Impact of topology framework of microporous solids on methanol carbonylation: An operando DRIFTS-MS study

Methanol carbonylation was evaluated over heterogeneous catalysts based on Cu-exchanged zeolitic materials with different topology: Cu@MOR, Cu@FER, and Cu@ZSM-5. Despite the similar Si/Al ratios, it is crucial to acknowledge that the acid strength is influenced by the framework topology, as supporte...

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Detalles Bibliográficos
Autores: Luque-Álvarez, L. A., Serrano-Cruz, M., González Castaño, M., Bobadilla, Luis F., Odriozola, José Antonio
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2023
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/355437
Acceso en línea:http://hdl.handle.net/10261/355437
https://api.elsevier.com/content/abstract/scopus_id/85164722497
Access Level:acceso abierto
Palabra clave:Heterogeneous catalysts
Methanol carbonylation
Operando DRIFTS-MS
Zeolites topology
http://vocabularies.unesco.org/thesaurus/concept640
Descripción
Sumario:Methanol carbonylation was evaluated over heterogeneous catalysts based on Cu-exchanged zeolitic materials with different topology: Cu@MOR, Cu@FER, and Cu@ZSM-5. Despite the similar Si/Al ratios, it is crucial to acknowledge that the acid strength is influenced by the framework topology, as supported by the NH3-TPD results. This, along with other characterization techniques allowed us to estimate the impact of pore size and pore distribution in these microporous materials on catalytic performance. The channel structure influenced catalytic parameters such as conversion and selectivity. The higher methanol conversion achieved on Cu@FER shows the importance of Brønsted acid sites and redox centres location regarding the topology of the material. Concerning the selectivity, the production of acetic acid was endorsed by the 12-MR (MOR) channels, methyl acetate's production by the 10-MR (FER) channels. Finally, the presence of 6-MR (ZSM-5) channels led to a complete selectivity towards DME production. The reaction mechanism was elucidated via operando DRIFTS-MS and results revealed a bifunctional mechanism in which methanol adsorbs and dehydrates on acidic Brønsted sites and CO is activated over Cu+ species.