Deactivation behavior of Pd/C and Pt/C catalysts in the gas-phase hydrodechlorination of chloromethanes: Structure-reactivity relationship

This study analyzes the influence of chemical and physical properties of Pd/C and Pt/C hydrodechlorination (HDC) catalysts in the different evolution of their activity during time on stream. Pt/C showed stable activity in the HDC of dichloromethane (DCM) and chloroform (TCM), while Pd/C was deactiva...

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Detalles Bibliográficos
Autores: Martin-Martinez, M., Álvarez Montero, Ariadna, Gómez Sainero, Luisa María, Baker, R. T., Palomar Herrero, José Francisco, Omar, Salama, Eser, S., Rodríguez Jiménez, Juan José
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/675404
Acceso en línea:http://hdl.handle.net/10486/675404
https://dx.doi.org/10.1016/j.apcatb.2014.07.017
Access Level:acceso abierto
Palabra clave:Chloromethanes
Deactivation
Hydrodechlorination
Pd/C
Pt/C
Química
Descripción
Sumario:This study analyzes the influence of chemical and physical properties of Pd/C and Pt/C hydrodechlorination (HDC) catalysts in the different evolution of their activity during time on stream. Pt/C showed stable activity in the HDC of dichloromethane (DCM) and chloroform (TCM), while Pd/C was deactivated after 90h of operation, particularly during HDC of DCM. The deactivation of Pd/C catalyst can be attributed to the lower proportion of zero-valent species and larger metal particle size. This appears to hinder the H2 dissociation, enhance the irreversible chemisorption of reactants and reaction products, and favor coupling reactions (leading to the formation of carbonaceous deposits) and/or metal phase change reactions. The more extensive deactivation of Pd/C in the HDC of DCM is attributed to the stronger chemisorption of the reactant on the catalyst, which leads to the formation of a new PdCx phase by the incorporation of carbon atoms into the metal lattice