Simultaneous description of vapor-liquid equilibrium and excess enthalpies for methanol and ethanol binary mixtures with propanal

Four different formulations of the thermodynamic properties of alcohol + unassociated active component mixtures have been used to describe simultaneously the vapor-liquid equilibrium and excess enthalpies of the methanol + propanal and ethanol + propanal mixtures. The equations used are based on a continuous linear association model proposed by Kretschmer and Wiebe and extended by Nagata and coworkers to include alcohol + unassociated active component mixtures. The equations are severely tested in this attempt to describe the highly non-ideal mixtures formed by an alcohol and propanal. Results obtained are more accurate than those previously reported for the Lattice-Fluid and the Lattice-Fluid Associated Solution models.