Production of olefins

摘要

A process for the catalytic cracking of an olefin-containing feedstock which is selective towards light or olefins in the effluent, the process comprising contacting a hydrocarbon feedstock containing one or more olefins with a MFI-type crystalline silicate catalyst having a silicon/aluminium atomic ratio of at least about 180 which has been obtained by pretreating so as to increase the silicon/aluminium atomic ratio thereof by heating the catalyst in steam and de-aluminating the catalyst by treating the catalyst with a complexing agent for aluminium at an inlet temperature of from 500 to 600 DEG C and at an olefin partial pressure of from 0.1 to 2 bars to produce an effluent with an olefin content of lower molecular weight than that of the feedstock.