超重力反应沉淀法制备超细二氧化硅

Preparation of ultrafine SiO_(2 ) powders by high gravity reactive precipitation method

以水玻璃和硫酸为原料,采用超重力反应沉淀法合成了超细二氧化硅粉体。研究表明:与传统搅拌槽反应器相比,在超重力反应器内,二氧化硅沉淀反应的时间可大大缩短(缩短至10 m in以内);通过产品分析测试发现,所得到的二氧化硅产品具有粒径小(<20 nm)、粒度均匀、比表面积大、孔径分布较窄等特点,并具备能提高与高分子材料的相互作用的中大孔结构。

Ultrafine SiO2 powders were prepared by High Gravity Reactive Precipitation method from water glass solutions and sulphuric acid. Experimental results revealed that in high gravity reactor the reaction time shortened enormously compared with that in conventional stirred tank reactor（ the reaction time in High Gravity Reactor 〈 10 min）. Through characterization by XRD,IR,TG - DTA,TEM and BET etc.. The results indicate that the prepared SiO2 has uniform particle size with less than 20 nm, very narrow size distribution and high specific surface area, and also has mesoporous and macroporous structure which make it easy to combine with macromolecule materials.