Efficient removal of metronidazole by ball milling synthesized graphite-doped pyrite activation of persulfate

This study details the synthesis of graphite-doped pyrite (FeS 2 bm /graphite) via ball milling and its application in the degradation of metronidazole (MNZ) using sodium persulfate (PS) as an oxidizing agent. The synthesized material was thoroughly characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis, which revealed a reduced particle size and an enhanced specific surface area compared to the original pyrite. These modifications significantly boost its adsorption capacity and catalytic efficiency for pollutant degradation. The study systematically investigates the effects of material dosage, PS concentration, and pH on degradation performance, identifying optimal conditions that resulted in a remarkable MNZ removal efficiency of over 99.7 %. Electron paramagnetic resonance (EPR) spectroscopy further confirmed the generation of reactive oxygen species (ROS), primarily hydroxyl and superoxide radicals, which played a key role in the degradation process. The findings underscore the high catalytic potential of FeS 2 bm /graphite in treating antibiotic-contaminated water and offer valuable insights for advancing oxidation processes in environmental remediation. • Metronidazole was effectively removed by the activation of sodium persulfate by FeS 2 bm /graphite. • •OH and O 2 •− are the main reactive oxygen species. • FeS 2 bm /graphite is simple to prepare and raw materials are readily available.