title: Liquid-liquid extraction separation and sequential determination of plutonium and americium in environmental samples by alpha-spectrometry.
abstract: A procedure is described by which plutonium and americium can be determined in environmental samples. The sample is leached with nitric acid and hydrogen peroxide, and the two elements are co-precipitated with ferric hydroxide and calcium oxalate. The calcium oxalate is incinerated at 450 degrees and the ash is dissolved in nitric acid. Plutonium is extracted with tri-n-octylamine solution in xylene from 4M nitric acid and stripped with ammonium iodide/hydrochloric acid. Americium is extracted with thenoyltrifluoroacetone solution in xylene at pH 4 together with rare-earth elements and stripped with 1M nitric acid. Americium and the rare-earth elements thus separated are sorbed on Dowex 1 x 4 resin from 1M nitric acid in 93% methanol, the rare-earth elements are eluted with 0.1M hydrochloric acid/0.5M ammonium thiocyanate/80% methanol and the americium is finally eluted with 1.5M hydrochloric acid in 86% methanol. Plutonium and americium in each fraction are electro-deposited and determined by alpha-spectrometry. Overall average recoveries are 81% for plutonium and 59% for americium.
authors.affiliation: Environmental Research Laboratory II, Japan Atomic Energy Research Institute, Tokai-mura, Ibaraki-ken 319-11, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Sekine
authors.forename: T
authors.initials: T
authors.lastname: Imai
authors.forename: A
authors.initials: A
authors.lastname: Kasai