Metal Dispersion and Alloy Homogeneity in Highly Dispersed Pt-Au/Al2O3 Catalysts

• Autorzy: Yurkiv V. , Legawiec-Jarzyna M. , Juszczyk W. , Kowalczyk Z. , Karpiński Z.
• Języki publikacji: EN

Abstrakty

EN

Although hydrogen chemisorption performed in a pulse-flow system allows for a reliable determination of platinum dispersion in Pt/Al2O3 catalysts, it fails in the case when platinum is alloyed with gold. Much weaker hydrogen adsorption on mixed Pt-Au sites is not detected by this method which measures only instantaneous irreversible chemisorption. On the other hand, the static chemisorption method givestrustworthy values of metal dispersion. So, a combination of these two methods (pulse-flow and static) probes effectively both the metal dispersion as well as the d gree of alloying in supported Pt-Au catalysts. Obtained characterization data for the series of Pt-Au/Al2O3 catalysts prepared by incipient wetness impregnaion suggest that in this case Pt and Au remain intimately mixed in the form of Pt–Au bimetallic particles.

Słowa kluczowe

EN

Pt/Al2O3 catalyst; Pt-Au/Al2O3 catalysts; pulse chemisorption of H2; static chemisorption of CO

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2008
• Tom: Vol. 82, nr 9
• Strony: 1711--1711
• Opis fizyczny: –1716, Bibliogr. 20 poz., rys.

Twórcy

autor

Yurkiv V.

autor

Legawiec-Jarzyna M.

autor

Juszczyk W.

autor

Kowalczyk Z.

autor

Karpiński Z.

• Institute of Physical Chemistry of PAS, ul. Kasprzaka 44/52, 01-224 Warszawa, Poland Fax: [phone],

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