Abstract

The modeling of vapor-liquid equilibrium in binary and ternary systems that include substances found in wine and must distillation processes, is analyzed. In particular, the modeling of binary mixtures containing water+congeners and ethanol+congeners and ternary mixtures containing water and two congeners, have been studied. The congener are low concentration components, but of importance in alcoholic distillation processes, are present in a must in concentrations of part per million, 10-6 a 10-4 mg/L, and their concentration is an important enological parameter. This work analyzes the use of the correlation model NRTL, the prediction model UNIFAC and the predictive model PSRK, that uses a mixing rule which include the Gibbs free energy. It is shown that the NRTL model is the most appropriate to correlate available data for binary systems. For the ternary systems, the three models give similar results for the saturation temperature and the congener concentration in the gas phase. However, the accuracy of these models for cases in which the concentration of the congeners is very low, cannot be clearly defined due to the lack of experimental data in this range of concentration.