Abstract
Peracetic acid (PAA) based advanced oxidation processes are increasingly used as alternative strategies for sulfonamide antibiotics (SAs) degradation. In this study, molybdenum (Mo) species were successfully anchored on the FeS2 surface. This catalyst (Mo-FeS2) could be used as an excellent PAA activator for the removal of sulfamethazine (SMT). Electrochemical measurements revealed that anchored Mo species lowered the electron transfer resistance on the FeS2 surface, and density functional theory (DFT) calculation suggested more electrons can be shifted from FeS2 to Mo, which is prone to transfer electrons for PAA activation. After 30 min reaction, 87.6 % of SMT could be removed by Mo-FeS2/PAA at pH 4, and reactive species (RSs) including HO•, CH3COO• and Fe(IV) were responsible for the SMT degradation. Increasing the dosages of PAA (0.02 – 0.5 mM) or Mo-FeS2 (0.1 – 0.4 g/L) facilitated the SMT degradation. DFT calculation results suggest that the aniline ring of SMT is vulnerable to attack induced by RSs. The degradation pathways of SMT, including Smiles rearrangements, hydroxylation of aniline ring, oxidation of the –NH2 group and coupling reaction, were proposed according to the identified oxidation products. Sulfamethoxazole, sulfadiazine, sulfanilamide and sulfathiazole could also be degraded by Mo-FeS2/PAA (>50 %), suggesting that the Mo-FeS2/PAA would be a competitive strategy for the remediation of SAs-contaminated water.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.