Method of oxidative leaching of molybdenum—rhenium sulfide ores and/or concentrates

1. A method for leaching molybdenum and/or rhenium from a sulfide ore and/or concentrate containing such, the method comprising the steps of:

exposing the ore and/or concentrate to an aqueous solution of chlorine-based oxidizing species, the aqueous solution having a pH and comprising hypochlorite and hypochlorous acid, wherein the sum of the concentration of the hypochlorite and hypochlorous acid in the aqueous solution is at least 10 mol % of the chlorine-based oxidizing species;

allowing and/or facilitating oxidation of the molybdenum and/or rhenium by the hypochlorite and/or hypochlorous acid, thereby decreasing the pH such that the predominant chlorine-based oxidizing species becomes chlorine;

allowing and/or facilitating the oxidation of the molybdenum and/or rhenium by the chlorine thereby producing a pregnant leach solution; and

passing the pregnant leach solution to a means for metal recovery.

2. The method according to claim 1 , wherein the step of exposing the ore and/or concentrate to an aqueous solution of chlorine-based oxidizing species in which the chlorine-based oxidizing species is hypochlorite or hypochlorous acid more specifically comprises:

exposing the ore and/or concentrate to an aqueous solution of chlorine-based oxidizing species in which at least 10 mol % of the chlorine-based oxidizing species is hypochlorite.

3. The method according to claim 2 , wherein at least 50 mol % of the chlorine-based oxidizing species is hypochlorite.

4. The method according to claim 3 , wherein hypochlorite ion comprises 99 mol % of the chlorine-based oxidizing species, on a molar basis.

5. The method according to claim 1 , wherein the steps of:

exposing the ore and/or concentrate to an aqueous solution of chlorine-based oxidizing species in which the chlorine-based oxidizing species is hypochlorite or hypochlorous acid;

allowing and/or facilitating the oxidation of the molybdenum and/or rhenium by the hypochlorite and/or hypochlorous acid, thereby decreasing the pH such that the predominant chlorine-based oxidizing species becomes chlorine; and

allowing and/or facilitating the oxidation of the molybdenum and/or rhenium by the chlorine thereby producing a pregnant leach solution;

are performed at ambient temperature.

6. The method according to claim 1 , wherein the steps of:

exposing the ore and/or concentrate to an aqueous solution of chlorine-based oxidizing species in which the chlorine-based oxidizing species is hypochlorite or hypochlorous acid;

allowing and/or facilitating the oxidation of the molybdenum and/or rhenium by the hypochlorite and/or hypochlorous acid, thereby decreasing the pH such that the predominant chlorine-based oxidizing species becomes chlorine; and

allowing and/or facilitating the oxidation of the molybdenum and/or rhenium by the chlorine thereby producing a pregnant leach solution;

are performed at atmospheric pressure.

7. The method according to claim 1 , wherein the ore and/or concentrate exposed to the aqueous solution of chlorine-based oxidizing species in which the sum of the concentrations of hypochlorite and hypochlorous acid is at least 10 mol % of the chlorine-based oxidizing species is previously unleached.

8. The method according to claim 1 wherein the ore and/or concentrate exposed to the aqueous solution of chlorine-based oxidizing species in which the sum of the concentrations of hypochlorite and hypochlorous acid is at least 10 mol % of the chlorine-based oxidizing species is previously unoxidized.