solvent extraction, a high performance technology

Solvent extraction, a high performance

technology

Marie-Christine Charbonnel, Binh Dinh, Christian Sorel, Jean-Marc Adnet, Manuel Miguirditchian, Jean-Philippe Dancausse

| PAGE 1CEA | 17 DECEMBRE 2014Nuclear Energy DivisionRadioChemistry & Processes DepartmentCEA Marcoule, France

| PAGE 2

APPLICATIONS OF LIQUID LIQUID EXTRACTION (SX)

When distillation not possible (economical or technical origin)

High boiling point component

Low concentration of components

Thermal sensitivity (food products, fragrances as orange oil

or pepermint oil)

Separation of compounds with similarproperties

Same boiling point of components,

Same chemical properties (Ta-Nb, rare earths along

the series, uranium-vanadium, hafmium-zirconium,

carboxylic and sulfonic acids…)

High purity of final productsNuclear industry (uranium before enrichment)

Food-grade phosphoric acid

Rare earths (optical and electronic field)

Expensive metal catalyst

Hostile environment with necessity of low maintenance

Nuclear industry (reprocessing of nuclear fuel)

Mineral chemistry

Nuclear industry

Hydrometallurgy(copper,

PMG*,.…)

Recycling (rare earths)

Organic chemistry

Pharmaceutical and fine

chemistry

Petroleum industry

Food industry

*Platinum Group Metal: liquid liquid extraction comes back !(review of R. Grant. Johnson Mattheys, Isec14, Septembre 2014)

phenol or aniline fromwaste waters

Other ways after leaching: precipitation. separation by ion exchange

CEA | 17 DECEMBRE 2014

| PAGE 3

PRINCIPLE OF LIQUID LIQUID EXTRACTION: SEPARATION AND PURIFICATION

FeedM1 + M2

Strippingsolution

StrippingSolution

M1

RaffinateM2

Extractant(s)Diluent Solvent treatment

EXTRACTION BACK-EXTRACTION

Speciation in organic phase.

thermodynamics

Extraction by a solvent of a selected component (metallic ion. molecule. group of elements.…etc)

Mainly counter-current process, Several stages Back extraction to recover the component

before the finishing operations

La Hague. Areva

Main advantages• Ability to operate in a continuous countercurrent mode,• Multistage mode (to achieve high separation factors),• High yield of recovery,• Regeneration of solvent.

Pu4+

M1M2

M2


aq

org

VV

E MD

M'

MM/M' D

DSF

very low related energySF = 100 (extG)M/M’=-11kJ/mol

One stage Process flow sheet

finalproduct

initialproduct

impurity

impurity

MDF

)1(/)1()(c/)(c 1aqM

aqM EE n

finalinitial

aqM

orgM

M ccD

With DM =10and Vorg/Vaq=11 stage – 10% in raffinate2 stages – 1% in raffinate3 stages – 0.1% in raffinate

AN INTEGRATED APPROACH:THE KEY OF A SUCCESFULL INDUSTRIAL SOLUTION

Importance of each step• to optimize the process conditions• to take into account the side steps

Molecularengineering

Industrialextrapolation

usingsimulation

Processchemistry

Lab scaleprocess

qualification

Processmodelling

Apparatus development

| PAGE 4CEA | 17 DECEMBRE 2014




usingsimulation

Processchemistry

Lab scaleprocess

qualification

Processmodelling




• High affinity towards the target element,• Reversibility,• High selectivity / other solutes and

impurities

Performances

• Stability (hydrolysis in acidic media. oxydation.…) and low influence of degradation products,• Solubility of the extractant (low in the aqueous phase, high in the organic phase even in presence of the target element)

Effects of media

• Kinetics of reactions and hydrodynamicproperties (viscosity, densities, interfacialtensions.…) compatible with industrialcontactors,• Cost of the reactants and synthesis,• Chemical hazards and respect of REACH regulations

Industrialisation

• Good recovaribility of reactants,• Incinerable reactants (CHON)

