Systems and Methods for Bipolar Membranes

Patent metadata

Field	Value
Publication number	US-2024024823-A1
Application number	US-202318343597-A
Country	US
Kind code	A1
Filing date	Jun 28, 2023
Priority date	Jun 28, 2022
Publication date	Jan 25, 2024
Grant date	—

Abstract

Systems and methods for catalyzed asymmetric bipolar membranes are described. Catalyzed asymmetric bipolar membranes can sustain desired current densities under low operational voltage for prolonged time periods. Catalyzed asymmetric bipolar membranes can be implemented in electrodialysis cells for various applications such as carbon capture.

First claim

What is claimed is:

1 . A bipolar membrane comprising:
an anion exchange layer comprising an anion exchange membrane; a cation exchange layer comprising a cation exchange membrane, wherein the anion exchange layer has a different thickness than the cation exchange layer such that water transport rate at an anion exchange layer-cation exchange layer interface increases; and a catalyst disposed between the anion exchange layer and the cation exchange layer, wherein the catalyst catalyzes a water dissociation reaction; wherein the catalyst comprises a plurality of ionizable sites with a property of proton donating, proton withdrawing, or a combination thereof, such that the plurality of ionizable sites enhances an electric field at the anion exchange layer-cation exchange layer interface.

2 . The bipolar membrane of claim 1 , wherein the catalyst comprises a material selected from the group consisting of: a two-dimensional material, graphene oxide, a metal oxide, a titanium-based multivalent catalyst, a nanomaterial, a polymer, and any combinations thereof.

3 . The bipolar membrane of claim 1 , wherein the catalyst layer further comprises an ionomer.

4 . The bipolar membrane of claim 1 , wherein the plurality of ionizable sites comprises functional groups of different pk a values.

5 . The bipolar membrane of claim 1 , wherein the anion exchange membrane is selected from the group consisting of: SELEMION®, NEOSEPTA®, Fumapem® FAA, Fumasep® FAP, Sustainion® X37, Versogen® PiperION®, Ionomr Aemion®, and any combination thereof; and the cation exchange membrane comprises Nafion®.

6 . The bipolar membrane of claim 1 , wherein a thickness of the bipolar membrane is greater than or equal to 70 microns.

7 . The bipolar membrane of claim 1 , wherein the anion exchange layer has a thickness less than 100 microns and is thinner than the cation exchange layer.

8 . The bipolar membrane of claim 1 , wherein the cation exchange layer has a thickness less than 100 microns and is thinner than the anion exchange layer.

9 . The bipolar membrane of claim 1 , wherein the membrane is configured to be a portion of an electrodialysis cell.

10 . The bipolar membrane of claim 9 , wherein the electrodialysis cell has a configuration selected from the group consisting of: an H cell, a cell stack, a flow cell, and a flow stack.

11 . The bipolar membrane of claim 9 , wherein the electrodialysis cell comprises a cathode and an anode comprising a material selected from the group consisting of: a metal, a metal alloy, nickel, a nickel-based alloy, copper, a copper-based alloy, titanium, a titanium-based alloy, iron, an iron-based alloy, stainless steel, platinum, gold, silver, carbon, carbon cloth, glassy carbon, graphite, and any combinations thereof.

12 . The bipolar membrane of claim 9 , wherein the electrodialysis cell is a portion of a carbon capture system, an electrochemical conversion system, an energy storage system, a water splitting system, or a carbon dioxide reduction system.

13 . The bipolar membrane of claim 12 , wherein the carbon capture system is a direct ocean capture system.

14 . The bipolar membrane of claim 9 , wherein the electrodialysis cell operates at a current density of greater than or equal to 100 mA/cm 2 and at a voltage of less than or equal to 1.5 V for a duration of at least 60 hours.

