胆碱类低共熔溶剂选择性分离杨木中木质素的研究

Selective Extraction of Poplar Lignin with Choline-based Deep Eutectic Solvents

关键词:  低共熔溶剂  杨木  木质素  选择性分离

Key Words:deep eutectic solvent  poplar  lignin  selective extraction solvent

摘要:本研究使用多种胆碱类低共熔溶剂（DES）选择性分离杨木中的木质素，探究了不同氢键供体及其含量对木质素分离效果的影响。结果表明，氯化胆碱-乳酸（ChCl-Lac）在摩尔比1∶10配比下木质素分离效果最佳，综纤维素得率为46.26%，木质素提取率为84.38%，木质素纯度为89.82%。经过改性后新型DES乳酸胆碱-乳酸(ChLac-Lac)（摩尔比1:10）分离效果更佳，综纤维素得率为48.16%，木质素提取率为90.13%，木质素纯度为90.29%。与磨木木质素相比，ChCl-Lac和ChLac-Lac提取的木质素具有纯度高、杂质少、热稳定性好、相对分子质量低、分布窄的特性。

Abstract:Choline-based deep eutectic solvents (DES) were used to selectively extract lignin from poplar. The effect of variations of hydrogen bond donor and the ratio of hydrogen bond donor and hydrogen bond acceptor on the efficiency of lignin extraction was investigated. The results showed that the yield of holocellulose was 46.26%，lignin extraction rate of 84.38%, and the lignin purity was 89.82% at ChCl-Lac ratio of 1∶10. The new type ChLac-Lac DES had better selectivity, at the ratio of ChLac-Lac was 1∶10，the yield of holocellulose was 48.16%，lignin extraction rate was 90.13%, while the lignin purity was 90.29%. Compared to milled lignin, the lignin extracted by ChCl-Lac DES and ChLac-Lac DES presented higher purity，better thermal stability, lower molecular weight and narrower distribution, which could be used for the production of high value-added chemicals.