Enhanced degradation of enoxacin using ferrihydrite-catalyzed heterogeneous photo-Fenton process

• Published in: Environmental research 2024-06, Vol.251 (Pt 1), p.118650, Article 118650
• Main Authors: Tian, Lin, Wang, Liting, Wei, Shikun, Zhang, Liwen, Dong, Deming, Guo, Zhiyong
• Format: Article
• Language: English
• Subjects: Antibiotic; Ferrihydrite; Fluoroquinolone; Heterogeneous photo-Fenton; Hydroxyl radical
• ISSN: 0013-9351; 1096-0953; 1096-0953
• DOI: 10.1016/j.envres.2024.118650

The ferrihydrite-catalyzed heterogeneous photo-Fenton reaction shows great potential for environmental remediation of fluoroquinolone (FQs) antibiotics. The degradation of enoxacin, a model of FQ antibiotics, was studied by a batch experiment and theoretical calculation. The results revealed that the degradation efficiency of enoxacin reached 89.7% at pH 3. The hydroxyl radical (∙OH) had a significant impact on the degradation process, with a cumulative concentration of 43.9 μmol L−1 at pH 3. Photogenerated holes and electrons participated in the generation of ∙OH. Eleven degradation products of enoxacin were identified, with the main degradation pathways being defluorination, quinolone ring and piperazine ring cleavage and oxidation. These findings indicate that the ferrihydrite-catalyzed photo-Fenton process is a valid way for treating water contaminated with FQ antibiotics. [Display omitted] •The degradation of enoxacin was the same under acidic and alkaline conditions.•Photogenerated electrons and holes participated in the formation of ∙OH.•All the products undergo hydroxylation.•Most transformation products were less toxic than the parent enoxacin.