Radioactivity and Air Dose Rate
（2014）
ＱOn which minerals does radioactive Cs get adsorbed?
ＡWe investigated the absorption behavior of radioactive Cs on various minerals to find that Cs is selectively adsorbed onto weathered biotite.
Fig. 1 Read-out images of imaging plates with particles of various minerals onto which radioactive Cs was adsorbed
The read-out images of imaging plates (IPs) when a minute amount of radioactive Cs was absorbed onto various clay minerals (for the initialisms, see the table at the bottom right of the figure). The radioactivity input to the 137Cs solution and the reaction time are at the top and left, respectively. The figure at the top right of each image is the percentage of 137Cs adsorbed on all the mineral particles. These images show that the adsorbed radioactive Cs was concentrated on weathered biotite.
Fig.2 A model of radioactive-Cs adsorption onto weathered biotite
Weathered biotite has a layered structure. Several examples have been indicated, for example, radioactive Cs entered via a swollen layer called a frayed edge and was strongly fixed by the collapse of the layers when the radioactive Cs was absorbed.