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Separation of Carbon Dioxide from Natural Gas by Matrimid-Based Mixed Matrix Membranes
|Gas Processing Journal
|نوع مقاله: Original Article
|شناسه دیجیتال (DOI): 10.22108/gpj.2017.102840.1009
|Akbar Samadi؛ Amir Hosein Navarchian
|Department of Engineering, Faculty of Chemical Engineering, University of Isfahan, Isfahan, Iran
|Spherical MgO nanoparticles and Flake-like clay minerals modified with polyaniline (PAni) are applied in Matrimid in order to fabricate mixed matrix membranes (MMMs) having improved gas separation performance. The CO2 permeability, CO2/CH4 selectivity and CO2-induced plasticization pressure of MMMs are assessed at 4-30 bar feed pressure. The chemical structure, morphology and thermal properties of MMMs are analyzed by Fourier transform infrared equipped with attenuated total reflection (FTIR-ATR), X-ray diffraction, field emission scanning electron microscopy (FESEM) and differential scanning calorimetry/thermogravimetric analyses. Crater-like morphology is seen for MMMs by FESEM tests Physical interaction of Matrimid with MgO and PAni, confirmed by FTIR-ATR, helps better distribution of both the fillers in the polymer matrix. Mechanistical analysis of gas sorption and diffusion terms reveals that PAni/clay (PC) enhances gas permeability by controlling diffusivity paths, while MgO nanoparticles improves both gas solubility and diffusivity. The permeability tests reveal that the sample PC5M5 with 5 wt% PC and 5 wt% MgO, has the best gas separation properties. High pressure tests reveal that this sample can enhance plasticization pressure and CO2 permeability as well by 76% and 200%, respectively; resulting in 425% enhancement in MMMs capacity in natural gas sweetening.
تازه های تحقیق
|CO2 Removal؛ mixed matrix membrane؛ Matrimid؛ plasticization
|اصل مقاله
With respect to the expected growth in the demand for natural gas, it is necessary to upgrade low-quality natural gas by gas sweetening processes in order to decrease CO2 and H2S content thereof (Hao, Rice, & Stern, 2002). In case of CO2, it causes corrosion in presence of any moisture and increases the cost of gas transportation (Colin A. Scholes, Stevens, & Kentish, 2012). In addition, the separation of CO2 from industrial stack gases, is vital from the environmental point of view(Bhide, Voskericyan, & Stern, 1998). Nowadays, MMMs are the subjects of many studies conducted in natural gas sweetening field because they combine the polymer advantages of processability, flexibility and availability with good separation property as well as the thermal/mechanical stability of inorganic fillers. Among many existing polymers studied in gas separations, the focus is on polyimides due to their high gas permeability, high intrinsic permselectivity, appropriate mechanical strength and chemical stability as compared with other conventional membranes (Sridhar, Veerapur, Patil, Gudasi, & Aminabhavi, 2007). Matrimid® is a thermoplastic polyimide, widely applied as a commercial grade for gas separation processes (Tin et al., 2003). This polymer, is plasticized by CO2 at pressures around 10 bar at room temperature leading to an increase in permeabilities of all separating gases, thus, deterioration of selectivity. When the CO2 concentration is high enough to interact with polymer chains, it can increase the segmental mobility and the free volumes within the macromolecules (Bos, Pünt, Strathmann, & Wessling, 2001). Plasticization can be suppressed by cross‐linking, polymer blending and applying inorganic fillers in polymer matrix, that is, fabrication of MMMs (Dong, Li, & Chen, 2011; Gh & Navarchian, 2016; Hosseini, Peng, & Chung, 2010; Hosseini, Teoh, & Chung, 2008; Ismail & Lorna, 2002; Perez, Balkus Jr, Ferraris, & Musselman, 2014; Shahid & Nijmeijer, 2014b; Su et al., 1997; Xiao, Low, Hosseini, Chung, & Paul, 2009).
Various fillers like zeolites (Shahid & Nijmeijer, 2014a; Y. Zhang, Balkus Jr, Musselman, & Ferraris, 2008), silica (Ahn, Chung, Pinnau, & Guiver, 2008), alumina (Tena et al., 2010), clay (Bhole, Wanjale, Kharul, & Jog, 2007; Defontaine et al., 2010; Gh & Navarchian, 2016) and metal oxides (Hosseini, Li, Chung, & Liu, 2007) are applied in MMMs for gas separation. These fillers are appropriate candidates in overcoming the plasticization phenomenon and the permselectivity limitations of polymeric membranes for gas separation as presented by Robeson upper bound (Noble, 2011; Robeson, 2008). They may control the chain mobility by mutual interactions that prevent plasticization of polymer matrix at high feed pressures (Ismail & Lorna, 2002). The tortuosity of diffusion path increases by applying these fillers into the polymer matrix that improve the selectivity in the favor of smaller penetrant (Bertelle, Gupta, Roizard, Vallières, & Favre, 2006). This is due to the fact that the selectivity of polymers at temperatures below their glass transition temperature (Tg) is mainly dominated by diffusivity term (Yampolskii, Pinnau, & Freeman 2006). While the fillers, may disrupt the polymer chain packing which leads to an increase in polymer free volume and generate voids in the polymer matrix that improve permeability of gaseous penetrants (Gh & Navarchian, 2016; Hashemifard, Ismail, & Matsuura, 2011; He, Pinnau, & Morisato, 2002; Liang et al., 2012).
Several authors have assessed the effect of fillers on CO2/CH4 separation behavior of MMMs. Hashemifard et al. reported significant increase in permeability of CO2 and CH4 by applying montmorillonite clays with different types of interlayer cations to the polyetherimide matrix (Hashemifard et al., 2011). Applying montmorillonite in polyethersulfone is reported by Liang et al (2012) to increase permeability values of both CO2 and CH4 gases. They attributed this improvement mainly to extra gas transport paths produced on the polymer-clay interface (Liang et al., 2012). Montmorillonite modified by PAni was incorporated into Matrimid matrix, where, an enhanced permeability of CO2 and CH4 is observed as the small voids production in the polymer/clay interfaces (Gh & Navarchian, 2016). The plasticization pressure is postponed to higher pressures when PC particles are applied.
Gas permeability in dense membrane is subject to solution-diffusion mechanism(Baker, 2004). Although, the selectivity of glassy polymers at temperatures below Tg is influenced mainly by the fillers with high aspect ratio like montmorillonite, that increase the diffusion path (Yampolskii et al., 2006), it is suggested that applying fillers with special functional groups, like magnesium oxide (MgO) nanoparticles with hydroxyl groups on the surface, can interact with polar gases including CO2 which would improve its solubility and gas permeability (Cong, Radosz, Towler, & Shen, 2007; Hosseini et al., 2007; Hu et al., 1997; Pacchioni, 1993). The polymer-particle interactions may reduce the chain mobility that results in less plasticization. It can be assumed, that applying these two kinds of fillers may enhance the permselectivity and plasticization behavior of dense membranes.
To the best of authors' knowledge, here, there exist no report suggesting simultaneous application of both modified silicate layer and MgO nanoparticles in the Matrimid matrix. In this study, two fillers with different geometry and chemical properties including flake-like PC and spherical MgO nanoparticles are applied in order to improve both permeability and selectivity of MMMs and their plasticization resistance in the CO2/CH4 separation process. Chemical structure, morphology and thermal properties of fabricated membranes are analyzed through FTIR-ATR, XRD, FESEM, DSC and TGA. The gas permeation tests are run at different pressures to evaluate permselectivity and plasticization behavior of MMMs. The effects of MgO and PC contents on the permselectivity and plasticization resistance of Matrimid membranes are assessed as well.
2. Methods and Materials
2.1. Materials
Matrimid®5218 (Hunstman LLC Corporation, Canada, CAS number 62928-02-6) and MgO nanoparticles (average size 1-5 nm, US NANO company, USA), are consumed preparation of MMMs. The TEM image of MgO nanoparticles is shown in Fig. (1-a). PC nanocomposite (Table 1) is consumed as synthesized by in-situ polymerization of aniline in the presence of Cloisite 30B®(Gh & Navarchian, 2016). The solvent, NMP is purchased from Merck Company (Germany). The purchased chemicals are consumed upon receive.
Table 1. Characteristics of PAni/clay (PC) powder used in this study(Gh & Navarchian, 2016)
c analyzedby scanning electron microscopy (Fig.. (1-b)))
Figure 1. (a) TEM image of MgO nanoparticles prepared by the manufacturer, and (b) SEM image of PC powder (Gh & Navarchian, 2016).
2.2. Membrane Fabrication
Matrimid-based membranes containing different contents of MgO (0-10 wt%) and PC (0-10 wt%) fillers are fabricated through solution casting method (Hashemifard et al., 2011; Hosseini et al., 2007). The required volumes of Matrimid and MgO are dissolved in NMP by magnetic stirring and ultrasonication in a separate manner, next, the specified mass of PC is dispersed in NMP, stirred, ultrasonicated and then mixed with Matrimid/NMP and MgO/NMP solutions, followed by further stirring, ultrasonication and filtration. The filtrate is casted in 8 cm-diameter Petri dishes and then dried completely in the oven at 120˚C for sufficient time. Finally, the films are pilled from the glass and are dried at 200˚C for 2-3 days to obtain membranes with the thickness of 60-70 microns. Fabricated samples are coded as PCxMy, where, M is the MgO, and x and y are the PC and MgO weight percents, respectively, (e.g. PC5M5 membrane contains 5 wt% of each fillers).
2.3 Membrane Characterization
There exist many techniques for characterization of fabricated MMMs
2.3.1 Fourier Transform Infrared
The chemical structure of fabricated membranes is analyzed through FTIR-ATR spectrophotometer (JASCO FT/IR-6300, Japan) equipped with attenuated total reflection (ATR) accessory at room temperature from 4000 to 400 cm−1 with a spectral resolution of 4 cm−1 and averaged over 32 scans.
