Abstract
This focused review article underscores how metal reduction promoters can impact deactivation phenomena associated with cobalt Fischer-Tropsch synthesis catalysts. Promoters can exacerbate sintering if the additional cobalt metal clusters, formed as a result of the promoting effect, are in close proximity at the nanoscale to other cobalt particles on the surface. Recent efforts have shown that when promoters are used to facilitate the reduction of small crystallites with the aim of increasing surface Co0 site densities (e.g., in research catalysts), ultra-small crystallites (e.g., < 2–4.4 nm) formed are more susceptible to oxidation at high conversion relative to larger ones. The choice of promoter is important, as certain metals (e.g., Au) that promote cobalt oxide reduction can separate from cobalt during oxidation-reduction (regeneration) cycles. Finally, some elements have been identified to promote reduction but either poison the surface of Co0 (e.g., Cu), or produce excessive light gas selectivity (e.g., Cu and Pd, or Au at high loading). Computational studies indicate that certain promoters may inhibit polymeric C formation by hindering C-C coupling.
Document Type
Review
Publication Date
3-11-2014
Digital Object Identifier (DOI)
https://doi.org/10.3390/catal4010049
Funding Information
The authors would like to acknowledge the support of the Commonwealth of Kentucky.
Repository Citation
Jacobs, Gary; Ma, Wenping; and Davis, Burtron H., "Influence of Reduction Promoters on Stability of Cobalt/γ-Alumina Fischer-Tropsch Synthesis Catalysts" (2014). Center for Applied Energy Research Faculty and Staff Publications. 9.
https://uknowledge.uky.edu/caer_facpub/9
Notes/Citation Information
Published in Catalysts, v. 4, issue 1, p. 49-76.
© 2014 by the authors; licensee MDPI, Basel, Switzerland.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/).