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DIRECTION DE L’ENERGIE NUCLEAIRE
COMMISSARIAT A L'ENERGIE ATOMIQUE
DEN/SAC/DIR/CM/02/263
SACLAY, LE 7 MAI 2002
PRESENTATION OF THE WORK DONE IN THE FIELD OF PARTITIONING IN
THE FRAME OF THE 5 th FWP OF THE EUROPEAN UNION
DURING THE ADOPT MEETING HELD AT ITU ON MARCH, 14, 2002
by
Charles MADIC
DEN/SAC/DIR
CEA/Saclay
DIRECTION DE l’ENERGIE NUCLEAIRE,
SAC/DIR, Bt 523, CEA/Saclay, 91191 Gif-s-Yvette, France
Charles MADIC
TEL : 33. (0) 1.69.08.82.07 - FAX : 33. ( 0) 1.69.08.79.90
E-mail : charles.madic@cea.fr
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PARTNEW
(Contract FIKW-CT-2000-00087)
I.
INTRODUCTION
The aim of the research program PARTNEW is to define solvent extraction processes
for the partitioning of the minor actinides, Am and Cm, from the high active raffinate (HAR)
or high active concentrate (HAC) issuing from the reprocessing of UOx or MOx fuels by the
PUREX process.
II.
WORK PROGRAM AND LABORATORIES INVOLVED
The work is divided into eight work packages (WP) corresponding to three research
domains: A/ co-extraction of trivalent actinides (An(III)) and lanthanides (Ln(III)) from acidic
HARs or HACs (DIAMEX process), B/ An(III)/Ln(III) group separation from acidic feeds
(SANEX processes), C/ Am(III)/Cm(III) separation:
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WP1: DIAMEX basic studies,
WP2: DIAMEX process studies,
WP3: SANEX basic studies with polydendate nitrogen ligands,
WP4: SANEX process development with polydendate nitrogen ligands,
WP5: SANEX basic studies with di-thiophosphinic acid synergistic mixtures,
WP6: SANEX process development studies with di-thiophosphinic acid
synergistic mixtures,
WP7: SANEX basic and process studies with new S-bearing ligands,
WP8: Am(III)/Cm(III) separation basic studies.
A total of eleven European laboratories are involved in the research including :
1/ CEA/DEN/Marcoule (France), co-ordinator,
2/ CEA/DSM/Saclay (France),
3/ The University of Reading, Reading (UK),
4/ Chalmers University of Technology , Göteborg, (Sweden),
5/ ITU, Karlsruhe (Germany),
6/ ENEA/Saluggia, (Italy),
7/ Politechnico di Milano, Milano (Italy),
8/ INE/FZ, Karlsruhe, (Germany),
9/ IRS/FZJ, Jülich, (Germany),
10/ CIEMAT, Madrid (Spain)
11/ Universidad Autonoma de Madrid, Madrid (Spain).
III.
MAIN ACHIEVEMENTS OBTAINED AT MID-TERM
The main achievements of the research carried out during the first 18 months of the
contract are briefly summarised below.

WP1. In the field of DIAMEX basic studies the main achievements obtained are the
following:
 Bis-malonamide ligands have been synthesised at UAM. Some molecules present
interesting An(III) and Ln(III) extraction properties,
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 Thermodynamics of the extraction of An(III) and Ln(III) nitrates by malonamides was
studied at CEA/Marcoule, using the van t’Hoff method with M(III) distribution ratios
and by micro-calorimetry,
 Kinetics of extraction of Am(III) and Ln(III) nitrates by DMDBTDMA has been
studied at FZK,
 NMR spectroscopy and molecular modelling were used to precise the structure of
solvates formed between Ln(III) nitrates and diamide bearing an ether O within the
central group of the molecule,
 The supramolecular organisation of the solvates formed between malonamides and the
following solutes : (i) nitric acid, (ii) Ln(III) nitrates, (iii) uranyl nitrate, was studied
by CEA (Saclay and Marcoule) using different techniques, including X-rays and
neutrons small angle scattering.

