Synergistic effects of hybrid photo-electrocatalytic degradation of 3,4-dimethylaniline wastewater
LI Zhaodong1,, LI Meng1, TANG Jianwei1,2,, 1.Department of Municipal Engineering, Wuhan University of Technology, Wuhan 430070, China 2.Unit 95338 of the Chinese People’s Liberation Army, Guangzhou 510405, China
Abstract:The synergistic effects often occur in many advanced oxidation processes, while its mechanisms are still unclear. Hence, in this study, the synergetic level was taken as an indicator, and the effects of illumination, current intensity, aeration intensity and initial pH on the synergistic effects of hybrid photo-electrocatalytic degradation of 3,4-dimethylaniline (3,4-DMA) were determined. Furthermore, photo-assisted electrocatalytic, electro-assisted photocatalytic and hydroxyl radicals detection experiments were carried out to explore the degradation mechanism. The results indicated that the synergistic effects occurred in the hybrid photo-electrocatalysis system, and the synergetic level was affected by external conditions. The reasons for the synergetic effects were ascribed to the following items. The applied electric fields promoted the yield of hydroxyl radicals. The ultraviolet radiation improved the utilization of active oxides such as hydroxyl radicals by stimulating 3,4-DMA and its intermediates. The oxygen evolution side reaction in electrocatalysis provided electron acceptors for photocatalysis, which could enhance the degradation efficiency of the whole treatment system. This research provided a new method for further study and regulation of the synergetic effects. Key words:hybrid photo-electrocatalytic oxidation/ synergistic effects/ oxygen evolution side reaction/ hydroxyl radicals/ photon excitation.
图1光电耦合催化氧化实验装置示意图 Figure1.Schematic diagram of the device of hybrid photo-electrocatalytic experiment
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1.Department of Municipal Engineering, Wuhan University of Technology, Wuhan 430070, China 2.Unit 95338 of the Chinese People’s Liberation Army, Guangzhou 510405, China Received Date: 2018-12-17 Accepted Date: 2019-03-13 Available Online: 2019-08-06 Keywords:hybrid photo-electrocatalytic oxidation/ synergistic effects/ oxygen evolution side reaction/ hydroxyl radicals/ photon excitation Abstract:The synergistic effects often occur in many advanced oxidation processes, while its mechanisms are still unclear. Hence, in this study, the synergetic level was taken as an indicator, and the effects of illumination, current intensity, aeration intensity and initial pH on the synergistic effects of hybrid photo-electrocatalytic degradation of 3,4-dimethylaniline (3,4-DMA) were determined. Furthermore, photo-assisted electrocatalytic, electro-assisted photocatalytic and hydroxyl radicals detection experiments were carried out to explore the degradation mechanism. The results indicated that the synergistic effects occurred in the hybrid photo-electrocatalysis system, and the synergetic level was affected by external conditions. The reasons for the synergetic effects were ascribed to the following items. The applied electric fields promoted the yield of hydroxyl radicals. The ultraviolet radiation improved the utilization of active oxides such as hydroxyl radicals by stimulating 3,4-DMA and its intermediates. The oxygen evolution side reaction in electrocatalysis provided electron acceptors for photocatalysis, which could enhance the degradation efficiency of the whole treatment system. This research provided a new method for further study and regulation of the synergetic effects.