Silica gel with large pore volume,high specific surface area,and more uniform particle size distribution was prepared by supercritical carbon dioxide drying method when silica hydrogel was soaked in ethanol solution (volume ratio 1: 10). The results showed that the silica gel with specific surface area 444.6 m2/g, pore volume 3. 124 cm3/g and average pore diameter 28.10 nm could be prepared at mass fraction of ethanol 90％ , carbon dioxide in reactor pressure 15.0 MPa,carbon dioxide replacement time 2.5 h.%将硅水凝胶置于乙醇水溶液(二者体积比为1∶10)中,采用超临界二氧化碳干燥的方法可以制备大孔容、高比表面积、粒径分布较为均匀的硅胶试样.结果表明,在乙醇水溶液质量分数为90%,反应器二氧化碳压力为15.0 MPa,置换时间为2.5 h的条件下,可制备比表面积为444.6 m2/g,孔容为3.124 cm3/g,平均孔径为28.10 nm的硅胶.
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