Patent ID: 8921632

Claim:
A light olefins synthesis process comprising: (a) passing an oxygenate feed to an oxygenate-to-olefin reactor to contact the oxygenate feed with a molecular sieve catalyst and to convert oxygenate feed to light olefins which are discharged from the oxygenate-to-olefin reactor in an effluent stream; (b) separating the effluent stream into a first light olefins stream separate from a first stream containing C4 and higher hydrocarbons; (c) selectively hydrogenating and then cracking the first stream containing C4 and higher hydrocarbons to form a first cracked gas effluent stream containing light olefins; (d) separately cracking a hydrocarbon stream to form a second cracked gas effluent stream containing light olefins; (e) co-fractionating the first and second cracked gas effluent streams to produce a second light olefins-containing stream separate from a second stream containing C4 and higher hydrocarbons; (f) co-conditioning the first and second light olefins-containing streams to remove acid gases and produce a conditioned stream; and (g) separating the conditioned stream into an ethylene product stream, a propylene product stream and a stream containing C4 hydrocarbons and (h) optionally selectively hydrogenating the stream containing C4 hydrocarbons and then fractionating the optionally selectively hydrogenated stream to separate a 2-butene stream from a first 1-butene stream.