The massive tsunami generated by the Great East Japan Earthquake caused a nuclear power plant accident that the world has never experienced before. The radioactivity-contaminated water is being re-circulated as a coolant for the damaged nuclear fuel after adsorption removal of nuclides using zeolites, as well as desalination using a reverse osmotic membrane. However, radioactive nuclides such as Cs- and Sr-adsorbed zeolites are generated as radioactive waste due to these adsorption treatment methods for radioactivity-contaminated water that goes-through the process one. Therefore, we have focused on ion exchange chromatography using a strongly acidic inorganic-organic composite type cation exchanger (SiSCR), which has superior ability in adsorption/elution speed, in this research. In this research, it was found that the selectinity of SiSCR was Sr(II)>Ca(II)>Mg(II)>Fe(II)>Ni(II)>Cs(I)>K(I)>Na(I). It was then confirmed that the equilibrium time was less than one minute. Moreover, we have been measuring adsorption, elution and separation behavior of alkali and alkaline-earth metal ions included in the radioactivity-contaminated water for SiSCR. It was found that the SiSCR-packed column was superior in ability to the commercial cation exchange resin in terms of dynamic adsorption/elution characteristics. In particular, it was shown that the separation of Ca(II) and Sr(II) was effective using the SiSCR packed column.

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 Ion exchange from K_0.8Zn_0.4Ti_1.6O₄ to protonated compound while avoiding the dissolution of the Zn element succeeded was successful when NH₄NO₃ molten salt solvent was used. Based on FT-IR measurements and chemical analysis, it was thought that the ion-exchange compound changed to (NH₄, H₃O)_0.87K_0.03Zn_0.35Ti_1.6O₄. Furthermore, the ion-exchange compound showed through chemical analysis data and x-ray diffraction data that the Zn element remained in the crystal structure at various sintering temperatures.

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