Abstract: A formula for the calculation of local composition is derived from Guggenheims quasi-chemical equation. A thermodynamic model based on this formula,which is called the Quasi-Chemical Local Composition model (QCLC), is proposed. The group contribution treatment is introduced into this model and the group interaction parameters for alkane, aromatics, ketone, alcohol and water are obtained by fitting the vapour-liquid equilibrium data of binary systems. A comparison of the predictions with experimental results for ternary systems indicates that the model is better than UNIFAC.

摘要： 以Guggenheim似化学关系为基础,采用微扰理论的方法推导得到符合单流体模型的局部组成表达式,得到了非电解质溶液的Wohl型活度系数模型,通过二元体系汽液平衡数据回归得到了烷烃、芳香烃、酮、醇、水等5类物质各基团的作用参数,对三元体系汽液平衡的预测结果表明该模型预测性能优于UNIFAC.