Journal of catalysis vol:181 issue:2 pages:265-270
The regioselective hydrogen/deuterium exchange taking place between isobutane and acidic OH groups of strong solid acids has been investigated both by in-situ solid state H-1 MAS NMR with perdeuteroisobutane and H-ZSM5 and by liquid H-1 and H-2 NMR with isobutane on various D2O-exchanged solid acids. The activation energy of the process was estimated from the variable temperature in-situ H-1 MAS NMR kinetic experiments. A drastic inhibition of the hydrogen exchange was observed in all cases when carbon monoxide was present which is rationalized by the interaction of CO with carbocationic reaction intermediates. (C) 1999 Academic Press.