Environmental footprint

APPROACH TO DESIGN A NEW CHEMICAL SYSTEM

Molecule family selection

Molecule synthesis

Performance checks(DM – FSM/M’ and organic solubility)

Stru

ctur

e-ac

tivity

rela

tions

Molecule selection

Bibliography

Chemical knowledge

Process specifications

Moleculeavailability

PO

OO

O

O

NO

O

N

N

NN N

NN

N

N





usingsimulation

Processchemistry

Lab scaleprocess

qualification

Processmodelling



CEA | 17 DECEMBRE 2014 | PAGE 7

| PAGE 8

MOLECULAR APPROACH TO DESCRIBE THE SOLUTIONS

X-rayDiffraction

(single crystal)

X-rayDiffraction

(single crystal)

CalorimetryCalorimetry

Mass Spectrometry

Mass Spectrometry

SpectroscopyIR/Ramanvisible UV Laser

FluorescenceX Absorption *

SpectroscopyIR/Ramanvisible UV Laser

FluorescenceX Absorption *

Nuclear Magnetic

Resonance

Nuclear Magnetic

Resonance

MolecularModellingMolecularModelling

ELECTRONICSTRUCTUREELECTRONICSTRUCTUREKINETICSKINETICS

THERMODYNAMICSTHERMODYNAMICSCOORDINATIONCOORDINATION

SPECIATIONSPECIATION

-0,01

0,04

0,09

0,14

0,19

0,24

0,29

0,34

0,39

0,44

425 435 445 455 465 475 485 495 505

00,20,50,811,522,534610

Acquisition of basic data(speciation, thermodynamic constants.…etc):

entrance of modelling process


Chemistry of extraction

30

0

20

40

60

80

100

120

0 20 40 60 80 100 120 140 160 180 200

[U(VI)]aq. g/L

[U[V

I)]o

rg.

g/L

[HNO3] aq.

0

0,020,1

0,20,3

0,5

12

34,5

HNO3 4.5 M

No HNO3

[U(V

I)]or

g

aqM

orgM

M c

cD

bXM

LMX

nnbm

nb m

nb

LXMLMX

.. . L K=c ext

orgM

)][1]([i

ii

m

nbMXMLMXc

)1( nborgaqL

LMXnLLC

| PAGE 9

1/ Isotherms of extraction

3/ Stability constants

UV-visible, NMR, microcalorimetry, TRLIFS…

Mm+ + b X- + n L MXbLn

2/ Overall extraction

Mass spectrometry

FTIR, Raman, NMR, TRLIFS, EXAFS

Slopeanalysis DM

[U(VI)]aq

M'

MM/M' D

DSF


4/ Kinetics of extraction

AN INTEGRATED APPROACH:THE KEY OF A SUCCESFULL INDUSTRIALSOLUTION



usingsimulation

Processchemistry

Lab scaleprocess

qualification

Processmodelling




AN IMPROVED APPROACH: USING SIMULATION TOOLS

Process flowsheet

Model/processvalidation

Integration and validation tests

Models/fondamental dataBatch data

Molecularcharacterization

Codes for processsimulation

Distribution of speciesKinetics of reactionsMass transferHeat transferHydrodynamics


SOME PROCESS COMMON SPECIFICATION DETAILS

• Limit the stages at each step

Simplicity

• Tolerance to cross-phase entrainment,• tolerance to presence of solids particles,• tolerance to process upsets

Robustness

• Limit the building (size/height)• Choice of the best contactor

Compact

• Continuous long-term operation• Frequent start-stop operation

Flexibility

• Solvent inventory• in-process volume holdup of solvent

Safety

Economy





usingsimulation

Processchemistry

Lab scaleprocess

qualification

Processmodelling




| PAGE 14

QUALIFICATION OF PROCESSES

Different scales and loops to test the processes withsurrogate or genuine solutions

Counter-current tests in lab-scale mixer-settlers

scale 1/10000

Tests in continuous contactors(pulsed colomns)

scale 1/1000

Tests in continuous contactorswith solvent treatment

scale 1/10





usingsimulation

Processchemistry

Lab scaleprocess

qualification

Processmodelling




Different contactors availableMixer settlers, different columns (packed, agitated), centrifugal contactors

