{sup 13}C NMR studies of ethylene adsorbed on Ru-Y zeolite
- Rensselaer Polytechnic Inst., Troy, NY (United States)
The adsorption of ethylene on reduced co-cation-exchanged Ru-Y zeolites has been studied with {sup 13}C solid-state NMR. Self-hydrogenation of ethylene to ethane and butane is observed at room temperature. 2-Butenes are intermediates in the reaction. Coadsorption of hydrogen and ethylene leads to an increase in the rate of hydrogenation, with the initial rate being roughly first order in hydrogen overpressure. The rate follows a co-cation dependence in the order Ru-H-Y > Ru-Ca-Y > Ru-Na-Y. At intermediate temperatures some butane isomerizes to isobutane in all zeolites studied, presumably through a carbocation intermediate formed at the acid sites either inherent in Ru-H-Y or created upon reduction of the metal in Ru-Ca-Y and Ru-Na-Y. At temperatures above 623 K, carbon-carbon bond cleavage is complete yielding only methane. Following evacuation of samples, signals from residual carbon are observed in the alkyl region, but are not well resolved. 27 refs., 12 figs., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 263248
- Journal Information:
- Journal of Physical Chemistry, Journal Name: Journal of Physical Chemistry Journal Issue: 6 Vol. 96; ISSN JPCHAX; ISSN 0022-3654
- Country of Publication:
- United States
- Language:
- English
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