An integrated process to produce bio-ethanol and xylooligosaccharides rich in xylobiose and xylotriose from high ash content waste wheat straw. (October 2017)

• Record Type: Journal Article
• Authors: Huang, Chen; Lai, Chenhuan; Wu, Xinxing; Huang, Yang; He, Juan; Huang, Caoxing; Li, Xin; Yong, Qiang
• Is Part Of: Bioresource technology. Volume 241(2017)
• Page Start: 228
• Page End: 235
• Publication Date: 2017-10
• Subjects: Waste wheat straw -- Bio-ethanol -- Xylooligosaccharides -- Prewashing -- Liquid hot water pretreatment; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2017.05.109
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: An integrated process for bio-ethanol and XOS productions from straw pulping residue. Prewashing step greatly improved enzymatic glucose yield and XOS content. Highly similar ethanol yields were obtained from SSF at varied substrate loadings. Enzymatic post-hydrolysis significantly increased xylobiose and xylotriose. Abstract: A bio-refinery process of wheat straw pulping solid residue (waste wheat straw, WWS) was established by combining prewashing and liquid hot water pretreatment (LHWP). The results showed that employing a prewashing step prior to the LHWP remarkably improved enzymatic glucose yields from 39.7% to 76.6%. Moreover, after 96 h simultaneous saccharification and fermentation (SSF), identical ethanol yields of 0.41 g/g-cellulose were obtained despite varied solid loadings (5–30%). Beyond ethanol, enzymatic post-hydrolysis of the prehydrolyzate effectively increased xylobiose and xylotriose yields from 15 mg/g-WWS and 14 mg/g-WWS to 53 mg/g-WWS and 20 mg/g-WWS, respectively. For mass balance, about 10.9 tons raw WWS will be consumed to produce 1 ton ethanol, in addition to producing 614.8 kg xylooligosaccharides (XOS) containing 334.3 kg xylobiose and 124.8 kg xylotriose. The results demonstrated that the integrated process for the WWS bio-refinery is promising, based on value-adding co-production in addition to robust ethanol yields.