摘要
在101.32 kPa下,用改进的Othmer釜测定了含离子液体1-丁基-3-甲基四氟硼酸咪唑盐([BMIM]BF4)的异丁醇-水物系的等压汽液平衡数据。实验结果表明,当[BMIM]BF4的摩尔分数为10%时异丁醇-水二组分物系的汽液平衡线就开始偏离,[BMIM]BF4摩尔分数为20%,30%时,偏离程度越大;[BMIM]BF4表现出盐效应,使异丁醇对水的相对挥发度发生改变,消除了异丁醇-水物系的共沸点;[BMIM]BF4含量越大,盐效应越明显,随着[BMIM]BF4含量的增加,异丁醇对水的相对挥发度也随着增加。[BMIM]BF4可以做为异丁醇-水物系萃取精馏分离的有机盐,适宜的[BMIM]BF4摩尔分数为20%。
Isobaric vapor-liquid equilibrium data for the isobutanol -water system containing the ionic liquid （IL） 1-butyl-3-methylimidazolium tetrafluoroborate （[ BMIM] BF4） were measured in a modified Othmer still at 101.32 kPa. The vapor -liquid equilibrium curve for the isobutanol-water with added IL deviates from that of the binary system when the mole fraction of [ BMIM ] BF4 reaches 10%. When the mole fraction of [ BMIM ] BF4 is 20% or 30% , the deviation is greater. The IL shows a salt effect, which increases the volatility of isobutanol relative to that of water, and even leads to the disappearance of the azeotropic point. Increasing addition of [ BMIM ] BF4 results in the salt effect becoming more distinct, and the volatility of isobutanol relative to water increases. As a result, it is concluded that [ BMIM ] BF4 can be employed as a salt in the extractive distillation of the isobutanol - water system. The optimum mole fraction of [ BMIM ] BF4 is about 20%, and the VLE data obtained allow the design of the process to be optimized.
出处
《北京化工大学学报（自然科学版）》
CAS
CSCD
北大核心
2010年第2期25-29,共5页
Journal of Beijing University of Chemical Technology(Natural Science Edition)
基金
国家"863"计划(2006BAI09B07-01)
国家"973"计划(2007CB714304)
关键词
汽液平衡
离子液体
异丁醇
水
1-丁基-3-甲基四氟硼酸咪唑盐
vapor - liquid equilibrium
ionic liquids
isobutanol
water
1-butyl-3-methylimidazolium tetraflu- oroborate
