Ethylene glycol based acid pretreatment of corn stover for cellulose enzymatic hydrolysis

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 degrees 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.

Automated summary

The study demonstrates that pretreatment using ethylene glycol and dilute sulfuric acid for lignocellulose fractionation is a simple, efficient, and promising process for corn stover biorefinery. Delignification and cellulose retention rates are high, leading to a significant increase in enzymatic hydrolysis sugar yield compared to untreated corn stover. The regenerated lignin can also be utilized to produce renewable aromatic chemicals and alkane fuels.