采用掺硼金刚石膜（BDD）阳极对含吲哚废水进行电化学氧化，基于吲哚去除率及能耗两方面的考虑，通过正交实验确定氧化吲哚的最佳工艺条件为：电流密度30 mA ／cm2，电解质浓度0．04 mol／L，电解时间2 h。随电解时间的增加，废水 BOD5／COD 值从初始的0．04提高至2 h 的0．65，电解出水的活性污泥比耗氧速率与葡萄糖对照样相比，差别越来越小，废水的生物毒性显著降低。通过 GC-MS 分析了电解过程中吲哚的氧化途径，即吲哚首先被氧化生成羟吲哚和2-羟吲哚，随之得到靛红，之后氮环断裂生成苯胺，进而氧化为苯醌、羟胺，最终转化为氨类、二氧化碳、水等小分子化合物。%A boron-doped diamond anode was adopted for treatment of indole wastewater,and considering the efficiency of the removal of indole and energy consumption,optimum operational conditions of indole oxidation were confirmed as current density of 30 mA /cm2 ,electrolyte concentration of 0.04 mol /L, electrolysis time of 2 h in an orthogonal test.Effluent characteristics were investigated at different electrol-ysis time.The BOD5 /COD value of wastewater increased from an initial value of 0.04 to 0.65 at 1 20 min.Meanwhile,the difference of specific oxygen consumption rate of activated sludge between elec-trolytic effluent and glucose control sample became smaller and smaller,which indicated that the biologi-cal toxicity of wastewater significantly reduced.Finally,the oxidative pathway of indole was analyzed by means of GC-MS,namely,indole firstly was oxidized into oxindole and 2-oxindole,and then isatin was generated,after that nitrogen ring was fractured and aniline was obtained,and then it was oxidized to benzoquinone and hydroxylamine,which was eventually transferred to small molecule of ammonia,carbon dioxide,water and other compounds.
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