An Innovative valency control technique for actinides; Redox reactions of actinides induced by external ultrasound irradiation

Toraishi, Takashi; Kimura, Takaumi ; Arisaka, Makoto 

The chemical reaction induced by an ultrasound irradiation, which is the so-called sonochemistry, will be a promising alternative for the atomic valency control for actinides. The reductive/oxidative radicals, which is the result of the collapse of microbubles produced by an ultrasound irradiation to water, acts as a strong reductant or oxidant. Here, the reduction of hexavalent uranium is presented as a representative case. The test solution containing 5 mM UO(ClO) in 1 M HCl was irradiated by a 600 kHz external ultrasound. The Pt black catalyst was put into the sample. The solution was continuously bubbled with Ar gas, which was saturated with 2-propanol. After the ultrasound irradiation for some time period, the reduction of U(VI) was successfully confirmed from the UV-VIS spectra. As it is demonstrated in this representative case, the ultrasound irradiation will be a very promising technique for the valency control of actinides.