In this work, {1-ethyl-1-methylpyrrolidinium dimethylphosphate, [C₁C₂PYR][DMP], or 1-hydroxyethyl-1-methylpyrrolidinium dimethylphosphate, [C₁C_2OHPYR][DMP] (1) + ethanol (2)} binary systems were studied as an alternative working pair for the absorption heat pump cycle. It is well known that the knowledge of the thermodynamic properties of the working fluid used plays a key role in the coefficients of performance values, and thus in the efficiency of the apparatus. Therefore, in this work thermodynamic and physicochemical characteristics of ethanol solutions of two dimethylphosphate-based ionic liquids are presented. The isothermal VLE was measured by an ebulliometric method within a temperature range from T = (328.15 to 348.15) K with an increment of 10 K and pressures up to 90 kPa. Experimental VLE data have been successfully correlated using the NRTL equation using temperature-dependence parameters. Additionally, experimental VLE data were tested for thermodynamic consistency using the Van Ness test. The liquid density and dynamic viscosity were determined as a function of IL's mole fraction over a wide composition range at temperature from T = (293.15 to 338.15) K with an increment of 5 K at ambient pressure. For the correlation of physicochemical properties, empirical equations were applied. From experimental density data, the excess molar volumes were determined and correlated using the Redlich – Kister type equation. Additionally, thermophysical properties of pure ILs including glass transition temperature, heat capacity at glass transition, temperature and enthalpy of (solid + solid) phase transition as well as temperature and enthalpy of melting were determined using differential scanning calorimetry (DSC) technique. Data presented in this work, compared to the available literature data for ethanolic solutions of other dimethylphosphate-based ILs, allows discussing the impact of the IL's cation structure on the presented physicochemical and thermodynamic properties. In addition, the data presented in this work were compared to data for a water solution of lithium bromide, commercially used in absorption refrigeration technology.

在这项工作中，{1-乙基-1-甲基吡咯烷二甲基磷酸酯，[C ₁ C ₂ PYR][DMP]，或 1-羟乙基-1-甲基吡咯烷二甲基磷酸酯，[C ₁ C _2OH PYR][DMP] (1) + 乙醇(2)} 二元系统作为吸收式热泵循环的替代工作对进行了研究。众所周知，所用工作流体的热力学性质的知识在性能值的系数中起关键作用，因此在设备的效率中起关键作用。因此，在这项工作中，介绍了两种磷酸二甲酯基离子液体的乙醇溶液的热力学和物理化学特性。等温 VLE 是在从T的温度范围内通过沸腾法测量的 = (328.15 至 348.15) K，增量为 10 K，压力高达 90 kPa。实验性 VLE 数据已成功地通过使用温度相关参数的 NRTL 方程关联起来。此外，使用 Van Ness 测试测试了实验 VLE 数据的热力学一致性。液体密度和动态粘度被确定为 IL 摩尔分数的函数，温度范围从T = (293.15 到 338.15) K，在环境压力下增加 5 K。对于物理化学性质的相关性，应用了经验方程。根据实验密度数据，使用 Redlich-Kister 类型方程确定和关联过量摩尔体积。此外，使用差示扫描量热法 (DSC) 技术测定纯离子液体的热物理性质，包括玻璃化转变温度、玻璃化转变热容量、（固+固）相转变的温度和焓以及熔化温度和焓。与其他基于磷酸二甲酯的 IL 的乙醇溶液的可用文献数据相比，这项工作中提供的数据允许讨论 IL 的阳离子结构对所呈现的物理化学和热力学特性的影响。