Catalysis Letters

, Volume 38, Issue 1–2, pp 95–99

Molybdenum based catalysts. I. MoO2 as the active species in the reforming of hydrocarbons

  • A. Katrib
  • P. Leflaive
  • L. Hilaire
  • G. Maire
Article

Abstract

The XPS spectra of bulk MoO2 and MoO3 are reported. Commercial MoO2 reveals the presence of multilayers of MoO3 covering bulk MoO2. In situ reduction of bulk MoO3 by H2 at temperatures equal to 623 K and less than 673 K reduces the superficial layer(s) to mainly MoO2. Such phase is characterised by a certain density of states in terms of the free 4d, 5s electrons localised mainly on the Mo atoms and observed in the valence band energy region at the Fermi-level in the XP spectrum of this system. Catalytic reactions on the MoO2 phase of 2-methylpentane at atmospheric pressure using a mixture of the hydrocarbon (5 Torr) with hydrogen (755 Torr) yield 3-methylpentane andn-hexane as the main products in roughly equal amounts. These results are interpreted in terms of dual sites on the MoO2 surface.

Keywords

molybdenum dioxide XPS argon ion bombardment reforming of alkanes 

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Copyright information

© J.C. Baltzer AG, Science Publishers 1996

Authors and Affiliations

  • A. Katrib
    • 1
  • P. Leflaive
    • 1
  • L. Hilaire
    • 1
  • G. Maire
    • 1
  1. 1.LERCSI-URA 1498 CNRS-ULP-EHICSStrasbourg CedexFrance

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