The mechanism of the Fischer-Tropsch reaction over supported cobalt catalysts

Márton Kollár, Adriana De Stefanis, Hanna E. Solt, Magdolna R. Mihályi, J. Valyon, Anthony A G Tomlinson

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Natural gas and coal are converted to fuels by the Fischer-Tropsch reaction, i.e., by reacting CO with H2, the currently accepted mechanism involving surface carbide formation. We have monitored the adsorbed species and their evolution during Fischer-Tropsch reaction on the commercial catalyst Pt,Co/γ-Al2O3 (as a standard), on Co/alumina-pillared montmorillonite (Co,Al-EFW) and its beidellite analogue (both are tri-octahedral smectite clays, but beidellite possesses tetrahedrally coordinated Al in the sheets) via optical diffuse reflectance (DRS1) and variable temperature in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS2). We show that in this case over Pt/Co-γ-Al2O3, under model conditions, H2 reacts with CO forming H-CO bridges over [Co-μO2-Co] units; this transition state moiety also involves adjacent matrix Al-O-CO units. Subsequent stages provide differing oxygenate species via concerted acid-base reactions. The early stages of the Fischer-Tropsch synthesis thus do not involve surface carbide species and surface oxygenates are generated via concerted reaction of support surface Al-OH with the above HCO-bridging binuclear Co2+ unit.

Original languageEnglish
Pages (from-to)37-45
Number of pages9
JournalJournal of Molecular Catalysis A: Chemical
Volume333
Issue number1-2
DOIs
Publication statusPublished - Dec 1 2010

Fingerprint

Carbon Monoxide
Cobalt
cobalt
catalysts
Catalysts
montmorillonite
carbides
Carbides
Bentonite
reflectance
Fischer-Tropsch synthesis
Aluminum Oxide
Coal
natural gas
Clay minerals
coal
clays
Fourier transform infrared spectroscopy
Natural gas
Clay

Keywords

  • 15%Co,0.5%Pt/γ-alumina
  • Co -alumina-pillared clays
  • Fischer-Tropsch mechanism
  • Operando DRIFTS

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry
  • Process Chemistry and Technology

Cite this

The mechanism of the Fischer-Tropsch reaction over supported cobalt catalysts. / Kollár, Márton; De Stefanis, Adriana; Solt, Hanna E.; Mihályi, Magdolna R.; Valyon, J.; Tomlinson, Anthony A G.

In: Journal of Molecular Catalysis A: Chemical, Vol. 333, No. 1-2, 01.12.2010, p. 37-45.

Research output: Contribution to journalArticle

Kollár, Márton ; De Stefanis, Adriana ; Solt, Hanna E. ; Mihályi, Magdolna R. ; Valyon, J. ; Tomlinson, Anthony A G. / The mechanism of the Fischer-Tropsch reaction over supported cobalt catalysts. In: Journal of Molecular Catalysis A: Chemical. 2010 ; Vol. 333, No. 1-2. pp. 37-45.
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