基于Ti/SnO_2阳极氧化法的典型染料废水电化学氧化规律

采用Ti/SnO2电极间接阳极氧化法处理直接深棕M和活性艳蓝KNR模拟染料废水,研究电解质种类、pH、电压、NaCl投加量及电解时间对其降解效果的影响;在最佳组合条件下,通过分析UV-Vis光谱以及降解过程中氮元素的存在形式,研究上述2种染料的降解规律。结果表明,在pH为3,电压20 V,NaCl投加量为2.5 g/L的条件下,电解30 min后,直接深棕M和活性艳蓝KNR的脱色率分别达到80%和95%,60 min后直接深棕M的COD去除率可达75%,活性艳蓝KNR的COD去除率达到90%;电解60 min后,直接深棕M的偶氮双键完全破坏,萘环和苯环结构被逐步降解,活性艳蓝KNR溶液电解2 min,其分子结构中的蒽醌共轭体系被破坏,随反应的进行,蒽醌结构逐渐被破坏,染料逐步降解。

Electrochemical oxidation rule of representative dye wastewater with Ti/SnO2 as anode

Ti/SnO₂ was employed as anode to electrolyze simulated dye wastewater containing Direct Dark Brown M (DDB-M) and Reactive Brilliant Blue KNR (RBB-KNR) by the method of indirect anode oxidation.The influences of the type of electrolytes, pH value, voltage, NaCl dosage, and electrolysis time on the degradation performance were explored.Under the optimal condition, degradation rule of the two dyes was analyzed by investigating the existance form of nitrogen and UV-Vis spectra.After being electrolyzed for 30 min (at the pH value of 3, the voltage of 20 V, the concentration of NaCl 2.5 g/L), the decolourization of DDB-M and RBB-KNR reached 80% and 95%, respectively; 60 min later, the COD removal of DDB-M and RBB-KNR achieved 75% and 90%, respectively.The azo double bond of DDB-M was completely broken, the benzene ring and naphthalene ring were gradually broken during electrolytic oxidation process.As the electrolysis process continued, the anthraquinone conjugated structure of RBB-KNR began to be gradually broken at 2 min, and then the dye was degraded step by step.