Fluid catalytic cracking

In the process of reflexive, endothermic, non-hydrogenative cracking of hydrocarbons comprising cofeeding hot active cracking catalyst and feed hydrocarbons to a reaction zone;

• cracking said feed, coking said catalyst and cooling such in said reaction zone;
• separating cracked product from coked catalyst;
• regenerating coked catalyst by fluidizing such with an oxygen containing gas in an amount and at a temperature sufficient to burn coke off said catalyst whereby heating and reactivating said catalyst and producing a flue gas comprising carbon oxides in a regeneration zone;
• and returning said heated, reactivated catalyst to said reaction zone at predetermined temperature;
• the improvement which comprises modifying said cracking catalyst by incorporating up to about 50 parts per million of at least one platinum group metal therewith;
• providing sufficient increased oxygen to burn more carbon monoxide and to produce a flue gas containing less carbon monoxide and more carbon dioxide than would apply without sid platinum group metal whereby increasing the temperature of said regenerated catalyst above said predetermined temperature;
• maintaining a regenerator temperature high enough to support said catalyzed carbon monoxide burning;
• and cooling at least a portion of said higher temperature regenerated catalyst by indirect heat exchange with water within a cyclone separator to provide a regenerated catalyst returned to said reaction zone at about said predetermined temperature.