15 . An electrodialysis cell comprising:
a freestanding bipolar membrane comprising:
an anion exchange layer comprising an anion exchange membrane;
a cation exchange layer comprising a cation exchange membrane, wherein the anion exchange layer has a different thickness than the cation exchange layer such that water transportation rate at an anion exchange layer-cation exchange layer interface increases; and
a catalyst disposed between the anion and cation exchange layers catalyzes a water dissociation reaction; wherein the catalyst comprises a plurality of ionizable sites with a property of proton donating, proton withdrawing, or a combination thereof, such that the plurality of ionizable sites enhances an electric field at the anion exchange layer-cation exchange layer interface;
an anode and a cathode, wherein the freestanding bipolar membrane is disposed between the anode and the cathode.

16 . The cell of claim 15 , wherein the catalyst comprises a material selected from the group consisting of: a two-dimensional material, graphene oxide, a metal oxide, a titanium-based multivalent catalyst, a nanomaterial, a polymer, and any combinations thereof.

17 . The cell of claim 15 , wherein the catalyst layer further comprises an ionomer.

18 . The cell of claim 15 , wherein the plurality of ionizable sites comprises functional groups of different pk a values.

19 . The cell of claim 15 , wherein the anion exchange membrane is selected from the group consisting of: SELEMION®, NEOSEPTA®, Fumapem® FAA, Fumasep® FAP, Sustainion® X37, Versogen® PiperION®, Ionomr Aemion®, and any combination thereof; and the cation exchange membrane comprises Nafion®.

20 . The cell of claim 15 , wherein a thickness of the bipolar membrane is greater than or equal to 70 microns.

21 . The cell of claim 15 , wherein the anion exchange layer has a thickness less than 100 microns and is thinner than the cation exchange layer.

22 . The cell of claim 15 , wherein the cation exchange layer has a thickness less than 100 microns and is thinner than the anion exchange layer.

23 . The cell of claim 15 , wherein the electrodialysis cell has a configuration selected from the group consisting of: an H cell, a cell stack, a flow cell, and a flow stack.

24 . The cell of claim 15 , wherein the cathode and the anode comprise a material selected from the group consisting of: a metal, a metal alloy, nickel, a nickel-based alloy, copper, a copper-based alloy, titanium, a titanium-based alloy, iron, an iron-based alloy, stainless steel, platinum, gold, silver, carbon, carbon cloth, glassy carbon, graphite, and any combinations thereof.

25 . The cell of claim 15 , wherein the electrodialysis cell is configured to be a portion of a carbon capture system, an electrochemical conversion system, an energy storage system, a water splitting system, or a carbon dioxide reduction system.

26 . The cell of claim 25 , wherein the carbon capture system is a direct ocean capture system.

27 . The cell of claim 15 , wherein the electrodialysis cell operates at a current density of greater than or equal to 100 mA/cm 2 and at a voltage of less than or equal to 1.5 V for a duration of at least 60 hours.

28 . A method for direct ocean capture, comprising:
contacting a water source comprising a dissolved carbon with a bipolar membrane comprising:
an anion exchange layer comprising an anion exchange membrane;
a cation exchange layer comprising a cation exchange membrane; wherein the anion exchange layer has a different thickness than the cation exchange layer such that water transport rate at an anion exchange layer-cation exchange layer interface increases; and
a catalyst disposed between the anion exchange layer and the cation exchange layer catalyzes a water dissociation reaction; wherein the catalyst comprises a plurality of ionizable sites with a property of proton donating, proton withdrawing, or a combination thereof, such that the plurality of ionizable sites enhances an electric field

Assignees

• California Inst Of Techn

Inventors

• Lucas Eowyn
• Atwater Harry A
• Xiang Chengxiang

Classifications

• B01D61/445 Primary

  with bipolar membranes; Water splitting · CPC title

• B01D69/02

  characterised by their properties · CPC title

• B01D61/461

  comprising only a single cell, only one anion or cation exchange membrane or one pair of anion and cation membranes · CPC title

• C02F1/4693

  electrodialysis · CPC title

• B01D2325/42

  Ion-exchange membranes · CPC title