Abstract: The density functional theory and statistical associating fluid theory are used to establish equation of state for binary liquid-liquid system.The parameters of segments are correlated by simultaneously fitting the saturated vapor pressure and the liquid density data.The interfacial region is divided into many extremely thin layers.In equilibrium,the chemical potentials of component i in every layer of the interface are equal to each other and lead to a constant by optimizing the interfacial thickness.The density profiles are calculated from the established EOS.The interfacial tensions of 16 binary water-organic systems are predicted satisfactorily.

摘要： 应用密度泛函理论和统计缔合流体理论建立了二元液液界面的状态方程 ,通过纯流体汽液平衡时的压力数据和液相密度数据回归了非极性流体和极性流体的链节参数 .将界面分层 ,使用已建立的状态方程和回归的纯流体链节参数 ,根据界面各微层达到相平衡时化学势相等的原则计算了液液界面层的厚度和液液界面中的密度分布 ,预测了 16个水 -有机溶剂二元体系的液液界面张力 .计算结果与实验值符合情况良好 .