Columns prefered in first cycles (possibility of presence of solid particles, shorter time of contact,…)

From Lab scale to industrial scaleDifferent hydrodynamic conditions (in-depth know-out about flows)

• characterize phase flows for each scale (merging of mathematical modeling)• Modelize the interfacial area, the droplet size, …(link also with the importance of

kinetics)

CONCEPTION OF INDUSTRIAL APPARATUS FOR EXTRACTION

Couette effect column Small diameter pulsed column

Industrial pulsed columnLaboratory


1/ The PUREX Process

2/ The extraction of U from ores

3/ The minor actinides separation

Examples of liquid liquid qualified

processes in the nuclear field

| PAGE 17


|

CONTEXT OF THE STUDY IN THE FRENCH FUEL CYCLE

Natural uranium

Ultimate disposal3% of spent fuel0.5% of natural uranium mined

Pure naturaluranium

Refining

Conversion

Enrichment UO2 fuel

MOx fuel

Storage

Fuel fabrication

Thermal-neutron PWRs

Recycled uranium

Plutonium

Storage

Storage

Waste

Spent UO2 fuel

U-235 enriched uranium

U-235 depleted uranium

Reprocessing plants

Ore extraction

Spent MOx fuel

Ores U. Niger

La Hague

Malvesi/Pierrelatte

Bure


CHEMICAL ELEMENTSIN NUCLEAR SPENT FUELS

ACTINIDES

ACTIVATION PRODUCTS

FISSION PRODUCTS1

H3

Li11

Na19

K37

Rb55

Cs

87

Fr

4

Be12

Mg20

Ca38

Sr56

Ba

88

Ra

21

Sc39

Y

Ln

An

22

Ti40

Zr72

Hf

104

Rf

23

V41

Nb73

Ta

105

Db

24

Cr42

Mo74

W

106

Sb

25

Mn43

Tc75

Re

107

Bh

26

Fe44

Ru76

Os

108

Hs

27

Co45

Rh77

Ir

109

Mt

28

Ni46

Pd78

Pt

29

Cu47

Ag79

Au

30

Zn48

Cd80

Hg

5

B13

Al31

Ga49

In81

Tl

6

C14

Si32

Ge50

Sn82

Pb

7

N15

P33

As51

Sb83

Bi

8

O16

S34

Se52

Te84

Po

9

F17

Cl35

Br53

I85

At57

La

89

Ac

58

Ce

90

Th

59

Pr

91

Pa

60

Nd

92

U

61

Pm

93

Np

62

Sm

94

Pu

63

Eu

95

Am

64

Gd

96

Cm

65

Tb

97

Bk

66

Dy

98

Cf

67

Ho

99

Es

68

Er

100

Fm

69

Tm

101

Md

70

Yb

102

No

71

Lu

103

Lr

2

He10

Ne18

Ar36

Kr54

Xe86

Rn

ACTINIDES

LANTHANIDES

U 955 kgPu 9.6 kgMinors actinides 0.78 kg

Lanthanides: 10.2 kg

PFs (without Ln):24 kg

For 1 t of spent fuel (standard fuel , irradiation : 3 years)


| PAGE 20

The PUREX process (1)


Industrialextrapolation using

simulationn

Processchemistry

Lab scaleprocess

qualification

Processmodelling


Process chemistryUO2

2+ + 2 NO3- + 2 TBPorg (UO2(NO3)2 TBP2)org

Pu4+ + 4 NO3- + 2TBPorg (Pu(NO3)4TBP2)org

Process modelling

PUREX (Plutonium, Uranium Refining by EXtraction)

Y. Marcus and A.S. Kertes, Ion Exchange and Solvent Extraction of Metal Complexes, John Wiley & Sons, (1969), p.953

Affi

nity

(DM

)

