Abstract New experimental data on liquid-liquid equilibria (LLE), solubility and critical states in quaternary system propionic acid – 1-propanol – n-propyl propionate – water at 303.15 K and atmospheric pressure are presented. LLE was studied by Gas Chromatography (GC). Solubility and critical (plait) points were investigated by “cloud-point technique” method. Binodal curves and surfaces are presented in concentration tetrahedron. The critical curve is presented in 3d concentration space. A comparative analysis of the results obtained in the work with literature data is carried out. The experimental data are correlated by NRTL model. Standart deviation σ for quaternary mixture does not exceed 0.344%.

中文翻译：

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系统中的液-液平衡、溶解度和临界状态 丙酸 – 1-丙醇 – 丙酸正丙酯 – 水在 303.15 K

摘要 提供了在 303.15 K 和大气压下四元系统丙酸 - 1-丙醇 - 丙酸正丙酯 - 水的液-液平衡 (LLE)、溶解度和临界状态的新实验数据。LLE 通过气相色谱法 (GC) 进行研究。通过“浊点技术”方法研究溶解度和临界（辫）点。双节点曲线和曲面以浓度四面体形式呈现。临界曲线呈现在 3d 浓度空间中。将工作中获得的结果与文献数据进行比较分析。实验数据通过NRTL模型关联。四元混合物的标准偏差 σ 不超过 0.344%。