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Sakamoto, Atsushi; Kibe, Satoshi*; Kawanobe, Kazunori*; Fujisaku, Kazuhiko*; Sano, Yuichi; Takeuchi, Masayuki; Suzuki, Hideya*; Tsubata, Yasuhiro; Ban, Yasutoshi; Matsumura, Tatsuro
JAEA-Research 2021-003, 30 Pages, 2021/06
JAEA-Research-2021-003.pdf:1.81MB
Japan Atomic Energy Agency has been developing a solvent extraction process called SELECT to recover minor actinides (MA) from spent nuclear fuel. In the SELECT process, TDdDGA, HONTA, and ADAAM are used as the extractants for MA + Ln corecovery, MA/Ln separation and Am/Cm separation, respectively. These extractants do not contain phosphorus (P), and consist of carbon (C), hydrogen (H), oxygen (O), and nitrogen (N). In this study, in order to give beneficial information for designing flowsheet, the mass transfer coefficients of Ln between HNO
solution and TDdDGA or HONTA / n-dodecane solvent were evaluated by the single drop technique. Prior to the evaluation of mass transfer coefficient, we had optimized the structure of the single drop apparatus to improve accuracy of the measurement. Based on the mass transfer coefficients obtained in HNO / TDdDGA-n-dodecane system, Ln behaviors in the counter-current extraction and back-extraction using mixer-settlers and centrifugal contactors were estimated by simple calculation, and they had a good agreement with our previous experimental results. We also confirmed the mass transfer coefficients of Ln in HNO / HONTA - n-dodecane system are under 10
m/s.
Kibe, Satoshi; Fujisaku, Kazuhiko*; Sakamoto, Atsushi; Sano, Yuichi; Takeuchi, Masayuki; Suzuki, Hideya; Tsubata, Yasuhiro; Matsumura, Tatsuro
JAEA-Research 2016-024, 40 Pages, 2017/02
JAEA-Research-2016-024.pdf:6.73MB
The Japan Atomic Energy Agency has been developing some flowsheets with TDdDGA (N,N,N,Ntetradodecyldiglycolamide) extractant to recover MA (minor actinide) from raffinate. In this study, countercurrent experiments with the improved flowsheet, e.g. the addition of alcohol into the solvent for preventing the precipitation, were performed using miniature centrifugal contactors in order to compare the extraction/stripping behavior of each element with the mixer-settler type. As a result, no entrainments were observed and sufficient phase separation was achieved by centrifugal contactors without any abnormal fluid behavior, such as overflow. The extraction and stripping of Ln(III) which show the similar tendencies as MA could be achieved successfully, especially their stripping proceeded more efficiently in centrifugal contactors. This might be due to the increase in stripping rates by improving the flowsheet and to superior phase separation performance of centrifugal contactors.
Kibe, Satoshi; Fujisaku, Kazuhiko*; Ambai, Hiromu; Sakamoto, Atsushi; Sano, Yuichi; Takeuchi, Masayuki; Suzuki, Hideya; Tsubata, Yasuhiro; Matsumura, Tatsuro
JAEA-Research 2015-021, 40 Pages, 2016/02
JAEA-Research-2015-021.pdf:2.3MB
The flowsheet with TDdDGA extractant has been being developed for recovering MA from PUREX raffinate. In the previous study, the yields of MA and other elements in countercurrent extraction/stripping experiments using mixer-settlers were not enough for the target and it would be due to the insufficient phase (aqueous/organic) separation. In this study, we carried out countercurrent experiments with surrogate PUREX raffinate using centrifugal contactors which had superior phase separation ability, and evaluated the extraction/stripping behavior of each element. During the operation, abnormal fluid behavior, such as overflow and entrainment, was not observed, and sufficient phase separation was achieved by centrifugal contactors. Extraction behavior of lanthanides was similar to that in mixer-settlers, but their stripping efficiencies decreased. This would be due to shorter residence time in mixing zone.
