Washington: Researchers are combining traditional gassification with high-tech nano-catalysts to extract ethanol from a range of biomass, which includes wood pulp, animal waste and residual distillers' grain.

Gasification is a process that converts carbon-based feedstocks under high temperature and pressure in an oxygen-controlled atmosphere into synthesis gas, or 'syngas'.

Syngas is made up of carbon monoxide and hydrogen (85 percent by volume) and smaller quantities of carbon dioxide and methane.

It's basically the same technique that extracted gas from coal fuelled gas light fixtures prior to the light bulb. The advantage of gassification compared to fermentation technologies is that it can be used in a variety of applications, including process heat, electric power generation, and synthesis of commodity chemicals and fuels.

"There was some interest in converting syngas into ethanol during the first oil crisis back in the 70s," said US Department of Energy's Ames Lab chemist Victor Lin.

"The problem was that catalysis technology at that time didn't allow selectivity in the byproducts. They could produce ethanol, but you'd also get methane, aldehydes and a number of other undesirable products."

A catalyst is a material that facilitates and speeds up a chemical reaction without changing itself. In studying the chemical reactions in syngas conversion, Lin found that the carbon monoxide molecules that yielded ethanol could be "activated" in the presence of a catalyst with a unique structural feature, overcoming the earlier problems.