Catalysis and Mechanism of Hydrodenitrogenation: The Piperidine Hydrogenolysis Reaction

The chemistry of hydrodenitrogenation catalysis is discussed with special attention being focused on the nature of the catalytic sites active for piperidine hydrogenolysis and the mechanism operative in the C-N bond cleavage during piperidine conversion. Reactions such as hydrogenolysis, alkylation, cyclization, cleavage, dehydrogenation, and hydrogenation occurred when piperidine was hydrogenated over a sulfided CoMo commercial hydrocracking catalyst. Reaction mechanisms are proposed to account for the formation of the identified products from these reactions. Both acidic (Brønsted or Lewis) and basic sites are proposed to participate in the amine (such as piperidine) denitrogenation reactions.