Studies on factors for controlling phase separation of ionic liquid with thermomorphic behavior and application to the decontamination treatment of uranium wastes

2014 Fiscal Year Final Research Report

• Project/Area Number: 24360390
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Nuclear engineering
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: HARADA Masayuki 東京工業大学, 原子炉工学研究所, 助教 (60133120)
• Co-Investigator(Kenkyū-buntansha): IKEDA Yasuhisa 東京工業大学, 原子炉工学研究所, 教授 (40323836)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: イオン液体 / 熱応答性 / 相分離 / ベタイン / ウラニルイオン / 抽出 / ウラン汚染物 / 除染

Outline of Final Research Achievements

Factor for controlling phase separation of ionic liquid [Hbet][Tf2N] (Hbet: 1-carboxy-N, N, N-trimethyl- methanaminium hydroxide, Tf2N bis (trifluoromethylsulfonyl)imide) with thermomorphic behavior has been studied. So far, the phase separation has been considered to be due to the dissolution of Hbet with the deprotonation from the results of nuclear magnetic resonance, Raman emission, near infrared spectroscopy, and this proposal has been supported by molecular dynamics. However, the present study clarified that the phase separation is due to the incorporation of water and [Hbet][Tf2N] with the formation of hydrogen bond network.
Furthermore, separation of uranyl ion utilizing the phase separation phenomenon was studied. As a result, it was found that the uranyl species are extracted with high efficiency (extractability: ca. 100 %) from nitric acid aqueous solutions of relatively low concentrations and that this separation is due to the complexation of the betaine to the uranyl ion.

Free Research Field

無機化学