Extension of the Three-Particle-Interaction Model for Electrolyte Solutions

Abstract

In this article, the three-particle-interaction correlation model was introduced for prediction of thermodynamic properties in electrolyte solutions. We proposed a new formula to estimate the water activity for aqueous electrolyte solutions at 298.15 K; results showed our model could fit the experimental data very well. Variations of density and electric permittivity were included to improve the predictive accuracy for aqueous systems at other temperatures. This model also was extended for different kinds of nonaqueous solutions. The results of standard deviations (usually below 5%) indicated the good performance of our model. Based on Kumar mixing rule, we developed the model to estimate the mean activity coefficient for mixed aqueous systems with a common ion. Results of NH₄NO₃–KNO₃ (aq) and KCl–K₂SO₄ (aq) system indicated the possibility of prediction of thermodynamic properties for multicomponent system directly from the binary information by using our model.

Keywords:

• Acetonitrile
• Activity coefficient
• Aqueous solutions
• Electrolyte solutions
• Ethanol
• Methanol
• Mixed solutions
• Multicomponent
• N-methylformamide
• Osmotic coefficient
• Solvation
• Solvent activity
• Thermodynamics
• Three-particle-interaction
• 2-Propanol

ACKNOWLEDGMENTS

This work was supported by the National Natural Science Foundation of China (No. 50234040) and National Science Fund for Distinguished Young Scholars of China (No. 50425415).