Removal of amoxicillin employing Fenton-type process using delaminated clay and layered double hydroxides impregnated with Fe or Cu as catalysts

Abstract

The presence of antibiotics in the environment has raised concerns due to their potential negative effects on ecosystems. Conventional water treatment methods are ineffective at removing antibiotics. This study aims to investigate the efficiency of Fenton-like processes catalyzed by delaminated clay and layered double hydroxides impregnated with Fe or Cu for the degradation of amoxicillin. The catalysts were obtained by synthesizing delaminated clay and layered double hydroxides and subsequently impregnating them with Fe or Cu. The characterization of catalysts involved X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray fluorescence (XRF), N2 adsorption-desorption, and X-ray photoelectron spectroscopy (XPS). Catalytic activity was assessed by varying the concentration of hydrogen peroxide, the initial concentration of amoxicillin, and the amount of catalyst. The determination of byproducts was done by high-performance liquid chromatography (HPLC) with a quadrupole time-of-flight mass spectrometer (QqTof). The study found that layered double hydroxides impregnated with Fe or Cu were able to remove 100% of amoxicillin in just 20 min. The study identified 16 byproducts, indicating a degradation process. Under all of the studied conditions, the copper catalysts showed the highest percentage of amoxicillin removal.