Topics in Catalysis

, Volume 1, Issue 3–4, pp 195–214 | Cite as

On the structure of the activated iron catalyst for ammonia synthesis

  • J. Schütze
  • W. Mahdi
  • B. Herzog
  • R. Schlögl
Ammonia Synthesis

Abstract

The contribution focuses on a brief account of the activation of iron oxide precursors to ammonia synthesis catalysts and discusses the question as to why “normal iron” is so inferior in catalytic performance compared to “ammonia iron”. The combination of microstructural analysis with kinetic observations allows the conclusion that the microtexture of ammonia iron is with a platelet morphology different from isotropic iron. The role of all additives in the generation of the platelet form is examined. The presence of oxygen, which was speculated to be beneficial for the reaction under certain conditions, was found to be detrimental for the catalytic performance under the present testing conditions.

Keywords

ammonia synthesis micro structure X-ray diffraction promoters iron reduction 

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Copyright information

© J. C. Baltzer AG, Science Publishers 1994

Authors and Affiliations

  • J. Schütze
    • 1
  • W. Mahdi
    • 1
  • B. Herzog
    • 2
  • R. Schlögl
    • 2
  1. 1.Fritz Haber Institut der Max-Planck GesellschaftBerlinGermany
  2. 2.Department of Inorganic ChemistryUniversity of FrankfurtFrankfurtGermany

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