Abstract: 1-Aminopropyl-3-methy-limidazolium bromide([APMIm][Br])is a functional ionic liquid(IL)for good absorption to carbon dioxide and its aqueous solution can be employed to the process of high efficiency absorption and desorption cycle.It is important to study the property of its aqueous solutions.In this study,reliable experimental data on the vapor-liquid equilibrium of[APMIm][Br]aqueous solution were obtained under the condition of middle-low temperatures.The vapor pressures of the binary system was measured at 278.15-384.15 K and in a range of 10.0%-90.9% ionic liquid(g·g^-1).An activity coefficient model with an idle factor for association of IL moles was applied by taking into account the aggregation effects of IL molecules in aqueous solutions.The model can effectively present the vapor-liquid equilibrium characteristics of IL solution for middle-low temperatures and full range of mole concentration and correlate the experimental data very well with a relative mean deviation of 2.15%.

Key words: ionic liquid, aqueous solution, vapor-liquid equilibrium

摘要： 1-氨丙基-3-甲基咪唑溴盐([APMIm][Br])是一种对CO₂有良好吸收性能的功能型离子液体,在工业中可采用水溶液来实现高效能的吸收和解吸循环过程,因此对其水溶液特性的研究至关重要。对[APMIm][Br]水溶液在中低温度下的汽液相平衡进行了测量,获得可靠的实验数据,从而揭示其水溶液特性。实验温度范围为278.15～348.15 K,[APMIm][Br]在水溶液中质量分数分别为10.0%、20.3%、29.5%、40.0%、57.5%、75.3%、84.0%、88.9%、90.9%。考虑了低温下离子液体分子在水溶液中的强缔合特性,采用带缔合惰化因子的离子液体水溶液活度模型对实验数据进行了拟合,实验值与计算结果符合很好,平均相对误差为2.15%。

关键词: 离子液体, 水溶液, 汽液相平衡