Plutonium oxide systems vaporization

Our conceptual flowsheet for further decontamination of plutonium dioxide indicates oxidation of Pu02 with a nitrate melt containing peroxide. A plutonate species should form with this treatment. If formed, we expect the plutonate to be soluble in the melt upon addition of nitric-acid vapor. If this supposition is correct, then the plutonium could probably be recovered similar to uranium. Whether a plutonate or Pu02 would be obtained from the thermal decomposition of a soluble plutonate species is unknown for this system. 

The binary systems actually and potentially important as nuclear fuel include oxides, carbides, nitrides, phosphides, and sulfides of uranium, plutonium, and thorium. An increasing amount of detailed information is becoming available on the phase equilibria of these compounds, but the relations existing between the composition (especially nonstoichiometric) and the vapor pressure (or activity) of each component are known only for a limited number of systems. 

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