Patent ID: 6916417

Claim:
A catalytic cracking process, comprising: introducing at least one species of a natural or synthetic residuum feedstock and a cracking catalyst into a catalytic cracker reaction zone; cracking said feedstock into a lower molecular weight gaseous product and spent cracking catalyst with hydrocarbonaceous product deposited thereon; and regenerating said spent cracking catalyst obtained from said catalytic cracker reaction zone, including; introducing said spent cracking catalyst into a first regeneration zone in a presence of a first atmosphere containing an oxygen containing gas, wherein said first regeneration zone is operated at a temperature ranging from about 1150° F. to about 1400° F. so as to reduce cracking catalyst damage resulting from higher temperature regeneration with a high moisture content atmosphere, and so as to oxidize a greater proportion of a hydrogen content than carbon content of coke associated with said spent cracking catalyst, thereby substantially reducing a water content of a subsequent regeneration zone; and introducing said spent cracking catalyst from said first regeneration zone into a second regeneration zone in a presence of a second atmosphere containing an oxygen containing gas and a carbon dioxide containing stream, wherein said second regeneration zone is operated at a temperature ranging from about 1500° F. to about 1800° F. and maintained in a partial oxidation mode, said second atmosphere, said second regeneration zone temperature and said partial oxidation mode of operation resulting in a substantial portion of said carbon dioxide of said second atmosphere to function as a reactant with carbon remaining associated with said spent cracking catalyst to form two moles of carbon monoxide per mole of carbon dioxide reacted, and thus result in a synthesis gas product rich in carbon monoxide; and recycling said regenerated cracking catalyst to said catalytic cracker reaction zone.