2.3.2 X-Ray Diffraction
The microstructures of membranes are analyzed through XRD technique where a Bruker diffractometer (D8 ADVANCE, Germany) at the scan range of 5˚-80˚ is applied.
2.3.3 Thermal Analysis
A simultaneous TGA/DSC system (STA 449F3 Jupiter, Netzsch, Germany) with a silicon carbide furnace is applied to assess the thermal properties of fabricated membranes. The samples of 5-10 mg weight are heated from 60 to 540°C at 10°C/min rate in the N2 atmosphere. The Netzsch Proteus Thermal Analysis software is applied for DSC and TGA data analysis.
2.3.4 Field Emission Scanning Electron Microscopy
FESEM (ZEISS SUPRA 35VP, Germany) is applied in analyzing the MMMs morphology. The samples are frozen and fractured in liquid nitrogen in order to monitor the membrane cross-section. The fractured samples are mounted on carbon tape masked on stainless steel stand and sputter-coated with 15 nm of gold prior to FESEM analysis.
2.4 Gas Permeability Tests
Gas permeability of all fabricated membranes are measured through a variable-pressure constant-volume apparatus (Model NM1390, Iran) by the following equation (Chung, Chan, Wang, Lu, & He, 2003):
where PA is the permeability coefficient of the membrane to gas A in Barrer (1 Barrer= 10-10 cm3(STP).cm/cm2.s.cmHg), V is the volume of the downstream chamber (12 cm3 ± 0.002 cm3), A is the effective area of the film (17.1 cm2 ± 0.0014 cm2), L is the thickness of the membrane (0.007 cm ± 0.0001 cm), T is the absolute temperature in measurement (298.15 K ± 0.1K), and dp/dt is the pressure rate measured at downstream chamber (mbar/s) which is calculated in of 3θ to 7θ time range (θ is the time lag in downstream pressure-time diagram)(Y. Zhang et al., 2008). The uncertainty pressure (p or p0) and time (t) measurements is ±0.1 mbar and ±0.1 sec, respectively. The relative uncertainty of permeability of gas A (PA) is less than 1.6% based on Taylor equation (Taylor, 1997).
The ideal selectivity (α) of a membrane for gas A to gas B is assessed through the following equation:
where D (cm2/sec) and S (cm3(STP)/cm3(polymer).atm) are diffusivity and solubility of penetrants in the membrane matrix. Symbols αD and αS are the diffusivity-based and solubility-based selectivity values, respectively. The permeability tests are run at 4-10 bar and 25°C for all samples. The samples are examined at 4-30 bar pressure range to determine pplast of MMMs and the effect of pressure on permeability and selectivity. The diffusion coefficient is obtained from the t-intercept, θ, of the plot p against t, as suggested by Barrer (Crank, 1975; Taveira, Mendes, & Costa, 2003):
The gas fluxes A (JA)(cm3(STP)/cm2.sec) through the membranes are calculated through the following equation (Baker, 2004):
where, ΔpA is the pressure difference across the membrane.
3. Results and Discussion
3.1. Chemical Structure
Chemical structure of pristine Matrimid, PC0M5 and PC5M5 membranes, the PC powder and MgO nanoparticles are illustrated in Fig. (2). As observed in Fig. (2-c), the peaks at 1778 cm-1 (C=O stretching of ketonic groups), 1716 cm-1 (C=O anti-symmetric stretching of imide groups), 1669 cm-1 (C=O stretching of imide groups), 1425 cm-1 (bending vibrations of aliphatic C–H bonds), and 3484 cm-1 (N-H bonds) constitute the characteristic peaks of Matrimid (Dong et al., 2011; Gh & Navarchian, 2016; Moghadam, Omidkhah, Vasheghani-Farahani, Pedram, & Dorosti, 2011; Pavia, Lampman, Kriz, & Vyvyan, 2015 ; Zhao et al., 2008). In the FTIR spectra of Matrimid-MgO and Matrimid-MgO-PC membranes and MgO nanoparticles, (Fig. (2-c_), the peak at 487-490 cm-1 is attributed to the symmetric Mg=O bond (Figs 2 (b, d and e)). The FTIR spectrum of Matrimid-PC-MgO membrane is shown in (Fig. (2-c)). The peak at 1509 cm-1 (stretching bonds of benzenoniod rings) (Kang, Neoh, Tan, Khor, & Tan, 1990; Tang, Jing, Wang, & Wang, 1988) and the peak at 1377 cm-1 (weak stretching of C-N bond in quinonoid-benzenoniod-quinonoid (QBQ) successive units) (Cao, Li, Xue, & Guo, 1986) are the characteristic transmittance of emeraldine base PC powder which are also visible in FTIR spectrum of PC powder (Fig. (2-a)) (Gh & Navarchian, 2016). The peaks of clay 30B at 400-600 cm-1 (ascribed to Si-O bending and Al-O stretching), and 1035 cm-1 (attributed to Si–O stretching) are observed in FTIR spectra of PC powder (Fig. (2-a)) and Matrimid-PC-MgO membrane (Kataria, 2005). Some shifts in Matrimid appearance peaks (the peak at 1294 cm-1 for bending of C–CO–C groups) and PC (the C-H stretching at 1302 cm-1 and stretching bonds of quinonoid rings at 1587 cm-1) may indicate the possible compatibility of these two polymers because of hydrogen bonding between carbonyl groups of Matrimid and N-H group in secondary amine functional groups of PAni (Jiang, Wang, Chung, Qiao, & Lai, 2009).
Figure 2. FTIR spectra of (a) PC powder, (b) MgO nanoparticles, (c) Matrimid membrane, (d) PC0M5 and (e) PC5M5.
3.2 Microstructure
The X-ray spectra of Matrimid membrane and corresponding MMMs are shown in Fig. (3). A broad peak observed at 2θ about 20°indicates the amorphous nature of Matrimid (Ebadi Amooghin, Omidkhah, & Kargari, 2015; Hosseini et al., 2007; Sridhar et al., 2007). Presence of this peak is often interpreted as a measure of the average intersegmental distance between the polymer chains (Aziz & Ismail, 2010; Ghosal & Freeman, 1994). Appearance of the same peak with the same broadness and strength in the XRD spectra of MMMs reveals that the incorporation of the neither of fillers in general alter the microstructure of the Matrimid matrix. As observed in Fig. (3), there exists no sharp peak representing the peaks of MgO nanoparticles. As decleared by Hosseini et al. (Hosseini et al., 2007), this is attributed to the low concentration of MgO in membrane matrix.
3.3 Thermal Properties
The DSC/TGA graphs of Matrimid-PC (sample PC5M0) and Matrimid-PC-MgO (sample PC5M5) membranes are shown in Fig. (4), where all endothermic peaks shown in DSC curves of the samples below 150°C are attributed to the evaporation of trace amount of volatile compounds including water, HCl, NH4OH, etc. with a weight loss less than 1% as seen in TGA curves (Gh & Navarchian, 2016; Narayanan et al., 2010). For both membranes, the weight loss from 150°C to 200°C (1-2%) is mainly due to the evaporation of NMP (boiling point: 202 to 204°C (Rajiv Mahajan, Burns, Schaeffer, & Koros, 2002)). The extra weight loss of about 8% at 200-455°C (for sample PC5M0) and 200-473°C (for sample PC5M5) ranges with an endothermic peak at 280-290°C is probably attributed to the loss of organic cation of 30B clay, evaporation and/or decomposition of low molecular weight polyaniline oligomers of the PC particles (Anadão, Sato, Wiebeck, & Valenzuela-Díaz, 2010; Ansari, Yadav, Cho, & Mohammad, 2013). An exothermic peak at 495-496°C is attributed to the thermal decomposition of PC and Matrimid observed in both samples. The onset of thermal decomposition of PC5M0 and PC5M5 are 455°C and 473°C which is higher than that of neat Matrimid (410°C), reported by (Perez et al., 2014). This represents an enhanced thermal stability of the membranes by incorporating PC (Anadão et al., 2010; Shi & Gan, 2007) and MgO (Moaddeb & Koros, 1997). The dispersed clay platelets probably act as barriers caused by labyrinth effect (tortuous path) (Lu, Hu, Li, Chen, & Fan, 2006) for both heat and mass transfer (Anadão et al., 2010). As for MgO, it is assumed that high stiffness MgO nanoparticles may hinder long-range mobility of polymer chains which increase thermal stability of the polymer (Moaddeb & Koros, 1997). This phenomenon can be verified by analyzing the glass transition temperature (Tg) of the samples. As observed in Fig 4, the Tg of PC5M0 is about 310°C, corresponding to that of the Matrimid Tg. The Tg of PC5M5 is enhanced at 335°C where the stiffness of the polymer is enhanced by applying MgO nanoparticles.
Figure 3. XRD patterns of pristine Matrimid, PC0M5, PC5M0 and PC5M5 membranes, in the range of 5º-80°.
Figure 4. TGA (solid lines) and DSC (dashed lines) thermographs of samples PC5M0 (a) and PC5M5 (b).
3.4 Morphology
The FESEM images of MMMs are shown in Fig. (5), where in sections 5 )a, b and c(, there is no significant accumulation of MgO or PC particles on the membrane surface. This is due to the appropriate of concentration (and, viscosity) and temperature of casting solution rates (Aroon, Ismail, Matsuura, & Montazer-Rahmati, 2010; R. Mahajan, 2000).
As observed in Figs 5 (d, e and f), the cross-sections of MMMs have a crater-type morphology (Ge, Zhou, Rudolph , & Zhu, 2013; Gh & Navarchian, 2016; Shahid & Nijmeijer, 2014b). The creation of elongated matrix around the crater edges is probably because of the interfacial stress concentrations between polymer and fillers (Y. Zhang et al., 2008). Several authors suggest similar morphology for different kinds of nanosized fillers like metal-organic frameworks (MOFs) (Dorosti, Omidkhah, & Abedini, 2014; Ge et al., 2013; Shahid & Nijmeijer, 2014a, 2014b) and ordered mesoporous silica spheres (Khan, Klaysom, Gahlaut, Khan, & Vankelecom, 2013) in various polymer matrices including polyimides. A different morphology is observed, for MMMs containing a micron-size MOF (Ploegmakers, Japip, & Nijmeijer, 2013), Probably indicating that the filler size plays a more important than the chemical/physical nature of components in formation of this morphology.
Here, the presence of particles smaller than 0.1 µ in the center of the craters is probably due to some minor aggregation of MgO particles not present in PC5M0. As to similar particle size in these two membranes, it is assumed that addition of both 5 wt% PC and 5 wt% MgO do not lead to particles' interference, thus, more agglomeration. This is most probably because of difference in the nature of chemical and physical properties of the two fillers. It is assumed that PAni acts as a sizing agent on clay minerals and prohibits their interaction with MgO nanoparticles (Aroon et al., 2010). This can assist the successful incorporation of the fillers at relatively high concentrations in improving the Matrimid gas separation properties.
