Optimization of ethanol-extracted lignin from palm fiber by response surface methodology and preparation of activated carbon fiber for dehumidification

• Published in: Bioresources and bioprocessing Vol. 9; no. 1; p. 61
• Main Authors: Fan, Jie, Yu, Qiongfen, Li, Ming, Chen, Jie, Wang, Yunfeng, Zhang, Ying, Li, Guoliang, Ma, Xun, Zhong, Hao, Yu, Yamei
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 30.05.2022; Springer Nature B.V; SpringerOpen
• Subjects: Activated carbon; Biochemical Engineering; Carbon fibers; Chemistry; Chemistry and Materials Science; Dehumidification; Environmental Engineering/Biotechnology; Ethanol; Industrial and Production Engineering; Lignin; Lignin extraction; Lignin-based activated carbon fiber; Lignocellulose; Optimization; Organic solvent; Palm fiber; Process parameters; Response surface methodology; Solvent recycling; Organic solvent; Lignin extraction; Water vapor adsorption; Solvent recycling; Response surface methodology; Palm fiber; Lignin-based activated carbon fiber
• ISSN: 2197-4365; 2197-4365
• DOI: 10.1186/s40643-022-00549-9

Lignin is a renewable bioresource that can be used for a variety of value-added applications. However, the effective separation of lignin from lignocellulosic biomass remains an ongoing challenge. In this study, lignin was extracted from waste palm fiber and successfully converted into a dehumidifying material. The following four process parameters of lignin extraction from palm fiber were optimized systematically and comprehensively using the response surface methodology: reaction time, extraction temperature, ethanol concentration and solid/liquid ratio. The results revealed that under the optimum processing conditions (111 min of extraction at 174 °C using 73% ethanol at 1/16 g/mL solid/liquid ratio), the extraction yield of lignin was 56.2%. The recovery of ethanol solvent was as high as 91.8%. Further, the lignin could be directly used without purification to produce lignin-based activated carbon fibers (LACFs) with specific surface area and total pore volume of 1375 m 2 /g and 0.881 cm 3 /g, respectively. Compared with the commercial pitch-based activated carbon fiber, the LACF has a higher specific area and superior pore structure parameters. This work provides a feasible route for extracting lignin from natural palm fiber and demonstrates its use in the preparation of activated carbon fiber with a remarkable performance as a solid dehumidification agent. Graphical Abstract