WP2. The main achievements obtained in the field of DIAMEX process development are
the following:
 A total of 1.4 kg of spent MOX fuel was reprocessed at ITU in order to generate
sufficient volume of HAR for the preparation of HAC,
 Experimental conditions for the treatment of a HAC (6x) by the DIAMEX process
have been determined. This work is being conducted in collaboration between ENEA,
PoliMi, FZJ and ITU,
 The radiolytic and hydrolytic degradation of the diamide DMDOHEMA was studied
at CEA/Marcoule. Then, efficient solvent clean-up procedures of the degraded solvent
were defined,
 A test of the DIAMEX process using a genuine HAR has been conducted successfully
at CEA/Marcoule. This demonstrates the feasibility of the DIAMEX process based on
the use of DMDOHEMA for the partitioning of Am and Cm from HAR. During this
test, it was shown that solvent recycling is possible while maintaining good separation
performances.

WP3. The main achievements for this WP are as follows:
 New N-bearing ligands have been prepared at Reading, including bis-oxazolepyridine. Some of these molecules exhibit interesting An(III)/Ln(III) separation
properties,
 Numerous progress have been obtained in the understanding of the complexation
properties of N-bearing ligands by molecular modelling studies, performed both at
Reading and CEA/Marcoule,
 ESI-MS spectroscopy (CEA), NMR spectroscopy (CEA) and crystal structure
determinations (Reading) were methods used to understand better the interaction
between N-bearing ligands and Ln(III) ions,
 The thermodynamics of complexation by N-bearing ligands were the subject of
numerous studies at CEA and Chalmers. At Chalmers a model was defined to predict
the effect of the diluent on the affinity of synergistic mixtures vs Am(III) or Ln(III)
ions. At CEA, the thermodynamic parameters of the complexation of the entire series
of Ln(III) by ADPTZ were determined. Moreover, microcalorimetry was used for the
study of the complexation of Ln(III) ions by BTP ligands. The main driving force for
the reactions was found to be the enthalpy,
 The kinetics of extraction of Am(III) an Ln(III) nitrates by n-Pr-BTP was studied at
INE-FZK. It was shown that the extraction rate of Am(III) is limited by a chemical
reaction located at the interface between the aqueous and organic liquids.
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
WP4. The main results obtained are the following:
 A hot test of the SANEX-III process, using i-Pr-BTP extractant was carried out
successfully at CEA/Marcoule in June 2001. Nevertheless, the extractant used was
found a bit degraded, so a need for a more robust BTP ligands still exists,
 A test of the SANEX-III process using n-Pr-BTP and implemented with hollow-fibremodules (HFM) was performed at INE-FZK on synthetic {An(III)+Ln(III)}mixtures.
Very promising results were obtained, and the experimental results are in fair
agreement with the calculated data performed using the computer model defined.

WP5. The main results are as follows:
 New bis-substituted-di-thiophosphinic acids were prepared at FZJ and their extraction
properties vs An(III) and Ln(III) tested in synergistic combinations with organophosphates or phosphine oxides. Some new systems exhibit large An(III)/Ln(III)
separation factors.

WP6. The main results are the following:
 A test of the ALINA SANEX-(III) process for An(III)/Ln(III) separation was
successfully conducted on synthetic spiked solution at FZJ using a bank of miniature
centrifugal extractors.
 A test of the same ALINA SANEX-(III) process was performed also successfully at
INE using a HFM. Here also, experimental and calculated data were in good
agreement.

WP7.
 The only noticeable result is this WP concerns the synthesis of a thiomalonamide at
UAM.
WP8
 A very important discovery has been made at FZJ. It was shown that a synergistic
mixture of bis-(chlorophenyl)-di-thiophosphinic acid + TEHP permit to discriminate
between Am(III) and Cm(III) from acidic feeds, with separation factor SF Am/Cm close
to 10. This is a breakthrough in this field.

