Thermodynamics of alcohol-alcohol mixtures. 1. A continuous linear association model for alcohol-alcohol solutions

An equation for the excess Gibbs energy of alcohol-alcohol solutions has been derived. The model used in the derivation is based on the hypothesis of a continuous linear association of both alcohol molecules. Expressions for the activity coefficients as well as for the heat of mixing are given. All these expressions contain three for the activity coefficients as well as for the heat of mixing are given. All these expressions contain three parameters which must be adjusted from experimental data; two of them have the physical significance of the equilibrium constants for the self-association process, while the third one is an interactionenergy parameter. The ability of the derived excess Gibbs energy equation to represent several sets of data is shown and the model is compared with other models widely used in the literature.