Determination of water activity, osmotic coefficients, activity coefficients, solubility and excess Gibbs free energies of NaCl-sucrose-H2O mixture at 298.15 K

Abstract

The relative humidities on ternary NaCl-sucrose-H2O solution of 0.5, 1.0, 2.0, 4.0 and 5.5 mol·kg−1 of sucrose have been determined by the hygrometric method at 298.15 K in the molality range from 0.5 to 6.0 mol·kg−1 of NaCl. The obtained data allow the deduction of the water activities and osmotic coefficients. The experimental results are compared with the predictions of the extended composed additivity (ECA) rule, the Lin et al. equation, and Lietzke and Stoughton (LS II) models. The obtained results were interpreted by using Pitzer-Simonson-Clegg model. The four mixture parameters are determined and used to predict the activity coefficients of NaCl and sucrose in the mixed solution. The solubility, excess Gibbs energy and The Gibbs energies of transfer of sodium chloride are also calculated for this system.