基于Gibbs－Duhem方程含盐汽液平衡关联式

Correlation Equation for Salt Effect in Vapor Liquid Equilibrium Based on Gibbs Duhem Equation

提出以水－非电解质－电解质三元系Ｇｉｂｂｓ－Ｄｕｈｅｍ方程为基础的含盐汽液平衡关联式。其中电解质在混合溶剂中的活度系数在Ｐｉｔｚｅｒ模型基础上采用微扰法得到，仅有一个微扰系数作为可调参数由试验拟合。在无盐汽液平衡基础上利用该关联式可由盐的浓度计算盐对汽液平衡的影响。与常用的虚拟二元模型相比，本文方法具有理论严格。

A ternary Gibbs Duhem equation was developed to correlate the concentration of electrolyte with VLE data of water nonelectrolyte electrolyte system In the equation the activity coefficient of electrolyte in mixed solvent was calculated by perturbation method based on Pitzers model Only one adjustable parameter needed to be determined with experimental points Thus salt effect in VLE can be calculated within a wider region of liquid concentration under isobaric or isothermal conditions from the concentration of electrolyte Both calculated vapor composition and temperature(isobaric VLE)or pressure(isothermal VLE)were in good agreement with experimental data This method was rigorous in theory and convenient in application as compared with pesudo binary model