| 摘要 |
PURPOSE:To provide a honeycomb silica having light weight per unit volume and high strength and containing fine pores in addition to honeycomb-like pores extending one-dimensionally in one direction. CONSTITUTION:A liquid containing a siliceous substance and having a silica concentration of 3-50wt.%, especially 5-50wt.% is produced by using a solvent separable and removable by freeze-drying (generally water) and is quickly frozen. The quick-freezing is carried out e.g., by dripping said silicate-containing liquid into a refrigerant such as liquefied gas of <=-50 deg.C (e.g., liquid N2) or trichlroethylene, etc., maintained at <=-50 deg.C. The objective honeycomb silica can be produced from the resultant cylindrical frozen material generally by vacuum drying while preventing the thawing of the material. The obtained honeycomb silica has cylindrical pores of 1-20mum diameter and further contains fine pores having diameter of usually <=0.1mum. The honeycomb silica is expected to be useful as a catalyst carrier, adsorbent, particular light-weight filler, porous structural material, etc.
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