Hydrocracking process

Claim 1

IN A TWO-STAGE PROCESS FOR PRODUCING VALUABLE FUEL PRODUCTS FROM A HYDROCARBON FEEL SELECTED FROM THE GROUP CONSISTING OF HYDROCARBON DISTILLATES HAVING AN INITIAL BOILING POINT OF AT LEAST 500*F. AND AN END POINT BELOW ABOUT 1100*F. AND HYDROCARBON RESIDUA BOILING ABOVE ABOUT 1050*F., WHICH COMPRISES CONVERTING IN A FIRST CONVERSION ZONE FROM 10 TO 50 VOL. PERCENT OF SAID FEED PER PASS TO FRACTIONS BOILING BELOW THE INITIAL BOILING POINT OF SAID FEED, SAID FIRST ZONE BEING OPERATED AT ABOUT 550*900*F., A SPACE VELOCITY FROM ABOUT 0.1-3.0 AND A HYDROGEN PARTIAL PRESSURE OF 1000-2500 P.S.I.G., WITHDRAWING AN EFFLUENT FROM SAID FIRST ZONE, SEPARATING SAID EFFLUENT INTO FRACTIONS IN A SEPARATION ZONE, WITHDRAWING FROM SAID SEPARATION ZONE AT LEAST ONE OF SAID FRACTIONS AS A PRODUCT, CONVERTING IN A SECOND CONVERSION ZONE AT LEAST ONE OF SAID FRACTIONS AT A CONVERSION OF AT LEAST 20 VOL. PERCENT PER PASS TO PRODUCTS BOILING BELOW THE INITIAL BOILING POINT OF SAID FRACTION PASSED TO SAID SECOND ZONE, SAID SECOND ZONE BEING OPERATED AT ABOUT 450*-850*F., A SPACE VELOCITY FROM ABOUT 0.2-5.0 AND A HYDROGEN PARTIAL PRESSURE OF AT LEAST 350 P.S.I.G. WITH A CATALYST COMPRISING A HYDROGENATING-DEHYDROGENATING COMPONENT AND AN ACTIVE ACIDIC CRACKING COMPONENT, WITHDRAWING AN EFFLUENT FROM SAID SECOND ZONE AND RECOVERING THE DESIRED PRODUCTS FROM SAID EFFLUENT, THE IMPROVEMENT WHICH COMPRISES: (A) USING AS THE CATALYST IN SAID FIRST ZONE A CATALYST COMPRISING 4-10 WT. PERCENT OF A COMPONENT SELECTED FROM THE GROUP CONSISTING OF NICKEL AND COMPOUNDS THEREOF, AND 15.5-30 WT. PERCENT OF A COMPONENT SELECTED FROM THE GROUP CONSISTING OF MOLYBDENUM AND COMPOUNDS THEREOF AND A SUBSTANTIALLY NON-ACIDIC COMPONENT ESSENTIALLY OF ALUMINA, (B) WITHDRAWING FROM SAID SEPARATION ZONE A NAPHTHA FRACTION BOILING BETWEEN C5 AND 400*F., A MIDDLE DISTILLATE FRACTION BOILING BETWEEN ABOUT 400* AND 650*F., AND A BOTTOMS FRACTION BOILING ABOVE ABOUT 650*F., (C) RECOVERING SAID NAPHTHA FRACTION AS A PRODUCT, (D) RECOVERING A PORTION OF SAID MIDDLE DISTILLATE FRACTION AS A PRODUCT, (E) PASSING AT LEAST A PORTION OF SAID BOTTOMS FRACTION AND THE REMAINDER OF SAID MIDDLE DISTILLATE FRACTION TO SAID SECOND ZONE, SAID FEED TO SAID SECOND ZONE BEING PASSED THROUGH THE ENTIRE CATALYST BED IN SAID SECOND ZONE, AND (F) RECYCLING TO SAID SECOND ZONE AT LEAST A PORTION OF SAID EFFLUENT FROM SAID SECOND ZONE BOILING ABOVE THE INITIAL BOILING POINT OF SAID FEED TO SAID SECOND ZONE.