离子液体1,3-二甲基咪唑磷酸二甲酯盐-甲醇浓溶液气液平衡

为了测定1,3-二甲基咪唑磷酸二甲酯盐([mmim]DMP)-甲醇体系在离子液体含量较高时的气液平衡数据,采用静态法测定了摩尔分数为0.40—0.47的[mmim]DMP-甲醇溶液在30—90℃的饱和蒸气压,并用非随机双液体(NRTL)模型对实验数据进行关联,得到相应的模型参数和关联偏差。结果表明:不同浓度溶液所适用的NRTL模型在参数形式和数值上也略有差异,文中的5个参数NRTL模型适用于中高浓度区,对溶液饱和蒸气压的关联偏差为0.015 9;不同浓度溶液的饱和蒸气压与温度的对应关系均与纯溶剂类似,符合Antoine方程的形式。从气液平衡的角度分析,[mmim]DMP-甲醇体系具有作为吸收式制冷工质对的应用潜质。

Vapor-liquid equilibrium for high concentration solution of 1,3-dimethylimidazolium dimethyl phosphate-methanol

To measure vapor-liquid equilibrium (VLE) data of 1,3-dimethylimidazolium dimethyl phosphate ([mmim]DMP)-methanol binary system at relatively high concentration of the ionic liquids (IL), static method was employed to measure the saturated vapor pressure of the [mmim]DMP-methanol solutions at 30-90 ℃ with the mole fraction of [mmim]DMP ranging from 0.40 to 0.47. The experimental data were correlated by non-random two liquids (NRTL), and the model parameters and the correlation deviation were calculated. The results indicate that the parameters of the NRTL models that can be applied to the different concentrations of solutions are slightly different in both form and value. The selected NRTL model with five parameters is applicable to the medium to high concentration zones, and the correlation deviation is 0.015 9. As the low concentration solutions, the relationships between the saturated vapor pressure of the medium to high concentrations and the temperature are similar to the pure solvent, which obey the Antoine equation. From the viewpoint of the VLE analysis, the [mmim]DMP-methanol binary system can be considered as a promising working pair for the absorption refrigeration system.