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Mishima, Ria; Inaba, Yusuke*; Tachioka, Sotaro*; Harigai, Miki*; Watanabe, Shinta*; Onoe, Jun*; Nakase, Masahiko*; Matsumura, Tatsuro; Takeshita, Kenji*
Chemistry Letters, 49(1), p.83 - 86, 2020/01
Times Cited Count:4 Percentile:20.61(Chemistry, Multidisciplinary)Separation of platinum group metals (PGMs) from high-level liquid waste generated from the reprocessing of spent nuclear fuels is important to produce good quality vitrified glass for final disposal. A new sorbent, Aluminum hexacyanoferrate (AlHCF), was synthesized and the general sorption behavior of PGMs from concentrated nitric acid was examined. Nitric acid caused substantial elution of AlHCF but the sorption of Pd stabilized the structure. Consequently, Rh was sorbed in the presence of Pd, whereas single Rh sorption caused complete dissolution of AlHCF. Relation between sorbed mount of Pd vs eluted Al and Fe revealed that the elution ratio of Al and Fe was not the same as molar ratio of synthesized AlHCF, indicating the re-sorption of Fe resulted in formation of new structure. The sorption mechanism of PGMs by this new sorbent, AlHCF, not only the simple ion exchange, but also oxidation reduction reaction as well as kinetics play important rule. Understanding the general sorption and dissolution behavior will help improve the sorption performance of PGMs by AlHCF.
Kurihara, Masayoshi*; Onoe, Jun*; Hirata, Masaru; Suzuki, Chikashi
Journal of Alloys and Compounds, 509(4), p.1152 - 1156, 2011/01
Times Cited Count:3 Percentile:24.03(Chemistry, Physical)The alloying behavior of transition metals (TMs) in solid -phase uranium (-U), which is expected to be used as fuel for next-generation nuclear reactors, is investigated using the discrete-variational Dirac-Fock-Slater molecular orbital method. Using a model cluster, U/TM, as the minimum unit of -U/TM alloys, we evaluate the d-orbital energy of the TM (Md), the bond order between the TM and U atoms, and the orbital overlap population (OOP) between the atomic orbitals of the TM and U atoms. We subsequently examine the effect of these quantities on the maximum solid solubility (MSS) of the -U/TM alloys. Md and the OOP (U 6d-TM d) exhibit good correlations with the MSS for -U/TM alloys, so that the interaction between the U-6d and TM-d atomic orbitals is found to play a key role in determining the MSS of the -U/TM alloys. The magnitude of the MSS can be explained in terms of the stabilization energy caused by U 6d-TM d orbital interactions for -U/TM alloys, which is affected by the Md and the OOP. The exponential dependence of the MSS on Md and the OOP is explained in terms of the equilibrium constant obtained using a substitution cluster model for -U/TM alloys. We also map the MSS of -U/TM alloys using the Md and the OOP as the alloying parameters. These results will assist the quantum design of nuclear fuel materials for other alloy systems besides the present alloy system.
Kurihara, Masayoshi*; Hirata, Masaru; Onoe, Jun*; Nakamatsu, Hirohide*
Progress in Nuclear Energy, 50(2-6), p.549 - 555, 2008/03
Times Cited Count:1 Percentile:10.01(Nuclear Science & Technology)The alloying behavior of 4d and 5d transition metals (TMs) in -phase solid uranium (U) has been investigated using the discrete-variational Dirac-Fock-Slater (DV-DFS) method. We examined the d-orbital energy (Md value) of these TMs, the orbital overlap population (OOP) between the d-orbital of these TMs and the 5f or 6d orbital of -U, and the effective charge on each atom of the -U/TM alloy, and the effect of these parameters on alloying. It was found that the maximum solid solubility of TMs into -U was exponentially proportional to both the Md and the OOP (U5f-TMd and U6d-TMd). We found a good correlation between the MSS and Md, the effective charge, or OOP.
