P Forooghy - Department of chemical engineering, Islamic Azad University, Mahshahr Branch, Mahshahr, Iran
M Alizadeh - Department of chemical engineering, Islamic Azad University, Mahshahr Branch, Mahshahr, Iran
A Pouranfar - Department of chemical engineering, Islamic Azad University, Mahshahr Branch, Mahshahr, Iran

To model the activity coefficients of aqueous solutions of 3-1 electrolytes, we took again the original theory of Pitzer concerning the excess Gibbs energy for the aqueous solutions of electrolytes. The model was applied for 11 systems including 3-1 electrolytes. The performance of this model was compared with other models existing in the literature. The results show that the model of Pitzer can represent the mean ionic activity coefficients of 3-1 electrolytes in aqueous solutions with a standard deviation comparable with the other models and in the majority of the cases better than the others.

Model, Pitzer, Activity Coefficient, electrolytes