Electro‐oxidation of amoxicillin using titanium electrodes electrophoretically coated by iridium or ruthenium with tantalum oxides
Itzel León, Helena I. Gomes, S. Sepúlveda-Guzmán, Jesús Cárdenas, Fernando F. Rivera, J. Manríquez, Erika Bustos
Abstract
Abstract BACKGROUND Amoxicillin (AMX) is one of the pharmaceutical compounds in waters being targeted in wastewater decontamination studies, and some of the technological alternatives to degrade it involve using modified surfaces with transition metal oxides, such as IrO 2 /Ta 2 O 5 |Ti and RuO 2 /Ta 2 O 5 |Ti, for in situ production of hydroxyl radical ( • OH) to oxidize AMX in aqueous media. RESULTS The IrO 2 /Ta 2 O 5 |Ti 70:30 electrode was best suited for AMX electro‐oxidation, with 99.23% removal measured by HPLC‐UV–Vis, 81.13% by COD removal, and current efficiency of 41.1% in 0.1 mol L –1 Na 2 SO 4 after applying 15 mA for 6 h. These results are due to a larger surface area (251.67 cm 2 ) and a higher amount of • OH radicals being generated by cm 2 in neutral pH (3.8 mol L –1 cm −2 ) compared to the other electrodes. CONCLUSION This paper shows the simulation of the experimental data regarding the complete degradation of AMX (100%) by HPLC, comparing the experimental results and simulation results for AMX degradation using the IrO 2 /Ta 2 O 5 |Ti 70:30. The modeling predicts and validates the disengagement of COD obtained experimentally, considering the mechanism proposed by Trovó and collaborators for the electro‐oxidation of AMX to product C6 (C 16 H 22 N 3 O 7 S) by generating • OH. © 2020 Society of Chemical Industry (SCI)