Application of the electro-Fenton process to mesotrione aqueous solutions: Kinetics, degradation pathways, mineralization and evolution of the toxicity

Macedonian Journal of Chemistry and Chemical Engineering

Snezhana Efremova Aaron¹  Zoran Zdravkovski²  Jasmina Petreska Stanoeva²  Jean-Jacques Aaron³  Mehmet A. Oturan⁴  Minir Murati⁴  Nihal Oturan⁴ 

[1] Department of Medical Biochemistry, Medical Faculty, Ss. Cyril & Metodius University, 50 Divizija 6, 1000 Skopje;Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Ss. Cyril & Methodius University, Skopje;Paris-Est Marne-la-Vallee University, Paris;Université Paris-Est, Laboratoire Géomatériaux et Environnement (LGE), EA 4508, 5 Boulevard Descartes, 77454 Marne-La-Vallée;

关键词: mesotrione;    electro-fenton;    bdd, hydroxyl radicals;    degradation mechanism;    mineralization;    toxicity;   

DOI  :  10.20450/mjcce.2014.407

来源: DOAJ

【 摘 要 】

The kinetics and the mechanism of degradation of the mesotrione herbicide by three electrochemical advanced oxidation processes (EAOPs) systems, namely electro-Fenton (EF) with Pt anode (EF-Pt), anodic oxidation with BDD anode (AO) and EF-boron doped diamond anode (EF-BDD), were investigated in acidic aqueous solutions. The degradation of mesotrione obeyed apparent first-order reaction kinetics, and its absolute rate constant value with hydroxyl radicals at pH 3.0, determined by the competitive kinetics method, was found to be 8.20 × 108 L mol–1 s–1. Fourteen different mesotrione degradation products were separated and/or identified using HPLC / MSn analyses. A rationalized scheme was proposed for the reaction pathways of mesotrione degradation in the EF process. The mesotrione mineralization yield values ranged between about 58 and 97% for a 6-h electrolysis time, according to the type of EAOP system and the electrolysis current intensity value. The evolution of the toxicity of mesotrione aqueous solutions with electrolysis time (t) was investigated during treatment by the EF-Pt and EF-BDD systems. Toxicity was measured with the Microtox® method, based on the luminescence inhibition of marine bacteria Vibrio fischeri. The curves % inhibition vs. time were found to depend on the toxicity of formed mesotrione degradation products.

【 授权许可】

Unknown