Biobutanol
Butanol may be used as a fuel in an internal combustion engine. Because its longer hydrocarbon chain causes it to be fairly non-polar, it is more similar to gasoline than it is to ethanol. Butanol has been demonstrated to work in vehicles designed for use with gasoline without modification. It has a four link hydrocarbon chain. It can be produced from biomass (as "biobutanol") as well as fossil fuels (as "petrobutanol"), but biobutanol and petrobutanol have the same chemical properties.
Butanol from biomass is called biobutanol. It can be used in unmodified gasoline engines.
Biobutanol can be produced by fermentation of biomass by the A.B.E. process. The process uses the bacterium Clostridium acetobutylicum, also known as the Weizmann organism, or Clostridium beijerinckii. It was Chaim Weizmann who first used C. acetobutylicum for the production of acetone from starch (with the main use of acetone being the making of Cordite) in 1916. The butanol was a by-product of this fermentation (twice as much butanol was produced). The process also creates a recoverable amount of H2 and a number of other by-products: acetic, lactic and propionic acids, isopropanol and ethanol.
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