Nanostructured ceria-based catalysts for oxydehydrogenation of ethane withCO2

Nanostructured cerium oxides, pure or doped with CaO, prepared from amorpho us acetate precursors obtained by the freeze drying method, exhibit high su rface areas and are active and selective catalysts for the oxydehydrogenati on of ethane (ODE) using CO2 as an oxidant. The incorporation of Ca into a solid solution in the ceria framework reduces the activity but improves mar kedly the selectivity to ethene and the efficiency of CO2. Under reaction c onditions, the pure ceria was stable even at 1023 K, while the surface area of the Ca-containing sample decreased markedly. This change was accompanie d by a drastic increase in the selectivity to ethene, allowing to obtain yi elds of ethene up to 22% with 91% selectivity.