Combined catalytic cracking and catalytic hydrocracking

Claim 1

A PROCESS FOR PRODUCING GASOLINE FROM CRUDE OIL WHICH COMPRISES (A) FRACTIONATING SAID CRUDE OIL TO PRODUCE AT LEAST A GAS OIL AND A TOPPED CRUDE, (B) CATALYTICALLY CRACKING SAID TOPPED CRUDE, (C) CATALYTICALLY CRACKING IN A SEPARATE CRACKING ZONE FROM THAT OF STEP "B" SAID GAS OIL, (D) COMBINING THE CRACKED EFFLENTS OF STEPS "B" AND "C", (E) FRACTIONATING THE THUS-COMBINED EFFLUENTS TO PRODUCE A C3 AND LIGHTER STREAM, A GASOLINE PRODUCT STREAM, AND A CYCLE OIL STREAM, (F) SOLVENT EXTRACTING SAID CYUCLE OIL STREAM TO PRODUCE A RAFFINATE COMPRISING PARAFFINS AND AN EXTRACT COMPRISING AROMATICS, (G) RECYCLING SAID RAFFINATE TO THE FEED OF THE CATALYTIC CRACKING OF STEP "C", (H) FRACTIONING SAID EXTRACT TO PRODUCE A LIGHT EXTRACT OIL HAVING AN END POINT IN THE RANGE OF ABOUT 500*F. TO ABOUT 600*F. AND A HEAVY EXTRACT OIL COMPRISING THE REMAINDER OF SAID EXTRACT, (I) CONTACTING SAID LIGHT EXTRACT OIL WITH SAID C3 AND LIGHTER STREAM OF STEP "E" TO PRODUCE A HYDROGENRICH GAS STREAM AND A LIGHT-HYDROCARBON-ENRICHED LIGHT EXTRACT OIL, (J) FLASHING SAID LIGHT-HYDROCARBON-ENRICHED LIGHT EXTRACT OIL TO PRODUCE A LIGHT HYDROCARBON PRODUCT STREAM AND A DENUDED EXTRACT OIL, (K) COMBINING SAID HEAVY EXTRACT OIL WITH SAID DENUDED EXTRACT OIL, (L) CATALYTICALLY HYDROCRACKING THE COMBINED STREAM OF STEP "K" IN THE PRESENCE OF HYDROGEN-RICH GAS FROM STEP "I", AND (M) SEPARATING FROM THE HYDROCRACKED STREAM OF STEP "L" ADDITIONAL GASOLINE PRODUCT.