Pulse-radiolysis study on effect of water-silica interface on radiation-induced reactions

Kumagai, Yuta   ; Nagaishi, Ryuji ; Yamada, Reiji; Muroya, Yusa*; Katsumura, Yosuke*

Reactions of the radiolytic products of water in aqueous solution of colloidal silica have been studied by pulse-radiolysis technique in order to understand the effect of interface between ceramic oxides and water on radiation-induced reactions in aqueous solution, which is important in connection with the radiation effect on groundwater in the geological disposal of high-level radioactive waste. Time-resolved measurement on the reaction of OH radical with ferrocyanide ion in the presence of colloidal silica indicates that the colloidal silica reacts with OH radical in competition with ferrocyanide ion. The measured reactivity of colloidal silica toward OH radical was approximately proportional to its surface area and also depended on the pH of aqueous solution.