Hydrocracking process with a crystalline zeolite catalyst composite activated with hydrogen sulfide

Claim 1

A PROCESS FOR HYDROCRACKING A HYDROCARBON FEEDSTOCK CONTAINING BOTH PARAFFINIC AND AROMATIC HYDROCARBONS, WHICH COMPRISES: (A) SUBJECTING SAID FEEDSTOCK TO A HYDROCARBON SEPARATION STEP, AND RECOVERING THEREFROM A RELATIVELY AROMATIC FEED FRACTION AND A RELATIVELY PARAFFINIC FEED FRACTION; (B) SUBJECTING SAID AROMATIC FEED RACTION PLUS ADDED HYDROGEN TO CATALYTIC HYDROCRACKING IN CONTACT WITH A CATALYST COMPRISING A CRYSTALLINE, ZEOLITIC ALUMINOSILICATE MOLECULAR SIEVE CRACKING BASE AND A SMALL PROPORTION OF A GROUP VIII METAL HYDROGENATING COMPONENT ORIGINALLY INCORPORATED INTO SAID ATALYST BY IMPREGNATION WITH A SULFIDE HYDROSOL OF SAID METAL; (C) SUBJECTING SAID PARAFFINIC FEED FRACTION PLUS ADDED HYDROGEN TO CATALYTIC HYDROCRACKING IN CONTACT WITH A CATALYST COMPRISING A CRYSTALLINE, ZEOLITIC ALUMINOSILICATE MOLECULAR SIEVE CRACKING BASE AND A SMALL PROPORTION OF A GROUP VIII METAL HYDOGENATING COMPONENT ORIGINALLY INCORPORATED INTO SAID CATALYST BY ION-EXCHANGE FROM AN AQUEOUS SOLUTION OF A SALT OF SAID METAL WHEREIN THE METAL APPEARS IN THE CATION, FOLLOWED BY SULFIDING OF THE ION-EXCHANGED COMPOSITE WITH HYDROGEN SULFIDE AT A TEMPERATURE BELOW ABOUT 200*F.;AND (D) RECOVERING DESIRED LOW-BOILING HYDROCARBONS FROM EACH OF STEPS (B) AND (C).