SPECTROCHEMICAL ANALYSIS OF 'FISSIUM' FOR CERIUM AND LANTHANUM
"Fissium" is a synthetic spent plutonium-rich reactor fuel which has a nominal wt.% composition of 2.5 Fe, 0.7 Ce, 1.3 La, 0.7 Mo, 1.3 Ru, and 0.8 Zr. It is used as a stand-in for irradiated fuel in the study of pyrometallurgical methods of treatment for the removal of fission products. To evaluate the cesium and lanthanum contents of the fuel alloy, as well as the by-products of this treatment, a spectrochemical method was developed which has a coefficient of variation of 6% and comparable accuracy when amounts ranging from 40 to 200 - g are determined. The recommended procedure involves the following steps: dissolution of the solid sample in HCl, HNO/sub 3/, or HClO/sub 4/; oxidation of plutonium to the hexavalent state with HClO/sub 4/; separation of cesium and lanthanum from plutonium and other elements by precipitating them as the fluorides along with europium, which is added as a coprecipitant; conversion to an HCl medium; spectrographic analysis of the sample and a set of standards, utilizing spark excitation with copper electrodes; and photometry of suitable spectral lines, including those of the internal standard, europium, on a calibrated emulsion to evaluate the concentrations by conventional means. After dissolution of the sample, the succeeding steps can be readily completed for six samples in duplicate by the expenditure of 8 man-hours of work. The least practical amount of element to process is 10 - g. A factorial experiment involving cerium, lanthanum, neodymium, plutonium, and other fissium- element concentrations indicated that bias existed for cerium and lanthanum deteminations at the 20- - g level of each, but not at the 50- - g and higher levels. No significant difference was observed when the relative proportions of cerium and lanthanum were varied tenfold in the absence of neodymium. Erratic and incomplete recovery of cerium was noted if the concentration of HCIO/sub 4/ was less than 1N during the F/sup -/ precipitation; HCI0/sub 4/ in concentrations up to 3N gave satisfactory results. Processing of standards, both with and without the fission elements, by the recommended procedure yields data which are not significantly different spectrographically from those observed for unprocessed aliquants. (auth)
- Research Organization:
- Los Alamos Scientific Lab., N. Mex.
- NSA Number:
- NSA-15-008753
- OSTI ID:
- 4102792
- Journal Information:
- Talanta (England), Vol. Vol: 6; Other Information: Orig. Receipt Date: 31-DEC-61
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
Annual Progress Report for the Period July 1961 Through June 1962
SEPARATION AND ANALYSIS OF BASTNAESITE RARE EARTHS