Thermodynamics of the ZnSO4-H2SO4-H2O system

Internally consistent set of thermodynamic parameters was derived for the binary ZnSO4-H2O -system using the CALPHAD method. Available data on water activity, EMF measurements, solubility and heat of solution and dilution measurements was reviewed. Additional parameters for the ternary ZnSO4-H2SO4-H2O system were derived based on the available solubility and boiling point data. Solubility of zinc sulfate was predicted successfully under conditions relevant in hydrometallurgical processing of zinc, and even up to 15 mol kg−1 sulfuric acid solutions. Temperature dependent Pitzer parameters for the binary and ternary systems are reported.