Determination of impurities in plutonium by direct current plasma emission spectroscopy

A Beckman SpectraSpan-VI direct current plasma (DCP) emission spectrometer has been interfaced with a glove box for the quantitative determination of trace element in plutonium-containing samples. This instrument is a rapid-scanning, high-resolution spectrometer that utilizes a modified Czerny-Turner optical design with a 79-groove/mm echelle grating, operated in the 23rd through the 124th order and giving a wavelength range of 180 to 900 nm. The instrument is compact and is readily adaptable for glove box operations. Separation of the actinides from the trace elements of interest is necessary. A tributyl phosphate (TBP) extraction procedure that separates the plutonium from most of the impurity elements has been developed. The trace elements of interest remain in the aqueous phase and the actinides, with the exception of americium, extract into the organic phase. Organic material that dissolves in the aqueous phase does not affect the spectroscopic measurements. The concentration of thorium in plutonium is of great interest, and the authors are developing a separation technique utilizing thenoyltrifluoroacetone