Oxidative dehydrogenation process with hydrocarbon moderator gas and reduced nitrogen feed

A method of producing butadiene from an ethylene raw material feed comprising:

• (a) providing ethylene to a homogeneous reaction medium housed in a dimerization reactor;
• (b) dimerizing ethylene to n-butene in the homogeneous reaction medium to provide a hydrocarbonaceous n-butene rich feed;
• (c) mixing said hydrocarbonaceous butene rich feed with steam, oxygen and a hydrocarbon moderator gas to form an oxidative dehydrogenation reactor feed stream and superheating said oxidative dehydrogenation reactor feed stream to a temperature of at least 204° C. (400° F.), wherein the molar ratio of hydrocarbon moderator gas to oxygen in the feed stream is from 8:1 to 0.5:1;
• (d) feeding the an oxidative dehydrogenation reactor feed stream to an oxidative dehydrogenation reactor;
• (e) oxidatively dehydrogenating the n-butene reactant in the oxidative dehydrogenation reactor to generate an effluent product stream enriched in butadiene derived from said n-butene;
• and
• (f) recovering said butadiene from the effluent product stream.

A method of co-producing butene-1 and butadiene from an ethylene raw material feed comprising:

• (a) providing ethylene to a homogeneous reaction medium including a homogeneous titanium/aluminum catalyst housed in a dimerization reactor;
• (b) dimerizing ethylene predominantly to butene-1 in the homogeneous reaction medium to provide (i) a hydrocarbonaceous butene-1 rich feed and (ii) a butene-1 rich product stream;
• (c) withdrawing and purifying the butene-1 rich product stream and recovering butene-1 therefrom;
• (d) mixing said hydrocarbonaceous butene rich feed with steam, oxygen and a hydrocarbon moderator gas to form an oxidative dehydrogenation reactor feed stream and superheating said oxidative dehydrogenation reactor feed stream to a temperature of at least 204° C. (400° F.), wherein the molar ratio of hydrocarbon moderator gas to oxygen in the feed stream is from 8:1 to 0.5:1;
• (e) feeding the an oxidative dehydrogenation reactor feed stream feed stream to an oxidative dehydrogenation reactor;
• (f) oxidatively dehydrogenating the n-butene in oxidative dehydrogenation reactor to generate an effluent product stream enriched in butadiene derived from said n-butene;
• and
• (g) recovering said butadiene from the effluent product stream.