CTU Prague
Task T3.1.3
Materials and processes for residual
actinides separation
J. John, K.V. Mareš, F. Klímek,
F. Šebesta
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
Introduction
Aim:
Contribute to the optimisation of separation technology at the pilot scale,
namely to:
• Minimisation of waste production
• Minimisation of additional waste management costs.
Proposal:
Screen existing or optimise the promising, and/or develop, if necessary,
novel chromatographic materials for “polishing” of the future secondary
waste streams aiming at down-classification or even free release.
Expected results:
Novel materials and procedures for the polishing of the secondary waste
streams
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
Approach
Two options:
1) Repeated use:
• Load – elute (– regenerate) cycle
• Critical issues:
• Stability of the active component (radiation, chemical)
• Resistance against release of the active component
• Less critical issues:
• Uptake capacity
• Price
2) Once-through:
• Load – dispose-off regime
• Critical and less-critical issues exactly reversed
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
Target stream
PUREX raffinate without MA as the secondary waste (as per definition
supplied by WP Leader on the 4th November 2009).
Elements
Se
Rb
Sr
Y
Zr
Mo
Tc
Ru
Rh
Pd
Ag
Cd
Sn
Sb
Te
PUREX raffinate (mg/L)
15
85
200
110
900
855
5
290
60
375
20
25
15
5
125
[HNO3] (mol/L)
Elements
Cs
Ba
La
Ce
Pr
Nd
Pm
Sm
Eu
Gd
U
Np
Pu
Am
Cm
3
PUREX raffinate (mg/L)
915
430
305
600
280
1 025
10
200
40
30
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
Studies – Year 1 (ACSEPT Year 2)
Regenerable materials
TODGA–PAN
• General study of re-usability including
• Large volume treatment
• Uptake capacity
• Elution efficiency
• Resistance against release of the active component
BTBP-based materials
• Optimisation of the materials (batch experiments)
• Chromatographic application – separation of pre-concentrated An from Ln
• „Sorption filter“ application – selective uptake of MAn from a model stream
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
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Dynamic studies
BV = 1.27 ml
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
TODGA–PAN studies (1)
Large volume processing
Verification of the behaviour of a TODGA–PAN column bed during the
treatment of a large volume of model solution
• 5.10–5M Eu(NO3)3 in 3M HNO3 passed through a 1.27 mL column of
TODGA–PAN at 3 BV/hr (3.8 mL/hr).
• Run till the saturation (100% break-through).
• Total volume of the feed processed – 340 BV (430 ml)
• Duration of the sorption – 115 hours.
Results
• 50% break-through after processing of 240 BV of the solution.
• Symmetric break-through curve.
• Practical sorption capacity (0.17 mmol/g) close to the theoretical capacity
 no significant washing of TODGA from the SEX occurs.
• Quantitative elution of Eu achieved in 12 BV of 0.5M solution of
glycolic acid with pH ~ 4.
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
TODGA–PAN studies (2)
Break-through curve of 5.10–5M Eu(NO3)3 in
3M HNO3 through a 1.27 mL column of
TODGA–PAN at 3 BV/hr (3.8 mL/hr)
Elution of Eu with 0.5M solution of
glycolic acid with pH ~ 4 from a 1.27 mL
column of TODGA–PAN fully loaded with Eu
(flow rate 3 BV/hr / 3.8 mL/hr)
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
TODGA–PAN studies (3)
Load – elute cycling
Influence of Eu elution on the sorption properties of the TODGA–PAN?
Existence of washing of TODGA from SEX?
• Sorption cycles – 5.10–4 mol/l Eu(NO3)3 in 3M HNO3, full loading.
• Elution cycles – 25 BV of the eluant used per cycle.
• Five sorption / elution cycles performed.
Results
• Capacity decreased by ~ 10 % between the first and the third sorption
cycle and then remained practically constant.
• Elution of europium remained quantitative throughout the five cycles.
Interpretation
• TODGA extractant attached to the outer walls of the beads is washed out
during the first and the second sorption cycle
• The extractant incorporated inside the pores is strongly bound to
the beads and cannot be easily washed.
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
TODGA–PAN studies (4)
Cycle No.
