water, and (4) fate in a regional landscape. These compounds have significantly different properties that directly influence their behavior in the environment. EtOH, for example, has a low Henry's law constant, which means that it preferentially partitions to the water phase instead of air. An advantageous characteristic of EtOH is its rapid biodegradation rate in water; unlike MTBE or TMP, which degrade slowly. As a consequence, EtOH does not pose a significant risk to water resources. Preliminary health-protective limits for EtOH in drinking water suggest that routine releases to the environment will not result in levels that threaten human health.
MTBE catalyst shows increased conversion in commercial unit
Not Available
Rising demand for methyl tertiary butyl ether (MTBE) has spawned interest in finding a cost-effective means of increasing production from existing units. A commercial trial of an improved MTBE catalyst was conducted recently at Lyondell Petrochemical Co.'s Channelview, Tex., plant. The new catalyst called Amberlyst 35 Wet, enhanced oxygenate production in the Lyondell trial. The new catalyst changes the activity coefficients of at least one of the components of the MTBE reaction, resulting in higher equilibrium conversion relative to its first-generation counterpart. Key catalyst properties are: particle size, 0.4--1.25 mm; Apparent density, 0.82 g/ml; Surface area, 44 sq m/g; Moisture content, 56%; Concentration of acid sites, 1.9 meq/ml (5.4 meq/g); Porosity, 0.35 cc/g; and Average pore diameter, 300 [angstrom]. Suggested operating conditions are: maximum temperature, 284 F (140 C); minimum bed depth, 24 in. (0.61 m); and liquid hourly space velocity (LHSV), 1--5 hr[sup [minus]1].
High-resolution NMR process analyzer for oxygenates in gasoline
Skloss, T.W.; Kim, A.J.; Haw, J.F. (Texas A M Univ., College Station, TX (United States))
We report a high-resolution 42-MHz[sup 1]HFT-NMR instrument that is suitable for use as a process analyzer and demonstrate its use in the determination of methyl tert-butyl ether (MTBE) in a flowing stream of gasoline. This spectrometer is based on a 55-kg permanent magnet with essentially no fringe field. A spectral resolution of 3 Hz was typically obtained for spinning samples, and this performance was only slightly degraded with flowing samples. We report a procedure for magnet drift compensation using a software procedure rather than a field-frequency lock channel. This procedure allowed signal averaging without loss of resolution. Regulatory changes to be implemented in the near future have created a need for the development of methods for the determination of MTBE and other oxygenates in reformulated gasolines. Existing methods employing gas chromatography are not fast enough for process control of a gasoline blender and suffer from other limitations. This study demonstrates that process analysis NMR is well-suited to the determination of MTBE in a simulated gasoline blender. The detection limit of 0.5 vol % MTBE was obtained with a measurement time of 1 min. The absolute standard deviation of independent determinations was 0.17% when the MTBE concentration was 10%, a nominal value. Preliminary results also suggest that the method may be applicable to gasolines containing mixtures of oxygenate additives as well as the measurement of aromatic and olefinic hydrogens. 33 refs., 9 figs.
Remediation of MTBE in groundwater: A case where pump-and-treat works
Bass, D.H.; Riley, B. [Groundwater Technology, Inc., Norwood, MA (United States); Farrell, T. [Groundwater Technology, Inc., Trenton, NJ (United States)
Two case studies are discussed in which groundwater pumping reduced levels of dissolved methyl tertiary butyl ether (MTBE) in groundwater by more than two orders of magnitude, in some cases to below detection limits. MTBE contamination in groundwater is becoming an important issue due to the increasing prevalence and regulation of this gasoline additive. In addition, MTBE is more mobile in groundwater than most hydrocarbons, so it is usually the first gasoline constituent to reach sensitive receptors. Since its Henry`s constant is low, in situ removal of MTBE from groundwater by air sparging is slow, and MTBE does not rapidly degrade, either biologically or abiotically. Therefore, groundwater pumping is usually employed to contain and collect MTBE-contaminated groundwater. Pumping groundwater can reduce MME levels to below detection limits within a few years, because MTBE in the subsurface is found mostly dissolved in groundwater. In contrast, the more hydrophobic gasoline hydrocarbons exist mostly in pockets of separate phase material and adsorbed to soil particles and dissolve slowly in groundwater. Hydrocarbon concentrations are rarely reduced to closure levels within a reasonable time frame by pumping. Sites in eastern Massachusetts and southern New Jersey, where groundwater was contaminated with MTBE due to releases of unleaded gasoline from underground storage tanks, are discussed. At these sites, average MTBE levels were reduced by two to three orders of magnitude, from several ppm or more to less than 10 ppb within three years by pumping groundwater at 10 to 30 gpm.
