A sequential combination of advanced oxidation and enzymatic hydrolysis reduces the enzymatic dosage for lignocellulose degradation

Abstract

High cellulase cost is a significant challenge to reducing the production cost of the lignocellulosic ethanol industry. Fenton reagents can oxidize and degrade organic matter through the advanced oxidation process. This study combined the Fenton reagent with cellulase to improve lignocellulose degradation efficiency and reduce the amount of enzyme dosage. Fenton reaction studies showed that the experimental group of 1000 mmol/L H2O2 + 10 mmol/L FeSO4 was the most suitable condition for coupled cellulase hydrolysis and excessive reagents might cause a decrease in the promotion effect. The solid loading analysis evidenced that the lignocellulose degradation can be facilitated by the Fenton reagent in the 15%–30% solids range. Treated with the Fenton reagent, the release of free water and the increase of specific surface area in the degradation process were enhanced. It's indicated that the amount of cellulase decreased by 76.2% under the combination of advanced oxidation and enzymatic hydrolysis. The techno-economic analysis of 300,000 t/a lignocellulosic ethanol showed that the combination reduced 26.96% annual costs. These results confirmed that the method of combining advanced oxidation with enzymatic hydrolysis is an effective way to improve the economics of industrial ethanol.