CO2 adsorption performance of ZIF-7 and its endurance in flue gas components

Porous ZIF-7 with the sodalite (SOD) cage structure (ZIF, Zeolitic imidazolate framework) were synthesized by the solvothermal method. Synthesized material was characterized by powder X-ray diffraction (PXRD), thermal gravity (TG), scanning electron microscopy (SEM) and N 2 adsorption analysis. ZIF-8 with the SOD structure and a little larger pore window was synthesized in a similar way and was characterized for comparisons. Thermal stability and structural stability of ZIF-7 were tested through PXRD analysis, and the capability of the material for CO 2 capture from simulated flue gas was investigated through physical adsorption method. The results showed that CO 2 adsorption capacity on ZIF-7 was about 48 mL·g −1 while the capacity on ZIF-8 was about 18 mg·g −1 (at 12°C and 0.98 P / P 0 relative pressure). Furthermore, the impact of flue gas components on adsorption capacity of ZIF-7 and the selectivity of CO 2 against N 2 on ZIF-7 was also investigated in this work.