Optimization of extraction chromatography separations of trace levels of actinides with ICP-MS detection

Abstract

The separation of trace level actinides has been evaluated on extraction chromatography columns. Detection of the actinides was achieved through the use of an inductively coupled plasma MS (ICP-MS). The columns that we tested were prepared from a commercial TRU resin. The separation of the actinides was optimized for several parameters including particle size, column length, packing pressure, and eluent flow rate. We also examined the possibility of reducing or eliminating oxalic acid in the eluents in order to improve the performance of the mass spectrometer. We were able to separate a mixture of five actinides ((232)Th,( 238)U,( 237)Np, (239)Pu,( 243)Am) in less than 4 min. This work has application to rapid bioassay as well as for automated separations of actinide materials.