Modeling of thermodynamic properties of
multi-component electrolyte solutions
multi-component electrolyte solutions
(1. College of Chemistry and Chemical Engineering,
Central South University, Changsha 410083, P.R.China;
2. College of Chemistry and Chemical Engineering,
Hunan University, Changsha 410082, P.R.China)
Central South University, Changsha 410083, P.R.China;
2. College of Chemistry and Chemical Engineering,
Hunan University, Changsha 410082, P.R.China)
Abstract: An empiric equation, GH2Oex/(1-x(H2O))2=α+β·x(H2O)/ln(x(H2O)), representing the relation between the excess free energy GH2Oex and mole fraction of water x(H2O) in binary electrolyte solution, was developed and the parameters α and β in the equation were determined by fitting the experimental data for some binary aqueous systems of electrolytes such as CuCl2, NiCl2, HCl, NaCl, KCl, CaCl2 and BaCl2. The activities of water in such ternary and multi-component systems composed of 7 binaries as HCl-H2O-CuCl2, HCl-H2O-NiCl2, HCl-H2O-NaCl, NaCl- H2O-KCl, NaCl- H2O-CaCl2, KCl-H2O-CaCl2, NaCl-H2O-BaCl2, KCl-H2O-CaCl2 and NaCl-H2O-KCl-BaCl2 were predicted by a simplified sub-regular solution model developed by authors from the corresponding binary systems. The predicted results are in good agreement with the measured ones.
Key words: activity； electrolyte； solution； model； interchange energy