Isotopic apportioning of hydrogen/deuterium on the surface of an activated Iron carbide catalyst

Wilson D. Shafer, Venkat Ramana Rao Pendyala, Muthu Kumaran Gnanamani, Gary Jacobs, John P. Selegue, Shelley D. Hopps, Gerald A. Thomas, Burtron H. Davis

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


Fischer-Tropsch (FT) synthesis continues to receive widespread attention. Even after 90 years of investigation, the mechanistic route has yet to be fully defined. FT, as a polymerization process, uses CO and H2 as the reactants to produce a broad spectrum of hydrocarbons. Since the conception of the FT synthesis, several different isotopic routes have been employed for mechanistic studies. Various isotopes, such as 13C, 14C, 18O, and 2H, have been utilized through different types of experiments to shed light on the active site(s), the rate-limiting step, and the catalytic pathways. Direct evidence in the FT mechanism has been uncovered by utilizing experiments such as H2/D2 switching trials, as these experiments attempt to shed light on the rate-limiting step of CO hydrogenation. However, before hydrogen participates in the mechanism of CO hydrogenation, it may first dissociatively adsorb on the catalyst surface. The aim of this work is to ascertain to what extent H and D partition on the surface. This is accomplished by passing an equimolar H/D gas mixture over the activated FT catalyst, followed by a TPD method to determine if the active carbide surface displays a partitioning preference toward one of the isotopes. If a preference is observed, then the interpretation of kinetic isotopic effect (KIE) data ascertained in the CO hydrogenation switching experiments could potentially be affected. However, only a very slight isotopic preference toward deuterium was observed, and it is deemed not significant enough to affect an interpretation of the KIE based on H/D switching.

Original languageEnglish
Pages (from-to)1683-1690
Number of pages8
JournalCatalysis Letters
Issue number9
StatePublished - Sep 2015

Bibliographical note

Publisher Copyright:
© Springer Science+Business Media New York 2015.


  • Deuterium
  • Fischer-tropsch synthesis
  • Hydrogen
  • Iron carbide
  • Isotopic partitioning

ASJC Scopus subject areas

  • Catalysis
  • Chemistry (all)


Dive into the research topics of 'Isotopic apportioning of hydrogen/deuterium on the surface of an activated Iron carbide catalyst'. Together they form a unique fingerprint.

Cite this