Degradation of herbicide S-metolachlor by electrochemical AOPs using a boron-doped diamond anode

The degradation and mineralization ability of electrochemical processes like electro-oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and UVA-assisted photoelectro-Fenton (PEF) has been comparatively studied for solutions of the herbicide S-metolachlor. Solutions of 100 mL have be...

Descripción completa

Detalles Bibliográficos
Autores: Guelfi, Diego Roberta de Vieira, Gozzi, Fábio, Machulek Jr., Amílcar, Sirés Sadornil, Ignacio, Brillas, Enric, De Oliveira, Silvio César
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2018
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/152898
Acceso en línea:https://hdl.handle.net/2445/152898
Access Level:acceso abierto
Palabra clave:Oxidació electroquímica
Depuració d'aigües residuals
Electrolytic oxidation
Purification of sewage
Descripción
Sumario:The degradation and mineralization ability of electrochemical processes like electro-oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and UVA-assisted photoelectro-Fenton (PEF) has been comparatively studied for solutions of the herbicide S-metolachlor. Solutions of 100 mL have been treated using an undivided cell equipped with an air-diffusion cathode and a boron-doped diamond (BDD) anode. The effect of pH, current density, and Fe2+ and S-metolachlor concentration has been thoroughly studied. The total organic carbon removal profiles have demonstrated the feasibility of almost overall mineralization by EF and PEF after 9 h at 300 mA. The herbicide decays in both treatments informed about the complexation of Fe(III) ions formed from Fenton's reaction, which decelerated S-metolachlor removal. However, the high oxidation power of BDD anode allowed the gradual mineralization of such complexes. The identification of chlorinated and non-chlorinated degradation byproducts by GC-MS has allowed the proposal of main degradation routes.