Plasma assisted dry reforming of methane: Syngas and hydrocarbons formation mechanisms

Plasma reactions of CO2 + CH4 mixtures have been proposed as a suitable process for the dry reforming of methane. Without specific catalysts, most studies report the formation of CO and H2 as main reaction products and arise the question whether CHx radicals coming from CH4 may interact with interme...

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Detalles Bibliográficos
Autores: Navascués, Paula, Cotrino Bautista, José, González-Elipe, Agustín R., Gómez Ramírez, Ana María
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/146741
Acceso en línea:https://hdl.handle.net/11441/146741
https://doi.org/10.1016/j.fuproc.2023.107827
Access Level:acceso abierto
Palabra clave:Methane dry reforming
Hydrogen production
Packed-bed plasma reactor
Isotope labeling
Plasma-catalysis
Plasma-assisted processes
Descripción
Sumario:Plasma reactions of CO2 + CH4 mixtures have been proposed as a suitable process for the dry reforming of methane. Without specific catalysts, most studies report the formation of CO and H2 as main reaction products and arise the question whether CHx radicals coming from CH4 may interact with intermediate species formed by electron impact dissociation of CO2, a critical step for the formation of high added value oxygenated compounds. We have addressed this question studying the CO2 + CH4 plasma reaction in a ferroelectric-moderated packedbed reactor varying the reactants ratio. Analysis of the reaction products by mass spectrometry and the plasma reaction intermediates by optical emission spectroscopy suggest that few direct cross-link interactions exist between intermediate plasma species issued from CH4 or CO2. This preliminary evidence is corroborated by experiments using 13CO2 instead 12CO2 as reactant. The isotope labeling procedure has proved that plasma reaction mechanisms of CO2 and CH4 molecules proceed almost independently, with the formation of small amounts of water and the removal of carbon deposits resulting CH4 plasma decomposition as sole evidences of cross reactions. These results highlight the need of using catalysts to promote specific surface reactions for a better control of the selectivity of the process.