Method for extracting lithium from solution containing lithium

Patent metadata

Field	Value
Publication number	US-9994931-B2
Application number	US-201214418132-A
Country	US
Kind code	B2
Filing date	Dec 28, 2012
Priority date	Jul 31, 2012
Publication date	Jun 12, 2018
Grant date	Jun 12, 2018

Abstract

Disclosed is a method of extracting lithium from a solution including lithium. The method of extracting lithium from a solution including lithium includes: separating the solution including lithium into a monovalent ion-containing solution and a solution including ions having more than divalence using a separation membrane having a negative charge on its surface; removing impurities from the monovalent ion-containing solution; and precipitating lithium dissolved in the monovalent ion-containing solution into lithium phosphate by adding a phosphorus-supplying material to the monovalent ion-containing solution.

First claim

The invention claimed is:

1. A method for extraction of lithium from a solution including lithium, comprising:
separating a solution including lithium into a monovalent ion-containing solution and a solution including ions having divalence or more using a separation membrane having a negative charge on its surface;
removing impurities from the monovalent ion-containing solution; and
adding a phosphorus supplying material to the monovalent ion-containing solution where impurities are removed and then precipitating dissolved lithium into lithium phosphate,
wherein the separation membrane comprises a coating having a sulfone group that is coated onto a polyamide substrate, wherein the sulfone group provides the negative charge.

2. The method for extraction of lithium from a solution including lithium of claim 1 , wherein a pore size of the separation membrane having a negative charge on its surface ranges from 0.5 to 1 nm.

3. The method for extraction of lithium from a solution including lithium of claim 1 , wherein a thickness of the separation membrane having a negative charge on its surface ranges from 0.5 to 1.5 μm.

4. The method for extraction of lithium from a solution including lithium of claim 1 , wherein in the process of removing impurities from the monovalent ion-containing solution, the impurities are non-separated ions having divalence or more.

5. The method for extraction of lithium from a solution including lithium of claim 1 , wherein in a process of removing impurities from the monovalent ion-containing solution,
the impurities comprise magnesium, boron, or calcium.

6. The method for extraction of lithium from a solution including lithium of claim 1 , wherein the solution including lithium is brine.

7. The method for extraction of lithium from a solution including lithium of claim 1 , wherein the method further comprises evaporating the monovalent ion-containing solution from which impurities are removed and then extracting sodium chloride after the process of removing impurities from the monovalent ion-containing solution.

8. The method for extraction of lithium from a solution including lithium of claim 1 , wherein the method further comprises evaporating the monovalent ion-containing solution from which impurities are removed after the process of removing impurities from the monovalent ion-containing solution.

9. The method for extraction of lithium from a solution including lithium of claim 5 , wherein the process of removing impurities from the monovalent ion-containing solution is a process of adding hydroxide anions to the monovalent ion-containing solution and precipitating and removing impurities including magnesium, boron, or calcium included in the monovalent ion-containing solution.

10. The method for extraction of lithium from a solution including lithium of claim 9 , wherein the process of removing impurities from the monovalent ion-containing solution comprises
adding hydroxide anions to the monovalent ion-containing solution and then producing magnesium hydroxide from the magnesium, and
maintaining pH of a filtered solution obtained after removing the magnesium to be greater than or equal to 12 and then precipitating calcium.

11. The method for extraction of lithium from a solution including lithium of claim 10 , wherein the process of removing impurities in the monovalent ion-containing solution comprises:
adding hydroxide anions to the monovalent ion-containing solution and then producing magnesium hydroxide from the magnesium while maintaining pH of the monovalent ion-containing solution to be 8.5 to 10.5;
adsorbing boron on the magnesium hydroxide, co-precipitating the magnesium and boron, and recovering the co-precipitated magnesium and boron; and
maintaining pH of a filtered solution obtained after removing the magnesium and boron to be greater than or equal to 12 and then precipitating calcium.

12. The method for extraction of lithium from a solution including lithium of claim 5 , wherein the process of removing impurities from the monovalent ion-containing solution comprises
a process of reacting calcium in the monovalent ion-containing solution with a carbonation gas and removing it in a form of a calcium carbonate salt.

13. The method for extraction of lithium from a solution including lithium of claim 12 , wherein the process of reacting calcium in the monovalent ion-containing solution with a carbonation gas and removing it in a form of a calcium carbonate salt is performed at pH 5 to 8.5.

14. The method for extraction of lithium from a solution including lithium of claim 12 , wherein the method further comprises reacting magnesium in the monovalent ion-containing solution with a carbonation gas to remove it in a form of a magnesium carbonate salt after the process of reacting calcium in the monovalent ion-containing solution with a carbonation gas and removing it in a form of a calcium carbonate salt.

15. The method for extraction of lithium from a solution including lithium of claim 14 , wherein the process of reacting magnesium in the monovalent ion-containing solution with a carbonation gas to remove it in a form of a magnesium carbonate salt is performed at pH 5 to 12.

16. The method for extraction of lithium from a solution including lithium of claim 14 , wherein reacting calcium in the monovalent ion-containing solution with a carbonation gas to separate it in a form of a calcium carbonate salt, or reacting magnesium in the monovalent ion-containing solution with a carbonation gas to remove it in a form of a magnesium carbonate salt, comprises
a process of spraying brine into the carbonation reaction tank through a droplet spray unit of a carbonation reaction tank charged with a carbonation gas at a predetermined pressure, in a form of droplets.

17. The method for extraction of lithium from a solution including lithium of claim 16 , wherein the carbonation reaction tank is further equipped with an alkali solution supplying unit to control pH.

Assignees

• Posco
• Res Inst Ind Science & Tech

Inventors

• Chon Uong
• Han Gi-Chun
• Kim Ki Young
• Jung So Ra
• Jeung Kee Uek
• Song Chang Ho
• Jang Young Seok

Classifications

• C22B26/12 Primary

  Obtaining lithium · CPC title

• Y02P10/234

  Cross-Sectional Technologies · mapped topic

• C22B3/42

  by ion-exchange extraction · CPC title

• C22B7/006

  Wet processes · CPC title

• C22B3/04

  by leaching (C22B3/18 takes precedence) · CPC title