Abstract: A cracking catalyst used to crack oil to produce gasoline or higher-boiling hydrocarbon fuel is contacted with both (A) antimony or a compound thereof such as antimony tris(0,0-dipropyl phosphorodithioate) and (B) a modifying composition consisting essentially of carbon, hydrogen, nitrogen, and sulfur produced by the treatment of a metal salt of a dialkyl dithiocarbamate with a hydrolyzable germanium (IV) compound such as germanium tetrachloride, the contacting of the catalyst with (A) and (B) prior to, during, or after use of the catalyst in a cracking process being effective in precluding or reducing adverse effects of metals such as nickel, vanadium, and iron.

Abstract: A cracking catalyst used to crack oil to produce gasoline or higher-boiling hydrocarbon fuel is contacted with both (A) antimony or a compound thereof such as antimony tris(O,O-dipropyl phosphorodithioate) and (B) a modifying composition consisting essentially of carbon, hydrogen, nitrogen, and sulfur produced by the treatment of a metal salt of a dialkyl dithiocarbamate with a hydrolyzable germanium (IV) compound such as germanium tetrachloride, the contacting of the ctalyst with (A) and (B) prior to, during, or after use of the catalyst in a cracking process being effective in precluding or reducing adverse effects of metals such as nickel, vanadium, and iron.