Separation of tervalent lanthanides from actinides by extraction chromatography

Abstract

A procedure is described for the removal of milligram amounts of lanthanides from the tervalent actinides. The routine application of an earlier procedure resulted in low americium yields and poor resolution of the ) spectrum, mainly due to inadequate removal of neodymium. The reported procedure offers many significant improvements and involves prepurification of the lanthanide-actinide fraction by precipitation as a hydroxide, removal of the lanthanides from the tervalent actinides by extraction on a column of bis(2-ethylhexyl)-phosphoric acid sorbed on Teflon powder, and carrying the actinides directly from the eluate on about 50 ..mu..g of cerium fluoride for ) spectrometry. The actinide recovery from a mixture of 5 mg of cerium, 3 mg of lanthanum, and 2 mg of neodymium was 86% for californium and 96% for americium and curium, with less than 10 ..mu..g of the neodymium remaining. The average overall recovery of americium from routine analysis of 131 soil samples was 84 +/- 6%. 4 figures, 1 table.