Actinide stripping by a hydrophilic BTP ligand in aqueous ... · Actinide stripping by a hydrophilic BTP ligand in aqueous HNO 3 from TODGA containing organic phase. L. Steczek1,

1

Actinide stripping by a hydrophilic BTP ligandin aqueous HNO3 from TODGA containingorganic phase.

L. Steczek1, J. Narbutt1, M. Rejnis1, P. Moisy2, M. Ch. Charbonnel2

1 Institute of Nuclear Chemistry and Technology, 2 Alternative Energies and Atomic Energy Commission

First SACSESS International Workshop: ‘Towards safe and optimised separation processes, a challenge for nuclear

scientists’ 22-24.04.2015 Warsaw

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Bibliography ‐ Aromatic poly‐N‐dentate ligands

The simplest aromatic poly-N-dentate ligand is 2,2'-bipyridil

Affinity to protonate nitrogen atoms decreases in the order:

> >

| PAGE 3

The Choice of Selected ligand Lipophilic poly-N-nitrogen ligands are broadly studied asselective extractants for separation of long-lived actinides fromirradiated nuclear fuel. In the last years, the research wasfocused on the derivatives of bis-triazinyl pyridine (BTP) whichselectively extract actinides(III) from lanthanides(III) fromaqueous HNO3 solutions to organic solvents. Moreover, selectivestripping of minor actinides can be done also, using a hydrophilicligand, e.g. SO3-Ph-BTP delivered by Technocomm Ltd (UK).

NN

NN N

NN SO3H

SO3HHO

3S

HO3S

HSO3PhBTP

| PAGE 4

Bibliography Complexes of An(III), Ln(III) with HSO3PhBTP

β Cm Euβ1 5,4 5,2

β2 9,3 8

β3 12,2 10,2

Stability constant of An with SO3‐Ph‐BTP ligand ←  TRLFS, An3+ forms more stable complexes than Ln3+.  Complexes (1:1), (1:2) and (1:3) were observed

Stability constants of Cm and Eu with SO3‐Ph‐BTP ligand; at pH 3 (TRLFS)

Ch.M. Ruff, U. Müllich, A. Geist, P. J. Panak, Dalton Trans., 2012, 41, 14594

Distribution ratio of Am (0.5 M NH4NO3 + HNO3 (pH 1)/ 0.2 M TODGA in kerosene A. Geist et al., Solv. Extr. Ion Exch.,30: 433–444, 2012

0.01

0.1

1

10

100

0 0.002 0.004 0.006 0.008 0.01

DA

m

HSO3PhBTP mol · L-1

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Liquid‐liquid Extraction of Actinides with TODGA

In certain separation schemes under study (innovative-SANEX)the f-block elements are extracted together from acidic PUREXraffinate to the organic phase using e.g. lipophlilic tri-O-dentateligand, TODGA.

TODGA-2

-1.5-1

-0.50

0.51

1.52

2.5

-1 -0.5 0 0.5 1log

D0

log [HNO3]

Th(IV)Pu(IV)UO2(VI)

0.2 M TODGA

Yuji Sasakia*, Yasuhiro Tsubataa, Yoshihiro Kitatsujia, Yumi, SolventExtraction and Ion Exchange Volume 31, Issue 4, 2013 401-415

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Principle of the LLE Method

n221

0 ......1 Lβ+Lβ+Lβ=DD

n

An4+ + sTODGA + uNO3- = [An(TODGA)s(NO3)u]4-u

An4+ + uNO3- = [An(NO3)u]4-u

An4+ + kBTP = [An(hsBTP)k]4-4k

hsBTP4- + aH+ = [hsBTP(H+)a]4-a

where hsBTP = SO3PhBTP

u3

su3s

NOTODGAAnNOTODGAAn )(Kex=

kBTPk

k

i

u3unitrate

u

i

0

hsBTPK+NOK+

D

1,

1][1

u

u

u3l

uNOAnAn

NOTODGAAn

1

43 ])([][

])([D0=

D=

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Method of the determination of the Distribution coefficient

| PAGE 7

0

500

1000

1500

2000

2500

0.4 2.4 4.4 6.4

c/s

MeV

02000400060008000100001200014000160001800020000

0 20 40 60 80 100c/s

keV

alpha spectrometry gamma spectrometry

spectrophotometry spectrophotometry

Complex Arsenazo(III)-Th 660 nm Complex Arsenazo(III)-UO2(2+) 655 nm

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Purification of ligand

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0.1

1

10

0 0.01 0.02 0.03

D

HSO3PhBTP mol ∙ L‐1

SO3H‐Ph‐BTP contaminated SO43‐

SO3‐Ph‐BTP purified

Ligand has to be additional purify in case of the presence sulphate which form relatively strong complexes with An(IV)

Test with BaCl2 can generate large amount of white powder

Neutralization wiht NaOH until pH = 7

Solubilization in MeOH at leastthree times

Evaporation or precipitation with acetone

Müllich, Udo, Geist, Andreas, Zevaco, Thomas EP 2 377 861 A1

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Preliminary experimentsExperiments with  Th(IV), Pu(IV)