Factors influencing biological treatment of MTBE contaminated ground water
Stringfellow, William T.; Hines Jr., Robert D.; Cockrum, Dirk K.; Kilkenny, Scott T.
Methyl tert-butyl ether (MTBE) contamination has complicated the remediation of gasoline contaminated sites. Many sites are using biological processes for ground water treatment and would like to apply the same technology to MTBE. However, the efficiency and reliability of MTBE biological treatment is not well documented. The objective of this study was to examine the operational and environmental variables influencing MTBE biotreatment. A fluidized bed reactor was installed at a fuel transfer station and used to treat ground water contaminated with MTBE and gasoline hydrocarbons. A complete set of chemical and operational data was collected during this study and a statistical approach was used to determine what variables were influencing MTBE treatment efficiency. It was found that MTBE treatment was more sensitive to up-set than gasoline hydrocarbon treatment. Events, such as excess iron accumulation, inhibited MTBE treatment, but not hydrocarbon treatment. Multiple regression analysis identified biomass accumulation and temperature as the most important variables controlling the efficiency of MTBE treatment. The influent concentration and loading of hydrocarbons, but not MTBE, also impacted MTBE treatment efficiency. The results of this study suggest guidelines for improving MTBE treatment. Long cell retention times in the reactor are necessary for maintaining MTBE treatment. The onset of nitrification only occurs when long cell retention times have been reached and can be used as an indicator in fixed film reactors that conditions favorable to MTBE treatment exist. Conversely, if the reactor can not nitrify, it is unlikely to have stable MTBE treatment.
Morris, G.D.L.; Cornitius, T.
After several months of drifting lower in line with declining autumn gasoline prices, tabs for methyl tert-butyl ether (MTBE) have turned around. There has been no big demand surge, but consumers and traders are beginning to build up inventories in advance of a series of midwinter shutdowns and turnarounds by producers. Spot prices, which dropped as low as 75 cts/gal, have rebounded to 90 cts/gal fob. Eager for a positive glimmer, methanol producers posted a 3-cts/gal increase in contract prices this month. It marks the first upward idea since February. In that time contract prices have dropped 75% from $1.55/gal to 39 cts/gal. A hard winter has hit early in much of the US sending natural gas prices up sharply. At the same time, formaldehyde and acetic acid markets remain firm, and with MTBE rebounding, methanol producers feel entitled to a piece of the action. {open_quotes}I don`t buy into this claim that MTBE demand is up and I don`t think producers can justify even a 3-cts/gal increase,{close_quotes} says one. {open_quotes}There is nothing in the economy to warrant a run-up. Housing starts are weaker, and demand is down at least 80,000 bbl/day with the MTBE shutdown.{close_quotes}
High-temperature ignition of propane with MTBE as an additive: Shock-tube experiments and modeling
Gray, J.A. (Sandia National Labs., Livermore, CA (United States)); Westbrook, C.K. (Lawrence Livermore National Lab., CA (United States))
Ignition of propane has been studied in a shock tube and by computational modeling to determine the effect of methyl tert-butyl ether (MTBE) as a fuel additive. MTBE and isobutene were added to amounts up to 25% of the fuel to propane-oxygen-argon mixtures to shock-tube experiments covering a range of temperatures between 1450 and 1800 K. Ignition delays were measured from chemiluminescence at 432 nm due to excited CH radicals. The temperature dependence of the ignition rates was analyzed to yield Arrhenium parameters of E{sub a}{sup {minus}}40 kcal/mol and log(A) {sup {minus}}9.0 sec{sup {minus}1} for the overall reaction. Reactions involving MTBE and its decomposition products were combined with an established propane mechanism in a numerical model to describe the kinetic interaction of this additive with a typical hydrocarbon fuel. The experiments and the kinetic model both show that MTBE and isobutene retard propane ignition with nearly equal efficiency. The kinetic model demonstrates that isobutene kinetics are responsible for inhibition by both MTBE and isobutene, and the specific elementary reactions which produce this behavior are identified. 19 refs., 1 fig., 3 tabs.
