Determination of impurities in nuclear‐grade uranium compounds by x‐ray fluorescence spectrometry

Abstract

A method in described for the simultaneous determination of trace concentrations of Ca, Cr, Cu, Fe, Mn, Ni, Mo, As, Zn, Co, Th, V and Ti in nuclear‐grade uranium oxides or other uranium compounds by x‐ray fluorescence spectrometry without the use of chemical treatment. The limits of detection are Mo 25, As 40, Cu 5, Ni 29, Co 17, Fe 5, Mn 30, Cr 8, Th 7, Zn 5, V 52, Ti 10 and Ca 80 ppm. Samples are prepared in the form of double‐layer pellets with starch as a binding agent. Standards are prepared in a U3O8 matrix, which is more chemically stable than other uranium oxides. The dynamic ranges of the calibration graphs are very large because, for all impurity elements, they are linear over three orders of magnitude of concentration. The method is fast, since it requires no chemical treatment and only limited manipulations. The method has good precision for the impurity elements.

Determinations of low atomic number elements in real uranium oxide samples using vacuum chamber total reflection x-ray fluorescence

“…are important constituents of nuclear fuel and trace determinations of various impurities in such materials is important for their quality assurance for their various applications in electricity generation by using nuclear reactors, as presence of elemental impurities in nuclear fuels above the specified limits can have detrimental effects the mechanical as well as nuclear properties of the material. [5,6] We have developed TXRF method for trace determinations of most of the medium and high Z elements in uranium and thorium matrices in our earlier studies. [7,8] There are limited trace element determination techniques for the determination of low atomic number elements.…”