碳纳米管活化过二硫酸盐降解偶氮染料酸性橙7

Decolorization of acid orange 7 by persulfate activated by carbon nanotube

采用碳纳米管(CNT)活化过二硫酸盐(PS)降解偶氮染料酸性橙7(AO7).考察了PS浓度、CNT投加量、初始p H值、温度等反应条件对AO7降解效果的影响.结果表明,当初始p H为7、n(PS)/n(AO7)为20、CNT投加量为0.2g/L时,AO7在反应480min后可以被完全脱色去除.随着PS剂量、CNT投加量和温度的升高,AO7的去除率也逐渐增加,中性条件下最有利于AO7的去除.AO7降解反应主要发生在CNT表面,且反应活化能Ea为46.76k J/mol.通过紫外-可见分光光谱、气相色谱—质谱(GC-MS)和TOC分析表明,AO7分子偶氮键和萘环结构断裂,生成含苯环类物质,最终矿化为CO_2和H_2O.

Carbon nanotube(CNT)was used as an activator to activate persulfate(PS)to decolorize the azo dye,acidorange7(AO7).Effect of PS dosage,CNT loading,initial pH and reaction temperature on decolorization of AO7wasinvestigated.The results indicated that completely decolorization of AO7was achieved within480min when0.2g/L ofCNT and20of n(PS)/n(AO7)were present in the system.AO7decolorization was increased with increasing PS dosage,raising CNT loading and elevating temperature,and neutral pH was most favorable for AO7decolorization.The oxidativedegradation of AO7mainly took place on the surface of CNT and the activation energy(Ea)was determined to be46.76kJ/mol.From the analysis of UV-Vis spectra,GC-MS and TOC during the reaction,the azo band and naphthalenering of AO7were proposed to be destroyed to generate other small intermediate containing benzene,and finallymineralized to CO2and H2O.