X-RAY STUDIES OF REHYDRATION BEHAVIORS FOR MONTMORILLONITE

概要

論文の詳細を見る
The rehydration properties for Ca-, Mg-, Na- and K-saturated montmorillonites after heating at various temperatures were examined and positions of interlayer cations for unheated, dehydrated and rehydrated specimens were investigated by means of one-dimensional Fourier analysis. Mg-saturated specimen dehydrated irreversibly after heating at 400℃, while rehydration was recognized after heating at 600℃ for Ca- and Na-saturated specimens and at 700℃ for K-saturated specimen. After heating at 600℃ for the Na-saturated specimen, the interlayer cations (Na^+) migrated into shallow part of the hexagonal holes, and the heated specimen restored its original hydrated configuration of interlayer region after water saturation. In the case of after heating at 800℃, the interlayer cations (Na^+) migrated into deep part of the holes, and drehydration did not occur even after water saturation. These results are due to the fixation of interlayer cations (Na^+) to the hexagonal holes of SiO_4 network after heating at 800℃, and it becomes difficult to extract these fixed cations from the holes. Therefore, the migrated positions of interlayer cations play an important role in its rehydration properties.
日本粘土学会の論文