A few pores are observed in the membranes cross sections. Because these pores are not observed in the FESEM images of the membrane surfaces (Figs (5-a, b and c)), it is assumed that they are not formed along the gas permeation direction and do not make short-cut paths for gas molecules, thus, keeping sufficient gas selectivity for the membrane. The unconnected-pores in the cross section of the membranes are mainly the result of the residual stresses imposed during solvent evaporation and depend on volume of solvent left to be removed when the nascent polymer matrix is vitrified (Moore & Koros, 2005)
Figure 5. FESEM images of PC5M0 (a and d), PC0M5 (b and e) and PC5M5 (c and f). The left and right photos indicate the membranes surface and cross-section, respectively. Magnifications of all images are 20 kX. (The arrows illustrate MgO agglomerates)
3.5 Permeability and Selectivity of Membranes
3.5.1 Matrimid-MgO Membranes
The images of permeability and selectivity of Matrimid-based membranes containing 0-10 % (wt.) MgO are illustrated in Figs 6 (a, b and c). Permeabilities of CO2 and CH4 in pristine Matrimid membrane at 4 bar feed pressure are 7.8 and 0.26 Barrer, respectively, and both increase to about 14 and 0.5 Barrer, respectively, together with increasing MgO concentration to 10%. This phenomenon can probably be attributed to the fact that MgO nanoparticles interaction with Matrimid macromolecules, leading to chain packing within the polymer chains, an increase in their free volume and enhance gas permeabilities (Matteucci, Kusuma, Kelman, & Freeman, 2008). The fact that the CO2/CH4 selectivity is kept high at 28-38 range for various MgO contents and different pressures is expressed in Fig. (6-b). Smaller dynamic molecular diameter and higher condensability of CO2 molecules in comparison with those of CH4 lead to higher diffusion and solubility coefficients of this gas, ending in relatively high CO2/CH4 selectivity values (Chung et al., 2003; Colin A Scholes, Tao, Stevens, & Kentish, 2010). As observed in Fig (6-c), the CO2/CH4 selectivity is enhanced gradually by applying up to 5 % MgO and then a slight fall. This can be explained by two contradicting effects of MgO nanoparticles on CO2/CH4 selectivity. MgO has basic property and may have specific interactions with acidic CO2 leading to an increase in CO2/CH4selectivity at a specified MgO content (Mekhemer, Halawy, Mohamed, & Zaki, 2004). At higher MgO contents, excess free volume and generated voids together with possible agglomeration of particles, deteriorate the CO2/CH4 selectivity (Perez et al., 2014). The sample with 5% MgO (sample PC0M5) is of the best performance among the examined samples, because the CO2 permeability increases up to 35-40% and CO2/CH4 selectivity enhances by 3±0.3 units as compared with that of Matrimid membrane at the test pressures of 4-10 bar, Figs 6(a, b and c).
Figure 6. Effect of MgO content on (a) permeability of CO2, (b) permeability of CH4 and (c) selectivity of CO2/CH4 for Matrimid-based membranes at 4-10 bar and 298 K. Effect of PC content on (d) permeability of CO2, (e) permeability of CH4 and (f) selectivity of CO2/CH4 for Matrimid-MgO (5 wt%) membranes at 4 bar and 298 K. Relative uncertainties are less than 1.6% and 3.2% for permeability and selectivity, respectively.
The permeability of Matrimid-MgO membranes for both gases decreases subject to an increase in pressure from 4 to 10 bar. The permeability of gas through a dense membrane is a product of its solubility and diffusivity coefficients (Baker, 2004):
The gas sorption capacity is defined Eq.(6) (Yampolskii et al., 2006):
where, S is the solubility coefficient and p is the gas pressure. The three-parameter dual-mode sorption isotherm model can describe gas sorption in glassy polymers (Paul, 1979):
where, Kd is the Henry's law parameter, is the Langmuir sorption capacity, and b is the Langmuir affinity parameter. The solubility coefficient is calculated through Eqs. (6 and7):
The solubility decreases subject to pressure, and approaches to the Henry's law parameter at very high pressures. In glassy polymers, the diffusion coefficient for a gaseous penetrant increases slowly at relatively low pressures. This behavior corresponds to the transport model based on dual-mode concepts (Koros, Paul, & Rocha, 1976). The solubility and diffusion coefficient correlation with pressure determines, the permeability pressure behavior. Since the former is dominant, the dual-mode sorption and the mobility models predict a decrease in permeability with an increase in pressure which is mainly due to the lower solubility of gases at higher pressure (Bos, Pünt, Wessling, & Strathmann, 1998; Duthie et al., 2007; Ismail & Lorna, 2002; Wind, Staudt-Bickel, Paul, & Koros, 2002; L. Zhang, Xiao, Chung, & Jiang, 2010).
The effect of MgO content and pressure on the gas permselectivity of membranes, can be analyzed by computing the gas sorption properties of a mixed-matrix membrane based on the additive model as follows (Barrer, Barrie, & Rogers, 1963; Matteucci, Kusuma, Sanders, Swinnea, & Freeman, 2008):
where CMMM, CF and Cpolymer are the gas concentration (the amount of adsorbed gas per volume) in the nanocomposite (MMM), the filler and the polymer (cm3(STP)/cm3), respectively. CV is the gas concentration in the polymer/particle interfacial voids, obtained by the ideal gas law for a given pressure (p) and temperature (T):
Gas concentration in a void is, obtained as being 0.88 cm3(STP)/(cm3 void) at standard conditions. In Equation 9, is the void volume percentage and is the volume percentage of filler, that is:
where, ρF and ρP are the density of filler and polymer, and ωF and ωP are the filler weight and polymer, respectively.
Gas sorption capacity of filler (MgO) is described as a function of pressure by the Freundlich isotherm (Matteucci, Raharjo, Kusuma, Swinnea, & Freeman, 2008):
where, K and n are the fitting parameters as reported by Matteucci (Table 2) (Matteucci, Kusuma, Kelman, et al., 2008). As discussed, MgO indicate a greater sorption capacity for CO2, due to acid-base interaction. Substitution of gas concentration values with each one of the MMM component (from equations 7, 10 and 12) in Equation 9, yields:
The last term (void contribution on gas uptake) in Eq. (13) is neglected when compared with filler and polymer contributions (Matteucci, Kusuma, Kelman, et al., 2008), thus:
Here, the gas sorption capacity of MMMs can be assessed at any pressure and filler concentration. For this purpose, first, diffusion coefficients of both gas types in Matrimid membrane at different pressures are calculated by the time lag experimental method (Equation 3). The gas sorption data of pristine Matrimid are then obtained from permeability data through Eq.s (5 and 6) and finally, the dual-sorption parameters (Kd, C'H, and b) of Matrimid are extracted by fitting Eq. (7) according to Table 2.
In the next step, the effect of MgO nanoparticles on gas sorption properties of MMMs at two different pressures (1 and 4 bar) are calculated through Eq. (14), Table 3, where, the concentration of gaseous penetrants on the MMMs (CMMM) is higher than that of neat Matrimid (Cpolymer), thus the reason for enhanced permselectivity of MMMs when MgO nanoparticles are applied.
Table 2. Freundlich isotherm parameters for gas adsorption onto MgO (Matteucci, Kusuma, Swinnea, & Freeman, 2008) and dual-mode sorption parameters of pristine Matrimid at 25 °C
Table 3. Gas sorption data (cm3 gas in STP/cm3)of MgO, Matrimid and MMMs at two different pressures (1 and 4 bar)
3.5.2 Matrimid-MgO-PC membranes
Permeability and selectivity of Matrimid-MgO-PC membranes (PCxM5) with 5 wt% MgO and different PC loadings are illustrated in Figs 6 (d, e and f) for a typical feed pressure (4 bar). These samples are analyzed in order to assess the incorporation effect of two kinds of fillers on the gas separation properties of Matrimid membranes it is observed that applying PC particles enhances the membrane permeability in both gases types. As observed in Table 1, PC powder is comprised of 80 wt% emeraldine-base PAni. Rebattet and et. al (Rebattet, Escoubes, Pinéri, & Geniès, 1995) have already suggested that the sorption capacities of CO2 and CH4 on emeraldine-base PAni at 1 bar pressure are 4 and 1.5 cm3 in STP/cm3 polymer,respectively. These values are almost in the same order of Matrimid gas sorption capacity reported in Table 3 and also those mentioed in other references (Chung et al., 2003; Moghadam et al., 2011). It is suggested that any possible interaction between penetrating gas types with silicate layers (e.g. Si-OH) do not affect the solubility of CO2 or CH4 on the membranes (Ahn et al., 2008; Anadão et al., 2010; Bhole et al., 2007; Defontaine et al., 2010; Hashemifard et al., 2011; Liang et al., 2012). Thus, the polyaniline/clay (PC) particles do not probably make any significant change in gas sorption properties of fabricated membranes and the enhanced membrane permeability for both gas types at higher PC content is probably mostly attributed to the diffusion term. The SEM analysis of PC indicate a flower-petal like morphology of about 7 nm average pore size (Gh & Navarchian, 2016). The effect of the generated voids at polymer-filler interface is discussed for mixed-matrix membranes by Mahajan. It is found that presence of nonselective permeable regions in the polymer-filler interphase, results in selectivity of MMMs to drop to the selectivity of pristine polymer membrane level (R. Mahajan, 2000). Consequently, due to contradicting effects of tortuosity and void formation on diffusivity of gaseous penetrants, the CO2/CH4selectivity remains almost unchanged upto 5% PC content and then drops when the PC loading is increased to 10 wt% (Fig. (6-f)).A close examination of Fig. (6), indicates that the sample PC5M5 is assumed to have the best performance among the examined samples because its CO2/CH4 selectivity is enhanced by 3.3 units (by MgO nanoparticles), and its permeability for CO2 is increased by 70 % (due to presence of PC) compared to pristine Matrimid membrane. Comparing pristine membrane with three MMMs, each containing totally 10 wt% filler (samples PC5M5, PC0M10 and PC10M0), confirms that the sample PC5M5 has the best permselectivity performance on the Robeson chart (Fig. (7)). This can be verified by FESEM analysis that represents the same distribution of the fillers in sample PC5M5 with samples PC0M5 and PC5M0. This finding declares that incorporation of two kinds of fillers at lower concentrations (5 wt% PC and 5 wt% MgO) resulted in less agglomeration when compared with the membrane with only one type of filler at higher concentration (10 wt% PC or 10 wt% MgO). Here, it can be deduced that the applying PC and MgO with different geometry and physicochemical properties enhance Matrimid permeability and selectivity in CO2 from CH4 separation.