Kurihara, Masayoshi*; Hirata, Masaru; Sekine, Rika*; Onoe, Jun*; Nakamatsu, Hirohide*
Journal of Nuclear Materials, 326(2-3), p.75 - 79, 2004/03
Times Cited Count:12 Percentile:61.44(Materials Science, Multidisciplinary)We have investigated the alloying behavior of g-uranium with 3d transition metals (TMs) using the relativistic discrete-variational Dirac-Fock-Slater (DV-DFS) method. The d-orbital energy (Md) as an alloying parameter well reproduces the alloying behavior of g- uranium metal with TMs: (1) in the case of a large Md value (Ti,V,Cr), the solubility of these TM elements in g-uranium becomes large; (2) in the case of a middle Md value (Mn,Fe,Co), the tendency to form a uranium intermetallic compound with these elements becomes stronger; (3) in the case of a small Md value (Cu), the alloying element is insoluble in g-uranium. The alloying behavior of g-uranium with TMs is also discussed in terms of other parameters such as electronegativity and metallic radius.
Hirata, Masaru; Bastug, T.*; Tachimori, Shoichi; Sekine, Rika*; Onoe, Jun*; Nakamatsu, Hirohide*
Advances in Quantum Chemistry, Volume 37, p.325 - 333, 2001/00
no abstracts in English
Hirata, Masaru; Tachimori, Shoichi; Sekine, Rika*; Onoe, Jun*; Nakamatsu, Hirohide*
Advances in Quantum Chemistry, Volume 37, p.335 - 351, 2001/00
no abstracts in English
Kurihara, Masayoshi*; Hirata, Masaru; Sekine, Rika*; Onoe, Jun*; Nakamatsu, Hirohide*
Journal of Nuclear Materials, 281(2-3), p.140 - 145, 2000/10
Times Cited Count:3 Percentile:26.4(Materials Science, Multidisciplinary)no abstracts in English
Hirata, Masaru; Bastug, T.*; Sekine, Rika*; Onoe, Jun*; Nakamatsu, Hirohide*; Mukoyama, Takeshi*
JAERI-Review 99-008, 29 Pages, 1999/03
no abstracts in English
Kurihara, Masayoshi*; Hirata, Masaru; Sekine, Rika*; Onoe, Jun*; Nakamatsu, Hirohide*; Mukoyama, Takeshi*; *
Journal of Alloys and Compounds, 283, p.128 - 132, 1999/00
Times Cited Count:10 Percentile:59.54(Chemistry, Physical)no abstracts in English
Hirata, Masaru; Sekine, Rika*; Onoe, Jun*; Nakamatsu, Hirohide*; Mukoyama, Takeshi*; *; Tachimori, Shoichi
Journal of Alloys and Compounds, 271-273, p.128 - 132, 1998/00
Times Cited Count:8 Percentile:52.58(Chemistry, Physical)no abstracts in English
Hirata, Masaru; *; Sekine, Rika*; Onoe, Jun*; Nakamatsu, Hirohide*; Mukoyama, Takeshi*; *; *
Journal of Electron Spectroscopy and Related Phenomena, 83(1), p.59 - 64, 1997/00
Times Cited Count:19 Percentile:63.14(Spectroscopy)no abstracts in English
Onoe, Jun*; Kurihara, Masayoshi*; Hirata, Masaru; Suzuki, Chikashi
no journal, ,
Amamoto, Ippei; Kobayashi, Hidekazu; Ayame, Yasuo; Utsumi, Kazuo*; Takeshita, Kenji*; Onoe, Jun*; Nagayama, Sachiko*; Hasegawa, Yoshio*
no journal, ,
no abstracts in English
Amamoto, Ippei; Kobayashi, Hidekazu; Ayame, Yasuo; Utsumi, Kazuo*; Takeshita, Kenji*; Onoe, Jun*; Nagayama, Sachiko*; Hasegawa, Yoshio*
no journal, ,
no abstracts in English
Kobayashi, Hidekazu; Ayame, Yasuo; Ishidera, Takamitsu; Utsumi, Kazuo*; Takeshita, Kenji*; Onoe, Jun*; Nagayama, Sachiko*; Hasegawa, Yoshio*; Amamoto, Ippei
no journal, ,
no abstracts in English
Amamoto, Ippei; Kobayashi, Hidekazu; Ayame, Yasuo; Hasegawa, Yoshio*; Utsumi, Kazuo*; Takeshita, Kenji*; Inaba, Yusuke*; Onoe, Jun*; Koshizaka, Akiko*; Kaneta, Yui*
no journal, ,
no abstracts in English
Amamoto, Ippei; Kobayashi, Hidekazu; Ayame, Yasuo; Onishi, Takashi; Inaba, Yusuke*; Utsumi, Kazuo*; Takeshita, Kenji*; Onoe, Jun*; Koshizaka, Akiko*; Hasegawa, Yoshio*
no journal, ,
The development on synthesis of sorbent was carried out to separate the platinum group species such as Ru, Rh and Pd in high-level radioactive liquid waste. After sorption test using developed sorbents, the spherical porous silica impregnated aluminium ferrocyanide was effective to sorb the species of Ru and Pd in the nitric solution. This sorption effect remained stable when tested on actual high-level radioactive liquid waste. It was found that more treated waste could be loaded into the borosilicate glass than untreated waste.
