Radiochemical methods analysis of U and Th: metrological and geochemical applications

A present conference describes the methods for determination of U and thorium isotopes in natural samples and the study of their adsorption by the new activated adsorbents. The first part was carried out by using alpha spectrometry. The thin alpha sources were prepared by chemical electroplating of U and Th. Both elements were separated by using the ion-exchanges chromatography before their deposition. The dissolution of major solid sample was made by using alkaline fusion by LiB4O7 and LiBO2. The proposed methods have been applied for U, Th isotopes determination in the sedimentary rock: phosphate and its derivatives products and in the extracted solution from the black shale. The second part of the work was focused on the study of U, Th isotopes adsorption by new oil shale activated adsorbents.