Improved Catalytic Performance of Ethane Dehydrogenation in the Presence of CO(2) over Zr-Promoted Cr/SiO(2)

[Image: see text] The Zr-, Ce-, Sr-, and Sn-promoted Cr/SiO(2) catalysts were prepared by the incipient wetness impregnation method, then characterized by N(2) adsorption/desorption, X-ray diffraction, X-ray photoelectron spectroscopy, H(2)-TPR, CO(2)-TPD, UV–vis, high-angle annular dark-field imaging–scanning transmission electron microscopy—energy dispersive X-ray spectroscopy elemental mapping, Raman, and thermogravimetric techniques to study the structural evolution under the preparation/reaction conditions, and applied to catalyze ethane oxidative dehydrogenation with CO(2). The results suggested that the Cr(6+) species were indispensable for activating the dehydrogenation reaction thanks to the oxidation–reduction cycle between Cr(6+) and Cr(3+). The type of the promotor also affected significantly the ability of replenishing the lattice oxygen through the disassociation of CO(2), leading to the different catalytic performances. The Zr-promoted sample had the best performance in converting the reactants as well as the catalytic stability.