Efficient removal of levofloxacin by FeCo2O4@C-REC activated peroxymonosulfate: Performance and mechanism

The advanced oxidation process based on peroxymonosulfate (PMS) has obvious advantages in treating antibiotic wastewater, but finding a green, economical and feasible catalyst still be a key for its large-scale application. In this research, a rectorite-based metal material (FeCo 2 O 4 @C-REC) was synthesized by the sol-gel method, and its catalytic performance and mechanism were estimated by levofloxacin (LVX, a typical antibiotic substance) removal through activating PMS. A more than 80 % LVX removal efficiency can achieve in 10 min under the conditions of pH 6.8, catalyst dosage 0.4 g/L and PMS concentration 0.4 g/L. Liquid chromatography-mass spectrometer (LC-MS) and ECOSAR analysis showed 10 intermediates appeared in LVX degradation process, and the intermediates pose a minimal harm to the ecosystem. Quenching experiments and Electron Paramagnetic Resonance (EPR) analysis found OH and SO 4 − were the main reactive oxygen species (ROS) for LVX degradation. The redox between a large number of hydroxyl groups Co (iii)/Co (ii) and Fe (iii)/Fe (ii) on REC surface played an important role for activating PMS to produce ROS. Different water matrices experiments, cycle experiments, and metal ion leaching tests demonstrated FeCo 2 O 4 @C-REC had a good applicability and stability for activating PMS to degrade LVX. Our study may provide a new sight for catalyst large-scale application to remove antibiotic wastewater though PMS activation.