Actinide chelation on the surface of silica gel and in aqueous … · 2012-03-26 · Actinide chelation on the surface of silica gel and in aqueous solution German-French research

Actinide chelation on the surface of silica gel and

in aqueous solution

German-French research for nuclear safety: Chemistry of the f-elements

22–23 February 2012

Michel MEYER

Institut de Chimie Moléculaire de l’Université de Bourgogne ICMUB – UMR 6302 du CNRS

[email protected]

Flow Sheet of the Nuclear Wastewater Treatment!

Radioactive mud conditioning (concrete matrix 15 m3/year)

Long-term storage

CEA Valduc

Removal of U, Pu, and Am α-emitters

•  Microfiltration 0.2 µm •  Efficient uptake of U and Pu (colloïdes) •  Inefficient for Am3+

> 18.5 MBq/m3 < 18.5 MBq/m3

Distillation

< 400 Bq/m3 < 5 Bq/m3

Micro-filtration

Atmosphere 550 m3/year

> 5 Bq/m3

Filtration

Semi-industrial Decontamination Plant

Element U Am U, Pu, Am α Activity (Bq/m3) 180 16 887 Concentration (7 mg/L) (126 pg/L) Treated volume (m3) 16 18 12 Residual α activity < DL (5 Bq/m3)

OOOH

SiOEt

(CH2)3

NH+

N

N

+HNCOO-

COO--OOC

R. Guilard, H. Chollet, P. Guiberteau, P. Cocolios PCT Application WO 96 11056, 1996 H. Chollet, J.-L. Babouhot, F. Barbette, R. Guilard PCT Application WO 01 15806, 2001 F. Barbette, F. Rascalou, H. Chollet, J. L. Babouhot, F. Denat, R. Guilard Anal. Chim. Acta 2004, 502, 179

Structural Studies of Isolated and Surface Complexes

EXAFS characterization at the LIII-edge of UO22+ and Pu4+ complexes

In collaboration with C. Hennig and A. Scheinost, ESRF ROBL BM20 beamline (Grenoble)

N

N

N

N CO2–

CO2––O2C N

N

N

NCO2–

CO2––O2C

TE3Pr3– TE3Ac3–

OOOH

SiOH

(CH2)3

N

N

N

N CO2–

CO2––O2C

OHOHOH

Kieselgel SiTE3Pr SiTE3Ac

OOOH

SiOH

(CH2)3

N

N

N

NCO2–

CO2––O2C

+ UO22+

pH ~2 N

N

N

N CO2–

CO2––O2C

–O2C

Crystallographic characterization

[UO2(H6TETPr)(H2O)2](NO3)4

U(VI) Complexes: LIII-Edge EXAFS Spectra

U–OSi = 2.30 Å U–OW = 2.49 Å U–Si = 3.14 Å (lit. 2.9–3.2 Å)

U–OSi = 2.29 Å 2.28 Å U–OW = 2.49 Å 2.50 Å U–OC = 2.50 Å 2.50 Å (lit. ~2.4 Å) U–Si = 3.20 Å 3.11 Å

U–OW = 2.44 Å U–OC = 2.50 Å U–Cbid = 2.88 Å

L. Giachini, S. Faure, M. Meyer, L. V. Nguyen, B. Batifol, H. Chollet, R. Guilard, A. C. Scheinost, C. Hennig, Speciation, techniques and facilities for radioactive materials at synchrotron light sources, Actinide XAS 2008, Proceedings of the 5th Workshop, NEA/NSC/DOC(2009)15, OECD Nuclear Energy Agency, 2009, 27

0 2 4 6-­‐9

-­‐6

-­‐3

0

3

6

9

T E 3P r

S iT E 3P r

K ies e lge l

Amplitu

de  FT

R  +  Δ  (Å )

U–Si

U=Oax 1.79 Å

U–Oeq U–O–C

O=U=Oax U–Cbid

Pu(IV) Complexes: LIII-Edge EXAFS Spectra

Pu–O (CN = 9)

2.18–2.39 Å

Pu–Pu (CN = 3–4)

3.78 Å

Pu–C (CN = 4) 3.41 Å

Formation of PuO2-type clusters

interacting with • carboxylates Pu–C = 3.40 Å • silanolates Pu–Si = 3.1 Å (?)

cfc–PuO2

Pu···Pu = 3.816 Å (CN = 4)

Pu···Pu = 5.396 Å

(CN = 1)

Learn much more in Christoph Hennig’s talk

R + Δ (Å)

