U.S. researchers develop new way to boost biofuel production

WASHINGTON, Aug. 19 (Xinhua) -- Researchers at Ohio State University have developed a new way to double the production of biofuel butanol, which might someday replace gasoline in automobiles, the university said on Wednesday.

The process improves on the conventional method for brewing butanol in a bacterial fermentation tank, the university said in a press release.

Normally, bacteria could only produce around 15 grams of the chemical for every liter of water in the tank before it would become too toxic for the bacteria to survive, said Shang-Tian Yang, professor of chemical and bio molecular engineering at Ohio State.

Yang and his colleagues developed a mutant strain of the bacterium Clostridium beijerinckii in a bioreactor containing bundles of polyester fibers. In that environment, the mutant bacteria produced up to 30 grams of butanol per liter.

Right now, butanol is mainly used as a solvent, or in industrial processes that make other chemicals. But experts believe that this form of alcohol holds potential as a bio fuel.

Once developed as a fuel, butanol could potentially be used in conventional automobiles in place of gasoline, while producing more energy than another alternative fuel, ethanol.

Yang said that this use of his patented fibrous-bed bioreactor would ultimately save money.

"Today, the recovery and purification of butanol account for about 40 percent of the total production cost," Yang said. "As we are able to create butanol at higher concentrations, we believe we can lower those costs and make biofuel production more economical."

Currently, butanol costs approximately three dollars per gallon-- a little more than the price of gasoline.

The researchers are applying for a patent on the mutant bacterium and the butanol production methodology, and will work with industry to develop the technology.