Nanostructured ceria-based catalysts for oxydehydrogenation of ethane with CO2

Nanostructured cerium oxides, pure or doped with CaO, prepared from amorphous acetate precursors obtained by the freeze drying method, exhibit high surface areas and are active and selective catalysts for the oxydehydrogenation of ethane (ODE) using CO₂as an oxidant. The incorporation of Ca into a solid solution in the ceria framework reduces the activity but improves markedly the selectivity to ethene and the efficiency of CO₂. Under reaction conditions, the pure ceria was stable even at 1023 K, while the surface area of the Ca-containing sample decreased markedly. This change was accompanied by a drastic increase in the selectivity to ethene, allowing to obtain yields of ethene up to 22% with 91% selectivity.