Cephalexin removal by persulfate activation using simulated sunlight and ferrous ions

Autor: Carlos M. García Perdomo, Paula A. Ramírez Minota, Henry Zúñiga-Benítez, Gustavo A. Peñuela
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Water Science and Technology, Vol 85, Iss 1, Pp 52-62 (2022)
Druh dokumentu: article
ISSN: 0273-1223
1996-9732
DOI: 10.2166/wst.2021.509
Popis: This study presents the main results related to the use of activated persulfate (PS) in the elimination of the beta-lactam antibiotic cephalexin (CPX). Experiments were done using K2S2O8 and simulated sunlight. A face-centered central composite experimental design was used to analyze the effects of the solution pH and the PS concentration on the reaction, and to determine the optimized conditions that favor the CPX elimination. The results indicated that the removal of CPX is promoted by an acidic pH and under the higher evaluated PS dose (7.5 mg L−1). CPX total removal was achieved in 30 min. The analysis of the effect of the pollutant initial concentration indicated that a pseudo-first-order kinetics model can be used to describe the reaction. Likewise, the use of Fe2+ ions for PS activation (in the dark) was evaluated and established that a higher concentration of ions favors the pollutant removal. Control tests and under the presence of scavenger agents indicated that both HO• and SO4−• radicals would be present in the solution and promote the CPX elimination. The assessment of the solution dissolved organic carbon, nitrates and sulfates was also carried out, and indicated that a portion of the organic matter was mineralized. HIGHLIGHTS Antibiotic cephalexin was eliminate using persulfate and simulated sunlight.; Antibiotic total elimination was achieved in 30 min.; Ferrous ions can activate persulfate and promote cephalexin removal in water.; HO• and SO4−• radicals would be present in the solution.; Part of the organic matter was mineralized.;
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