Heterogeneous models of tubular reactors packed with ion-exchange resins: Simulation of the MTBE synthesis
Quinta Ferreira, R.M.; Almeida-Costa, C.A. [Univ. of Coimbra (Portugal). Dept. of Chemical Engineering; Rodrigues, A.E. [Univ. of Porto (Portugal). Dept. of Chemical Engineering
The study of behavior of fixed-bed reactors using ion-exchange resins as catalysts was carried out by making use of a complete bidimensional heterogeneous model for the reactor, which included the resistances inside the ion-exchange resin particles, considered with a macroreticular structure. The active sites were located inside the gel phase of the resin, represented by microspheres, and on the macropores walls. The overall efficiency of such heterogeneous catalyst particles was defined by the macroeffectiveness and microeffectiveness factors accounting for the process behavior on the macropores and inside the microspheres. The synthesis of methyl tert-butyl ether, MTBE, a liquid-phase reversible exothermic reaction between methanol and isobutene, was considered as a reference case. This system was studied in the temperature range of 313--338 K, and the effect of the thermodynamic equilibrium conditions was examined. The results predicted by the complete heterogeneous model were compared with those obtained with the simple pseudohomogeneous model, which revealed higher hot spots. Moreover, a comparison between bidimensional and unidimensional models was also performed. The orthogonal collocation method was used for the discretization of the differential equations inside the catalyst particles, which were reduced from three (corresponding to the three mass balances for the three compounds, isobutene, methanol, and MTBE) to only one differential equation, by using the concept of the generalized variable.
Add MTBE unit ahead of alkylation
Masters, K.R.; Prohaska, E.A.
Approximately three years ago, the people at Diamond Shamrock's Sunray, Texas, refinery recognized a growing demand for high octane super premium unleaded gasoline in their regional marketing area. It was apparent that they would need to change their processing scheme to meet this growing demand. After investigating several options, they decided to install an MTBE (methyl tert-butyl ether) unit upstream of their existing sulfuric acid (H/sub 2/SO/sub 4/) aklylation unit. The new unit would process olefin feed before it entered the alkylation unit. The MTBE unit was expected to improve Diamond Shamrock's gasoline pool in two ways. First, the MTBE would be an additional high octane blending stock for the gasoline pool. Second, the MTBE unit would improve the quality of the olefin stream going to the alkylation unit. Diamond Shamrock brought their MTBE unit onstream in December, 1985. The results of the combined operation exceeded expectations, producing alkylate in excess of 98 RON (Research octane number) and MTBE of 118 RON. These components significantly upgraded the refinery's capability to produce a super premium unleaded gasoline.
Catalyst and process development for synthesis gas conversion to isobutylene. Quarterly report, October 1, 1993--December 31, 1993
Anthony, R.G.; Akgerman, A.
The objectives of this project are to develop a new catalyst; the kinetics for this catalyst; reactor models for trickle bed, slurry and fixed bed reactors; and to simulate the performance of fixed bed trickle flow reactors, slurry flow reactors, and fixed bed gas phase reactors for conversion of a hydrogen lean synthesis gas to isobutylene. A hydrogen-lean synthesis gas with a ratio of H{sub 2}/CO of 0.5 to 1.0 is produced from the gasification of coal, lignite, or biomass. Isobutylene is a key reactant in the synthesis of methyl tertiary butyl ether (MTBE) and of isooctanes. MTBE and isooctanes are high octane fuels used to blend with low octane gasolines to raise the octane number required for modern automobiles. The production of these two key octane boosters is limited by the supply of isobutylene. MTBE, when used as an octane enhancer, also decreases the amount of pollutants emitted from the exhaust of an automobile engine.
