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JAEA Reports

Investigation on the separation of Sr-90 from high-level liquid waste and the supply of Y-90 for medical application at a Reprocessing Research Facility

Saga, Kaname

JAEA-Review 2025-003, 23 Pages, 2025/05

JAEA-Review-2025-003.pdf:1.08MB

Diagnosis and treatment using radioisotopes (RI) in the medical field contribute to improving people's welfare. However, almost all medical RI distributed in Japan are imported from overseas. As a result, geopolitical influences and natural disasters lead to difficulties for importing them. Based on these backgrounds, in Japan, a specialized subcommittee on the production and utilization of medical radioisotopes was established within the Atomic Energy Commission, and in May 2022, it formulated the "Action Plan for Promotion of Production and Utilization of Medical Radioisotopes." Japan Atomic Energy Agency (JAEA) launched the NXR Development Center in FY2024 to separate and recycle valuable elements contained in high-level liquid waste (HLLW). The advantages of using HLLW are that it contains a wide variety of nuclides and in large quantities. Therefore, this report focused on the RI contained in HLLW and evaluated whether it can be supplied for medical use. Specifically, the target supply amount of Sr-90, the parent nuclide of Y-90 approved as a RI for medical use, and the amount of Sr-90 in HLLW were estimated. Based on the estimation, the feasibility of separating medical RI from HLLW in a reprocessing research facility was evaluated. As a result, the HLLW possibly contains an amount of RI equivalent to the domestic medical demand. Although it depends on the RI concentration in the HLLW, a small volume of HLLW, ranging from a few hundred milliliters to a few liters, could potentially produce an amount of medical RI equivalent to domestic demand. In addition, the equipment already installed in research facilities, such as NUCEF at JAEA, may be sufficient to produce the medical RI. It may be possible to meet domestic medical demand for Sr-90, as a source of Y-90, by processing a few hundred milliliters to a few liters of HLLW using an existing research facility.

Journal Articles

Extraction behaviors of minor actinides and rare earth elements with NTA amide extractants

Suzuki, Hideya*; Ban, Yasutoshi

Journal of Nuclear Science and Technology, 62(2), p.157 - 166, 2025/02

 Times Cited Count:0 Percentile:0.00(Nuclear Science & Technology)

Journal Articles

Solvent extraction of tin in nitric acids; Evaluation of multiple extractants

Ito, Kengo*; Takahashi, Shin*; Kato, Chizu*; Fukutani, Satoshi*; Matsumura, Tatsuro; Fujii, Toshiyuki*

Journal of Radioanalytical and Nuclear Chemistry, 334, p.2467 - 2475, 2025/02

 Times Cited Count:0 Percentile:0.00(Chemistry, Analytical)

In this study, the solvent extraction behavior of tin (Sn), specifically $$^{126}$$Sn, from high-level radioactive waste was evaluated using six different extractants in a HNO$$_{3}$$ system. Among the tested extractants, N,N-Didodecyl-2-hydroxyacetoamide (HAA) exhibited higher efficiency, still not sufficient for industrial implementation. In systems where HCl was added to HNO$$_{3}$$, both tributyl phosphate (TBP) and N,N,N,N'-tetra-2-ethylhexyl diglycolamide (TEHDGA) achieved D$$_{Sn}$$ values greater than 1 at $$>$$ 1 M HCl. However, due to practical challenges in industrial applications, HAA extraction in HNO$$_{3}$$ systems, particularly at low Sn concentrations (0.0008 M), may provide a more effective solution for Sn recovery.

Journal Articles

R&D on nuclear transmutation technology

Nishihara, Kenji

Enerugi, Shigen, 45(6), p.359 - 363, 2024/11

no abstracts in English

Journal Articles

New vortex tube for spot cooling

Kureta, Masatoshi

Kurin Tekunoroji, 34(11), p.70 - 76, 2024/11

no abstracts in English

Journal Articles

None

Nishihara, Kenji

Genshiryoku Nenkan 2025, p.75 - 80, 2024/10

no abstracts in English

Journal Articles

Solvent extraction of selenium in nitric acid; Evaluation of multiple extractants and proposal of a novel separation process

Ito, Kengo*; Kawakami, Takahiro*; Kato, Chizu*; Fukutani, Satoshi*; Matsumura, Tatsuro; Fujii, Toshiyuki*

Journal of Radioanalytical and Nuclear Chemistry, 333(10), p.5183 - 5189, 2024/10

 Times Cited Count:1 Percentile:57.00(Chemistry, Analytical)

Solvent extraction behaviors of Se (VI) from nitric acid solutions were investigated with multiple extractants used for uranium, plutonium, minor actinides, and rare earthelements separation processes from high-level liquid waste. During the processes, Se remained in the residual aqueous solutions, as all extractants showed distributionratios $$<$$ 1. In contrast, Se showed distribution ratios $$>$$ 1 with $$o$$-phenylenediamine in dilute nitric acid ($$<$$ 2 M HNO$$_{3}$$), octanol as the organic phase, and concentrated nitric acid (8 M HNO$$_{3}$$) for back extraction, suggesting a potential new single separation process and recovery of Se.

