Modeling of Solid-Liquid Equilibrium in Nitrobenzene and Para-Xylene Mixtures

Solid-liquid mixtures are very important for the study of molecular interactions that describe the thermodynamic properties of the components. The objective of this work was to determine the behavior of the nitrobenzene and para-xylene mixtures by means of two excess energy models, Margules and Non-Randon Two-Liquid (NRTL), comparing the calculated results with experimental data from the literature. The Margules model, whose parameters varied with temperature, was more accurate than the model that did not consider the temperature variation. The NRTL model was also accurate, presenting only a small deviation in the lower para-xylene compositions, while the ideal case and Margues model with temperature independence presented a large imprecision. Therefore, the two-parameter Margules model with temperature dependence presented the best approximation of the equilibrium system.