采用绝热量热法测量了由离子液体1-丁基-3-甲基咪唑磷酸二丁酯([bmim][DBP])分别与CH3OH、C2H5OH和H2O所组成的3个二元工质溶液体系[bmim][DBP](1)+CH3OH(2)/C2H5OH(2)/H2O(2),以及2个三元工质溶液体系[bmim][DBP](1)+CH3OH(2)/C2H5OH(2)+H2O(3)在298.15K和常压下的摩尔混合焓HEm。利用Gibbs-Helmholtz方程和NRTL活度系数模型,对每个二元溶液体系摩尔混合焓的实验数据进行关联,获得模型方程中的组分作用参数。摩尔混合焓的模型拟合值与实验值的平均相对偏差分别为1.81%、1.44%和0.72%。在此基础上预测了2个三元工质溶液体系的摩尔混合焓。结果表明:三元工质溶液体系的摩尔混合焓在实验浓度范围内均为负值,混合为放热过程。表明三元工质溶液具有成为吸收制冷循环新工质溶液的基本特征;采用NRTL模型预测2个三元溶液体系摩尔混合焓的计算值与实验值的平均相对误差分别为2.31%、2.49%。
The excess molar enthalpies of binary and ternary working solutions containing ionic liquid,1-butyl-3-methylimidazolium dibutylphosphate,(1)+ CH3OH(2)/C2H5OH(2)/H2O(2)and(1)+ CH3OH(2)/C2H5OH(2)+ H2O(3)were measured with an adiabatic calorimeter at 298.15 K under the normal atmospheric pressure.The experimental excess molar enthalpies of binary working solutions were correlated with non-random two liquid(NRTL)activity coefficient model,and the binary interaction parameters were obtained.The average relative deviations between the correlated excess molar enthalpies and the experimental values for three binary solutions are 1.81%,1.44% and 0.72%.For the excess molar enthalpies of two ternary solutions predicted based on the binary interaction parameters,the average relative deviations between the predicted and the experimental excess molar enthalpies are 2.31% and 2.49%.The excess molar enthalpies for the binary solutions and the ternary solutions are negative in the whole range of IL concentration,so the mixing processes of with water and methanol or ethanol are exothermic,which is one of the basic property of working solution in absorption cycles.