Selective oxidation of hydrocarbons on supported Au catalysts

Neema A. Mashayekhi, Mayfair C. Kung, Harold H Kung

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

The importance of proximity of isolated TiOx cluster to Au surface for the formation of acetone in the selective oxidation of propane was investigated using a model system of Au particles decorated with mononuclear TiOx units dispersed in silica clusters. The results showed that no acetone was formed without TiOx, and its formation was more prominent on a sample containing a higher density of TiOx. Covering a Au/TiO2 catalyst with a layer of TiOx-containing silica changed the product selectivity from predominently propene to acetone. The data strongly supported the importance of isolated TiOx clusters near the Au surface in acetone formation, and suggested the relevance of Au-TiOx interface sites. Such interface sites might also be important in selective propene epoxidation that was coupled to CO oxidation in a H2O-methanol mixture. Using oxygen isotope labeling technique, it was found that the proximal source of oxygen in propene oxide was not from H2O but from O2. The observation was consistent with a methyl hydroperoxide intermediate, which could be formed by oxidation of a Ti methoxy at the Au-support interface.

Original languageEnglish
Pages (from-to)74-79
Number of pages6
JournalCatalysis Today
Volume238
DOIs
Publication statusPublished - 2014

Fingerprint

Hydrocarbons
Acetone
Catalyst supports
Propylene
Oxidation
Silicon Dioxide
Oxygen Isotopes
Silica
Propane
Oxygen
Epoxidation
Carbon Monoxide
Labeling
Hydrogen Peroxide
Isotopes
Methanol
Catalysts
Oxides
propylene

Keywords

  • Catalyst
  • Epoxidation
  • Gold
  • Interfacial site
  • Oxidation
  • Propane

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

Cite this

Selective oxidation of hydrocarbons on supported Au catalysts. / Mashayekhi, Neema A.; Kung, Mayfair C.; Kung, Harold H.

In: Catalysis Today, Vol. 238, 2014, p. 74-79.

Research output: Contribution to journalArticle

Mashayekhi, Neema A. ; Kung, Mayfair C. ; Kung, Harold H. / Selective oxidation of hydrocarbons on supported Au catalysts. In: Catalysis Today. 2014 ; Vol. 238. pp. 74-79.
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