Isomerization and hydrogenation of cis-2-butene on Pd model catalyst

Brandt B, Fischer JH, Ludwig W, Libuda J, Zaera F, Schauermann S, Freund HJ (2008)

Publication Status: Published

Publication Type: Journal article

Publication year: 2008

Journal

Journal of Physical Chemistry C American Chemical Society

Publisher: AMER CHEMICAL SOC

Book Volume: 112

Pages Range: 11408-11420

Journal Issue: 30

DOI: 10.1021/jp800205j

Abstract

The adsorption and kinetics of conversion of cis-2-butene with deuterium on model supported Pd catalyst (Pd/Fe3O4/Pt(111)) were characterized by reflection-absorption infrared spectroscopy (RAIRS), temperature-programmed desorption (TPD), and isothermal molecular beam (MB) experiments. It was found that selectivity toward cis-trans isomerization and hydrogenation depends critically on the nature of the carbonaceous deposits, which are typically present during reaction on real catalysts. At low temperatures (190-210 K) both reaction pathways were found to proceed on the initially clean surface, but the catalytic activity was observed to quickly vanish, presumably because of the accumulation of hydrocarbon species on the surface. At temperatures above 250 K, on the other hand, a sustained catalytic activity toward cis-trans isomerization was observed over long periods of time. Interestingly, no catalytic activity could be sustained for the competing hydrogenation on the initially clean catalyst even at these temperatures. Only when highly dehydrogenated carbonaceous fragments were preadsorbed on the surface was it possible to induce a persistent catalytic activity for the hydrogenation (and also the isomerization) of the alkene on our supported palladium particles. Possible reasons of this unique vacuum catalytic behavior are discussed, including different spatial requirements for the competing reaction pathways and changes in the adsorption state of deuterium on and beneath the surface modified by the carbonaceous deposits.

Authors with CRIS profile

Jörg Libuda Professur für Physikalische Chemie

Involved external institutions

Fritz-Haber-Institut der Max-Planck-Gesellschaft (FHI) DE Germany (DE) University of California, Riverside (UCR) US United States (USA) (US)

How to cite

APA:

Brandt, B., Fischer, J.-H., Ludwig, W., Libuda, J., Zaera, F., Schauermann, S., & Freund, H.-J. (2008). Isomerization and hydrogenation of cis-2-butene on Pd model catalyst. Journal of Physical Chemistry C, 112(30), 11408-11420. https://dx.doi.org/10.1021/jp800205j

MLA:

Brandt, Bjoern, et al. "Isomerization and hydrogenation of cis-2-butene on Pd model catalyst." Journal of Physical Chemistry C 112.30 (2008): 11408-11420.

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