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Iron supported on HY-zeolite and on alkali metal (Li, Na, K, Rb) ion exchanged Y-zeolite prepared by impregnation technique have been characterized by XRD, AAS, BET surface area, CO2 chemisorption, temperature programmed reduction (TPR) and temperature programmed decarburization (TPDC) techniques. These catalysts have been tested for catalytic activity for CO2 hydrogenation to hydrocarbons. The XRD patterns of Fe/HY catalysts indicate the formation of Fe2O3 monolayer at 17 wt% Fe. It is found that alkali metals exchanged in zeolite-Y increase the basicity of the catalyst surface, which influence the activity and selectivity of the catalysts in CO2 hydrogenation. The TPR profile of Fe2O3 catalyst is observed to contain only two peaks, corresponding to the reduction of Fe2O3 to Fe0 through Fe3O4. However, the TPR profiles of Fe/MY catalysts contain three peaks, which indicate the formation of iron phase through FeO phase. The peak corresponding to the reduction of Fe3O4 to FeO is observed to increase in intensity and in area and to shift to higher temperatures in the order: H |
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