Chromatographic extraction of plutonium and inorganic impurity analysis using ICP-MS and ICP-AES

The purpose of this study was to assess the feasibility of ICP-MS and ICP-AES for the quantitation of 45 target analytes in solutions containing plutonium, and solutions where the plutonium had been removed using anion exchange. The selectivity of the anion exchange resin was also evaluated. High purity plutonium solutions, including a spiked solution were dissolved in triplicate and analyzed by both ICP-MS and ICP-AES, before and after removal of the plutonium matrix. The presence of plutonium appeared to have little effect on recoveries for the ICP-MS technique, whereas twenty-six out of thirty six elements were outside the preferred recovery range of 80-120% for the emission technique. Once the plutonium was removed using a strong anion exchange resin, only 6 elements fell outside the quantitative recovery acceptance window for ICP-AES. Of the target analytes studied, only Ag, Th, Tl, and U appeared to be adsorbed onto the column. These elements are readily determined directly in the plutonium solution by ICP-MS. Elements that must be determined in the extracted sample by ICP-AES are Fe, K, P, and Si. Interelement correction factors were established for the ICP-AES technique and method detection limits were determined for both techniques.