Efficient separation of bagasse lignin by freeze–thaw-assisted p-toluenesulfonic acid pretreatment

• DOI: 10.1016/j.biortech.2022.126951
• Publication Date: 2022-03-05T07:06:15Z
• Authors: Huali Zeng; Baojie Liu; Jiao Li; Mei Li; Meijiao Peng; Chengrong Qin; Chen Liang; Caoxing Huang; Xinping Li; Shuangquan Yao
• Keywords: Bagasse; p-Toluenesulfonic acid; Lignocellulosic Biomass

Lignin separation is an important procedure that benefits multiple industries and in particular biomass transformation efforts. In this study, bagasse lignin was separated by freeze-thaw-assisted p-toluenesulfonic acid (p-TsOH) pretreatment. The optimal conditions were freezing temperature -60 °C, freezing time 8.0 h, thawing temperature 15 °C, p-TsOH concentration 60%, pretreatment temperature 70 °C, and time 20 min. Lower acid concentrations and temperatures were used compared with traditional p-TsOH pretreatment. The efficiency and selectivity of lignin separation were improved. It was attributed to freeze-thawing, which provided a more efficient physical channel for the effective penetration of p-TsOH. The separation, extraction and purity of lignin were improved to 89.76%, 78.22% and 77.89%, respectively. High separation, high extraction, high purity and large molecular weight lignin samples were obtained. In addition, the recovery and reuse of p-TsOH was enhanced. This provided a new method for the efficient and clean separation of lignin.