基于COSMO-RS模型研究基团修饰[EMIM][OAC]的离子液体对乙腈-水汽液平衡的影响.pdfVIP

2016 年 2 月 CIESC Journal ·425· February 2016 第 67卷 第 2期 化 工 学 报 Vol.67 No.2 基于 COSMO-RS 模型研究基团修饰[EMIM][OAC]的离子液体 对乙腈-水汽液平衡的影响 李婷婷，杨青，彭昌军，刘洪来 （华东理工大学化学系，化学工程联合国家重点实验室，上海 200237） 摘要：以 1-乙基-3-甲基咪唑醋酸盐（[EMIM][OAC]）为基准，通过分别在阴阳离子上修饰胺基(—NH2)、羟 基 (—OH)、腈基(—CN)、卤素(Br、F)等，虚拟设计了 15 种阳离子和 21 种阴离子组成的离子液体（IL）。采用基 于 COSMO-RS 模型的 COSMOthermX 软件计算了所设计的离子液体对乙腈-水混合物恒压汽液相平衡的影响，探 索了修饰基团的种类、离子液体结构对乙腈相对挥发度的影响规律。研究发现，在阳离子碳链上修饰—NH2，阴 离子（醋酸根和丙酸根）羰基的邻碳上进行单一的—OH 修饰能促进乙腈与水的分离，且阳离子修饰的—NH2 数 越多，促进分离的效果越明显，其他嫁接方式未取得好的分离效果。虚拟设计的两种阳离子（1-胺乙基-3-甲基咪 唑、2,2,2-三胺乙基-3-甲基咪唑）与 3 种阴离子（羟基乙酸、2-羟基丙酸、2-羟基-3-胺基丙酸）组合的离子液体分 离效果明显比[EMIM][OAC]好。 关键词：离子液体；COSMO-RS；乙腈；水；汽液相平衡 DOI：10.11949/j.issn.0438-1157 中图分类号：TQ 013.1 文献标志码：A 文章编号：0438—1157（2016）02—0425—10 Functionalized ionic liquids based on [EMIM][OAC] for vapor-liquid phase equilibrium of acetonitrile and water by COSMO-RS method LI Tingting, YANG Qing, PENG Changjun, LIU Honglai (State Key Laboratory of Chemical Engineering, Department of Chemistry, East China University of Science and Technology, Shanghai 200237, China) Abstract：Based on 1-ethyl-3-methylimidazolium acetate ([EMIM][OAC]), ionic liquids composed by 15 cations and 21 anions were designed by modifying [OAC] and [EMIM] with different groups, including amine (—NH2), hydroxy (—OH), nitrile (—CN), halogen (Br, F) and so on. The effect of the designed ionic liquids on the vapor-liquid phase equilibrium of acetonitrile and water mixtures was predicted by COSMOthermX based on COSMO-RS model. The influence of group type and IL structure on relative volatility of acetonitrile was also investigated. The results showed that the ILs carrying —NH2 in cation or carrying —OH in anion can promote the separation of acetonitrile from water and the separation effect becomes more obvious with increasing number of — NH2