Conversion performance of blended and constituent corn stover and switchgrass using dilute-acid pretreatment and enzymatic hydrolysis

A preliminary assessment of resource availability (including energy crops, like sorghum and energy cane) over the entire U.S. indicates that feedstock blending has the potential to expand the resource pool for biofuel production by an estimated 31% over corn stover alone. Formulation and blending contribute to achieving sustainable biofuel production by coupling location-specific resource usage to the generation of feedstocks with enhanced supply-chain stability and acceptable compositional quality. Compositional analysis, dilute-acid pretreatment and enzymatic hydrolysis were used to assess conversion performance of corn stover (CS) and switchgrass (SWG) blends at ratios of 50/50, 60/40, 70/30, 80/20, and 90/10, respectively. Ternary blends of CS, SWG, and sorghum or energy cane (65/30/5) were also examined. There were no significant differences in glucose and xylose yields from combined pretreatment and enzymatic hydrolysis for blends relative to CS alone. Blending allows a feedstock with lower potential yields to enter the resource pool to meet compositional quality. Blends that are capable of achieving similar yields to corn stover have the potential to expand the pool of available resources for biofuel production.