球形二氧化硅微粉制备新工艺

Research on the new process for the preparation of Silica micro-spheres

以硅酸钠为原料,乙酸乙酯为沉淀剂,无水乙醇为分散剂,复配型表面活性剂为结构调控剂,常温反应制备球形二氧化硅微粉的新工艺。确定了反应过程条件的变化对产物二氧化硅粉末形貌及产率的影响规律;得到最佳的制备工艺条件:硅酸钠浓度为0.6mol/L,复配型表面活性剂PEG-1000和SDBS(质量比为20∶1)的总用量为原料质量的2.1%,无水乙醇用量为原料质量的5.0%,乙酸乙酯用量为原料质量的8.0%,搅拌速度600r/min,反应时间4.0h,在此条件下,得到了平均粒径400nm的球形二氧化硅微粉,最高产率93.8%。利用红外光谱、扫描电镜和X射线粉末衍射对产物进行了分析确证。

Silica micro spheres were prepared from sodium silicate at room temperature with ethyl acetate as the precipitant. The influence of reaction parameters on the morphology and the yield of SiO2 powders was systematically investigated, and the optimum reaction condition was confirmed as follows, the concentration of sodium silicate was 0.6 mol/L, the total amount of the blend surfaetants with PEG-1000 and SDBS was 2.1 % and the blend ratio was 20 ： 1, the amount of the dispersant with ethanol and the precipitant with ethyl acetate were 5.0% and 8.0%, respectively, the stirring rate was 600 r/min and the reaction time was 4 hours, the average particle size was 400 nm without obvious agglomeration and the yield was 93. 8% . The product was characterized and confirmed by Infrared Spectroscopy, Scanning electron microscope, and X ray powder diffraction analysis.