DETERMINATION OF SEPARATED PLUTONIUM, AMERICIUM AND CURIUM IN ENVIRONMENTAL-SAMPLES BY SEQUENTIAL EXTRACTION TECHNIQUES

A simple, reliable and practical radiochemical method for sequential i solation and determination of plutonium, americium and curium in a wid e variety of environmental samples including soils, river sediments an d water was developed. The isotopes determined are: Pu-238, Pu-239,240 , Am-241, Cm-242 and Cm-244. The methods involve leaching of soil or s edimental samples with concentrated nitric acid using a pressure diges tion technique. Subsequent concentration and separation of nuclides of interest from major matrix elements and other interfering alpha-emitt ers are carried out by coprecipitation with ferric hydroxide and solve nt extractions. Sources suitable for alpha-spectrometry are prepared b y electrodeposition from acidic ammonium chloride solution. Pu-242 and Am-243 are used as tracer isotopes of plutonium and americium-curium elements, respectively. Some results of analysis of soils, sediments a nd water are given. The alpha peaks from Pu-238, Pu-239,240 and Pu-242 as well as Am-241, Cm-244, Cm-242 and Am-243 are well resolved. The e ntire analytical procedures for plutonium, americium and curium are co mpleted in less than sixteen hours.