153Sm, 166Ho, 177Lu production in VVR-SM

Abstract

153 Sm, 166 Ho, and 177 Lu and their compounds are finding increasing applications in science and technology, especially in medicine. Tagged compounds of these radionuclides can be used in diagnostics and cancer treatment [1][2][3].Isotopes of rare-earth elements are produced mainly by irradiating in a reactor targets consisting of natural or enriched compounds. During irradiation other isotopes (impurities) are produced together with the desired isotope.This article presents experimental results on the production of 153 Sm, 166 Ho, and 177 Lu in VVR-SM at the Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan and purification of these isotopes using the liquid extractants TBP (tri-(n-butyl) phosphate), D2EHPA (di-(2-ethylhexyl) orthophosphoric acid), TOA (tri-n-octylamine), and MDOA (methyl-n-dioctylamine).Chemical compound of Sm, Ho, Yb, and Lu, primarily oxides but in some cases sulfate salts, were irradiated. For this, a weighed amount of a compound in a hermetically sealed ampoule was placed in an aluminum block-container and irradiated by a neutron flux in a vertical channel of the reactor. After being removed from the reactor the irradiated samples were left standing in order to cool down. Then the ampoules were opened and transferred into thermostable chemical laboratory ware for radiochemical processing.Radioactive indicators and extraction with liquid extractants were used to investigate the interphase distribution of the radionuclides.Radiometric measurements were performed with an NP-424L four-channel gamma-spectrometer (Hungary) with an ND-420L scintillation sensor. The γ-spectrum was analyzed in a measurement facility at the Institute of Nuclear Physics and the radionuclides were identified by their analytical γ-line.The distribution coefficients of the radionuclides in the experimental systems were calculated from the relationfor static conditions and the relationfor dynamic conditions. Here [Me] or and [Me] aq are the metal concentrations in the organic and aqueous phases, respectively; V max is the solution volume corresponding to the maximum of the chromatographic peak; and, V 0 and V eff are the free and effective volumes of the chromatographic column, respectively.

The radio-europium impurities in [153Sm]-EDTMP production: a review of isolation methods

“…Another study with the experimental results of the production and purification samarium and europium isotopes, using liquid extractors D2EHPA di-(2-ethylhexyl) orthophosphoric acid (D2EHPA), TOA and methyl-n-dioctylamine (MDOA) has also been presented by Nishanov et al . [47]. According to the radionuclide distribution coefficients of radionuclides in Fig.…”

“…Distribution coefficients of Sm and europium versus the LiNO 3 concentration with TOA purification [47]. …”

“…Nevertheless, by implementing a wellplanned separation method, the challenges mentioned above can be handled and a 153 Sm radionuclide with a higher quality can be achieved. Accordingly, over the past years, some articles discussed the europium separation and purification from the 153 Sm target [39,40,[44][45][46][47]. The important challenge of samarium/europium isolation is the great similarity of the chemical and physical properties of neighboring radiolanthanides.…”

“…This method can also be applied for efficient removal of Eu 2+ from any other lanthanide (Ln 3+ ). In another study, Nishonov et al [47] demonstrated the purification of the samarium from impurities produced in a water-water reactor-SM nuclear reactor with two extraction systems, tri-n-octylamine (TOA)-LiNO 3 and di-2-etilgekhsil-ortofosfor acid (D2EGFK)-HCL. The TOA system is anion-exchanger and radionuclides of rare earth elements, such as La, Ce, Pr, Nd, samarium, europium and Gd can form single charged anion complexes of [Ln (NO 3 ) 4 ] or [Ln (NO 3 ) 5 ] 2 .…”

“…Anion-exchange chromatography is when the stationary phase is positively charged and negatively charged molecules are loaded to be attracted to it [58,59]. In chromatography, the solutions used are mostly dilute, and as a result, the eluting method Distribution coefficients of Sm and europium versus the LiNO 3 concentration with TOA purification [47]. is more commonly used, and very satisfactory separations are often obtained.…”