Researchers Developing Optimized Catalyst for Thermochemical Waste-to-Ethanol Production

16 August 2008

Researchers at the US Department of Energy’s Ames Laboratory and Iowa State University are developing new nanoscale porous catalysts to produce ethanol with high selectivity from a wide range gasified biomass, including distiller’s grain left over from ethanol production, corn stover from the field, grass, wood pulp, animal waste, and garbage.

There was some interest in converting syngas into ethanol during the first oil crisis back in the 70s. 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.

—Victor Lin, Ames Lab chemist and Chemical and Biological Science Program Director

Transmission electron micrograph (TEM) of the mesoporous silica nanospheres, with the nano-scale catalyst particles show up as the dark spots. Using particles this small (~ 3 nm) increases the overall surface area of the catalyst by roughly 100 times. Click to enlarge.

In studying the chemical reactions in the conversion of syngas to ethanol, Ames Lab chemist and Chemical and Biological Science Program Director Victor Lin found that the carbon monoxide molecules that yielded ethanol could be activated in the presence of a catalyst with a unique structural feature.

To increase the surface area of the metal alloy used as the catalyst, Lin’s group used nanoscale catalyst particles dispersed widely within the structure of mesoporous silica nanospheres (MSN). The total surface area of these dispersed catalyst nanoparticles is roughly 100 times greater than the surface area of catalyst material in larger, macro-scale particles.

The research is funded by the DOE’s Offices of Basic Energy Sciences and Energy Efficiency and Renewable Energy.

Lin’s group had previously developed a mesoporous silica nanosphere (MSN)-based catalyst designed to make the production of biodiesel less expensive, faster, and more flexible with respect to feedstock oils. Catilin, a start-up funded by Mohr Davidow Ventures, is seeking to commercialize that catalyst. (Earlier post.)