钛基体PbO2电极对靛蓝盐的电催化去除研究
Electrochemical Degradation of Indigo Salt by Titanium？？Based PbO2 Anode

以钛基体PbO2为阳极,对靛蓝盐模拟废水进行电催化氧化处理,主要考察靛蓝盐的电催化去除机制及相关因素对去除效果和单位能耗值的影响。CHI 660D电化学工作站线性扫描曲线与叔丁醇加入实验结果表明:靛蓝盐的电催化过程是直接氧化与间接氧化并存的过程,以间接氧化为主;电流密度的增加有利于提高靛蓝盐的电催化去除效果,却使得单位能耗值增加;靛蓝盐浓度的增加会降低其电催化氧化的效果,却有利于降低单位能耗值;温度升高对靛蓝盐去除率无影响,但会使得单位能耗值降低。在全部实验结果中,靛蓝盐的去除率远高于化学需氧量(COD)的去除率,且单位靛蓝盐去除能耗值低于单位COD去除能耗值,表明靛蓝盐脱色过程比COD去除过程容易。
PbO2 electrode was adopted as the anode for the electro？？catalytic oxidative degradation of indigo salt. The main purpose was to study the variations of the UV？？vis spectrum and the degradation mechanism of indigo salt on PbO2 anode. The influences of different factors on the degradation and energy consumption were considered. The results indicated that indigo salt was oxidized by both the direct electron exchange reaction on electrode surface and the hydroxyl radicals produced on the electrode surface through indirect oxidation mechanism. The increase of current density could promote indigo salt degradation and chemical oxygen demand (COD) removal, and also lead to an apparent increase of unit energy consumption. The removal efficiencies of indigo salt and COD could be reduced through the increase of dye concentration but the unit energy consumption was decreased accordingly, indicating that the high concentration of organics is beneficial to the decrease of the unit energy consumption in electro？？catalytic reactions. The temperature rise could not enhance the degradation and removal of organics. However, it was beneficial to the decrease of unit energy consumption. In the experiments, the indigo salt degradation efficiency was higher than the COD removal efficiency, and the unit energy consumption of indigo salt degradation was lower than that of COD removal, indicating that the organic removal process is easier than that of COD