Figure 7. The comparison of permselectivity results of fabricated Matrimid and corresponding MMMs in Robeson chart. All symbols are related to different MgO and/or PC contents. (data for PC10M0 are adopted from our previous work
3.6 Effect of fillers on plasticization resistance of the MMMs
The effect of MgO content on plasticization resistance is analyzed. As pressure increases, Matrimid is plasticized by CO2 at 10 bar pressure at room temperature (Bos et al., 2001; Bos et al., 1998; Bos, Pünt, Wessling, & Strathmann, 1999). As observed in Fig. (8-a), plasticization pressure of the Matrimid-based membrane containing only MgO (without any PC) is increased slightly from 10 bar to 15 bar as the MgO content in the polymer is increases from zero (in pristine Matrimid) to 10 wt%. The reported maximum pplast of Matrimid/nanofiller systems is up to 21 bar in Matrimid/MOF system (Shahid & Nijmeijer, 2014b). Matrimid-PC membranes (without MgO) have plasticization pressure of 30 bar as found in our previous work (Gh & Navarchian, 2016). In other Matrimid-based systems the plasticization has been postponed to 30-40 bar by thermal treatment (Bos et al., 1998), crosslinking (Tin et al., 2003) or polymer blending(Khan, Li, & Vankelecom, 2011) while the permeability and/or selectivity parameters faced significant deterioration.
Plasticization pressure of Matrimid-PC membranes containing 5 wt% MgO (PCxM5)- (Fig. (8-d)) is slightly higher than that of Matrimid-PC membranes (MgO-free) with the same PC content (PCxM0), Table 4. It is suggested that the improvement of plasticization pressure is mainly the result of introducing high modulus rigid silicate layers (Joulazadeh & Navarchian, 2010, 2011) which can entangle with Matrimid matrix and increase the chain stiffness (Ismail & Lorna, 2002), applying high plasticization resistant PAni (Gupta, Hellgardt, & Wakeman, 2006). MgO nanoparticles may hinder intrasegmental mobility of polymer backbone and so suppress plasticization (Ismail & Lorna, 2002).
Because of the plasticization phenomena in the glassy polymers, their gas separation capacity is limited, while one of the important characteristics of a membrane is its operating pressure. The fluxes of treated CO2 in fabricated MMMs (calculated by Equation 4) indicate that by applying 5% PC and 5% MgO in Matrimid, CO2 permeability and pplast improve by 76% and 200%, respectively, while the selectivity is almost unchanged. For this membrane, the membrane capacity (the flux of the treated CO2 through the membrane) can be obtained as 46.8×10-5 cm3(STP)/cm2, Eq. (4), where it is 425% when compared to the flux of CO2 through thepristine membrane in natural gas processing at pplast (30 bar) with the selectivity of 39.7, Table 4.
Table 4. Permeability, selectivity, and flux of CO2 permeate through fabricated MMMs atplasticization pressure (pplast). Data for Matrimid-PC membranes (PCxM0) are adopted from our previous work (Gh & Navarchian, 2016).
3.7 Effect of Pressure on Selectivity of the MMMs
Permeability of CH4 at PC0Mx Fig. (8-b) and PCxM5 samples Fig. (8-e), respectively at 4-30 bar gas pressure are measured to determine the effect of presure on CO2/CH4 selectivity as illustrated in Figs 8 (c and f). It is observed that the selectivity increases with pressure upto 10-12 bar, then remains almost constant at higher pressures. The same behavior is observed in Matrimid-PC samples without any MgO(Gh & Navarchian, 2016). Selectivity is composed of two terms, αD and αS Eq. (2); the former is the most dominant factor in the selectivity of glassy polymers (Yampolskii et al., 2006) and is a function of penetrant concentration in the polymer matrix (Ghosal & Freeman, 1994; Koros et al., 1976). As CO2 is more condensable and diffusive than CH4, its concentration in polymer matrix is higher than that of CH4. At low pressures, concentration of CO2 isjust high enough in the polymer matrix to increase its diffusion coefficient, thus, the selectivity increase with pressure. An increase in pressure increases both, the CH4 concentration in the polymer and its diffusivity, which lead to a constant selectivity at higher pressure.
Figure 8. Effect of pressure on permeability of (a) CO2, (b) CH4 and (c) selectivity of CO2/CH4 for Matrimid membranes with different MgO content at 298 K. Effect of pressure on permeability of (d) CO2, (e) CH4 and (f) selectivity of CO2/CH4 for Matrimid-MgO (5 wt%) membranes with different PC content at 298 K. Relative uncertainties are less than 1.6% and 3.2% for permeability and selectivity, respectively.
4. Conclusions
The focus of this study is on effective application of two types of fillers (MgO nanoparticle and PAni/clay nanocomposite) with different size and geometry into Matrimid-based MMMs. The generated MMMs indicated an enhancement in both permeability and selectivity in comparison with Matrimid for separation of CO2 from natural gas. A crater type morphology is observed for MMMs as a characteristics of Matrimid-based membranes. It is found that PC only enhances gas permeability by the control of diffusivity paths, while MgO nanoparticles enhance both gas solubility and diffusivity. The obtained results indicate that sample PC5M5 containing both fillers at lower concentration (5 wt% PC and 5 wt% MgO) has the best gas separation properties. High pressure tests revealed that sample PC5M5 can enhance pplast and CO2 permeability by 76% and 200%, respectively; resulting in 425% enhancement in the capacity of MMM in the sweetening of natural gas with 39.7 selectivity.
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4x Lipgloss Review! (Revlon, Rimmel, Elizabeth Arden, Sephora)
Back in the days, when I started using make up, I didn't like lipgloss at all. The thought of sticky, way too shiny, gross-looking lips just didn't seem that appealing to me.
However, a while ago I learned that not all lipglosses are like that. Some are actually very pretty…
Today I'm reviewing four lipglosses for you, from drug store to high end. Here they are:
From left to right
- Rimmel London Vinyl Gloss #530 Starlet
- Elizabeth Arden Eight Hour Cream Lip Protectant Gloss
- Sephora Glossy Gloss #03 Precious Pink
- Revlon Colorburst Lipgloss #006 Strawberry
The first lipgloss I want to talk about is the one by Rimmel. To be honest, I was disappointed in both the packaging and the actual product. Although the wand is okay, the rest of the packaging looks a bit cheap to me. I don't like the lipgloss either, it's extremely sticky – which isn't exactly a pleasant feeling on your lips. The colour (a cool pink shade) is quite pretty, but the metallic silver sparkles are not. That's just my opinion, though, I just don't like metallic looking lips.
I already went though two tins of Elizabeth Arden's Eight Hour Cream Lip Protectant, click here to read about why I love that stuff so much. Of course I had to try the lipgloss version of this wonderful balm, which is a clear, scentless gloss without any shimmers. Very basic, but I like it! The gloss definitely makes my lips shinier, but the effect is very subtle – perfect for pairing it with any eye look. Now, let's talk about the texture! It's absolutely divine, very smooth and non-sticky. This gloss is just as moisturising as the lip balm, so you get a shine and a treatment all in one.
This 'Glossy Gloss' (weird name) by Sephora looks a bit like the previous one, it's also a very neutral lipgloss that can be worn with any eye look. But in contrary to the Eight Hour Cream Lip Protectant Gloss, this lipgloss does give your lips a hint of colour. It's a very subtle sparkly peach/pink shade that anyone could get away with, I like it! The texture is a bit sticky, but not as horribly feeling as the gloss by Rimmel. I don't like the watermelon scent, but I got used to that. I'm not blown away by this Sephora Glossy Gloss, but I do like it.
I recently bought this Colorburst Lipgloss by Revlon, because I really wanted to try more of Revlons products. This particular shade, called Strawberry, is a very juicy and fresh pink colour. It contains many tiny glitters that give your lips a pretty sheen to them. I'm impressed by the texture, it feels very nice and soft on my lips. I was silently hoping that this gloss would actually smell like strawberries, but unfortunately it doesn't – it has a nasty chemical scent. But as I said before, I do like the look of this lipgloss and I think it would suit many different people!
Here you can see close ups of my lips, wearing 1) nothing; 2) Rimmel London Vinyl Gloss #530 Starlet; 3) Elizabeth Arden Eight Hour Cream Lip Protectant Gloss; 4) Sephora Glossy Gloss #03 Precious Pink and 5) Revlon Colorburst Lipgloss #006 Strawberry.
Just a little bit about the staying power of these lipglosses. Overall I find that lipglosses don't last on me very long; after one or two hours the colour and shine are both gone. I don't mind that, because it's very quick and easy to reapply a lipgloss – I don't even need a mirror. I din't notice remarkable differences between these four products, although the stickier ones (Rimmel and Sephora) stayed on a bit longer. However, I'd rather have a non-sticky lipgloss that I'd have to reapply more often, because I can't stand that gross sticky feeling.
In short: I hate the one by Rimmel, like the one by Sephora and love the ones by Elizabeth Arden and Revlon. Hope that was helpful!

