Sorption behavior of Am onto bentonite colloid

Iijima, Kazuki  ; Shoji, Yoshiyuki; Tomura, Tsutomu*

Sorption behavior of Am onto bentonite colloid was investigated. Distribution coefficient of Am was evaluated taking account for the existence of Am colloid. Obtained values were larger than those obtained with larger bentonite particles included in the JNC-SDB. In the acid-base titration, bentonite colloid shows larger edge site density than larger bentonite particles. In the calculation by sorption model assuming ion exchange and surface complexation, similar distribution coefficient was obtained at pH 8 with this edge site density. Based on these results, it is considered that larger distribution coefficient of bentonite colloid is due to the higher edge site density, which is dominant for the Am sorption.