Thermodynamic Studies of Pu(IV) / Complexones

Linear polyaminocarboxylates

•  Extracting agents

•  EDTA: ~80 t in the Hanford waste tanks (USA)

•  Na3[Zn(DTPA)]: FDA-approved in vivo decorporating agent of Pu

•  No reliable thermodynamic data available for Pu(IV) in 2005 according to NEA-TDB (Thermochemical Data Base) and IUPAC

W. Hummel et al. Chemical Thermodynamics of Compounds and Complexes of U, Np, Pu, Am, Tc, Se, Ni, Zr with Selected Organics Ligands, Chemical Thermodynamics Series Vol. 9, Elsevier, Amsterdam, 2005

G. Anderegg et al. Pure Appl. Chem. 2005, 77, 1445

DTPA5–

N

N–O2C

–O2C

N

CO2–

CO2–

–O2CN N

–O2C CO2–

–O2C CO2–N

N

CO2–

CO2––O2C

–O2C

EDTA4– CDTA4–

Pu(IV) / EDTA: Speciation at I = 1 M KNO3

Pu(EDTA) log K110 25.8(1) UV-vis [Pu(EDTA)(OH)]– log K11–1 3.9(1)

[Pu(EDTA)2]4– log K120 9.9(1) Potentiometry [Pu(EDTA)2H]3– log K121 7.0(4) Global analysis

[Pu(EDTA)2H2]2– log K122 2.7(4) (9 titrations)

Pu(OH)4(am) precipitates at p[H] ~ 3.5

0 2 4 6 8 100

20

40

60

80

100

%  P

u

p[H ]

P u(L )

P u(NO3)2+2

[P u(L )2H ]3-­‐[P u(L )(O H )]-­‐

[P u(L )2]4-­‐

P u(O H )4(am )

[Pu]T = [L]T = 2.5 mM

Pu(OH)4(am) precipitates at p[H] ~ 6.5

0 2 4 6 8 100

20

40

60

80

100

[P u(L )2H

2]2-­‐

[P u(L )2H ]3-­‐

[P u(L )(O H )]-­‐

[P u(L )2]4-­‐

P u(O H )4(am )

%  P

up[H ]

P u(L )

[Pu]T = 2.5 mM, [L]T = 5 mM I = 1 M (H,K)NO3, T = 298 K

M. Meyer, R. Burgat, S. Faure, B. Batifol, J.-C. Hubinois, H. Chollet, R. Guilard C. R. Chimie 2007, 10, 929

Pu(IV) / EDTA: Spectrophotometric Studies at I = 1 M KNO3

400 500 600 700 800 9000.0

0.1

0.2

0.3

10

1

A

λ (nm)

1.55 ≤ p[H] ≤ 2.39 T = 296 K

400 500 600 700 800 9000.0

0.1

0.2

0.3

13

1A

λ (nm)430 500 570 640 710 780 8500

25

50

75

100 Pu(L) [Pu(L)2H]3–

[Pu(L)2H2]2–

ε

(M–1

cm

–1)

λ (nm)

1.70 ≤ p[H] ≤ 6.63 T = 296 K

[Pu]T = [L]T = 4.67 mM

[Pu]T = 3.08 mM, [L]T = 6.17 mM

Calculated spectra

430 500 570 640 710 780 8500

25

50

75 Pu(IV) Pu(L) [Pu(L)(OH)]–

ε (M

–1 c

m–1

)

λ (nm)

log K121 = 7.1(1) log K122 = 2.7(1)

log K11–1 = 4.0(1)

Pu(IV) / EDTA: Electrophoretic Studies at I = 1 M KNO3

0 200 400 600 8000

2000

4000

6000

[P u(E DTA)OH]–

75.5%

Intens

ity  (c

ount  ra

te)

T ime  (s )

neutral

P u(E DTA)24.5%

µ = –1.04 x 10–4 cm2 V–1 s–1

I = 1 M KNO3, T = 298 K, pH = 5.0, [MES] = 50 mM, surfactant: [TTAB] = 0.2 mM tinj = 5 s, ΔPinj = 0.5 psi, ΔV = 10 kV, capillary: 60 cm × 50 µm

[Pu]T = [EDTA]T = 10–7 M at p[H] = 5.0

10-7 10-6 10-50

20

40

60

80

100

[Pu(EDTA)2H]3–

Pu(EDTA)

[Pu(EDTA)OH]–

% P

u

[EDTA]tot (M)

