双氧水-高锰酸钾催化氧化降解地下水中硝基苯的效能与机理

Degradation efficiency and mechanism of nitrobenzene in underground water by catalysis oxidation of hydrogen peroxide-potassium permanganate

应用双氧水-高锰酸钾(H2O2-KMnO4)催化氧化作用,对地下水中硝基苯(NB)的降解效果和作用机理进行了研究,探讨了H2O2、KMnO4的不同浓度、不同pH值以及地下水中比较有代表性的共存离子钙(Ca2+)、镁(Mg2+)、铜(Cu2+)、锌(Zn2+)、重碳酸根(HCO3-)、碳酸根(CO23-)等因素对NB氧化降解效果的影响。结果表明,H2O2-KMnO4催化氧化作用能有效地降解地下水中NB,反应过程中产生的羟基自由基(HO.)符合自由基作用机理。本实验条件下,在pH=6、H2O2和KMnO4浓度分别为3 mg/L和1 mg/L时,反应60 min,H2O2-KMnO4催化氧化降解NB的效率可达90%以上。

The efficiency and mechanism on degradation of nitrobenzene in underground water were investigated by the catalysis oxidation of hydrogen peroxide-potassium permanganate（H2O2-KMnO4）.The influence law on degradation efficiency of nitrobenzene in underground water were discussed under different concentrations of KMnO4 and H2O2,different pH values and more representative coexist such as calcium ion（Ca^2＋）,magnesium ion（Mg^2＋）,copper ion（Cu^2＋）,zinc ion（Zn^2＋）,bicarbonate ion（HCO3^-）,carbonate ion（CO3^2-） etc.The results showed that the catalysis oxidation of H2O2-KMnO4 could degrade availably nitrobenzene in underground water.The hydroxyl free radical（HO·） produced in the course of reaction is accorded with the mechanism of free radical function.Under such condition of the experiment,the efficiency reached above 90% adopting H2O2-KMnO4 to catalysis oxidation degradation nitrobenzene when pH was 6,H2O2 and KMnO4 concentrations were 3 mg/L and 1 mg/L,respectively and reacting time was 60 minutes.