Photocatalytic unification of iodine species using platinum-loaded titanium dioxide

Sugita, Tsuyoshi   ; Mori, Masanobu*; Kozai, Naofumi   

Removal of iodine from water contaminated by nuclear accidents or the release of radioactive waste is complicated and costly because iodine exists in a variety of forms in the water. We investigated the unification of iodine species by photocatalysis as a pretreatment for removing radioactive iodine species from water. The effect of the TiO crystal phase of Pt-TiO and solution pH on the photocatalytic redox reactions of iodide (I), iodate (IO), and -iodobenzoic acid were evaluated. The choice of TiO crystalline phase and pH allowed the mixture of iodine species to be unified to only I or IO. Regardless of the type of Pt-TiO, the iodine in o-iodobenzoic acid was mineralized to I under alkaline conditions. Because the iodine species can be unified to a single species by selecting the photocatalyst and the solution pH, this photocatalytic treatment could be applied to remove iodine species with high efficiency.