subset: commoncrawl


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In early December, Confluence Charter Schools was notified that a donor was providing money to help families in need, approximately $1,000 per school. Counselors and social workers were asked to identify students and their families in need. Then, about a week later, the amount of the donation increased, allowing each school to have $2,500 to work with for the families. The donor, however, was kept under wraps until everything was confirmed.
There are five campuses within the Confluence network – Confluence Academy-Old North, Confluence Academy-South City, Aspire Academy, Confluence Preparatory Academy and Grand Center Arts Academy. Confluence educates nearly 3,000 students in pre-kindergarten through 12th grade. Nearly 98 percent of students qualify for free and reduced lunch; some families do not have stable housing and move often; others live in high-crime neighborhoods and there are about 200 students throughout the network who are homeless.
To make sure there would be enough time to shop for gifts, wrap and deliver, Confluence set a deadline of 12:00 p.m. on Friday, December 11 for the schools to submit a list of holiday wishes. No less than five families were identified by each campus; a few families have as many as 9 children. And the children thought not only of themselves, but their siblings who aren't in school and their parents.
Over the weekend, staff shopped for items from the lists – crayons, Barbies, stuffed toys, basketballs, footballs, snow boots, athletic shoes, uniform tops and pants, socks, backpacks, art supplies, board games, coloring books, activity books, journals, Legos, a scooter and an AirStick skateboard, boxes of diapers, children's clothes, nail polish and lip gloss sets, head bands, bath towels and bed sheets, Easy Bake Ovens and cotton candy machines. There are gift cards to stores like Walmart, Target, Burlington and Famous Footwear ranging in value from $20 to $150. The donation also helped buy socks, underwear and toiletries for the schools to keep in their community closets for students.
No longer an anonymous donor, Centaur Building Services – a contract vendor of Confluence – explained their decision to help students.
"Giving back to the community is a personal mission of our family and the Centaur Building Services family of companies," said Janine Dulay, president of Centaur. "We have always been committed to furthering the mission of organizations that help others. A large portion of our proceeds go to mission groups of which we are personally involved that build orphanages in Mexico, dig fresh water wells in India, build schools, hospitals and churches in villages all over the world, as well as supporting organizations right here in our own backyard such as St. Louis Crisis Nursery and many others in the area.
"At a recent meeting at Confluence, it was disclosed that there are about 200 children in their schools who are homeless. Frank Joubert, our CEO, and I were deeply touched by this revelation and we discussed the opportunity to help with Confluence."
"Being raised in a very poor home and being a product of the inner city public school system, our family knows all too well the challenges and desperation these families feel when it comes to providing even the basic necessities for their children. It was an automatic reaction. We knew we had to help," she continued. Dulay and Joubert are brother and sister.
"If we show support, understanding and compassion for those in need, it is our hope that we inspire them to continue that behavior throughout life, where they become productive, contributing members of society who find the joy in paying it forward," said Dulay.
"We are grateful and thankful for Centaur's generosity," said leaders of Confluence Charter Schools. "It shows their dedication to our students and the community. We may never know the full impact of their gift, but we do know it will make this holiday special for some of our students and families."


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Former Bachelorette star Jillian Harris has reportedly praised Bachelor contestant Vienna Girardi, describing her as a "sweetheart".
Girardi, 23, became engaged to airline pilot Jake Pavelka during this month's season finale of the ABC romance reality show after he chose her over fellow finalist Tenley Molzahn.
Speaking to TV Guide, Harris said: "At first, I really didn't think she was a good fit.
"I always thought Tenley was a better fit and I was worried for him if he was going to pick her, but I did toward the end see a different spark with him. He became a little bit more laid back, a little bit goofier, a little bit more comfortable in his own skin with her, which he really needed."
Harris, who became engaged to Ed Swiderski during her own stint on The Bachelorette, continued to say that she recently met Girardi and thought she was a "real sweetheart" who has a "big heart".
"She may have done some stupid things when she was young. We all have, but those are things that happened when she was just fresh out of high school," she said. "She's changed and she may not be as mature as we all want her to be or as old as we want her to be, but she's actually a sweetheart and she does have a big heart."
> 'Bachelor' Jake, Vienna visit Disney World


