The influence of chlorine on the catalytic decomposition of methanol on nickel foil: Transition from poison to promoter upon modification of deposit
1985; Elsevier BV; Volume: 94; Issue: 1 Linguagem: Inglês
10.1016/0021-9517(85)90089-2
ISSN1090-2694
AutoresFriedrich Steinbach, Rüdiger Krall,
Tópico(s)Advanced Chemical Physics Studies
ResumoThe catalytic activity of a polycrystalline Ni surface with respect to the decomposition of CH3OH is completely blocked by chlorine adsorbed as Clads. CH3OH adsorbs molecularly but desorbs without any trace of a chemical reaction. After Ar sputtering at 600 K and further heating at 700 K, Clads is removed and the remaining chlorine is transformed into a nickel chloride. This comparatively small amount of nickel chloride is a promoter for the decomposition of CH3OH. The reaction occurs according to the dissociative mechanism; CH3Oads dissociates to form CH3ads and Oads, while COads, generated by dehydrogenation, dissociates to form Cads and Oads. Under equal conditions these reactions are not possible on a clean Ni surface.
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