Comparison of different precious metals in activated carbon-supported catalysts for the gas-phase hydrodechlorination of chloromethanes

Four precious metals supported on activated carbon are compared as catalysts in the gas-phase hydrodechlorination (HDC) of chloromethanes. The intrinsic activity or turnover frequency (TOF) of the catalysts follows the order Pd/C > Rh/C > Pt/C > Ru/C in the HDC of dichloromethane (DCM) whil...

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Detalles Bibliográficos
Autores: Martin Martínez, María, Gómez Sainero, Luisa María, Álvarez Montero, Ariadna, Bedia García-Matamoros, Jorge, Rodríguez Jiménez, Juan José
Tipo de recurso: artículo
Fecha de publicación:2013
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/709445
Acceso en línea:http://hdl.handle.net/10486/709445
https://dx.doi.org/10.1016/j.apcatb.2012.11.041
Access Level:acceso abierto
Palabra clave:hydrodechlorination
residual gases
chloromethanes
carbon-supported metallic catalysts
reaction scheme
Física
Química
Descripción
Sumario:Four precious metals supported on activated carbon are compared as catalysts in the gas-phase hydrodechlorination (HDC) of chloromethanes. The intrinsic activity or turnover frequency (TOF) of the catalysts follows the order Pd/C > Rh/C > Pt/C > Ru/C in the HDC of dichloromethane (DCM) while the sequence Pd/C > Pt/C > Rh/C > Ru/C was found for the HDC of chloroform (TCM). High selectivities to non-chlorinated products were obtained in all cases except for the HDC of TCM with Rh/C and Ru/C where the selectivity to DCM greatly depends on the operating conditions. A wider diversity of non-chlorinated hydrocarbons was obtained as reaction products with these two catalysts, especially in the HDC of TCM, favoring the formation of carbonaceous deposits which provoked a marked deactivation of the catalysts. In contrast, CH4 was the only non-chlorinated product obtained with the Pt/C catalysts which showed by far the highest stability. Different reaction pathways were found depending on the catalyst and the starting chloromethane. The different reactivity of the metals is explained in terms of their different electronic structure and the physicochemical properties of the catalysts