Leaching of massive rich copper ore with acidified ferric chloride

Massive rich copper ore, taken from the Küre region of Turkey and containing 7.95% Cu, 2.13% Pb, 0.341% Zn, 0.087% Co, 0.039% Ni, 0.9 (g/t) Au, and 17 (g/t) Ag, was subjected to the experimental study. Effects of leaching time, ferric ion concentration, solid/liquid ratio, acid concentration and temperature on the metal dissolution efficiencies were investigated in order to determine optimum leaching conditions and related leaching kinetics. As a result of these experiments carried out under the optimum leaching conditions, 76% of Cu, 55% of Co, 96% of Ni, 100% of Pb, and 91% of Zn were extracted. The value of apparent activation energy for copper dissolution was found as 43.8 kJ/mole, which is in agreement with the published data. The rate-controlling step was found as the diffusion of ferric ions into the sulfur layer formed on the surface of partially leached ore particles.