Calculation of enthalpy of mixing at infinite dilution by the nrtl and uniquac models

Enthalpies of mixing at infinite dilution have been calculated for 42 binary systems of liquid mixtures using the NRTL and UNIQUAC models. Temperature-dependent parameters of the models are used in the calculations. These parameters have been estimated by regressing excess Gibbs energy, g^E, and enthalpy of mixing, h^E, data simultaneously. The calculated values are compared with experimental infinite dilution enthalpy of mixing obtained by extrapolation of finite concentration h^E data published in the literature. The performance of the models is satisfactory for only slightly non-ideal and polar systems and the choice of the best model is mainly system dependent.