Rubidium uranium trisulphate: A new chemical assay standard for uranium

Rubidium uranium trisulphate [Rb2U(SO4)(3)] was prepared as a high purity c ompound of uranium in different lots of 250 g each. The compound was charac terised and evaluated by chemical, atomic spectrosopic, infrared, X-ray dif fraction and thermogravimetric methods for its use as a chemical assay stan dard for uranium. The compound is stoichiometric, pure, homogeneous and sta ble in atmospheric conditions. The solubility studies showed that Rb2U(SO4) (3) is easily soluble in mineral acids. An experiment based on Randomised B lock Design was carried out to assign a value to the uranium content in Rb2 U(SO4)(3) from the statistically analysed chemical data. The assigned value of [34.167+/-0.042]% to the uranium content is in close agreement with the theoretical value of 34.152%. Based on these studies, Rb2U(SO4)(3) is reco mmended as a chemical assay standard for uranium.