A Generalized Kinetic Model for Hydrometallurgical Processes

In electrochemical leaching processes the solid must be an electric conductor, e.g., a metal, or a semiconductor, e.g., certain metal sulfides or oxides. Reaction takes place by the transfer of electrons at the solid surface and involves oxidation-reduction processes that take place simultaneously at two different locations not far from each other. At one location, electrons are picked up by a depolarizer, D, in solution, e.g., O-2, H+, etc. (the cathodic zone) and at another location metal ions are released in solution (the anodic zone) where they react with reagent C.A single kinetic law derived theoretically is obeyed: Rate = k(1)k(2)A[D][C] / (k(1)[D] + k(2)[C]) where k1 and k2 are constants, and A is the total surface area of the dissolving solid.