Finnish researchers develop cellulosic butanol process

By Erin Voegele | December 23, 2011

Researchers at Finland’s Aalto University have developed and patented a method to produce butanol and other industrial chemicals from woody biomass. According to information released by the university, the method involves the use of an altered pulping process that results in sugars that can be converted into these materials by microbes.

Information on the development released by Aalto University stated that most biobutanol production methods developed to date focus on the use of starch or cane sugar as feedstocks. The researchers leading this project have been able to overcome that limitation and develop a method that allows for the use of lignocellulosic feedstocks for the production of butanol.

Wood is primarily comprised of cellulose, hemicelluloses and lignin, with cellulose and hemicelluloses having the ability to serve as feedstocks for microbial conversion processes. The researchers state that the kraft process currently employed in wood pulping operations results in cellulose and black liquor, which cannot be used as a feedstock for microbial conversions. To complete the study, the university said that the existing pulping process was altered in a way that allows both cellulose and the other sugars contained in woody biomass to be extracted in a way that allows them to be converted into butanol and other chemicals by microbes.

“When wood biomass is boiled in a mixture of water, alcohol and sulfur dioxide, all parts of the wood—cellulose, hemicellulose and lignin—are separated into clean fractions,” said Aalto University in a press release announcing the achievement. “The cellulose can be used to make paper, nanocellulose or other products, while the hemicellulose is efficient microbe raw material for chemical production.  Thus, the advantage of this new process is that no parts of the wood sugar are wasted.”

The research has been led by Aalto University professors Adriaan van Heiningen and Tom Granström. Results of the study have been published in the peer reviewed journal Bioresource Technology.

According the university’s announcement, the research is part of the Finnish Funding Agency for Technology and Innovation’s BioRefine program, which aims to increase the refining value of forest residues.