Metal-oxygen bond strength of oxides and their catalytic properties in selective oxidation

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

It has been suggested that the activity and selectivity in catalytic oxidation of hydrocarbons over an oxide catalyst are related to the metal-oxygen bond strength. Sachtler proposed that selective catalysts have high rates of change of this bond energy with the degree of reduction of the oxide. Other correlations are found in the literature. We have measured the heat of oxidation of vanadium oxide supported on γ-Al2O3 as a function of the degree of reduction (DR) of the oxide by calorimetry. It was found that the heat increased rapidly as the degree of reduction increased, as did the rate of oxidation. However, the rate of reduction of the oxide was only a weak function of DR. When the catalytic properties of these samples in butane oxidation were tested using the pulse method, it was found that the selectivity changed rapidly with DR: the higher DR is, the higher is the selectivity for dehydrogenation. The selectivity also depended on the loading of vanadium oxide on the support. The sample of a higher loading was less selective and produced oxygenated as well as dehydrogenation products and carbon oxides. The sample of a lower loading produced only dehydrogenation products and carbon oxides. This difference in product selectivity was also observed in the steady state reaction. These results will be discussed with respect to the metal-oxygen bond strength and the nature of the vanadia species in the samples.

Original languageEnglish
Title of host publicationAmerican Chemical Society, Division of Petroleum Chemistry, Preprints
PublisherPubl by ACS
Pages986
Number of pages1
Volume37
Edition3
Publication statusPublished - Apr 1992
EventSymposium on Developing the Understanding of Heterogeneous Catalyst Systems presented at the 203rd National Meeting of the American Chemical Society - San Francisco, CA, USA
Duration: Apr 5 1992Apr 10 1992

Other

OtherSymposium on Developing the Understanding of Heterogeneous Catalyst Systems presented at the 203rd National Meeting of the American Chemical Society
CitySan Francisco, CA, USA
Period4/5/924/10/92

Fingerprint

Oxidation
Oxides
Oxygen
Metals
Dehydrogenation
Bond strength (chemical)
Vanadium
Catalysts
Carbon
Catalytic oxidation
Butane
Calorimetry
Hydrocarbons
Hot Temperature

ASJC Scopus subject areas

  • Fuel Technology

Cite this

Kung, H. H. (1992). Metal-oxygen bond strength of oxides and their catalytic properties in selective oxidation. In American Chemical Society, Division of Petroleum Chemistry, Preprints (3 ed., Vol. 37, pp. 986). Publ by ACS.

Metal-oxygen bond strength of oxides and their catalytic properties in selective oxidation. / Kung, Harold H.

American Chemical Society, Division of Petroleum Chemistry, Preprints. Vol. 37 3. ed. Publ by ACS, 1992. p. 986.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Kung, HH 1992, Metal-oxygen bond strength of oxides and their catalytic properties in selective oxidation. in American Chemical Society, Division of Petroleum Chemistry, Preprints. 3 edn, vol. 37, Publ by ACS, pp. 986, Symposium on Developing the Understanding of Heterogeneous Catalyst Systems presented at the 203rd National Meeting of the American Chemical Society, San Francisco, CA, USA, 4/5/92.
Kung HH. Metal-oxygen bond strength of oxides and their catalytic properties in selective oxidation. In American Chemical Society, Division of Petroleum Chemistry, Preprints. 3 ed. Vol. 37. Publ by ACS. 1992. p. 986
Kung, Harold H. / Metal-oxygen bond strength of oxides and their catalytic properties in selective oxidation. American Chemical Society, Division of Petroleum Chemistry, Preprints. Vol. 37 3. ed. Publ by ACS, 1992. pp. 986
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