Electrochemical oxidation of Naproxen in aqueous matrices: Elucidating the intermediates’ eco-toxicity, by assessing its degradation pathways via experimental and density functional theory (DFT) approaches

The removal of the non-steroidal anti-inflammatory drug (NSAID) Naproxen (NAX) in water by hydroxyl radicals (•OH) was performed electrochemical advanced oxidation processes either with Pt or BDD anodes and a 3D carbon felt cathode. degradation NAX (•OH vs electrolysis time) well fitted to pseudo-first-order reaction rate kinetic. detected intermediates (aromatic compounds carboxylic acids) were experimentally monitored during process via LC, while density functional theory (DFT) applied uncover undetected intermediates, some for first time literature. formation toxic higher toxicity than identified, such as IMS4b (6-Methoxy-1-[1-(6-methoxynaphthalen-2-yl) ethyl] naphthalen-2-ol), catechol, glycolic acid. Based on these data, detailed pathway •OH proposed. evolution solution indicated that formed subsequently removed TOC process. Finally, almost complete mineralization achieved simulated urine wastewater electro-Fenton treatment, an optimized dose iron catalyst, showing EAOPs’ potential efficiently remove even from challenging matrices. In extension, strategies developed can be treatment other NSAIDs.