Thermodynamic model for acidic ferrous sulphate from solubility data

摘要

Acidic ferrous sulfate solutions are generated in a large scale in the hydro- and pyrometallurgical industries. They are also produced in the steel industry and titanium dioxide production. Acid mine drainage has long been a significant environmental problem in coal and metal mining. The demand of recycling and reuse of materials has increased significantly especially in EU. Dumping a neutralized deposit is not an option any more. Thus, several techniques of recycling and reuse of sulphuric acid and/or metal sulphates from the side streams are needed. When developing alternative solutions, a better understanding of the thermodynamic behavior of FeSO4-H2SO4-H2O system is needed. In this study a thermodynamic model of this system has been developed in order to yield a thermodynamically consistent set of values for the solubility of iron sulphate, activity of the water and mean activity coefficients of both sulphuric acid and ferrous sulphate in a wide temperature and concentration range.