Enzymatic hydrolysis and fermentation for Afex treated corn stover - An integrated biorefinery approach

Corn stover was pretreated using optimal AFEX conditions, followed by enzymatic hydrolysis at varying glucan loadings (1-12%) in a fed batch process. At higher solid loadings, the increased concentration of inhibitors, i.e., lignin phenolics and organic acids, hindered enzyme and microbe performance. To reduce this inhibitory effect, several strategies were explored. Pretreated biomass was washed to remove pretreatment degradation products. Enzymatic hydrolysis was supplemented with protein rich additives. The sugar yield during the process and ethanol yield were shown by performing Pichia Stipitis fermentation. This is an abstract of a paper presented at the 2007 AIChE Annual Meeting (Salt Lake City, UT 11/4-9/2007).