Additional pathways for the ethanol electro-reforming knowledge: The role of the initial concentration on the product yields

Ethanol electrochemical reforming mechanism on bimetallic PtRu/C catalyst was studied in a proton exchange membrane cell at 80 °C. In this work, we report for the first time the ethyl acetate pathway in acid media, evaluating all the possible chemical routes that may be involved in the ethanol oxida...

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Detalles Bibliográficos
Autores: Rodríguez-Gómez, Alberto, Dorado Fernández, Fernando, Consuegra, Antonio de Lucas, Osa Puebla, Ana Raquel de la
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/29900
Acceso en línea:https://hdl.handle.net/10578/29900
Access Level:acceso abierto
Palabra clave:Electrochemical reforming
Reaction mechanism
PEM cell
Ethanol concentration
Hydrogen production
Product yields
Reformado electroquímico
Mecanismo de reacción
Celda PEM
Concentración de etanol
Producción de hidrógeno
Rendimientos del producto
Descripción
Sumario:Ethanol electrochemical reforming mechanism on bimetallic PtRu/C catalyst was studied in a proton exchange membrane cell at 80 °C. In this work, we report for the first time the ethyl acetate pathway in acid media, evaluating all the possible chemical routes that may be involved in the ethanol oxidation reaction. Chronopotentiometry and open circuit voltage essays were conducted for different reactant compositions to explore each pathway nature individually. Among all processes, only ethyl acetate follows a non-electrocatalytic mechanism (via hemiacetal) with the consequent over-faradaic hydrogen production. The influence of the initial concentration on the product yields was studied for a wide range of ethanol solutions (0.5–6 M) and applied current levels (0.2–1.4 A). Promising current density values were obtained (1000 mA cm−2, 1.4 V) for high ethanol concentrations (4–6 M), which led to high conversion rates. Additionally, losses in the electrocatalytic activity took place for 0.5–3 M solutions at potentials close to 1 V due to mass transfer limitations. Regarding product distribution (apart from H2), low concentration levels increased the acetic acid yield, while more concentrated solutions boosted the acetaldehyde and ethyl acetate generation. Finally, the required power to achieve 1 kg of each reaction product was estimated.