Ethylene glycol based acid pretreatment of corn stover for cellulose enzymatic hydrolysis
Abstract
A highly efficient pretreatment strategy using ethylene glycol with dilute sulfuric acid was developed for the fractionation of lignocellulose. The pretreatment behaviors were related to the composition analysis and structure of the samples analyzed by SEM, XRD, FTIR and 2D HSQC NMR, resulting in 80.3% delignification and 84.7% retention of cellulose under the selected conditions (120 °C, 60 min, and 0.6 wt% H2SO4 (w/w)). The enzymatic hydrolysis sugar yield significantly increased from 24.1 to 70.6% (3 FPU g−1), which displayed immense improvement compared with untreated corn stover (24.1%), nearly 3-fold higher than its untreated counterparts. Besides, the regenerated lignin could be fitted to valorize renewable aromatic chemicals and alkane fuels. The present study shows that the pretreatment is a simple, efficient and promising process for corn stover biorefinery.