In the search for renewable energy sources, researchers have used everything from banana peels to algae to create new biofuels. Throwing a new idea in the mix, researchers at the U.S. Department of Energy’s Joint BioEnergy Institute (JBEI) discovered a promising source for biofuel from methyl ketones, originally found in the fragrant evergreen plant, rue. While we don’t think this means your gasoline will smell like Christmas trees, it could make your commute a bit sweeter.
To evaluate a successful fuel, researchers measure the cetane rates of a substance and give it a subsequent diesel fuel rating—similar to the octane number you see at the gasoline pump. The higher the cetane number, the shorter the ignition delay period. In the United States, diesel fuel must have a cetane rating of at least 40. Methyl ketones scored an impressive 58.4 in testing led by JBEI microbiologist Harry Beller, making it a promising candidate for biofuel.
Methyl ketones have been found in tomatoes and other plants as well as insects and microorganisms and are used to provide the scent in essential oils and to flavor cheese and dairy products. While ketones do occur naturally, Beller’s team is working on producing them in larger quantities using engineered E. coli bacteria to break down glucose. “Our findings add to the list of naturally occurring chemical compounds that could serve as biofuels, which means more flexibility and options for the biofuels industry,” says Beller
While the compounds show a lot of promise, we’re still a long way from seeing methyl ketones powering your engine. Beller and his team will next work on increasing production and perfecting the fuel properties of the methyl ketones in hopes that their discovery will provide a new, renewable option at the pump.