Activity Coefficient Determination of the Ternary System: NH4NO3+ Fructose+ H2O by Potentiometric Method

This research focuses on the the modeling of activity coefficients and some thermodynamic properties of the ternary NH4NO3+Fructose+ water at 298.15 °K using the electromotive force (emf) measurements and the cell was without junction. Electrochemical cell with an ammonium ion selective electrode (NH4–ISE) versus a nitrate ion selective electrode (NO3–ISE) as a reference electrode was used to determine the activity coefficients for NH4NO3– monosaccharide (Fructose) systems in water at 298.15 °K. Pitzer and modified Pitzer ion-interaction model has been used for correlating the data and some thermodynamic results were achieved. A comparison of the results with similar systems of references shown that agreement is excellent. The Gibbs free energy of transfer from water to mixed solvent for NH4NO3 were evaluated together with the model parameters.The results of optimization by Pitzer model were meaningful and supplementing the correlation using the modified ion-interaction model of Pitzer has led to slightly more reasonable results.