关键词: 离子液体, 汽液平衡, NRTL方程

Abstract: Ionic liquid as a benign solvent is of great potential to be used in chemical reaction and separation processes, and the modeling of vapor-liquid equilibrium(VLE) for the ionic liquid-containing systems is of both theoretical and practical significance.By using the NRTL equation for non-electrolyte solution, the VLE isotherms for ［bmim］［PF₆］-H₂O and ［C₈mim］［PF₆］-H₂O binary systems were correlated with deviation within 2% and the VLE data at other temperatures were predicted with the mean relative deviation within 5%.The experimental infinite dilution activity coefficients of some organic chemicals in ionic liquids C₈H₁₄S₂O₄F₆N₃ and C₉H₁₆S₂O₄F₆N₃ at different temperatures were correlated successfully with the NRTL equation,and the binary parameters thus obtained were used to study the effect of ionic liquid on the VLE of azeotropic binary systems. It was shown that VLE for ionic liquid-containing systems could be well represented with the conventional NRTL equation.The relative volatility of components could be largely affected and azeotropic point could even be eliminated by the “salt effect” of ionic liquid.

Key words: 离子液体, 汽液平衡, NRTL方程