【摘要】 采用间接阳极氧化处理活性染料模拟废水,以自制钛基IrO₂电极为阳极,石墨为阴极,NaCl为支持电解质,考察了Ti/IrO₂电极间接阳极氧化活性橙X-GN模拟废水的处理效果,研究了pH值、电压、电解时间及NaCl投加量对其降解效果的影响。结果表明,在pH值为3,电压为20V,NaCl投加量为2.5g/L,室温条件下,电解30min后该染料的脱色率达到100%,电解60min后COD去除率可达68%。在本试验条件下,染料通过电解产生的Cl₂、ClO^-、HClO等物质间接氧化降解。为探讨电化学氧化降解活性橙X-GN的过程,对该染料的降解过程进行UV-Vis光谱分析,初步探讨了该染料的降解规律。在电解过程中,染料的发色偶氮共轭体系首先被破坏,染料溶液的颜色逐渐褪去;经偶氮双键形成的共轭体系被破坏的同时,染料结构中的苯环结构、均三嗪结构以及萘环结构也遭到破坏,UV-Vis光谱中各基团的特征吸收峰基本消失;反应60 min后,UV-Vis光谱中已无明显吸收峰,表明该染料降解效果较好。更多还原

【Abstract】 This paper aims at studying how to apply the indirect anodic oxidation method to treating the simulated sewage with reactive orange X-GN. For this purpose, we have first of all studied the influence of pH value, voltage, electrolysis time and NaCl dosage on the degradation behaviors. At the same time, a special discussion has been given to the working principles of the degradation and satisfactory de-colorization effect of dyeing sewage, a kind of intractable industrial sewage with high color, complex components seriously damaging to the environment. As we know, electrochemical oxidation is an advanced oxidation process that has been developed and perfected in recent years. It has found wide application in chemical industry due to its distinguished characteristics, such as highly efficient, convenient in operation and environment-friendly. And, therefore, the above outstanding features of the method made us use the indirect anode oxidation to treat the simulated sewage with reactive orange X-GN dye. In proceeding with our research, we have investigated the effect of the treatment of such sewage by indirect anodic oxidation with Ti/ IrO₂ as anode, graphite as the cathode and NaCl supporting electrolytes. The results of our experiments show that the decolorization rate of the dye can get to 100% after 30 min treatment with the removal rate of COD rising to 68% after 60 min treatment under the condition with the pH value being 3 , the voltage—3 V, the concentration of NaCl—2.5 g/L at room temperature. The dye proves to be degraded by using indirectly oxidized electro-generated substances such as Cl₂, ClO^-, HClO. And, last of all, we have also made careful analysis of the dye s degrading process by means of UV Vis spectroscopy, trying to find its degrading regularity. It has been found that the conjugated chromophore of the dye’s scilicet azo double bond was first broken in the oxidation process, and then the dye got dissolved. At the same time, the benzene ring, s-triazine structure and naphthalene ring turned to be broken too, which eventually led the characteristic absorption peaks of the groups in UV-Vis spectrum to disappear. After 60 min treatment, the benzene ring of reactive orange X-GN would naturally get degraded, since no more noticeable characteristic peaks remain in its UV-Vis spectrum.更多还原