Study downplays health concerns
Stringer, J.
A government-funded study has concluded that reformulated gasoline containing methyl tert-butyl ether (MTBE) does not increase short-term health risks when compared with gasoline that does not contain the additive. The study, performed by the Health Effects Institute (Cambridge, MA), compared data from dozens of animal, human, and epidemiological studies of health effects linked to oxygenates, including MTBE and ethanol, but did not find enough evidence to warrant an immediate reduction in oxygenate use. However, the study did recommend that additional research be conducted on possible health consequences associated with the gasoline additives, including neurotoxic effects, if oxygenates continue to be used long term. Oxygenates have been used in gasoline since 1992, when EPA mandated that several municipalities use MTBE or other oxygenates in reformulated gasoline to reduce carbon monoxide emissions and meet Clean Air Act requirements. Shortly after the program began, residents in areas where the oxygenates were used complained of nausea, headaches, and dizziness. The institute says the study--funded by EPA and the Centers for Disease Control--will be used for a broader review of gasoline oxygenates by the White House Office of Science and Technology Policy.
Characterization of the Cobalamin and Fep Operons in Methylobium petrolphilum PM1
Ewing, J
The bacterium Methylobium petroleophilum PM1 is economically important due to its ability to degrade methyl tert-butyl ether (MTBE), a fuel additive. Because PM1 is a representative of all MTBE degraders, it is important to understand the transport pathways critical for the organism to survive in its particular environment. In this study, the cobalamin pathway and select iron transport genes will be characterized to help further understand all metabolic pathways in PM1. PM1 contains a total of four cobalamin operons. A single operon is located on the chromosome. Located on the megaplasmid are two tandem repeats of cob operons and a very close representative of the cob operon located on the chromosome. The fep operon, an iron transport mechanism, lies within the multiple copies of the cob operon. The cob operon and the fep operon appear to be unrelated except for a shared need for the T-on-B-dependent energy transduction complex to assist the operons in moving large molecules across the outer membrane of the cell. A genomic study of the cob and the fep operons with that of phylogenetically related organisms helped to confirm the identity of the cob and fep operons and to represent the pathways. More study of the pathways should be done to find the relationship that positions the two seemingly unrelated cob and fep genes together in what appears to be one operon.
Advanced quadrupole ion trap instrumentation for low level vehicle emissions measurements. CRADA final report for number ORNL93-0238
McLuckey, S.A.; Buchanan, M.V.; Asano, K.G.; Hart, K.J.; Goeringer, D.E. [Oak Ridge National Lab., TN (United States); Dearth, M.A. [Ford Motor Co., Dearborn, MI (United States). Environmental Research Consortium
Quadrupole ion trap mass spectrometry has been evaluated for its potential use in vehicle emissions measurements in vehicle test facilities as an analyzer for the top 15 compounds contributing to smog generation. A variety of ionization methods were explored including ion trap in situ chemical ionization, atmospheric sampling glow discharge ionization, and nitric oxide chemical ionization in a glow discharge ionization source coupled with anion trap mass spectrometer. Emphasis was placed on the determination of hydrocarbons and oxygenated hydrocarbons at parts per million to parts per billion levels. Ion trap in situ water chemical ionization and atmospheric sampling glow discharge ionization were both shown to be amenable to the analysis of arenes, alcohols, aldehydes and, to some degree, alkenes. Atmospheric sampling glow discharge also generated molecular ions of methyl-t-butyl ether (MTBE). Neither of these ionization methods, however, were found to generate diagnostic ions for the alkanes. Nitric oxide chemical ionization, on the other hand, was found to yield diagnostic ions for alkanes, alkenes, arenes, alcohols, aldehydes, and MTBE. The ability to measure a variety of hydrocarbons present at roughly 15 parts per billion at measurement rates of 3 Hz was demonstrated. These results have demonstrated that the ion trap has an excellent combination of sensitivity, specificity, speed, and flexibility with respect to the technical requirements of the top 15 analyzer.
