甲醇-甲乙酮-1-辛基-3-甲基咪唑六氟磷酸盐物系等压汽液平衡数据的测定

Vapor-liquid equilibria for the methanol-methyl ethyl ketone-1-octyl-3-methylimidazolium hexafluorophosphate ([OMIM]PF_6) system

在101.3 kPa下,用改进的Othmer釜测定了含摩尔分数分别为5%、8%、10%和20%离子液体1-辛基-3-甲基咪唑六氟磷酸盐([OMIM]PF6)的甲醇-甲乙酮-[OMIM]PF6汽液平衡数据,并采用NRTL方程进行关联。实验结果表明,当离子液体[OMIM]PF6的摩尔分数为5%时,甲醇-甲乙酮二组分物系汽液平衡线发生偏离,当离子液体[OMIM]PF6摩尔分数达到8%时,就可以消除甲醇-甲乙酮物系的共沸点;离子液体[OMIM]PF6摩尔分数越大,盐效应越明显,离子液体[OMIM]PF6可以作为甲醇-甲乙酮的萃取剂。

Isobaric vapor- liquid equilibrium(VLE) data for the methanol- methyl ethyl ketone(MEK) system containing 1-octyl-3-methylimidazolium hexafluorophosphate([OMIM]PF 6) with varying mole fractions of 5%, 8%,10% and 20% at 101. 3 kPa have been measured in a modified Othmer still. The VLE data were fitted with the NRTL model. The vapor- liquid equilibrium curves of methanol- MEK with [OMIM]PF 6 deviate from that without [OMIM]PF 6. The azeotropic point disappeared when the mole fraction of [OMIM]PF 6 was 8%,and higher mole fractions of [OMIM]PF 6 led to an increasing salt effect. The results show that [OMIM]PF 6 is a suitable solvent for extractive distillation of the methanol-MEK system.