Study of oxidative dehydrogenation of ethylbenzene with CO2 on supported CeO2-Fe2O3 binary oxides

Nano-sheets Al 2 O 3 supported CeO 2 -Fe 2 O 3 binary oxides were prepared by the vacuum impregnation method. The structural and textural properties were characterized by pertinent techniques, and the materials were evaluated as catalysts for the oxidative dehydrogenation of ethylbenzene with carbon dioxide (CO 2 -ODEB). The characterization results show that all samples maintain the hierarchical structure, and CeO 2 -like and Fe 2 O 3 -like solid solutions were formed when changing the Ce-to-Fe molar ratio. The catalytic performances indicate that CeO 2 -Fe 2 O 3 binary oxides were effective for CO 2 -ODEB, and the activity is determined by mobile oxygen, which can facilitate the dehydrogenation process. The DFT studies further identified the reaction pathway and rate-determining step. The inter-transmission of oxygen species and the presence of CO 2 refill the oxygen vacancies and restore the redox cycle of CeO 2 -Fe 2 O 3 binary oxides.