MODIFICATION OF THE PITZER MODEL TO CALCULATE ACTIVITY COEFFICIENTS OF SALTS IN WATER-ETHANOL MIXED SOLVENT SOLUTIONS

1Department of Industrial Chemistry. University of Biskra, Algeria.

2Department of Industrial Chemistry. University of Constantine, Algeria

The approach tested in this work consists in adapting the Pitzer model, initially designed

for aqueous electrolytes solutions, to the case of solutions with a mixed solvent. This

modified model was applied successfully to correlate the activity coefficients of the

electrolytes: NaCl, and NaBr in ethanol-water mixed solvent solutions at 25°C. The

experimental data for these systems are from literature. The results are very encouraging,

the new model can correlate the experimental data for the systems studied with good

precision.