Efficient Degradation of 2,4-Dichlorophenol on Activation of Peroxymonosulfate Mediated by MnO(2).

Affiliation

Liu J(1)(2), An F(3), Li M(1), Yang L(1), Wan J(1), Zhang S(4).
Author information:
(1)Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing, 210042, China.
(2)School of Environmental Science, Nanjing XiaoZhuang University, Nanjing, 211171, China.
(3)State Power Environmental Protection Research Institute Co. Ltd., Nanjing, 210031, China.
(4)Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing, 210042, China. [Email]

Abstract

Sulfate radical based-advanced oxidation process has received increasing interest in the remediation of wastewater and contaminated soil. In this study, degradation of 2, 4-dichlorophenol (2, 4-DCP) was investigated over peroxymonosulfate (PMS) activation by MnO2, which was prepared by liquid-phase oxidation method. The prepared MnO2 was characterized by transition electron microscopy, X-ray diffraction, N2 adsorption-desorption, and X-ray photoelectron spectroscopy. Characterization results showed that α-MnO2 exhibited the highest surface area and Mn (III) content. The PMS activation by MnO2 in 2, 4-DCP degradation followed the order of α-MnO2 >  γ-MnO2 > β-MnO2, which is dependent on the properties of MnO2 including crystal structure, surface area and Mn (III) content. Influences of initial concentration of 2, 4-DCP, PMS and MnO2 dosage, pH and co-existing inorganic ions on the degradation were examined. Electron paramagnetic resonance (EPR) and quenching experiments with ethanol and tert-butanol suggested that sulfate radicals were the dominant radicals in the process. Findings in this study indicated that α-MnO2 was an attractive catalyst for activation of PMS to degrade 2, 4-DCP in aqueous solution.