State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment (SKLESPC), Tsinghua University, Beijing 100084, China.
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment (SKLESPC), Tsinghua University, Beijing 100084, China.
Ultrason Sonochem. 2014 Jul;21(4):1310-7. doi: 10.1016/j.ultsonch.2014.01.008. Epub 2014 Jan 17.
A novel sonoelectrochemical catalytic oxidation-driven process using a nanocoated electrode to treat methylene blue (MB) wastewater was developed. The nano-scale (nanocoated) electrode generated more hydroxyl radicals than non-nano-scale (non-nanocoated) electrodes did. However, hydroxyl radicals were easily adsorbed by the nanomaterial and thus were not able to enter the solution. Supersonic waves were found to enhance the mass-transfer effect on the nanocoated electrode surface, resulting in rapid diffusion of the generated hydroxyl radicals into the solution. In solution, the hydroxyl radicals then reacted with organic pollutants in the presence of ultrasonic waves. The effect of the nanocoated electrode on the MB wastewater treatment process was enhanced by ultrasound when compared to the non-nanocoated electrode used under the same conditions. The synergy of the nanocoated electrode and ultrasonic waves towards MB degradation was then studied. The optimum operating conditions resulted in a 92% removal efficiency for TOC and consisted of a current of 600 mA, an ultrasound frequency of 45 kHz, and a supersonic power of 250 W. The mechanism of ultrasound enhancement of the nanocoated electrode activity with respect to MB treatment is discussed. The reaction intermediates of the sonoelectrochemical catalytic oxidation process were monitored, and degradation pathways were proposed. The sonoelectrochemical catalytic oxidation-driven process using nanocoated electrodes was found to be a very efficient method for the treatment of non-biodegradable wastewater.
开发了一种使用纳米涂层电极的新型声电化学催化氧化驱动工艺来处理亚甲基蓝（MB）废水。纳米级（纳米涂层）电极比非纳米级（非纳米涂层）电极产生更多的羟基自由基。然而，羟基自由基很容易被纳米材料吸附，因此无法进入溶液。超声波被发现增强了纳米涂层电极表面的传质效应，导致生成的羟基自由基迅速扩散到溶液中。在溶液中，羟基自由基随后在超声波的存在下与有机污染物反应。与在相同条件下使用的非纳米涂层电极相比，超声增强了纳米涂层电极对 MB 废水处理过程的效果。然后研究了纳米涂层电极和超声波对 MB 降解的协同作用。最佳操作条件下，TOC 的去除率达到 92%，电流为 600 mA，超声频率为 45 kHz，超声功率为 250 W。讨论了超声增强纳米涂层电极活性处理 MB 的机制。监测了声电化学催化氧化过程的反应中间体，并提出了降解途径。使用纳米涂层电极的声电化学催化氧化驱动工艺被发现是处理难生物降解废水的一种非常有效的方法。
