title: Solar photo-Fenton using peroxymonosulfate for organic micropollutants removal from domestic wastewater: comparison with heterogeneous TiO₂ photocatalysis.
abstract: This work aims at decontaminating biologically treated domestic wastewater effluents from organic micropollutants by sulfate radical based (SO4(-)) homogeneous photo-Fenton involving peroxymonosulfate as an oxidant, ferrous iron (Fe(II)) as a catalyst and simulated solar irradiation as a light source. This oxidative system was evaluated by using several probe compounds belonging to pesticides (bifenthrin, mesotrione and clothianidin) and pharmaceuticals (diclofenac, sulfamethoxazole and carbamazepine) classes and its kinetic efficiency was compared to that to the well known UV-Vis/TiO2 heterogeneous photocatalysis. Except for carbamazepine, apparent kinetic rate constants were always 10 times higher in PMS/Fe(II)/UV-Vis than in TiO2/UV-Vis system and more than 70% of total organic carbon abatement was reached in less than one hour treatment. Hydroxyl radical (OH) and SO4(-) reactivity was investigated using mesotrione as a probe compound through by-products identification by liquid chromatography-high resolution-mass spectrometry and transformation pathways elucidation. In addition to two OH based transformation pathways, a specific SO4(-) transformation pathway which first involved degradation through one electron transfer oxidation processes followed by decarboxylation were probably responsible for mesotrione degradation kinetic improvement upon UV-Vis/PMS/Fe(II) system in comparison to UVVis/TiO2 system.
authors.affiliation: UMR HydroSciences 5569, Montpellier Université, 15 Avenue Ch. Flahault, 34093 Montpellier cedex 5, France. Electronic address: moussa.mahdi@chemist.com.
authors.forename: Moussa Mahdi
authors.initials: MM
authors.lastname: Ahmed
authors.affiliation: PROMES-CNRS, UPR 8521, Tecnosud, Rambla de la Thermodynamique, 66100 Perpignan, France.
authors.forename: Monica
authors.initials: M
authors.lastname: Brienza
authors.affiliation: PROMES-CNRS, UPR 8521, Tecnosud, Rambla de la Thermodynamique, 66100 Perpignan, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Goetz
authors.affiliation: UMR HydroSciences 5569, Montpellier Université, 15 Avenue Ch. Flahault, 34093 Montpellier cedex 5, France.
authors.forename: Serge
authors.initials: S
authors.lastname: Chiron
mesh_terms: D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry*; D010575:Pesticides / Q000737:chemistry; D004364:Pharmaceutical Preparations / Q000737:chemistry; D010782:Photolysis; D013431:Sulfates / Q000737:chemistry; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: C045076:Fenton's reagent; D010545:Peroxides; D010575:Pesticides; D004364:Pharmaceutical Preparations; D013431:Sulfates; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; C038288:peroxymonosulfate; D006861:Hydrogen Peroxide; D014025:Titanium; D007501:Iron
keywords: Mesotrione; Solar photo-Fenton; Sulfate radical; Transformation pathways; Wastewater