Analysis of isotope ratio of 232U/233U in irradiated thoria by alpha spectrometry

Indian nuclear program envisages the use of vast deposits of thorium in the country at the second stage for the production of 233U, a fissile material. Among the other isotopes produced, 232U content is of greater significance to fuel reprocessors as its daughter products contribute to high leve1 of gamma dose during reprocessing. Alpha spectrometric method for the isotope ratio of 232U/233U in irradiated thoria has been successfully developed in our laboratory. The report describes the separation procedure followed using Tri-n-Octyl Phosphine Oxide (TOPO) for the purification of uranium from its daughter products and alpha spectrometric method followed for determining 232U content. Alpha spectrum evaluation is also explained in detail. Comparison of spectra from sources prepared prior and after separation forms the method for determining 228Th activity in uranium. The method is simple and fast. (author)