Degradation of Sulfamethazine Antibiotics in Fenton-Like System Using Fe_3O_4 Magnetic Nanoparticles as Catalyst

摘要

In this study, Fe_3O_4 magnetic nanoparticles (MNPs) were synthesized, characterized and used for the degradation of sulfamethazine (SMT). The results showed that Fe_3O_4 MNPs were efficient and reusable heterogeneous catalytic for SMT degradation in a Fenton-like system. More than 80% of the SMT was degraded under optimal conditions: initial pH of 3.0, 20 mM ofH_2O_2, Fe_3O_4 MNPs dose of 1.0 g/L, and initial concentration of SMT 20 mg/L (initial total organic carbon: 10.4 mg/L). Among the parameters that affect SMT degradation, initial pH is of crucial importance to degrade SMT in the Fenton-like system. A possible pathway of SMT degradation was proposed based on detected products in the solution. The Fe_3O_4 MNPs exhibited high stability and reusability. The SMT removal remained at 80% over five runs with the catalyst. Slight agglomeration and dissolution of Fe_3O_4 MNPs after reactions were observed by X-ray diffraction and field emission scanning electron microscopy analysis. The SMT removal and mineralization could be enhanced using Fe_3O_4 MNPs/powder-activated carbon (PAC) composite as catalyst. The removal efficiency of SMT and TOC increased to 94.7% and 80.8% in optimal conditions, respectively, in Fenton-like system catalyzed by Fe_3O_4 MNPs/PAC composite.