IV.
CONCLUSIONS
The research within the PARTNEW collaboration was very active during the first 18
months of the contract. The scientific feasibility of the DIAMEX process for treating HAR
and that of the SANEX-BTP process for An(III)/Ln(III) separation were demonstrated.
Numerous basic data were also obtained which consolidate the understanding of the
extracting properties of the various extractants studied.
PYROREP
( FIKW-CT-2000-00049)
I.
INTRODUCTION
The aim of the research program PYROREP is to determine the practicalities of
separating uranium, plutonium and minor actinides (MA) from a spent fuel or an irradiated
target using pyrochemistry. Several options have been selected, including: (i) molten chloride
or molten fluoride salt media, (ii) separation using molten salt / metal exchange processes,
(iii) separation by electrolysis.
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II. WORK PROGRAM AND LABORATORIES INVOLVED
The project comprises three work packages (WP) including:
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WP1. Separation. Two methods are studied: (i) salt/metal extraction, (ii)
electrorefining. The media studied are molten chloride and molten fluoride salts,
WP2. Subsidiary process steps will be assessed such as: (i) salt decontamination vs
traces of actinides in order to minimise losses, (ii) material selection and testing.
Suitable construction materials compatible with molten fluoride media will be
selected and tested,
WP3. Waste and system studies: (i) leach tests will be carried out on inactive
sodalite, which is the waste form selected for conditioning spent salt baths, (ii) the
performances of various pyrochemical processes will be compared, (iii) modelling
and preliminary economic assessments of the processes will be performed.
A total of ten laboratories are involved in the research, including:
1/ CEA/DEN/Marcoule, (France), co-ordinator,
2/ CIEMAT, Madrid, (Spain), with University of Valladolid (UVA), as sub-contractor,
3/ ENEA, Trisaia and Casaccia (Italy), with PoliMi (Milano), as sub-contractor,
4/ ITU, Karlsruhe, (Germany),
5/ CRIEPI, (Japan),
6/ BNFL, (UK), with AEA-Harwell, as sub-contractor,
7/ NRI, (Czech Republic).
II.
MAIN ACHIEVEMENTS OBTAINED AT MID-TERM
The main achievements of the research carried out during the first 18 months of the contract
are briefly summarised below.

