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Arai, Yoichi; Watanabe, So; Hasegawa, Kenta; Okamura, Nobuo; Watanabe, Masayuki; Takeda, Keisuke*; Fukumoto, Hiroki*; Ago, Tomohiro*; Hagura, Naoto*; Tsukahara, Takehiko*
Nuclear Instruments and Methods in Physics Research B, 542, p.206 - 213, 2023/09
Times Cited Count：1 Percentile：0.02(Instruments & Instrumentation)
solution; Comparison with tri-
-butyl phosphateUeda, Yuki; Kikuchi, Kei; Sugita, Tsuyoshi; Motokawa, Ryuhei
Solvent Extraction and Ion Exchange, 37(5), p.347 - 359, 2019/07
Times Cited Count：8 Percentile：34.18(Chemistry, Multidisciplinary)We have newly-designed fluorous phosphate(TFP) for the effective Zr(IV) ion extractant as an alternative extractant against the conventional organic phosphate, tri--butyl phosphate(TBP). Zr(IV) ion extraction system using the TBP has many problems such as the formation of the third phase during liquid-liquid extraction. Here, we develop the fluorous extraction system based on the TFP-perfluorohexane for the Zr(IV) ion extraction to improve the Zr(IV) ion extraction system with an effective extractability and without the third phase formation. Our main findings were that the significant high extraction performance of the TFP for Zr(IV) ion as compared with TBP, and the origins of the high extraction performance of the TFP are related to the water and HNO contents in the fluorous phase and the stability of the complex, Zr(No)
(TFP).
Motokawa, Ryuhei; Endo, Hitoshi*; Nagao, Michihiro*; Heller, W. T.*
Solvent Extraction and Ion Exchange, 34(5), p.399 - 406, 2016/07
Times Cited Count：5 Percentile：19.64(Chemistry, Multidisciplinary)-butyl phosphate in organic and aqueous environments and its relevance to nuclear extraction processesMu, J.*; Motokawa, Ryuhei; Williams, C. D.*; Akutsu, Kazuhiro*; Nishitsuji, Shotaro*; Masters, A. J.*
Journal of Physical Chemistry B, 120(23), p.5183 - 5193, 2016/06
Times Cited Count：27 Percentile：60.26(Chemistry, Physical)Tachimori, Shoichi
JAERI 1337, 250 Pages, 1996/05
no abstracts in English
Asakura, Toshihide; ; Uchiyama, Gunzo; Fujine, Sachio; Maeda, Mitsuru
JAERI-Tech 95-027, 34 Pages, 1995/03
no abstracts in English
Sakurai, Satoshi; Abe, Hitoshi; Tachimori, Shoichi
Journal of Nuclear Science and Technology, 29(1), p.86 - 89, 1992/01
no abstracts in English
; Miyoshi, Yoshinori; Tachimori, Shoichi
JAERI-M 91-184, 31 Pages, 1991/11
no abstracts in English
Kusaka, Ryoji; Watanabe, Masayuki
no journal, ,
The solvent extraction utilizing the complex formation between uranyl and tributyl phosphate (TBP) is important as a method for treating spent nuclear fuel. Since TBP is surface active, it is believed that the uranyl-TBP complex is formed at the organic/TBP/water interface, and the complex is extracted into the organic phase. However, the structure of the uranyl-TBP complex formed at the interface is controversial. In this study, the structure of the uranyl-TBP complex was investigated by heterodyne-detected vibrational sum frequency generation spectroscopy at the surface of an aqueous solution of uranyl and TBP (TBP molecular layer/aqueous solution interface). Surprisingly, it is found that uranyl-TBP complex does not form at the interface.
