抄録
Cesium (Cs) sorption experiments were conducted using the soil of a paddy field in Fukushima, Japan, to find Cs-sorbing materials in the actual soil. The soil particles were reacted with a CsCl solution for one day, which formed a Cs concentration in the soil particles of around 150 ppm. The Cs-sorbed particles were molded into the form of a disk and Cs distribution on the disk surface was acquired using electron-probe X-ray microanalysis. The Cs-concentrated regions on the disk were further confirmed using scanning electron microscopy, and thin film specimens for transmission electron microscopy (TEM) were prepared using a focused-ion-beam instrument. TEM with X-ray microanalysis revealed that the major Cs-sorbing materials were biotite-vermiculite (B-V) mixed-layer mineral and aluminous smectite containing considerable amounts of iron. The B-V mixed layer mineral incorporated cesium ions at the interlayer regions which were probably originally hydrated ones. The structure and Cs-adsorption/desorption properties of the smectite should be investigated in future.
