Method for recovering valuable metal

Patent metadata

Field	Value
Publication number	US-11926883-B2
Application number	US-202118014200-A
Country	US
Kind code	B2
Filing date	Jun 29, 2021
Priority date	Jul 9, 2020
Publication date	Mar 12, 2024
Grant date	Mar 12, 2024

Abstract

Provided is a method which allows for strict control of an oxygen partial pressure required for the heating and melting of a raw material, and thereby more efficient recovery of a valuable metal. The method for recovering a valuable metal (Cu, Ni, and Co) includes the steps of: preparing a charge comprising at least phosphorus (P) and a valuable metal as a raw material; heating and melting the raw material to form a molten body and then converting the molten body into a molten product comprising an alloy and a slag; and separating the slag from the molten product to recover the alloy comprising the valuable metal, wherein the heating and melting of the raw material comprises directly measuring an oxygen partial pressure in the molten body using an oxygen analyzer, and regulating the oxygen partial pressure based on the obtained measurement result.

First claim

The invention claimed is:

1. A method for recovering a valuable metal comprising the steps of:
preparing a charge comprising at least phosphorus (P) and a valuable metal as a raw material;
heating and melting the raw material to form a molten body and then converting the molten body into a molten product comprising an alloy and a slag;
separating the slag from the molten product to recover the alloy comprising the valuable metal,
wherein the heating and melting of the raw material comprises directly measuring an oxygen partial pressure in the molten body using an oxygen analyzer, and regulating the oxygen partial pressure within the range of 10 −14.0 (atm) or higher and 10 −8.0 (atm) or lower based on an obtained measurement result,
the method being devoid of a dephosphorization step of removing phosphorus from the alloy after separating the slag from the molten material and recovering the alloy, wherein the alloy recovered comprises phosphorus in a content of 0.50% by mass or less.

2. The method according to claim 1 , wherein the charge further comprises at least one element of tungsten (W) and chromium (Cr).

3. The method according to claim 2 , wherein the oxygen partial pressure is regulated within the range of 10 −14.0 (atm) or higher and 10 −11.0 (atm) or lower.

4. The method according to claim 2 , wherein the heating temperature in the heating and melting of the raw material is 1,300° C. or higher and 1,500° C. or lower.

5. The method according to claim 2 , wherein the valuable metal comprises at least one metal selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co) and a combination thereof, or an alloy comprising at least one metal selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co) and a combination thereof.

6. The method according to claim 2 , the charge comprises a discarded lithium ion battery.

7. The method according to claim 1 , wherein the oxygen partial pressure is regulated within the range of 10 −14.0 (atm) or higher and 10 −11.0 (atm) or lower.

8. The method according to claim 7 , wherein the heating temperature in the heating and melting of the raw material is 1,300° C. or higher and 1,500° C. or lower.

9. The method according to claim 7 , wherein the valuable metal comprises at least one metal selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co) and a combination thereof, or an alloy comprising at least one metal selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co) and a combination thereof.

10. The method according to claim 7 , the charge comprises a discarded lithium ion battery.

11. The method according to claim 1 , wherein the heating temperature in the heating and melting of the raw material is 1,300° C. or higher and 1,500° C. or lower.

12. The method according to claim 11 , wherein the valuable metal comprises at least one metal selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co) and a combination thereof, or an alloy comprising at least one metal selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co) and a combination thereof.

13. The method according to claim 1 , wherein the valuable metal comprises at least one metal selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co) and a combination thereof, or an alloy comprising at least one metal selected from the group consisting of copper (Cu), nickel (Ni), cobalt (Co) and a combination thereof.

14. The method according to claim 1 , the charge comprises a discarded lithium ion battery.

Assignees

• Sumitomo Metal Mining Co

Inventors

• Yamashita Yu
• Nagakura Toshihiko
• HAGIO Tomoya

Classifications

• C22B1/005

  Preliminary treatment of scrap (C22B1/02 - C22B1/26 take precedence) · CPC title

• H01M10/54

  Reclaiming serviceable parts of waste accumulators · CPC title

• C22B5/10

  by solid carbonaceous reducing agents · CPC title

• C22B23/02

  by dry processes · CPC title

• C22B15/0052

  Reduction smelting or converting · CPC title