# US 2024/0198280 A1 · Method and absorbent for absorbing carbon dioxide from air > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0198280 A1 - Document ID: US20240198280A1 - Status: Published application - Kind: A1 - Application number: 18/279,366 - Filed: 2022-03-03 - Published: 2024-06-20 - Earliest claimed: 2021-03-03 - Assignees: Greenlyte Carbon Technologies GmbH - Applicants: Greenlyte Carbon Technologies GmbH - Inventors: Peter Behr - Web page: https://patentgrep.com/patent/US20240198280A1 ## CPC - B01D 53/1475: {Removing carbon dioxide} - B01D 53/1493: {Selection of liquid materials for use as absorbents} - B01D 53/1425: {Regeneration of liquid absorbents} - B01D 53/965: {including an electrochemical process step} - B01D 2252/103: Water - B01D 2252/204: Amines - B01D 2252/60: Additives - B01D 2256/22: Carbon dioxide - B01D 2257/504: Carbon dioxide - Y02C 20/40: of CO2 - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - Y02C: CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG] ## Abstract In an embodiment a method includes loading an absorbent with a carbon dioxide in a first device, wherein a hydrogen carbonate-containing solution is formed, feeding the hydrogen carbonate-containing solution from the first device into an electrolysis unit, electrolyzing the hydrogen carbonate-containing solution in the electrolysis unit to release carbon dioxide, wherein a carbonate-rich solution is formed in the electrolysis unit, forming oxygen, hydrogen and carbon dioxide in the electrolysis unit, and recycling the carbonate-rich solution from the electrolysis unit to the first device. ## Claims ### Claim at position 1 1-14. (canceled) ### Claim 15 A method for absorbing carbon dioxide from an air stream, the method comprising: loading an absorbent with the carbon dioxide in a first device, wherein a hydrogen carbonate-containing solution is formed; feeding the hydrogen carbonate-containing solution from the first device into an electrolysis unit; electrolyzing the hydrogen carbonate-containing solution in the electrolysis unit to release carbon dioxide, wherein a carbonate-rich solution is formed in the electrolysis unit; forming oxygen, hydrogen and carbon dioxide in the electrolysis unit; and recycling the carbonate-rich solution from the electrolysis unit to the first device. ### Claim 16 (depends on 15) The method according to claim 15, wherein the electrolysis unit comprises at least a first chamber and a second chamber, wherein the hydrogen carbonate-containing solution is fed to at least the first chamber, wherein, in the first chamber, hydrogen carbonate is consumed and at least the carbon dioxide is formed, and wherein, in the second chamber, the hydrogen carbonate is converted to carbonate to form the carbonate-rich solution. ### Claim 17 (depends on 15) The method according to claim 15, wherein the absorbent comprises an alkali carbonate component which is at least partially converted to hydrogen carbonate in the first device, wherein the hydrogen carbonate is precipitated after the conversion, wherein the precipitated hydrogen carbonate is separated, and wherein the precipitated hydrogen carbonate is used to form the hydrogen carbonate-containing solution. ### Claim 18 (depends on 17) The method according to claim 17, wherein the carbonate-rich solution has a higher carbonate content and a lower hydrogen carbonate content than the hydrogen carbonate-containing solution. ### Claim 19 (depends on 17) The method according to claim 17, wherein the precipitated hydrogen carbonate has a purity of 99±1%. ### Claim 20 (depends on 17) The method according to claim 17, wherein the absorbent is fed to the electrolysis unit after separation of the hydrogen carbonate. ### Claim 21 (depends on 15) The method according to claim 15, wherein the electrolysis unit is a two-chamber electrolysis unit with an anode chamber and a cathode chamber and the hydrogen carbonate-containing solution is fed to the anode chamber, and wherein the anode chamber and the cathode chamber are separated by a cation-selective membrane. ### Claim 22 (depends on 15) The method according to claim 15, wherein the electrolysis unit is an at least three-chamber electrolysis unit with an anode chamber, a cathode chamber, at least one middle bridge chamber, a cation-selective membrane adjacent to the cathode chamber and a bipolar membrane adjacent to the anode chamber, and wherein the hydrogen carbonate-containing solution is fed to at least one of the middle bridge chambers. ### Claim 23 (depends on 22) The method according to claim 22, wherein the hydrogen carbonate-containing solution is a pure hydrogen