Patent ID: 7375256

Claim:
A catalytic conversion process for producing light olefins with a high yield from petroleum hydrocarbons, which comprises the steps of: contacting a pre-heated petroleum hydrocarbons feedstock with a catalyst which comprises phosphorus and transition metal modified silica rich zeolite, wherein said transition metal is at least one element selected from the group consisting of Fe, Co, Ni, Cu, Zn, Mo, and Mn, having a structure of pentasil in a riser or a fluidized bed reactor, and converting under the catalytic conversion conditions to produce reaction effluent and a spent catalyst, separating the resulted reaction effluent and spent catalyst, further separating said reaction effluent into liquid products and gaseous products comprising ethylene and propylene; stripping the spent catalyst by steam; regenerating the stripped catalyst by contacting the spent catalyst with oxygen-containing gas and burning off coke; contacting the regenerated catalyst with light hydrocarbons enriched by olefins in a pre-reactor, wherein the pre-reactor is either a second riser or fluidized bed reactor other than the reactor for catalytic conversion of petroleum hydrocarbons or a portion zone in the reactor for catalytic conversion of petroleum hydrocarbons, and said catalyst has a carbon content of 0.1 -0.3% by weight; and recycling the regenerated catalyst to reactor for reuse.