Dehydrogenation process

A process for dehydrogenating light alkanes comprising the steps of:

• (a) contacting a feed stream comprising at least one alkane having from 2 to 5 carbon atoms per molecule in a reactor with steam and a catalyst composition comprising (i) at least one aluminate spinel selected from the group consisting of Group IIA metal aluminates and Group IIB metal aluminates, (ii) at least one metal selected from the group consisting of nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum, and (iii) at least one compound of a metal selected from the group consisting of germanium, tin and lead, under such dehydrogenation conditions as to at least partially convert said at least one alkane to at least one alkene;
• (b) discontinuing the flow of said feed stream through said reactor containing said catalyst composition, and passing a purge gas stream selected from the group consisting of steam, at least one inert gas and mixtures of steam and at least one inert gas through said reactor, so as to substantially remove hydrocarbons from said reactor;
• (c) thereafter contacting said catalyst composition in said reactor, with steam and a free oxygen containing gas stream, under such regeneration conditions as to substantially burn off carbonaceous deposits on said catalyst composition and to obtain a regenerated catalyst composition;
• (d) discontinuing the flow of the free oxygen containing gas stream through said reactor containing said regenerated catalyst composition, and passing a purge gas stream, as described in step (b), through said reactor so as to substantially remove free oxygen from said reactor;
• (e0 contacting said regenerated catalyst composition in said reactor with a reducing gas stream comprising free hydrogen and steam, under such conditions as to obtain a reactivated catalyst composition, wherein the molar ratio of steam to free hydrogen in said reducing gas stream is in the range of from about 2:1 to about 20:1;
• and
• (f) discontinuing the flow of free hydrogen through said reactor and contacting said feed stream in said reactor with steam and the reactivated catalyst composition obtained in step (e), under such dehydrogenation conditions as to at least partially convert said at least one alkane to at least one alkene.