Zirconium transport dynamics in the Purex solvent extraction process

Abstract The primary objective of this study was to develop and validate experimental and mathematical procedures that can be used to determine the fundamental mechanisms of the Purex (plutonium and uranium) extraction process. The mechanisms of this solvent extraction process have been established by classical chemical engineering principles. In the past, modeling of transport phenomena for the solvent extraction of spent nuclear fuel by the Purex process has typically (1) relied solely on diffusion, (2) relied solely on chemical reaction, (3) combined diffusion and chemical reaction in a semiempirical fashion, or (4) combined diffusion and chemical reaction in a nonclassical chemical engineering manner. This study was conducted with the single Purex species, aqueous Zr4+, to simplify the chemistry and modeling mathematics. The validated procedures and model are applicable to most all Purex species.