In present study, the liquid–liquid equilibrium of the quaternary system of polyethylene glycol (PEG) (with molar masses of 1000, 2000, 6000, and 8000 g·mol−1), sodium tartrate salt, Penicillin G and water at 298 K were investigated. The partitioning of Penicillin G between two aqueous phases was also reported. The extended non random two liquid (NRTL) and extended Universal Quasi Chemical (UNIQUAC) models were used to correlate the experimental equilibrium data. The parameters of these activity coefficient models were optimized for the investigated systems. The results show that the polymer molar mass has a dominant effect on the partition coefficient of Penicillin G. Also, results of both thermodynamic models were very satisfactory and satisfactory predicted the equilibrium concentrations of the components in ATPS. Comparison of the absolute average deviation of the two models shows that the extended UNIQUAC model was superior to the extended NRTL model for correlation and interpolation of phase equilibrium data.

中文翻译：

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聚乙二醇、酒石酸钠、水和青霉素 G 的季水两相体系的实验和热力学模拟

在本研究中，聚乙二醇 (PEG)（摩尔质量为 1000、2000、6000 和 8000 g·mol−1）、酒石酸钠、青霉素 G 和水在 298 K 的四元体系的液-液平衡被调查。还报道了青霉素 G 在两个水相之间的分配。扩展的非随机二液体 (NRTL) 和扩展的通用准化学 (UNIQUAC) 模型用于关联实验平衡数据。这些活度系数模型的参数针对所研究的系统进行了优化。结果表明，聚合物摩尔质量对青霉素 G 的分配系数有显着影响。此外，两种热力学模型的结果都非常令人满意，并且令人满意地预测了 ATPS 中各组分的平衡浓度。