Metal leaching process and apparatus

Patent metadata

Field	Value
Publication number	US-2025115975-A1
Application number	US-202218695478-A
Country	US
Kind code	A1
Filing date	Sep 30, 2022
Priority date	Sep 30, 2021
Publication date	Apr 10, 2025
Grant date	—

Abstract

The invention relates to a process for leaching metals from metal sulfide ore and/or concentrate, comprising: electrolytically generating a leach solution of oxidative halogen-based lixiviant; contacting the metal sulfide ore and/or concentrate with the leach solution of oxidative halogen-based lixiviant to produce a metal-bearing solution; and passing the metal-bearing solution to metal separation.

First claim

1 . A process for leaching metals from metal sulfide ore and/or concentrate, comprising:
electrolytically generating a leach solution of oxidative halogen-based lixiviant; contacting the metal sulfide ore and/or concentrate with the leach solution of oxidative halogen-based lixiviant to produce a metal-bearing solution; and passing the metal-bearing solution to metal separation.

2 . The process according to claim 1 , wherein
electrolytically generating the leach solution comprises electrolytically oxidizing halide in an aqueous precursor solution to produce the oxidative halogen-based lixiviant in situ in the leach solution or in an aqueous feed to the leach solution.

3 . (canceled)

4 . The process according to claim 2 , further comprising separating metal from the metal-bearing solution in metal separation to produce a metal-depleted solution comprising halide, and regenerating the oxidative halogen-based lixiviant following metal separation by recycling at least a portion of the metal-depleted solution to form at least a portion of the aqueous precursor solution.

5 . The process according to claim 4 , wherein the metal-depleted solution comprises soluble iron.

6 . The process according to claim 2 , wherein the aqueous precursor solution comprises sulfate.

7 . The process according to claim 6 , wherein the sulfate is present in the aqueous precursor solution at a concentration of at least 0.1 mol/L.

8 . (canceled)

9 . The process according to claim 1 , wherein the oxidative halogen-based lixiviant comprises hypochlorous acid.

10 . The process according to claim 1 , wherein the leach solution for contacting the metal sulfide ore and/or concentrate comprises the oxidative halogen-based lixiviant at a concentration of less than about 0.05 mol/L.

11 . The process according to claim 1 , wherein the leach solution for contacting the metal sulfide ore and/or concentrate comprises the oxidative halogen-based lixiviant at a concentration of less than about 0.005 mol/L.

12 . (canceled)

13 . The process according to claim 1 , wherein the leach solution for contacting the metal sulfide ore and/or concentrate has a pH of between 3 and 6.5.

14 . The process according to claim 1 , wherein the metal-bearing solution has a pH of at least 2 when passed to metal separation.

15 . (canceled)

16 . The process according to claim 1 , wherein the leach solution for contacting the metal sulfide ore and/or concentrate comprises sulfate.

17 . (canceled)

18 . The process according to claim 1 , wherein the oxidative halogen-based lixiviant is electrolytically generated using a halogen generator, wherein the halogen generator is located proximate to a leach environment comprising the sulfide ore and/or concentrate, and wherein the leach solution is transferred by line from the halogen generator to the leach environment for contact with the sulfide ore and/or concentrate.

19 - 22 . (canceled)

23 . The process according to claim 1 , wherein the metal-bearing solution comprises at least one metal selected from copper, nickel, and cobalt leached from the metal sulfide ore and/or concentrate.

24 . The process according to claim 1 , wherein the metal sulfide ore and/or concentrate comprises a non-metallic oxidizable solid material other than a metal sulfide, and wherein at least a portion of the non-metallic oxidizable solid material is oxidized when contacting the metal sulfide ore and/or concentrate with the leach solution of oxidative halogen-based lixiviant.

25 . (canceled)

26 . The process according to claim 1 , comprising leaching the metal sulfide ore and/or concentrate with a non-oxidative leach solution before and/or after contacting the metal sulfide ore and/or concentrate with the leach solution of oxidative halogen-based lixiviant.

27 . An apparatus for leaching metals from metal sulfide ore and/or concentrate, comprising:
a halogen generator, wherein the halogen generator electrolytically generates a leach solution of oxidative halogen-based lixiviant; a leach environment where the metal sulfide ore and/or concentrate is contacted with the leach solution of oxidative halogen-based lixiviant to produce a metal-bearing solution; and means for metal separation from the metal-bearing solution.

28 . The apparatus according to claim 27 , wherein the halogen generator electrolytically oxidizes halide in an aqueous precursor solution to produce the oxidative halogen-based lixiviant in situ in the leach solution or in an aqueous feed to the leach solution.

29 . The apparatus according to claim 27 , further comprising a line for recycling a metal-depleted solution from metal separation to the halogen generator allowing for regeneration of the oxidative halogen-based lixiviant.

30 - 33 . (canceled)

34 . The apparatus according to claim 27 , wherein the leach environment is a heap for heap leaching.

Assignees

• Commw Scient Ind Res Org

Inventors

• Barnard Keith Raymond
• Shiers Denis William

Classifications

• C22B3/02

  Apparatus therefor · CPC title

• C25B1/26 Primary

  Chlorine; Compounds thereof (by simultaneous production of alkali metal hydroxides and chlorine, oxyacids or salts of chlorine C25B1/34) · CPC title

• C22B23/0423

  Halogenated acids or salts thereof · CPC title

• C22B15/0069

  containing halogen · CPC title

• C25B15/087

  Recycling of electrolyte to electrochemical cell · CPC title