Process for cracking to light olefins with isomerization and/or oligomerization

Abstract

We have discovered a process for catalytic production of olefins comprising passing a feed stream to an isomerization unit to provide a first hydrocarbon stream rich in iso-paraffins. The first hydrocarbon stream is contacted with a first stream of fluid catalyst in a first reactor riser to produce a first mixture of spent catalyst and product gases. The first mixture of spent catalyst and product gases is separated into a first cracked product stream and a first stream of cool catalyst. A dilute ethylene stream is separated from the first cracked product stream which is oligomerized to produce a second hydrocarbon stream comprising C4+ oligomers. The second hydrocarbon stream is contacted with a second stream of fluid catalyst in a second reactor riser to produce a second mixture of spent catalyst and product gases.