Abstract
Heterogeneous oxidation has been utilized for one-step conversion of metallic W to WO3 at approximately 750 °C in a stream of air, with simultaneous separation of W from Re and Os impurities which are coproduced during the long neutron irradiation of the W target (approximately 50 days). The freshly produced WO3 is readily soluble in a base for use in a 188W/188Re biomedical generator. The metallic tungsten target, in the form of small pellets (4×3 mm diameter×height), was prepared by cold pressing W powder at approximately 3 tons/cm2. Sintering (vacuum annealing) the pellets at 1200-1400 °C, under 1-10 μTorr pressure provided good mechanical strength. Analysis of the black residue, which is typically encountered in the dissolution of neutron-irradiated WO3 targets, indicated that 186W and 187Re were the main constituents. Further, the specific activity of insoluble 188W in the residue was approximately 200 times smaller than that of soluble 188W.
Original language | English |
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Pages (from-to) | 3169-3172 |
Number of pages | 4 |
Journal | Industrial and Engineering Chemistry Research |
Volume | 39 |
Issue number | 9 |
DOIs | |
State | Published - 2000 |