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Btw, Happy Birthday Juri! <3 Wishing you all the best! You're a blessing to the world and I hope you get all the pampering you deserve!
Attention pooled at the center of the dining hall at the clang of a metal tray hitting the floor. Someone's food landed in a wet splat as cutleries bounced off the concrete, chiming in to echo sharply across the walls.
The pretty blond newbie frowned at the guy who walked into him. Eyebrows slanted sharply upwards above eyes overcast by shadows, his glare was darkly beautiful but sharp enough to kill.
"Oopsie, sorry!" Fukka laughed, lifting both palms to the air. His sarcastic tone made it known that it was no accident, and Taiga was not impressed the slightest. "Didn't think you'd be such a pushover with that face," he mocked, bending forward to smirk in Taiga's face.
Taiga rolled his eyes, looking away with a bored expression. "Well if the food is what gave you that breath, I'd rather skip it," he said, lifting a hand to cover his nose.
"What the fuck did you just say?!" Fukka yelled, grabbing Taiga by the collar, pushing the slender boy back a few steps.
Taiga's glare did nothing to calm Fukka's anger. "Don't think I'll go easy on you just cause you're pretty!" Fukka threatened, but Taiga wouldn't falter.
"What're you gonna do? Run to your big beefy friends for help?" Taiga taunted, a dangerous glint in his eyes.
With a yell of pure rage, Fukka yanked Taiga by his tiny ponytail, earning a pained yelp as he caught Taiga off guard. Spinning Taiga so his back was now pressed against Fukka's chest. "Not so tough now, huh?" Fukka taunted, face only inches away from Taiga's porcelain skin.
Taiga grimaced in pain, but he fought back nonetheless, hands wrapping around Fukka's wrist. Straining against Fukka's grip, he pulled the hair tie off his hair, loosening Fukka's grip on his scalp. Pulling down on Fukka's arm with all his might, he flipped him over his shoulder and onto the floor.
Juri watched as Fukka held fast, pulling Taiga down with him, landing on the floor with a loud 'oof'. Rolling so that he ended up on top of Taiga, straddling him, he wrestled Taiga's arms to the ground. But try as he might, he couldn't free his arms for long enough to land any punches, Taiga proving to be more of a fighter than he first seemed.
Juri couldn't stand around watching anymore, getting up swiftly to approach the two. He pushed through the gathering crowd of boys egging on their fight. Obviously eager to see the fresh blood on the floor.
"Fukka!" Juri yelled, pulling the dark haired boy back. "Stop it! The guards are coming. You've already been warned haven't you?"
"What? Trying to be a knight in shining armor, Juri? Don't give me that bullshit."
With the time that Juri had stalled, they could already hear shouting along the corridor as more guards approached the dining hall.
Fukka clicked his tongue, throwing glares at both Juri and Taiga as he left. "Don't think it ends here, dimwits."
Taiga left, barely uttering a word of thanks. Stealing a bread roll off a random tray as he left the room.
The next time he meets Taiga is in the corner of the courtyard. Hidden in the shadows, Iwamoto, Date and Fukka had him pinned against the wall. Date's long fingers clamped around his mouth so he wouldn't make a sound.
"HEY!" Juri yelled at them, hands slipping into his pocket for his trusty flip knife as he stormed up to the group.
Fukka took one look at him and groaned. "You again?"
"Stay out of this, Tanaka," Iwamoto warned him. "You can still walk away now. Pretend you didn't see anything."
Juri snorted. "Nah, I'm not as low as you." Pulling out his knife he took a swipe at Fukka first, making him stumble backwards into the wall. He pointed it at Iwamoto next, stepping into his personal space so he'd back away from Taiga.
Iwamoto looked down on him, eyes on the blade in front of him. "Where the fuck did you get that?"
"That's a secret," Juri said with a wink.
Suddenly hands wrapped around him from behind, Fukka grappling him when he was distracted by Iwamoto. Jumping onto Juri's back to choke his neck with his arms. Juri swerved, ramming Fukka against the wall, smacking him with an elbow to his side.
He heard a scream, looking to the side, Date was cradling an injured hand where Taiga bit him, the slender one shoving him away easily with everyone's attention on Juri.
As a warning, Juri swiped at Iwamoto's chest, barely scraping his skin, but a gaping gash tore through the fabric. "The next swipe will draw blood," he threatened, knife rising to Iwamoto's face. "Or take away an eye maybe?"
"You're no fun," Iwamoto said clicking his tongue. "Let's go," he told the others, cocking his head to the door. "It's not like you've anywhere to run," he added just before leaving.
Juri sighed, shoulders relaxing as they retreated, turning to face Taiga. "You okay?"
Taiga's eyes met his. "No one asked you to save me."
"Well, I was the pretty fresh meat once," Juri said. "Though I probably don't look it now," he added laughing.
He watched as a smile made its way to the blond's features. "Did they jump you too?" Taiga probed, a teasing smile lingering on his lips.
Juri did a double take, not expecting such a crude question to come from someone so pretty. "What?"
"It's nothing to be ashamed of," Taiga shrugged. "I was jailed for prostitution after all." Taiga fluttered his eyelashes in mock innocence as Juri coughed, looking away. "I just didn't like being forced into it, but I was prepared to take it if necessary."
"Heeeh," Juri nodded in acceptance, not really knowing what to say. Who was he to judge anyone's past when he was in here anyway?
With a mischievous look, Taiga strolled up to him, a pale hand going straight for his crotch. He grinned. "I knew it, you're pretty big for your frame," he commented, making Juri blush bright red.
"What?" Juri looked at him, eyes wide. This was not what he expected but damn Taiga was pretty up close.
"Hmm, I thought you saved me because you wanted to be rewarded," Taiga teased, hands running up his body to wrap around his neck.
Leaning in to kiss him softly, Taiga trailed his fingers back down Juri's torso to land on his belt. Juri was mesmerized, watching those long lashes bat softly at him as they pulled apart. Suddenly a marionette to Taiga's whims.
Taiga pushed him against the wall, kissing him hungrily, tongue darting against Juri's. He faintly heard the clink of his belt as Taiga worked them open without sparing a glance downwards, obviously familiar with the routine. Either he was telling the truth about the prostitution or he was just promiscuous by nature.
His thoughts didn't stray much further than that, his full attention back on Taiga now that his fingers had wrapped around him. There was just something about the way they moved that sent tingles of excitement across his skin. He broke their kiss to gasp sharply when he felt Taiga's thumb run over his sensitive head.
The lopsided smile Taiga shot him was dangerous, wild, and sweet all at once, his cock mirroring his anticipation for what's to come. He exhaled, shoulders relaxing against the brick wall as he watched Taiga go down on him.
A pink tongue darted out to lick teasingly at his hardening cock, long fingers spreading his saliva around to glide more smoothly across his skin. He pressed a palm to Taiga's cheek, thumb caressing his cheekbone. The blond hummed, kissing his palm before kissing his cock instead. Taiga looked up through his lashes, lapping up his length slowly, tongue circling his tip in equal slowness.
Juri groaned. When Taiga opened his mouth wide, his cheeks hollowed out making his cheekbones even more prominent. "Fuck," Juri hissed when those pink lips finally wrapped around his cock. It was just perfect. Soft lips dragged across his skin, the friction just so perfect, he choked back a moan, hands running through those long blond locks.
Just when he thought it couldn't get any better, Taiga took him deep, swallowing around him, humming like he loved it just as much as Juri did. He bobbed his head and Juri almost blanked out, but he couldn't bear to miss a second of the sight before him, so he grounded himself with the soft hair running through his fingers. Tugging at them softly, muttering a stream of curses.
Juri didn't last very long, come shooting into Taiga's mouth. And Taiga pulled back, letting Juri catch a glimpse of the milky liquid on his tongue before he swallowed it down. Licking his lips after.
Panting as he recovered from his high, he watched as Taiga stood up, smiling at him like an angel.
"That will be 100,000 yen. I'll put it on your tab, so thanks for your patronage," Taiga grinned cheekily, shooting him a wink as he walked off.
It's your turn, kira_shadow! Good luck!


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Collection Villeret 1858 Vintage Tachydate Red Gold by Montblanc
The "Collection Villeret 1858 Vintage Tachydate Red Gold" is a member of Montblanc's "Collection Villeret 1858" collection. The Watch features a dial in solid gold with ivory lacquer finish and a red gold case. This timepiece was designed for men. The round case has a diameter of 43.5mm, a height of 13mm and is water tight up to 3 bar (approximately 30 m water depth). A transparent case back offers a view of the movement.
The watch is based on a hand-wound Montblanc MB M16.32 mechanical movement which has a power reserve of 50 hours and displays for hours, minutes and seconds (off-centered). It offers the popular chronograph "stopwatch" function to measure the duration of an event. The measured duration can be read with an indicator for the seconds. The movement indicates the date. Other features of the watch: tachymeter scale.
The timepiece comes on a brown alligator leather strap with a red gold pin buckle. Production of the watch is limited to 58 pieces. Montblanc asks its official retailers to sell the watch at around 58'000 CHF. You can use the "Contact Shop" button to ask an official store of your choice for their offer."


