氧气-阳极协同氧化体系中有机染料的降解行为

Degradation behavior of organic dyes in the O2-coupled anodic oxidation process

以石墨碳毡为阳极,采用氧气-阳极协同氧化法对亚甲基蓝(MB)、结晶紫(CV)和罗丹明B(RhB)进行降解,研究了不同电压下染料的降解动力学和降解途径。结果表明,染料在降解初期符合一级动力学特征,且其降解速率随电压的升高而加快。1.8、2.0 V电压下,MB和CV在12 h内脱色率达到100%,而RhB在3 h内脱色完全。染料在体系中主要通过N-去甲基化/去乙基化和发色团解离途径被部分降解。

O2-coupled anodic oxidation process with the graphite felt as anode was used to degrade three organic dyes with different structures,including methylene blue(MB),crystal violet(CV)and Rhodamine B(RhB).The degradation kinetics and pathways of dyes are investigated under different voltages.The results show that the decolorization of dyes fits the first-order kinetic model at the initial stage,and its degradation rate increases with the increase of applied voltage.At 1.8 V and 2 V voltage,the total decolorization of MB and CV solution is achieved within 12 h,and the total decolorization of RhB is achieved even within 3 h.The dyes are partially degraded in the system through the Ndemethylation/N-deethylation and chromophore dissociation.