ENZYMATIC HYDROLYSIS OF CORN STOVER PRETREATED BY COMBINED DILUTE ALKALINE TREATMENT AND HOMOGENIZATION

Abstract

Corn stover, the most abundant agricultural residue in the U.S., is a potential feedstock for production of bioethanolbecause of its high content of carbohydrates, but an efficient pretreatment is required prior to enzymatic hydrolysis. Inthis study, a combination of NaOH treatment and homogenization was used as a pretreatment to enhance the enzymatic hydrolysisof corn stover. The combined pretreatment increased the enzymatic hydrolysis of corn stover five times compared to thecontrol. The effectiveness of such pretreatment was found to be a function of NaOH concentration and particle size. Withinthe NaOH concentration range of 0.1 to 1.0 N, best performance of this combined pretreatment was achieved at 0.3 N NaOH.There is a significant cross effect of homogenization and NaOH treatment. Among the three particle sizes tested (the particlesize was not directly measured; it passed through screens with openings of 2 mm, 0.707 mm, and 0.25 mm respectively), 2 mmwas found to maximize the economic benefit of the pretreatment.