水熱条件下におけるセピオライトの相変化について

概要

論文の詳細を見る
Phase transformations of sepiolite under hydrothermal conditions were investigated by treatment of two varieties of sepiolite (α- and β-type) in the temperature range from 150° to 700℃ at water vapor pressures of 250, 500 and 1000kg/cm^2, respectively. The products were examined by means of X-ray diffraction technique, thermal analysis and infrared absorption spectroscopy. The results obtained are as follows : Under water vapor pressures of 500kg/cm^2 α-sepiolite is stable below 330℃. Above this temperature, it transforms into "hydrated talc" (330°~460℃) and talc (>460℃) β-sepiolite changes into "hydrated talc" (310°~530℃) and talc (>530℃). Therefore, it was found that an intermediate phase such as "hydrated talc" comes between sepiolite and talc in their stability fields. It seems that the revealed difference of the two sepiolites depends on the difference of their crystallinity and their length of fibers.
日本粘土学会の論文
1974-03-25