Method for recovering lithium from lithium ion battery scrap

Patent metadata

Field	Value
Publication number	US-11702719-B2
Application number	US-201816499173-A
Country	US
Kind code	B2
Filing date	Mar 28, 2018
Priority date	Mar 31, 2017
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

A method for recovering lithium from lithium ion battery scrap according to this invention comprises subjecting lithium ion battery scrap to a calcination step, a crushing step, and a sieving step sequentially carried out, wherein the method comprises, between the calcination step and the crushing step, between the crushing step and the sieving step, or after the sieving step, a lithium dissolution step of bringing the lithium ion battery scrap into contact with water and dissolving lithium contained in the lithium ion battery scrap in the water to obtain a lithium-dissolved solution; a lithium concentration step of solvent-extracting lithium ions contained in the lithium-dissolved solution and stripping them to concentrate the lithium ions to obtain a lithium concentrate; and a carbonation step of carbonating the lithium ions in the lithium concentrate to obtain lithium carbonate.

First claim

What is claimed is:

1. A method for recovering lithium from lithium ion battery scrap which has been subjected to a calcination step performed in a temperature range of from 550° C. to 650° C., the method comprising:
a lithium dissolution step of bringing the lithium ion battery scrap into contact with water and dissolving lithium contained in the lithium ion battery scrap in the water to obtain a lithium-dissolved solution;
a lithium concentration step of solvent-extracting lithium ions contained in the lithium-dissolved solution and stripping said lithium ions to concentrate the lithium ions to obtain a lithium concentrate; and
a carbonation step of carbonating the lithium ions in the lithium concentrate to obtain lithium carbonate,
wherein a pH of the lithium-dissolved solution is from 7 to 10.

2. The method according to claim 1 , wherein in the lithium concentration step, said solvent-extracting and the stripping are repeatedly, carried out a plurality of times.

3. The method according to claim 1 , wherein for the solvent-extracting in the lithium concentration step, a solvent extracting agent comprising 2-ethylhexyl 2-ethylhexylphosphonate or di-2-ethylhexylphosphoric acid is used.

4. The method according to claim 1 , wherein a pH during the solvent-extracting in the lithium concentration step is from 5.0 to 6.5.

5. The method according to claim 1 ,
wherein the lithium concentrate obtained in the lithium concentration step contains nickel ions,
wherein the method further comprises a neutralization step of neutralizing the lithium concentrate to recover nickel before the carbonation step.

6. The method according to claim 1 , wherein in the carbonation step, the carbonizing of lithium ions is carried out by adding a carbonate to or blowing a carbon dioxide gas into the lithium concentrate, and a temperature of the concentrate in the carbonating is 50° C. or higher.

7. The method according to claim 1 , further comprising subjecting the lithium ion battery scrap to a calcination step, to a crushing step, and a sieving step.

8. The method according to claim 6 ,
wherein the crushing step and the sieving step are performed in this order, and
wherein the lithium dissolution step is performed before the crushing step, between the crushing step and the sieving step, or after the sieving step.

9. The method according to claim 8 , wherein the lithium dissolution step is carried out after the sieving step.

10. The method according to claim 1 , wherein the lithium ion battery scrap which has been subjected to a calcination step contains lithium oxide or lithium carbonate.

11. The method according to claim 1 , wherein in the lithium dissolution step, an acid is added to the water so that the pH of the lithium-dissolved solution is from 7 to 10.

12. The method according to claim 1 , wherein in the lithium dissolution step, a leaching rate of lithium in water is from 30% to 70%.

13. The method according to claim 1 , wherein in the lithium dissolution step, a leaching rate of lithium in water is from 45% to 55%.

14. The method according to claim 1 , wherein a lithium concentration of the lithium-dissolved solution is from 1.0 g/L to 3.0 g/L.

15. The method according to claim 1 , wherein a lithium concentration of the lithium-dissolved solution is from 1.5 g/L to 2.5 g/L.

16. The method according to claim 1 , wherein an aluminum concentration of the lithium-dissolved solution is from 0 mg/L to 500 mg/L.

Assignees

• Jx Nippon Mining & Metals Corp

Inventors

• Arakawa Junichi
• Haga Yasufumi
• Ito Junichi

Classifications

• B09B3/30

  involving mechanical treatment (involving an extraction step B09B3/80) · CPC title

• B09B3/35

  Shredding, crushing or cutting · CPC title

• C22B26/12 Primary

  Obtaining lithium · CPC title

• B02C23/20

  after crushing or disintegrating · CPC title

• B09B3/80

  involving an extraction step · CPC title