Details

Autor(en) / Beteiligte

• Ahmed, Moussa Mahdi
• Brienza, Monica
• Goetz, Vincent
• Chiron, Serge

Titel

Solar photo-Fenton using peroxymonosulfate for organic micropollutants removal from domestic wastewater: Comparison with heterogeneous TiO2 photocatalysis

Ist Teil von

• Chemosphere (Oxford), 2014-12, Vol.117, p.256-261

Ort / Verlag

Kidlington: Elsevier Ltd

Erscheinungsjahr

2014

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• •UV–Vis/PMS/Fe(II) was ten times faster than UV–Vis/TiO2 for pesticide and pharmaceutical removal.•Higher TOC abatement was obtained in UV–Vis/PMS/Fe(II) system.•Sulfate radical reactivity was responsible for mesotrione degradation kinetic enhancement.•A specific sulfate radical transformation route involved one electron oxidation reactions.•This selective and additional pathway accounted for enhanced mesotrione removal in wastewater. 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.