Matsumura, Tatsuro; Suzuki, Hideya; Tsubata, Yasuhiro; Shibata, Mitsunobu; Kurosawa, Tatsuya; Kawasaki, Tomohiro; Sagawa, Hiroshi
no journal, ,
no abstracts in English
Kibe, Satoshi; Fujisaku, Kazuhiko*; Sakamoto, Atsushi; Sano, Yuichi; Takeuchi, Masayuki; Suzuki, Hideya; Tsubata, Yasuhiro; Matsumura, Tatsuro
no journal, ,
no abstracts in English
Sano, Yuichi; Sakamoto, Atsushi; Takeuchi, Masayuki; Suzuki, Hideya*; Matsumura, Tatsuro; Kawanobe, Kazunori*; Asano, Shusaku*; Maki, Taisuke*; Mae, Kazuhiro*
no journal, ,
The mass transfer coefficients during the extraction and back-extraction of lanthanide elements in the solvent extraction process using new extractants (TDdDGA, HONTA) developed for minor actinides (MA) recovery were evaluated. In the TDdDGA system, it was confirmed that the mass transfer coefficients during back extraction were improved by the addition of alcohol to the solvent, etc., and in the HONTA system, the mass transfer coefficients were relatively small.
Urabe, Shunichi; Tsubata, Yasuhiro; Suzuki, Hideya; Shibata, Mitsunobu; Kurosawa, Tatsuya; Kawasaki, Tomohiro; Matsumura, Tatsuro
no journal, ,
JAEA continues to carry out the development of the ADS (Double-strata). Mutual separation of MA and Ln is important for the development of the partitioning process. TDdDGA was performed using a mixer-settler equipment for the development of the separation process for MA. TDdDGA has a high extraction capacity. TDdDGA consists of C, H, O and N atoms (the CHON-principle). In this experiment, the feed solution as simulated HLLW contained fourteen elements. The results of the counter-current test showed that Am was extracted and was recovered in a high yield.
Matsumura, Tatsuro; Ban, Yasutoshi; Suzuki, Hideya; Tsubata, Yasuhiro; Hotoku, Shinobu; Tsutsui, Nao; Suzuki, Asuka
no journal, ,
The new reprocessing and minor actinide (MA) separation processes using innovative extractants in accord with CHON principle has been developed in Japan Atomic Energy Agency aimed for reduction of radioactive wastes from nuclear fuel cycle. The new nonorganophosphorus extractants which have appropriate extraction behaviors for each separation steps were developed. Continuous counter-current experiment of each solvent extraction process with uranium, plutonium and tracers of minor actinides were carried out. The experimental results showed that the separation performance of the solvent extraction processes were demonstrated successfully.
Sano, Yuichi; Kibe, Satoshi; Sakamoto, Atsushi; Takeuchi, Masayuki; Suzuki, Hideya; Tsubata, Yasuhiro; Matsumura, Tatsuro
no journal, ,
The flowsheet with TDdDGA extractant for recovering MA(III) from PUREX raffinate was evaluated by counter-current trials with surrogate PUREX raffinate using mixer-settlers and centrifugal contactors. The extraction and back-extraction of Ln(III) which show the similar tendencies as MA(III) could be achieved successfully, especially their back-extraction proceeded more efficiently in centrifugal contactors, which might be due to superior phase separation performance of centrifugal contactors.
Matsumura, Tatsuro; Ban, Yasutoshi; Suzuki, Hideya; Tsubata, Yasuhiro; Hotoku, Shinobu; Tsutsui, Nao; Suzuki, Asuka; Toigawa, Tomohiro; Kurosawa, Tatsuya*; Shibata, Mitsunobu*; et al.
no journal, ,
PUREX process was established for industrial scale reprocessing plant. TRUEX and the 4 group separation were developed for partitioning of minor actinides from HLW, and demonstrated using genuine HLW. Although the extractants for the processes have excellent performance, the molecules contain phosphorus which could be cause for the secondary waste from the solvent extraction processes. To minimize the radioactive waste, we have conducted research and development of the new reprocessing and MA separation processes using innovative extractants in accord with CHON principle. The extractants for reprocessing process are monoamides as alternative extractants for TBP. For An(III)+RE recovery process, we developed TDdDGA. HONTA and ADAAM were developed for An(III)/RE separation process and Am/Cm separation process respectively. The separation performances of the flowsheets were evaluated by continuous extraction tests using simulated and genuine spent fuel and high level liquid waste.
