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Abstract

The present invention discloses a catalytic cracking process featuring at least one riser reactor, at least one stripping unit and at least one regenerator, which comprises: (a) cracking a C.sub.3-4 paraffin-rich feed in the lower section of the riser in the presence of the second component of a mixed catalyst system, the second component being zeolite Beta and/or a shape selective medium pore crystalline silicate zeolite, to provide light olefins and conversion products of light olefins including aromatics and hydrogen; (b) cracking a heavy hydrocarbon feed in an upper section of the riser in the presence of the first component of the mixed catalyst system, the first component being an amorphous cracking catalyst and/or a large pore crystalline cracking catalyst, to provide gasoline boiling range components, there being a sufficient difference between one or more physical characteristics of the catalyst components as to permit particles of first catalyst component to be separated from particles of second catalyst component in the stripping unit; (c) separating particles of spent first catalyst component from particles of second catalyst component in the stripping unit; (d) stripping the separated particles of first catalyst component; (e) conveying stripped, spent first catalyst component to the regenerator, the catalyst undergoing regeneration therein; (f) conveying regenerated first catalyst component to the upper section of the riser; (g) conveying stripped or non-stripped separated particles of second catalyst component to a reactivation zone, the catalyst undergoing reactivation therein; and, (h) conveying reactivated second catalyst component to the lower section of the riser.

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First Claim