Hydrogen utilization in fluid catalytic cracking

Claim 1

A fluidized catalytic cracking process employing a catalyst comprising a crystalline aluminosilicate, the exchangeable cationic sites of which have been ion exchanged with cations of a non-noble transitional metal, said catalyst being cycled between a cracking zone, in which said catalyst is contacted at an elevated temperature with a hydrocarbon feedstock, and a regeneration zone, in which carbon is oxidized and thereby removed from said catalyst, said process comprising subjecting said catalyst, while in transit from said regeneration zone to said cracking zone, to water thermolysis at a temperature from about 900° F. to a maximum thermal stability temperature of said catalyst and a catalyst water content of from about 0.1 wt% to about 5.0%, thereby forming hydrogen which is retained by the catalyst, introducing said hydrogen to said cracking zone with the catalyst, and releasing the hydrogen from the catalyst by contact of the latter with said hydrocarbon feedstock in the cracking zone to effect improved cracking selectivity and reduced coke production.