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JAEA Reports

Preparation of carbonate slurry simulating chemical composition of slurry in overflowed high integrity container and evaluation of its characteristics

Horita, Takuma; Yamagishi, Isao; Nagaishi, Ryuji; Kashiwaya, Ryunosuke*

JAEA-Technology 2021-012, 34 Pages, 2021/07

JAEA-Technology-2021-012.pdf:2.1MB
JAEA-Technology-2021-012(errata).pdf:0.15MB

Waste mainly consisting of carbonate precipitates (carbonate slurry) from the Advanced Liquid Processing System (ALPS) and the improved ALPS at the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Holdings, Inc. have been storing in the High Integrity Container (HIC). The supernatant solution of carbonate slurry contained in some of HICs were overflowed in April of 2015. The all of level of liquid in the HICs were investigated; however, almost of the HICs were under the level of overflow. The mechanism of overflow suggested to be depending on the difference of the properties of the carbonate slurry such as the retention/release characteristics of the bubbles. Therefore, in order to clarify the mechanism of leakage, the repeatability experiment was carried out by using simulated carbonate slurry. The simulated carbonate slurry was perpetrated by using the same cross-flow filter system of the actual ALPS. Moreover, the preparative conditions for the simulated carbonate slurry were the same as Mg/Ca concentration ratio in inlet water of the ALPS (raw water) and the ALPS operating conditions. The chemical characteristics of simulated carbonate slurries were revealed by ICP-AES, pH meter, etc. The density of the settled slurry layer tended to increase depending on the calcium concentration in the raw water. The bubble injection test was conducted in order to investigate the bubble retention/release behavior in the simulated carbonate slurry layer. The simulated carbonate slurry with high settling density, which was generated by high calcium concentration solution was revealed to retain the injected bubbles. Since the ratio of concentration calcium and magnesium during the carbonate slurry generation is assumed to affect the retention of bubbles in the slurry layer, the information on the composition of raw water is one of important factor for overflow of HICs.

Journal Articles

Experimental study on modeling of Pu sorption onto quartz

Hemmi, Ko; Walker, A.*; Yamaguchi, Tetsuji

Radiochimica Acta, 109(7), p.539 - 546, 2021/07

 Times Cited Count:0 Percentile:0.01(Chemistry, Inorganic & Nuclear)

Plutonium(IV) sorption onto quartz in carbonate solutions was systematically investigated under anaerobic conditions to analyze the sorption behaviors of Pu(IV) with a non-electrostatic model (NEM). Pu(IV) sorption data was obtained from batch sorption experiments as a function of pH and carbonate concentration. The Pu(IV) sorption onto quartz showed similar tendencies to Th(IV), which is considered to be chemically analogous as a tetravalent actinoid. The distribution coefficient, ${it K}$d, of Pu(IV) onto quartz showed inverse proportionality to the square of the total carbonate concentration under the investigated pH conditions of 8 to 11. The modeling study, however, revealed a Th(IV) sorption model, which is $$equiv$$SOTh(OH)$$_{4}$$$$^{-}$$ and $$equiv$$SOThOH(CO$$_{3}$$)$$_{2}$$$$^{2-}$$, could not be applied to simulate the Pu(IV) sorption onto quartz. It was inferred that the electrostatic repulsion between negatively charged ligands limited the formation of $$equiv$$SOM(OH)$$_{4}$$$$^{-}$$ and $$equiv$$SOMOH(CO$$_{3}$$)$$_{2}$$$$^{2-}$$ for Pu(IV) with smaller ionic radii than Th(IV). The Pu(IV) sorption model was developed as $$equiv$$SOPu(OH)$$_{3}$$ and $$equiv$$SOPu(OH)$$_{4}$$$$^{-}$$. In addition, data of Pu(IV) sorption onto muscovite was obtained in order to be compared with data for quartz.

