Determination of the dispersion of supported Pt particles by gas-phase and liquid-phase measurements

Date

2009-02-15

Author

Kivrak, Hilal
Mastalir, Agnes
Kiraly, Zoltan
Üner, Deniz

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The dispersion of a Pt/gamma-Al2O3 catalyst was investigated by various experimental techniques. The values obtained by gas-phase hydrogen and carbon monoxide adsorption and transmission electron microscopy (TEM) were consistent for the metal:adsorbate stoichiometry of 1:1. However, these methods overestimated the number of active sites available for a liquid-phase reaction. For the hydrogenation of styrene in the presence Of CS2 as a catalyst poison, only the defect sites were found to be active in the catalytic reaction. The defect sites were related to the initial coverage dependent region of the adsorption heats measured by gas-phase microcalorimetry.

Subject Keywords

Process Chemistry and Technology, General Chemistry, Catalysis

URI

https://hdl.handle.net/11511/47484

Journal

CATALYSIS COMMUNICATIONS

DOI

https://doi.org/10.1016/j.catcom.2008.12.049

Collections

Department of Chemical Engineering, Article

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Citation Formats

H. Kivrak, A. Mastalir, Z. Kiraly, and D. Üner, “Determination of the dispersion of supported Pt particles by gas-phase and liquid-phase measurements,” CATALYSIS COMMUNICATIONS, pp. 1002–1005, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47484.