溶胶-凝胶法制备多孔SiO2超细粉体
来源期刊：中南大学学报(自然科学版)1998年第2期
论文作者：赵秦生 李中军 刘长让
文章页码：29 - 32
关键词：溶胶-凝胶法;多孔二氧化硅;超细粉体
Key words：sol-gel process; porous silica; ultrafine powder
摘 要：以水玻璃为原料,乙酸乙酯为潜伏酸试剂,用溶胶-凝胶法制备了多孔SiO2超细粉体.对乙酸乙酯作为潜伏酸试剂的特点及反应温度和乙酸乙酯用量对硅酸盐聚合形成溶胶和凝胶过程的影响进行了分析和讨论.并用TG-DTA,XRD,TEM,IR和氮气吸附对粉体的基本性能进行了测试表征.结果表明,反应温度和乙酸乙酯用量对成溶胶和凝胶的时间有较大影响,在反应温度30℃、乙酸乙酯与SiO2摩尔比为0.65时,可制得粒径为10~20 nm的多孔SiO2超细粉体,粉体的BET比表面积为414 m2/g,孔形状为管状毛细孔,孔径主要在10~100 nm范围.
Abstract: Porous silica ultrafine powders were prepared by sol-gel method and n-butanol azeotropic distillation process from water glass using ethyl acetate as a latent acidic reagent.The products were characterized by TG-DTA,XRD,TEM,IR and nitrogen adsorption.The characteristic of polymerization of silicates to form silica sol and aggregation of silica colloid particles into silica gel in the presence of ethyl acetate was discussed and the effect of reacting temperature and amount of ethyl acetate added on the solgel process was investigated.The experiment results show that reacting temperature and amount of ethyl acetate added have significant influence on sol-gel formation time.Under the conditions of reacting temperature 30℃and mole ratio of ethyl acetate to silica 0.65,porous silica ultrafine powders,with particle diameter in the range 10 to 20 nm,BET specific surface area 414 m2/g,and pore size distribution between 10 and 100 nm,can be obtained.
