Improvement and evaluation of titanosilicates for radioactive waste processing materials - Looking ahead to the future of Fukushima -

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K06927
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Earth system and resources engineering
• Research Institution: Yamaguchi University
• Principal Investigator: FUJIWARA keiko 山口大学, 大学院創成科学研究科, 助手 (50253175)
• Co-Investigator(Kenkyū-buntansha): 中塚 晃彦 山口大学, 大学院創成科学研究科, 准教授 (80294651)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: マイクロポーラス / 放射性物質 / 汚染水 / イオン交換 / サマリウム / ニッケル / エルビウム

Outline of Final Research Achievements

Ion-exchange properties of Na-GTS type of titanosilicates in order to removing a long radioisotope of the half-life from the radioactive waste water appropriately have been investigated.
It showed the maximum ion exchange rate of each cation-exchanged forms is Sm: 100%, Er: 98%, Ni:85% which were shaked of Na-GTS in the aqueous solutions of chloride (0.01～0.5M) from 25 to 60 ℃ for 24 hours.
By Er3+ exchange, the water content decreased and by Ni2+ exchange, the water content increased. The increase in the Sm3+ and Er3+ exchange rate decrease the unit-cell volume V. The increase in the Ni2+ exchange rate increased the unit-cell volume V. The simulation of XRD patterns suggests the cation-distribution model that Sm, Er and Ni ions preferentially occupy almost equally on the 4e and 6g sites in the GTS cavity.

Free Research Field

無機材料および物性関連

Academic Significance and Societal Importance of the Research Achievements

福島第一原子力発電所の汚染水から半減期の長い放射性同位体を除去するため、Na-GTS型チタノシリケート（Na-GTS）のイオン交換特性を調べた。Sm3+, Er3+およびNi2+については、GTSの結晶構造を保った状態で、最大許容量である交換率に近い値をもつ交換体を得た。従って、Na-GTSは増え続ける汚染水に含まれる半減期の長い放射性物質を吸着する材料として有望であると思われる。