离子液体对模拟生物质原料组分的选择性分离

Selective Separation of Components from a Model Lignocellulose by Using Ionic Liquids

设计合成了一系列咪唑基羧酸盐离子液体:1丁基3甲基咪唑甲酸盐,1丁基3甲基咪唑乙酸盐,1丁基3甲基咪唑乳酸盐,1丁基3甲基咪唑乙醇酸盐,1丁基3甲基咪唑苯甲酸盐和1丁基3甲基咪唑二氰胺盐,并采用氢核磁方法对这些离子液体进行了表征和结构确认。研究了离子液体的阴离子结构、体系溶解温度对木质素和木聚糖溶解度的影响。根据不同离子液体对纤维素、木聚糖、木质素溶解性能的差异,实现了模拟生物质原料3个组分的选择性逐级分离,木质素、木聚糖和纤维素的分离质量分数分别为76.9%、75.4%和99.3%。离子液体[C4mim][N(CN)2]的回收质量分数为89.6%。

In this paper,a series of carboxylate ionic liquids(ILs) including 1butyl3methylimidazolium formate,1butyl3methylimidazolium acetate,1butyl3methylimidazolium lactate,1butyl3methylimidazolium glycollate,1butyl3methylimidazolium benzoate and 1butyl3methylimidazolium dicyanamide were synthesized.The ionic liquids were characterized by means of 1H NMR spectra.The effects of anionic structure of the ILs and temperature of the system on the solubilities of xylan and lignin were investigated.Based on the difference in the solubility of cellulose,xylan and lignin in the ILs,the selective separation of the three components from a model lignocellulose was conducted.The weight percentage of the separated lignin,xylan and cellulose was 76.9%,75.4% and 99.3%,respectively.In addition,the recovery of the IL[N(CN)2] were investigated as well,and the recovered weight percentage of [N(CN)2]was 89.6%.