JAEA Reports

Investigation on partitioning and utilization of valuable elements and radio isotopes from spent nuclear fuel

Saga, Kaname

JAEA-Review 2024-038, 9 Pages, 2024/09

JAEA-Review-2024-038.pdf:0.88MB

The purpose of this report is understanding the elements and radio isotopes with highly useful based on the current trends in the industrial field. The survey was conducted from the viewpoint of the abundance of elements and radio isotopes contained and the demand in the industrial field, and the following survey results were obtained. The economic scale of radio isotopes in the industrial field (including radiation use) has been increasing in recent years in the manufacturing, medical, and agricultural sectors. On the other hand, the domestic production of the utilized radio isotope is still small, and some radio isotopes are entirely imported. Radio isotopes such as Sr-90, Mo-100, Cs-137, and Am-241 from spent fuel are suitable for industrial use because of their abundance in spent fuel and half-lives. As for the utilization of elements, the industrial use of platinum group elements and rare earth elements were explored because these elements are high industrial value and low domestic self-sufficiency. The platinum group elements were evaluated to have the potential to be supplied in a certain amount as a new domestic production source based on their abundance in spent fuel. On the other hand, for rare earth elements, which have also low self-sufficiency rate, the ratio of the amount that could be supplied from spent fuel compared to the current annual supply was evaluated to be less than 1%, and therefore, no effect could be expected. The domestic recycling rate of rare earth elements is low, and the provision of numerical simulation technology, which improves the recycling rate, could highly contribute to the industries. This technology makes it possible to calculate the optimal operating conditions for the separation process, such as the number of processing stages and processing speed, in accordance with the elements to be separated and used.

Journal Articles

Subangstrom tuning of pore size for selective separation of radioactive strontium over environmental calcium by lanthanide-oxalate frameworks

Nankawa, Takuya; Sekine, Yurina; Yamada, Teppei*

Nihon Genshiryoku Gakkai Wabun Rombunshi (Internet), 23(2), p.50 - 63, 2024/06

Selective separation of radioactive ions is essential for reducing or cleaning radioactive wastes. Among the radioisotopes to be removed, $$^{90}$$Sr poses a major threat to human health and the environment. However, removal of $$^{90}$$Sr from environmental wastewater is still challenging due to the difficulty of separating $$^{90}$$Sr$$^{2+}$$ from Ca$$^{2+}$$. Here, we developed a series of isostructural lanthanide oxalate frameworks (LOFs) comprising oxalate and eight kinds of lanthanide (Ln) ions, i.e., from Samarium (Sm) to Thulium (Tm) for application to selective removal of $$^{90}$$Sr from wastewater using its tuned porous structure. The LOFs had ion exchangeable anionic pores, in which the size of the pores changed in a stepwise manner depending on the host Ln species. When Tb was the host Ln of the LOF, the LOF showed extremely high Sr$$^{2+}$$ selectivity and was able to distinguish the subtle difference in ionic radius (0.2 ${AA}$) between Sr$$^{2+}$$ and Ca$$^{2+}$$. The Sr$$^{2+}$$ selectivity was higher than that of conventional adsorbents. The pore size tuning of the LOFs by selecting the constituent Ln species yielded a highly ion-selective adsorbent material. This novel strategy will be useful in developing custom porous materials that are easy to prepare and applicable across various fields.

Journal Articles

Flexible waste management system for the future application of MA P&T technology to the current high-level liquid waste

Fukasawa, Tetsuo*; Suzuki, Akihiro*; Endo, Yoichi*; Inagaki, Yaohiro*; Arima, Tatsumi*; Muroya, Yusa*; Endo, Keita*; Watanabe, Daisuke*; Matsumura, Tatsuro; Ishii, Katsunori; et al.

