A MODEL FOR PREDICTING THE EXCESS-ENTHALPIES OF TERNARY MIXTURES

A new model, based on statistical thermodynamic principles, has been d eveloped for predicting the excess enthalpy of a ternary mixture from correlations of the enthalpies of its constituent binaries. The model provides a definite expression containing nine parameters. Since these are determined by analyses of the binary data alone, a real predictio n of the ternary enthalpies is obtained. The model has been used to pr edict the excess enthalpies of 12 ternary systems involving a fairly w ide variety of molecular species. The present treatment usually provid es a better prediction of the ternary excess enthalpies than either th e NRTL or the UNIQUAC models.