高品质稻壳基二氧化硅的制备新工艺

A New Process for the Preparation of High-quality SiO_2 from Rice Husk Ash

本文报道了以稻壳灰和碳酸钠为原料,具有酸性和表面活性的2-丙烯酰胺-2-甲基丙磺酸溶液(2-Acrylamido-2-methylpropane sulfonic acid,AMPS)为沉淀剂和分散剂,经化学沉淀法制备高品质稻壳基二氧化硅的新工艺。并采用ICP光谱仪、X射线衍射仪、傅立叶红外光谱、扫描电镜、低温氮吸附法等对产物的杂质含量、结构、形貌特征及多孔特性进行了表征确证。获得了适宜的制备工艺条件为,0.2 mol/L硅酸钠溶液与25%的AMPS溶液以1∶2质量比混合,反应温度40℃,滴加速度0.05 ml/s,滴加完后静置3h,在此条件下,二氧化硅的产率为99%,所得产物的形貌近微球结构,平均粒径为100 nm,孔径32 nm,比表面积205 m2/g,二氧化硅含量达99.0%,可作为优良的轮胎补强剂等使用,本研究结果为稻壳灰的高质化利用提供了新途径。

A new process for the preparation of high-quality SiO2 from Rice Husk Ash was reported with rice husk ash and Na2CO3 as raw materials and AMPS as precipitant and dispersant.Morphology,microstructure and properties of the synthesized particles were characterized by ICP,X-ray diffraction(XRD),FT-IR analysis,SEM analysis.The suitable reaction condition is obtained as follows:at 40℃,mass ratio of 25%AMPS solution to 0.2 mol/L Na2SiO3 was 2∶1,dropping speed of AMPS solution 0.05 mL/s,after the addition,the system rests for 3h.Under these conditions,the yield of silica is 99%,the morphology of the product is near microsphere structure,the average particle size is 100 nm,the pore size is 32 nm,the specific surface area is 205 m2/g,and the silica content is 99.0%.It can be used as a high-class reinforcing agent for tires which provides a new way to the efficient utilization of rice husk ash.