Nitrate Anion Exchange in Pu-238 Aqueous Scrap Recovery Opoerations

摘要

Strong base, nitrate anion exchange (IX) is crucial to the purification of ²³⁸Pu solution feedstocks with gross levels of impurities. This paper discusses the work involved in bench scale experiments to optimize the nitrate anion exchange process. In particular, results are presented of experiments conducted to a) demonstrate that high levels of impurities can be separated from ²³⁸Pu solutions via nitrate anion exchange and, b) work out chemical pretreatment methodology to adjust and maintain < sup>238Pu in the IV oxidation state to optimize the Pu(IV)-hexanitrato anionic complex sorption to Reillex-HPQ resin. Additional experiments performed to determine the best chemical treatment methodology to enhance recovery of sorbed Pu from the resin, and VIS-NIR absorption studies to determine the steady state equilibrium of Pu(IV), Pu(III), and Pu(VI) in nitric acid are discussed.