WP1. In the field of the separations, the main achievements obtained are the following:
 Separation by salt/metal extraction (CEA): the separation of the actinides (An) are
done by their reduction into metals. The distribution of Pu, Am and Ce (a lanthanide,
Ln) between AlCu (60/40 wt%) fused alloy and various Lif-AlF3 salt melts were
determined. From these data it is concluded that An/Ln separation could not be
optimised by changing the melt fluoro-acidity,
 Separation by electrolysis from fluoride media (CEA). A lab-scale electrolyser was
designed and constructed. The first electrochemical experiments concerned Nd in
various fluoride melts.
 Separation by electrolysis (CIEMAT & UVA). The work done here is to apply
electrochemical methods for the separation of elements contained within a spent fuel
surrogate (SIMFUEL). Numerous work items are included in this work concerning
technology and basic chemistry. As examples of the main conclusions reached todate, on can cite: (i) W and Mo metals are suitable for making electrodes for work in
LiCl-KCl melts, (ii) liquid Cd cathode was studied, and Ln-Cd alloy formation was
observed, (iii) the efficiencies of La and Ce electrodeposition were found to be close
to 80-90%.
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 Design, construction and testing of an electrorefiner unit under inactive conditions
(ENEA). This work, initiated at Trisaia will be transferred to Brasimone.
 Reprocessing of metal fuel (ITU & CRIEPI). At the ITU, in a joint effort with
CRIEPI, a small-scale installation for pyrochemical reprocessing of metallic spent fuel
has been set-up. It includes an electrorefiner equipped with: (i) a solid cathode for U
separation, (ii) a liquid Cd cathode for Pu and MA extraction. Numerous tests have
been conducted involving U and Pu.
 Process study: separation of Am by electrorefining (ITU & CRIEPI). The aim of the
work is to demonstrate the feasibility of the separation of MAs from Lns. The
techniques and procedures for basic parameter determinations have been optimised
and numerous experiments were performed.
 Study of electrolytic separation from molten fluoride salt (NRI). An electrolyser has
been designed and constructed successfully. It is able to work with 2 or 3 electrodes.
Experiments using these two configurations were carried out for studying
electrochemical separations. Moreover, work was done for the selection of the
composition of the fluoride melt.
 Assessment of controlling parameters (BNFL). Work was done here to assess the
parameters (stirring, current, voltage) that can be used for the control of the
electrorefiner (chloride melt). Several solid cathodes and two reference electrodes
were studied. For liquid Cd cathode, a « pluger » has been commissioned in order to
improve the use of this peculiar electrode.
 Decontamination factors for U and Pu from MAs (BNFL). Experiments using U and
Pu have been conducted. U metal deposited on a Fe cathode, from a chloride bath
containing an U/Pu mixture (4/1), was found to contain less than 1/14000 of Pu.
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WP2. Subsidiary steps. The main achievements in this field are as follows:
 Conversion of spent fuels to halide form (CIEMAT). The objective of this work is to
determine the stability of the compounds and the reaction rates when direct
chlorination of the oxide fuel (SIMFUEL) is performed. Solubilization studies of Ln
oxides and oxohalides have been carried out in the eutectic LiCl-KCl at 450 °C. It was
observed that HCl is a convenient gas for chlorination. Chlorination experiments of
UO2 were also successfully performed.
 Material and equipment selection for molten fluoride salts (NRI). Numerous materials
have been studied, including: (i) BN, (ii) silica glass, (iii) alumina, (iv) pure Ni, (v)
Inconel 686. Recommendations for material selection will be proposed at the end of
the research.
 Salt decontamination (BNFL). Different methods (electrolytic and chemical) for the
elimination of MAs from the spent salts are studied. An experimental set-up has been
installed in a glove-box for these studies.
WP3. Waste and system studies.
 Preparation of sodalite samples (ENEA & PoliMi). In case of pyrochemical processes
to be implemented in chloride melt, the spent salt is expected to be conditioned in
sodalite. Synthesis of sodalite has been carried out using an hydrothermal process.
Preparation of pellets for leaching tests, to be carried out by CEA, is under way.
 System studies. Some prospective nuclear scenarios have been selected. For example,
NRI focuses on a specific scenario based on the use of molten salt reactors associated
with reprocessing in fluoride media. Literature research is also underway in this field
to consolidate the knowledge of pyrometallurgy applied to nuclear fuel cycles.
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IV.
CONCLUSIONS
The work carried out during the first 18 months of the PYROREP program is in-line
with the contract. Good collaboration between the different partners is observed and one can
expect that most of the goals defined for the research will be reached.
CALIXPART
( FIKW-CT-2000-0088)
I.
INTRODUCTION
The aim of the research program CALIXPART is to design, to synthesise and to study
ligands, belonging mostly to the class of functionalized calixarenes, able to selectively extract
the trivalent minor americium (Am) and curium (Cm) from the high active acidic raffinate
(HAR) issuing from the reprocessing of nuclear spent fuel.
II.
WORK PROGRAM AND LABORATORIES INVOLVED
The work research program has been divided into 8 work packages (WP) including:
 WP1. Synthesis of non macrocyclic ligands,
 WP2. Synthesis of new macrocycles with one type of ligating functions,
 WP3. Synthesis of new macrocycles with mixed types of ligating functions,
 WP4. Extraction and complexation experiments,
 WP5. Basic studies,
 WP6. Modelling,
 WP7. Implementation of new extractants,
 WP8. Development studies on promising compounds.
A total of nine European laboratories are involved in the research, including:
1/ CEA/DEN/ Cadarache, (France), co-ordinator,
2/ Université de Liège, (Belgium),
3/ Université Louis Pasteur, Strasbourg, (France),
4/ Johannes Gutenberg-Universität, Mainz, (Germany),
5/ Micromod Partikeltechnologie GmbH, (Germany),
6/ Università di Parma, (Italy),
7/ Universidad Autonoma de Madrid, Madrid, (Spain),
8/ University of Twente, Twente, (Neederlands),
9/ CIEMAT, Madrid, (Spain).
Recently, CALIXPART was enlarged to include a Czech team composed of 3 partners
(Academy of Sciences of CR, Katchem and NRI).
The organisation of the work between the laboratories involved is shown below.
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SYNTHESIS
MAINZ ; LIEGE ; PARMA ; TWENTE ; MADRID
Calixarenes ; Cavitands ; Cyclotriveratrylenes; Dendrimers
SCREENING
CEA CAD
Extraction tests on Ln(III) and An(III)
Selection of promising compounds
BASIC DATA
TESTS
PARMA ; LIEGE
X-ray ; NMR ; luminescence
ECPM STRASBOURG
Stoichiometry ; thermodynamic data
MODELLING
ULP STRASBOURG
MD and QM simulations
Selection of confirmed compounds
III.
IMPLEMENTATION OF EXTRACTANTS
DEVELOPMENT STUDIES
CEA CAD ; MICROMOD
Membranes ; Microparticles
CEA CAD ; CEA VALRHO ; CIEMAT
radiolysis; hot tests ; flow sheet process
MAIN ACHIEVEMENTS OBTAINED AT MID-TERM
The main achievements of the research carried out during the first 18 months of the
contract are the following:
 WP1. Synthesis of non macrocyclic ligands was focused on ligands bearing the following
ligating functions: CMPO and di-thiophosphinic acid. This includes the synthesis of
dendrimers. The main achievements obtained are the following:
 Syntheses of bi- and tridendate di-thiophosphinic acids and of mixed phosphine
oxide - di-thiophosphinic acids were carried out at Liège. But as these ligands are
unstable, this work was stopped,
 Dendrimers (up to the 5th generation) bearing the CMPO moiety were prepared at
Mainz. The extraction of Am(III) and Eu(III) by the CMPO-dendimers was studied
and gave interesting results. Consequently, magnetic and non-magnetic particles
coated with these CMPO-dendrimers will be prepared in a near future,