[Pu(EDTA)OH]– Pu(EDTA) Expected 78% 17% EC-ICPMS 75% 25%

In collaboration with J. Aupiais and S. Topin (CEA-DAM/DASE/SRCE, Bruyères-le-Châtel)

Pu(IV) / EDTA: EXAFS Data Processing

Pu–O = 2.34 Å (CN = 7 ± 1)

Pu–N = 2.62 Å (CN = 2 ± 1)

Pu–C = 3.34 Å (CN = 10 ± 1)

Pu–O = 4.59 Å (CN = 4 ± 1)

Nonacoordinated Pu (7O + 2N)

⇒ Pu(EDTA)(H2O)3

0 1 2 3 4 50

1

2

3

4

5FT

Am

plitu

de [k

3 χ(k

)]

R (Å)Yu. N Mikhailov et al. Koord. Khim. 1985, 11, 545

Crystal structure of [An(EDTA)F3]3–

An = Th4+ and U4+ Pu–O Pu–N

Pu–O

Pu–C

0.94 0.98 1.02 1.06 1.102.2

2.6

3.0

3.44.44.64.8

ThUPu

X = O(CO)

X = C

X = N

X = OAn

–X (Å

)

ri (Å)

Actinides and Hydroxamic Siderochelates

•  ~109 microorganisms in 1 g of soil: 103–104 different species

•  Concentration of hydroxamic siderophores in soils: 0.01–0.1 µM (2–250 µg/kg)

•  High affinity for hard cations: z/r = 4.6 Fe3+ vs. 4.3 e–/Å Pu4+

•  Dissolution of actinide hydroxides: log Ks = –38 Fe(OH)3 vs. –55 Pu(OH)4

Management of contaminated and nuclear waste storage sites Source of inspiration for the organic chemist

Bioavailability and mobility increase in contaminated environment

NHO

NO

OH

O

NO

HO

HN

O

=

Desferrioxamine B (DFB)

N(CH2)2

O

(CH2)5N

HO

(CH2)2

O

NO

(CH2)5N

HO

CH3

ON

HO

(CH2)5

O

+H3NHH

Siderophore-Mediated Actinide Uptake into Bacteria

[PuIV(DFE)(H2O)3]+ Desferrioxamine E (DFE)

HN

N

HN

N

ONH

NOHO

O

HO

O

O

OH

O

Pu(III), Pu(IV), Pu(V), Pu(VI) Pu(OH)4, PuO2

log K110 ~ 31

C. E. Ruggiero, M. P. Neu, J. H. Matonic, B. L. Scott, Angew. Chem. Int. Ed. 2000, 39, 1442

Active transport of Fe(III) and Pu(IV) through bacterial membranes (e.g. Microbacterium flavescens) But DFB doesn't promote UO2

2+ uptake!

S. G. John, C. E. Ruggiero, L. E. Hersman, C. S. Tung, M. P. Neu, Environ. Sci. Technol. 2001, 35, 2942

UO22+ / Desferrioxamine B: Speciation at I = 0.1 M KNO3

I = 0.1 M KNO3, T = 298 K

log K011 = 11.06(3) log K012 = 9.69(2)

log K013 = 8.95(3)

log K014 = 8.36(3)

N(CH2)2

O

(CH2)5N

–O

(CH2)2

O

NO

(CH2)5N

–O

CH3

ON

–O

(CH2)5

O

H2NHH

Desferrioxamine B

UO22+ + LH2– D [UO2(DFB)H] log K'111 = 16.4(1)

[UO2(DFB)H] + H+ D [UO2(DFB)H2]+ log K'112 = 6.3(1)

[UO2(DFB)H2]+ + H+ D [UO2(DFB)H3]2+ log K'113 = 3.7(1)

320 420 520 6200.0

0.3

0.6

0.9

1.2

A

λ (nm)

p[H] = 2.31

p[H] = 9.38

320 420 520 6200

400

800

1200

1600 [UO2(LH)] (λmax = 365 nm) [UO2(LH2)]

+ (λmax = 376 nm) [UO2(LH3)]

2+ (λmax = 388 nm) UO2

2+ (ε x 20)

ε (M

–1 c

m–1

)

λ (nm)

UO22+ / Desferrioxamine B: Binding Scheme

O

OOH2

O

ON

N

O

OHN

NH3+

U

log K'113

3.7(1)

+ H+

OHO

NNH3+

OHO

N

OO

H2O

H2OOH2

N

U

0 1 2 3 40

2

4

6

8

10

FT  M

odulus

R  +  Δ  (Å )0 1 2 3 4

0

2

4

6

8

10

FT  M

odulus

R  +  Δ  (Å )

