Efficient degradation of sulfamethoxazole by NiCo2O4 modified expanded graphite activated peroxymonosulfate: Characterization, mechanism and degradation intermediates

Mengjuan Xu; Hongyu Zhou; Zelin Wu; Naiwen Li; Zhaokun Xiong; Gang Yao; Bo Lai

doi:10.1016/j.jhazmat.2020.123103

Efficient degradation of sulfamethoxazole by NiCo₂O₄ modified expanded graphite activated peroxymonosulfate: Characterization, mechanism and degradation intermediates

J Hazard Mater. 2020 Nov 15:399:123103. doi: 10.1016/j.jhazmat.2020.123103. Epub 2020 Jun 5.

Authors

Mengjuan Xu¹, Hongyu Zhou¹, Zelin Wu¹, Naiwen Li², Zhaokun Xiong¹, Gang Yao³, Bo Lai⁴

Affiliations

¹ State Key Laboratory of Hydraulics and Mountain River Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China; Sino-German Centre for Water and Health Research, Sichuan University, Chengdu 610065, China.
² State Key Laboratory of Hydraulics and Mountain River Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Hydraulic and Hydroelectric Engineering, Sichuan University, Chengdu 610065, China. Electronic address: linaiwen@scu.edu.cn.
³ Sino-German Centre for Water and Health Research, Sichuan University, Chengdu 610065, China; Institute of Environmental Engineering, RWTH Aachen University, Germany.
⁴ State Key Laboratory of Hydraulics and Mountain River Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China; Sino-German Centre for Water and Health Research, Sichuan University, Chengdu 610065, China. Electronic address: laibo@scu.edu.cn.

PMID: 32937720
DOI: 10.1016/j.jhazmat.2020.123103

Abstract

Expanded graphite (EG) immobilized nickel ferrite (NiCo₂O₄) was successfully constructed by a simple hydrothermal approach and applied for the degradation of sulfamethoxazole (SMX) in model wastewater by peroxymonosulfate (PMS) activation. The features of prepared catalysts were characterized by SEM, TEM, EDS, XRD, BET, TPD and XPS techniques. The influences of several critical parameters including the prepared NiCo₂O₄-EG dosages, PMS concentrations, temperature, initial solution pH and inorganic ions on SMX removal were studied in details. In particular, the synthesized NiCo₂O₄-EG exhibits excellent catalytic performances for SMX depredation over a wide pH range (pH 3.0-11.0). Besides, the transformation of various reactive oxygen species (SO₄^-, HO, O₂^- and ¹O₂) with the change of initial pH was investigated by the electron paramagnetic resonance (EPR) and quenching tests. In addition, twelve major degradation intermediates of SMX were detected by UPLC-QTOF-MS/MS. Finally, the PMS activation mechanism in NiCo₂O₄-EG/PMS system by the synergistic coupling of EG and NiCo₂O₄ were put forward. In brief, this work provided a promising and potential catalyst for PMS activation to remove SMX from wastewater.

Keywords: Degradation intermediates; NiCo(2)O(4) modified EG; Peroxymonosulfate; Reactive oxygen species; Sulfamethoxazole.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Graphite*
Peroxides
Sulfamethoxazole
Tandem Mass Spectrometry
Water Pollutants, Chemical* / analysis

Substances

Peroxides
Water Pollutants, Chemical
peroxymonosulfate
Graphite
Sulfamethoxazole