TiO_2-硅酸铝纤维纳米复合材料光催化脱硫脱硝脱汞的实验研究  

Study on Photocatalytic Experiments of Desulfurization,Denitrification and Mercury Removal Using a TiO_2-aluminum Silicate Fiber Nanocomposite

作　　者：袁媛[1] 赵永椿[1] 张军营[1] 王宇翔[1] 陈玉民[1] 郑楚光[1] 

机构地区：[1]煤燃烧国家重点实验室(华中科技大学),湖北省武汉市430074

出　　处：《中国电机工程学报》2011年第11期79-85,共7页Proceedings of the CSEE

基　　金：国家自然科学基金项目(40972102;50936001);国家重点基础研究发展计划项目(973项目)(2010CB227003)~~

摘　　要：使用溶胶凝胶法以硅酸铝纤维为载体制备纳米TiO2复合材料,利用X射线衍射仪及场发射扫描电镜对其进行表征。在波长为253.7nm的紫外光照射下使用复合材料脱除模拟燃煤烟气中的SO2,NO和元素Hg,考察了此复合材料的脱硫、脱硝和脱汞效率,以及试验工况对脱除效率的影响。研究结果表明硅酸铝纤维上负载的纳米TiO2主要为锐钛矿相,粒径在20 nm左右。光催化脱硫、脱硝和脱汞效率达到37%、40%和84%。SO2和NO的浓度增加,其光催化脱除效率降低,烟气中低浓度的SO2对NO的脱除起促进作用,而在较高的浓度范围内会抑制光催化脱硝效率;同样随着烟气中NO浓度的逐渐增加,对光催化脱硫也表现出先促进后抑制的作用。温度对光催化氧化有抑制作用,纳米复合材料的脱硫脱硝脱汞效率均随着反应温度的升高而降低。A novel TiO2-aluminum silicate fiber nanocomposite was prepared by sol-gel method. The nanocomposite was characterized by X-ray diffraction and field scanning electron microscopy. Nano TiO2 particles supported on aluminum silicate fiber existed as anatase with a diameter about 20nm. This nanocomposite was used to remove SO2, NO and Hg^0 from simulated flue gas under UV irradiation at a wavelength of 253.7 nm. The desulfurization, denitrification and mercury removal efficiencies and effects of experimental conditions on removal efficiencies were tested. The results showed that the photocatalytic desulfurization, denitrification and mercury removal efficiencies could reach 37%, 40%, and 84% respectively. There were inhibitory effects of high SO2 and NO concentrations on photocatalytic removals of SO2 and NO in simultaneous desulfurization and denitrification. A high SO2 concentration inhibited the removal of NO in the flue gas, so does NO. It was negative effect of high temperature on photocatalytic oxidation reaction. The desulfurization, denitrification and mercury removal efficiencies all decreased as the temperature increased.

关 键 词：纳米TiO2复合材料 光催化 脱硫脱硝 脱汞 

分 类 号：X703[环境科学与工程—环境工程]