OXIDATIVE DESTRUCTION OF AMOXICILLIN IN PHOTO-FENTON-LIKE OXIDIZING SYSTEM USING SOLAR IRRADIATION

The kinetic regularities of oxidative destruction of β-lactam penicillin antibiotics are studied using amoxicillin as example in Fenton-like iron-persulfate system under solar irradiation. The effect of Fe2+ and persulfate concentrations on the antibiotic degradation rate and mineralization in terms of total organic carbon (TOC) decay in combined {Solar/Fe2+ /S2O82-} system was examined. With the increase of oxidant concentration from 0.5 mM to 1.5 mM, the initial reaction rate of amoxicillin degradation increased to 2.5-fold, and the conversion of target compound and TOC mineralization reached 90% and 19%, respectively, after 120 min of solar exposure. Increasing the Fe2+ concentration from 0.1 mM to 0.3 mM resulted in a 1.5-fold increase in the initial reaction rate of amoxicillin oxidation and up to 21% for TOC mineralization. A comparative evaluation of different oxidizing systems was given. It was experimentally established that the efficiency of amoxicillin destruction process increases in the order: {S2O82-} < {Solar} < {Solar/S2O82-} < {Fe2+/S2O82-} < < {Solar/Fe2+/S2O82-}. It should be noted that TOC mineralization was observed only in combined {Solar/Fe2+/S2O82-} system, which indicates to deep oxidation of intermediates and, consequently, increasing biodegradability of the final reaction products. It was found that in the real water matrix, in the natural surface water of Selenga River, inhibition of amoxicillin degradation and TOC mineralization were observed, due to a greater extent to bicarbonate ions presented in it. The obtained results demonstrate the prospect of using solar irradiation for effective degradation of β-lactam penicillin antibiotics in the combined {Solar/Fe2+/S2O82-} oxidation system. For citation: Alekseev K.D., Sizykh M.R., Batoeva A.A. Oxidative destruction of amoxicillin in photo-fenton-like oxidizing system using solar irradiation. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 12. P. 123-130. DOI: 10.6060/ivkkt.20246712.7082.