Sm isotope composition and Sm/Eu ratio determination in an irradiated 153Eu sample by ion exchange chromatography-quadrupole inductively coupled plasma mass spectrometry combined with double spike isotope dilution technique

Abstract

Within the framework of the research undertaken by the French Atomic Energy Commission on transmutation of long-lived radionuclides, targets of highly enriched actinides and fission products were irradiated in the fast neutron reactor Ph enix. Precise and accurate measurements of the isotopic and elemental composition of the enriched elements are therefore required. In order to obtain the uncertainties of several permil and to reduce handling time and exposure to analyst on radioactive material, the on-line coupling of ion exchange chromatography with quadrupole inductively coupled plasma mass spectrometry has been associated with the technique of the double spike isotope dilution. We present in this paper the results obtained on an irradiated sample of Europium oxide powder (enriched at 99.13% in 153 Eu). After irradiation of around 5 mg of Eu 2 O 3 powder the theoretical calculations predict the formation of several micrograms of gadolinium and samarium isotopes. In relation to the very high activity of the sample after irradiation and the very low quantity of Sm formed, the on-line ion exchange chromatography separation of Gd, Sm and Eu before Sm isotope ratio measurements has been developed for the quantification of the 152 Sm/ 153 Eu ratio. These on-line measurements were associated with the double spike isotope dilution technique after calibration of a 147 Sm/ 151 Eu spike solution. The external reproducibility of Sm isotopic ratios was determined to be around 0.5% (2s) resulting in a final uncertainty on the 152 Sm/ 153 Eu ratio of around 1% (2s). These on-line measurements present therefore a robust and high-throughput alternative to the thermal-ionisation mass spectrometry technique used so far in combination with off-line chromatographic separation, particularly in nuclear applications where characterisation of high activity sample solutions is required. 153 a Commissariat a l'Energie Atomique, DEN/DPC/SECR/LANIE, bât 391,

Radiochemical processing of nuclear-reactor-produced radiolanthanides for medical applications

“…During irradiation, minor amounts of long-lived 154 Eu (t 1/2 = 8.593 y) are formed because of neutron caption of 153 Eu (r th = 312 barn), the daughter isotope of 153 Sm (see example above). The ingrowth of 154 Eu limits the shelf life of the product because the maximum amount of 154 Eu that can be administered to a patient is strictly regulated [90,92]. A maximum of only 0.093 kBq of 154 Eu per MBq of 153 Sm is allowed.…”

Results of the EURAMET.RI(II)- S7.Sm-151 supplementary comparison (EURAMET Project 1292)

“…To perform these analyses, it was necessary to separate the europium from the samarium and gadolinium in order to prevent isobaric interference. This chemical purification was performed at CEA-LANIE in July 2011 by High Performance Liquid Chromatography (HPLC) using 2hydroxy-2-methylbutyric acid (HMB) (Bourgeois et al 2011). The purified fractions were removed off line and analysed by TIMS and/or ICPMS MC.…”

Optimization of double isotope dilution

“…The 148 Nd isotope have the suitable properties for burnup level examination: it is a stable fission product and requires no decay correction, it is not volatile and has no volatile precursors, it is formed exclusively by fission as it has a low neutron capture cross section and is not present in non-irradiated samples. Other applications can be the transmutation yield determination for analytical irradiation examination or to determine the capture integral cross section of different isotopes [4][5][6]. In geochemistry, isotopes ratios like 230 Th/ 238 U or 226 Ra/ 238 U help identifying and characterize the contamination sources [7][8][9].…”