TiO2-SiO2复合气凝胶的制备及其分解甲基橙的研究

采用溶胶一凝胶工艺，经超临界干燥，600℃、2h煅烧制得TiO2-SiO2复合气凝胶，其中Ti02为锐钛矿型，Si02为无定形；以甲基橙为模拟废水，TiO2-SiO2气凝胶分解甲基橙的浓度范围为≤100mg／L，分解速率随着时间的变化而变化，前期呈线性关系，后期呈曲线关系；最大分解甲基橙的量约为30mg甲基橙／g气凝胶，采用400℃煅烧1h的活化方式可使气凝胶的重复使用寿命大于3次。

Research on Preparation of TiO2-SiO2 Composite Aerogel and Degradation of Methyl Orange

TiO2-SiO2 composite aerogel is prepared in two hours under 600oC by the sol-gel method and supercritical drying technique,among which TiO2 is anatase and SiO2 is amorphous.By using methyl orange as simulated wastewater,the density of degradation of methyl orange by TiO2-SiO2 composite aerogel is less than 100mg/L and degradation rate changes with time,showing liner relationship in the first phase and curve relationship in the latter phase.The maximum dose of degrading methyl orange is about 30mg/g(methyl orange/aerogel).The TiO2-SiO2 composite aerogel can be reused more than three times by adopting calcination method of one hour under 400oC.