Thermodynamic Modeling of Osmotic Coefficients and Surface Tension of the Ferric Chloride–Water and Ferric Nitrate–Water Systems Using the Pitzer Model

A comprehensive thermodynamic model for aqueous solutions of ferric nitrate and ferric chloride was presented. The temperature dependency of the Pitzer parameters was determined based on the available literature data. New surface tension measurements were carried out in this work for the aqueous solution of ferric nitrate and ferric chloride at 293 K. The model was able to reproduce accurately the thermodynamic properties such as the osmotic coefficient and the activity coefficient. The model was extended to predict the surface tension of these electrolytes with good agreement to the measured values of surface tension.