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Separation study of silver radionuclides from a palladium target irradiated by cyclotron
https://repo.qst.go.jp/records/76120
https://repo.qst.go.jp/records/76120eac0a78f-b0c2-4667-8576-245d91863f75
Item type | 会議発表用資料 / Presentation(1) | |||||
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公開日 | 2019-06-03 | |||||
タイトル | ||||||
タイトル | Separation study of silver radionuclides from a palladium target irradiated by cyclotron | |||||
言語 | ||||||
言語 | eng | |||||
資源タイプ | ||||||
資源タイプ識別子 | http://purl.org/coar/resource_type/c_c94f | |||||
資源タイプ | conference object | |||||
アクセス権 | ||||||
アクセス権 | metadata only access | |||||
アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
著者 |
Ohya, Tomoyuki
× Ohya, Tomoyuki× Nagatsu, Kotaro× Hanyu, Masayuki× Minegishi, Katsuyuki× Ming-Rong, Zhang× Ohya, Tomoyuki× Nagatsu, Kotaro× Hanyu, Masayuki× Minegishi, Katsuyuki× Ming-Rong, Zhang |
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抄録 | ||||||
内容記述タイプ | Abstract | |||||
内容記述 | Objectives Silver has many attractive radionuclides such as Ag-111 (T1/2 7.45 d / β-) promising candidate for radiotherapy as beta emitter, Ag-105 (T1/2 41.3 d /EC) and Ag-106m (T1/2 8.28 d /EC) for analytical chemistry, Ag-110m (T1/2 250 d /IT, β-) for industrial application, i.e. labeling for silver nanoparticles. Several production routes of these radionuclides from palladium targets using accelerator have been proposed, while few reports of separation have been reported. In this study, we evaluated a separation method for silver nuclides from bulk palladium target with cyclotron (proton or deuteron beam), and recycle method of the target. Methods A 100 mg of natural palladium powder (palladium black) was used as a target of this production study. Irradiation of vertical beam was conducted by NIRS AVF-930 cyclotron with deuteron particles of 20 MeV at 3 – 10 µA for 1 – 3.5 h for production of silver radionuclides or proton of 60 MeV at 3 – 5 µA for 1 – 2 h for research of separation method. Irradiated target was dissolved by conc-HCl with bubbling of chloride gas for 7 – 9 min. After the evaporation of the solution, it was redissolved in 8ml of 1N-HCl and loaded on anion exchange resin (Dowex 1×8, 100-200 mesh, Cl- form, 4g). A byproduct radioactive rhodium was removed by gradual 1 – 2 N HCl. Then, 5N-HCl was loaded to elute the sliver radionuclides, of which the fraction was evaporated to obtain as final product. Conc. HCl was finally loaded to recover the palladium. In the recovery process, the palladium fraction was evaporated and redissolved in 10 ml of 0.1N-HCl. Then, 20 wt% of NaBH4 in ultrapure water (UPW) was added for reducing palladium from chloride form. The reduced palladium was washed four times with UPW by decantation and centrifugation, and was completely dried (recovered palladium). We used HPGe detector (GX1020 Canberra, Meriden, CT) to identify the interested nuclides such as silver, rhodium and palladium on every process. Results The rhodium and palladium radionuclides (Rh-99, 100, 101m, 102m, Pd-100, 101, 103) were found in the irradiated target as radio-byproduct. We successfully separate the sliver nuclides (Ag-105, 106m, 110m) from the target (Fig. 1), where the recovery of silver was > 95 %. The radio elemental purity of any silver nuclides in the sliver fraction was > 99 %, in which both palladium and rhodium radionuclides were not detected. No residue was found in the evaporation of silver fraction (product). The recovery rate of the palladium was about 74 %. Conclusions The separation method presented here has a potential to prepare silver nuclides from a bulk palladium target. An evaluation of the chemical purity and the reducing rate of the palladium are underway. Acknowledgements We would like to thank our cyclotron staff for their operation of NIRS cyclotron and good support. This work was supported by JSPS KAKENHI Grant Number JP17K10386 |
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会議概要(会議名, 開催地, 会期, 主催者等) | ||||||
内容記述タイプ | Other | |||||
内容記述 | ISRS2019 | |||||
発表年月日 | ||||||
日付 | 2019-05-28 | |||||
日付タイプ | Issued |