Kinetics and Modeling of Chemical Leaching of Sphalerite Concentrate Using Ferric Iron in a Redox-controlled Reactor

This work presents a study for chemical leaching of sphalerite concentrate under various constant Fe3＋ concentrations and redox potential conditions. The effects of Fe3＋ concentration and redox potential on chemical leaching of sphalerite were investigated. The shrinking core model was applied to analyze the experimental results. It was found that both the Fe3＋ concentration and the redox potential controlled the chemical leaching rate of sphalerite. A new kinetic model was developed, in which the chemical leaching rate of sphalerite was proportional to Fe3＋ concentration and Fe3＋ /Fe2＋ ratio. All the model parameters were evaluated from the experimental data. The model predictions fit well with the experimental observed values.