(3ap) Ionic Liquid Pretreatment Technology: Effects of Pretreatment Conditions On Biomass Structure, Composition, and Enzymatic Digestibility

Rising fuel costs due to the high costs of oil has driven the demand for alternative energy.  One of the many alternative energy sources that have been studied over the past years has been biofuels derived from lignocellulosic biomass instead of from corn.  This change in biofuel feedstock is driven by opportunity costs associated with corn as fuel or food.  Lignocellulosic biomass is an abundant source of carbon consisting of three major components:  cellulose, hemicellulose, and lignin.  Because it is non-food based feedstock, lignocellulosic biomass serves as a renewable carbon source while mitigating impact on food supply.  Monomeric sugars can be produced through a biochemical process which includes pretreatment of the biomass to produce a more easily hydrolyzed substrate and enzymatic deconstruction of polysaccharides to monomeric sugars.  These sugars can then be used in the production of fuels and value-added chemicals through fermentation or chemical conversion.

During my tenure at The University of Toledo, I have been examining the mechanisms of the ionic liquid (IL) pretreatment technology as well as enzymatic saccharification of pretreated biomass as they relate to monomeric sugar production for future chemical and biofuel processing. As part of this research, we have used X-ray powder diffraction and fiber diffraction crystallography to determine the post-pretreatment cellulose structure in order to determine its effect on enzymatic digestibility.  Additionally, we examined the roles of different enzymatic activities during the deconstruction of IL pretreated biomass by using tailored enzyme mixtures containing known quantities of purified and characterized mono-component enzymes.  This knowledge of required enzymatic activity can lead to a reduction in the amount and, ultimately, costs of the enzymatic portion of the biofuels process.