Characterization of NH3 Fe catalytic systems by laser Raman spectroscopy

Hong bin Zhang, G. L. Schrader

Research output: Contribution to journalArticle

17 Scopus citations

Abstract

Laser Raman spectra of species adsorbed on doubly promoted fused iron catalysts were obtained under static and flowing atmospheres of NH3 and 1N2 3H2. The spectra provided new information about the nature of the surface species involved in iron-hydrogen, iron-nitrogen, and nitrogen-nitrogen bonding. Assignment of the Raman bands included: 1951 and 1902 cm-1 for the FeH stretch due to H(a); 1940 and 2040 cm-1 for the NN stretch due to N2(a); 1090 cm-1 for the FeN stretch due to N(a); 895 cm-1 for the FeN stretch due to NH(a); 500 cm-1 for the FeN stretch due to NH2(a); 465 and 410 cm-1 for the FeN stretch due to N2(a); and 140 cm-1 for the FeN stretch due to NH3(a). In situ studies and studies performed at room temperature indicated that dehydrogenation of NH3(a) to NH(a) or N(a) did not occur extensively for catalysts which had been reduced by H2 or for catalysts which were actually functioning for NH3 decomposition. N2(a) and H(a) were the dominant chemisorbed species on the surface of the functioning catalyst. The Raman results were consistent with an associative mechanism for ammonia synthesis or decomposition: {A figure is presented}.

Original languageEnglish (US)
Pages (from-to)461-471
Number of pages11
JournalJournal of Catalysis
Volume99
Issue number2
DOIs
StatePublished - Jun 1986

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'Characterization of NH<sub>3</sub> Fe catalytic systems by laser Raman spectroscopy'. Together they form a unique fingerprint.

  • Cite this