UV-assisted nitrogen-doped reduced graphene oxide/Fe₃O₄ composite activated peroxodisulfate degradation of norfloxacin

ABSTRACT

We reported the preparation of NGO-Fe₃O₄ by simple hydrothermal-co-precipitation. The catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). It was demonstrated that norfloxacin (NOR) could be effectively degraded by the UV/NGO-Fe₃O₄/PDS system. The degradation efficiency reached 100% within 13 min (the concentration of NOR and ${\mathrm{S}}_2{\mathrm{O}}_8^{2-}$ were 100 mg L⁻¹ and 1 mM, respectively; m(NGO-Fe₃O₄): m(PDS) = 4: 1; pH: 3.0). In addition, NGO-Fe₃O₄ showed stable catalytic activity in recycling. The analysis found that the in-situ generated ·OH was the main active free radicals but ${\mathrm{SO}}_4^{-}\cdot$ also participated in the NOR degradation. Based on the identified intermediates, the NOR degradation pathways were proposed with UV/NGO-Fe₃O₄/PDS system.

GRAPHICAL ABSTRACT

KEYWORDS:

• UV
• NGO-Fe₃O₄
• peroxodisulfate
• norfloxacin. degradation kinetics

Acknowledgements

The authors acknowledge Henan Provincial Department of Science and Technology Research Project. (172102310562).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Henan Provincial Department of Science and Technology [grant number 172102310562].