Nitrogen doped magnetic porous carbon derived from starch of oatmeal for efficient activation peroxymonosulfate to degradation sulfadiazine

Abstract

Nitrogen doped magnetic porous carbon catalyst based on starch of oatmeal was obtained by mixing and pyrolysis process, and its catalytic activity of peroxymonosulfate activation for sulfadiazine degradation was evaluated. When ratio of oatmeal/urea/iron was 1: 2: 0.1, CN@Fe-10 had the best catalytic activity to degrade sulfadiazine. Around 97.8 % removal of 20 mg L−1 sulfadiazine was achieved under incorporating of 0.05 g L−1 catalyst and 0.20 g L−1 peroxymonosulfate. Good adaptability, stability and universality of CN@Fe-10 were verified under different conditions. Electron paramagnetic resonance and radical quenching test suggested that surface-bound reactive oxides species and singlet oxygen were the main reactive oxides species in this reaction. Electrochemical analysis indicated that CN@Fe-10 had a good electrical conductivity and electron transferred did occur among CN@Fe-10 surface, peroxymonosulfate and sulfadiazine. X-ray photoelectron spectroscopy suggested that Fe0, Fe3C, pyridine nitrogen and graphite nitrogen were the potential active sites for peroxymonosulfate activation. Therefore, the work provided a practical approach for recycling biomass.