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 thermodynamicproperties 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 ammoniumion selective electrode (NH4–ISE) versus a nitrate ion selective electrode (NO3–ISE) as areference 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 hasbeen used for correlating the data and some thermodynamic results were achieved. A comparisonof the results with similar systems of references shown that agreement is excellent. The Gibbsfree energy of transfer from water to mixed solvent for NH4NO3 were evaluated together withthe model parameters.The results of optimization by Pitzer model were meaningful andsupplementing the correlation using the modified ion-interaction model of Pitzer has led toslightly more reasonable results.

Keywords:

Activity Coefficients , Gibss Free Energy of Transfer , Solvation , NH4NO3 and Fructose