U(VI) and Pu(IV) wellextracted

Extraction threshold

M3+ lowextraction

Process flowsheet

Model/processvalidation

Integration and validation tests

La Hague reprocessing plant

Facility conception

Industrial feedback integration

Safety and exploitation books

sensitivityanalysis

Robustness Rules

Models/fondamental data

Batch data

Molecularcharacterization

Codes for processsimulation

DistributionKineticsMass transferHeat transferHydrodynamics

HNO3 3.5MCEA | 17 DECEMBRE 2014

| PAGE 21

The PUREX process (2)

Very significant feedbackUSA : 1950 (Savannah, Handford)

GB : 1953 (Windscale)1994 (Sellafield THORP)

FRANCE : 1958 ( Marcoule)From 1967 ( La Hague, differentworkshops)

> 25 000 tHM LWR Spentnuclear fuel reprocessed in La Hague plants

RobustnessEfficiency

Fuel Dissolution EXTRACTION

TBP

FP +Minor An

U

PuPu

Vitrification

Uranyle nitrate:

950 kg (> 99.5%)

GBq (DF GBq

Plutonium nitrate: > 9.68 kg (> 99.8%)

GBq (DF


Question from the French laws about the nuclear waste management (1991-2006) The management of the Minor Actinide Np?Management today: After dissolution of the fuel: presence of Np(V)/Np(VI) in HNO3

| PAGE 22

EVOLUTION INSIDE THE PUREX PROCESS: NEPTUNIUM MANAGEMENT (1)

Np(V)

Np(IV)Np(VI)

DNp


Np4+ + 4 NO3- + 2 TBP Np(NO3)4, 2 TBP

NpO22+ + 2 NO3

- + 2 TBP NpO2 (NO3)2, 2 TBP

| PAGE 23

Model adjustment (with kinetics of Np)

Lab scale test with representative conditions of La Hague (15kg of UOX fuel, extractors withthe same technology, flowsheet similar as the first cycles)

EVOLUTION INSIDE THE PUREX PROCESS: NEPTUNIUM MANAGEMENT (2)

With minor modifications of compositions (when chemical system, modelling and hydrodynamic well known) easy to recover additional elements in a selected flow



usingsimulationn

Processchemistry

Lab scaleprocess

qualification

Processmodelling


More than 99% with uranium

Flexibility


EXTRACTION OF URANIUM FROM PHOSPHATES ROCKS (1)

Question from industry: improve the classical processProcess today: from 1952 to 1998 at Oak Ridge - 20 kT of U3O8

Following limitations: DU(VI) not high enough to improve the process compactness DFe(III) slightly too high: formation of insoluble cruds (iron

hydroxides) in U stripping step

Acidic ligandNeutral

oxygen donor

SYNERGY

Chemical system C(mol/L) DU SFU/Fe

TOPO + HDEHP (1:4) 0.1 0.8 200

DEHCNPB 0.1 70 8 700DEHCNPB Di(éthyl-2 hexyl) carbamoyle nonyle butyle phosphonate

extraction U extraction Fe



usingsimulationn

Processchemistry

Lab scaleprocess

qualification

Processmodelling


Patent WO 2013/167516 Al

Design of new molecules Difficulty to improve both data DU and SFU/Fe After different tests, combination of the 2 functions in a same molecule

| PAGE 24CEA | 17 DECEMBRE 2014 | PAGE 24

Mechanism of extraction (isotherms and molecular approach) and extraction modelling

Design of a flowsheet with 3 main steps tested on a genuine industrial phosphoricacid solution (Counter-current test runned in mixer-settlers)

| PAGE 25

EXTRACTION OF URANIUM FROM PHOSPHATES ROCKS (2)

UO22+ + 2 (HY)2 UO2Y2(HY)2 + 2 H+

Fe3+ + 1.5 (HY)2 FeY3 + 3 H+

Recovery of U > 91% (U losses (raffinate and

recycled solvant) ≤ 5 mg/L)

Concentration of U from 0.12 to 5.6 g/L

High DF of U from Fe and other impurities

Fe/U = 0.043% < ASTM specifications (0.15%)

good agreement between experimental and calculated concentrations profiles whichvalidates the extraction model

