Degradation of 4-aminoantipyrine by elecro-oxidation with a boron-doped diamond anode: optimization by central composite design, oxidation products and toxicity
| Autor: | Fábio Gozzi, Enric Brillas, Lucas de Melo da Silva, Amilcar Machulek Junior, Sílvio C. de Oliveira, Ignasi Sirés |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Environmental Engineering
Central composite design 02 engineering and technology 010501 environmental sciences engineering.material 01 natural sciences law.invention chemistry.chemical_compound law Environmental Chemistry Sulfate Waste Management and Disposal 0105 earth and related environmental sciences Electrolysis Depuració d'aigües residuals Aqueous solution Purification of sewage Diamond Oxidació electroquímica Mineralization (soil science) 021001 nanoscience & nanotechnology Pollution Anode Electrolytic oxidation chemistry engineering Degradation (geology) 0210 nano-technology Nuclear chemistry |
| Zdroj: | Dipòsit Digital de la UB Universidad de Barcelona |
| Popis: | 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. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|