Catalysis Letters

, Volume 14, Issue 3–4, pp 305–313 | Cite as

The role of C2 intermediates in Fischer-Tropsch synthesis over ruthenium

  • Kamala R. Krishna
  • Alexis T. Bell
Article

Abstract

The C2 products formed over Ru during Fischer-Tropsch synthesis often lie well below the Anderson-Schulz-Flory line describing the C4+ products. This has led to speculation that either the surface precursor to C2 hydrocarbons is exceptionally long lived, or that the ethylene formed by CO hydrogenation readsorbs and thereby reenters the chain growth process. In this study, the role of ethylene readsorption on the dynamics of chain initiation and growth is investigated using13CO/H2 and12C2H4 to differentiate between the carbon sources. Ethylene addition is found to suppress the rate of methanation and increase the rates of formation of C3+ hydrocarbons. Ethylene serves as an effective chain initiator, as well as a source of C1 monomer species which participate in chain propagation. No evidence is seen, though, for the participation of C2 species in chain propagation.

Keywords

C2 intermediates Fischer-Tropsch synthesis 

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Copyright information

© J.C. Baltzer A.G. Scientific Publishing Company 1992

Authors and Affiliations

  • Kamala R. Krishna
    • 1
  • Alexis T. Bell
    • 1
  1. 1.Chemical Sciences Division, Lawrence Berkeley Laboratory, and Department of Chemical EngineeringUniversity of CaliforniaBerkeleyUSA

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