カオリナイトからクリストバライトの生成におよぼす吸着-価陽イオンの影響

概要

論文の詳細を見る
The rate of cristobalite formation from a kaolinite saturated with some monovalent cations was studied comparing with the crystallization nature of some amorphous silica, i.e. precipitated-, thermally decomposed-silica gels, and powdered silica glass, to which 1-2 mol% of alkali carbonates had previously been added. The results obtained are summarized as follows. 1) The adsorbed cations controlled the nucleation period of cristobalite formation and the Li ion was the most powerful accelerator for the nucleation. 2) The nature of crystallization from the silica gels resembled closely to that of the cristobalite formation from the kaolinite except that quartz phase appeared from Li containing-silica gels. 3) The crystallization from the kaolinite and the silica gels could be considered as homogeneous nucleation process by reason of the linear growth rate and of that the alkali ions would had been intimately distributed throughout the very fine amorphous silica particles. 4) The aspect of crystallization from the coarsely powdered silica glass differed quitely from those of the kaolinite and the silica gels, i.e. Li ion retarded the crystallization and the process could be considered as heterogeneous nucleation.
社団法人日本セラミックス協会の論文
1973-01-01