WP2. Synthesis of new macrocycles with one type of ligating functions. The main
achievements obtained to-date are the following:
 Synthesis of calix[4]arenes with diketone (TTA) pending ligands were
successfully prepared at Parma,
 At Twente, calix[4]arenes bearing thiourea or COSAN units were prepared. The
affinity of these molecules for Am(III) and Eu(III) was found poor.
 Calix[6]arenes, in the cone conformation and bearing malonamide ligating groups,
were synthesised at Madrid. The affinity of these extractants for Am(III) and
Ln(III) nitrates was studied for different aqueous nitric acid concentrations. No
Am/Ln separation was observed, which is quite normal for O-bearing ligands.
 At Parma, calix[n]arenes bearing picolinamide and thiopicolinamide ligating
groups have been prepared. Extraction tests with the ligands used in synergistic
combination with Br-Cosan were performed. SFAm/Eu of ~ 10 was obtained for the
ligand PAR-8.
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 At Liège, calix[4]arenes bearing thiopyrazolones moieties were prepared.
Unfortunately, no Am/Eu separation was observed during their extraction with
these ligands.

WP3. Synthesis of new macrocycles with mixed types of ligating functions. The main
achievements are as follows:
 Calix[4]arenes substituted at the wide rim. A mixture of CMPO and amide
moieties were grafted on the same calix[4]arene platform at Mainz. Interesting
extraction results were obtained with the ligand MZ18, bearing 2 ethylamide
moieties and 2 CMPO moieties. Am/Eu separation factor close to 10 was obtained
for a 10-3 mol/L MZ18 organic solution and a 1 mol/L nitric acid feed.
 Calix[4]arenes substituted at the narrow rim. Numerous ligands of this type have
been prepared at Mainz and Parma, but none of them exhibit interesting selective
affinity for Am(III).

WP5. Basic studies. The most important results obtained in this field are the following:
 Crystallography and NMR are the most important experimental techniques used to
understand better the complexing and extracting properties of the ligands. At
Liège, paramagnetic dipolar NMR shifts and relaxation times were measured to
determine the structures of the complexes formed between Ln(III) ions and new
ligands in solution.

WP6. Modelling. Numerous systems have been modelled and a better understanding of
the interactions between trivalent metal ions and the ligating functions used in the
preparation of new calix ligands has been obtained. The work done includes:
 M3+ interactions with amides, urea, diamides and thia analogues in the gas phase,
 MD simulations in dry chloroform and at a liquid-liquid interface and QM
optimizations in the gas phase.

WP8. Development studies on promising compounds.
 The main work done in this WP concerns the study of the stability of selected
ligands under high irradiation. The work is done at CIEMAT in the NAYADE
irradiation facility. Preliminary experiments were conducted on TBP and
CYANEX 301 extractants, leading to the definition of the irradiation and
analytical procedures.
IV.
CONCLUSIONS
The work carried out during the first half of the CALIXPART contract was important.
A tremendous amount of synthesis work was done and numerous molecules were prepared,
tested and studied. We hope in the future the discovery of ligands with interesting An(III)
extraction and separation properties by the CALIXPART team of scientists.