Selecting activated carbon for water and wastewater treatability studies
Zhang, W.; Chang, Q.G.; Liu, W.D.; Li, B.J.; Jiang, W.X.; Fu, L.J.; Ying, W.C. [East China University of Chemical Technology, Shanghai (China)
A series of follow-up investigations were performed to produce data for improving the four-indicator carbon selection method that we developed to identify high-potential activated carbons effective for removing specific organic water pollutants. The carbon's pore structure and surface chemistry are dependent on the raw material and the activation process. Coconut carbons have relatively more small pores than large pores; coal and apricot nutshell/walnut shell fruit carbons have the desirable pore structures for removing adsorbates of all sizes. Chemical activation, excessive activation, and/or thermal reactivation enlarge small pores, resulting in reduced phenol number and higher tannic acid number. Activated carbon's phenol, iodine, methylene blue, and tannic acid numbers are convenient indicators of its surface area and pore volume of pore diameters < 10, 10-15, 15-28, and > 28 angstrom, respectively. The phenol number of a carbon is also a good indicator of its surface acidity of oxygen-containing organic functional groups that affect the adsorptive capacity for aromatic and other small polar organics. The tannic acid number is an indicator of carbon's capacity for large, high-molecular-weight natural organic precursors of disinfection by-products in water treatment. The experimental results for removing nitrobenzene, methyl-tert-butyl ether, 4,4-bisphenol, humic acid, and the organic constituents of a biologically treated coking-plant effluent have demonstrated the effectiveness of this capacity-indicator-based method of carbon selection.
Role of alkyl alcohol on viscosity of silica-based chemical gels for decontamination of highly radioactive nuclear facilities
Choi, B. S.; Yoon, S. B.; Jung, C. H.; Lee, K. W.; Moon, J. K. [Div. of Decontamination and Decommissioning Technology Development, Korea Atomic Energy Research Inst., Daedeok-daero 989-111, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of)
Silica-based chemical gel for the decontamination of nuclear facilities was prepared by using fumed silica as a viscosifier, a 0.5 M Ce (IV) solution dissolved in concentrated nitric acid as a chemical decontamination agent, and tripropylene glycol butyl ether (TPGBE) as a co-viscosifier. A new effective strategy for the preparation of the chemical gel was investigated by introducing the alkyl alcohols as organic solvents to effectively dissolve the co-viscosifier. The mixture solution of the co-viscosifier and alkyl alcohols was more effective in the control of viscosity than that of the co-viscosifier only in gel. Here, the alkyl alcohols played a key role as an effective dissolution solvent for the co-viscosifier in the preparation of the chemical gel, resulting in a reducing of the amount of the co-viscosifier and gel time compared with that of the chemical gel prepared without the alkyl alcohols. It was considered that the alkyl alcohols contributed to the effective dissolution of the co-viscosifier as well as the homogeneous mixing in the formation of the gel, while the co-viscosifier in an aqueous media of the chemical decontamination agent solution showed a lower solubility. The decontamination efficiency of the chemical gels prepared in this work using a multi-channel analyzer (MCA) showed a high decontamination efficiency of over ca. 94% and ca. 92% for Co-60 and Cs-137 contaminated on surface of the stainless steel 304, respectively. (authors)
Catalytic Consequences of Acid Strength in the Conversion of...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Consequences of Acid Strength in the Conversion of Methanol to Dimethyl Ether. Catalytic Consequences of Acid Strength in the Conversion of Methanol to Dimethyl Ether. Abstract:...
Inorg. Chem. 1993, 32, 2001-2004 2001 Ruthenium Ammine/Crown Ether Interactions in Solution: Effects of Modification of both Guest
, K.; Kurihara, H. Polyhedron 1991, IO,1139. (5) (a) Strzelbicki,J.;Charewicz, W.A.; Liu,Y.;Bartsch, R, D. J. J. Chem. SOC.Dalton Trans. 1983, 607. (g) Young,C. W.; Bartsch, R. A,;Holwerda, R. A. Inorg
Structure of n-Butyllithium in Mixtures of Ethers and Diamines: Influence of Mixed Solvation on 1,2-Additions to
Collum, David B.
