National Engineering Research Center for Urban Pollution Control, Tongji University, Shanghai 200092, China.
J Environ Sci (China). 2010;22(2):204-10. doi: 10.1016/s1001-0742(09)60094-2.
A study on the electrochemical disinfection with H2O2 generated at the gas diffusion electrode (GDE) from active carbon/polytetrafluoroethylene was performed in a non-membrane cell. The effects of Pt load and the pore-forming agent content in GDE, and operating conditions were investigated. The experimental results showed that nearly all bacterial cultures inoculated in the secondary effluent from wastewater treatment plant could be inactivated within 30 min at a current density of 10 mA/cm2. The disinfection improved with increasing Pt load. Addition of the pore-forming agent NH4HCO3 improved the disinfection, while a drop in the pH value resulted in a rapid rise of germicidal efficacy and the disinfection time was shortened with increasing oxygen flow rate. Adsorption was proved to be ineffective in destroying bacteria, while germicidal efficacy increased with current density. The acceleration rate was different, it initially increased with current density. Then decreased, and finally reached a maximum at a current density of 6.7 mA/cm2. The disinfection also improved with decreasing total bacterial count. The germicidal efficacy in the cathode compartment was approximately the same as in the anode compartment, indicating that the contribution of direct oxidation and the indirect treatment of bacterial cultures by hydroxyl radical was similar to the oxidative indirect effect of the generated H2O2.
在非膜电池中，使用活性炭/聚四氟乙烯制成的气体扩散电极（GDE）产生的 H2O2 进行电化学消毒的研究。考察了 Pt 负载量和 GDE 中的造孔剂含量以及操作条件的影响。实验结果表明，在电流密度为 10 mA/cm2 时，几乎所有接种在废水处理厂二级出水的细菌培养物都可以在 30 min 内失活。随着 Pt 负载量的增加，消毒效果得到改善。添加造孔剂 NH4HCO3 提高了消毒效果，而 pH 值下降导致杀菌效果迅速提高，随着氧气流量的增加，消毒时间缩短。吸附被证明对破坏细菌无效，而杀菌效果随电流密度的增加而增加。加速率最初随电流密度增加而增加。然后降低，最后在电流密度为 6.7 mA/cm2 时达到最大值。随着总细菌计数的减少，消毒效果也得到改善。阴极室的杀菌效果与阳极室大致相同，表明直接氧化和羟基自由基间接处理细菌培养物的贡献与生成的 H2O2 的氧化间接效应相似。
