Researchers at Iowa State University are developing a system of thermochemical and catalytic technologies to produce ethanol from plant biomass.
The Iowa State project is being led by Victor Lin, a professor of chemistry and director of the Center for Catalysis.
In the project, the research team is working to develop a biomass-to-ethanol system that would work like this: Plant biomass such as corn stalks and switchgrass would be broken down by fast pyrolysis, a process that uses heat at 900 degrees Fahrenheit in the absence of oxygen to convert biomass into a bio-oil.
The bio-oil would be gasified with steam and/or oxygen at 1,100 to 1,500 degrees Fahrenheit to produce a synthesis gas, a mixture of carbon monoxide, hydrogen, carbon dioxide and short-chain hydrocarbon gases. The hydrogen and carbon monoxide in the synthesis gas would be reacted with a nanotechnology-based catalyst to produce ethanol fuel.
Lin said that the researchers involved in the project have looked at catalysts to produce ethanol from synthesis gas for years. But there were some problems with the old chemistry and research progress has slowed since the early 1990s. The chemistry didn't produce the selective reactions necessary for efficient production. There were also issues with controlling those reactions.
But now, "With the emphasis on biomass and biorenewables, I think there will be a renaissance of this research and technology," Lin said.
Satrio, of Iowa State's Center for Sustainable Environmental Technologies, called the research collaboration "a very exciting project. This is on the cutting edge of this technology."
The center's focus will be to develop a system that efficiently and economically produces clean synthesis gas that's ready to be reacted with Lin's catalyst.
Center researchers will use the two thermochemical technologies (fast pyrolysis and gasification) with the goal of developing a complete conversion system that makes economic sense for the future.
The Iowa State idea calls for biomass to be transported to small, local fast pyrolysis plants that would convert the plant fiber into liquid bio-oil, Satrio said.