1
2
3
4
5
Qm [mmol/g]
0.180
0.170
0.163
0.161
0.160
Practical sorption capacities
Qm of a TODGA–PAN solid
extractant measured in
successive sorption / elution
cycles (3M HNO3, 5.10–4M
Eu3+, BV=1.27 ml, v = 3 BV/hr)
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
PAN-BTBP based materials (1)
Background (EUROPART)
1,E+4
150
Am
Eu
90
1,E+2
60
1,E+1
30
ob
e
nz
en
e
♣ the behaviour of our
SEXs similar to that in
LLX
ni
tr
he
x
cl
o
cy
♣ the most promising
SEXs with
nitrobenzene and
tetrachloroethane
te
tra
ch
lo
ro
et
ha
n
an
on
e
e
ha
n
lo
ro
et
di
ch
oc
ta
e
0
no
l
1,E+0
SF(Am/Eu)
120
1,E+3
Dg / mL.g-1
Conclusions
SF
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
PAN-BTBP based materials (2)
SEX:
Am – HNO3
Eu – HNO3
Am – HGlyc
Eu – HGlyc
E5–C5BTBP[nitrobenzene]
BT (%)
BT (%)
(oversaturated C5BTBP in
nitrobenzene on Synachrom E5)
Batch experiments:
Dg(Am) ~ 3000 mL/g,
SFAm/Ee ~ 100
Sorption:
carrier free Eu3+ + Am3+
in 1M HNO3
Results
Europium fraction: > 98.6 % Eu in 9 BV, 0.3 % of Am
Americium fraction: 99.7 % Am in 2.5 BV,
contaminated by 1.4 % of Eu
Eu elution:
1M HNO3, v = 0.12 BV/hr
Am elution:
0.5M HGlyc, pH = 4,
v = 0.13 BV/hr
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
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PAN-BTBP based materials (3)
E5-CyMe4BTBP[cyclohexanone]
(saturated CyMe4BTBP in cyclohexanone on Synachrom E5)
1) Dgs
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
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PAN-BTBP based materials (4)
E5-CyMe4BTBP[cyclohexanone]
2) Kinetics
Acceleration of the kinetics in cyclohexanone ascribed to
the “phase-transfer” effect of cyclohexanone
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
PAN-BTBP based materials (5)
E5-CyMe4BTBP[cyclohexanone]
BTAm [%]
3) Maximum flow-rate determination (1M HNO3, carrier free Am + Eu)
35
Conclusions:
30
• Up to 5 BV/hr a constant
1–2 % break-through of
Am observed
• Sharp increase of breakthrough above 10 BV/hr.
was observed
25
20
15
10
 Allows for practically
applicable flow-rates
5
0
0,1
1
10
100
v [BV/hr]
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
PAN-BTBP based materials (6)
E5-CyMe4BTBP[cyclohexanone]
3) „Sorption filter“ application – selective uptake of MAn
20.4
BV/hr
1000
Breakthrough [%]
Feed (Am +Eu in 1M HNO 3
60
1M 0.5M
HNO3 HGlyc
50
100
Elution [%]
10.8
BV/hr
40
0.26
BV/hr
0.18
BV/hr
10
0.56
BV/hr
2.32
BV/hr
4.83
BV/hr
30
20
1
Am
Eu
Am - elution
Eu - elution
0,1
0
10
20
10
0
30
40
50
60
70
V [BV]
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
Feed:
carrier free Eu + Am in
1M HNO3, Volume = 65 BV
Wash:
1M HNO3
Am elution:
0.5M HGlyc, pH = 4
Results:
Am recovery >98%, <1%
of Eu in Am fraction
Eu recovery >99%, <2%
of Am in Eu fraction
CTU Prague
Future Plans (Year 2)
Regenerable materials:
• Continue with E5-CyMe4BTBP[cyclohexanone]
• solutions with realistic Ln concentrations
• full simulants
Once-through materials:
Try to develop a BTP-based material from the BTP with the highest
available Am-extraction efficiency.
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal
CTU Prague
Thank you for your attention
ACSEPT Second Annual Meeting,
29-31 March, 2010 - Lisbon, Portugal