Determination of Pu, Am, U, Th and Sr in marine sediment by extraction chromatography

Three separation methods for the determination of Pu, Am, U, Th and Sr in marine sediment samples based on extraction chromatography are presented. The samples were attacked using an open focused microwave system and the radionuclides were then separated using commercially available resins (TRU Spec, U/TEVA Spec and Sr Spec). The separation methods were tested with synthetic sample solutions containing the five radionuclides with and without interference. To validate the methods, they were also applied to a sediment reference material (IAEA-135). Finally, two of the methods were applied to two sediment samples from the Mediterranean coast of northeast Spain. All the actinides were measured by alpha spectrometry, and 90Sr activity was measured using a liquid scintillation counter. While the recovery of U and Sr was satisfactory in all cases, with values higher than 50 and 75%, respectively, recovery of Pu and Am was more variable and depended on the sample matrix and separation method applied