CO₂ Capture Performance of Na₂CO₃/-Al₂O₃ Sorbent Modified with Organic Acid

Sodium-based sorbents (Na2CO3/gamma-Al2O3) hold significant potential for commercial application in CO2 capture. The key point in optimizing the sorbent is to enhance its reaction activity and adsorption capacity. This study utilized organic acids as modifiers for Na2CO3/gamma-Al2O3 sorbents and examined the performance of the sorbents in CO2 capture before and after modification. The results show that the organic acid modification plays a crucial role in adjusting the surface hydroxyl groups, reducing the grain size of the active component, and optimizing the ratio of high-index crystal surface exposure. The novel sorbent, modified with citric acid monohydrate, exhibited an exceptional reaction performance. It achieved a carbonation conversion rate of 88.9% when modified with citric acid at an equivalent ratio of 2.5, representing a substantial enhancement of 31% from the bare sample. The organic acid modification significantly contributes to optimizing the performance of sodium-based sorbents, thereby advancing their potential for practical CO2 capture applications.