离子液体萃取分离石脑油中芳烃的理论计算与试验验证  

Theoretical calculation and experimental verification of aromatics extraction from naphtha by ionic liquids

作　　者：徐春明[1] 殷梦凡 童浩 车培源 张睿[1] 刘海燕[1] 刘植昌[1] 张霖宙 孟祥海[1] XU Chunming;YIN Mengfan;TONG Hao;CHE Peiyuan;ZHANG Rui;LIU Haiyan;LIU Zhichang;ZHANG Linzhou;MENG Xianghai(State Key Laboratory of Heavy Oil Processing in China University of Petroleum(Beijing),Beijing 102249,China)

机构地区：[1]中国石油大学(北京)重质油全国重点实验室,北京102249

出　　处：《中国石油大学学报（自然科学版）》2023年第5期138-145,共8页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家自然科学基金项目(22021004,22078359)。

摘　　要：以苯-环己烷为模型体系,基于COSMO-RS模型研究多种离子液体阴、阳离子对分离性能的影响,以萃取性能指数作为评价指标优选出1-丁基-3-甲基咪唑四氯化铁([Bmim][FeCl_(4)])萃取剂,并对[Bmim][FeCl_(4)]与苯、环己烷的弱相互作用进行探究。合成[Bmim][FeCl_(4)]离子液体,并用于苯-环己烷体系的萃取分离,证实该离子液体对石脑油中的芳烃具有良好的萃取分离效果,采用NRTL模型对[Bmim][FeCl_(4)]-苯-环己烷体系的二元交互作用参数进行拟合。结果表明:离子液体[Bmim][FeCl_(4)]选择性萃取分离芳烃主要依靠咪唑阳离子与芳烃之间的π-π相互作用;相较于环丁砜,该离子液体对于苯-环己烷体系具有更大的两相区,易于苯-环己烷体系的分离;针对芳烃质量分数为0.1的原料,其芳烃分配系数、萃取选择性、萃取性能指数分别可达0.770、19.73和15.19;NRTL模型对该三元体系预测效果较好,均方根偏差为1.14%。The benzene-cyclohexane was used as model system to study the effect of various anions and cations of ionic liquids on the separation performance of benzene-cyclohexane system through COSMO-RS model.The extraction performance index was used as an evaluation indicator to select the optimal ionic liquid of 1-butyl-3-methylimidazole ferric tetrachloride([Bmim][FeCl_(4)]).Then the weak interaction of[Bmim][FeCl_(4)]with benzene and cyclohexane was investigated.The ionic liquid[Bmim][FeCl_(4)]was synthesized and used for the extraction and separation of benzene-cyclohexane system.It is proved that the ionic liquid has a good extraction and separation effect on aromatics from naphtha.The binary interaction parameters of[Bmim][FeCl_(4)]-benzene-cyclohexane system were fitted by NRTL model.The results show that the selective extraction of aromatic hydrocarbon by ionic liquid[Bmim][FeCl_(4)]mainly depends on the π-π interaction between imidazole cation and aromatic hydrocarbon.Compared with sulfolane,the system shows a larger two-phase region with ionic liquid,which is helpful to separate benzene-cyclohexane.For the raw material with 0.1 aromatic hydrocarbon,the distribution coefficient,extraction selectivity and extraction performance index of aromatic hydrocarbon could reach 0.770,19.73 and 15.19,respectively.In addition,the NRTL model has a good prediction effect on the ternary system,and the root-mean-square deviation is 1.14%.

关 键 词：离子液体 石脑油 萃取 芳烃 分离 

分 类 号：TQ028[化学工程]