Process for hydroisomerization of hydrocarbons including the oxidative regeneration of catalyst employed therein

Claim 1

IN A PROCESS FOR THE HYDROISOMERIZATION OF NC5-C6 PARAFFIN HYDROCARBONS IN WHICH HYDROGEN AND HYDROCARBON FEED IN A HYDROGEN/HYDROCARBON MOL RATIO WITHIN THE RANGE FROM ABOUT 0.5 TO 5 ARE PASSED AT A TEMPERATURE OF ABOUT 650* TO 775*F. AND A PRESSURE OF ABOUT 100 TO 1000 P.S.I.G. OVER A CATALYST CONSISTING ESSENTIALLY OF 0.01-1.0% WT. OF A GROUP VIII NOBLE METAL ON AN ACIDIC REFRACTORY, MIXED-OXIDES SUPPORT SELECTED FROM THE GROUPS CONSISTING OF SILICA-ALUMINA, SILICA-ZIRCONIA, SILCATITANIA, SILICA-BORIA, AND SILICA-ALUMINA-ZIRCONIA, THE IMPROVEMENT OF USE WHICH HAS RESULTED IN CATALYST DEACTIVATION OR DEGERATION TO RESTORE SUBSTANTIALLY VIRGIN ACTIVITY BY HEATING THE CATALYST TO A TEMPERATURE OF 650* TO 950*F. FOR A PERIOD OF AT LEAST TWO HOURS IN A SUBSTANTIALLY ANHYDROUS ATMOSPHERE SELECTED FROM THE GROUP CONSISTING OF OXYGEN AND MIXTURES OF INERT GASES WITH OXYGEN AT AN OXYGEN PARTIAL PRESSURE GREATER THAN THE MINIMUM PRESSURE LINE IN THE DRAWING, WITHOUT EXPOSING SAID CATALYST TO OXYGEN AT TEMPERATURES ABOUT 950*F. REDUCING THE OXIDIZED CATALYST WITH SUBSTANTIALLY PURE HYDROGEN AT 750* TO 950*F., AND UTILIZING THE CATALYST FOR ISOMERIZATION OF NC5-C6 PARAFFIN HYDROCARBONS UNDER THE RECITED ISOMERIZATION CONDITIONS.