Three pyridinium-based ionic liquids (ILs) were adopted to extract isopropanol (IPA) from its aqueous mixture for investigating the potential of these ILs in the separation of a (water + IPA) azeotropic mixture. The liquid–liquid equilibrium values for the mixtures (water + IPA + ILs) was determined at 298.15 K. The selectivity and distribution coefficient were computed, which indicates that the IL n-hexylpyridinium bis(trifluoromethyl sulfonyl)imide displays a better extraction effect to separate the mixture of IPA and water. Besides, the NRTL model was applied to regress the determined tie-line values, and the coherence of the optimized binary parameters was examined using the Gibbs energy surfaces analysis.

中文翻译：

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吡啶系离子液体混合物（异丙醇+水）的液-液相平衡的探索

采用三种基于吡啶鎓的离子液体（IL）从其水性混合物中提取异丙醇（IPA），以研究这些IL在分离（水+ IPA）共沸混合物中的潜力。确定了混合物（水+ IPA + ILs）的液-液平衡值是298.15K。计算了选择性和分配系数，这表明IL n-己基吡啶双（三氟甲基磺酰基）酰亚胺具有较好的萃取效果。分离IPA和水的混合物。此外，应用NRTL模型对确定的联系线值进行回归，并使用吉布斯（Gibbs）能量表面分析检查了优化的二元参数的相干性。