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Esaka, Fumitaka; Yomogida, Takumi; Tomita, Ryohei; Miyamoto, Yutaka
no journal, ,
Chemical state analysis is important to elucidate the origin of particles and its effect on the environment. However, the analysis is difficult because the amounts of elements in individual particles are considerably small. In the present study, electron backscatter diffraction (EBSD) is applied to the chemical state analysis of individual uranium particles. As a result, uranium particles with diameters of 1
m were able to be measured and clear electron backscatter patterns were observed. In addition, the patterns of UO
particles were distinguished from those of U
O
particles.
Abe, Yuta; Nakagiri, Toshio; Sato, Ikken; Nakano, Natsuko*; Yamaguchi, Hidenobu*
no journal, ,
no abstracts in English
Kawakami, Tomohiko*; Abe, Yuta; Spaziani, F.*; Nakano, Natsuko*; Nakagiri, Toshio
no journal, ,
no abstracts in English
Asai, Shiho; Yomogida, Takumi
no journal, ,
Palladium found in spent nuclear fuel is characterized by having radiopalladium 
Pd (Half-life: 6.5
10
y). With its long half-life, accurate determination of the amount of Pd in spent nuclear fuel is essential for estimating the radiation effects. However, no experimentally determined concentration has been reported due to the difficulties in obtaining pure palladium form spent nuclear fuel with conventional separation techniques. In this study, Pd in spent nuclear fuel solution was separated by precipitation triggered by photoreduction of Pd(II) with pulsed laser irradiation. About 20 min of the irradiation to the spent nuclear fuel solution provides high Pd recovery of more than 90%. The prepared Pd precipitate was dissolved with aqua regia and measured with ICP-MS. Almost no impurities were detected in the Pd precipitate, resulting in the accurate determination of Pd.
Yomogida, Takumi; Asai, Shiho; Saeki, Morihisa*; Hanzawa, Yukiko; Horita, Takuma; Esaka, Fumitaka; Oba, Hironori*; Kitatsuji, Yoshihiro
no journal, ,
Recently, we developed a precipitation-based separation method for the determination of Pd with ICP-MS. However, a pulsed-laser light source is indispensable to form Pd precipitation in the separation method. There were difficulties in handling of a pulsed-laser light source. Simplified irradiation procedure is desirable to facilitate a Pd separation procedure. In this study, we developed a simple Pd separation technique based on photoreduction with Xe lamp irradiation and applied the technique to a simulated HLW solution. The Pd recovery from a simulated HLW solution reached 50%, while 99% of the other 13 elements were removed. These results indicate that selective separation of Pd is achieved with the simplified irradiation procedure.
Okamura, Hiroyuki
no journal, ,
The selective separation of lanthanoids by the synergistic ionic-liquid extraction with anionic chelating ligands in the presence of a hydrophobic neutral ligand and the extraction equilibrium of lanthanoids in the synergistic ionic-liquid extraction system were investigated. In the synergistic ionic-liquid extraction system of lanthanoids(III) (Ln(III)) using 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide as an ionic liquid, benzoylacetone (Hba) as an anionic chelating ligand, and trioctylphosphine oxide (TOPO) as a hydrophobic neutral ligand, the extraction selectivity of lanthanoids was remarkably enhanced by the selective synergism for heavier lanthanoids. It was found that the superior synergistic effect for heavier lanthanoids is observed when 
-diketones having a higher pK
value are used. The equilibrium analysis in the Hba-TOPO system indicated that both Ln(ba)(TOPO)
and Ln(ba)(TOPO)
were found as the extracted species.
Shimojo, Kojiro; Fujiwara, Iori*; Sugita, Tsuyoshi; Ueda, Yuki; Okamura, Hiroyuki; Oshima, Tatsuya*; Baba, Yoshinari*; Naganawa, Hirochika
no journal, ,
We have synthesized a thiodiglycolamic acid type ligand with a soft donor atom as a novel extractant. Extraction behavior of 56 metal ions using this extractant was comprehensively investigated. By comparing the extraction properties of this extractant with those of a diglycolamic acid type ligand with a hard donor atom, the effect of soft-hard property in the ether-site on extraction characteristics was clarified.
Sugita, Tsuyoshi; Okamura, Hiroyuki; Ueda, Yuki; Naganawa, Hirochika; Shimojo, Kojiro
no journal, ,
Ionic liquid extraction system has unique extraction property. In this study, novel organophosphate type neutral extractant with tridentate structure was synthesized and it's extraction ability and extraction mechanisms were revealed in ionic liquid system.
Ueda, Yuki; Sugita, Tsuyoshi; Okamura, Hiroyuki; Shimojo, Kojiro; Naganawa, Hirochika; Morisada, Shintaro*; Kawakita, Hidetaka*; Oto, Keisuke*
no journal, ,
Platinum group metals (PGMs) are indispensable metals in modern industries and are used for example as active components in automobile gas catalysts, jewelry goods, electronic devices and dental materials. In order to meet the growing demand, high efficient extraction reagents for liquid-liquid extraction of the respective anionic chloro-complexes are required in order to enhance capable winning from either pour geological deposits or complex secondary sources within the Urban Mining. The ligand containing urea or amide groups can form the hydrogen bond with anionic species. The novel urea or amide containing extraction reagents were synthesized and its extraction behavior and mechanism were investigated in this work.