Mishima, Ria; Tachioka, Sotaro*; Inaba, Yusuke*; Harigai, Miki*; Matsumura, Tatsuro; Watanabe, Shinta*; Onoe, Jun*; Nakase, Masahiko*; Takeshita, Kenji*
no journal, ,
In Japan, the final disposal of high level liquid waste (HLLW) will be done after vitrification into borosilicate glass and then disposed into deep underground. In this vitrification process, there are some concerns. The first concern is precipitation of platinum group metals (PGMs) in the melter due to their low solubility into borosilicate glass. The second concern is the formation of yellow phase caused by Mo content. The final concern is the generation of huge number of vitrified glasses and the requirement of wide space needed for final disposal. Among many kinds of extractants and adsorbents for separation of such metal ions, metal hexacyanoferrate (HCFs) were reported to have an ability to adsorb PGMs. The objective of this study is to elucidate the adsorption behavior of aluminum hexacyanoferrate (AlHCF) for various metal ions and understand the relation between elution and adsorption. The effect of synthetic and workup conditions on PGM and Mo adsorption from simulated HLLW (sHLLW) was surveyed. Also, the relationship between adsorption of metal ions and elution of the AlHCF was studied. The synthesized AlHCF showed adsorption performance for PGMs and Mo in simulated HLLW. As a result of an adsorption test with a Pd single component solution to investigate the adsorption mechanism, the eluted element ratio was Fe:Al = 1:4 in the Pd adsorption test. However, the element ratio was Fe:Al = 3:4 in the original AlHCF. Therefore, it was suggested the existence of not only Pd adsorption, but also resorption and stabilization mechanisms.
Mishima, Ria; Tachioka, Sotaro*; Inaba, Yusuke*; Harigai, Miki*; Matsumura, Tatsuro; Watanabe, Shinta*; Onoe, Jun*; Nakase, Masahiko*; Takeshita, Kenji*
no journal, ,
In Japan, the final disposal of high level liquid waste (HLLW) will be done after vitrification into borosilicate glass and then disposed into deep underground. In this vitrification process, there are some concerns. The first concern is precipitation of platinum group metals (PGMs) in the melter due to their low solubility into borosilicate glass. The second concern is the formation of yellow phase caused by Mo content. The final concern is the generation of huge number of vitrified glasses and the requirement of wide space needed for final disposal. Among many kinds of extractants and adsorbents for separation of such metal ions, metal hexacyanoferrate (HCFs) were reported to have an ability to adsorb PGMs. The objective of this study is to elucidate the adsorption behavior of aluminum hexacyanoferrate (AlHCF) for various metal ions and understand the relation between elution and adsorption. The effect of synthetic and workup conditions on PGM and Mo adsorption from simulated HLLW (sHLLW) was surveyed. Also, the relationship between adsorption of metal ions and elution of the AlHCF was studied. The synthesized AlHCF showed adsorption performance for PGMs and Mo in simulated HLLW. As a result of an adsorption test with a Pd single component solution to investigate the adsorption mechanism, the eluted element ratio was Fe:Al = 1:4 in the Pd adsorption test. However, the element ratio was Fe:Al = 3:4 in the original AlHCF. Therefore, it was suggested the existence of not only Pd adsorption, but also resorption and stabilization mechanisms.