Journal of Nuclear Science and Technology, 61(3), p.307 - 317, 2024/03

 Times Cited Count:2 Percentile:46.61(Nuclear Science & Technology)

A flexible waste management system (FWM) is being developed to apply future MA partitioning and transmutation (P&T) technology to current HLLW. This FWM system will store high-level waste (HLLW) in granular form until MA partitioning and transmutation technology is realized. The feasibility of the main process was essentially confirmed by basic experiments and preliminary thermal analysis for granule production by rotary kiln from simulated HLLW and for temporary storage (50 years) of HLW granules at the HLW storage facility, respectively. The granule production experiments revealed that relatively large particles can be produced by the rotary kiln. The results of the thermal analysis showed that the small diameter canisters could be used to safely store the granules at a higher storage density than vitrified HLW. The effectiveness of the FWM system in terms of potential radiotoxicity and repository area was also evaluated, and it was shown that FWM can reduce these factors and has significant advantages in the disposal of HLW generated in current reprocessing plants. Since LWR fuel is stored for a long period of time in Japan and the operation of a reprocessing plant is expected to start soon, the FWM system is considered to be an effective system for reducing the environmental burden of HLW disposal.

Journal Articles

Depth concentration profile for cesium atom in fullerene C$$_{60}$$ investigated using synchrotron X-ray photoelectron spectroscopy

Sekiguchi, Tetsuhiro; Yokoyama, Keiichi; Yaita, Tsuyoshi

Photon Factory Activity Report 2023 (Internet), 5 Pages, 2024/00

For nuclear transmutation of cesium-135 ($$^{135}$$Cs), which is long-lived fission product, we are developing selective absorbent which takes only Cs atom in, but does not CsI. In this study, absorbing property of Cs atom or CsI into fullerene (C$$_{60}$$) solid has been investigated using synchrotron-based angle-dependent X-ray photoelectron spectroscopy (ARXPS). It was found that Cs penetrates into C$$_{60}$$ deep bulk. In contrast, CsI does not diffuse into bulk, although CsI over-layer was formed on the shallow surface. Furthermore, XPS spectra were measured as a function of Ar$$^{+}$$-sputtering time in order to know Cs concentration profiles in further deep region. Results showed that Cs penetrates into deep region of several hundreds ${AA}$.

Journal Articles

A Demonstration test to separate minor actinides in high-level liquid waste by ${it N,N,N',N',N'',N''}$-hexaoctyl nitrilotriacetamide (HONTA) using mixer-settler extractors in a hot cell

Ban, Yasutoshi; Suzuki, Hideya*; Hotoku, Shinobu; Tsubata, Yasuhiro

Solvent Extraction Research and Development, Japan, 31(1), p.1 - 11, 2024/00

A demonstration test was performed to separate minor actinides (MA; Am and Cm) by ${it N,N,N',N',N'',N''}$-hexaoctyl nitrilotriacetamide (HONTA) as an extractant using mixer-settler extractors installed in a hot cell. A high-level liquid waste containing MA, and rare earths (RE; Y, La, Nd, and Eu) was used as the feed. HONTA diluted to 0.05 mol/dm$$^{3}$$ in ${it n}$-dodecane was fed as the organic phase, and a part of the organic phase was reused without solvent regeneration. HONTA effectively extracted MA, whereas RE were less extractable. Consequently, the Y, La, Nd, and Eu ratios distributed to a RE fraction were $$>$$ 99.9%, 99.2%, 61.8%, and 81.4%, respectively. The Am and Cm ratios distributed to an MA fraction were 86.8% and 74.7%, respectively, and a substantial amount of MA (0.12 g) was recovered in the MA fraction by the end of the cumulative duration of 40 h.

Journal Articles

Study on $$^{rm 99m}$$Tc separation/concentration technology from $$^{99}$$Mo by (n, $$gamma$$) method

Fujita, Yoshitaka; Hu, X.*; Takeuchi, Tomoaki; Takeda, Ryoma; Fujihara, Yasuyuki*; Yoshinaga, Hisao*; Hori, Junichi*; Suzuki, Tatsuya*; Suematsu, Hisayuki*; Ide, Hiroshi

KURNS Progress Report 2022, P. 110, 2023/07

no abstracts in English

Journal Articles

Foam flotation of clay particles using a bifunctional amine surfactant

Micheau, C.; Ueda, Yuki; Motokawa, Ryuhei; Bauduin, P.*; Girard, L.*; Diat, O.*

Langmuir, 39(31), p.10965 - 10977, 2023/07

 Times Cited Count:11 Percentile:71.78(Chemistry, Multidisciplinary)

Journal Articles

Photochemical separation of elements in high level radioactive liquid waste

Matsuda, Shohei; Yokoyama, Keiichi

Isotope News, (786), p.6 - 9, 2023/04

no abstracts in English

Journal Articles

Toward nuclear transmutation

Maekawa, Fujio

Ryoshi Bimu Kagaku No Kiso To Oyo; NSA/Commentaries, No.27, p.15 - 25, 2023/03

The nuclear transmutation technology that is one of the most beneficial industrial applications of quantum beams to humankind is explained.

