Mapping Binary Liquid-Vapor or Liquid-Liquid-Vapor Equilibria Regions, including the Different Azeotropic Behaviours, as a Function of the NRTL Binary Parameters

Abstract

As it is very well know, the synthesis and design of separation processes requires the use of models to represent the phase equilibrium data, which involves the previous correlation of experimental data to obtain the values of the corresponding parameters. In previous works, we have studied the capabilities and limitations of the classical GE models used in phase equilibrium data correlations, such as NRTL model, in representing the behaviour of different LV, LL and LLS equilibrium data. In the preset work, the relations between the binary parameters Aij of the NRTL model and the existence of different equilibrium regions (i.e.: LV, LL or LLV), as well as the different possible azeotropic behaviours are analyzed for different component systems. The Gibbs free enthalpy curve and the corresponding y-x and T-x,y diagrams along a matrix of Aij parameters has been studied within a range including the typical values observed in DECHEMA Chemistry Data Series.