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Sakamoto, Tetsuo*; Morita, Masato*; Kanenari, Keita*; Tomita, Hideki*; Sonnenschein, V.*; Saito, Kosuke*; Ohashi, Masaya*; Kato, Kotaro*; Iguchi, Tetsuo*; Kawai, Toshihide*; et al.
Analytical Sciences, 34(11), p.1265 - 1270, 2018/11
Times Cited Count：8 Percentile：31.52(Chemistry, Analytical)Ban, Yasutoshi; Hagiya, Hiromichi; Sato, Makoto; Asakura, Toshihide; Morita, Yasuji
Proceedings of 3rd International ATALANTE Conference (ATALANTE 2008) (CD-ROM), 4 Pages, 2008/05
Since N,N-dialkylamide (monoamide) compounds extract tetravalent and hexavalent actinides, they have been proposed as alternative extractants to TBP. In the present work, numerical calculations for estimating separation performance of N,N-di(2-ethyl)hexyl-butanamide (D2EHBA) for U(VI) and Pu(IV) were carried out. A flow sheet was obtained which separate more than 99.9% of Pu(IV) from U(VI) by adjusting nitric acid concentration. Extraction properties of D2EHBA for macro concentrations of U (0.63-1.22 mol/dm
(M)) and Pu (6.3 mM) were studied in a batch manner. D2EHBA diluted to 1.5 M by n-dodecane extracted up to 0.8 M of U(VI) without forming precipitation and third phase. Distribution ratios of Pu(IV) were relatively high compared with the ones obtained at tracer concentrations of Pu(IV).
Imaizumi, Hirobumi; Ban, Yasutoshi; Sato, Makoto; Asakura, Toshihide; Morita, Yasuji
JAERI-Research 2005-025, 94 Pages, 2005/09
JAERI-Research-2005-025.pdf:13.61MB
Washing properties of n-butylamine compounds, which are decomposable by burning or electrolysis, for dibutylphosphoric acid (DBP) and Zr in real and simulated degraded solvents have been investigated. In experiments with simulated degraded solvents, basic properties of n-butylamine compounds for washing DBP and Zr were examined and optimum condition was obtained. It was confirmed from the simulated degraded solvent washing tests that 0.25 mol/dm n-butylamine oxalate of pH 2 could effectively remove Zr from the degraded solvent and the solution of pH 4 was effective for DBP, 95% removal of Zr and DBP were obtained by batch washing. The validity of n-butylamine as a degraded solvent wash reagent was shown by the washing test for real degraded solvent that was performed by continuous counter current flow using a miniature mixer-settler. The present study was carried out as a part of the joint study "Research and Development of Process Elements in an Advanced Aqueous Reprocessing" between Japan Nuclear Cycle Development Institute and JAERI.
Asakura, Toshihide; Sato, Makoto; Matsumura, Masakazu; Morita, Yasuji
JAERI-Conf 2005-007, p.345 - 347, 2005/08
This paper reviews the succeeding development and utilization of Extraction System Simulation Code for Advanced Reprocessing (ESSCAR). From the viewpoint of development, more tests with spent fuel and calculations should be performed with better understanding of the physico-chemical phenomena in a separation process. From the viewpoint of process safety research on fuel cycle facilities, it is important to know the process behavior of a key substance; being highly reactive but existing only trace amount.
*; Saido, Masahiro; Nakamura, Kazuyuki; Akiba, Masato; ; Goto, Yoshitaka*; *; *; Yamaki, Takahiro*; *; et al.
Journal of Nuclear Materials, 233-237(PT.A), p.781 - 786, 1996/00
Times Cited Count：13 Percentile：72.37(Materials Science, Multidisciplinary)no abstracts in English
Hotoku, Shinobu; Asakura, Toshihide; Sato, Makoto; Ban, Yasutoshi; Morita, Yasuji
no journal, ,
no abstracts in English
Noda, Kyoko*; Takao, Koichiro*; Sugiyama, Yuichi*; Harada, Masayuki*; Nogami, Masanobu*; Maruyama, Koichi*; Takahashi, Hiroaki*; Kim, S.-Y.; Sato, Makoto; Mineo, Hideaki; et al.
no journal, ,
We have been developing an advanced reprocessing system for spent FBR fuels based on precipitation method using pyrrolidone derivatives. In previous investigation, N-cyclohexyl-2-pyrrolidone (NCP) is used as a precipitant, which is able to precipitate selectively UO
ions in HNO
solution, and a process consisting of two separation steps; selective U precipitation step and U-Pu co-precipitation step, was developed. In order to make the process more effective and more economical, we are now studying precipitation of U and Pu with other pyrrolidone derivatives. The outline of the study and main results obtained until now are shown in this presentation.
