Amine-functionalized mesoporous monolithic adsorbents for post-combustion carbon dioxide capture

Amine-functionalized solid adsorbents have significant application potential in post-combustion CO2 capture due to the advantages of high capacity, low regeneration cost and long-term stability. Although the powdery adsorbents exhibit higher CO2 uptake capacity, the poor strength and large pressure drop limit their practicability. Monolithic adsorbent is considered as a good choice to solve these problems, but still facing the bottle-neck of insufficient CO2 capacity. In this work, a facile and feasible gel-casting method was proposed to fabricate monolithic adsorbents with high CO2 capacity, excellent mechanical strength, and good cycling stability. MCM41 with rich mesoporous structure was immobilized by polymerization of organic polymer to construct monolithic adsorbents supports with high specific surface area (similar to 1088 m(2) g(-1)) and mechanical strength. The 70TMM-550 monolithic adsorbent impregnated with TEPA achieved high adsorption capacity of 151.1 mg g(-1) at 75 degrees C under 1 atm pure CO2. The monolithic adsorbents also showed good reversibility of CO2 adsorption under mild conditions, where the adsorption capacity decreased only by 2.8% after five regeneration cycles. In addition, the radial and axial compressive strength of 70T-MM-550 is over 200 N cm(-1) and 4.5 MPa, respectively. In consideration of the high CO2 capture performance and mechanical properties of the monolithic adsorbents, the findings here open a new avenue for designing efficient monolithic CO2 adsorbents with industrially potential.

Automated summary

This study proposed a simple and effective gel-casting method to fabricate monolithic adsorbents with high CO2 capacity, excellent mechanical strength, and good cycling stability.