Treating clay catalysts used for conversion of sulfur containing feeds

Claim 1

THE PROCESS OF CONVERTING A HYDROCARBON CHARGE STOCK CONTAINING AT LEAST 1 1/2 PER CENT SULFUR TO HYDROCARBONS OF IMPROVED MOTOR FUEL VALUE IN THE PRESENCE OF A CLAY CATALYST CONTAINING IRON COMPOUNDS AND BEING SUBJECT TO ABNORMAL AGING WHEN EMPLOYED FOR THE CATALYTIC CONVERSION OF HYDROCARBON CHARGE STOCKS CONTAINING SAID AMOUNT OF SULFUR, WHILE AT THE SAME TIME SUBSTANTIALLY OVERCOMING ABNORMAL AGING OF SAID CLAY CATALYST, WHICH COMPRISES MOVING SAID CLAY CATALYST THROUGH A CYCLIC SYSTEM COMPRISING A CONVERSION ZONE WHEREIN THE CATALYST IS CONTACTED WITH SAID CHARGE AT ELEVATED CRACKING TEMPERATURES EFFECTIVE TO ACCOMPLISH CONVERSION OF THE CHARGE AND TO CONVERT IRON COMPOUNDS IN SAID CLAY CATALYST TO IRON SULFIDE WHILE CAUSING THE CONCOMITANT FORMULATION OF A CARBONACEOUS DEPOSIT ON THE CATALYST, AND THROUGH A REGENERATION ZONE WHEREIN THE CATALYST IS CONTACTED WITH AN OXYGENCONTAINING GAS UNDER CONDITIONS EFFECTIVE TO BURN OFF THE CARBONACEOUS DEPOSIT, WITHDRAWING A PORTION OF THE CATALYST DURING ITS CYCLE OF MOVEMENT, REMOVING FROM SUCH PORTION IRON COMPOUNDS CHEMICALLY CONVERTED DURING SAID CYCLE, AND RETURNING THE RESULTING CATALYST TO THE SYSTEM.