Thermodynamic study of the NaCl --- Na2SO4 --- Na2Cr2O7 --- H2O system at the temperature 298.15 K

The Pitzer ion-interaction model has been used for thermodynamic simulation of the ternary NaCl---Na2Cr2O7---H2O and Na2SO4---Na2Cr2O7---H2O, and the quaternary NaCl---Na2---SO4-Na2Cr2O7-H2O systems at T=298.15 K. The necessary thermodynamic functions (binary and ternary parameters of interionic interaction and thermodynamic solubility products) have been calculated and the theoretical solubility isotherms have been plotted. Good agreement between experimentally determined and calculated solubilites has been found.