Hydrocracking of hydrocarbons with the use of a nickel-tungsten sulfide catalyst on a siliceous carrier activated with a halogen

Claim 1

A HYDROCRACKING PROCESS PROVIDING EXTENDED CATALYST LIFE WHICH COMPRISES SUBJECTING A FEED WHICH IS PEDOMINANTLY COMPOSED OF HYDROCARBONS BOILING IN THE RANGE BETWEEN ABOUT 350* AND 800*F. WHICH IS SUBSTANTIALLY FREE OF ASPHALTIC MATERIALS AND WHCIH CONTAINS LESS THAN ABOUT 25 P.P.M. NITROGEN TO TREATMENT WITH HYDROGEN AT A TEMPERATURE BETWEEN ABOUT 400* AND 750*F. AT A PRESSURE BETWEEN ABOUT 400 AND 3000 P.S.I. WHILE IN THE PRESENCE OF A NICKEL-TUNGSTEN SULFIDE CATALYST COMPOSITED WITH A SILICA-ALUMINA CARRIER HAVING AN ACTIVITY INDEX GREATER THAN 40, SAID COMPOSITE CONTAINING ABOVE ABOUT 0.1 PERCENT COMBINED HALOGEN, AND ADDING HALOEN DURING THE TREATMENT.