Dilute Acid Pretreatment and Enzymatic Hydrolysis of Woody Biomass for Biofuel Manufacturing: Effects of Particle Size on Sugar Conversion

Abstract

Biofuels derived from cellulosic biomass offer a promising alternative to petroleum-based liquid transportation fuels. Cellulosic biomass can be converted into biofuels through biochemical pathway. This pathway consists of two major conversions: sugar conversion and ethanol conversion. Sugar yield in sugar conversion is critical to the cost effectiveness of biofuel manufacturing, because it is approximately proportional to the ethanol biofuel yield. Cellulosic biomass sugar conversion consists of pretreatment and enzymatic hydrolysis. Biomass particle size is an important factor affecting sugar yield. The literature contains many studies investigating the relationship between particle size and sugar yield. Many studies focused only on the sugar yield in enzymatic hydrolysis, and failed to take into account the biomass weight loss during pretreatment. This weight loss results in a loss of the amount of potential sugar (cellulose), which continues going into enzymatic hydrolysis. Without considering this loss, cellulosic biomass with a higher enzymatic hydrolysis sugar yield may end up with a lower total sugar yield through sugar conversion. The present study aims to address this issue by investigating the effects of biomass particle size using total sugar yield, a parameter considering both the biomass weight loss in pretreatment and the sugar yield in enzymatic hydrolysis.