Catalytic cracking of hydrocarbons

Claim 1

A PROCESS FOR THE CONVERSION OF HYDROCARBONS WHICH COMPRISES SEPARATING A HYDROCARBON OIL CONTAINING INTERMEDIATE AND RESIDUAL FRACTIONS OF PETROLEUM INTO A GAS OIL FRACTION AND A RESIDUAL FRACTION, SUBJECTING THE GAS OIL FRACTION TO THE ACTION OF HOT, FRESHLY REGENERATED CRACKING CATALYST AT CRACKING CONDITIONS IN A FIRST CRACKING ZONE, SEPARATING THE CATALYST FROM THE HYDROCARBONS, PASSING SEPARATED CATALYST FROM SAID CRACKING ZONE TO A FIRST REGENERATION ZONE AND THEREIN BURNING THE MAJOR PORTION, AT LEAST, OF THE CARBONACEOUS MATTER THEREFROM, WITHDRAWING REGENERATED CATALYST FROM SAID FIRST REGENERATION ZONE AND CONTACTING THE SAME WITH SAID RESIDUAL FRACTION IN A SECOND CRACKING ZONE UNDER CONDITIONS TO CONVERT A SUBSTANTIAL PORTION OF SAID RESIDUAL FRACTION INTO GASOLINE, REMOVING CONTAMINATED CATALYST FROM SAID SECOND CRACKING ZONE AND INTRODUCING THE SAME TO A SECOND REGENERATION ZONE, SEPARATELY REMOVING THE CRACKED VAPORS FROM SAID SECOND CRACKING ZONE AND SUPPLYING THE SAME DIRECTLY AND WITHOUT PRIOR PASSAGE THROUGH SAID FIRST CRACKING ZONE TO A FRACTIONATING ZONE, SEPARATING SAID GASOLINE FROM THE CRACKED VAPORS IN THE FRACTIONATING ZONE, REGENERATING SAID CONTAMINATED CATALYST IN THE SECOND REGENERATION ZONE AT HIGHER TEMPERATURE THAN THE CATALYST IN SAID FIRST REGENERATION ZONE, AND SUPPLYING HOT REGENERATED CATALYST FROM SAID SECOND REGENERATION ZONE TO SAID FIRST CRACKING ZONE.