Evidence of new Ni-O-K catalytic sites with superior stability for methane dry reforming

Liquid fuels produced via Fischer-Tropsch synthesis from biomass-derived syngas constitute an attractive and sustainable energy vector for the transportation sector. This study focuses on the role of potassium as a promoter in Ni-based catalysts for reducing coke deposition during catalytic dry refo...

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Detalles Bibliográficos
Autores: Azancot, Lola, Blay, Vincent, Blay-Roger, Rubén, Bobadilla, Luis F., Penkova, Anna, Centeno, Miguel Ángel, Odriozola, José Antonio
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2022
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/358875
Acceso en línea:http://hdl.handle.net/10261/358875
https://api.elsevier.com/content/abstract/scopus_id/85123824228
Access Level:acceso abierto
Palabra clave:Catalytic stability
Heterogeneous catalysis
Methane dry reforming
Ni-O-K catalytic sites
Syngas
http://vocabularies.unesco.org/thesaurus/concept640
Descripción
Sumario:Liquid fuels produced via Fischer-Tropsch synthesis from biomass-derived syngas constitute an attractive and sustainable energy vector for the transportation sector. This study focuses on the role of potassium as a promoter in Ni-based catalysts for reducing coke deposition during catalytic dry reforming. The study provides a new structural link between catalytic performance and physicochemical properties. We identify new Ni-O-K chemical states associated with high stability in the reforming process, evidenced by different characterization techniques. The nickel particles form a core surrounded by a Ni-O-K phase layer (Ni@Ni-O-K) during the reduction of the catalyst. This phase likely presents an alkali-nickelate-type structure, in which nickel is stabilized in oxidation state + 3. The Ni-O-K formation induces essential changes in the electronic, physical, structural, and morphological properties of the catalysts, notably enhancing their long-term stability in dry reforming. This work thus provides new directions for designing more efficient catalysts for sustainable gas-to-liquids processes.