A process for the production of propylene from an olefinic feedstock containing
at least one olefin of C4 or greater, the process comprising contacting
the olefinic feedstock with a catalyst of the MFI-type having a silicon/aluminum
atomic ratio of at least about 180 to produce an effluent containing propylene,
the propylene yield on an olefin basis being from 30 to 50k based on the
olefinic content of the feedstock.