Abstract:

The gas-liquid phase equilibrium experimental system based on the isochoric saturation method in the laboratory was improved. The visual equilibrium cell, thermostatic system and magnetic stirring system were modified. In order to check the reliability and accuracy of the new system, the phase equilibrium of carbon dioxide and pentaerythritol tetrahexanoate was measured at 303.15 K, the absolute average deviation was 0.95% and the maximum deviation was 2.01% compared with the reference data. The expanded uncertainties of temperature, pressure and mole fraction are 0.03 K, 2.0 kPa, and 3.0%, respectively. Phase equilibria behavior of trans-1,3,3,3-tetrafluoropropene and squalane was determined at temperature range from 283.15 K to 348.15 K. The experimental data were correlated with Peng-Robinson equation of state and van der Waals mixing rule using two interaction parameters. The absolute average deviation between experimental data and calculated values for pressure was 0.88%, and the maximum deviation was 3.80%. In addition, the immiscibility phenomenon for trans-1,3,3,3-tetrafluoropropene and squalane mixtures was found in the temperature range from 283.15 K to 333.15 K.

Key words: phase equilibria, measurement, binary mixture, trans-1,3,3,3-tetrafluoropropene, squalane

摘要：

在原有等体积饱和法相平衡实验台的基础上，改进了可视窗口的平衡釜、调整了控温及搅拌系统。为了验证装置的可靠性，测量了温度为303.15 K时二氧化碳与季戊四醇四己酸酯的相平衡，测量结果与文献值的绝对平均偏差为0.95%，最大偏差为2.01%。在此基础上，采用改进的实验装置，测量了制冷剂1，3，3，3-四氟丙烯与异三十烷在温度为283.15~348.15 K范围内的汽液相平衡性质。利用PR状态方程及双参数的van der Waals混合规则对实验结果进行了关联，计算的平衡压力和实验压力的绝对平均偏差为0.88%，最大偏差为3.80%。此外，在温度范围为283.15~333.15 K内发现了1，3，3，3-四氟丙烯与异三十烷的不互溶现象。

关键词: 相平衡, 测量, 二元混合物, 1,3,3,3-四氟丙烯, 异三十烷