Highly efficient removal and detoxification of phenolic compounds using persulfate activated by MnOx@OMC: Synergistic mechanism and kinetic analysis

Pu-Can Guo; Hai-Bin Qiu; Chuan-Wang Yang; Xin Zhang; Xin-Yue Shao; Yang-Li Lai; Guo-Ping Sheng

doi:10.1016/j.jhazmat.2020.123846

Highly efficient removal and detoxification of phenolic compounds using persulfate activated by MnO_x@OMC: Synergistic mechanism and kinetic analysis

J Hazard Mater. 2021 Jan 15:402:123846. doi: 10.1016/j.jhazmat.2020.123846. Epub 2020 Sep 2.

Authors

Pu-Can Guo¹, Hai-Bin Qiu², Chuan-Wang Yang², Xin Zhang¹, Xin-Yue Shao², Yang-Li Lai², Guo-Ping Sheng³

Affiliations

¹ CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei, 230026, China; Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, 230026, China.
² CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei, 230026, China.
³ CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei, 230026, China; Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, 230026, China. Electronic address: gpsheng@ustc.edu.cn.

PMID: 33254818
DOI: 10.1016/j.jhazmat.2020.123846

Abstract

Persulfate-based advanced oxidation technology exhibits great potential for hazardous organic pollutant removal from wastewater. Acceleration of pollutant degradation needs to be elucidated, particularly for heterogeneous catalytic systems. In this study, manganese oxide ordered mesoporous carbon composites (MnO_x@OMC) were prepared by nano-casting method and used for persulfate activation to degrade phenol. Kinetics analysis indicate that the rate of phenol degradation using MnO_x@OMC composites was improved by 34.9 folds relative to that using a mixture of MnO_x and OMC. The phenol toxicity towards Caenorhabditis elegans could be totally reduced within 8 min. The different roles of MnO_x and OMC in persulfate activation were confirmed to validate their synergistic effect. MnO_x provided major active sites for persulfate activation in accordance with the surface Mn³⁺/Mn⁴⁺ cycle to induce SO₄^•- radicals. The OMC matrix provided the adsorption sites to enrich phenol molecules on the catalytic surface and promote the interfacial electron transfer process for persulfate activation. Moreover, a novel kinetic model with two distinct kinetic stages was established to verify the effects of phenol and persulfate on phenol removal.

Keywords: Detoxification; Heterogeneous catalyst; Manganese oxides; Ordered mesoporous carbon; Persulfate; Synergistic effect.

Publication types

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