纳米TiO_2/硅藻土光催化降解废水中二甲胺  

Photocatalytic degradation of dimethylamine in wastewater with nano-TiO_2/diatomite

作　　者：李霞[1] 胡勤海[1] 陈菊芬 刘苗[1] 宋雪斐[1] 张荣臻[1] 

机构地区：[1]浙江大学环境与资源学院,杭州310058 [2]浙江玉环县环保局,玉环317600

出　　处：《环境工程学报》2013年第8期3073-3078,共6页Chinese Journal of Environmental Engineering

基　　金：浙江大学与杭州金枫叶科技有限公司合作项目

摘　　要：通过凝胶-溶胶法制备纳米TiO2/硅藻土复合催化剂,对常见工业难降解有机污染物二甲胺(DMA)进行了降解实验。采用扫描电镜和X射线衍射技术对催化剂能进行了表征,考察了废水初始浓度、pH、催化剂用量、外加氧化剂对DMA光催化降解效果的影响,进行了降解动力学和降解机理的分析。结果表明,所制催化剂为锐钛矿和金红石混合晶型,均达纳米级,对中低浓度(≤400 mg/L)DMA废水具有良好的降解效果。常温常压、18 W紫外汞灯下,3 g/L TiO2/硅藻土对DMA废水(400 mg/L)降解率可达70%以上;其降解反应符合Langmuir-Hinshelwood动力学模型;其可能的降解途径为:二甲胺(DMA)→甲胺(MA)→CO2/CO32-、H2O和NH4+。The dimethylamine（DMA） is a kind of commonly but hardly decomposed industrially organic pollutant.TiO2/diatomite was prepared by sol-gel method in order to decompose DMA of low concentration（≤400 mg/L）,which was characterized by SEM and XRD.Influences of initial concentration,pH,photocatalyst amount and additional oxidant on photocatalytic activity were investigated.Kinetics and degradation mechanism were also analyzed.Prepared TiO2/diatomite was mixed crystal of anatase and rutile in nano level.The degradation rate of 400 mg/L DMA was up to about 70% with 3 g/L TiO2/diatomite under normal conditions.The photocatalytic degradation matched the Langmuir-Hinshelwood kinetic model and its process was dimethylamine（DMA）→methylamine（MA）→CO2/CO32-,H2O and NH＋4.

关 键 词：二甲胺(DMA) 纳米材料 光催化 二氧化钛(TiO2) 硅藻土 

分 类 号：X783.3[环境科学与工程—环境工程]