Sequential determination of ⁹⁹Tc and ¹²⁶Sn in radioactive concentrate

Abstract

This paper describes a new sequential method using anion exchange resin, which is commercially available from Eichrom Technologies, Inc., for the determination of 99Tc and 126Sn in nuclear waste samples. For the determination of non-actinide radionuclides in radioactive wastes, several methods have been recently introduced. This method is suitable for the separation of radionuclides 99Tc and 126Sn from acidic solutions. Samples after digestion were directly loaded in 2 mol·dm-3 HCl acid on a cation exchange resin and then on an anion exchange. They were eluted with HNO3. After elution, the eluted fractions were measured either by gamma spectrometry on an HPGe detector or liquid scintillation counter with high chemical recoveries for a short period of time. Activity concentrations of 126Sn were below minimum detectable activity (MDA) for each experiment. A new radioanalytical method for the sequential determination of 99Tc and 126Sn in radioactive concentrates has been developed and successfully applied. The main advantage of the method was the time required for the separation of radionuclides, which was only five hours, and single column separation for the determination of these radionuclides, which makes the method very effective and cheap.

Use of Composite Barrier in Radioactive Waste Repositories

“…79 Se and 126 Sn are remarkable radionuclides in the waste packages because they are long half-live fission products and radiologically harmful in the spent nuclear fuel [9][10][11]. The fission efficiency for 126 Sn and 79 Se are 0.0236% and 0.04%, respectively [11,12]. The half-life of 126 Sn is 2.35x10 5 and it is a dangerous beta (max = 252 keV) and gamma (87.6, 86.94 or 64.3 keV) emitter by thermal neutrons although it has a relatively low production of about 0.056% is a fission product.…”

“…The half-life of 126 Sn is 2.35x10 5 and it is a dangerous beta (max = 252 keV) and gamma (87.6, 86.94 or 64.3 keV) emitter by thermal neutrons although it has a relatively low production of about 0.056% is a fission product. The halflife of 79 Se is 65000 years and it is potentially dangerous for beta radiation (max = 0.056 MeV) [12]. According to the Belgian deep geological repository, 79 Se is seemed to the main contributor to the activity release.…”

Radiochemical Methodologies Applied to Analytical Characterization of Low and Intermediate Level Wastes from Nuclear Power Plants

“…The aim of this work is to present a review about radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes and present new research perspectives covering new methodologies for LLW and ILW characterization. More recently, the number of publications on this topic has been great, involving innovative methodologies and analytical techniques [4][5][6][7].…”