a catalytic cracking process for converting heavy , metals laden feed to lighter products is disclosed . the catalyst regenerator is operated under relatively reducing conditions , to produce a flue gas containing at least 1 mole % carbon monoxide . an additive , preferably alumina , is added to the circulating catalyst inventory to selectively sorb metal contaminants in the feed . the reducing conditions in the catalyst regenerator minimize formation of highly oxidized forms of vanadium , permitting higher vanadium levels to be tolerated on the cracking catalyst . the additive material has a greater affinity for vanadium than the cracking catalyst , and absorbs a disproportionate amount of metals in the feed . preferably a soft , friable , alumina additive is used which results in the production of alumina fines rich in vanadium , which are discharged from the unit with catalyst fines . the process works especially well in fluidized catalytic cracking processes , with removal of vanadium laden alumina fines from the fcc regenerator with the regenerator flue gas .