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Asai, Shiho; Hanzawa, Yukiko; Konda, Miki; Suzuki, Daisuke; Magara, Masaaki; Kimura, Takaumi; Ishihara, Ryo*; Saito, Kyoichi*; Yamada, Shinsuke*; Hirota, Hideyuki*
Talanta, 185, p.98 - 105, 2018/08
Times Cited Count:8 Percentile:31.52(Chemistry, Analytical)Estimating the risks associated with radiation from long-lived fission products (LLFP) in radioactive waste is essential to ensure the long-term safety of potential disposal sites. In this study, the amount of Zr, a LLFP, was determined by ICP-MS after separating Zr from a spent nuclear fuel solution using a microvolume anion-exchange cartridge (TEDA cartridge). The TEDA cartridge achieved highly selective separation of Zr regardless of its small bed volume of 0.08 cm. The time taken to complete the Zr separation was 1.2 min with a flow rate of 1.5 mL/min, which was 10 times faster than that for a conventional anion-exchange resin column. Almost all the other elements were removed, leading to accurate measurement of Zr. The result connects experimental value to theoretical prediction provided by ORIGEN2, which requires verification. With the measured value, we demonstrated that the theoretical value is reliable enough to estimate radiation risks.
Konda, Miki; Asai, Shiho; Hanzawa, Yukiko; Magara, Masaaki
JAEA-Technology 2015-054, 22 Pages, 2016/03
Isotope dilution mass spectrometry (IDMS) with ICP-MS is reliable method for determination of Zr-93, which is one of the long-lived fission products found in spent nuclear fuel and high-level radioactive wastes. In order to use an isotope standard solution of zirconium as the spike for IDMS, dissolving a commercially available solid isotope standard is indispensable. Prior to the dissolution of the Zr-91 isotope standard, solubility of metal zirconium in a mixture of HNO and HF was evaluated using zirconium metal chips. Then, 2 mg of the Zr-91 isotope standard was dissolved with 0.2 mL of 1 M HNO-3 v/v% HF mixed solution, followed by adjusting the concentration of Zr-91 to approximately 1,000 g/g. IDMS, in which a natural isotopic abundance standard solution of zirconium was used as the spike, was employed for the determination of the concentration of Zr-91 in the prepared Zr-91 isotope standard solution. The concentration of Zr-91 in the prepared Zr-91 isotope standard solution was (9.61.0) 10 g/g, which is in good agreement with the predicted concentration. This indicates that the Zr-91 metal isotope standard was completely dissolved with sufficient chemical stability. Additionally, no impurities were detected in the prepared Zr-91 isotope standard solution. These positive results denote that the Zr-91 isotope standard solution with the preferable quality for IDMS of Zr-93 can be obtained by the proposed dissolution procedures.
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Bunseki Kagaku, 36(7), p.T77 - T80, 1987/07
no abstracts in English
Bunseki Kagaku, 30, p.T103 - T105, 1981/00
no abstracts in English
Konda, Miki; Asai, Shiho; Hanzawa, Yukiko; Magara, Masaaki
no journal, ,
It is important to measure the inventory of radionuclides in high-level radioactive waste for safe and reasonable geological disposal of the waste. For verification of the reliability of the inventory assessment by measured value, we planned to quantify the long-lived nuclides Zr, that is important for safety evaluation of radioactive waste disposal, using isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) we developed. Spike (isotope standard solution) is required to apply the IDMS. We prepare Zr isotope standard solution by dissolving the metallic Zr isotope standard. The metallic Zr dissolves in HF, but HF dissolve glass and has high toxicity. Therefore it is necessary to reduce an amount of HF and to simplify a dissolution method. At first, we examined the dissolution method of the metallic Zr. The isotope standard of Zr was dissolved under optimum condition that obtained by the previous examination. The prepared Zr isotope standard solution was measured using the IDMS to determine concentration, which gave us a high-accuracy value.
