乙酸甲酯-甲醇-1-乙基-3-甲基咪唑四氟硼酸盐物系等压汽液平衡数据的测定与关联

在101.3kPa下,用改进的Othmer釜测定了乙酸甲酯-甲醇-1-乙基-3-甲基咪唑四氟硼酸盐(emim]BF4)三组分物系的等压汽液平衡数据。实验结果表明,加入emim]BF4,乙酸甲酯-甲醇二组分物系的汽液平衡线发生偏离,离子液体摩尔分数越大,偏离程度越大;emim]BF4表现出盐效应,使乙酸甲酯对甲醇的相对挥发度增加。用NRTL模型对汽液平衡的实验数据进行了关联,得到二组分交互作用参数。采用该模型参数,乙酸甲酯-甲醇-emim]BF4三组分物系乙酸甲酯的汽相摩尔分数的实验值与计算值的绝对平均偏差为0.003,温度平均偏差为0.3K。

Isobaric Vapor-Liquid Equilibrium for Methyl Acetate-Methanol-1-Ethyl-3-Methylimidazolium Tetrafluoroborate System

Isobaric vapor-liquid equilibrium(VLE) data of methyl acetate-methanol-1-ethyl-3-methylimidazolium tetrafluoroborate(emim]BF4) ternary system were measured at 101.3 kPa in a modified Othmer still.The vapor-liquid equilibrium curve of methyl acetate and methanol with the ionic liquid deviated from the curve of methyl acetate and methanol without the ionic liquid.The greater the ionic liquid mole fraction,the greater the deviation from the curve without the liquid.The ionic liquid emim]BF4 exhibited a salting-out effect which enhanced the relative volatility.The NRTL model was used to correlate the experimental data,and the binary parameters were obtained.The parameters can be employed to predict the VLE of methyl acetate-methanol-1-ethyl-3-methylimidazolium tetrafluoroborate.The mean absolute deviations between the calculated and measured mole fractions of methyl acetate in the vapor phase and equilibrium temperature were 0.003 and 0.3 K for this ternary system,respectively.