湿式过氧化氢催化氧化降解喹啉及其机理

Quinoline degradation and mechanism in catalytic wet peroxide oxidation system

采用浸渍法制备了负载型铜铁氧化物催化剂,并以喹啉为目标污染物,建立了湿式过氧化氢催化氧化(CWPO)体系。研究了反应温度、初始pH、H2O2和催化剂投加量对喹啉去除效果的影响,并分析了CWPO体系中iOH的作用及喹啉的降解路径。结果表明,CWPO对喹啉具有很好的去除效果,反应30 min喹啉的去除率可达到100%,反应60 min矿化率可达到88.34%。确定了最佳反应温度为80℃,初始pH为7,H2O2和催化剂投加量分别为29.15mmol·L-1和4 g·L-1。iOH氧化在CWPO降解喹啉体系中起主导作用,其平均产生速率为1.69×10-6mmol·L-1·min-1。推测了CWPO降解喹啉的4种可能路径,在中性和酸性条件下,分别生成以吡啶环或苯环为主的中间产物。

In order to study the removal and degradation mechanism of quinoline in catalytic wet peroxide oxidation （CWPO） system, a series of experiments were conducted over CuO-FeOx/γ-Al2O3 catalyst. The influence of reaction temperature, initial pH, dosage of H2O2 and amount of catalyst were investigated, and the role of .OH and degradation pathways of quinoline were analyzed. CWPO had good removal efficiency for quinoline. A complete quinoline conversion and 88.34% total organic carbon （TOC） removal were achieved in 60 min with initial pH of 7, 29.15 mmol · L^-1 of H202 and 4 g · L^-1 of catalyst at 80℃. ·OH oxidation played a dominant role in quinoline degradation in CWPO system, and its average production rate was 1.69×10^-6mmol·L^-1·min^-1. Under neutral and acidic conditions, quinoline degradation in CWPO system followed different pathways, and generated pyridine-based or benzene-based intermediate products.