Evolution of the optimal catalytic systems for the oxidative dehydrogenation of ethane: The role of adsorption in the catalytic performance

Three samples that correspond to the evolution of optimal catalytic systems for oxidative dehydrogenation ethane have been synthesized and compared in terms behavior adsorption properties: (i) vanadium oxide supported on alumina, (ii) Sn-promoted NiO, (iii) multicomponent MoVTeNbO with M1 structure. The main difference performance lies extent overoxidation ethylene formed, following order VOx/Al2O3 > NiSnOx MoVTeNb-M1. Accordingly, selectivity at medium high conversion follows MoVTeNb-M1 VOx/Al2O3. These results are confirmed by relative reaction rates observed oxidation ethylene. Microcalorimetry studies indicate heat both is highest most selective sample. Thus, low olefin decomposition catalyst not due weaker but reduced ability its active sites activate same conclusion regarding can be drawn FT-IR adsorbed On other hand, present a ability, as demonstrated notorious formation oxygenated species, precursors COx. However, rather mild because existence many free Lewis involved reaction. In contrast, case catalyst, almost all path, so olefins decompose readily.