catalytic olefin cracking and olefin disproportionation

Considering the insufficient propylene yield of naphtha cracking and crude oil cracking FCC units, 

catalytic olefin cracking and olefin disproportionation can be used to further increase propylene production substantially.

The catalytic cracking process for increasing propylene production can further crack C4-C8 olefins.

Common processes include the Propylur process of Luqi Company, the olefin cracking process of Total and UOP, and the Superflex process of KBR.

Olefin disproportionation is to further crack olefin products such as C4. 

Common disproportionation processes include OCT process of ABB Lummus, Meta-4 process of Axens and self-disproportionation process of BASF.