Asai, Shiho; Hanzawa, Yukiko; Konda, Miki; Suzuki, Daisuke; Magara, Masaaki; Kimura, Takaumi; Ishihara, Ryo*; Saito, Kyoichi*; Yamada, Shinsuke*; Hirota, Hideyuki*
no journal, ,
Zr is a long-lived fission product which can be found in spent nuclear fuel and HLW. The estimation of theZr content is indispensable to achieve a safety disposal of HLW because Zr is predicted to be one of the major contributors to radiation dose. However, only a few measured Zr values have been reported, leading to a high demand for development of an efficient analytical method. Our group has been prepared a new porous filter cartridge which has densely bound ion-exchanger onto the pore surface of the filter, enabling a high-capacity and rapid adsorption. In order to apply this filter cartridge to a pretreatment for the Zr measurement with ICP-MS, an elution profiles of Zr and the other coexisting elements were examined. According to the resultant separation conditions, Zr in a spent nuclear fuel sample was successfully separated. The measured Zr content is 98.2 5.1 ng, which agrees with the theoretical value.
Asai, Shiho; Hanzawa, Yukiko; Konda, Miki; Suzuki, Daisuke; Magara, Masaaki; Kimura, Takaumi
no journal, ,
Various Zr isotopes generated by U fission are found in spent fuel and HLW. Among them, Zr which has a long half-life of 1.510y has a potential to contribute to radiation dose over an extended period of time after the implementation of HLW disposal. The inventory estimation of Zr in HLW confirmed by measured data is the key to realize a safe and cost-efficient disposal. In this study, a simple and robust analytical technique for the determination of Zr based on ion-exchange chromatography combined with ICP-MS was developed. Interference-free measurement was achieved by a single anion-exchange step, removing Sr, Nb, and Mo which would cause spectral interferences. Additionally, major component U and radioactive components, such as Cs, Ba, and Pu, were also removed concurrently. Concentration of Zr was readily calculated with measured isotope ratios of Zr/Zr in the sample and natural Zr-spiked sample with sufficient accuracy.
Horigome, Kazushi; Suzuki, Yoshimasa; Yamamoto, Masahiko; Taguchi, Shigeo; Kuno, Takehiko; Surugaya, Naoki
no journal, ,
no abstracts in English
Asai, Shiho; Hanzawa, Yukiko; Konda, Miki; Suzuki, Daisuke; Magara, Masaaki; Kimura, Takaumi
no journal, ,
Isotopes of Zr and Mo including both radio and stable isotopes can be found in spent nuclear fuel. Of these isotopes, Zr and Mo which have long half-lives of 1.61 10 y and 4 10 y, respectively, are of great importance from the viewpoint of managing high-level radioactive wastes in a long-term basis. In this study, contents of Zr and Mo isotopes in spent nuclear fuel solution were determined by isotope dilution inductively coupled plasma mass spectrometry. The sample solution was prepared by dissolving a Japanese PWR irradiated UO fuel with a burnup of 51 GWd/t. The measured contents of Zr, Zr, Zr, Zr, Zr, and Zr in the sample were agreed well with the predicted values obtained through a burnup calculation code ORIGEN2. For Mo, the contents in the sample were approximately 30% less than the predicted values, indicating that part of Mo exists in the insoluble residue.
Shibano, Koya; Okazaki, Hiro; Sumi, Mika; Kayano, Masashi; Matsuyama, Kazutomi; Kageyama, Tomio; Fujiwara, Hideki*; Furuta, Koya*; Yamaguchi, Kazuya*; Saito, Shingo*
no journal, ,
no abstracts in English
Ono, Shimpei; Kawanobe, Takayuki*; Watahiki, Hiromi; Shibata, Atsuhiro; Nomura, Kazunori
no journal, ,
no abstracts in English
Sato, Hinata; Horigome, Kazushi; Yamamoto, Masahiko; Taguchi, Shigeo
no journal, ,
Isotope dilution mass spectrometry (IDMS), which can measure U and Pu with high accuracy, is applied to determine U and Pu for the nuclear material accountancy in Tokai Reprocessing Plant. In the past, authors prepared a liquid spike containing mg amounts of Pu and U in a vial as a spike for U and Pu in dissolved solutions of U and Pu mixed oxide powder. In this study, the influence of long-term storage of liquid spike on the analytical results has been evaluated.
Sato, Hinata; Horigome, Kazushi; Yamamoto, Masahiko; Taguchi, Shigeo
no journal, ,
no abstracts in English