[3I01-05] Recovery of Cesium

[3I05] Examination of the siloxane-bond technology to reduce Fukusima-Daiichi NPP environment risk

Decontamination effect confirmation experiment

*Yoko Iwamiya¹, Masayoshi Kawai^1,2 (1. Choetsu Glass Chemistry Research Co. Ltd., 2. High Energy Accelerator Research Organization)

Keywords:Fukushima, radiation, cesium, Sol-Gel method, siloxan bond, decontamination, Watari elementary school, reactor decommissioning, radioactive waste, environment contamination

After East Japan great earthquake disaster, decontamination of radioactive cesium in the environment around the Fukusima-Daiichi NPP was of an urgent problem. The transcendence glass produced by the sol-gel method can be combined with both inorganic and organic materials by a siloxane bond. When one sprays a solution on the surface of the contaminated soil, the solution deeply penetrates into the slit in the soil according to the surface tension and makes cesium-adsorbed solid layer. The solidification layer is teared off easily and cesium in the ground is effectively removed. In May, 2011, we made the decontamination experiments at Watari Elementary School in Fukushima-shi. After tearing off the solidification layer, the reduction rate of dose on the ground was turned to be 70% in maximum in case of 17 mm solidification layer. It can be concluded that the solution will be effective to decrease environmental contamination problems by spraying in advance against radioactive dust migration in the future NPP decommissioning works as well as to reduce both environment dose rate and radioactive waste soil in decontamination works.