Manganese-Promoted Fe3O4 Microsphere for Efficient Conversion of CO2 to Light Olefins

In this work, manganese well-dispersed on Fe 3 O 4 microsphere (Mn–Fe 3 O 4 ) catalyst was synthesized. It exhibited excellent catalytic performance for the direct conversion of carbon dioxide (CO 2 ) into light olefins. A CO 2 conversion of 44.7% with high selectivity of light olefin (46.2%, yield of 18.7%), high O/P ratio (6.5), and low selectivity of CO (9.4%) was obtained over the 10Mn–Fe 3 O 4 catalyst. The Mn–Fe 3 O 4 catalyst was studied by XRD, SEM, (HR)TEM, STEM–EDS, H 2 -TPR, and CO 2 -TPD. The result indicated that the manganese promoter could facilitate the adsorption of CO 2 and the activation of C═O bonds as well as inhibit the secondary hydrogenation. This work offered a novel Fe-based catalyst system to the utilization of CO 2 and an understanding in promoting C═O bond activation in the first step of CO 2 hydrogenation to hydrocarbon reaction.