(139c) Electrochemical Regeneration of High Purity CO2 from Carbonates for Efficient Self-Looped Carbon Capture

Capturing and concentrating low-content CO₂ in air is a crucial step for carbon neutralization and utilization. The electrochemical approach, using renewable energy as input, is a green and sustainable way to concentrate atmospheric CO₂, but is still challenged by low stability and low purity of as-captured CO₂. Herein, inspired by the charge-discharge process of chargeable batteries, we developed a module system to capture the CO₂ directly from the air and regenerate pure CO₂ through an electrochemical process. Inspired by the charge-discharge process of chargeable batteries, we proposed a close-looped process including direct air CO₂ capture, CO₂ release and the simultaneous regeneration of alkaline solutions for subsequent CO₂ absorption/desorption cycle. The three-chamber electrochemical reactor with a permeable ion-conducting solid electrolyte layer is applied, using renewable energy as input, would be a green and sustainable method to enrich atmospheric CO₂. When direct supplying carbon-containing bicarbonate/carbonate solution, a high efficiency of over 90% for hydroixde, as CO2 absorber, can be achieved. By continued cycling of the carbon-containing solution, 99% purity CO₂ gas was continuously generated with a CO₂ collection efficiency of more than 80% for over 100 h. Our design is compatible with today’s carbon neutrality aim those functions optimally with high efficiency and large compacity. The electrochemical approach, using renewable energy as input, would be a green and sustainable method to enrich atmospheric CO₂, and other materials.