- A comparative study of drying techniques on the morphology of porous silica gels synthesized via sol-gel process
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- 论文类型： 期刊论文
- 发表时间： 2011-08-01
- 发表刊物： Journal of Harbin Institute of Technology (New Series)
- 收录刊物： EI、Scopus
- 卷号： 18
- 期号： 4
- 页面范围： 71-76
- ISSN号： 10059113
- 摘要： The effect of drying techniques on the microstructure, morphology and pore structure of porous silica gels was studied in the paper. The gels were prepared by using sol-gel process and different drying routes: freeze-drying (FD), low pressure drying (LPD), high temperature drying (HTD) and chemical modification & ambient drying (CMD) techniques. Observation under pore distribution and structural properties showed that CMD technique leads to homogenous mesoporous silica material with specific surface area of 745 m2/g, and the average pore size around 20 nm, while LPD and HTD result in loosely packed particles with non-isotropic aggregation pattern. The specific surface areas of LPD and HTD samples are 419 and 513 m2/g respectively, and the pore size distribution of the samples are observed distributing widely in range of 10-100 nm. Freeze drying method is a new but prospective way to prepare mesoporous silica. The specific area of FD sample is around 500 m2/g. By the comparison for the properties of the gels, this paper wants to induce a further interest in finding a proper method to synthesize the porous silica gels for low price use.
