一种高纯度大孔硅胶的制备工艺

Preparation process of a high purity macroporous silica gel

以硅酸盐、无机酸为原料,经凝胶、老化、酸化、水洗、除杂、干燥工序后得到高纯度大孔硅胶,用比表面空隙仪对样品的物性参数进行了分析,用X-荧光分析仪对样品中的SiO2和杂质含量进行了测定。结果表明,将所选用的除杂剂加入常规工艺制得的硅胶滤饼中,在水浴温度为60℃、搅拌时间为1 h的条件下,可以得到孔容为1.5～2.0 mL/g、孔径为18～25 nm、比表面积为260～350 m2/g、纯度为99.5%以上的高纯度大孔硅胶。

A high purity macroporous silica gel was prepared with mineral acid and silicate as raw materials by gelling,aging,acidification,washing,purification and dehydration.The surface area,pore volume and pore diameter of samples were characterized by BET,the content of SiO2 and impurities were measured by X-luminoscope.The results showed that high purity macroporous silica gel with a content of SiO2 more than 99.5%,pore volume 1.5—2.0 mL/g,pore diameter 18～25 nm and specific surface area 260—350 m2/g could be prepared by adding impurities removal agent in silica gel filter cake prepared by conventional process at water bath temperature 60 ℃ and by stirring for an hour.