-8 Moreover, TMCDA is a stronger ligand than TMEDA by 0.5 kcal/mol.6,9 (This statement is laced.; Spero, D. M. Org. Prep. Proced. Int. 2000, 32, 205. (3) The first report of a polyamine
Osaka, Ichie
shock protein 60 (hsp60), inclusion membrane proteins such as various Inc proteins, and effector proteins of the type III secretion system (T3SS) that are secreted into host cytosol. Vaginal Microbicide Although immunization would be an ideal strategy...-negative infection can lead to septic shock [139]. LPS is also recognized for the essential roles it plays in the pathogenesis and survival of Gram-negative bacteria. LPS contributes greatly to the structural integrity and stability of the outer membrane...
Bisphenol A Diglycidyl Ether Induces Adipogenic Differentiation of Multipotent Stromal Stem Cells through a Peroxisome Proliferator-Activated Receptor Gamma-Independent Mechanism
Food contamination from epoxy resins and organosols used asG. 1981. Metabolism of the epoxy resin component 2,2-bis[4-(in the manufacture of epoxy resins, paints, and as a coating
Sulfobutyl Ether b-Cyclodextrin (SBE-b-CD) in Eyedrops Improves the Tolerability of a Topically Applied Pilocarpine Prodrug in Rabbits
Stella, Valentino J.; Jä rvinen, Tomi; Jä rvinen, Kristina; Thompson, Diame; Urtti, Arto
,O'-dipropionyl-(1,4-xylylene) bispilocarpate, in albino rabbits were studied. Compared to the commercial pilocarpine eyedrop solution (163 mM, equivalent to 3.4% pilocarpine), 12 - 24 mM pilocarpine prodrug solutions (equivalent to 0.5 - 1.0% pilocarpine...
Center for Water Resources Annual Technical Report
of Ethanol on Anaerobic Production of Tert-Butyl Alcohol (TBA) from MTBE in Groundwater Kate M. Scow, Douglas
Fighting Against the Invisible: The new weapons against chemical warfare
Nguyen, Leana
Internation Institute of synthetic rubber producers (IISRP).butyl rubber is a synthetic rubber that is imper- meable to
N-(N-[2-(3,5-Difluorophenyl)acetyl]-(S)-alanyl)-(S)-phenylglycine tert-butyl ester (DAPT): an inhibitor of ?-secretase, revealing fine electronic and hydrogen-bonding features
Czerwinski, Andrzej; Valenzuela, Francisco [Peptides International Inc., 11621 Electron Drive, Louisville, KY 40299 (United States); Afonine, Pavel [Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720 (United States); Dauter, Miroslawa, E-mail: firstname.lastname@example.com [Basic Research Program, SAIC-Frederick Inc., Synchrotron Radiation Research Section, MCL, NCI, Argonne National Laboratory, Biosciences Division, Building 202, Argonne, IL 60439 (United States); Dauter, Zbigniew [Synchrotron Radiation Research Section, MCL, NCI, Argonne National Laboratory, Biosciences Division, Building 202, Argonne, IL 60439 (United States); Peptides International Inc., 11621 Electron Drive, Louisville, KY 40299 (United States)
The title compound, C{sub 23}H{sub 26}F{sub 2}N{sub 2}O{sub 4}, is a dipeptidic inhibitor of ?-secretase, one of the enzymes involved in Alzheimer's dis@@ease. The mol@@ecule adopts a compact conformation, without intra@@molecular hydrogen bonds. In the crystal structure, one of the amide N atoms forms the only inter@@molecular N—H?O hydrogen bond; the second amide N atom does not form hydrogen bonds. High-resolution synchrotron diffraction data permitted the unequivocal location and refinement without restraints of all H atoms, and the identification of the characteristic shift of the amide H atom engaged in the hydrogen bond from its ideal position, resulting in a more linear hydrogen bond. Significant residual densities for bonding electrons were revealed after the usual SHELXL refinement, and modeling of these features as additional inter@@atomic scatterers (IAS) using the program PHENIX led to a significant decrease in the R factor from 0.0411 to 0.0325 and diminished the r.m.s. deviation level of noise in the final difference Fourier map from 0.063 to 0.037 e Ĺ{sup ?3}.
