Some complexed gold ores present high percent of copper content and it inhibits the direct use of classical hydrometallurgical cyanidation process for gold recovery. This paper presents the experimental results of a hydrometallurgical route for gold ore pre-treatment aiming at extracting copper for further cyanidation. Some experiments were carried out using H2SO4, Fe2(SO4)3, H2O2, HCl, HClO4 and NH4OH. The highest percent of copper extracted (50%) was obtained for using sulfuric acid at 82 ± 2ºC during 15 minutes, and using a combination of sulfuric acid and hydrogen peroxide at 25 ± 2ºC during 15 minutes. The experimental results of this work were lower than 95% percent of copper extracted and considered unsuitable for the cyanidation stage and gold recovery.
copper; gold; leaching
