Patent ID: 6258990
Filing Date: 2001-07-10
Classification: C10G

Abstract:
A process for producing polypropylene comprising the steps of:(a) feeding steam and a naphtha feed containing between about 10 and 30 wt. % paraffins and between about 15 and about 70 wt. % olefins into a reaction zone;(b) contacting the naphtha feed with a catalyst comprising 10 to 50 wt. % of a crystalline zeolite having an average pore diameter less than about 0.7 nm at conditions including a temperature from about 500.degree. C. to 650.degree. C., a hydrocarbon partial pressure of 10 to 40 psia, a hydrocarbon residence time of 1 to 10 seconds, and a catalyst to feed weight ratio of about 4 to about 10, wherein no more than about 20 wt. % of paraffins are converted to olefins, wherein propylene comprises at least about 90 mol. % of the total C.sub.3 products; and,(c) separating the propylene from the C.sub.3 products and polymerizing the propylene to form polypropylene.