Making Biomass Economically Viable
Wednesday, July 20 2011
Los Alamos researchers S. Gnanakaran, Giovanni Bellesia, and Paul Langan joined Shishir Chundawat and Bruce Dale of Michigan State University, along with collaborators from the Great Lakes Bioenergy Research Center, on a potential pretreatment method that can make plant cellulose five times more digestible by enzymes that convert it into ethanol, a useful biofuel.
Biomass is a desirable renewable energy source because fermentable sugars within the cellulose network of plant cells can be extracted with enzymes and then converted into ethanol. Yet a key difficulty in creating biofuels from plant matter is that the cellulose tends to orient itself into a sheet-like network of highly ordered, densely packed molecules. These sheets stack upon themselves and bond together tightly due to interactions between hydrogen atoms. This stacking and bonding arrangement prevents enzymes from directly attacking most of the individual cellulose molecules and isolating the sugar chains within them.
Currently, ethanol can only be extracted in usable quantities if the biomass is pretreated with costly, potentially toxic chemicals in an energy-intensive process. The research team has discovered a way to develop potentially cost-effective pretreatment methods that could make biomass an economically viable contender in the biofuels arena.