Influence of alkali promoters in the selective hydrogenation of 3-methyl-2-butenal over Ru/SiO{sub 2} catalysts
- Univ. of Pittsburgh, PA (United States)
The addition of potassium as a promoter to a Ru/SiO{sub 2} catalyst resulted in a striking shift in product selectivity in the hydrogenation of 3-methyl-2-butenal. The rate of hydrogenation of the C=O bond to produce the unsaturated alcohol increased concomitant with a decrease in the rate of C=C hydrogenation. IR spectroscopy showed a strong perturbation of the C=O bond for the alkali-promoted catalyst, and volumetric chemisorption and TPD results suggested that the alkali species blocked adsorption at low-coordination Ru sites. These adsorption and reaction studies suggest that polarization of the adsorbed substrate at the C=O bond is responsible for the significant shift in product selectivity upon alkali promotion. This work combines spectroscopic tools with the use of the catalytic reaction itself as a probe of catalyst surface chemistry. 40 refs., 6 figs., 3 tabs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 273607
- Journal Information:
- Journal of Physical Chemistry, Vol. 96, Issue 14; Other Information: PBD: 9 Jul 1992
- Country of Publication:
- United States
- Language:
- English
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