WO2003006695B1 - Hydrometallurgy method for leaching oxidised ores and metal recovery - Google Patents

Abstract

The invention concerns a hydrometallurgy method comprising, in a first step, leaching oxidised ore with an aqueous solution inert with respect to the acid or basic gangue, containing amine and/or ammonium carboxylate(s) and/or carbonate(s), selected on the basis of their complexing power with respect to the metals being treated, in particular copper, iron, zinc, cadmium, nickel, cobalt, manganese, silver and/or gold and/or any other transition metal of the periodic table of chemical elements, the metal(s) being brought to the adapted degree of oxidation by air or oxygen injection, and, in a second step, precipitating the metal salts by standard methods, the metal-depleted solution being reusable, after regeneration if required, with the usual equipment in the fields of hydrometallurgy and chemical engineering.

Claims

AMENDED CLAIMS [received by the International Bureau on 1 November 2002 (1 1.1 1.2002); original claims 1-5 replaced replaced by amended claims 1 -5, claim 6 deleted (1 page)] 1. Process for the hydrometallurgy for the recovery of oxidized metal ores, their concentrates or the sulphide roasting ash consisting of the lix viation of the charge by a solution of carboxylates and or amine and ammonium carbonates and the precipitation metals extracted in the form of salts or metals. 2. Process according to claim 1, characterized in that the metal (s) extracted by said solution are the transition metals of the periodic classification of the chemical elements, in particular copper, nickel, zinc, cadmium, chromium, cobalt, silver, gold, manganese, the metal or metals being present in the feed in the form of oxides, carbonates, silicates or salts of other weak acids, the metals being brought eventually at the appropriate oxidation state, in particular by injecting air or oxygen during leaching. 3. Process according to claim 1, characterized in that the carboxylates and / or carbonates and the amines and or ammonium of the leaching solution are selected according to their complexing power vis-à-vis the metals subject of recovery, to exclusion of volatile or thermally unstable compounds such as carbonate, acidic carbonate or ammonium carbamate. 4. Process according to claims 1, 2 and 3, characterized by the possibility of recovering the leached metals in the form of hydroxides, salts or metal by injection into the rich solution of gases such as carbon monoxide, anhydriαe sulfurous, pressure, or hydrogen sulphide, without any noticeable impairment of the leaching ability of the recycled solution, or by other conventional methods of recovery such as carburizing, electrolysis or solvent extraction. 5. Process according to claims 1, 2 and 3, characterized in that the leaching solution, of neutral or slightly acidic or weakly basic pH, is inert with respect to the acidic or basic gangues and with respect to the concrete, aluminum and aluminum. other equipment manufacturing materials.