Pyridine Adsorption on Molybdenum Oxide-Alumina Catalysts
نویسنده
چکیده
The adsorption of pyridine on a complete monolayer molybdenum oxide-Al203 catalyst was studied. Both Lewis and Bronsted acid sites are present on a catalyst with a Mo valence of -4.1. The orientation of adsorbed pyridine was studied by means of its interaction with surface OD groups, which leads to the formation of only 2-deuteriopyridine. The fraction of molybdenum ions active for hydrogenation reactions and that for pyridine adsorption is approximately equal to the Mo5+ content, i.e., -0.2. I t is concluded that ensembles of Mo ions of higher and lower valencies (possibly Mo5+ and Mo4+) are the sites active for the chemisorption of organic molecules and hydrogen and for hydrogenation reactions.
منابع مشابه
Investigation of the Surface Structure and Activity of Molybdenum Oxide-Containing Catalysts I. An Infrared Study of the Surface Structure of Molybdena-Alumina Catalysts
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