Pretreatment of hydroforming catalysts

Claim 1

IN A METHOD FOR HYDROFORMING A PETROLEUM NAPHTHA IN THE PRESENCE OF AN ALUMINA-SUPPORTED PLATINUM CATALYST AT A HYDROFORMING TEMPERATURE BETWEEN ABOUT 875 AND 1000* F. AND OBTAINING THEREFROM A GASOLINE HAVING IN F-1 OCTANE NUMBER ABOVE ABOUT 90, THE IMPROVEMENT WHICH COMPRISES PRESONDITIONING THE SAID CATALYST PRIOR TO SAID HYDROFORMING OPERATION BY EXPOSING THE SAID CATALYST FOR A PERIOD OF MORE THAN ABOUT 10 HOURS TO CONTACT WITH A HYDROCARBON STOCK OF NAPHTHA BOILING RANGE UNDER HYDROFORMING CONDITIONS, INCLUDING AN HOURLY WEIGHT SPACE VELOCITY BETWEEN ABOUT 0.5 AND 5.0, AT A TEMPERATURE FROM 1K TO 75* F. BELOW THE INITIAL TEMPERATURE TO BE EMPLOYED IN THE ENSURING HYDROFORMING OPERATION, AND THEREAFTER DIRECTLY RAISING THE TEMPERATURE OF THE SAID CATALYST TO SAID INITIAL HYDROFORMING LEVEL, WHEREBY THE ACTIVITY MAINTENANCE OF THE SAID CATALYST IN THE ENSUING HYDROFORMING OPERATION IS SUBSTANIALLY IMPROVED.