carbonate solution. ### Claim 24 (depends on 15) The method according to claim 15, wherein the air stream comprises a carbon dioxide concentration of greater than or equal to 100 ppm and less than or equal to 650 ppm. ### Claim 25 A device for absorbing carbon dioxide from an air stream, the device comprising: a first device configured to load an absorbent with the carbon dioxide and to form a hydrogen carbonate-containing solution; and an electrolysis unit configured to electrolyze the hydrogen carbonate-containing solution from the first device and to release carbon dioxide, wherein a carbonate-rich solution is formed in the electrolysis unit and wherein the device is configured to recycle the carbonate-rich solution from the electrolysis unit to the first device. ### Claim 26 (depends on 25) The device according to claim 25, wherein the electrolysis unit is a two-chamber electrolysis unit with an anode chamber and a cathode chamber, wherein the hydrogen carbonate-containing solution is feedable to the anode chamber, and wherein the anode chamber and the cathode chamber are separated by a cation-selective membrane. ### Claim 27 (depends on 25) The device according to claim 25, wherein the electrolysis unit is an at least three-chamber electrolysis unit with an anode chamber, a cathode chamber, at least one middle bridge chamber, a cation-selective membrane adjacent to the cathode chamber, and a bipolar membrane adjacent to the anode chamber, and wherein the hydrogen carbonate-containing solution is feedable to at least one of the middle bridge chambers. ### Claim 28 A method for absorbing carbon dioxide from an air stream, the method comprising: contacting the air stream with a carbon dioxide absorbent, wherein the carbon dioxide absorbent comprises at least: a) water in a proportion of greater than or equal to 2 wt % and less than or equal to 93 wt %; b) polyethylene glycols or polyols with a molecular weight of less than or equal to 1000 g/mol in a proportion of greater than or equal to 2 wt % and less than or equal to 93 wt %; and c) carbon dioxide absorbing agent in a proportion of greater than or equal to 5 wt % and less than or equal to 60 wt %, wherein the carbon dioxide absorbing agent comprises inorganic carbonate. ### Claim 29 (depends on 28) The method according to claim 28, wherein the carbon dioxide absorbing agent is inorganic carbonate. ### Claim 30 (depends on 28) The method according to claim 28, wherein the carbon dioxide absorbing agent is a mixture of an inorganic carbonate and at least one component selected from the group consisting of amines, polyethylene glycol amines, diaminopolyethylene glycols, carboxylic acid derivatives of polyethylene glycol amines, polyethylene imines, amine-containing sugar derivatives and amino acids. ### Claim 31 (depends on 28) The method according to claim 28, wherein the carbon dioxide absorbing agent is selected from the group consisting of potassium carbonate, sodium carbonate and mixtures of these components with a weight proportion of greater than or equal to 10 wt % and less than or equal to 50 wt % based on a total weight of the carbon dioxide absorbent, and wherein the carbon dioxide absorbent comprises an inorganic, organic or enzymatic promoter to accelerate a CO2 absorption rate. ### Claim 32 (depends on 28) The method according to claim 28, further comprising: subjecting the carbon dioxide absorbent, after contact with the air stream, to electrolysis, wherein the electrolysis is at least a three-chamber electrolysis with anode chamber, cathode chamber and middle bridge chamber with a bipolar membrane adjacent to the anode chamber, and wherein a carbon dioxide-loaded absorbent is fed at least into the middle bridge chamber. ### Claim 33 (depends on 28) The method according to claim 28, further comprising subjecting the carbon dioxide absorbent to electrolysis after contact with the air stream, wherein the electrolysis is a two-chamber electrolysis, and wherein a carbon dioxide-loaded absorbent is fed into an anode chamber. ### Claim 34 Carbon dioxide absorbent for absorbing carbon dioxide from an air stream, the carbon dioxide absorbent comprising: a) water in a proportion of greater than or equal to 2 wt % and less than or equal to 93 wt %; b) polyethylene glycols or polyols with a molecular weight of less than or equal to 1000 g/mol in a proportion of greater than or equal to 2 wt % and less than or equal to 93 wt %; and c) carbon dioxide absorbing agent in a proportion of greater than or equal to 5 wt % and less than or equal to 60 wt %, wherein the carbon dioxide absorbing agent comprises inorganic carbonate.