Electrocatalytic dechlorination of 2,4-dichlorophenol in bioelectrochemical systems

In this work, the cathodic electro-dechlorination of 2,4-DCP in a Microbial Fuel Cell (MFC) was studied. To do that, an MFC externally connected with a 120 Ω load was operated by feeding a synthetic wastewater with 300 ppm of 2,4-DCP to the abiotic cathode compartment and sodium acetate to the bioti...

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Detalles Bibliográficos
Autores: León Fernández, Luis Fernando, Rodrigo Rodrigo, Manuel Andrés, Villaseñor Camacho, José, Fernández Morales, Francisco Jesús
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/29343
Acceso en línea:https://doi.org/10.1016/j.jelechem.2020.114731
http://hdl.handle.net/10578/29343
Access Level:acceso abierto
Palabra clave:Bioelectrochemical system
Microbial fuel cell
Organochlorines
2,4-Dichlorophenol
Dechlorination
Electro-reductive dehalogenation
Descripción
Sumario:In this work, the cathodic electro-dechlorination of 2,4-DCP in a Microbial Fuel Cell (MFC) was studied. To do that, an MFC externally connected with a 120 Ω load was operated by feeding a synthetic wastewater with 300 ppm of 2,4-DCP to the abiotic cathode compartment and sodium acetate to the biotic anode with electroactive bacteria. During the experiments, all the intermediates (2-chlorophenol and 4-chlorophenol) and final products (phenol and Cl−) from the dechlorination of 2,4-DCP were monitored. Results show that the bio-assisted electroreductive treatment achieved a cathodic dechlorination yield of a 57% after 24 h, which increases up to 88% after 72 h. In addition, because of the dechlorination of 2,4-DCP, the biodegradability of the synthetic wastewater, expressed as the ratio BOD/COD, was increased from negative values (corresponding to toxic effluents) up to 0.568. Meanwhile, the toxicity decreased drastically, with EC50 values that increased from 0.021 to 0.228 mmol L−1. Operation current densities during the bio-assisted electro-dehalogenation process were significant and decreased from initial values of 0.14 down to 0.04 mA cm−2. These results indicate that the bioelectrochemical technology can produce small amounts of energy while dechlorinating an extremely hazardous waste.