Seawater electrolysis enables mg(oh)2 production and co2 mineralization

Patent metadata

Field	Value
Publication number	US-2025313966-A1
Application number	US-202519242692-A
Country	US
Kind code	A1
Filing date	Jun 18, 2025
Priority date	Oct 18, 2021
Publication date	Oct 9, 2025
Grant date	—

Abstract

A method for producing one or more hydroxide solids includes providing a catholyte comprising an electrolyte solution; contacting the catholyte with an electroactive mesh cathode to electrolytically generate hydroxide ions, thereby precipitating the one or more hydroxide solid(s); and removing the one or more hydroxide solids from the surface of the mesh where they may deposit.

First claim

1 . A method for producing one or more hydroxide solids, the method comprising:
providing a catholyte comprising an electrolyte solution; and contacting the catholyte with an electroactive mesh cathode to electrolytically generate hydroxide ions, thereby precipitating the one or more hydroxide solids.

2 . The method of claim 1 , wherein in the electrolyte solution comprises divalent metal cations.

3 . The method of claim 2 , wherein the divalent cations comprise Mg 2+ , Ca 2+ , or both Mg 2+ and Ca 2+ ions.

4 . The method of claim 3 , wherein the divalent cations comprise Mg 2+ ions.

5 . The method of claim 1 , wherein the electrolyte solution comprises a brine or sea water.

6 . The method of claim 5 , wherein the electrolyte solution comprises sea water.

7 . The method of claim 5 , wherein the concentration of NaCl in the brine or sea water is about 1,000 ppm or more, about 2,000 ppm or more, about 3,000 ppm or more, about 4,000 ppm or more, about 5,000 ppm or more, about 6,000 ppm or more, about 7,000 ppm or more, about 8,000 ppm or more, about 9,000 ppm or more, about 10,000 ppm or more, about 15,000 ppm or more, about 20,000 ppm or more, about 25,000 ppm or more, or about 30,000 ppm or more, about 35,000 ppm or more, about 40,000 ppm or more, about 45,000 ppm or more, about 50,000 ppm or more, about 55,000 ppm or more, or about 60,000 ppm or more.

8 . The method of claim 1 , wherein the electrolyte solution has a Ca-equivalent or Mg-equivalent concentration of about 2 ppm or more, about 10 ppm or more, about 50 ppm or more, about 100 ppm or more, about 200 ppm or more, about 300 ppm or more, about 400 ppm or more, about 500 ppm or more, about 600 ppm or more, about 700 ppm or more, about 800 ppm or more, about 900 ppm or more, about 1000 ppm or more, about 11 ppm or more, about 1200 ppm or more, about 1300 ppm or more, about 1400 ppm or more, or about 1500 ppm or more.

9 . The method of claim 8 , where in the electrolyte solution has an Mg-equivalent concentration of about 1000 ppm or more.

10 . The method of claim 1 , wherein the one or more hydroxide solids comprises Mg(OH) 2 , Ca(OH) 2 , or both Mg(OH) 2 and Ca(OH) 2 .

11 . The method of claim 1 , wherein the one or more hydroxide solids comprises Mg(OH) 2 .

12 . The method of claim 1 , wherein the electroactive mesh cathode comprises a rotating disc cathode having the electroactive mesh disposed thereon.

13 . The method of claim 1 , further comprising removing the one or more hydroxide solids from the surface of the mesh.

14 . The method of claim 13 , wherein the removing the one or more hydroxide solids from the surface of the mesh comprises scraping the surface of the mesh.

15 . The method of claim 13 , wherein removing the one or more hydroxide solids from the surface of the mesh comprises rotating the rotating disc cathode past a scraper.

16 . The method of claim 1 , wherein the electroactive mesh comprises a mesh cathode that comprises a metallic composition, non-metallic composition, or hybrid metallic and non-metallic composition.

17 . The method of claim 16 , wherein the mesh cathode comprises stainless steel, titanium oxide, carbon nanotubes, one or more polymers, graphite, or combinations thereof.

18 . The method of claim 17 , wherein the mesh cathode comprises stainless steel.

19 . The method of claim 1 , wherein the electroactive mesh comprises pores having a diameter in the range of about 0.1 μm to about 10000 μm.

20 . The method of claim 1 , further comprising forming alkalized effluents having a pH greater than 9.

21 . The method of claim 20 , further comprising forming alkalized effluents having a pH greater than 10.

22 . The method of claim 1 , wherein the anolyte comprises an acid.

23 . The method of claim 22 , wherein the anolyte has a pH of less than about 6.

24 . The method of claim 1 , further comprising providing a barrier to separate the catholyte and the anolyte.

25 . The method of claim 24 , wherein the barrier comprises a polymer.

26 . The method of claim 25 , wherein the barrier comprises cellulose, polyvinyl chloride, organic rubber, polyolefin, polyethylene, polypropylene, or any combination thereof.

27 . The method of claim 1 , further comprising cycling the anolyte to a neutralization pool.

28 . The method of claim 27 , wherein the neutralization pool comprises mafic materials, ultramafic materials, calcium-rich fly ash, slag, or any combination thereof.

29 . The method of claim 1 , wherein electrolytically generating hydroxide ions is conducted at a current density of greater than 50 μA/cm 2 .

Assignees

• Univ California

Inventors

• Chen Xin
• La Plante Erika Callagon
• Sant Gaurav
• Jassby David
• Simonetti Dante Adam
• Traynor Thomas

Classifications

• C25B11/046

  Alloys · CPC title

• C25B13/08

  based on organic materials · CPC title

• C25B9/19

  with diaphragms · CPC title

• C25B15/081

  Supplying products to non-electrochemical reactors that are combined with the electrochemical cell, e.g. Sabatier reactor · CPC title

• C25B11/03 Primary

  perforated or foraminous · CPC title