Treatment of toluene gaseous streams using packed column electro-scrubbers and cobalt mediators

An absorption system has been combined with an electrochemical cell to treat a gaseous stream polluted with toluene. Toluene retention in 3 h operation tests was higher than 87.0% in the case of treating the gaseous stream with single scrubbing, 97.0% in the case of using electro-scrubbing and over...

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Detalhes bibliográficos
Autores: Escalona Durán, Florymar, Muñoz Morales, Martín, Freitas-Araújo, Karla Caroline de, Sáez Jiménez, Cristina, Cañizares Cañizares, Pablo, Martínez Huitle, Carlos Alberto, Rodrigo Rodrigo, Manuel Andrés
Formato: artículo
Fecha de publicación:2021
País:España
Recursos:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/29252
Acesso em linha:https://hdl.handle.net/10578/29252
Access Level:acceso abierto
Palavra-chave:Ingeniería Química
Electroabsorción
Corriente de aire contaminada
Tolueno
Eliminación de COV
Mediadores metálicos
Descrição
Resumo:An absorption system has been combined with an electrochemical cell to treat a gaseous stream polluted with toluene. Toluene retention in 3 h operation tests was higher than 87.0% in the case of treating the gaseous stream with single scrubbing, 97.0% in the case of using electro-scrubbing and over 99.0% in using cobalt-mediated electro-scrubbing. It was found that the amount of toluene that escapes from the electro-scrubber does not only depend on the flow rate but also on the current density and the presence of the metallic mediator. The higher the current densities are, the higher the amount of electrochemically degraded toluene is. In addition to the mediating effect of the metal catalyst, the results also suggest an important participation of the redox sulfate/persulfate pair in the degradation of toluene. Only methyl-cyclohexane (at very low concentrations) is observed as intermediate, despite carboxylic acids were also initially expected. The formation of this compound can be explained in terms of the hydrogenation of toluene. The very low concentrations absorbed, and the very high current densities, support the occurrence of an electrochemical cold combustion in the electro-scrubber.