The total oxidation of propane and its oxy-dehydrogenation to propene have been studied on spinel-type catalysts Mn3O4, Co3O4 and MgCr2O4 in a flow reactor and in an IR cell. Analogous studies have been performed on the oxy-dehydrogenation of n-butenes to 1,3-butadiene over MgFe2O4 Information on the reaction mechanism have been reached. The activation of the hydrocarbons is thought to occur by abstraction of a hydrogen from the weakest C-H bond, with a simultaneous reduction of a surface site and with the formation of a surface alkoxy-group.