Catalysis Letters

, Volume 26, Issue 1–2, pp 101–107 | Cite as

Emission of excited potassium species from an industrial iron catalyst for ammonia synthesis

  • Klas Engvall
  • Andrzej Kotarba
  • Leif Holmlid


The angular dependence of potassium emission-desorption is studied from a fused iron catalyst of the type used for ammonia synthesis. The excited species (K*, K n * , etc.) and positive ions K+ have strongly different angular distributions. The bilobular distribution measured for ion desorption is concluded to be either due to excited atoms, so-called Rydberg atoms, or excited clusters. Both types of species have to desorb from the edges of the sample and become field ionized and deexcited just outside the sample, as reported in previous studies on an iron oxide catalyst. The peak in the normal direction measured for excited species is due to excited cluster formation outside the catalyst surface. Similarities with previous results for other catalysts are observed. The possibility that the promoter function of potassium in the ammonia synthesis is due to excited species is pointed out.


angular dependence potassium emission-desorption fused iron catalyst ammonia synthesis 


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Copyright information

© J.C. Baltzer AG, Science Publishers 1994

Authors and Affiliations

  • Klas Engvall
    • 1
    • 2
  • Andrzej Kotarba
    • 1
    • 2
  • Leif Holmlid
    • 1
    • 2
  1. 1.Reaction Dynamics Group, Department of Physical ChemistryUniversity of GöteborgSweden
  2. 2.Chalmers University of TechnologyGothenburgSweden

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