Catalytic degradation of lomefloxacin by photo-assisted persulfate activation on natural hematite: Performance and mechanism

The natural hematite (α-Fe2O3) is stable and abundant on the earth, as well as with strange electronic band structure and good visible light absorption properties. However, the composition and catalytic performance of natural hematite should be explored. In this study, the photo-assisted hematite nanoparticles activated persulfate (H-NPs/PS/vis) system was constructed. As detected, H-NPs had an irregular agglomerate structure with abundant internal pore and were mainly composed of Fe2O3, SiO2 and TiO2. The system was applied to removing various antibiotic (i.e., lomefloxacin, ciprofloxacin and enrofloxacin with initial concentration of 10 mg/L), achieving high degradation performance of 82.0%, 81.2% and 82.2% after 120, 330 and 240 min, respectively. Moreover, H-NPs had excellent reusability with low metal leaching (Ti leaching percentage lower than 0.01%, Fe dissolution percentage was 0.48%) and stable structure. At last, a possible reaction mechanism of H-NPs/PS/vis system was proposed that lomefloxacin (LOM) was efficiently removed via the synergistic process of components contained in H-NPs with PS and light, involving the generation of •O2−, •OH and SO4•−. Above all, this paper provided a novel application scheme of natural hematite through in-depth and comprehensive experimental exploration. The photo-assisted hematite nanoparticles activated persulfate system was constructed and used to remove nonbiodegradable organic pollutants in water. A possible reaction mechanism of as-obtained system was proposed based on the analysis characterization and experimental results. [Display omitted]