Abstract

The importance of aqueous two-phase systems has been increased recently as a method with greater performance capability in separation and purification of biological products along with economic and operational advantages compared to the conventional methods. However, the thermodynamic modeling of some of applicable aqueous two-phase systems like tetrahydrofuran + polyols has not yet developed. In this study, liquid-liquid equilibrium data for tetrahydrofuran + sorbitol + water ternary system were obtained at 298.15 K. Validity of tie-line data were evaluated by Othmer–Tobias and Bancroft equations while correlative capability of data were investigated by the UNIQUAC and NRTL models. The results of RMSD (1.17% for NRTL (α = 0.5) and 2.12% for UNIQUAC models) clearly show that the NRTL model correlates with the experimental data more satisfactory rather than the UNIQUAC model. Additionally, the effect of pH was investigated on two-phase region and binodal curve changes. The results indicate that there is no significant change in the situation and shape of the binodal curve.

中文翻译：

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四氢呋喃和山梨糖醇形成的水性两相体系的相图、平衡数据和相关性

摘要

作为一种在生物产品分离和纯化方面具有更高性能以及与传统方法相比的经济和操作优势的方法，含水两相系统的重要性最近有所增加。然而，一些适用的水性两相系统（如四氢呋喃 + 多元醇）的热力学模型尚未开发。在本研究中，四氢呋喃 + 山梨糖醇 + 水三元体系的液-液平衡数据在 298.15 K 下获得。连接线数据的有效性通过 Othmer-Tobias 和 Bancroft 方程进行评估，而数据的相关能力通过 UNIQUAC 和 NRTL 进行研究楷模。RMSD 的结果（NRTL 为 1.17%（α = 0.5）和 2。12%（UNIQUAC 模型）清楚地表明 NRTL 模型与实验数据的相关性比 UNIQUAC 模型更令人满意。此外，还研究了 pH 值对两相区域和双节点曲线变化的影响。结果表明，双节点曲线的情况和形状没有显着变化。