使用自制的具有电催化活性和光催化括性TiO2改性的β-PbO2电极,研究了光助电催化氧化过程、电催化氧化过程和光催化氧化过程对于偶氮染料酸性橙Ⅱ的降解.用紫外可见光谱和高效液相色谱分析了3种降解过程中不同的降解行为,对降解产物进行了FTIR和GC-MS分析.结果表明,单独电催化过程不同于其它2种过程。出现了醌类物质的大量累积;而在光助电催化氧化过程中。光催化氧化过程大大抑制了电催化氧化过程中累积的高毒性醌类物质.在2h内,光助电催化氧化过程是其它2种过程TOC去除率的1.56倍,产生了明显的协同作用.3种降解过程遵循相同的降解历程,都经历了产生醌类物质到低分子量有机酸的步骤.
TiO2 modified β-PbO2 electrode,which was characterized by its properties of electro-catalytic oxidation and photocatalytie oxidation (PE), was used for the degradation of Acid Orange Ⅱ by photo-assisted electro-catalytic process, electro-catalytic oxidation process and photocatalytic oxidation process. Their degradation performances were monitored by UV-Vis spectra and HPLC analyses. The degradation products were determined by FTIR and GC-MS. It was proved that the accumulation of the highly toxic quinonic compounds only occurred in the process of electro-catalytic oxidation. In the process of PE, the accumulation of the quinonic compounds was largely inhibited by photocatalytic oxidation. The results revealed that the removal of TOC in PE process was 1.56 times of the sum of the other two processes and a significant synergetic effect was observed. The same degradation pathway was followed by the three processes, which involved the producing of quinonic compounds and the subsequent organic acids.