Elucidating deactivation of titania-supported cobalt Fischer-Tropsch catalysts under simulated high conversion conditions

Elucidating deactivation of titania-supported cobalt Fischer-Tropsch catalysts under simulated high conversion conditions

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

2023

The study of titania-supported cobalt nanoparticles is relevant for industrial Fischer-Tropsch synthesis (FTS). Herein, we report about various deactivation pathways of cobalt supported on P25 titania (cobalt loading 2–8 wt%) under simulated high conversion conditions using in situ Mössbauer spectroscopy. A fraction of metallic cobalt was oxidized under humid FTS conditions. The absolute amount of oxidized cobalt was ∼ 1.2 wt% independent of the cobalt loading, indicating that specific cobalt-titanol interactions are involved in the oxidation process. The formation of cobalt-titanate-like compounds was only observed under very high water-to-hydrogen ratios in the absence of carbon monoxide. Steam considerably enhances cobalt sintering under FTS conditions. As such, deactivation under humid FTS conditions is not only caused by cobalt oxidation but also by enhancing sintering of the active phase.

Cobalt
Deactivation
Fischer-Tropsch synthesis
Humidity
Mössbauer spectroscopy

http://resolver.tudelft.nl/uuid:1056e16a-6d76-4832-a845-db782fea6c37

https://doi.org/10.1016/j.jcat.2023.02.019

0021-9517

Journal of Catalysis, 420, 44-57

Institutional Repository

journal article

© 2023 L.M. van Koppen, A.I. Dugulan, G. Leendert Bezemer, Emiel J.M. Hensen