Journal Articles

Incorporation of U, Pb and rare earth elements in calcite through crystallisation from amorphous calcium carbonate; Simple preparation of reference materials for microanalysis

Miyajima, Yusuke*; Saito, Ayaka*; Kagi, Hiroyuki*; Yokoyama, Tatsunori; Takahashi, Yoshio*; Hirata, Takafumi*

Geostandards and Geoanalytical Research, 45(1), p.189 - 205, 2021/03

 Times Cited Count:0 Percentile:0.01(Geochemistry & Geophysics)

Uncertainty for elemental and isotopic analyses of calcite by LA-ICP-MS is largely controlled by the homogeneity of the reference materials (RMs) used for normalization and validation. In order to produce calcite RMs with homogeneous elemental and isotopic compositions, we incorporated elements including U, Pb, and rare earth elements into calcite through heat- and pressure-induced crystallization from amorphous calcium carbonate that was precipitated from element-doped reagent solution. X-ray absorption spectra showed that U was present as U(VI) in the synthesized calcite, probably with a different local structure from that of aqueous uranyl ions. The uptake rate of U by our calcite was higher in comparison to synthetic calcite of previous studies. Variations of element mass fractions in the calcite were better than 12% 2RSD, mostly within 7%. The $$^{207}$$Pb/$$^{206}$$Pb ratio in the calcite showed $$<$$1% variations, while the $$^{238}$$U/$$^{206}$$Pb ratio showed 3-24% variations depending on element mass fractions. Using the synthetic calcite as primary RMs, we could date a natural calcite RM, WC-1, with analytical uncertainty as low as $$<$$3%. The method presented can be useful to produce calcite with controlled and homogeneous element mass fractions, and is a promising alternative to natural calcite RMs for U-Pb geochronology.

Journal Articles

A Thermodynamic model for the solubility of HfO$$_{2}$$(am) in the aqueous K$$^{+}$$ - HCO$$_{3}$$$$^{-}$$ - CO$$_{3}$$$$^{2-}$$ - OH$$^{-}$$ - H$$_{2}$$O system

Rai, D.*; Kitamura, Akira; Rosso, K.*

Radiochimica Acta, 105(8), p.637 - 647, 2017/08

 Times Cited Count:1 Percentile:15.39(Chemistry, Inorganic & Nuclear)

Solubility of HfO$$_{2}$$(am) was determined as a function of KHCO$$_{3}$$ concentrations ranging from 0.001 mol.kg$$^{-1}$$ to 0.1 mol.kg$$^{-1}$$. The solubility of HfO$$_{2}$$(am) increased dramatically with the increase in KHCO$$_{3}$$ concentrations, indicating that Hf(IV) makes strong complexes with carbonate. Thermodynamic equilibrium constants for the formation of Hf-carbonate complexes were determined using both the Pitzer and SIT models. The dramatic increase in Hf concentrations with the increase in KHCO$$_{3}$$ concentrations can best be described by the formation of Hf(OH-)$$_{2}$$(CO$$_{3}$$)$$_{2}$$$$^{2-}$$ and Hf(CO$$_{3}$$)$$_{5}$$$$^{6-}$$. The log$$_{10}$$ K$$^{0}$$ values for the reactions [Hf$$^{4+}$$ + 2 CO$$_{3}$$$$^{2-}$$ +2 OH$$^{-}$$ $$leftrightarrow $$ Hf(OH)$$_{2}$$(CO$$_{3}$$)$$_{2}$$$$^{2-}$$] and [Hf$$^{4+}$$ + 5 CO$$_{3}$$$$^{2-}$$ $$leftrightarrow $$ Hf(CO$$_{3}$$)$$_{5}$$$$^{6-}$$], based on the SIT model, were determined to be 44.53 $$pm$$ 0.46 and 41.53 $$pm$$ 0.46, respectively.

Journal Articles

Gas retention behavior of carbonate slurry under $$gamma$$-ray irradiation

Motooka, Takafumi; Nagaishi, Ryuji; Yamagishi, Isao

QST-M-2; QST Takasaki Annual Report 2015, P. 95, 2017/03

We conducted $$gamma$$ ray irradiation test using simulated carbonate slurry to investigate the cause of stagnant water over the high integrity container (HIC). This test was performed at Co-60 irradiation facility in Takasaki Advanced Radiation Research Institute. We observed a rise in water level, air bubbles in the slurry, a supernatant when the carbonate slurry with 95 g/L density was irradiated by $$gamma$$ ray at a dose rate of 8.5 kGy/h. The cause of the rise in water level was regarded as the volume expansion by the gas retention of the carbonate slurry. It was suggested that the cause of stagnant water over the high integrity container might be the volume expansion by the gas retention.

