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Kinetics and Catalysis

, Volume 47, Issue 3, pp 389–394 | Cite as

Properties and deactivation of the active sites of an MoZSM-5 catalyst for methane dehydroaromatization: Electron microscopic and EPR studies

  • V. I. Zaikovskii
  • A. V. Vosmerikov
  • V. F. Anufrienko
  • L. L. Korobitsyna
  • E. G. Kodenev
  • G. V. Echevskii
  • N. T. Vasenin
  • S. P. Zhuravkov
  • E. V. Matus
  • Z. R. Ismagilov
  • V. N. Parmon
Article

Abstract

The MoZSM-5 (4.0 wt % Mo) catalyst has been characterized by high-resolution transmission electron microscopy, EDXA, and EPR. Two types of molybdenum-containing particles are stabilized in the catalyst in the course of nonoxidative methane conversion at 750°C. These are 2-to 10-nm molybdenum carbide particles on the zeolite surface and clusters smaller than 1 nm in zeolite channels. According to EPR data, these clusters contain the oxidized molybdenum form Mo5+. The surface Mo2C particles are deactivated at the early stages of the reaction because of graphite condensation on their surface. Methane is mainly activated on oxidized molybdenum clusters located in the open molecular pores of the zeolite. The catalyst is deactivated after the 420-min-long operation because of coke buildup on the zeolite surface and in the zeolite pores.

Keywords

Zeolite Methane Conversion Molybdenum Carbide Zeolite Surface Methane Decomposition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© MAIK “Nauka/Interperiodica” 2006

Authors and Affiliations

  • V. I. Zaikovskii
    • 1
  • A. V. Vosmerikov
    • 2
  • V. F. Anufrienko
    • 1
  • L. L. Korobitsyna
    • 2
  • E. G. Kodenev
    • 1
  • G. V. Echevskii
    • 1
  • N. T. Vasenin
    • 1
  • S. P. Zhuravkov
    • 3
  • E. V. Matus
    • 1
  • Z. R. Ismagilov
    • 1
  • V. N. Parmon
    • 1
  1. 1.Boreskov Institute of Catalysis, Siberian DivisionRussian Academy of SciencesNovosibirskRussia
  2. 2.Institute of Petroleum Chemistry, Siberian DivisionRussian Academy of SciencesTomskRussia
  3. 3.Institute of Strength Physics and Materials Science, Siberian DivisionRussian Academy of SciencesTomskRussia

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