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Writing Press Releases to Market Your Small Business
Throughout my career as a technology marketing professional, I have spent a lot of time counseling small businesses on effective marketing, and helping them to justify investments in marketing. Often times, they have tried a tactic or two, without understanding what their overall strategy should be, or how different types of campaigns are designed to bring different types of results.
As a small business owner or marketer, it is key to invest in marketing to promote your product or service. This does not have to be an overwhelming or costly endeavor, and there are many smart marketing plays that are proven for small business. You can start by downloading our free "Smart Marketing Playbook" article, Using Press Releases to Promote Your Small Business.
Writing press releases to promote each of your business successes is a easy, actionable strategy that can fits any marketing budget. What results can you expect you ask? Issuing press releases regularly helps to keep your company top of mind with prospective customers; it builds awareness for what you do, and the value you provide; and it is a "smart marketing play" that can get your company known.
The press release has also evolved, from a simple news announcement sent only to journalists and media outlets, into a powerful marketing tool for organizations of all sizes. With the Internet and social media venues as prominent communication vehicles for both business and consumer audiences, readers can come across your news in several places, and can take multiple actions after viewing your announcement. For example:
- Press releases can be indexed by Yahoo and Google, and shown in search engine results.
- Press releases can be posted to your company website and optimized with your keyword phrases to improve your search rankings.
- Press releases can be re-tweeted by readers to their followers on Twitter, who share the same interests.
- Press releases can be used by your sales teams as conversation starters on cold calls.
- Press releases can be pushed out to mobile phones, through RSS feeds, and redistributed to news syndication and aggregator sites.
- Check out our marketing templates downloads page
- Access our Press Release Tutor interactive templates, and
- Subscribe to the Smart Marketing Basics blog for continual marketing tips and help.
Trackbacks & Pingbacks
- Three Press Releases to Grow Your Small Business « Smart Marketing Basics pingbacked on 8 years, 11 months ago
- Press Release Distribution Strategies for Small Business « Smart Marketing Basics pingbacked on 8 years, 11 months ago
- How Technology VARS and Resellers can benefit from PR « Smart Marketing Basics pingbacked on 8 years, 9 months ago
- Crafting the Perfect Company Boilerplate Description for Your Press Releases « Smart Marketing Basics pingbacked on 8 years, 5 months ago
- Growing Your Small Business with Public Relations « Smart Marketing Basics pingbacked on 8 years, 2 months ago
- How to Distribute Press Releases « Smart Marketing Basics pingbacked on 8 years, 2 months ago


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6130 Bellastead Drive, Charlotte NC 28214
at Bellastead
Call 888-207-0371 to connect with the builder right now!
Save this Home
to the NHS Mobile App
Tour This Home
6130 Bellastead Drive, Charlotte, NC 28214
Hours Mon, 1-6; Tue-Sat, 10-6; Sun, 1-6;
Same-day scheduling unavailable online. To request a same-day tour, please call the builder #phoneNumber
Please be aware that current conditions may impact hours of operation.
Valued Partners
Want to see more details?
Book a virtual tour with a builder expert.
Own an affordable ranch home with maintenance-free lawn care off Moores Chapel Rd! Arrive in the Dominica floorplan to bedrooms on both sides. If you'd like an office or study space, choose to make one of them a flex room. Past the bedrooms is a dining room down the hall from the kitchen. The kitchen and great room have an open concept so you never miss a moment with guests! Tucked away is the Owner's bedroom that features an ensuite bath and walk-in closet. At Bellastead you'll have an affordable home and a convenient location. You'll be within a mile of I-485 and I-85. Running errands will be easy with Walmart and Harris Teeter close. Stop by the model today to learn more! *Prices shown generally refer to the base house and do not include any optional features. Photos and/or drawings of homes may show upgraded landscaping, elevations and optional features and may not represent the lowest-priced homes in the community.Visit the Builder's Website
6130 Bellastead Drive
Charlotte, NC 28214
Visit and take the app with you!
Click to get the NHS Mobile App
If you're looking for modern designfeatures in your home and a low-maintenance lifestyle,schedule a visit toBellastead! Bellasteadoffers affordable ranch homes with maintenance-free lawn care allinan ideal location. When you choose your home at Bellastead you'll have options for 2-3 bedrooms, 2 bathrooms,1,100-1,700sq. ft. and a 2-car garage. Some floorplans even have a flex room for that home office or extra hangout space. Plus, your new home will have conveniences you won't get in an older home such as a 10-year structural warranty and energy-saving appliances, giving you peace of mind and saving you money on monthly bills. Ready to learn more? Schedule a visit to Bellastead!
Area Schools
Actual schools may vary. Contact the builder for more information.
Home is where the heart is—yours and ours. Our passion—and our purpose—is making places people love to call home. What began in 1948 as a small, family-run business in Pittsburgh has evolved into one of the top five home builders in the nation. Today, Ryan Homes builds new homes in twenty-seven metropolitan areas in fourteen states and the District of Columbia. We're a proud member of the NVR family, a distinguished group that also includes NVHomes, Fox Ridge Homes, and NVR Mortgage. What is the secret of our success? There are several: unparalleled customer service, innovative designs, quality construction, affordable prices, and desirable communities in prime locations. Not to mention our industry-leading comprehensive warranty coverage and customer care after move-in. It's no coincidence that customer referrals are responsible for a large percentage of our home sales. First-time buyer, move-up buyer, empty nester—buyers of all ages and stages of life can find exactly what they are looking for in a Ryan home.


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This set of 24 mini cards is perfect for handmade gifts or orders. A hand-drawn sewing machine with room for a sweet note. Choose between aqua or pink.
These are cards printed with my hand drawn, original, ink illustration. I have digitally edited and added text creating a happy collection of stationery for you. Each card measures 2.75 by 4.25 inches and is printed on white linen paper.
I carefully package all my in a protective, cello envelope and shipped in a rigid mailer.


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North East chartered surveying firm Bradley Hall is forging a close relationship with Lloyds Bank in the North East after being appointed on the prestigious Lloyds Bank Valuation Panel for Secured Lending.
Lloyds Bank operates a network of 1,300 branches across England and Wales, offering a full range of financial services. The company, which was renamed from Lloyds TSB in 2013 employs almost 46,000 people across its branches and headquarters.
"Our knowledge of the local market will help Lloyds Bank to further strengthen their offering to customers in Newcastle and the North East, as well as expand our business opportunities."Richard Rafique, director at Bradley Hall, said: "Lloyds Bank is traditionally thought of as one of the 'Big Four' clearing banks and enjoys a solid reputation for customer satisfaction and we are delighted to announce our participation on the valuation panel for secured lending.
Its Grey Street office in Newcastle city centre focuses predominantly on commercial property, with plans to open a residential operation within the building in the coming months, while the Gosforth office deals mainly with residential enquiries. The Durham office, led by director Peter Bartley, performs a dual role in managing commercial and residential instructions, with a fifth residential office based in Morpeth set to open this spring following a successful office launch in Alnwick last year.In addition to its partnership with Lloyds Bank, Bradley Hall has worked on the regional panel of Barclays Bank for over 20 years and has previously undertaken work via the prestigious HSBC panel and Handelsbanken. The firm offers a broad range of services from residential and commercial estate agency through to property management, investment, business sales and disposals.
The company also recently announced an expansion and diversification, offering a comprehensive range of independent finance advice with the launch of BH Financial Services. This service, approved and regulated by the Financial Conduct Authority (FCA), will provide advice on residential and commercial mortgages, commercial loans, to business finance, and motor finance for business and private use along both vehicle sourcing and disposal .


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The twentieth episode of VARVET INTERNATIONAL contains: American actor Mark Boone Junior on music, his biggest problem with Sons of Anarchy, acting, violence, Christopher Nolan, Spun, Steve Buscemi, protectmustangs.org, alcohol and drugs, money, Swedish seafood, and the American election. VARVET INTERNATIONAL is sponsored by uber. Host: Kristoffer Triumf. Producer: Christina Jeurling Birro. Editor: Lovisa Ohlson. Theme song producer: Maria Marcus. Music: Mark Boone Junior - Bang Bang (cover) Extra cred to: Timmie Strandberg/podbyrån who helped us with EQ.
An idiot abroad? Well, it's a Swede abroad! From time to time, I take on a guest and talk about drive, background, politics, dreams, work (VÄRVET is Swedish for "the task"), and the future. All in all, the Swedish and the English spoken versions of VARVET have been downloaded some 70,000,000 times. I hope you'll contribute with another one. Best, Kristoffer Triumf, Stockholm, Sweden


