Most process design models used for PUREX separations are primarily concerned with the separation of plutonium from uranium. The purpose of this study was the development of a process model for PUREX solvent extraction that includes fission products as well as actinides based upon simple theoretical principles. Theoretical such that applicability can extend to most species of interest for fuel reprocessing and simple enough to be user friendly for the researcher’s process design of separation systems. Existing PUREX design codes are often difficult to use for the independent researcher because of (1) limited access to the executable codes, (2) lack of user-friendly guidance for application of the code, and/or (3) inability to adapt the code for their specific application. The REDDIC model developed for this study is based upon a modified form of the chemical reaction originally put forth by Seaborg and Loveland. This original equation was adapted by the author to more fully consider a heterogeneous (multi-phase) reaction. When REDDIC is applied to counter-current equilibrium solvent extraction it enables the individual researcher to develop a conceptual process design that can be used to assess the feasibility and cost of a variety of scenarios for separating spent fuel radionuclides for reuse or permanent waste storage. Uranium, neptunium, zirconium and ruthenium extraction have been used as examples to demonstrate model applicability.
