粘土鉱物結晶水の加熱による赤外線吸収スペクトルの変化-特に500-550cm-1の吸収について
1962 年 70 巻 796 号 p. 81-89
詳細
1962 年 70 巻 796 号 p. 81-89
The relation between the change of infrared spectra in 450-550cm-1 (22.2-18.2μ) and 900-1000cm-1 (11.1-10.0μ), and the change of structure by rehydration of pyrophyllite, montmorillonite, illite, kaolinite, halloysite and muscovite were studied.
The samples were dehydrated by heating, respectively, at 250°, 600°, and 1050°C for an hour. Some of them were rehydrated by keeping in air or in water, and also by hydrothermal treatment (300°C, 85atm., 1-10hrs.).
The results obtained are as follows:
(1) The absorption in the wave numbers 520-540cm-1 remained unaffected by the dehydration at 250°C, whereas it disappeared after the removal of lattice water by heating at a temperature higher than 600°C.
The spectra did not come into existence again by the rehydration by keeping in air, or in water, but appeared again by hydrothermal treatment (300°C, 85atm., 1-10hrs). It seems, therefore, that the absorption is closely related with the water of crystallization, and probably the water in the lattice is held strongly by hydrogen bond.
(2) The absorption in 900-1000cm-1 (11.1-10.0μ) which disappeared by the removal of the water of crystallization did not appeared by rehydration by keeping in air, or in water, but appeared again by hydrothermal treatment.
It was confirmed by hydrothermal treatment that the spectra were based on the OH in lattice combining to Al in the octahedral layer of clay minerals.
(3) The absorption in 460-470cm-1 (21.2-21.7μ), comming from Si-O bond, changed as the sliding down of the base line by the removal of lattice water, and recovered again by the hydrothermal treatment.
