Abstract:
The integrated capture and catalytic conversion of CO
2 from industrial flue gas is a current research focus. Metal-organic frameworks (MOFs) are widely used in CO
2 adsorption and separation. To enhance the water stability of a copper-based MOF adsorbent-catalyst, a structure-directing agent (AspCuTEA) was employed to modulate its synthesis. This AspCuTEA was further integrated with hydrophobic carbon aerogel (CCA) to co-regulate the structure of a composite adsorbent-catalyst (AspCuTEA-CCA), aiming to improve its performance for both CO
2 adsorption and conversion. In a cyclic fixed-bed system, the AspCuTEA-CCA was first used for CO
2 adsorption and separation. Subsequently, the adsorbed CO
2 was directly utilized for the cycloaddition reaction with epichlorohydrin to produce cyclic carbonate without a desorption step. Adsorption results showed that the AspCuTEA-CCA achieved saturated CO
2 capacities of 386 mg/g for pure CO
2 and 198 mg/g for a 15% CO
2 mixture. Notably, the presence of a small amount of water vapor enhanced CO
2 uptake. The direct catalytic conversion of the adsorbed CO
2 into cyclic carbonate reached a yield of 93.6%. The AspCuTEA-CCA maintained its structural integrity over 10 adsorption-desorption cycles and 3 catalytic conversion cycles, demonstrating excellent structural stability and consistent performance, indicating promising potential for industrial application.