介孔TiO_2分子筛前驱体的热处理研究  

Thermal Treatment Study for the Precursor of Mesoporous Titania

作　　者：田从学[1] 张昭[1] 何菁萍[1] 陈垚翰[1] 

机构地区：[1]四川大学化工学院

出　　处：《稀有金属材料与工程》2006年第A02期185-189,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金资助(50474071)

摘　　要：以工业TiOSO4液为原料,控制溶液pH值使TiOSO4液在复合模板剂十二胺和CTAB自组装超分子诱导作用下水解、缩聚和组装,制备出介孔TiO2前驱体。根据TG-DTG和DSC热分析结果确定对前驱体采用两步热处理方案。产物采用XRD、粒度分布、SEM及等温N2吸附进行分析表征。研究表明:在实验温度范围内,前驱体经热处理脱模后均得到锐钛型介孔TiO2,热处理温度的提高和时间的增长使产物结晶度增高,晶粒长大,但其介孔孔道逐渐收缩并坍塌破坏。采用350℃热处理1 h,500℃热处理1 h的热处理方案所得介孔TiO2的晶型与锐钛型TiO2标准物的最接近,晶粒尺寸L101=19．90 nm;粉末呈类球形,平均粒径为0．552μm;其介孔孔道分布窄,平均孔径为3．86 nm,BET比表面积为156．51 m2／g,孔容0.35 cm3/g。On a composite surfactant templates （N-DA and CTAB）, the precursor of mesoporous TiO2 was synthesized via supra-molecular self-assembly route. Hydrolysis and poly-condensation reaction of aqueous TiOSO4 solution from industrial raw material were gradually generated on the micelle of composite surfactant templates through controlling pH value of the reaction system. Anatase mesoporous titania was prepared after templates removal via two-step thermal treatment, determined by TG-DTG and DSC thermo-analysis. The as-prepared powder was characterized by XRD, particle size distribution tests, SEM and N2 absorption and desorption methods. The results indicate that all products are anatase mesoporous titania after templates removal by calcinations over a range of the experimental temperature. The crystallinity and grain size are improved, but the mesoporous structure is gradually shrunken and collapsed. And the crystal form of product B, treated at 350℃ for lh and 500℃ for 1 h, is consistent with that of the standard anatase, the crystal size is 19.90 nm. The average particle size is 0.552 μm and the particles display analogous sphericity. And it has a narrow pore size distribution with specific surface area of 156.3 1m^2/g, average pore diameter of 3.86nm and pore volume of 0.35 cm^3/g.

关 键 词：介孔TIO2 TiOSO4 复合模板剂 热处理 

分 类 号：O614.411[理学—无机化学]