Modeling electrolyte solutions with the extended universal quasichemical (UNIQUAC) model*
Kaj Thomsen
IVC-SEP, Department of Chemical Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark
Abstract: The extended universal quasichemical (UNIQUAC) model is a thermodynamic model for solutions containing electrolytes and nonelectrolytes. The model is a Gibbs excess function consisting of a Debye–Hückel term and a standard UNIQUAC term. The model only requires binary ion-specific interaction parameters. A unique choice of standard states makes the model able to reproduce solid–liquid, vapor–liquid, and liquid–liquid phase equilibria as well as thermal properties of electrolyte solutions using one set of parameters.
Keywords: extended UNIQUAC; electrolyte; salt; thermodynamic model; databank.
*Paper based on a presentation at the 11th International Symposium on Solubility Phenomena (11th ISSP), Aveiro, Portugal, 25-29 July 2004. Other presentations are published in this issue, pp. 513-665.