Peroxymonosulfate Activation by Fe@N Co-Doped Biochar for the Degradation of Sulfamethoxazole: The Key Role of Pyrrolic N

• Published in: International journal of molecular sciences Vol. 25; no. 19; p. 10528
• Main Authors: Liu, Tong, Li, Chenxuan, Chen, Xing, Chen, Yihan, Cui, Kangping, Wang, Dejin, Wei, Qiang
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.10.2024; MDPI
• Subjects: Activation energy; Adsorption; biochar; Carbon; Catalysis; Catalytic oxidation; Charcoal - chemistry; Decomposition; Efficiency; Electron Spin Resonance Spectroscopy; Fourier transforms; Gastroenteritis; Iron - chemistry; Liu, Timothy; Metronidazole; Nanoparticles; Nitrogen - chemistry; Peroxides - chemistry; peroxymonosulfate; Pollutants; pyrrolic N; Reactive Oxygen Species - chemistry; Spectrum analysis; Sulfamethoxazole; Sulfamethoxazole - chemistry; sulfate radicals; Technology application; Tetracycline; Tetracyclines; Water Pollutants, Chemical - chemistry; sulfate radicals; biochar; pyrrolic N; peroxymonosulfate
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms251910528

In this study, Fe, N co-doped biochar (Fe@N co-doped BC) was synthesized by the carbonization-pyrolysis method and used as a carbocatalyst to activate peroxymonosulfate (PMS) for sulfamethoxazole (SMX) removal. In the Fe@N co-doped BC/PMS system, the degradation efficiency of SMX (10.0 mg·L ) was 90.2% within 40 min under optimal conditions. Radical quenching experiments and electron spin resonance (ESR) analysis suggested that sulfate radicals (SO ), hydroxyl radicals ( OH), and singlet oxygen ( O ) participated in the degradation process. After the reaction, the proportion of pyrrolic N decreased from 57.9% to 27.1%. Pyrrolic N served as an active site to break the inert carbon network structure and promote the generation of reactive oxygen species (ROS). In addition, pyrrolic N showed a stronger interaction with PMS and significantly reduced the activation energy required for the reaction (∆G = 23.54 kcal/mol). The utilization potentiality of Fe@N co-doped BC was systematically evaluated in terms of its reusability and selectivity to organics. Finally, the intermediates of SMX were also detected.