Matsumura, Tatsuro; Ban, Yasutoshi; Suzuki, Hideya; Tsubata, Yasuhiro; Toigawa, Tomohiro; Tsutsui, Nao; Hotoku, Shinobu; Suzuki, Asuka
no journal, ,
no abstracts in English
Matsumura, Tatsuro; Ban, Yasutoshi; Suzuki, Hideya; Tsubata, Yasuhiro; Hotoku, Shinobu; Tsutsui, Nao; Suzuki, Asuka; Toigawa, Tomohiro; Kurosawa, Tatsuya*; Shibata, Mitsunobu*; et al.
no journal, ,
To continue the utilization of the nuclear fission energy, the management of the high-level radioactive waste is one of the most important issues to be solved. Partitioning and Transmutation technology is expected to be effective to mitigate the burden of the HLW disposal by reducing the radiological toxicity and heat generation. JAEA has been conducting R&D on the MA separation process to remove of MA from HLW and supply the recovered MA to the transmutation system such as ADS. The MA separation process contains three steps. For An(III)+RE recovery process, we developed TDdDGA which has very high performance to recover of MA from high level waste. HONTA and ADAAM were developed for An(III)/RE separation process and Am/Cm separation process respectively. All extractants satisfy CHON principle to minimization of the secondary waste from the process. The separation performances of the flowsheets were evaluated by continuous extraction tests using simulated and genuine high level liquid waste.
Matsumura, Tatsuro; Suzuki, Hideya; Tsubata, Yasuhiro; Shibata, Mitsunobu; Kurosawa, Tatsuya; Kawasaki, Tomohiro; Sagawa, Hiroshi
no journal, ,
no abstracts in English
Sano, Yuichi; Kawanobe, Kazunori*; Sakamoto, Atsushi; Kofuji, Hirohide; Takeuchi, Masayuki; Suzuki, Hideya; Matsumura, Tatsuro
no journal, ,
Japan Atomic Energy Agency (JAEA) has developed several new extractants which are significantly effective in trivalent minor actinides (MA(III)) recovery from high acidic media such as high level liquid waste (HLLW). In order to design an efficient MA(III) recovery process using these new extractants, it is important to obtain their kinetic data as well as equilibrium ones in the solvent extraction system. In this study, mass transfer coefficients of trivalent lanthanides (Ln(III)), which are surrogates of MA(III), between HNO solution and tetra dodecyl diglycol amide (TDdDGA) or hexa octyl nitrilo triacetic amide (HONTA) / n-dodecane solvent were evaluated by the single drop technique and Nitsch cell tests. The mass transfer coefficients of Ln(III) back-extraction in HNO / TDdDGA system were relatively smaller than those in the extraction step, but they could be improved by the addition of 2-ethyl-1-hexanol into the TDdDGA / n-dodecane solvent. The mass transfer of Ln(III) between HNO solution and HONTA/n-dodecane solvent was considerably slower than that between HNO solution and TDdDGA / n-dodecane solvent. Based on the mass transfer coefficients obtained in these evaluations, process conditions for MA(III) recovery using mixer-settlers and centrifugal contactors were discussed.
Matsumura, Tatsuro; Ban, Yasutoshi; Suzuki, Hideya; Tsubata, Yasuhiro; Hotoku, Shinobu; Tsutsui, Nao; Toigawa, Tomohiro
no journal, ,
To minimize the radioactive waste from nuclear fuel cycle, we have conducted research and development of the new reprocessing and MA separation process, SELECT process (Solvent Extraction from Liquid-waste using Extractants of CHON-type for Transmutation), using innovative extractants. The extractants for each solvent extraction processes were developed in JAEA. The extractants for reprocessing process are monoamides as alternative extractants for TBP. For MA+RE recovery process, we developed TDdDGA which has very high performance to recover of MA from high level waste. HONTA and ADAAM were developed for MA/RE separation process and Am/Cm separation process respectively. All of the extractants consist of C, H, O, and N elements, and can be decomposed to gases by incineration. The demonstration tests using genuine spent fuel and high level liquid waste of the SELECT process have been conducted. Uranium solution and U+Pu mixed solution were separated from spent fuel, and MA, americium and curium, were recovered and separated from HLW effectively. The details of the extraction tests for each separation processes will be presented in correspond presentations in this conference.
Matsumura, Tatsuro; Ban, Yasutoshi; Hotoku, Shinobu; Suzuki, Hideya; Tsubata, Yasuhiro; Tsutsui, Nao; Suzuki, Asuka
no journal, ,