银掺杂TiO_2催化剂的制备表征及其光催化消除甲醇  

Preparation,characterization of titanium oxide modified by silver and their performance for photo-catalytic elimination of methanol

作　　者：彭振山[1] 韦宗元[1] 李明[1] 吕桃林[1] 蔡铁军[1] 

机构地区：[1]湖南科技大学化学化工学院,湖南湘潭411201

出　　处：《湖南科技大学学报（自然科学版）》2009年第1期111-115,共5页Journal of Hunan University of Science And Technology：Natural Science Edition

基　　金：湖南省教育厅重点科学研究项目(06A015);湖南省有机重点学科资助

摘　　要：采用溶胶-凝胶法制备了Ag/TiO2粉体光催化剂,用差热-热重、红外光谱、固体紫外可见光谱等对其进行表征.用甲醇的光催化降解反应作为模型反应,评价了掺银改性TiO2的光催化活性.考察了活化时不同焙烧温度、时间等对Ag/TiO2光催化消除甲醇的影响.实验结果表明,Ag与TiO2的物质的量之比为0.024、活化的焙烧温度为400℃,焙烧时间为3h的催化剂性能最好,能在紫外光照射下催化消除初始浓度为6.86g·m-3,流速为15mL·min-1的甲醇,消除率为98.6%,达到国家排放标准.当甲醇的浓度在4.49g·m-3、流速为15mL·min-1时,消除率达到100%.图8,参16.The Ag/TiO2 power catalyst was prepared by the sol-gel method, which was characterized by differential thermal-thermogravimetric analysis, infrared spectroscopy,canning electron microscope, UV-vis diffuse reflectance spectrum. The photocatalytic elimination of the methanol was used as a model reaction to evaluate the photocatalytic activity of the Ag/TiO2 power catalyst under ultraviolet light irradiation. The effects of doped content, activation temperature and time, initial concentration of methanol and gas flow rate on the catalytic activity were investigated. The results show that the catalytic activity of Ag/TiO2 power catalyst is significantly higher than un-doped TiO2, the photocatalytic activity of the TiO2 gets enhanced by doping moderate Ag. When molar fraction Ag ： TiO2 is 0.024, the catalyst activated at 400℃ for 3 h has the best catalytic activity. When the initial concentration of methanol is 6.86 g/m^3,the elimination of the methanol is basically completed under the flow rate of 15 mL/min over the 0.1 g Ag/TiO2 power catalyst, which conforms to the requirements of emission standards for air pollutants. When its initial concentration is 4.49 g/m^3 and the flow rate is 15 mL/min, the conversion rate of the methanol is 100%, which has been mineralized completely.

关 键 词：掺杂 二氧化钛 银 光催化消除 甲醇 

分 类 号：O643[理学—物理化学]