Ion Exchange Process for the Recovery of PU²³⁸ from Irradiated NP²³⁷

Abstract

A practical process is described for the recovery of Pu23' product and unconverted Np23, from Np 237 oxide compacts irradiated in nuclear reactors at the Savannah River Plant. Three cycles of anion exchange are required to separate the Np and Pu from each other and produce nitrate solutions of each element which are

Evaluation of Aqueous and Powder Processing Techniques for Production of Pu-238-Fueled General Purpose Heat Sources

“…A similar hydroxide precipitate process uses magnesium hydroxide to react with Pu nitrate solution 4 ; however, for Pu-238 heat source applications, precipitation with ammonium hydroxide is preferred to minimize introduction of cationic impurities. Once the oxide had been sized, the powder was sintered at 1200°C and oxygen isotope exchanged with 16 O 2 to reduce neutron emission. This powder was then hot pressed into approximately 1.5-in.…”

“…Valves and flowmeters are used to regulate gas flows. Alumina baffles are placed at both ends of the alumina tubes to moderate the flow of the Ar-H 2 16 O required.…”

“…The pellet is stored overnight so that it will be reoxidized to PuO 2.0 or nearly so before the dimensioning activities. Similarly, the Ar-H 2 16 O gas flow is started before the furnace is turned on to ensure a stoichiometry of PuO 2.0 before the pellet is sintered. The use of Ar-H 2 16 O flow gas, of course, precludes back exchange of the material and subsequent increased neutron emission rates.…”

Trilaurylamine Extraction of Neptunium and Plutonium from Purex Process Waste

“…in the absence of an aqueous phase for 4to 72-hour periods. In further experiments equal volumes of 0.3M TLAdiluent solutions and either 4 HNOs or synthetic 1WW solution containing 0.02 mole per liter of hydrazine were in contact (with agitation) continuously at 25°to 30°C. for as long as 72 hours while in the irradiation facility.…”

Gas Formation in Anion Exchange Resin Beds

“…After a short interval to allow reduction of the actinides, the solution is heated to 55°C for 30 minutes. Only a small fraction of the ferrous ion is normally required to reduce the actinides; therefore, the heat treatment oxidizes the major portion of the remaining ferrous ion: 13 , 41 ( 1) When one liter of 0.05M Fe2+ is oxidized, 0.025 mol of HN0 2 is produced, 0.025 mol of sulfamic acid is consumed, and 560 cc (STP) of nitrogen gas are produced: ( 2) Approximately the predicted quantity of gas was released during the heating of synthetic process solutions with efficient agitation. Mass spectrometric analysis confirmed that the gas was mostly nitrogen.…”