Removal of sulfamethazine using peracetic acid activated by Fe0 and UV: Efficiency and mechanism study

Abstract

Peracetic acid (PAA) was successfully activated by UV and Fe0 to degrade sulfamethazine (SMT) in this study. UV/Fe0/PAA system not only could enhance SMT removal efficiency but also could reduce the energy consumption in comparison with UV, Fe0/PAA and UV/PAA systems. The RO• radical was the main radical for the degradation of SMT in UV/Fe0/PAA system and photolysis, •OH and R-O• exhibited 15.6%, 17.6% and 66.8% contribution for SMT degradation, respectively. Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscope (SEM), and X-ray photoelectron spectroscopy (XPS) were conducted to investigate the characterization of Fe0 after reaction in UV/Fe0/PAA system. The possible SMT degradation pathway was also proposed. Affecting factors such as Fe0 dosage (0–0.2 g L−1), PAA concentration (0–200 μM) and initial pH (3–9) were also studied. Cl−, NO3-, SO42- and HCO3- had a negligible adverse effect on SMT removal in this system indicating the good adaptability to inorganic ions. In addition, UV/Fe0/PAA system had the good recycle ability of Fe0 and showed a good performance in removing antibiotic in the nature fresh water. Therefore, this study notably improved the knowledge of PAA activated by Fe0 and UV and showed the potential applicability of UV/Fe0/PAA system in degrading antibiotics in nature fresh water.