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Wednesday, January 30
Bright as a Button
Before Christmas we had a review with SALT (speech and language therapist) who ended it with "I'm not really concerned but....*trots out not one but two further referrals concerning lack of speech*". I was left thinking, jesus woman, just SAY IT-it's alright, I had actually noticed that most two and bit years olds have more than about 10 words on a really good day and thus things weren't running as smoothly as they could! It really frustrates me when people try and sugar coat things before ramming another thing through that just highlights you're in a pickle. I know they do it not to scare you silly and set off the presence of the almighty (and frequently wrong) Dr Google, but then what actually happens is that you just get a bigger unpleasant shock when surprise, surprise, the next blunt-er professional you see says, "Do you know your child is delayed ...*insert delay shocker here* months?".
So anyway, we were referred to one speech parent & child group and also to the Early Years Support team, who are similar to portage. We are still waiting to the former as there is a waiting list and we had the latter meeting yesterday. It went better than I had hoped. Essentially, it was a play assessment to judge Wriggles' maturity through play and catch a glimpse of what amounts to her learning abilities and to get an idea of her intellectual capacity. Although speech does come into it, it helps to know if you're looking at a child with delay in all areas e.g. immature speech and some cognitive delay or immature speech on it's own. I was fairly confident that Wriggles is more or less on track cognitively and definitely for corrected age; then again I think the sun shines out of her arse so am probably not the best objective judge.
The meeting was off to a good start when H, the EYS (Early Years Support) worker said Wriggles' reputation had preceded her and she has heard for months from her colleagues who know Wriggles through physio and Splish, Splash, Bounce that Wriggles is simply a sunny delight encased in a mad toddler. Cue first proud mum moment. Together with our SALT, we sat and watched and interacted with Wriggles playing around the room as well as vaguely discussing her history, what else is going on health-wise for her, future plans for nurseries and her communication boundaries. Pretty quickly, H said she felt that there was very little they could do from a referral point of view right now. Wriggles was clearly "as bright as a button" (second proud mum moment) and was demonstrating a good overview of play, both independent and social and seemed to have a good grasp of concepts, problem solving and memory. She did discuss with our SALT, C, about possibly referring us to a group of children with language delay just on single words (definitely us. I will fall over with surprise when Wriggles strings words together) but after the pair of them talked about it, it was decided that although that fits Wriggles' language needs, unlike the rest of the children currently in the group she doesn't have the cognitive delay also, so H felt the group would not push her enough as she needs appropriate input to facilitate speech.
What this all essentially means, and the main thing that came out the meeting, is that when we come to looking at playgroups, nurseries and school we are looking at going into mainstream establishments. We will stay on EYS books so that when the time comes they can help us pick the most appropriate places and broker any meetings, alongside physio and the community nursing team. Depending on progress, it will need to be liaised to ensure it is a setting compliant with Wriggles' physical needs (which physio would mange, maybe by providing a walker or other mobility aid and possibly some assistance at times) and also a place supportive of Makaton and BSL signing as this still plays a big part in our lives and routine. I had worried that the physical and language delay might hold her back, and in one way it does. I have noticed, in her correct peer group, Wriggles does get left out physically because she hasn't the ability to run off, jump, move around in great strides-she is reliant on someone or something to move her. In a slightly younger group, it is still an issue but less so as slightly younger children don't bat an eyelid about crawling around or having a mum-walker whereas already I have seen 2- and almost 3 year olds 'baby' Wriggles in group situations because she seems at first glance, slightly more babyish in her movements or exchange of communication. But in another way, this meeting affirmed what I hoped to be true, that despite having some extra hurdles to overcome, Wriggles, possibly with some extra support and the right setting, should be able to settle nicely in her peer group and not just cope but thrive. H noted that through play, even though she doesn't have the speech currently, Wriggles demonstrated enough understanding and interest to be more than able to "join in" even in a less vocal capacity. Of course this is very early days, we haven't tried an educational setting yet and there is the whole other issue of needing feeding and a few sensory quirks Wriggles has. But one step at a time.
Because right now, I'm doing a jig on the moon and no-one can spoil it!*
This is possibly the first time we have had a meeting and not come out with another referral or after having another issue flagged up.
This is a great step when professionals note down Wriggles positives as well as problems.
This is one of the first times, if not the first time, I have come out thinking maybe, I am doing something right after all. Maybe I haven't buggered things up for her by either prematurity (thanks a bunch, womb), my own struggles with my mental health or by not being super mum with a play date here, an award winning toddler group there, French lessons, baby yoga, yadda yadda yadda.
This is a moment I will savour and remember next time some ignoramus says "So, isn't she walking or talking yet? Why?".
We might not have left behind prematurity or medical needs, but it is so nice to celebrate something for a change with those who oversee her development. And by the way, "nice" doesn't even do it justice. It is EPIC.
*don't you dare. Let me have my minute!
4 comments:
I'm glad you had your "proud mum" moments. When I was a young mum (years ago) I found it so hard when everyone commented on how shy my third daughter was, compared with her more extrovert older sisters. Then finally in the Lower Sixth(!!) a wonderful teacher got the message, saying: "Perhaps she's just fine as she is and we shouldn't try to change her!" Too right! (She's grown up into a wonderful young woman, wife and mother...)ReplyDelete
So pleased you had a proud mother moment. Its great isn't it. But I'm not surprised. All your photos and your stories about WRiggles show a very bright little girl, blessed with a wonderful mummy, and Wriggles has the determination to overcome any challenges on the way. You can see that in her face too. Enjoy your proud mummy moment: there will be lots more.ReplyDelete
You have your moment lady! You fully deserve it! It's times like this that show how excellent parenting makes a difference, aim for the sky and higher! XReplyDelete
What Leanna said! Wriggles is such an amazing little girl :) xReplyDelete


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People are flocking to Bend, Oregon and why wouldn't they? Bend offers outdoor recreation year round; a vibrant, friendly community; breathtaking views of the Cascade Mountain range; world-renowned golf courses and nearly 300 days of sunshine per year! Add to that great schools, latest medical facilities and family friendly parks and restaurants. It's no wonder many families want to make Bend Oregon home.
The challenge is finding a home. As quick as they come on the market, they're sold or pending. Buyers are offering above asking price just to secure their offer. Fortunately there is a new community to break ground in Bend Oregon. Franklin Brothers home builders is answering the demand for Single Family Communities. They will be breaking ground on a 90-acre neighborhood named Stone Creek in southeast Bend. This community will have single family homes, apartments, townhouses, an elementary school and a city park.
Cascade Business News met with Darrin Kelleher of Franklin Brothers and he tells them why their communities set Franklin Brothers apart from other Bend home builders.
All we know is we're happy to have more beautiful homes, apartments and townhouses for families of all sizes to come live and be able to enjoy all Bend Oregon has to offer.
What is one of your favorite communities in Bend? Leave your comment in the section below.


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'This boy has bought me. This white boy who don't even look as old as I am. He owns me body and soul and my worth has been set at six hundred dollars.'
Samuel's an educated boy. Been taught by a priest. He was never supposed to be a slave.
He's a good boy too, thoughtful and kind. The type of boy who'd take the blame for something he didn't do if it meant he saved his brother. So now they don't call him Samuel. Not anymore. And the sound of guns is getting ever closer…
An extraordinary tale of endurance and hope, Jon Walter's second novel is a beautiful and moving story about the power of belief and the strength of the human spirit, set against the terrifying backdrop of the American Civil War.
How did I get the book? StorytellersInc Book Club
Genre: Historical Fiction
Review: Samuel is a very engaging narrator, so getting lost in his story was easy. What wasn't easy is the story itself. Emotionally I felt drained, horrified and experienced a rollercoaster of emotions the deeper I got into the book. This is good. Very good, because Samuel's story should have you feel.
Admittedly this period in history isn't something I'm overly familiar with. I knew the basics but that's about it. I felt that reading My Name's Not Friday taught me more about American Civil War, the human cost and why people would do the things they did. What Jon Walter's book does is make everything alive. It's not just Samuel but the other characters as well, you're drawn into their lives and experience the unfairness (that word doesn't even begin to cover it).
I wanted to rescue Samuel. I wanted to scream and shout at the despicable people he encounters. I wanted to shake some sense into those that just wouldn't listen. Most of all I wanted this to be fiction not historical fiction, because it made me feel so much. Samuel might not have been real but that period in history exists and it's harrowing.
Recommend it?


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China To Expand List Of Countries To Pay Tariffs On Sugar Imports
Published on Jul 16 2018 9:59 AM in Supply Chain tagged: China / Sugar / Tariffs / ICE
China's Commerce Ministry said on Monday it will expand the list of countries which must pay extra tariffs on sugar imports, starting from Aug. 1.
This comes just over a year after introducing hefty penalties on top growers including Brazil and Thailand.
In May last year, the government hit major exporting nations with penalties on sugar imports after years of lobbying from domestic mills, but exempted 190 smaller producing countries and regions, mostly in Southeast Asia and South America, like El Salvador and the Philippines.
Speculative Selling
Elsewhere, raw sugar futures on ICE fell to a two and a half month low last Thursday, pressured by an early spurt of speculative selling that pushed prices down 1.7 percent within the first seven minutes amid lingering worries about abundant supplies.
Speculative selling in the first seven minutes of the session pushed prices below technical support levels around 11.12 cents, which triggered automatic sell orders and attracted fresh selling, dealers said.
Focus also remained on ample global supplies, although participants were monitoring dry weather in Brazil that could curb output further.
Earlier this month, Associated British Foods said that low sugar prices led to a 17% decline in revenue at its AB Sugar division, with the forecast for the full year likely to be muted.
News by Reuters, edited by ESM. Click subscribe to sign up to ESM: European Supermarket Magazine.


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