Ono, Shimpei; Arai, Yoichi; Watanabe, So; Seko, Noriaki*; Kasai, Noboru*; Hoshina, Hiroyuki*; Shibata, Atsuhiro; Nomura, Kazunori
no journal, ,
no abstracts in English
Kusaka, Ryoji; Watanabe, Masayuki
no journal, ,
Liquid-liquid solvent extraction of uranyl using tributyl phosphate (TBP) is a significantly important technique in treatments of spent nuclear fuels. In the solvent extraction, TBP comes to an organic/aqueous interface and forms an organic/TBP monolayer/aqueous interface because of the surface activity of TBP. At the interface, it is believed that the complex formation between uranyl and TBP takes place, and subsequently the uranyl-TBP complex transfers to an organic phase. However, the structure of the uranyl-TBP complex formed at the interface is controversial. This is partly because of no experimental studies on molecular-level structure at interfaces pertaining to the solvent extraction of uranyl. Recently, we proposed that an extractant/aqueous interface, formed on the surface of an aqueous solution, is a good model of an organic/extractant/aqueous interface, to investigate the structure of interfacial metal complexes using vibrational sum frequency generation (VSFG) spectroscopy. In the present study, we investigated the structure of theuranyl-TBP complex at the TBP/uranyl aqueous solution interface by VSFG spectroscopy. Surprisingly, interface-selective vibrational spectra obtained by VSFG suggests that uranyl does not form a complex with TBP at the TBP/uranyl aqueous solution interface. This result proposes that we should reconsider the mechanism of the solvent extraction of uranyl by TBP.
solution; Comparison with tri--butyl phosphateUeda, Yuki; Kikuchi, Kei; Sugita, Tsuyoshi; Tokunaga, Kohei; Motokawa, Ryuhei; Naganawa, Hirochika
no journal, ,
The extraction and separation of Zr(IV) as a major fission product from aqueous HNO solutions have been investigated extensively because the presence of Zr in the TBP-based PUREX process for reprocessing spent nuclear fuel is problematic. Moreover, the formation of liquid-liquid (water, oil) interfacial cruds or a third phase during Zr extraction by TBP from HNO aqueous solution occurs with a high metal loading in the organic phase. In this study, we develop a fluoroalkylated phosphate (TFP) for Zr(IV) extraction to increase the extractability and prevent third-phase formation. We investigated the extraction performance and mechanism of TFP extraction of Zr(IV) from HNO solutions into perfluorohexane and compared them with the conventional organic extraction system using TBP in n-octane. The Zr(IV) extraction strength of TFP in the fluorinated diluent perfluorohexane was much higher than that of TBP in n-octane.
Kikuchi, Kei; Ueda, Yuki; Sugita, Tsuyoshi; Naganawa, Hirochika
no journal, ,
Fluorous solvents, such as perfluorinated alkanes, ethers, and tertiary amines have excellent chemical properties, including low toxicity, low viscosity, nonflammability, chemical stability, and immiscibility with both water and organic solutions. However, there are few reports on metal ion extraction in fluorous biphasic systems, because hardly any extractants that have a high affinity for fluorous solvents and the introduction of fluorous groups can reduce the extraction performance. In this study, a fluorous extractant with a sufficiently long spacer between the coordinating group and fluoroalkyl chain can maintain the original coordinating ability, which is comparable with a conventional organic extractant, and have an affinity for the fluorous solvent. We investigated the extraction performance and mechanism of TFP extraction of Zr(IV) from HNO solutions into perfluorohexane and compared them with the conventional organic extraction system using TBP in n-octane.
Iwamoto, Hibiki*; Sato, Hiromori*; Arai, Tsuyoshi*; Watanabe, So; Sano, Yuichi
no journal, ,
We investigated the effects of nitric acid, TBP and salting out reagent concentrations on the rare earth element (Ln (III)) extraction using TBP, which is inexpensive and has selective extractability. It was suggested that Ln (III) can be extracted by controlling the nitric acid and nitrate ion concentrations.
Arai, Yoichi; Watanabe, So; Hasegawa, Kenta; Okamura, Nobuo; Watanabe, Masayuki; Takeda, Keisuke*; Fukumoto, Hiroki*; Ago, Tomohiro*; Hagura, Naoto*; Tsukahara, Takehiko*
no journal, ,
solution; Comparison with a conventional organic phosphateUeda, Yuki; Micheau, C.; Tokunaga, Kohei; Sugita, Tsuyoshi; Akutsu, Kazuhiro*; Motokawa, Ryuhei
no journal, ,
