Actinide chelation on the surface of silica gel and in aqueous … · 2012-03-26 · Actinide...
Transcript of Actinide chelation on the surface of silica gel and in aqueous … · 2012-03-26 · Actinide...
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
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)