A DFT study of the chain growth probability in Fischer-Tropsch synthesis

Jun Cheng, P. Hu*, Peter Ellis, Sam French, Gordon Kelly, C. Martin Lok

*Corresponding author for this work

Research output: Contribution to journalArticle

72 Citations (Scopus)

Abstract

The chain growth probability (alpha value) is one of the most significant parameters in Fischer-Tropsch (FT) synthesis. To gain insight into the chain growth probability, we systematically studied the hydrogenation and C-C coupling reactions with different chain lengths on the stepped Co(0001) surface using density functional theory calculations. Our findings elucidate the relationship between the barriers of these elementary reactions and the chain length. Moreover, we derived a general expression of the chain growth probability and investigated the behavior of the alpha value observed experimentally. The high methane yield results from the lower chain growth rate for C-1 + C-1 coupling compared with the other coupling reactions. After C-1, the deviation of product distribution in FT synthesis from the Anderson-Schulz-Flory distribution is due to the chain length-dependent paraffin/olefin ratio. (C) 2008 Elsevier Inc. All rights reserved.

Original languageEnglish
Pages (from-to)221-228
Number of pages8
JournalJournal of Catalysis
Volume257
Issue number1
Early online date2 Jun 2008
DOIs
Publication statusPublished - 1 Jul 2008

Keywords

  • Fischer-Tropsch
  • DFF
  • CO
  • chain growth probability
  • C-C coupling
  • methane
  • density-functional theory
  • transition-metal surfaces
  • catalyzed hydrocarbon synthesis
  • alpha-olefin readsorption
  • CO oxidation
  • product distributions
  • rate coefficients
  • reaction pathways
  • cobalt catalysts
  • iron catalysts

Cite this

Cheng, J., Hu, P., Ellis, P., French, S., Kelly, G., & Lok, C. M. (2008). A DFT study of the chain growth probability in Fischer-Tropsch synthesis. Journal of Catalysis, 257(1), 221-228. https://doi.org/10.1016/j.jcat.2008.05.006