Enhanced degradation of levofloxacin hydrochloride synergistically with hydroxylamine hydrochloride via Fe3O4-loaded Medulla Tetrapanacis residue in a Fenton-like process

In this study, a straightforward strategy was introduced to enhance the reduction of Fe 3+ ions, thereby enabling the efficient degradation of levofloxacin hydrochloride (LEV), which effectively addresses the limitations associated with conventional Fenton-like reactions. A novel Fe 3 O 4 @MMT catalyst was successfully synthesized using Medulla Tetrapanacis residue and was employed in Fenton-like reactions, with hydroxylamine hydrochloride (HAHC) serving synergistically as a reducing agent. Under optimal experimental conditions, the degradation efficiency of LEV reached 97.20 % within 120 min. In comparison with the Fe 3 O 4 @MMT/H 2 O 2 system and the Fe 3 O 4 @MMT/HAHC arrangement, the Fe 3 O 4 @MMT/H 2 O 2 /HAHC system exhibited a significantly enhanced degradation efficiency of LEV, reaching an impressive 96.11 % degradation from nearly 30 % within a span of merely 120 min. Moreover, the system demonstrated excellent degradation performance across a wide pH range of 3–11 and remained effective under various anionic conditions, including Cl − , NO 3 − , HCO 3 − , SO 4 2− , and humic acid. The system exhibited notable stability and reusability; after five consecutive cycles, the degradation rate of LEV remained at 89.03 %, with a total iron leaching concentration of only 0.56 mg·L −1 . Quenching experiments and EPR analyses confirmed that hydroxyl (•OH) radicals played a dominant role in the degradation process of LEV. Based on LC-MS identification of degradation intermediates, five plausible decomposition pathways for LEV were proposed and validated through toxicity evaluation tests (TEST), revealing that most of the 16 identified intermediates exhibited reduced toxicity. This study provides an innovative approach and theoretical foundation for the efficient removal of LEV from wastewater using the simply way. • A novel Fe 3 O 4 @MMT synthesized using Medulla Tetrapanacis residue. • Efficient degradation of levofloxacin hydrochloride (LEV) in the Fe 3 O 4 @MMT system through the addition of hydroxylamine hydrochloride. • The reduced toxicity risk of 16 identified intermediates after LEV degradation.