Biphasic 2-methyltetrahydrofuran/oxalic acid/water pretreatment to enhance cellulose enzymatic hydrolysis and lignin valorization

• Published in: Bioresource technology 2017-11, Vol.243, p.1105-1111
• Main Authors: Li, Shu-Xian, Li, Ming-Fei, Bian, Jing, Sun, Shao-Ni, Peng, Feng, Xue, Zhi-Min
• Format: Article
• Language: English
• Subjects: 2-Methyltetrahydrofuran; Bamboo; Biphasic pretreatment; Cellulose; Enzymatic hydrolysis; Furans; Hydrolysis; Lignin; Oxalic Acid; Water
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2017.07.075

[Display omitted] •Lignocellulose was pretreated by biphasic 2-MeTHF/oxalic acid/water system.•Cellulose conversion rate was enhanced by 6.7-fold during enzymatic hydrolysis.•The lignin obtained had a very low amount of contaminated sugars (0.67–2.39%).•The lignin exhibited representative structure (such as β-O-4, β-β linkages). A biphasic pretreatment was adopted to disturb the recalcitrant structure of bamboo for further enzymatic hydrolysis and to obtain easily valorized lignin by-product. The biphasic system consisted of biomass-derived chemicals—2-methyltetrahydrofuran and oxalic acid as well as water, and the reactions were conducted at 120–180°C for 20min. The treatment resulted in notable removal of hemicelluloses and lignin. After the pretreatment, the cellulose conversion rate during enzymatic hydrolysis was enhanced by 6.7-fold as compared to the unpretreated raw material. Comprehensive analysis of the lignin product indicated that it exhibited representative structure (such as β-O-4, β-β linkages) as compared to native lignin, contained a very low amount of contaminated sugars (0.67–2.39%), and had a relatively medium molecular weight (Mw 2240–3730g/mol) and good solubility in many organic solvents. This indicated that the lignin showed great potential application in conversion into materials and liquid fuels.