Production of xylose, xylulose, xylitol, and bioethanol from waste bamboo using hydrogen peroxicde-acetic acid pretreatment

Abstract

Bioethanol is a typical product of biorefineries, and an alternative to fossil fuels, which increase greenhouse gas emission levels. However, high production costs hinder the widespread adoption of bioethanol refineries. Co-production of bioethanol and other value added by-products from waste biomass is an effective strategy to improve the cost competitiveness of bioethanol production. Disruption of the lignin structure in waste bamboo via hydrogen peroxide-acetic acid (HPAC) pretreatment improved the efficiency of the hydrolysis more than six times compared to hydrolysis without pretreatment. HPAC-pretreatment yielded no significant difference between separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) processes in terms of the productivity of ethanol fermentation with optimized enzyme doses In contrast, the productivity of xylose was higher with SHF rather than SSF. Both products were successfully separated using a polydimethylsiloxane/polyetherimide (PDMS/PEI) hollow-fiber membrane. Co-production of xylose and bioethanol improved cost-competitiveness by simultaneous conversion processes for the co-production of xylulose and xylitol as value added byproducts.