Measurements of the effect of a magnetic field on the transport of linear momentum in nitrogen
Larchez, Mark Edward
torgue in the same direction. A torque in the direction opposite to this is produced by methane, et'nane, propane, butane, isobutane, 7 hydrogen, nydrogen deuteride, and ceuterium, No torque is shown by helium, argon, xenon, water vapor, carbon...
Flammability Characteristics of Hydrogen and Its Mixtures with Light Hydrocarbons at Atmospheric and Sub-atmospheric Pressures
Le, Thuy Minh Hai
/vapor. This research focuses on the flammability limits of hydrogen and its binary mixtures with light hydrocarbons (methane, ethane, n-butane, and ethylene) at sub-atmospheric pressures. The flammability limits of hydrogen, light hydrocarbons, and binary mixtures...
942 Inorganic Chemistry, Vol. 10, No. 5, 1971 solid (mp 43" with slight decomposition), which is sensitive to
Bodner, George M.
is sensitive to air and water. I t is soluble in carbon tetrachloride, trichloro- fluoromethane, and benzene but insoluble in butane. The infrared spectrum (4000-200 cm-l) in carbon tetrachloride showed the following
Transient behaviour of dense catalytic membranes based on Cu-and Co-doped Bi4V2O11 (BIMEVOX) in the oxidation of propene and propane
Paris-Sud XI, Université de
adsorbed oxygens which mostly lead to the formation of carbon oxides [1]. In usual fixed or fluidised bed. The oxidation of n- butane to maleic anhydride in a circulating fluid bed reactor was the first industrial
"Nanocrystal bilayer for tandem catalysis"
Yamada, Yusuke
Hydrogenolysis of Ethane, Propane, n-Butane and iso-Butanethe Hydroformylation of Propane over Silica-supported Groupproduct and small amount of propane, which is likely to be
Feasibility of reconstructing paleoatmospheric records of selected alkanes, methyl halides, and sulfur gases from Greenland ice cores
Aydin, M.; Williams, M. B; Saltzman, E. S
study of ethane and propane oxidation in the tropo- sphere,alkanes (ethane, C 2 H 6 ; propane, C 3 H 8 ; n-butane, n-Cfluid contamination. 4.1.2. Propane [ 24 ] Propane levels in
Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]
natural gas is subject to a tax of 0.16 per diesel gallon equivalent. Compressed natural gas, butane, and propane are subject to a tax of 0.16 per gasoline gallon...
Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]
gallon equivalent for liquefied natural gas and 0.11 per gasoline gallon equivalent for compressed natural gas, butane, or propane. (Reference Indiana Code 6-6-2.5 and 6-6-4.1-1...
Theoretical Simulation of n-Alkane Cracking on Zeolites Joseph A. Swisher,,|
Bell, Alexis
calculations for propane and butane cracking on MFI reveal that significantly better agreement between reactions, as well as the distribution of the products formed from a specified set of reactants. Impressive
Embedding parameters in ab initio theory to develop well-controlled approximations based on molecular similarity
Yaron, David
is explored by training such a model on data for ethane and testing the resulting model on methane, propane and butane. The electronic distribution of the molecules is varied by placing them in strong electrostatic
Hydrogen Storage -Overview George Thomas, Hydrogen Consultant to SNL*
aspects of hydrogen utilization. production distribution utilization How do we achieve safe, efficient Forecourt storage (refueling stations) requirements being developed (IHIG) Distribution storage (delivery 75 100 125 hydrogen m ethane ethane propane butane pentane hexane heptane octane (gasoline) cetane
Farritor, Shane
% by volumevolume Propylene, Propane, Butane, Ethylene Praxair Distribution Inc., Quality Department .Copyright by Pam HendershotNebraska Lincoln Pam Hendershot Praxair Distribution Inc. Praxair Distribution Inc Praxair Distribution Inc., Quality Department .Copyright © 2000, Praxair Technology, Inc. All rights
T h e o p e n a c c e s s j o u r n a l f o r p h y s i c s New Journal of Physics
Gribakin, Gleb
methane and its fluoro-substitutes, ethane, propane, butane and benzene are presented. The annihilation -spectra characterise the momentum distribution of the electronpositron pair at the instant
Nitrogen limiation and nitrogen fixation during alkane biodegradation in a sandy soil
Toccalino, P.L.; Johnson, R.L.; Boone, D.R. (Oregon Graduate Institute of Science Technology, Portland, OR (United States))
Leaking underground storage tanks are a significant source of petroleum hydrocarbon contamination in soils and ground water. Hydrocarbon biodegradation studies have been conducted in both ground water and topsoil regions, but few studies have been done on the unsaturated zone between these two. This study examines the effects of Nitrogen on propane and butane biodegradiations in an unsaturated sandy soil. Results indicate that nitrogen additions initially stimulated both propane and butane oxidizing organisms in the soil, but that propane-amended soil became N limited whereas butane-amended soil eventually overcame its N limitations by fixing Nitrogen and that nitrogen fixing organisms grew in butane amended but not in propane amended soil. 27 refs., 6 figs.
