A novel approach for the rapid decomposition of Actinide™ resin and its application to measurement of uranium and plutonium in natural waters

A rapid and robust procedure is described for the decomposition of Actinide™ resin permitting the routine application of this resin as a preconcentrator. Although the classical Fe(OH)3 precipitation is effective in scavenging actinides, the need for careful handling to recover the sticky precipitate makes the new method much more attractive. The known difficulty of decomposing Actinide™ resin, which is required prior to the subsequent separation of adsorbed actinides, is innovatively overcome by using a borate fusion attack. This procedure effectively solves the normally encountered problem by safely and speedily decomposing the resin in minutes rather than hours. The alternative and apparently simpler technique of direct ashing of the Actinide™ resin is not used since it leads to a residue that is not readily leachable. The new technique has been incorporated into a procedure for the isolation of Pu and U from natural water samples and their subsequent quantification by alpha spectrometry. The efficiency of loading of the elements onto Actinide™ resin has been tested using both batch and column-based approaches. The integrated method involving Actinide™ resin preconcentration, borate fusion, anion and UTEVA chromatography and electrodeposition provides limits of detection of 0.001 Bq L−1 and chemical recoveries in excess of 80% from groundwater and seawater samples as large as 5 L. Comparative data, presented for the analysis of independently analysed river, borehole and surface run-off waters using both the described procedure and other competing techniques, show very good agreement.