Increased efficiencyfrom molecular design


THIRD EXAMPLE : MINOR ACTINIDES RECOVERY FROM

PUREX RAFFINATE

CEA | 17 DECEMBRE 2014| PAGE 26

VARIOUS MINOR ACTINIDES PARTITIONING PROCESSES

PUREXUPu

---

An(III)/Ln(III) separation(r SANEX)

An(III) + Ln(III)coextraction(DIAMEX)

-

Am selective Stripping(EXAm)

GANEX 1

GANEX 2

U

Pu Np Am Cm

Am Cm

Am Cm

An(III) selective Stripping (i-SANEX)

An(III) selective Extraction

(1c-SANEX)

Am Cm

Homogeneous recycling= grouped separation

GANEX

Heterogeneous recycling= enhanced partitioning

DIAMEX/SANEX

Am

U, Np, Pu, Am,

Cm

TMA

U Pu

FP

U

T

U Pu MA

FP

U

U



usingsimulationn

Processchemistry

Lab scaleprocess

qualification

Processmodelling



A demanding challenge: separation of actinides from fission products (Ln and An which have very similar chemical properties)

A sophisticated partitioning chemistry under highly radioactive conditions

Steps methodology applied in wide cooperation framework (numerous EU projects as ACSEPT, SACSESS)Explorative R&D and in-depths understanding of actual mechanismsBatch lab experiments and process designDemonstration experiments on actual SNF (some kgs)

MINOR ACTINIDES PARTITIONING METHODOLOGY

Scale : 1/100 à 1/1000

A few hundredsof new molecules

Lanthanides (Ln)10,2 kg

Actinides (An)U 955 kgPu 9,6 kgMineurs 0,8 kg

Conditions Low quantities Extrem conditions

High acidity High radioactivityNumerous elements

(cLntot ~ 50 × (cAm +cCm))

High recovery rate99,9 % for actinides with high purity


Design of molecules

Qualification with a demonstrative run (november 2005)

| PAGE 29

Coextraction of Ln and An(III) - Diamex process

Selection from• chemical properties (high

affinity because chelate withAn and Ln(III))

• ‘CHON’ composition

MALONAMIDESMALONAMIDES

RN

R’

O

CHR’

R’

R’’

N

O N

O

N

C H 3

O

C H 3 C 2 H 4

C 8 H 17C 8 H 17

OC 6 H 13

DMDOHEMA

Compromise betweenaffinity, solubility and stability

HNO3

Am ~ 0.015 %Cm < 0.002 %

extraction(CP) (CP)

-

HEDTA

HNO3H2C2O4HEDTA

HNO3

Fission ProductRaffinate

extractionAn+ Ln

(CP)

ScrubbingFP(CP)

Am, Cm, Ln> 99.9%

Back-extraction An-Ln (MS)

NaOHHEDTA

Solvent Treatment(ECRAN)

0.65 MDMDOHEMA/TPH

PUREX raffinate15 kg genuine fuel

Ln ~ 2.5 g/LAm ~ 150 mg/LCm ~ 15 mg/LV ~ 1 L/h

4 m highPulsed columns

HNO3H2C2O4HEDTA

extraction(CP)

extractionAn+ Ln

(CP)

DIAMEXProductionAm, Cm, Ln

Efficiency with representative feed and contactorsCEA | 17 DECEMBRE 2014

Monoamide DEHiBACompromise between U(VI) extraction and U(VI)/Pu(IV) selectivity (SF~60)

HDEHPDMDOHEMA

+ HEDTA / citric acid

N

O

NCH3

C8H17

CH

NCH3

C8H17

O O

C2H4

OC6H13

PO

OHO

ON

O

O

ON

OH

OH

OHOH

Efficiency demonstrated in

Atalantein 2008

> 99.9% U>99.9% Pu+AMs

THE MA HOMOGENEOUS RECYCLING PROCESSTHE GROUPED ACTINIDE GANEX CONCEPT


NO

N

O O

OO

OHOP

Design of the chemical systemsFrom knowledge of previous processes, proposition of the following chemical system to obtain the separation from the Purex raffinate

