2026-04-17T19:17:53Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1528152025-12-04T20:56:29Zcom_2072_1057col_2072_478796col_2072_478917

00925njm 22002777a 4500 dc Da Silva, Lucas de Melo author Gozzi, Fábio author Sirés Sadornil, Ignacio author Brillas, Enric author De Oliveira, Silvio César author Machulek Jr., Amílcar author 2020-03-17T11:54:25Z 2020-03-17T11:54:25Z 2018-03-16 2020-03-17T11:54:25Z Electro-oxidation with electrogenerated H2O2 (EO-H2O2) was applied to treat acidic aqueous solutions of 4-aminoantipyrine (4-AA), a persistent drug metabolite of dipyrone, in sulfate medium. Trials were made using a boron-doped diamond anode in the presence of H2O2 electrogenerated on site. A 24 central composite design (CCD) was employed to evaluate the effect of four independent variables, namely current density (j), pH, 4-AA concentration and electrolysis time, on the percentages of degradation and mineralization, as well as on mineralization current efficiency (MCE). Predicted responses agreed with observed values, showing linear trendlines with good R2 and R2adj values. The degradation was optimum at j = 77.5 mA cm-2, pH 3.5 and 62.5 mg L-1 4-AA, leading to 63% and 99% removal after 3 and 7 min, respectively. For those solutions, the largest mineralization was found at j = 77.5 mA cm-2, attaining 45% abatement at 175 min. Low MCE values were obtained in all electrolyses. An initial route for 4-AA degradation is proposed based on one dimer and eleven aromatic and aliphatic intermediates detected in the treated solutions at pH 3.5 by LC-MS. The initial 62.5 mg L-1 solution at pH 3.5 presented acute toxicity on Artemia salina larvae, with LC50 = 13.6 mg L-1, being substantially reduced after 3 and 7 min of EO-H2O2 at j = 77.5 mA cm-2 due to the formation of less toxic derivatives. Oxidació electroquímica Depuració d'aigües residuals Electrolytic oxidation Purification of sewage Degradation of 4-aminoantipyrine by elecro-oxidation with a boron-doped diamond anode: optimization by central composite design, oxidation products and toxicity