Year
1992
Abstract
We have developed an efficient method for separating and quantitating uranium and plutonium in dissolver solutions using a C18 reversed-phase column, an eluent containing 2-hydroxyisobutyric acid as a complexant, and 5% methanol at pH 4 with ammonium hydroxide. Postcolumn reaction with Arsenazo 111 color reagent is followed by an absorbance measurement at 660 nm. Metal ion interference studies indicated that the combination of the observed separation and the specificity of the Arsenazo III for the actinide and lanthanide ions avoided interferences in the direct quantitation of uranium and plutonium by peak integration. Though peak integration for total metal ion content is probably the most direct analytical approach, the metal ions can be collected after separation for further quantitation or other analyses. A possible application is the separation of uranium and plutonium for isotope dilution assay by thermal ionization mass spectrometry or gamma-ray spectroscopy. Only zirconium, hafnium, tantalum, gallium, and aluminum would be expected to coelute in the region of interest.