Shao Lupeng, Wang Chao, Liu Yu, Wang Meng, Wang Luyan, Xu Feng
State Key Laboratory of Biobased Material and Green Papermaking, Key Laboratory of Pulp and Paper Science & Technology (Ministry of Education), Qilu University of Technology (Shandong Academy of Sciences), Jinan, China.
Shandong Chenming Paper Holdings Co., Ltd., Weifang, China.
Front Bioeng Biotechnol. 2022 Dec 16;10:1082341. doi: 10.3389/fbioe.2022.1082341. eCollection 2022.
Lignin, an abundant aromatic biopolymer, has the potential to produce various biofuels and chemicals through biorefinery activities and is expected to benefit the future circular economy. Microwave-assisted efficient degradation of lignin in methanol/formic acid over Ru/C catalyst cooperated with metal chloride was investigated, concerning the effect of type and dosage of metal chloride, dosage of Ru/C, reaction temperature, and reaction time on depolymerized product yield and distribution. Results showed that 91.1 wt% yield of bio-oil including 13.4 wt% monomers was obtained under the optimum condition. Yields of guaiacol-type compounds and 2,3-dihydrobenzofuran were promoted in the presence of ZnCl. Formic acid played two roles: (1) acid-catalyzed cleavage of linkages; (2) acted as an hydrogen donor for hydrodeoxygenation in the presence of Ru/C. A possible mechanism for lignin degradation was proposed. This work will provide a beneficial approach for efficient depolymerization of lignin and controllable product distribution.
木质素是一种丰富的芳香族生物聚合物，有潜力通过生物精炼活动生产各种生物燃料和化学品，并有望为未来的循环经济带来益处。研究了在Ru/C催化剂与金属氯化物协同作用下，微波辅助甲醇/甲酸中木质素的高效降解，考察了金属氯化物的种类和用量、Ru/C用量、反应温度和反应时间对解聚产物收率和分布的影响。结果表明，在最佳条件下，生物油收率为91.1 wt%，其中单体含量为13.4 wt%。在ZnCl存在下，愈创木酚型化合物和2,3-二氢苯并呋喃的收率得到提高。甲酸起到了两个作用：（1）酸催化键的断裂；（2）在Ru/C存在下作为加氢脱氧的氢供体。提出了一种可能的木质素降解机理。这项工作将为木质素的高效解聚和可控产物分布提供有益的方法。
