Plutonium molybdate, precipitation

By chemical analyses, the plutonium molybdate precipitates contains 2 moles of molybdenum per mole of plutonium(IV). Based on thermogravimetry, the plutonium molybdate gradually loses 2 moles of water to form an anhydrous Pu(Mo04)2. Continued heating of this compound results in a loss of Mo03 (>750°C) to yield fee Pu02. X-ray powder diffraction of the carefully air dried plutonium molybdate precipitate provided data that were indexed as having orthorhombic symmetry, with a = 3.34, b = 10.97 and c =... 

Plutonium molybdate precipitated in the absence of Zr is a different structure (isostructural with U(Mo04)2 (16) than the... 

The plutonium-bearing precipitate obtained from nitric acid solutions (containing molybdenum, zirconium and plutonium) gives an X-ray powder diffraction pattern not distinguishable from that of ZrMo207(0H)2(H20)2 precipitated without plutonium. However, since the Pu content is low, the Pu could be present either in the Pu molybdate structure or replacing Zr in the Zr molybdate structure and not be detected in the X-ray patterns. 

In nitric acid solution containing uranium, plutonium, zirconium, molybdenum and other fission products, precipitation of zirconium molybdate occurs preferentially. Solutions containing only zirconium and molybdenum yield the "same" precipitated mater-... 

In the absence of zirconium, a plutonium-molybdenum compound can be precipitated from nitric acid solutions. The presence of zirconium in the same solution is detrimental to formation of this material, as zirconium molybdate is formed preferentially. However, the amount of Pu molybdate solids that form is a function of hydrogen ion concentrations at 1M HN03 or less, solids form but at higher acid concentrations the quantity of precipitate decreases. At 3M HN03 solids are just barely detectable. 

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