六氟磷酸盐对碳酸二甲酯-甲醇相平衡的影响  

Effect of hexafluorophosphate on phase equilibrium of dimethyl carbonate-methanol system

作　　者：曹江风 曹玲[1] 李学琴[1] CAO Jiang-feng;CAO Ling;LI Xue-qin(Department of Chemistry and Applied Chemistry,College of Changji,Changji 831100,Xinjiang,China)

机构地区：[1]昌吉学院化学与应用化学系,新疆昌吉831100

出　　处：《化学工程》2020年第3期48-51,78,共5页Chemical Engineering(China)

基　　金：2017年度自治区高校科研计划项目(XJEDU2017M040)。

摘　　要：为验证1-丁基-3-甲基咪唑六氟磷酸盐([BMIM][PF6])和1-辛基-3-甲基咪唑六氟磷酸盐([OMIM][PF6])作为分离碳酸二甲酯+甲醇共沸体系萃取剂的可行性,在101.3 kPa下,用改进的Othmer釜测定了(甲醇+碳酸二甲酯+[BMIM][PF6])和(甲醇+碳酸二甲酯+[OMIM][PF6])的汽液平衡数据。用NRTL模型对汽液平衡实验数据进行了关联。实验结果表明:六氟磷酸阴离子液体的加入,使甲醇对碳酸二甲酯的相对挥发度增加,甲醇+碳酸二甲酯体系共沸点消失。在较高的甲醇摩尔分数下,[OMIM][PF6]对甲醇的盐析作用略强于[BMIM][PF6]。NRTL模型关联得出二元交互作用参数,可用于[BMIM][PF6]和[OMIM][PF6]分离碳酸二甲酯-甲醇物系的设计计算。To verify the feasibility of 1-butyl-3-methylimidazolium hexafluorophosphate([PF6])and 1-octyl-3-methylimidazolium hexafluorophosphate([OMIM][PF6])as extractants for the separation of dimethyl carbonate and methanol system,the vapor-liquid equilibrium data for(methanol+dimethyl carbonate+[PF6])and(methanol+dimethyl carbonate+[OMIM][PF6])at 101.3 kPa were measured with a modified Othmer still.The NRTL model was used for fitting the experimental data.The hexafluorophosphate-based anion ionic liquids can enhance the relative volatility of methanol to dimethyl carbonate.The azeotropic point of methanol+dimethyl carbonate system disappears with adding the hexafluorophosphate-based anion ionic liquids.The salting-out effect on the methanol produced by the[OMIM][PF6]is slightly stronger than that produced by[PF6]at higher methanol mole fractions.The binary interaction parameters obtained by NRTL model correlation can be used to design and calculate the process of separating the dimethyl carbonate-methanol mixture using[PF 6]and[OMIM][PF 6]as extractants.

关 键 词：碳酸二甲酯 甲醇 1-丁基-3-甲基咪唑六氟磷酸盐 1-辛基-3-甲基咪唑六氟磷酸盐 NRTL模型 

分 类 号：TQ013.1[化学工程]