UO22+ ,PuO2

2+, NpO22+ 

At pH 1 we observed the formation of the complex with Pu(VI) and reduction

0

0.1

0.2

0.3

0.4

800 820 840 860 880

Optical den

sity

nm

Pu(VI)

Pu(VI)LInstability of The complextime30 min 

0.001 M Pu(VI), HSO3PhBTP 0-0.15 M, pH 1

reduction

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-0,5

0

0,5

1

1,5

2

2,5

3

3,5

-5 -4 -3 -2 -1 0

log HSO3PhBTP

log

D0/

D-1

Am(III)Th(IV)U(VI)

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Extraction of An as a function of ligand

Extraction of Th(IV), Am(III) and UO22+ by TODGA in

5% octanol-keresone from acidic aqueous solution.Temperature of extraction 25 ºC , time 30 min, O/A =1

UO22+ Th Am

C Anmol/L 0.0002 0.0001 trace

C NO3- 1 1 1

Phaseaqueous 0.15 M 0.15 M 

HNO3

0.015 M HNO3

Phaseorganic

0.6 M TODGA

0.06 M TODGA

0.1 M TODGA

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Results ‐ Extraction of Americium from acidic solution HSO3PhBTP and NaNO3

-0.50

0.51

1.52

2.53

3.5

-5 -4 -3 -2 -1 0

log(

D0/

D-1

)

log (HSO3PhBTP)

0.5 M HNO3 0.15 M HNO30.01 M HNO3 0.5M HNO3 with Pu1 M HNO3 avec Pu

k=2

k=1

Phase organic: 0.1 M TODGA and 0.06 M TODGA when Am was measured with Pu

acidity log β1 log β2

0.02 5.27 ±0.54

8.24 ±1.01

0.15 4.76 ±0.45

8.73 ±1.03

0.5 4.70 ±0.51

8.48±1.04

1.0 5.21 ±1.01

9.74 ±2.01

3.0 In progress In progress

A. Geist, U. Mullich, G. Modolo, A. Wilden ACTINIDE AND FISSION PRODUCT PARTITIONING AND TRANSMUTATION, ISBN 978-92-64-99174-3, © OECD 2012 (1-9)

β Cm Euβ1 5,4 5,2β2 9,3 8β3 12,2 10,2

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Results ‐ Extraction of Plutoniumfrom acidic solution HSO3PhBTP and NaNO3

CPu(VI) = 0.1 mM, 1.0 M (H, Na)NO3TODGA = 0.06 M in kerosene/5% octanol

-1.5-1

-0.50

0.51

1.52

2.5

-4 -3 -2 -1 0

D0/

D-1

log(HSO3PhBTP)

0.5 M HNO3 France 1 M HNO3

k=2

k=1

acidity log β1 log β2

0.5 5.01 ±(0.51)

8.98 ±(1.01) 

1.0 4.34 ±(0.51)

8.80 ±(1.02)

3.0 In progress In progress

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Results ‐ Extraction of Uranium(VI) and Thorium(IV) from acidic solution HSO3PhBTP and NaNO3

log K1 = 2.660.15 M HNO3TODGA 0.6 M

tgα=1

preliminary results log K1 = 3.63 log K2 = 6,000.15 M HNO3TODGA 0.06 M

Th(IV)

00,20,40,60,8

11,21,41,61,8

-2,5 -2 -1,5 -1 -0,5 0

log HSO3PhBTP

log

D0/

D-1

Th(IV)

UO2(2+)

00,10,20,30,40,50,60,70,80,9

-2,5 -2 -1,5 -1 -0,5 0

log HSO3PhBTP

log

D0/

D-1

UO2(2+)

k=2k=1

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Conclusion

Am3+,Th4+, Pu4+ forms complexes 1:1, 1:2 and UO22+,

1:1 under the conditions of experiments. No evidence of the complexes 1:3 under the conditions of

experiments. The results for Am3+ are in accordance with the data

existed for Cm(III) and Eu(III). The order of the conditional stability constants for the

complexes 1:1 is Pu4+ ~ Am3+ > Th4+ > UO22+.

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ACKNOWLEDGEMENTS 

Prof J. Narbutt

M. RejnisK. Lyczko

Dr. Philippe MoisyDr. M. Ch. Charbonnel

L. BerthonC. BerthonN. BoubalsT. DumasD. GuillaumontP. GuilbaudC. TamainL. GuerinN. ZorzS. PetitR. BurgaudI. DantilleS. MostaphaO.PecheurM. AudrasM. Autillo

LN1 L18M. GuigueJ. VermeulenJ. Maurin

Prof. G. Zakrzewska KołtuniewiczA. MiśkiewiczM. ButaD. GajdaA. AbramowskaW. OlszewskaP. NieściórK. Kiegiel