Static properties of solutions: Van der Waals and related models for hydrocarbon mixtures

Abstract

The van der Waals equation of state, in spite of its oversimplifications, gives useful qualitative information about mixtures over a wide range of temperatures and pressures. When the Brönsted principle of congruence is used to evaluate the parameter a 12 for the mixture, a wide range of properties can be predicted: excess functions (including temperature and composition dependence) and phase equilibria (including lower critical solution phenomena at high temperatures), in good qualitative agreement with experimental properties of mixtures of n-alkanes.