Global Processing

Lab finds new method to turn biomass into gasoline

April 27, 2009
U.S. scientists have combined a discovery from a French garbage dump with breakthroughs in synthetic biology to come up with a novel method for turning plant waste into gasoline, without the need of any food sources, according to Reuters. A synthetic biology lab at the University of California San Francisco identified a compound able to use biomass to produce a gas that can be converted into a gasoline chemically indistinguishable from fossil fuel based petroleum. Their method allows for a variety of feedstock to be used that are nonfood sources, such as agricultural waste products like corn stover and sugar cane bagasse. Critics charge that making ethanol from corn helps drive up food prices and is not an environmentally sound way to produce a so-called green fuel. The scientists said gasoline they were able to produce carried the same chemical and molecular makeup as gasoline from oil refineries. Scientists said that the United States could look to biological sources for a large percentage of its gasoline when oil prices are high. Scientists previously tried to find an enzyme that could break down the cell walls of plants to help make biofuels but failed. The lab used a bacterium discovered in the early 1980s living in a French garbage dump. They combined the bacterium with yeast, which can make different chemicals. When mixing this compound with biomass like switchgrass, the bacteria consume the grass and produce the chemical acetate. The yeast eats the acetate and converts it into methyl halides, molecules traditionally used as agricultural fumigants. The methyl halides come off as a gas that can be collected and converted into gasoline. By using different catalysts the methyl halides can also be converted into other useful chemicals, such as the ethylene used to make plastic bags. Marine algae, fungi and other organisms, according to the UCSF lab’s paper in the Journal of the American Chemical Society, naturally produce methyl halides. But it''s produced in such low yields that it was not of use to industry. These results demonstrate the potential for industrial production of methyl halides from nonfood sources to make gasoline. The first large-scale pilot plant could be built in three years. The lab''s discovery was helped by breakthroughs in synthetic biology over the past few years. Labs can now design a piece of DNA on a computer, email it to a DNA synthesis company and have the actual DNA mailed to them in a matter of weeks.