(1. 中南大學 冶金科學與工程學院，長沙 410017；
2. 國家重金屬污染防治工程技術(shù)研究中心，長沙 410017；
3. 長沙市審計局，長沙 410013)
摘 要: 開發(fā)三維電極法降解苯酚新工藝，用電化學方法研究苯酚降解的機理。結(jié)果表明：采用預處理后的活性炭作為粒子電極，在進水pH值6~7、進水流量180 mL/min、水溫25 ℃、氯化鈉加入量1 g/L、電流100 mA的條件下，電解1.5 h后總有機碳(TOC)的去除率可以達到95%以上。電解過程活性炭陽極生成羥基自由基(·OH)并吸附在活性炭上，與吸附在活性炭上的苯酚形成微電池。通過微電池反應，苯酚首先被降解成鄰苯二酚、間苯二酚、對苯二酚等中間產(chǎn)物，進而又被礦化為CO2和H2O。同時，陽極極化曲線表明苯酚也可在陽極氧化，但羥基自由基對苯酚的降解起主要作用。
關(guān)鍵字: 三維電極；苯酚廢水；有機物降解；羥基自由基
（1. School of Metallurgical Science and Engineering, Central South University, Changsha 410017;
2. National Engineering Research Center for Pollution Control of Heavy Metals, Changsha 410017;
3. Changsha Municipal Audit Bureau, Changsha 410013, China）
Abstract:The degradation technology of phenol in wastewater via three-dimensional electrode reactor was proposed, and then the degradation mechanism of phenol was investigated by the electrochemical methods. The results show that the removal efficiency of total organic carbon (TOC) can reach 95% under conditions of pH 6−7, influent flow rate of 180 mL/min, 25 ℃, NaCl dosage of 1 g/L, electric density of 100 mA and electrolysis time for 1.5 h, and using the pretreated activated carbon as particle electrode. The hydroxyl radicals are generated and adsorbed on the surface of activated carbon electrode during the process of electrochemical degradation. Meanwhile, the micro-batteries are formed by the radicals and adsorbed phenol. In the micro-cell, firstly phenol is degraded into the intermediates, such as catechol, resorcinol and hydroquinone, and then those intermediates are mineralized into CO2 and H2O. Furthermore, the anodic polarization curves show that phenol can be oxidized at the anode surface. However, the hydroxyl radical is the major contributor for phenol degradation.
Key words: three-dimensional electrode; phenol-containing wastewater; organics degradation; hydroxyl radical
