Abstract CO2-assisted oxidative dehydrogenation of ethane is a sustainable alternative to steam cracking for ethylene production. In this study, a series of CeO2 on SiO2 supported NiFe3 catalysts were synthesized by incipient wetness impregnation and tested for oxidative dehydrogenation performance. The CeO2/SiO2 supported catalysts with high weight loading of CeO2 (50%?75%) provided higher activity than the lower CeO2 (0%?25%) loaded catalysts (with ethylene production rates of 0.62?0.98 µmol/gcat/s and 0.19?0.3 µmol/gcat/s, respectively) while maintaining high ethylene selectivity (43%?45%). In contrast, the NiFe3 supported on only CeO2 also exhibited high activity (ethylene production rate of 0.71 µmol/gcat/s), but the ethylene selectivity (16%) was greatly decreased compared to the mixed system. Temperature programmed reduction, X-ray diffraction, and Raman spectroscopy all indicate the creation of a solid solution of the Fe and Ni doped into the CeO2 crystal structure in the catalysts with high CeO2 loading/bulk CeO2 support. The high ethylene selectivity in the high CeO2 loading catalysts indicates that the Fe is preferentially creating the solid solution, with the decrease in selectivity observed in the CeO2-only supported catalyst likely resulting from CeO2 interacting directly with Ni, creating Ni-CeOX interfaces that are known active sites for the unwanted side reaction of dry reforming.
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