EXAFS U–Oeq = 2.39(1) Å (CN = 5 ± 1) U–OC = 2.40(5) Å

U–ON = 2.41(8) Å

p[H] = 2.4 p[H] = 4.6

[UO2(DFB)H2]+ [UO2(DFB)H3]2+

ε388 = 475 M–1 cm–1 ε376 = 700 M–1 cm–1

UO22+ / Desferrioxamine B: Binding Scheme

O

OOH2

O

ON

N

O

OHN

NH3+

U

log K'112

6.1(1)

+ H+

log K'113

3.7(1)

+ H+

OHO

NNH3+

OHO

N

OO

H2O

H2OOH2

N

U

[UO2(DFB)H2]+ [UO2(DFB)H3]2+

[UO2OH(DFB)H2] [UO2(DFB)H] ≡

log K = 5.5 UO2(OH)+

O

O

O O

O

ON

N

N NH3+

U

O

O O

ON

N

ON

NH3+

U

O

O

OOH2

O

ON

N

O

O–N

NH3+

U

O

OOH

O

ON

N

O

OHN

NH3+

U

UO22+

+ (DFB)H2–

log K'111

16.44(1)

ε388 = 475 M–1 cm–1 ε376 = 700 M–1 cm–1

ε365 = 1450 M–1 cm–1

p[H] 6.50

4.56

3.76

1.98

Raman shift (cm–1) 800 900

UO22+ / LPr: Raman Spectroscopy as a Speciation Tool

1.98 6.50 4.56 3.76

2 4 6 80

20

40

60

80

100[UO

2(L )O H ]–

[UO2(L )H ]+

[UO2(L )]

%  U

O2

pH

UO2

2+

νsym O=U=O

834 cm–1 ~810 cm–1

850 cm–1

873 cm–1

UO2(H2O)52+

(LPr)H2

[U(VI)]T = [LPr]T = 5 10–3 M

UO22+ / Desferrioxamine B: Dissociation Kinetics

)( ∞

−−++= AtkatkatA

sobs

2

fobs

1 e e

0 100 200 3000.00

0.02

0.04

0.06

A

Time (ms)

[UO2(DFB)H2+]0 = 0.25 mM, pH = 5.4

[HNO3]0 = 2.5 mM

I = 0.1 M KNO3, T = 298 K

Stopped-flow spectrophotometer Kinetic trace at λ = 350 nm

[UO2(DFB)H2]+ + 2 H+ UO22+ + (DFB)H4

+

Pseudo-first order conditions: bi-exponential decay

⇒ 2 Consecutive rate-limiting dissociation steps

UO22+ / Desferrioxamine B: Dissociation Mechanism

O

OOH2

O

ON

N

O

OHN

NH3+

U

OHO

NNH3+

OHO

N

OO

H2O

H2OOH2

N

Uk1 = 88(2) x 103 M–1 s–1

+ H+

UO22+ + (DFB)H4

+

+ H+

320 420 520 6200.00

0.02

0.04

0.06

0.08

A

λ (nm)

Diode-array monitoring

[UO2(DFB)H2]+ [UO2(DFB)H3]2+

λmax = 376 nm λmax = 388 nm

Δt = 4 ms

k–2 = 5.7(6) s–1 k2 = 4.5(2) x 103 M–1 s–1

Acknowledgements

Action Concertée Incitative "Jeunes Chercheurs" 2004–2007 ANR – Projet "Chélan" 2006–2010

European Network of Excellence ACTINET Groupement National de Recherche PARIS 2009–2010

European Synchrotron Radiation Facility (ESRF)

Novartis (gift of DFB) and Chematech SAS

Centre National de la Recherche Scientifique (CNRS) Commissariat à l'Energie Atomique (CEA)

Conseil Régional de Bourgogne Ministère de l’Enseignement Supérieur et de la Recherche

Dr R. BURGAT (PhD) Dr L. V. NGUYEN (PhD) Dr L. GIACHINI (post-doc) Dr S. AMARASINGHE (post-doc) M. BOURDILLON (IE - ANR) R. OLANDA (Master)

Dr C. HENNIG (ESRF) Dr A. SCHEINOST (ESRF)

Dr S. BRANDES (ICMUB) Dr H. CHOLLET (CEA) Dr B. BATIFOL (CEA) Dr S. FAURE (CEA) Dr J. AUPIAIS (CEA)