Irradiated tellurium targets were purified by precipitation from 6M HCl solution using 1,10-phenanthroline. The effect of molar ratio of the reactants (initial 1,10-phenanthroline:Te molar ratio) on the precipitation yield of radiotellurium was studied. It was found that, >99% of radiotellurium has been taken up by the precipitate formed with the initial 2 phenanthroline:1Te molar ratio along with different decontamination ratios from the other cross-radiocontaminants; >= 99.9% of Zn-65, 97.7 +/- 1.2% of Se-75, >= 99.9% Ag-110m, and 95.4 +/- 2.5% of Sb-124. Traces of Cr-51, Mn-54, Fe-59, and Co-60 have been detected only in the supernatant after the precipitation process. Un-irradiated tellurium was precipitated with 1,10-phenanthroline under the same conditions with the initial 2 phenanthroline:1Te molar ratio and, then, the precipitate formed was characterized by IR spectroscopy and thermal analysis. The Most probable chemical composition of this precipitate was [Te(phen)(2)Cl-4]center dot 3 center dot 4H(2)O. (C) 2008 Elsevier B.V. All rights reserved.