title: A novel heterogeneous system for sulfate radical generation through sulfite activation on a CoFe2O4nanocatalyst surface.
abstract: Heterogeneous catalytic activation is important for potential application of new sulfate-radical-based advanced oxidation process using sulfite as source of sulfate radical. We report herein a heterogeneous system for sulfite activation by CoFe2O4nanocatalyst for metoprolol removal. Factors that influence metoprolol removal were investigated, including pH and initial concentrations of components. The CoFe2O4nanocatalyst was characterized by X-ray diffractometry (XRD) and transmission electron microscopy (TEM), and the catalytic stability was tested by consecutive runs. Radicals generated in the CoFe2O4S(IV)O2system were identified through radical quenching experiments and by electron spin resonance (ESR). The catalytic mechanism was elucidated further by X-ray photoelectron spectroscopy (XPS). The catalytic process was dependent on initial pH, and more than 80% of the metoprolol can be removed at pH 10.0 following the Langmubir-Hinshelwood equation. The generation of Co-OH complexes on the CoFe2O4surface was crucial for sulfite activation. SO4-was verified to be the main oxidative species responsible for metoprolol degradation. Other organic pollutants, such as sulfanilamide, sulfasalazine, 2-nitroaniline, sulfapyridine, aniline, azo dye X-3B and 4-chloroaniline, could also be removed in this CoFe2O4S(IV)O2system. The results suggest that the CoFe2O4S(IV)O2system has good application prospects in alkaline organic wastewater treatment.
authors.affiliation: School of Civil Engineering, Wuhan University, Wuhan, 430072, China.
authors.forename: Zizheng
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China.
authors.forename: Shaojie
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Xu
authors.affiliation: Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China.
authors.forename: Yifan
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China. Electronic address: ljj0410@163.com.
authors.forename: Jinjun
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China. Electronic address: fengwu@whu.edu.cn.
authors.forename: Feng
authors.initials: F
authors.lastname: Wu
keywords: Alkaline pH; CoFe(2)O(4) nanocatalyst; Metoprolol; Oxysulfur radical; Sulfite