PROCESS FOR THE RECOVERY OF NOBLE METALS FROM ORE- CONCENTRATES

摘要

The invention relates to the hydrometallurgical recovery of gold and silver by direct oxidizing sulphuric acid-digestion of arsenopyrite-concentrates (FeAsS2) containing carbonaceous materials, with a silicate gangue, and/or a silicate and pyrite gangue, whereby arsenic and iron are fully solubilized and the noble metals are quantitatively enriched in the silicate-residue. The concentrate is subjected to mechano-chemical stress to produce structural deformations before being digested in the presence of oxygen. After decarbonization of the residue gold and silver can be recovered by cyanide leaching without losses due to adsorption. The invention also relates to a bulk process for preparing gold and silver rich concentrates.