Abstract:
Under the dual strategic background of “carbon peaking and carbon neutrality”, CO
2 capture has become an important task at present. Solid adsorbent adsorption is widely used in CO
2 capture process, among which SiO
2 aerogel has the advantages of low cost, flexible synthesis method, high separation efficiency, easy surface modification, etc. However, SiO
2 aerogel materials also have some defects, such as low CO
2/N
2 adsorption selectivity and CO
2 adsorption capacity to be further improved. To address the above issues, this article has prepared a Cu-BTC@SiO
2 Composite aerogel CO
2 adsorption material. Firstly, the surface chemistry and pore structure were systematically characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and nitrogen adsorption and desorption tests. Then, the CO
2 adsorption capacity, selective adsorption, and cyclic adsorption were studied through carbon dioxide adsorption testing. Finally, a combination of theoretical and experimental research was used to study the CO
2 adsorption kinetics of the adsorbent. The results show that the SiO
2 aerogel compounded with Cu BTC has a high specific surface area of 726.431 m
2/g, a specific surface area of 570.781 m
2/g, and a high microporous volume of 0.184 cm
3/g. After loading tetraethylenepentamine(TEPA), the adsorption capacity of CO
2 is up to 2.95 mmol/g, and the selective adsorption is 40.8, after 10 cycles of CO
2 adsorption, the adsorption capacity decreased slightly. Therefore, TEPA-modified Cu-BTC@SiO
2 composite aerogels can significantly improve the CO
2 adsorption performance of SiO
2 aerogels. The metal organic framework material Cu BTC with rich micropore structure is compounded with SiO
2 aerogel, and is prepared by the sol gel method Cu-BTC@SiO
2 Composite aerogel to make the composite have hierarchical micro/mesoporous structure and enhance the physical adsorption of CO
2 by enhancing the intermolecular force (van der Waals force); The material is impregnated with TEPA, and the chemical adsorption of CO
2 is enhanced by acid-base interaction between organic amine and acid gas.