Year
2014
Abstract
Particle sizes and morphologies of 238PuO2 obtained from aqueous processing may differ, according to the details of the processing. Particle sizes, in particular, may vary, and particle sizes determine parameters of handling and processing such as the batch sizes that are allowed, in order to satisfy constraints imposed by the Safety Basis on material that may be exposed to hypothetical catastrophic scenarios: Material At Risk (MAR.) Understanding variations in particle size as functions of variations in processing assures that no batch falls outside the range assumed in calculation of the MAR, and also improves the understanding of the relationship between the strength of the final ceramic and the particulate that composes that ceramic. Particle sizes arising from two unrelated aqueous processing facilities are examined and compared to reveal similarities and differences. Differences may be anticipated in oxide derived from Pu(III) oxalate precipitation and Pu(IV) oxalate precipitation, and from other variations in details of aqueous purification of PuO2. Observed differences are insignificant in determination of MAR, but reflect morphological variations in oxide from different aqueous processing schemes.