Stripping of Am with HEDTA + citric acid (pH 3-4)

ChemistryVarious species identified by combination of spectroscopic techn ics: LnTEDGAn

3+ and AnTEDGAn3+

ModellingTo simulate the behavior of the 15 extractiblescations in the first extraction step 1,

62 complexes considered

THE SOLE-AM RECYCLING: EXAM PROCESS (1)

Organic solvent Aqueous phase

0,01

0,1

1

10

100

0,94 0,96 0,98 1 1,02 1,04

ionic radius (A)

DM

no TEDGA

with TEDGA

M as tracesLn mmol

Sm

Nd

Pr

Ce

La

Eu

CmAm

SFAm/Cm = 1.6

SFAm/Cm = 2.3

-0,01

0,04

0,09

0,14

0,19

0,24

0,29

0,34

0,39

0,44

425 435 445 455 465 475 485 495 505

00,20,50,811,522,534610

TEDGATEDGA.HNO3

HNO3M(TEDGA)

M3+

M(TEDGA)2-3TEDGA

(TEDGA)(D)x(HP)y.HNO3 M(TEDGA)(D)x(HP)y

(D)x(HP)y.HNO3 M(D)x(HP)y

324.5

395.7

300 400 500 600 700 800 m/z0.0

0.2

0.4

0.6

0.8

5x10Intens.

L3Am3+

L2Am(NO3)2+

LAm(NO3)2+L2Am(NO3)2

+

CEA | 17 DECEMBRE 2014 | PAGE 31

Labscale qualification

THE SOLE-AM RECYCLING: EXAM PROCESS (2)

LS'(NaOH)

BX : SolventLX : Solvent

LS(Citric, pH 3)

BP(Am)

AF' (TEDGA, H 2 O)

CLn(Nd, Ce, Pr, La, Fe)

CX(TEDGA, HNO 3 , H 2 C 2 O 4 )

BX(HEDTA, Citric acid, pH 3)

Am stripping

Ln strippingCW : Solvent

Mo stripping

45°C

Ln scrubbing

EXTRACTION

AX : Solvent(DMDOHEMA, HDEHP, TPH)

30°C

SCRUBBING

AS(TEDGA, HNO 3 )

AW(Cm, Eu, Sm, Gd)

LW(Pd, Mo, Ru)

AF : PUREX raffinate(Am, Cm, PF)

% Am = 1%

% Am = 0.7%

% Am = 98.3%DFAm/Cm= 500DFAm/Nd= 340

Good recovery of Am with a decontamination factor vs Cm and Ln

MD02 (AS)

MD01 (AX)

In 68 stages of lab-scale mixer-settlersFeed : genuine PUREX raffinate54 h running with genuine feed

32 stages

8 stages

8 stages (Mo)20 stages

Challenging separation efficiencywith representative feed


High performances in solvent extraction obtained in the nuclear field could beconsidered as illustration of deep potential technic Efficient partitioning processes (recovery yield >99% and decontamination

factors>99%) Challenging separations (chemical similar properties) Severe industrial conditions (robustness of equipments with limited maintenance,

avoid criticity conditions, presence of radiations, environmental regulations) Flexibility (easy to add some stages, to change composition if objectives change) Importance of modelisation to predict the scale-up effect and to test processes at

different scales Hydrodynamics in different contactors and scale-up effects Predict the behavior in case of transitory states Side problems to discover

Knowledge obtained during the study of these separations The chemistry of various elements (presence in the nuclear spent fuels and from ores)

Rare earths (separation from actinides and along the series), Tc, Mo, Fe, Pd, … Chemical engeenering Analytical chemistry (ANL)

Possibilities to transfer knowledge to design efficient solid-liquid separations, more convenient in some cases

| PAGE 33

CONCLUSION

THANK YOU FOR YOUR ATTENTION

| PAGE 34


solvent extraction, a high performance technology

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