Dehydrogenation of alkanes to alkenes

A process for the dehydrogenation of alkanes, alkenes and/or alkylbenzenes to the corresponding unsaturated chemical products and hydrogen (H2), comprising:

• contacting a carrier gas comprising (1) one of benzene and a benzene-toluene mixture, and (2) alkane, alkene and/or alkylbenzene compounds to be dehydrogenated with a pre-sulfided metallic sulfide (MeS) catalyst, in which the dehydrogenation is conducted in one or more dehydrogenation reactors in the presence of H2S without formation of H2S as a reaction product, wherein the carrier gas further comprises:
• (1) 0.5% to less than 10% by volume steam (H2O), (2) hydrogen sulfide (H2S) at a molar ratio of H2S to the alkane, alkene and/or alkylbenzene compounds to be dehydrogenated between 0.1 and 0.2, and (3) an initial molar ratio of hydrogen sulfide to hydrogen (H2) between 0.01 and 0.2, wherein said alkane, alkene and/or alkylbenzene compounds comprise at least one of:
• (1) ethylbenzene, and (2) methane, ethane, or a combination thereof;
• and
• recovering a product stream comprising unsaturated chemical products.