Determination of the domain of the function F(HE,GE) = 0 for Wilson, NRTL, LEMF, and UNIQUAC equations

Abstract

The domain boundary for the simultaneous correlation of the excess molar Gibbs free energy (G E ) and the excess molar enthalpy (H E ) of a binary system has been theoretically determined for the Wilson, NRTL, LEMF, and UNIQUAC equations. On this basis, the conditions in which such equations can describe systems with positive and/or negative values of the excess molar entropy (S E ) have been evaluated. The results obtained demonstrate that the knowledge of the domain of the function F(H E ,G E )=0 avoids the inappropriate use of a given correlation equation beyond the corresponding limits