Separation of Transplutonium Elements from Neutron Irradiated Americium-241

The isotopes of transplutonium elements were produced by irradiation of 10.5 mg of 241Amo2 in the Japan Materials Testing Reactor during the period May 1970 through June 1971. Transplutonium elements were separated from plutonium, fission products and cladding materials by a combination of precipitation and ion exchange methods. Americium, curium and californium were mutually isolated by ordinary procedure. Plutonium-238–242, americium-241–243 and curium-242–245 were detected in the plutonium, americium and curium fractions, respectively. The ratios of the amounts present of these isotopes were determined by mass spectrometry. It was not possible to identify 249Bk in the berkelium fraction owing to the interference from other, β-ray emitting nuclides. In the californium fraction, both spontaneous fission and α-activities due to 250,262Cf were observed.