Heterogeneous Fenton Degradation of Nalidixic Acid on Fe(II)‐Sorbed Maghemite, as Probed by In Situ Attenuated Total Reflectance‐Fourier Transform Infrared Spectroscopy

The degradation of nalidixic acid (NAL) via heterogeneous Fenton reactions is investigated using Fe(II)‐sorbed maghemite (Mh) as catalyst. The Fenton reaction is triggered by hydrogen peroxide (H 2 O 2 ) and in situ attenuated total reflectance‐Fourier transform infrared spectroscopy is employed to monitor the evolution of the NAL spectrum, providing insights into the degradation mechanisms at the molecular level. Key spectral changes are observed, indicating the formation of degradation products and suggesting a ring‐opening in the first degradation steps. The efficiency of the reactions is influenced by the surface loading of NAL and Fe(II) on the substrates. This work contributes to the understanding of advanced oxidation processes for antibiotic degradation relying on cost‐effective remediation techniques.