MnO_2-UV联用光化学降解苯酚废水的初步研究  

A Preliminary Study on Photochemical Degradation of Phenol in Wastewater by the MnO_2-UV Combination

作　　者：冯雄汉[1] 张嵚[1] 谭军凤[1] 文慧[1] 谭文峰[1] 刘凡[1] 

机构地区：[1]华中农业大学农业部亚热带农业资源与环境重点实验室,武汉430070

出　　处：《矿物岩石地球化学通报》2006年第4期319-323,共5页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家自然科学基金资助项目(40403009);教育部科学技术研究基金重点资助项目(105122)

摘　　要：探讨了人工合成的高价锰氧化物与紫外光(UV)联用时降解苯酚废水的特性。结果表明,氧化锰矿物在无UV时对苯酚的降解能力差异大,1 g/L的氧化锰4 h对200 mg/L苯酚废水的降解率和COD去除率分别为:锰钾矿97.51%、酸性水钠锰矿89.07%、碱性水钠锰矿11.36%、钙锰矿9.67%;锰钾矿87.79%、酸性水钠锰矿53.11%、碱性水钠锰矿6.42%、钙锰矿1.43%。UV光照下,氧化锰矿物对苯酚的降解率有不同程度的提高,且表现出显著的表面光催化性质,增加了苯酚的深度降解,COD去除率显著提高。UV下氧化锰4 h对苯酚的降解率分别为:锰钾矿99.48%、酸性水钠锰矿91.86%、碱性水钠锰矿40.15%、钙锰矿35.95%);COD的去除率分别为:锰钾矿98.11%、酸性水钠锰矿68.45%、钙锰矿27.57%、碱性水钠锰矿24.27%。MnO2-UV联用时降解苯酚可能包括两种主要作用机制:氧化锰矿物的直接化学氧化降解和UV下MnO2的表面光催化降解。This paper has studied the degradation characteristics of phenol in wastewater by different combination of synthetic manganese oxides and UV. The results show that there are significant differences in the degradation abili ty of phenol among the various Mn oxides under no UV condition. The magnitude orders of the degrading rate and COD removing rate of phenol in wastewater under the condition of 1 g/L Mn oxides and 4 hours are decreased from cryptomelane （97.51%）, to acidic birnessite （89.07%）, to alkaline birnessite （11.36%）, to todorokite （9.67%） and from cryptomelane （87.79%）, to acidic birnessite （53.11%）, to alkaline birnessite （6.42%） , and to todorokite （1.43 %）, subsequently. Under UV condition, the degrading rates of phenol in wastewater under the condition of various corresponding Mn oxides are increased in different degrees. The obvious surface photocatalytic property of the Mn oxides has increased the degrading rate of phenol and improved the COD removing rate remarkably. However, the degrading rate of phenol by direct UV photolysis is largely decreased due to the addition of Mn oxide minerals. The degrading rates of phenol by the Mn oxides under UV radiation are subsequently decreased from cryptomelane （99. 48%）, to acidic birnessite （91. 86%）, to alkaline birnessite （40.15%）, and to todorokite （35.95%）. The COD removing rates are decreased from cryptomelane （98.11%）, to acidic birnessite （68.45%）, to todorokite （27.57 %）, and to alkaline birnessite （24.27 %）. It is suggested that two mechanisms may be existed in the degrading of phenol by the MnO2-UV combination. One is the direct chemical oxidization of phenol by MnO2 oxides. Another is the photocatalytic degrading of phenol on the surface of MnO2 oxides.

关 键 词：MNO2 苯酚废水 光催化 降解率 COD去除率 

分 类 号：X703[环境科学与工程—环境工程]