Gas-Flow Resistance in Continuous Macropores in Silica Rods Prepared by Freezing Transitional Structures of Phase Separation
Gas-Flow Resistance in Continuous Macropores in Silica Rods Prepared by Freezing Transitional Structures of Phase Separation
复制标题
冷冻相分离过渡结构制备石英棒连续大孔的气体流动阻力
DOI：
10.2109/jcersj.112.99
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发表时间：
2004
影响因子：
1.1
通讯作者：
H. Nishino
中科院分区：
文献类型：
--
作者：
Ryōji Takahashi;S. Sato;T. Sodesawa;Akihiro Haga;H. Nishino
研究了气体在硅胶棒三维连通大孔中流动的压力损失。在硅胶的制备中，通过在含有四乙氧基硅烷（TEOS）和聚（环氧乙烷）（PEO）的溶液中诱导相分离，并随后通过凝胶化使其过渡结构冻结来形成连续大孔。通过改变溶液中PEO的含量，在不影响多孔结构的情况下，系统地控制了硅胶的平均大孔径在25 ~ 0.6 μm之间。连续大孔中气流的压力损失可以用简单的直通道模型来近似，并且可以用Hargen-Poiffille方程很好地再现而无需任何校正，与填充有微米尺寸颗粒的柱中的压力损失相反，其显示出比连续大孔高得多的压力损失。大孔二氧化硅棒中的低流动阻力将归因于流动路径中不存在颈。
Pressure loss in gas flow in three-dimensionally interconnected macropores in silica gel rods was investigated. In the preparation of the silica gel, the continuous macropores are formed by inducing phase separation in a solution containing tetraethoxysilane (TEOS) and poly (ethylene oxide) (PEO), and subsequent freezing of its transitional structures by gelation. Average macropore size of the silica gels was systematically controlled from 25 to 0.6 μm by changing PEO content in the solution without affecting porous morphology. The pressure loss in gas flow in the continuous macropores can be approximated with a simple straight channels model, and well reproduced with the Hargen–Poiseuille’s equation without any correction, in contrast to that in columns packed with micrometer-size particles, which show substantial higher pressure loss than the continuous macropores. The low flow resistance in the macroporous silica rods would be attributed to the absence of necks in flow pathways.