Patent ID: 7102050

Claim:
An oxygenate to olefin conversion process comprising: (a) feeding an oxygenate feed to a plurality of necks, each neck having a head extending into an associated riser reactor, wherein each riser reactor extends into a shell and into a separation zone of a single hydrocarbon conversion apparatus; (b) reacting said feed by contacting with a non-zeolitic molecular sieve catalyst from a catalyst retention zone in a mouth of each riser reactor at a gas superficial velocity of greater than 1 meter per second at any point in the conversion apparatus, wherein each head extending into each riser is positioned at or above the mouth, and the reaction of said feed produces a light olefin product; (c) separating said catalyst from said product in the separation zone; (d) transporting a portion of said catalyst from said shell of the separation zone to a regenerator apparatus; (e) moving a portion of said catalyst from said shell of the separation zone to the catalyst retention zone by way of a catalyst return that defines at least a portion of the catalyst retention zone; and (f) returning catalyst from the regenerator apparatus to the separation zone, the catalyst retention zone, the catalyst return or any combination thereof.