The dominant ethanol feedstock in warmer regions is sugarcane. Maize is increasingly used as a feedstock for the production of ethanol fuel. It may also have use as a bioethanol or bioenergy feedstock. There is some debate in the classification of certain biomass feedstock as wastes. Maize is widely used in Germany as a feedstock for biogas plants. When ethane is the feedstock, ethylene is the product. Bio-ethanol is usually obtained from the conversion of carbon-based feedstock. Experimentally, ethane is under investigation as a feedstock for other commodity chemicals. Furfural is an important renewable, non-petroleum based, chemical feedstock. It is also used as a petrochemical feedstock. Toluene is predominantly used as an industrial feedstock and a solvent. Isobutane is the principal feedstock in alkylation units of refineries. He recognized the importance of petroleum as a feedstock for petrochemicals. Since then, ethylene is the dominant feedstock. Economics for solid feedstock indirect FT process plants are further confused by carbon regulation.