Direct Selective Extraction of Actinides(III) from PUREX Raffinate Using a Mixture of CyMe_4-BTBP and TODGA as 1-cycle SANEX Solvent PART II: Flow-sheet Design for a Counter-Current Centrifugal Contactor Demonstration Process

Abstract

The 1-cycle SANEX process has been developed as a simplification of the DIAMEX+SANEX concept by reducing the required process steps from two to one. The goal is to separate americium(III) and curium(III) directly from a PUREX raffinate which is very complicated due to the complex composition of the solution. In previous work, extensive batch studies have been carried out using an organic phase comprising CyMe₄-BTBP and TODGA. This system has now been further developed towards a counter-current centrifugal contactor test using a synthetic PUREX raffinate solution. Single stage experiments were carried out to study the extraction kinetics and a 32 stage flow-sheet is proposed with calculated recoveries for some key elements. The calculations show that americium is recovered in the product with only small amounts of impurities. A demonstration process following the designed flow-sheet is expected to fulfill all the requirements for this complicated separation.

Keywords:

• SANEX
• CyMe₄-BTBP
• TODGA
• solvent extraction
• minor actinides

ACKNOWLEDGMENTS

Financial support for this research was provided by the European Commission (project ACSEPT – Contract № FP7-CP-2007-211 267). Frank Lewis, University of Reading, is greatly acknowledged for providing CyMe₄-BTBP.