Apparatus and method for producing li metal

Patent metadata

Field	Value
Publication number	US-2025101622-A1
Application number	US-202318728758-A
Country	US
Kind code	A1
Filing date	Jan 12, 2023
Priority date	Jan 13, 2022
Publication date	Mar 27, 2025
Grant date	—

Abstract

There are provided an apparatus and a method for producing lithium metal by electrolysis of LiCl in a diaphragmless electrolytic cell. The method and apparatus of the invention make use of a liquid-liquid separator which is at least one film coalescer or at least one centrifugal separator to coalesce or separate lithium metal from the Li metal/electrolysis medium mixture produced in the electrolytic cell. There is also provided a method for producing lithium metal from Li2O in an electrolytic cell, the method comprising feeding Li2O or feeding LiCl produced from Li2O to the electrolytic cell.

First claim

What is claimed is:

1 . An apparatus for producing lithium metal by electrolysis, the apparatus comprising:
a liquid-liquid separator and a diaphragmless electrolytic cell equipped with:
an anode and a cathode immersed in an electrolysis medium comprising molten LiCl,
a gaseous chlorine outlet located at the top of the cell, and
a Li metal/electrolysis medium mixture outlet adjacent to a surface level of the electrolysis medium in the cell, wherein said mixture outlet is in fluid connection with the liquid-liquid separator to allow passage of a mixture of the electrolysis medium and lithium metal produced by the electrolytic cell into the liquid-liquid separator,
wherein said liquid-liquid separator comprises at least one film coalescer or at least one centrifugal separator for separating the lithium metal produced by the electrolytic cell from the electrolysis medium.

2 - 7 . (canceled)

8 . The apparatus of claim 1 , wherein the cell further comprises an electrolyte medium inlet towards the base of the cell.

9 . The apparatus of claim 1 , further comprising an electrolysis medium reservoir and a first conduit fluidly connecting the base of the reservoir to the base of the cell.

10 . (canceled)

11 . The apparatus of claim 9 , further comprising a chlorine bubbler in the reservoir.

12 - 13 . (canceled)

14 . The apparatus of claim 1 , further comprising a collection tank for collecting a stream of liquid comprising Li metal produced by the liquid-liquid separator.

15 . The apparatus of claim 14 , wherein the collection tank is located under the liquid-liquid separator.

16 - 17 . (canceled)

18 . The apparatus of claim 1 , wherein the liquid-liquid separator (and the collection tank if present) are enclosed within a separation chamber.

19 . The apparatus of claim 18 , wherein the liquid-liquid separator is located between, and immediately adjacent to, the electrolysis medium reservoir and the electrolytic cell.

20 . The apparatus of claim 1 , further comprising:
a chlorination reactor for the chlorination of Li 2 O into LiCl or a LiCl—Li 2 O mixture, wherein the chlorination reactor is equipped with a chlorine gas inlet, an oxygen gas outlet, a Li 2 O inlet, a LiCl/LiCl—Li 2 O mixture outlet, and a heating element, and a fifth conduit connecting the LiCl/LiCl—Li 2 O mixture outlet of the chlorination reactor either to the LiCl/LiCl precursor inlet of the reservoir or to the electrolyte medium inlet of the cell.

21 . (canceled)

22 . The apparatus of claim 1 , further comprising:
a dehydration reactor for the production of Li 2 O from LiOH, wherein the dehydration reactor is equipped with a water vapor outlet, a LiOH inlet, a Li 2 O outlet, and a heating element and/or a vacuum pump, and a seventh conduit connecting the Li 2 O outlet of the dehydration reactor to the Li 2 O inlet of the chlorination reactor, to the LiCl/LiCl precursor inlet of the reservoir or to the electrolyte medium inlet of the cell.

23 . The apparatus of claim 1 , further comprising:
a decarbonation reactor for the production of Li 2 O from Li 2 CO 3 , wherein the decarbonation reactor is equipped with a CO 2 gas outlet, a Li 2 CO 3 inlet, Li 2 O outlet, and a heating element and/or a vacuum pump, and an eighth conduit connecting the Li 2 O outlet of the decarbonation reactor to the Li 2 O inlet of the chlorination reactor, to the LiCl/LiCl precursor inlet of the reservoir or to the electrolyte medium inlet of the cell.

24 . A method for producing lithium, the method comprising:
a) electrolyzing an electrolysis medium comprising molten LiCl in a diaphragmless electrolytic cell, b) collecting a mixture of lithium metal and electrolysis medium from said cell, and c) coalescing or separating lithium metal from said mixture using a liquid-liquid separator, wherein said liquid-liquid separator comprises at least one film coalescer or at least one centrifugal separator.

25 - 29 . (canceled)

30 . The method of claim 24 , further comprising the step of feeding molten LiCl, a precursor thereof, or a mixture thereof to the cell, and, if a precursor is fed, allowing chlorine gas produced by the cell to chlorinate the precursor thus yielding molten LiCl.

31 - 33 . (canceled)

34 . The method of claim 30 , further comprising the step of producing molten LiCl from a LiCl precursor in the reservoir.

35 - 36 . (canceled)

37 . The method of claim 30 , further comprising the step of producing LiCl or a LiCl—Li 2 O mixture by chlorination of lithium oxide and then adding the LiCl or LiCl—Li 2 O mixture to the reservoir or to the cell.

38 . The method of claim 30 , further comprising the step of producing Li 2 O by dehydration of lithium hydroxide or by decarbonation of lithium carbonate.

39 . The method of claim 24 , further comprising the step of collecting a stream of liquid produced by the liquid-liquid separator, said stream comprising Li metal and the electrolysis medium, and allowing decantation of the stream into a phase of Li metal over a phase of electrolysis medium.

40 . (canceled)

41 . The method of claim 24 , further comprising the step of using heat from the cell to heat the separator.

42 . A method for producing lithium metal from Li 2 O, the method comprising:
1) feeding Li 2 O, LiCl produced from Li 2 O, or a mixture thereof to an electrolytic cell, said electrolytic cell comprising an anode, a cathode and an electrolysis medium comprising molten LiCl; and 2) electrolyzing the molten LiCl in said electrolytic cell to produce Li metal and chlorine gas.

43 . The method of claim 42 , wherein Li 2 O is fed to the cell at step 1) and wherein the chlorine gas produced at step 2) is allowed to react with the Li 2 O to produce LiCl, which is then electrolyzed at step 2) to produce Li metal.

44 . The method of claim 42 , further comprising chlorinating Li 2 O to produce LiCl, and then feeding the LiCl produced from Li 2 O, with or without unreacted Li 2 O, to the cell at step 1).

45 - 50 . (canceled)

Assignees

• Hydro Quebec

Inventors

• Amouzegar Kamyab
• Allard François
• Champagne Pascal
• Bouchard Patrick
• Leblanc Dominic
• Tougas Bernard
• Turcotte Nancy

Classifications

• C25C7/06

  Operating or servicing · CPC title

• B01D17/0217 Primary

  by centrifugal force · CPC title

• Y02P10/20

  Recycling · CPC title

• C25C3/02 Primary

  of alkali or alkaline earth metals · CPC title

• C25C7/005

  of cells for the electrolysis of melts (C25C7/02 - C25C7/06 take precedence) · CPC title