JAEA Reports

Present status of R&D in JAEA on partitioning and transmutation technology

Nuclear Science and Engineering Center; Fuel Cycle Design Office; Plutonium Fuel Development Center; Nuclear Plant Innovation Promotion Office; Fast Reactor Cycle System Research and Development Center; J-PARC Center

JAEA-Review 2022-052, 342 Pages, 2023/02

JAEA-Review-2022-052.pdf:18.05MB

This report summarizes the current status and future plans of research and development (R&D) on partitioning and transmutation technology in Japan Atomic Energy Agency, focusing on the results during the 3rd Medium- to Long-term Plan period (FY 2015-2021). Regarding the partitioning technology, R&D of the solvent extraction method and the extraction chromatography method are described, and regarding the minor actinide containing fuel technology, R&D of the oxide fuel production using the simplified pellet method, the nitride fuel production using the external gelation method, and pyrochemical reprocessing of the nitride fuel were summarized. Regarding transmutation technology, R&D of technology using fast reactors and accelerator drive systems were summarized. Finally, the new facilities necessary for the future R&D were mentioned.

Journal Articles

Lanthanide and actinide ion complexes containing organic ligands investigated by surface-enhanced infrared absorption spectroscopy

Hirata, Sakiko*; Kusaka, Ryoji; Meiji, Shogo*; Tamekuni, Seita*; Okudera, Kosuke*; Hamada, Shoken*; Sakamoto, Chihiro*; Honda, Takumi*; Matsushita, Kosuke*; Muramatsu, Satoru*; et al.

Inorganic Chemistry, 62(1), p.474 - 486, 2023/01

 Times Cited Count:3 Percentile:28.83(Chemistry, Inorganic & Nuclear)

Journal Articles

Study of non-destructive slow beam extraction method in particle accelerator

Nagayama, Shota; Harada, Hiroyuki; Shimogawa, Tetsushi*; Yamada, Ippei; Chimura, Motoki; Yamamoto, Kazami; Kinsho, Michikazu

Proceedings of 19th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.503 - 507, 2023/01

Synchrotron accelerators realize physics experiments and radiation cancer treatment using the slow extraction technique, in which beams are stored in the ring and gradually delivered. We have devised and are currently developing a "non-destructive electrostatic septum" based on a new method, which in principle cannot be solved by conventional methods and is a cause of equipment failure and output limitation. It is ideal to generate a force distribution similar to a staircase function with discontinuous gaps at the boundary. In this presentation, we will show the calculation method for optimizing the electrode and wire configuration to generate a Lorentz force with a distribution similar to a staircase function in vacuum, and the calculation results of the beam breakup due to the generated Lorentz force. The compact proof-of-principle machine developed for the ongoing demonstration of this method will also be introduced.

Journal Articles

Extraction properties of trivalent rare earth ions from nitric acid using a triamide-amine extractant

Uchino, Seiko*; Narita, Hirokazu*; Kita, Keisuke*; Suzuki, Hideya*; Matsumura, Tatsuro; Naganawa, Hirochika*; Sakaguchi, Koichi*; Oto, Keisuke*

Solvent Extraction Research and Development, Japan, 30(1), p.39 - 46, 2023/00

The extraction of trivalent rare earth ions (RE$$^{3+}$$) from HNO$$_{3}$$ solution using a triamide amine, tris(N,N-di-2-ethylhexyl-ethylamide)amine (DEHTAA), was conducted, and the extraction mechanism was estimated from extraction behavior of HNO$$_{3}$$ and RE$$^{3+}$$ and the relationship between atomic number and extraction percentages (E%) for RE$$^{3+}$$. A DEHTAA molecule dominantly formed a DEHTAA HNO$$_{3}$$ at 1.0 M HNO$$_{3}$$ and a DEHTAA(HNO$$_{3}$$)$$_{2}$$ at 6.0 M HNO$$_{3}$$ in the acid-equilibrated organic phase. This would provide the unique dependence of E% for the light RE$$^{3+}$$ on the HNO$$_{3}$$ concentration, in which the E% value had a minimum and maximum at $$sim$$0.5 M and $$sim$$2 M HNO$$_{3}$$, respectively. The results of the slope analyses for the distribution ratios for RE$$^{3+}$$ suggested that the dominant RE$$^{3+}$$ complex was RE(NO$$_{3}$$)$$_{3}$$DEHTAA(DEHTAA HNO$$_{3}$$) at 1.0 M HNO$$_{3}$$. The E% for RE$$^{3+}$$ decreased from La$$^{3+}$$ to Lu$$^{3+}$$ at 1.0 M HNO$$_{3}$$; on the other hand, those increased from La$$^{3+}$$ to Nd$$^{3+}$$ at 0.25 M and from La$$^{3+}$$ to Sm$$^{3+}$$ and 6.0 M HNO$$_{3}$$.

903 (Records 1-20 displayed on this page)