Metal-support interaction in Pt/Al/sub 2/O/sub 3/ catalysts

Journal Article · Thu Jun 15 04:00:00 EDT 1978 · J. Catal.; (United States)

OSTI ID:5714198

Den Otter, G J; Dautzenberg, F M

The ''inaccessible platinum'', which became undectable by hydrogen adsorption, X-ray diffraction, and electron spectroscopy after treating alumina-supported platinum in hydrogen above 500/sup 0/C was studied by hydrogen and oxygen adsorption and titration techniques, changes of selectivity in the hydrogen/n-hexane reaction, and NMR measurements of the Pt-Knight shift. Thermodynamic considerations, the decrease of hydrogen chemisorption, the constant oxygen titration stoichiometry, the change of Pt-Knight shift, and the increase in selectivity for n-hexane aromatization over cracking and isomerization on catalysts treated in hydrogen at 500/sup 0/-650/sup 0/C were consistent with formation of Pt-Al alloy. The consumed hydrogen in the titration of chemisorbed oxygen was higher than could be accounted for by the oxygen-covered platinum sites on high-temperature treated catalyst, which suggested that the alloy decomposed into platinum oxide and aluminum oxide during oxygen adsorption at 0/sup 0/C. Diagram, graphs, tables, and 21 references.

• Research Organization: Shell Res. B.V.
• OSTI ID: 5714198
• Journal Information: J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 53:1; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
ADSORPTION
ALKANES
ALLOYS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
AROMATIZATION
CATALYST SUPPORTS
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISORPTION
COHERENT SCATTERING
CRACKING
DECOMPOSITION
DIFFRACTION
ELECTRON SPECTROSCOPY
ELEMENTS
EVALUATION
HEXANE
HIGH TEMPERATURE
HYDROCARBONS
HYDROGEN
ISOMERIZATION
METALS
NMR SPECTRA
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PLATINUM
PLATINUM ALLOYS
PLATINUM METAL ALLOYS
PLATINUM METALS
PYROLYSIS
SCATTERING
SEPARATION PROCESSES
SORPTION
SPECTRA
SPECTROSCOPY
THERMOCHEMICAL PROCESSES
THERMODYNAMICS
TITRATION
TRANSITION ELEMENTS
X-RAY DIFFRACTION