Catalyst reactivation process

Claim 1

AN IMPROVED PROCESS FOR THE REACTIVATION OF PLATINUM-ON-ALUMINA HYDROFORMING CATALYSTS WHICH HAVE BECOME DEACTIVATED BY THE ACCUMULATION OF CARBONACEOUS DEPOSITS THEREON DURING THE HYDROFORMING PROCESS AS WELL AS BY THE AGGLOMERATION OF THE PLATINUM INTO LARGE CRYSTALLITIES OF LOW ACTIVITY, WHICH COMPRISES STRIPPING THE SPENT CATALYST OF HYDROGEN AND HYDROCARBON MATERIALS, REGENERATING THE STRIPPED CATALYST BY CIRCULATING FLUE GAS CONTAINING A SMALL AMOUNT OF OXYGEN THROUGH THE CATALYST AT A PRESSURE OF OVER ABOUT 100 P.S.I.G. THEREBY BURNING CARBONACEOUS DEPOSITS OFF THE CATALYST AT TEMPERATURES BELOW 1050*F, WITHDRAWING FLUE GASES FROM THE CATALYST UNDERGOING REGENERATION, PASSING THE WITHDRAWN FLUE GASES THROUGH A DRIER TO REMOVE WATER FORMED DURING REGENERATION, RECYCLING THE DRIED FLUE GAS CONTAINING A SMALL AMOUNT OF OXYGEN TO THE CATALYST TO COMPLETE THE REGENERATION THEREOF, PARTIALLY REJUVENATING THE REGENERATED CATALYST BY INCREASING THE OXYGEN CONTENT OF THE DRY RECYCLE FLUE GAS STREAM TO OVER 5 MOL PERCENT, CONTINUING THE CIRCULATION OF THIS GAS STREAM AT A TEMPERATURE OF AT LEAST 900*F, AND AT A PRESSURE ABOVE ABOUT 100 P.S.I.G. OVER THE CATALYST AND THROUGH THE DRIERS FOR A PERIOD OF TIME SUFFICIENT TO DRY OUT THE SYSTEM AND PARTIALLY REJUVENATE THE CATALYST, CHLORINE TREATING THE PARTIALLY REJUVENATED CATALYST BY ADDING CHLORONE TO THE SAID RECIRCULATING REJUVENATING GAS STREAM WHILE MAINTAINING THE PRESSURE ABOVE ABOUT 100 P.S.I.G., BYPASSING SUCH A RECIRCULATING GAS STREAM AROUND THE DRIERS DURING THE CHLORINE ADDITION STEP, DISCONTINUING THE ADDITION OF CHLORINE WHEN THE TOTAL AMOUNT OF CHLORINE CHARGED IS ABOUT 0.5 TO 2.0 WT. PERCENT BASED ON THE CATALYST AND COMPLETING THE REJUVENATION OF THE CATALYST BY CONTINUING TO RECIRCULATE THE OXYGEN-CONTAINING STREAM AT A TEMPERATURE OF AT LEAST 910*F, AND AT A PRESSURE ABOVE ABOUT 100 P.S.I.G. THE TOTAL CATALYST REACTIVATION TIME BEING AT MOST ABOUT 10 HOURS.