陽イオン交換モンモリロナイトの加熱生成物

抄録

Montmorillonite has been classified into Cheto-type and Wyoming-type, on the basis of their heating products. In order to test the validity of this criterion, montmorillonite samples were exchanged with various cations such as Na, K, Ca, and Mg ions, and their heating products were examined. It is easily confirmed that (1) Mg and Ca ions added are very effective for the formation of high quartz phase, (2) Na and Mg ions are effective for the formation of cristobalite phase, and (3) K ion is effective for the formation of spinel phase. Changes in X-ray powder pattern with heating temperatures suggest that high quartz phases formed are a kind of solid solutions, MgO-SiO₂-Al₂O₃ or CaO-SiO₂-Al₂O₃. All the results obtained show that the heating products do not depend on the characteristics of constituting layer sheets, but those of exchangeable interlayer cations. A factor analysis was also applied to estimate quantitatively the individual effect of cations including alkali metal, alkali earth metal and transition metal ions for the formation of various phases.