Distribution coefficients of radio-elements on compacted bentonite under cementitious conditions

Mine, Tatsuya*; Mihara, Morihiro  ; Kato, Hiroshige*

It is important to obtain the distribution coefficients of radio-elements on the bentonite under cementitious conditions in the geological disposal system of radioactive wastes. In-Diffusion experiments of Cs, Sr, Zr, Nb, Ni, Sn, Am, U, Np in Na-bentonite, Ca-bentonite, bentonite analcite mixture were carried out and the distribution coefficients were calculated. The experimental parameters were dry density (1200kg/m, 1600kg/m, 1800kg/m$^) and synthetic solution type (distilled water, cementitous solution, cementitious solution+sea water, cementitous solution+sea water+nitrate). It was shown that the effects of the experimental parameters on the distribution coefficients on the most part of radio-elements used in this study were relatively small.