The present disclosure provides systems and methods useful in capture of one more moieties (e.g., carbon dioxide) from a gas stream (i.e., direct air capture). In various embodiments, the systems and methods can utilize at least a scrubbing unit, a regeneration unit, and an electrolysis unit whereby an alkali solution can be used to strip the moiety (e.g., carbon dioxide) from the gas stream, the removed moiety can be regenerated and optionally purified for capture or other use, and a formed salt can be subjected to electrolysis to recycle the alkali solution back to the scrubber for re-use with simultaneous production of one or more further chemicals.

A system of utilizing carbon dioxide comprises a carbon dioxide capturing device for capturing carbon dioxide, an electrochemical reaction device for producing synthetic gas by reducing the carbon dioxide captured by the carbon dioxide capturing device, a hydrogen carrier manufacturing device for manufacturing a hydrogen carrier material by using the synthetic gas produced by the electrochemical reaction device, a dehydrogenation device for producing hydrogen from the hydrogen carrier material manufactured by the hydrogen carrier manufacturing device, and a hydrogen utilization device for utilizing hydrogen produced by the dehydrogenation device, wherein the dehydrogenation device further produces carbon dioxide from the hydrogen carrier material and supplies the carbon dioxide to the carbon dioxide capturing device.

Techniques according to the present disclosure include capturing carbon dioxide from a dilute gas source with a CO.sub.2 capture solution to form a carbonate-rich capture solution; separating at least a portion of carbonate from the carbonate-rich capture solution; forming an electrodialysis (ED) feed solution; flowing a water stream and the ED feed solution to a bipolar membrane electrodialysis (BPMED) unit; applying an electric potential to the BPMED unit to form at least two ED product streams including a first ED product stream including a hydroxide; and flowing the first ED product stream to use in the capturing the carbon dioxide from the dilute gas source with the CO.sub.2 capture solution.

A direct air capture (DAC) system for removal of carbon dioxide from ambient air has a reaction chamber having an air intake opening and an air exhaust opening, an air movement mechanism positioned to move air from outside through the reaction chamber, utilizing the air intake and the air exhaust openings, and a mechanism introducing sodium hydroxide into the reaction chamber. Carbon dioxide in the air moved through the reaction chamber interacts chemically with the sodium hydroxide, producing sodium carbonate and water.

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.

In an embodiment, a method for recovering carbon dioxide comprises introducing a carbon dioxide rich stream to a scrubber comprising a metal hydroxide and allowing the carbon dioxide to react with the metal hydroxide to form a metal carbonate; directing a metal carbonate stream from the scrubber to an electrochemical concentrator and applying a potential to the electrochemical concentrator to form a metal hydroxide stream and a separated carbon dioxide stream; directing the metal hydroxide stream comprising a recovered metal hydroxide and hydrogen to an electrochemical separator and applying a potential to the electrochemical separator to separate the hydrogen forming a hydrogen recycle stream from the recovered metal hydroxide forming a metal hydroxide recycle stream; and directing the separated carbon dioxide stream to a gas liquid separator and separating the separated carbon dioxide stream into a recycled water stream and a concentrated carbon dioxide stream.

Methods and apparatus incorporating porous metallic electrodes for electrolytic conversion of carbon-containing ions are disclosed. A electrochemical cell has an anode, a porous metallic electrode which serves as a cathode, and an ion exchange membrane between the anode and the porous metallic electrode. Water dissociates into hydroxide ions and hydrogen ions at the ion exchange membrane. The hydroxide ions permeate towards the anode, and the hydrogen ions permeate towards the porous metallic electrode. A carbon-containing solution is supplied to the porous metallic electrode. The carbon-containing solution reacts with the hydrogen ions to form one or more carbon-containing intermediate products. One of the carbon-containing intermediate products participate in a reduction reaction at the porous metallic electrode to form one or more carbon-containing resulting products. In some embodiments, the carbon-containing solution comprises a solution containing bicarbonate. One application of the methods and apparatus is in the field of carbon capture.

The present disclosure provides a system for capturing carbon from air based on bipolar membrane electrodialysis, which includes a first cation exchange membrane, a bipolar membrane and a second cation exchange membrane arranged in sequence, where a desorption chamber is arranged between the first cation exchange membrane and the bipolar membrane, and an absorption chamber is arranged between the bipolar membrane and the second cation exchange membrane; and a cathode reaction chamber is arranged on the other side of the first cation exchange membrane, and an anode reaction chamber is arranged on the other side of the second cation exchange membrane. The system improves carbon capture rate and capture purity, and can be adapted to various scenarios.

The present disclosure relates to a device and method based on an electrically-driven chemical carbon pump combined cycle for a diluted carbon source. The device includes: an electrolytic cell and a cell structure. The electrolytic cell includes a cathode reaction chamber, a CO.sub.2 desorption chamber, a CO.sub.2 absorption chamber, and an anode reaction chamber that are connected in sequence. The CO.sub.2 desorption chamber and the CO.sub.2 absorption chamber are communicated through a bipolar membrane (BPM). The cell structure includes: a negative electrode, a positive electrode, a positive region, and a negative region. The negative electrode is arranged in the negative region, and the positive electrode is arranged in the positive region. The negative electrode is connected with the cathode reaction chamber, and the positive electrode is connected with the anode reaction chamber. A liquid outlet of the negative region is communicated with a liquid inlet of the cathode reaction chamber. A liquid inlet of the negative region is communicated with a liquid outlet of the cathode reaction chamber. A liquid outlet of the positive region is communicated with a liquid inlet of the anode reaction chamber.

An integrated system for capturing carbon dioxide and sulfur oxides from a flue gas stream comprising a desulfurization chamber to remove sulfur-type pollutants and a carbon dioxide capture system in fluid communication with the desulfurization chamber; where the carbon dioxide capture system is operative to absorb carbon dioxide from the flue gas stream.