Electrochemical incineration of glyphosate wastewater using three-dimensional electrode

• Published in: Environmental technology Vol. 42; no. 2; pp. 170 - 181
• Main Authors: Oliveira, Kaíque S. G. C., Farinos, Rosimeire M., Veroli, Alyne B., Ruotolo, Luís A. M.
• Format: Journal Article
• Language: English; French
• Published: England Taylor & Francis 2021; Taylor & Francis Ltd
• Subjects: Anodes; Anodic oxidation; Anodizing; Box-Behnken design; Current efficiency; Electrochemistry; Electrode materials; Electrodes; Energy consumption; Factorial design; Flow rates; Flow velocity; Glycine - analogs & derivatives; Glyphosate; Incineration; Lead oxides; Mass transfer; Mass transport; Mineralization; Organic compounds; Oxidation; Oxidation-Reduction; Performance degradation; Porous media; Wastewater; Wastewater treatment; Water Pollutants, Chemical - analysis; Anodic oxidation; Box–Behnken design; mass transfer; wastewater treatment; glyphosate
• ISSN: 0959-3330; 1479-487X
• DOI: 10.1080/09593330.2019.1625563

Anodic oxidation of recalcitrant organic compounds is still challenging concerning to the anode material and mass transport limitations imposed by the low concentration. In this work, we studied the degradation of a real wastewater containing glyphosate using an electrode of PbO 2 electrodeposited on a three-dimensional matrix of reticulated vitreous carbon (RVC). The high mass transfer rate provided by the RVC/PbO 2 anode is demonstrated. A Box-Behnken factorial design was used for a systematic analysis of the effects of current density, flow rate and temperature on the degradation and mineralisation kinetics, current efficiency and specific energy consumption. The optimised degradation performance was achieved applying 30 mA cm −2 , 3000 mL min −1 and 50°C. As the flow rate increases from 150 to 1500 mL min −1 , the current efficiency increases from 18% to 65% and the energy consumption dropped from 72 to 33 kWh kg −1 due to the mass transfer enhancement promoted by the porous matrix. The efficacy of the electrochemical process for the treatment of real effluents using the three-dimensional PbO 2 has been demonstrated.