Prediction of excess functions of some multicomponent organic mixtures of hydrocarbons with a group contribution model

Abstract

In order to study the performance of the Kehiaian-Guggenheim-Barker group contribution model on the characterisation of the excess molar functions of multicomponent organic mixtures, we present here the predictions of this model for the concentration dependence of three sets of G E ternary data, eight sets of H E ternary data, and one set of four and another of five-component H E data. The thirteen mixtures are formed for n-alkanes, cyclohexane and aromatic hydrocarbons and have been treated in the zeroth-order approximation of the theory. The ratio of the standard deviations between experimental and predicted excess molar enthalpies H E or excess molar Gibbs functions G E is less than 0.06 for all the systems. Since only the interaction parameters obtained from the binary systems are used and no new parameters are adjusted to perform the prediction, a satisfactory representation was reached in all cases.