| 摘要 |
PROBLEM TO BE SOLVED: To efficiently obtain a hollow spherical silicate cluster which is homogeneous and excellent in water, heat and corrosion resistances by using a high- concn. starting material, by simultaneously and rapidly mixing a silicon compd. soln. and an aluminum compd. or transition metal compd. soln. each having specified concn., then removing salt as a by-product and successively carrying out hydrothermal synthesis. SOLUTION: A silicon compd. soln. and a soln. of aluminum compd. or transition metal compd. each having 10 to 1000mmol concn. of the soln. are simultaneously or rapidly mixed at 1 to 10000ml/min mixing rate. After the salt as a by-product is removed, the mixture is subjected to hydrothermal synthesis. In this process, the molar ratio of silicon/aluminum or transition metal compd. is preferably 0.5 to 5.0. The silicate spherical particles which from a cluster have 1 to 10nm average particle size and about 50 to 500m<2> /g specific surface are measured by a nitrogen absorption method. The salt is removed by ultrafiltration, centrifugal separation, etc. |
