Separation and determination of Pu, Am, and Cm in contaminated soil

The separation of trivalent f-elements such as Am and Cm is challenging due to the similarity in their chemistries. However, these separations are essential in radioanalytical chemistry. In this study, a separation procedure that allows for subsequent quantification of Am and Cm has been developed using commercially available materials. By careful consideration of the eluant, column length, and flow rate, near baseline separation of trace level Am from Cm has been obtained within 5 hours. These results may be modified and applied to capillary electrophoresis for smaller sample size and faster turn around time. For many radioactive samples, isotopic ratios can provide important clues about the provenance of the material. Ratios involving progenitor radionuclides aid in determining the age of a sample. For example, the ingrowth of 240Pu in a solution of 244Cm (t1/2 = 18.10 years) can be used to determine the amount of time that has elapsed since initial purification of the 244Cm. In this study, activity ratios of 244Cm and 240Pu have been determined for three different solutions, one of which is a legacy solution discovered during the closure of a research laboratory. Two of these have been measured by two independent procedures, radioanalytical method and mass spectrometric method. Results from two methods matched within uncertainties, and the age of unknown 244Cm solution has been determined. Pu samples can be classified differently depending on its Pu isotopic ratio (240Pu/239Pu). Also, 239Pu and 240Pu are radiogenic daughters of 243Cm and 244Cm, where the half lives of these are relatively short (29.1 and 18.1 years, respectively). Therefore, when a Pu sample co-exists with Cm source, the Pu isotopic ratio may be altered due to the decay of the parent Cm isotopes. This may cause difficulties of quantifying the isotopic ratio accurately. In this study, soils collected from F-area of Savannah River Site (SRS) have been investigated for Pu, Am, and Cm content as well as Pu isotopic ratio. Results showed that in some cases, the effect of Cm decay on Pu isotopic ratio is significant and the ratio was increased by as much as 100%