Journal Articles

The Role of low-temperature organic matter diagenesis in carbonate precipitation within a marine deposit

Miyakawa, Kazuya; Ishii, Eiichi; Hirota, Akinari*; Komatsu, Daisuke*; Ikeya, Kosuke*; Tsunogai, Urumu*

Applied Geochemistry, 76, p.218 - 231, 2017/01

 Times Cited Count:8 Percentile:49.44(Geochemistry & Geophysics)

no abstracts in English

Journal Articles

Sorption behavior of thorium onto granite and its constituent minerals

Iida, Yoshihisa; Yamaguchi, Tetsuji; Tanaka, Tadao; Hemmi, Ko

Journal of Nuclear Science and Technology, 53(10), p.1573 - 1584, 2016/10

 Times Cited Count:4 Percentile:45.9(Nuclear Science & Technology)

The sorption behavior of thorium (Th) onto granitic rock and its major constituent were investigated by batch sorption experiments. Experiments were carried out under variable pH and carbonate concentrations. Distribution coefficients decreased with increased carbonate concentrations and showed the minimal value at pH 9-10. This sorption tendency was likely due to forming the hydroxide-carbonate complexes of Th in the solutions. The order of sorbability for Th was mica $$>$$ feldspar $$>$$ quartz = granite. The sorption behaviors of Th onto these minerals were analyzed by the triple-layer surface complexation model with the Visual Minteq computer program. The model calculations assuming the inner-sphere surface complexation of Th were able to explain the experimental results reasonably well. It was shown that the sorption behavior of Th onto granite can be explained primarily by the complexation with the surface sites of feldspar.

Journal Articles

Diffusion and adsorption of uranyl ion in clays; Molecular dynamics study

Arima, Tatsumi*; Idemitsu, Kazuya*; Inagaki, Yaohiro*; Kawamura, Katsuyuki*; Tachi, Yukio; Yotsuji, Kenji

Progress in Nuclear Energy, 92, p.286 - 297, 2016/09

 Times Cited Count:6 Percentile:61.4(Nuclear Science & Technology)

Diffusion and adsorption behavior of uranyl (UO$$_2^{2+}$$) species is important for the performance assessment of radioactive waste disposal. The diffusion behaviors of UO$$_2^{2+}$$, K$$^{+}$$, CO$$_3^{2-}$$ and Cl$$^{-}$$ and H$$_{2}$$O in the aqueous solutions were evaluated by molecular dynamics (MD) calculations. The diffusion coefficient (De) of UO$$_2^{2+}$$ is the smallest and is 26% less than the self-diffusion coefficient of H$$_{2}$$O. For the aqueous solution with high concentration of carbonate ions, uranyl carbonate complexes: UO$$_{2}$$CO$$_{3}$$ and UO$$_{2}$$(CO$$_{3}$$)$$^{2-}$$ can be observed. For the clay (montmorillonite or illite)-aqueous solution systems, the adsorption and diffusion behaviors of UO$$_2^{2+}$$ and K$$^{+}$$ were evaluated by MD calculations. The distribution coefficients (Kd) increase with the layer charge of clay, and Kd of UO$$_2^{2+}$$ might be smaller than that of K$$^{+}$$. Further, their two-dimensional diffusion coefficients were relatively small in the adsorption layer and were extremely small for illite with higher layer charge.

Journal Articles

Influence of uranium enrichment on the etching rate of polycarbonate fission track detector containing uranium particles

Lee, C. G.; Iguchi, Kazunari; Esaka, Fumitaka; Magara, Masaaki; Sakurai, Satoshi; Watanabe, Kazuo; Usuda, Shigekazu

Nuclear Instruments and Methods in Physics Research B, 245(2), p.440 - 444, 2006/04

 Times Cited Count:7 Percentile:48.74(Instruments & Instrumentation)

The etching rates of fission track detectors made of polycarbonate containing uranium particles were measured after thermal neutron irradiation with fluence of 8$$times$$10$$^{14}$$ n/cm$$^{2}$$, in order to study the influence of uranium enrichment on the etching rate that was calculated from the weight loss by etching. There is a strong correlation between the etching rate of detector and the enrichment E of uranium particle: the former increases as the latter increases. Particularly, the etching rate per particle was proportional to E$$^{2/3}$$ rather than E$$^{1}$$, which is probably due to the overlapping of fission tracks. The etching behaviors of detector revealed that the existence of two different etching rate regions, a nonlinear region in the beginning of etching process and a subsequent constant region, which was explained as the opening of fission tracks and the broadening of opened tracks, respectively.

