Hydrogenation of CO on supported Rh catalysts

F. Solymosi, I. Tombácz, M. Kocsis

Research output: Contribution to journalArticle

201 Citations (Scopus)

Abstract

The hydrogenation of CO on supported Rh was investigated in a flow technique. Special attention was focused on the identification of surface species formed during the reaction. The reaction occurred at measurable rate above 473 K. The product distribution sensitively depended on the support; while on Rh SiO2 mainly CH4 was formed, on Rh TiO2 a number of C2C5 compounds were also produced. In situ infrared spectroscopic measurements showed that only the linearly bonded CO exists with a detectable concentration on the surface during the reaction. It appeared, however, at lower frequencies than that corresponding to the RhCO species. In addition, the absorption bands characteristic for the formate ion and CHx compounds were also identified. The formation of surface C was also detected. Its amount increased during the conditioning period and also with temperature elevation. The specific rate of CH4 formation on Rh TiO2 was more than one order of magnitude higher than that of the less effective Rh MgO and Rh SiO2 catalysts. From the behaviors of surface formate under different conditions it was inferred that it does not play an important role in hydrocarbon synthesis on Rh catalysts. It is proposed that the important steps in CH4 formation are the dissociation of CO promoted by adsorbed hydrogen and the subsequent hydrogenation of surface carbon. As regards the high activity of Rh TiO2 it is assumed that an electronic interaction operates between the TiO2 and Rh influencing the bonding and reactivity of chemisorbed species.

Original languageEnglish
Pages (from-to)78-93
Number of pages16
JournalJournal of Catalysis
Volume75
Issue number1
DOIs
Publication statusPublished - 1982

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Carbon Monoxide
Catalyst supports
formic acid
Hydrogenation
hydrogenation
catalysts
formates
Catalysts
conditioning
Hydrocarbons
Absorption spectra
Hydrogen
Carbon
reactivity
hydrocarbons
dissociation
Ions
low frequencies
Infrared radiation
absorption spectra

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Hydrogenation of CO on supported Rh catalysts. / Solymosi, F.; Tombácz, I.; Kocsis, M.

In: Journal of Catalysis, Vol. 75, No. 1, 1982, p. 78-93.

Research output: Contribution to journalArticle

Solymosi, F. ; Tombácz, I. ; Kocsis, M. / Hydrogenation of CO on supported Rh catalysts. In: Journal of Catalysis. 1982 ; Vol. 75, No. 1. pp. 78-93.
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