Efficient activation of peroxymonosulfate by magnetic Mn-MGO for degradation of bisphenol A

Jiangkun Du; Jianguo Bao; Ying Liu; Haibo Ling; Han Zheng; Sang Hoon Kim; Dionysios D Dionysiou

doi:10.1016/j.jhazmat.2016.08.021

Efficient activation of peroxymonosulfate by magnetic Mn-MGO for degradation of bisphenol A

J Hazard Mater. 2016 Dec 15:320:150-159. doi: 10.1016/j.jhazmat.2016.08.021. Epub 2016 Aug 8.

Authors

Jiangkun Du¹, Jianguo Bao², Ying Liu¹, Haibo Ling¹, Han Zheng¹, Sang Hoon Kim³, Dionysios D Dionysiou⁴

Affiliations

¹ School of Environmental Studies, China University of Geosciences, Wuhan 430074, P.R. China.
² School of Environmental Studies, China University of Geosciences, Wuhan 430074, P.R. China. Electronic address: bjianguo@cug.edu.cn.
³ Center for Materials Architecturing, Korea Institute of Science and Technology, Seoul, 136-791, Republic of Korea. Electronic address: kim_sh@kist.re.kr.
⁴ Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering, 705 Engineering Research Center, University of Cincinnati, Cincinnati, OH 45221-0012, United States. Electronic address: dionysios.d.dionysiou@uc.edu.

PMID: 27544727
DOI: 10.1016/j.jhazmat.2016.08.021

Abstract

A heterogeneous manganese/magnetite/graphene oxide (Mn-MGO) hybrid catalyst was fabricated through the reduction of KMnO₄ by ethylene glycol in the presence of magnetite/GO (MGO) particles. The Mn-MGO catalyst exhibited high efficacy and long-term stability in activating peroxymonosulfate (PMS) to generate sulfate radicals for the removal of bisphenol A (BPA) from water. The results of the batch experiments indicated that an increase in the catalyst dose and solution pH could enhance BPA degradation in the coupled Mn-MGO/PMS system. Regardless of the initial pH, the solution pH significantly dropped after the reaction, which was caused by catalytic PMS activation. The production of sulfate radicals and hydroxyl radicals was validated through radical quenching and electron paramagnetic resonances (EPR) tests. BPA degradation pathways were proposed on the basis of LC-MS and GC-MS analyses. Finally, a possible mechanism of catalytic PMS activation was proposed that involved electron transfer from MnO or Mn₂O₃ to PMS with the generation of sulfate radicals, protons and MnO₂, as well as the simultaneous reduction of MnO₂ by PMS.

Keywords: Bisphenol A; Degradation; Heterogeneous catalysis; Manganese oxide; Peroxymonosulfate activation.