Journal Articles

Study on the etching conditions of polycarbonate detectors for particle analysis of safeguards environmental samples

Iguchi, Kazunari; Esaka, Konomi; Lee, C. G.; Inagawa, Jun; Esaka, Fumitaka; Onodera, Takashi; Fukuyama, Hiroyasu; Suzuki, Daisuke; Sakurai, Satoshi; Watanabe, Kazuo; et al.

Radiation Measurements, 40(2-6), p.363 - 366, 2005/11

 Times Cited Count:10 Percentile:59.05(Nuclear Science & Technology)

In particle analysis for safeguards environmental samples, the fission track technique is very important to detect sub-micrometer particles containing uranium. In the technique the authors developed, the particles were recovered onto the polycarbonate membrane filter. The filter was dissolved in solvent and dried to form a thin film of detector, in which the particles were confined. After thermal neutron irradiation and etching, the particles of interest in the detector were easily identified with fission tracks, and were picked up for isotope ratio analysis. It was found, however, that the particles in the vicinity of the detector surface may fall off during the etching process. Therefore, optimization of the etching condition is required. In this work, the effects of etching time and enrichment of uranium in particles were investigated. Preliminary results suggest that etching time should be shorter with the increase in the enrichment.

Journal Articles

Back-extraction of tri- and tetravalent actinides from diisodecylphosphoric acid (DIDPA) with hydrazine carbonate

Watanabe, Masayuki; Tatsugae, Ryozo*; Morita, Yasuji; Kubota, Masumitsu*

Journal of Radioanalytical and Nuclear Chemistry, 252(1), p.53 - 57, 2002/04

 Times Cited Count:5 Percentile:35.97(Chemistry, Analytical)

no abstracts in English

Journal Articles

Back-extraction of uranium(VI) from organophosphoric acid with hydrazine carbonate

Watanabe, Masayuki; Tatsugae, Ryozo*; Shirahashi, Koichi; Morita, Yasuji; Kubota, Masumitsu*

Journal of Radioanalytical and Nuclear Chemistry, 250(2), p.377 - 379, 2001/11

 Times Cited Count:5 Percentile:40.34(Chemistry, Analytical)

no abstracts in English

Journal Articles

Solvent-washing process using butylamine in fuel reprocessing

Uchiyama, Gunzo; Fujine, Sachio; Maeda, Mitsuru

Nuclear Technology, 120(1), p.41 - 47, 1997/10

 Times Cited Count:1 Percentile:15.04(Nuclear Science & Technology)

no abstracts in English

Journal Articles

Novel method for solving lithium carbonate pellet by binary-acid for tritium production rate measurement by liquid scintillation counting technique

Verzilov, Y.*; Maekawa, Fujio; Oyama, Yukio

Journal of Nuclear Science and Technology, 33(5), p.390 - 395, 1996/05

 Times Cited Count:16 Percentile:78.88(Nuclear Science & Technology)

no abstracts in English

Journal Articles

Solid-aqueous phase equilibria of uranium(VI) under ambient conditions

G.Meinrath*; ; Kimura, Takaumi; Yoshida, Zenko

Radiochimica Acta, 75(3), p.159 - 167, 1996/00

no abstracts in English

Journal Articles

Migration behavior of carbonate-$$^{14}$$C in tuffaceous soil

Nagao, Seiya;

Materials Research Society Symposium Proceedings, Vol.353, 0, p.1093 - 1100, 1995/00

no abstracts in English

Journal Articles

Electrolytic preparation of neptunium species in concentrated carbonate media

Y.Li*; ; Yoshida, Zenko

Radiochimica Acta, 60, p.115 - 119, 1993/00

no abstracts in English

Journal Articles

The Factors controlling vertical color variations of North Atlantic Madeira Abyssal Plain sediments

Nagao, Seiya;

Marine Geology, 109, p.83 - 94, 1992/00

 Times Cited Count:37 Percentile:73.29(Geosciences, Multidisciplinary)

no abstracts in English

Journal Articles

Thermal diffusivity measurement of molten alkali carbonate salts by use of a simple ceramic cell

; *; *; Katsuta, Hiroji

Thermal Conductivity,Vol.19, p.279 - 287, 1988/00

no abstracts in English

Journal Articles

Radiation-induced copolymerization of vinylene carbonate with methyl trifluoroacrylate

*; ; ; *;

Journal of Polymer Science; Polymer Chemistry Edition, 22, p.3417 - 3421, 1984/00

no abstracts in English

30 (Records 1-20 displayed on this page)