Sintering and carbidization under simulated high conversion on a cobalt-based Fischer-Tropsch catalyst; manganese oxide as a structural promotor

Sintering and carbidization under simulated high conversion on a cobalt-based Fischer-Tropsch catalyst; manganese oxide as a structural promotor

van Koppen, L.M. (TU Delft RST/Fundamental Aspects of Materials and Energy; Eindhoven University of Technology)
Dugulan, A.I. (TU Delft RID/TS/Instrumenten groep)
Hensen, Emiel J.M.
Bezemer, G. Leendert (Shell Global Solutions International B.V.)

2022

The commercial application of cobalt-based Fischer-Tropsch synthesis (FTS) suffers from catalyst deactivation. One of the main deactivation mechanisms under industrial conditions is sintering. In this work, we explored the role of manganese oxide as a structural promoter against sintering in a carbon nanofiber supported cobalt model catalyst. We employed in situ Mössbauer emission spectroscopy to study cobalt sintering in synthesis gas as a function of the steam partial pressure, which mimics high CO conversion during FTS. Steam accelerates the sintering of non-promoted metallic cobalt particles. Model experiments point to a synergistic effect between carbon monoxide and steam on cobalt sintering. In the mangense-promoted case, sintering is significantly reduced, indicative of the structural stabilization of small cobalt particles by manganese oxide. Nevertheless, a fraction of cobalt particles in close interaction with manganese oxide carburized under these conditions, resulting in a lower catalytic activity.

Cobalt
Deactivation
Fischer-Tropsch synthesis
Manganese oxide
Mössbauer spectroscopy

http://resolver.tudelft.nl/uuid:ef283185-7b90-4816-9722-c4c658577477

https://doi.org/10.1016/j.jcat.2022.06.020

0021-9517

Journal of Catalysis, 413, 106-118

Institutional Repository

journal article

© 2022 L.M. van Koppen, A.I. Dugulan, Emiel J.M. Hensen, G. Leendert Bezemer