Determination of 126 Sn in radioactive waste using TEVA Ò resin and gamma spectrometry Silvia Dulanska ´ • Ja ´n Bilohus ˇc ˇin • Boris Remenec • L’ubomi 9r Ma ´tel • L’ubica Dara ´z ˇova ´ Received: 30 September 2014 Ó Akade ´miai Kiado ´, Budapest, Hungary 2015 Abstract A new method employing TEVA Ò resin from Eichrom Technologies for determination of 126 Sn in nu- clear waste was developed. The influence of stable tin carrier and hydrochloric acid concentration on the separa- tion and chemical yield of 113 Sn was tested. The method is suitable for the separation of 126 Sn isotope from hy- drochloric acid solution. For the determination of 126 Sn from radioactive waste samples, tin was first precipitated with ammonium sulfide in 0.5 mol L -1 HCl, dissolved in concentrated HCl, loaded in 1 mol L -1 HCl on TEVA Ò resin column and eluted with 2 mol L -1 HNO 3 acid. Eluted tin fraction was directly measured by gamma spectrometry on HPGe detector. Keywords 126 Sn separation Á TEVA Ò resin Á Nuclear waste Introduction The operation of nuclear power plants generates large quantities of radioactive materials or waste, which need to be characterized for their decommissioning or final dis- posal in radioactive waste repositories. Nuclear operators in Slovak Republik must declare 19 critical radionuclides ( 14 C, 90 Sr, 99 Tc, 129 I, 137 Cs, 94 Nb, 126 Sn, 151 Sm, 41 Ca, 59 Ni, 63 Ni, 79 Se, 93 Mo, 93 Zr, 107 Pd, 60 Co, 239, 240 Pu, 238 Pu and 241 Am) in all radioactive waste before storage in the regional radwaste repository in Mochovce. Long-lived ra- dionuclides created in reactor’s active zone such as 239 Pu, 94 Nb, 129 I, 93 Zr, 126 Sn, 99 Tc and others will represent the majority of the activity inventory of the radioactive waste in the future. While radionuclides such as 137 Cs or 60 Co can be easily measured by gamma spectroscopy the alpha, beta or low abundance gamma emitters such as 126 Sn have to be separated individually from the matrix and other radionu- clides before measurement. In our previous papers methods for determination of 239 Pu [1], 93 Zr [2], 94 Nb [3] and 90 Sr [4] isotopes in various types of nuclear waste originated from Slovak nuclear power plants were presented. Our next work was focused on the development of a method for 126 Sn determination in radioactive evaporator concentrate. 126 Sn is a long-lived beta (b max = 252 keV), gamma (87.6, 86.9 or 64.3 keV) emitting radionuclide with a half-life of 2.35 9 10 5 years. As a fission product it has relatively low yield approximately 0.056 % by thermal neutrons. The main natural production mechanism of 126 Sn is through spontaneous fission of 238 U and the abundance ratio of the 126 Sn/Sn in the earth’s crust is less than 10 -14 . Artificially produced 126 Sn has entered our environment through nu- clear activities and may also be released from reprocessing plants what may locally lead to enhanced 126 Sn concen- trations [5]. Kinard et al. [6] attempted to isolate 126 Sn with ion- exchange procedure from specific sludge and to use gamma analysis to count the 126 Sb (T 1/2 = 12.4 days) daughter in secular equilibrium. This procedure required a large de- contamination factor from 137 Cs. In the separation proce- dure, a stable Sn carrier is added, the solution was ion- exchanged from 9 mol L -1 HCl and Sn eluted with 0.1 mol L -1 HCl. The separated sample was analyzed by direct liquid scintillation counting of 126 Sn or by gamma analysis after the 126 Sb has grown in. S. Dulanska ´(&) Á J. Bilohus ˇc ˇin Á B. Remenec Á L. Ma ´tel Á L. Dara ´z ˇova ´ Department of Nuclear Chemistry, Faculty of Natural Sciences, Comenius University, Mlynska Dolina, 842 15 Bratislava, Slovakia e-mail: dulanska@fns.uniba.sk 123 J Radioanal Nucl Chem DOI 10.1007/s10967-015-3969-9