An acid component removal device for removing an acid component from an acid gas absorbent containing an amine, comprising: an anode; a cathode; and an electrodialysis structure having four compartments formed by arranging an first membrane which is either an anion exchange membrane or a cation exchange membrane, a second membrane which is a bipolar membrane, and a third membrane which is either an anion exchange membrane or a cation exchange membrane and which is the other of the first membrane, in this order, from the anode end to the cathode end between the anode and the cathode, with a space each between the membranes.

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.

Processes and apparatus for electrocatalytically converting carbon dioxide emissions and/or ambient carbon dioxide into useful chemicals are described. The process may include: removing carbon dioxide from ambient air through a carbon capture technique, supplying a carbonate or bicarbonate aqueous solution as cathode feed to a cathode of an electrolytic cell comprising a membrane electrode assembly which includes a bipolar membrane separating an anode from the cathode, and applying an electrical potential difference between the cathode and the anode of the membrane electrode assembly to electrocatalytically reduce the carbonate or bicarbonate aqueous solution to carbon monoxide or another useful chemical.

Systems and methods for at least partially removing carbon dioxide (CO.sub.2) from a feed gas comprising CO.sub.2 are generally provided.

Disclosed herein are methods of electrochemically enhanced amine-based CO.sub.2 capture and systems for performing the methods of amine-based CO.sub.2 capture. The present methods and systems advantageously may be carried out at ambient temperatures and allow for reusing the amine through multiple cycles.

A method for capturing and sequestering carbon dioxide (CO.sub.2) includes receiving and performing an electrochemical process on the input liquid including water and a salt to produce at least one hydroxide-rich stream, and then capturing CO.sub.2 from air using the hydroxide-rich stream and a passive air capture system, thereby producing a liquid carbonate solution containing air-captured CO.sub.2. Optional steps include disposing of the liquid carbonate solution, precipitating air-captured CO.sub.2 from the liquid carbonate solution as solid carbonate and/or a slurry of carbonate, and mixing the liquid carbonate solution with a hydrogen-rich stream produced by the electrochemical process to generate gaseous CO.sub.2. Various integrations and synergies among CO.sub.2 capture, renewable energy, water desalination, and metal and mineral extraction are provided.

The invention concerns a process and modular system for producing formic acid from a source of carbon dioxide. The process according to the invention comprises (a) a carbon capture step wherein a source of carbon dioxide is contacted with an alkaline solution to obtain a solution comprising carbonate and/or bicarbonate; optionally (b) subjecting the solution comprising carbonate and/or bicarbonate to alkaline water electrolysis, wherein carbonate present in the solution comprising carbonate and/or bicarbonate is converted to bicarbonate and H.sub.2O is converted into H.sub.2 and O.sub.2; (c) subjecting the solution comprising carbonate and/or bicarbonate to a hydrogenation step in the presence of a catalyst to obtain a solution comprising formate; and (d) subjecting the solution comprising formate obtained in step (c) to bipolar membrane electrodialysis to obtain a concentrated formic acid solution and a recovered alkaline solution, wherein the recovered alkaline solution obtained in step (d) is recycled back to step (a). The concentrated formic acid solution obtained from step (d) may be subjected to a hydrogenation step in the presence of a hydrogenation catalyst to obtain a concentrated formaldehyde solution.

A method for capturing and sequestering carbon dioxide (CO.sub.2) includes receiving and performing an electrochemical process on the input liquid including water and a salt to produce at least one hydroxide-rich stream, and then capturing CO.sub.2 from air using the hydroxide-rich stream and a passive air capture system, thereby producing a liquid carbonate solution containing air-captured CO.sub.2. Optional steps include disposing of the liquid carbonate solution, precipitating air-captured CO.sub.2 from the liquid carbonate solution as solid carbonate and/or a slurry of carbonate, and mixing the liquid carbonate solution with a hydrogen-rich stream produced by the electrochemical process to generate gaseous CO.sub.2. Various integrations and synergies among CO.sub.2 capture, renewable energy, water desalination, and metal and mineral extraction are provided.

An atmospheric CO.sub.2 capture system includes a compartment housing a solid CO.sub.2 sorbent, an exchange fluid including a chemical component with selectivity towards CO.sub.2, and an electrochemical cell in fluid communication with the compartment, the system having a cycle including a first state of sorbing CO.sub.2 from incoming air onto the solid CO.sub.2 sorbent until a saturation point is reached; a second state of regenerating the sorbent by flooding the compartment with the exchange fluid to detach CO.sub.2 from the saturated sorbent and bind the detached CO.sub.2 to the chemical component; and a third state of regenerating the chemical component by detaching CO.sub.2 from the chemical component in the electrochemical cell and releasing the CO.sub.2 from the system.

An atmospheric CO.sub.2 capture system includes a compartment housing a solid CO.sub.2 sorbent, an exchange fluid including a chemical component with selectivity towards CO.sub.2, and an electrochemical cell in fluid communication with the compartment, the system having a cycle including a first state of sorbing CO.sub.2 from incoming air onto the solid CO.sub.2 sorbent until a saturation point is reached; a second state of regenerating the sorbent by flooding the compartment with the exchange fluid to detach CO.sub.2 from the saturated sorbent and bind the detached CO.sub.2 to the chemical component; and a third state of regenerating the chemical component by detaching CO.sub.2 from the chemical component in the electrochemical cell and releasing the CO.sub.2 from the system.