Mechanistic effects resulting from the cesium-doping of a NiMoO4 catalyst in n-butane oxidative dehydrogenation

Abstract In this paper, the catalytic n- butane oxydehydrogenation was studied over two catalysts: undoped and Cs-doped α-NiMoO 4 . The effects of both reaction temperature and contact time on the catalytic performances were evaluated, providing a further insight about the reaction network. It is shown that 1-butene and 2-butenes isomers are primary products, being butadiene formed through a consecutive dehydrogenation step via any n -butene. Carbon oxides are also secondary products, resulting from the deep oxidation of any hydrocarbon species, but direct oxidation of butane must also be considered, particularly to CO 2 . The effects of cesium-doping are an increase in the butenes production with a simultaneous inhibition of the deep oxidation to CO x species, practically not affecting the butenes to butadiene dehydrogenation step.