Ethanol production from bamboo using mild alkaline pre-extraction followed by alkaline hydrogen peroxide pretreatment. (January 2018)

• Record Type: Journal Article
• Authors: Yuan, Zhaoyang; Wen, Yangbing; Kapu, Nuwan Sella
• Is Part Of: Bioresource technology. Volume 247(2018)
• Page Start: 242
• Page End: 249
• Publication Date: 2018-01
• Subjects: Alkaline hydrogen peroxide -- Alkaline pretreatment -- Bamboo -- Biorefinery -- Enzymatic hydrolysis -- Ethanol; 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.2017.09.080
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Sequential alkali extraction-AHP treatment enabled efficient bamboo fractionation. The proposed process produces ethanol and recovers lignin and silica. Compared to traditional one-stage AHP, H2 O2 demand could be substantially lowered. High ethanol titer was reached with relatively low enzyme loadings. Abstract: A sequential two-stage pretreatment process comprising alkaline pre-extraction and alkaline hydrogen peroxide pretreatment (AHP) was investigated to convert bamboo carbohydrates into bioethanol. The results showed that mild alkaline pre-extraction using 8% (w/w) sodium hydroxide (NaOH) at 100 °C for 180 min followed by AHP pretreatment with 4% (w/w) hydrogen peroxide (H2 O2 ) was sufficient to generate a substrate that could be efficiently digested with low enzyme loadings. Moreover, alkali pre-extraction enabled the use of lower H2 O2 charges in AHP treatment. Two-stage pretreatment followed by enzymatic hydrolysis with only 9 FPU/g cellulose led to the recovery of 87% of the original sugars in the raw feedstock. The use of the pentose-hexose fermenting Saccharomyces cerevisiae SR8u strain enabled the utilization of 95.7% sugars in the hydrolysate to reach 4.6% w/v ethanol titer. The overall process also enabled the recovery of 62.9% lignin and 93.8% silica at high levels of purity.