Iodine Leaching of Gold from Lean Gold Ore with Charcoal

Gold leaching from refractory Au ores using iodine and iodides was investigated. Thermodynamic analysis showed that the process is feasible. The technological parameters of iodine leaching were optimized. Comparing to the cyanidation process, iodine leaching gives better metallurgical performance, shorter leaching time and higher Au recovery. The Au recovery reached 95% after iodine leaching for 4 h, whereas the cyanidation process of 12 h gave a Au recovery of 80%.