Using a combined hydrolysis factor to balance enzymatic saccharification and the structural characteristics of lignin during pretreatment of Hybrid poplar with a fully recyclable solid acid

• Published in: Bioresource technology 2017-08, Vol.238, p.575-581
• Main Authors: Ji, Hairui, Song, Yanliang, Zhang, Xu, Tan, Tianwei
• Format: Article
• Language: English
• Subjects: Biomass; Cellulose; Combined hydrolysis factor; Enzymatic saccharification; Fully recyclable solid acid; Hydrolysis; Lignin; Populus; Spectroscopy, Fourier Transform Infrared
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2017.04.092

•A new pretreatment strategy for lignocellulose with a fully recyclable solid acid was developed.•This pretreatment method greatly facilitates the enzymatic saccharification of the substrates.•The structural characteristic of residual lignin was comprehensively elucidated.•A CHF as a pretreatment severity was used to balance enzymatic hydrolysis and lignin structure. In this study, a new pretreatment strategy for lignocellulosic was developed using a fully recyclable solid acid, Toluenesulfonic acid (p-TsOH). A combined hydrolysis factor (CHF) as a pretreatment severity was used to balance enzymatic saccharification and the structural characteristics of lignin. The results from degradation of carbohydrates, enzymatic hydrolysis of cellulose and characterization of lignin by FT-IR, 31P NMR, GPC, 2D-HSQC NMR indicated that a CHF of approximately 3.90 was the optimal pretreatment severity to facilitate enzymatic saccharification and the potential serviceability of lignin. Then approximately 90% of the xylan was removed to result in a reasonable sugar yield of 76%. Residual lignin showed low molecular weight (Mw, 5783g/mol), narrow polydispersities (Mw/Mn, 1.10) and high content of phenolic hydroxyl groups (3.702mmol/g); it may be a potential feedstock for phenol monomer and polymeric materials production. In short, this process was regarded as a promising approach to achieve an efficient conversion of lignocellulosic biomass to sugar products and lignin-based materials.