The capture of carbon dioxide from flue gas of fossil-fuel combustion is the vital step incarbon sequestration，microporous zeolitic imidazolate frameworks (ZIFs), a sub-family ofmetal-organic framework of metal-organic frameworks (MOFs), have been regarded as thepromising sorbents to selectively adsorb CO2from mixed gas. Porous ZIF-7 material wassynthesized for such purposes in this study, and was characterized by powder X-ray diffraction(PXRD), thermal gravimetric (TG), scanning electron microscope (SEM), and BET technique. Forcomparison, ZIF-8 with the same SOD structure but larger pore window was also synthesized andcharacterized. Through the experiment, ZIF-7 displayed its high thermal stability and its stabilityin the presence of moisture, SO2and NO which were common flue gas components. The CO2adsorption capacity of ZIF-7 was about 48 ml/g at 0.98 P/P0 and 285 K, this amount was not thebest but among the top performance (Yazaydin, 2009) at relatively low pressure and faciletemperature. Furthermore, this capacity was not significantly influenced by pre-treating thematerial in flue gas components. The high selectivity of CO2against N2on ZIF-7 was alsoillustrated through packed bed experiment which further displayed its promising potential for CO2capture in adsorption process such as pressure swing adsorption.
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