Affiliation:
1. School of Light Industry and Engineering South China University of Technology Guangzhou 510640 China
Abstract
AbstractConverting lignin into aromatic chemicals is a promising strategy for the high‐value utilization of lignocellulosic feedstock. However, the inherent heterogeneity of lignin poses a significant obstacle to achieving efficient conversion and optimal product yields within bio‐refinery systems. Herein, we employed a one‐step fractionation method to enhance lignin homogeneity and utilized the THF/DMSO‐EtONa (tetrahydrofuran/dimethyl sulfoxide‐sodium ethoxide) system to depolymerize the fractionated lignin. Three protic and three aprotic solvents were used for fractionation. The impact of the solvent properties on the structure and the depolymerization efficiency of the fractionated lignin was investigated. Methanol‐fractionated lignin generated the benzoic acid compounds with a yield of 30 wt%, 50 % higher than that of the unfractionated lignin. The polarities (δP), hydrogen bonding abilities (δH), and viscosities (η) of selected protic solvents showed strong linear correlation with molecular weight (Mw), polymer dispersity index (PDI), and syringyl/guaiacyl ratio (S/G ratio) of the fractionated lignin, as well as the total yield of benzoic acid compounds derived from the β‐O‐4 bond cleavage. This study elucidates the relationship between solvent properties and lignin structure and proposes a promising approach for refining lignin to enhance utilization efficiency, thereby presenting a potential strategy for value‐added application of complex lignin polymers.
Funder
Basic and Applied Basic Research Foundation of Guangdong Province
National Natural Science Foundation of China
Natural Science Foundation of Guangdong Province
Fundamental Research Funds for the Central Universities