可回收高温型二氧化钛光催化材料的制备及表征

PREPARATION AND CHARACTERIZATION OF RECOVERABLE AND HIGH TEMPERATURE TITANIUM DIOXIDE PHOTO CATALYST

用钛酸四丁酯为前驱体,采用溶胶-凝胶法制备二氧化钛光催化剂,以硅灰粉尘为载体,经高温烧结制备可回收、可用于高温场合的二氧化钛光催化材料,主要探讨光催化剂与载体的不同比例对材料的催化活性的影响。通过紫外灯照射下甲基橙溶液光催化降解率来表征样品的光催化活性能,用氮脱吸附法测定样品的比表面积,采用X射线粉末衍射分析二氧化钛的晶型,用扫描电镜观察样品的微观形貌。实验结果确定硅微粉与TiO2的合成比例为7∶3,其比表面积达到26.65m2/g;用15W的紫外灯照射24小时后可使甲基橙溶液退为无色,降解率达到99.1%。

A kind of recoverable Titanium Dioxide Photocatalyst which can used at high temperatures was prepared by using Ti（BuO）4 as precursor and fine silicon dust as carrier by following sol-gel rutine. In this paper the influence of different proportions of fine silicon dust to TiO2 on the structure and properties of photocatalyst were mainly discussed. The photocatalytic activity of the samples was measured by the photocatalytic degradation rate of methyl orange under UV irradiation. The Specific Surface Area （SSA） was determined based on the isothermal adsorption of nitrogen. X-ray diffraction was used to identify the crystal structure of titanium dioxide. Microstructures were examined by Scanning Electron Microscopy （SEM）. The results The most photocatalyticly active sample is made of 3 ： 7 TiO2 to fine silicon powder. Under the exposure of 15 W ultraviolet irradiation for 24 hours, the 10ml·L^-1 Methyl Orange entirely lost its color with a degradation rate of 99.1%. The corresponding SSA is 26.65m^2/g. SEM micrographs reveal that this composition has the most uniform dispersion with the largest amount of small particles.