混凝辅助电化学法处理橙黄G染料废水

以石墨板为阳极，研究了电化学氧化法对橙黄G染料废水的降解效果。比较了在NaCl、Na2 SO4以及NaCl与FeSO4·7H2O组合的支持电解质体系中的处理效果，同时考察了电压、初始pH、电解质浓度、电极间距和电解时间等因素对废水中橙黄G脱色率及COD去除率的影响。研究结果表明，橙黄G的脱色主要是活性氯的氧化作用，橙黄G分子的矿化可能主要是电解过程中产生的·OH的作用，FeSO4·7H2O的加入增加了混凝作用，使得处理效果进一步提高。最佳脱色条件下橙黄G脱色率和COD的去除率分别为97．6％和56．3％，B／C（BOD／COD）由0．09提高至0．41，可生化性有较大改善，并且随着降解时间的增加，COD去除率逐渐升高。此结果表明，橙黄G废水COD的去除相对于脱色存在滞后性。

Treatment of Orange G dye wastewater by electrochemical process with auxiliary coagulation

The degradation effect of Orange G dye wastewater by electrochemical oxidation process with a graphite plate as anode was studied. The treatment effects in supporting electrolytes systems of NaCl, Na2SO4 and NaCl ＆ FeSO4 - 7H2O combinations were compared. Meanwhile, effects of factors such as voltage, initial pH, concentration of electrolytes, spacing between electrodes and electrolysis time on the decolorization of Or- ange G and the degradation of COD in the wastewater were also investigated. The results show that the decolori- zation of Orange G may mainly owe to the oxidation of active chlorine, and the mineralization of Orange G may owe to the action of . OH generated during the electrolysis process. With the addition of FeSO4. 7H2O, the co- agulation function is enhanced, which further improves the treatment effect. Under the optimal decolorization conditions, the decolorization rate of Orange G and the removal efficiency of COD are 97.6% and 56.3% , re- spectively. Moreover, biodegradability is significantly improved with the B/C（BOD/COD） increased from 0.09 to 0.41. Besides, the removal efficiency of COD increases gradually with the increase of time. This result indi- cates that the removal of COD is hysteretic with respect to the decolorization in Orange G wastewater.