Anzahl von Strukturisomeren der Alkane ???? und Sascha Kurz??
Kurz, Sascha
_____________________________________________________________________________ Zusammenfassung Das Ph"anomen der Strukturisomerie wird anhand der Klasse der Alkane erkl"art. * *Auf ei- nem f || 9,5 2-Methyl-butan || -158.6 || 27.9 n-Pentan || -129
(2/94)(1,2,8/95)(6,7/97)(10/98)(1,9-11/99) Neuman Chapter 2 Alkanes and Cycloalkanes
Reed, Christopher A.
Conformations of Other Alkanes (2.4C) 2-30 Propane Butane Torsional Strain and Steric Strain (2.4D) 2. Conjugation, Electronic Effects, Carbonyl Groups 12. Conjugated and Aromatic Molecules 13. Carbonyl Compounds
Atmos. Chem. Phys., 14, 1287112882, 2014 www.atmos-chem-phys.net/14/12871/2014/
Pierce, Jeffrey
-butane that are associated with fuel evapora- tion, an insignificant source for CO2. To better characterise the traffic is likely the obsolete feature of the VOCs speciation matrix of the inventory that has not been updated
Industrial Fuel Switching - Emerging NGL Opportunities
Cascone, R.
Removing butanes and pentanes from gasoline to meet local and seasonal regulatory limitations on volatility requires US refiners to make up the lost octane with higher cost alternative components, and challenges them to either: store the liquids...
Flammability Characteristics of Hydrogen and Its Mixtures with Light Hydrocarbons at Atmospheric and Sub-atmospheric Pressures
Le, Thuy Minh Hai
/vapor. This research focuses on the flammability limits of hydrogen and its binary mixtures with light hydrocarbons (methane, ethane, n-butane, and ethylene) at sub-atmospheric pressures. The flammability limits of hydrogen, light hydrocarbons, and binary mixtures...
AME 513 Assigned: Tuesday 10/2/2012 Problem Set #2 Due Monday 10/15/2012 at 4:30 pm in the drop box in
: 4.20 (Partial equilibrium) 5.6 (Beta scission) 5.7 (Butane oxidation) 5.8 (Reduced mechanisms) Other. (a) From this information, estimate the pre-exponential factor Z and activation energy Ea. (b
Phase Equilibria Bibliography Updated 6/04 PUBLICATIONS (REFEREED)
Howat, Colin S. "Chip"
.G., and Howat, C.S., 1990. Vapor-Liquid Phase Equilibria and Molar Volumes of the Butadiene-Acetonitrile System-Butane and Acetonitrile, 1-Butene and Acetonitrile and 1,3-Butadiene and Acetonitrile. 7th International Congress
U.S. Energy Information Administration (EIA) - Source
Gasoline and Diesel Fuel Update (EIA)
include smaller amounts of butane and ethane. Currently, most U.S. exports of LPG go to Latin America, where LPG is used for heating and cooking. International implications The...