Morita, Yasuji; Kim, S.-Y.; Kawata, Yoshihisa; Sato, Makoto; Ikeda, Yasuhisa*; Takao, Koichiro*; Noda, Kyoko*; Nishimura, Kenji*
no journal, ,
Precipitation behavior of Pu with pyrrolidone derivatives of N-(1,2-dimethyl)propyl-2-pyrrolidone (NDMProP) and N-neopenthyl-2-pyrrolidone (NNpP) in the solutions of U-Pu mixture has been examined in order to evaluate their applicability to the U-Pu co-precipitation process in the reprocessing based only on precipitation method. We have previously developed a process with N-cyclohexyl-2-pyrrolidone (NCP). It was found that U(VI) was precipitated in a high yield with any of the three precipitants and the precipitation yield of Pu(IV) was increased with the added amount of the precipitants. When NNpP was added with the ratio of [NNpP]/[U+Pu]=2.5, 99.5% of Pu was precipitate. Since NNpP showed the highest precipitation ability for Pu(IV) and the best physical property as precipitate, NNpP would be the most appropriate precipitant for the U-Pu co-precipitation process.
Kawata, Yoshihisa; Kim, S.-Y.; Sato, Makoto; Morita, Yasuji; Ikeda, Yasuhisa*; Kikuchi, Toshiaki*
no journal, ,
We have been developing an advanced reprocessing system for spent FBR fuels based on precipitation method using pyrrolidone derivatives. In the present study, the first precipitation step for selective U separation with N-n-butyl-2-pyrrolidone (NBP), concentration step and the second precipitation step for Pu and residual U separation with N-neopenthyl-2-pyrrolidone (NNpP) were tested using real fuel solution. U(VI) was precipitated as expected both in the first and second precipitation steps. In the concentration step, a part of Pu(IV) was oxidized to Pu(VI). The behavior pf Pu in the second precipitation step seemed to be influenced by the concentration step.
Tomita, Hideki*; Saito, Kosuke*; Ohashi, Masaya*; Sonnenschein, V.*; Kato, Kotaro*; Suzuki, So*; Iguchi, Tetsuo*; Morita, Masato*; Sakamoto, Tetsuo*; Kanenari, Keita*; et al.
no journal, ,
no abstracts in English
Iwata, Yoshihiro; Miyabe, Masabumi; Wakaida, Ikuo; Yoshimura, Shoki*; Matsumura, Tamaki*; Morita, Masato*; Sakamoto, Tetsuo*
no journal, ,
Information on the elemental and isotopic compositions of fuel debris is essential for the decommissioning of TEPCO's Fukushima Daiichi Nuclear Power Station. In this study, we have developed a double-resonance ionization scheme for highly sensitive and accurate isotope analysis of neodymium (Nd), which is a burnup indicator.
Yoshida, Takeru; Sekio, Yoshihiro; Maeda, Koji; Morita, Masato*; Sakamoto, Tetsuo*; Mizokami, Masato*; Hirai, Mutsumi*
no journal, ,
In order to steadily carry out decommissioning of the Fukushima Daiichi Nuclear Power Plant (FDNPP), it is extremely important to understand the properties of fuel debris. In the past, analytical methods such as SEM-EDS, TEM and ICP-MS have been used to determine the properties of fuel debris. However, these analytical methods cannot obtain information on the local isotopic composition of the sample. FIB-TOF-SIMS, which the authors are developing, is expected to be a useful analytical method for determining the properties of fuel debris because it allows local isotopic composition analysis. In this study, we conducted analysis in a micro-area of FDNPP contaminated sample and succeeded in obtaining isotopic composition imaging of Li, B, and U from the measured particulates.
Miyabe, Masabumi; Iwata, Yoshihiro; Tomita, Hideki*; Morita, Masato*; Sakamoto, Tetsuo*
no journal, ,
The isotopic composition of Nd is used in a wide range of nuclear field, such as forensic analysis and fuel burnup evaluation, and the currently most used analytical methods include TIMS and ICP-MS. However, the analytical samples obtained in decommissioning of Fukushima's failed reactors contain a mixture of particles of different sources, and these analytical techniques which cannot distinguish individual particles lose the information on their origin and history. Conversely, if the origin can be determined from the burnup of each particle, it is important for clarifying accident progress and criticality safety assessment. For this reason, we have applied ion sputter mass spectrometry imaging, which can measure the distribution of nuclides in individual particles, and have developed laser resonance secondary neutral mass spectrometry as a countermeasure against the isobaric interference. In this study, we performed two-step ionization spectroscopy to obtain highly efficient ionization schemes of Nd. As a result, we found several schemes with higher ionization efficiency than previously reported one.
