Cheaper butanol production method

Engineers at Ohio State University have found a way to double the production of the biofuel butanol, which might someday replace petrol in cars.

The process improves on the conventional method for brewing butanol in a bacterial fermentation tank.

Normally, bacteria can only produce a certain amount of butanol - perhaps 15g of the chemical for every litre of water in the tank - before the tank would become too toxic for the bacteria to survive, according to Shang-Tian Yang, professor of chemical and biomolecular engineering at Ohio State University.

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

Today, butanol is mainly used as a solvent or in industrial processes that make other chemicals. However, experts believe that this form of alcohol holds potential as a biofuel.

Once developed as a fuel, it could potentially be used in cars in place of petrol, while producing more energy than another alternative fuel, ethanol.