Oxidant or catalyst for oxidation? The role of manganese oxides in the activation of peroxymonosulfate (PMS)

Abstract

Manganese oxides (MnO_x) have been demonstrated to be effective materials to activate Oxone (i.e., PMS) to degrade various contaminants. However, the contribution of direct oxidation by MnO_x to the total contaminant degradation under acidic conditions was often neglected in the published work, which has resulted in different and even conflicting interpretations of the reaction mechanisms. Here, the role of MnO_x (as both oxidants and catalysts) in the activation of Oxone was briefly discussed. The findings offered new insights into the reaction mechanisms in PMS-MnO_x and provided a more accurate approach to examine contaminant degradation for water/wastewater treatment.

Keywords

Peroxymonosulfate / Manganese oxides / Catalyst, Oxidant

References

[1] Huang J, Dai Y, Singewald K, Liu C C, Saxena S, Zhang H (2019). Effects of MnO₂ of different structures on activation of peroxymonosulfate for bisphenol A degradation under acidic conditions. Chemical Engineering Journal, 370: 906–915

[2] Huang J, Zhong S, Dai Y, Liu C C, Zhang H (2018). Effect of MnO₂ phase structure on the oxidative reactivity toward bisphenol A degradation. Environmental Science & Technology, 52(19): 11309–11318

[3] Khan A, Wang H, Liu Y, Jawad A, Ifthikar J, Liao Z, Wang T, Chen Z (2018). Highly efficient a-Mn₂O₃@a-MnO₂-500 nanocomposite for peroxymonosulfate activation: Comprehensive investigation of manganese oxides. Journal of Materials Chemistry. A, Materials for Energy and Sustainability, 6(4): 1590–1600

[4] Luo S, Duan L, Sun B, Wei M, Li X, Xu A (2015). Manganese oxide octahedral molecular sieve (OMS-2) as an effective catalyst for degradation of organic dyes in aqueous solutions in the presence of peroxymonosulfate. Applied Catalysis B: Environmental, 164: 92–99

[5] Sabri M, King H J, Gummow R J, Lu X, Zhao C, Oelgemöller M, Chang S L Y, Hocking R K (2018). Oxidant or catalyst for oxidation? A study of how structure and disorder change the selectivity for direct versus catalytic oxidation mediated by manganese (III, IV) oxides. Chemistry of Materials, 30(22): 8244–8256

[6] Wang L, Jiang J, Pang S Y, Zhou Y, Li J, Sun S, Gao Y, Jiang C (2018). Oxidation of bisphenol A by nonradical activation of peroxymonosulfate in the presence of amorphous manganese dioxide. Chemical Engineering Journal, 352: 1004–1013

[7] Zhang H, Chen W R, Huang C H (2008). Kinetic modeling of oxidation of antibacterial agents by manganese oxide. Environmental Science & Technology, 42(15): 5548–5554

Acknowledgements

This material is based upon work supported by the National Science Foundation under Grants CBET-1762691 and CHE-1808406 to H. Zhang.

RIGHTS & PERMISSIONS

2019 Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature