Chemistry Reference
In-Depth Information
3
Overview of Recent
Advances in An(III)/
Ln(III) Separation by
Solvent Extraction
Clément Hill
Commissariat à l'Énergie Atomique
Contents
3.1 Introduction .................................................................................................. 120
3.1.1 Why Should Trivalent Actinides Be Separated? .............................. 120
3.1.2 How to Separate Trivalent Actinides? .............................................. 121
3.1.3 Molecular Engineering: Toward a Rational Conception of the
Extractants ........................................................................................ 122
3.2 Fundamental Features of Hydrometallurgy.................................................. 124
3.2.1 Applicable Principles of Solvent Extraction ..................................... 124
3.2.2 Thermodynamics of Solvent Extraction Pertaining to
f
f-Elements ......................................................................................... 126
3.2.2.1 Properties of Trivalent Actinides and Lanthanides ........... 126
3.2.2.2 Solvate Extraction of Trivalent 4
f
and 5
f
Elements ........... 127
3.2.2.3 Cation-exchange Extraction of Trivalent 4
f
and 5
f
Elements............................................................................. 129
3.3 Recent Advances in An(III)/Ln(III) Separation by Solvent-Extraction
Processes....................................................................................................... 130
3.3.1 Two-cycle Processes ......................................................................... 131
3.3.1.1 First Step: An(III) + Ln(III) Separation from the Rest
of the Fission Products....................................................... 131
3.3.1.2 Second Step: An(III)/Ln(III) Separation ........................... 155
3.3.2 One-Cycle Processes: Separation of An(III) from PUREX
Raffinates .......................................................................................... 167
3.3.2.1 The SETFICS Process ....................................................... 167
3.3.2.2 The DIAMEX-SANEX/HDEHP Process ......................... 170
3.4 Conclusion .................................................................................................... 173
Acknowledgment ................................................................................................... 176
References.............................................................................................................. 176
119
