Some recent applications of
extraction chromatography in
radioanalytical chemistry
S. Happel, TrisKem International, 20/03/13
Scope
• Rapid Sr-89/90 methods
– Sr-89/90 in sea water
• Y-90 in urine samples
– Sr-89/90 in milk powder
• Determination of Cl-36 (and I-129)
• Rapid method for the determination of Ra-228 in aqueous
samples
• Rapid method for the determination of Pb-210
Radiostrontium in sea water
Sherrod L. Maxwell, Brian K. Culligan & Robin C. Utsey: Rapid determination of radiostrontium in seawater
samples, J Radioanal Nucl Chem DOI 10.1007/s10967-013-2430-1
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Sea water: 7 – 8 mg Sr / L, 400 mg Ca / L
ICP-MS for yield
Preferably samples > 1L for low detection limits
Preconcentration by coprecipitation
2 options for separation:
– Sr-89/90: combined Sr/DGA resins
– Sr-90 only: DGA resin
• Measurement via GPC, LSC or Cerenkov
Maxwell et al. 2012
Maxwell
Maxwell
et al.
et al.
2012
2012
SRNL Sr-89/90 in sea water method
Analysed up to 6L sea water
• 1L sample: 4 mL SR resin
• 2L sample: 6 mL SR resin
• 6L: eluates from three 2L samples combined
 Sr yield 80% - > 90%; Y yield > 90%
 2L water, 1000 min count (GPC)
 MDA: 3 mBq/L
 By combining eluates of three 2L samples (“6L
sample”): MDA 1 mBq/L
 2L sea water sample
(one DGA cartridge)
 Chemical yields > 90%
Maxwell et al. 2012
Y-90 in urine samples
• On-going work, urine monitoring in nuclear medicine department
• Mineralisation followed by co-precipitation
• Separation on DGA
– Load from high HNO3, rinse with 8M HNO3, 0.1M HNO3 and 3M HCl, elution with 0.1M HCl
C. Dirks, 2012
Rapid method for the determination of Sr-89/90 in milk powder
Groska J, Molnar Z, Bokori E, Vajda N:
Simultaneous determination of 89Sr
and90Sr: comparison of methods and
calculation techniques, Journal of
Radioanalytical and Nuclear Chemistry,
March 2012, Volume 291 (3),707-715
Determination of Cl-36 / I-129 using CL resin
• CL resin originally planned for Pd separation
 Method testing still on-going
 Also showing high Ag uptake
• Halogen separation on Ag+ loaded CL resin
• Sample loading
A. Zulauf, S. Happel, M. B. Mokili, A.
Bombard, H.Jungclas: Characterization
of an extraction chromatographic resin
for the separation and determination of
36Cl and 129I. J. Radanal Nucl Chem,
286(2), 539-546
 Acidic, neutral or slightly alkaline conditions
 Might need to be done under reducing conditions
 Original paper: water/effluents and leached solid samples
 Especially in case of iodine: load from elevated sample volumes at elevated
flow rate
 Example: 3g CL resin (plus 4g XAD-4 resin), > 10 L radioactive process effluent
(1M HNO3), flow rate up to 180 mL/min, iodine uptake: 85 – 95%
 Iodine retention even in presence of very large excess of chloride (e.g. sea
water)
Determination of Cl-36 / I-129 using CL resin
• Rinse with 10ml of deion. Water
 Eliminates matrix elements
• Elute chloride with 5ml of 0.1M SCN-,
 Directly mixed with LSC cocktail and counted
• Rinse with 10ml of 1% NaOH
 Increases iodide yield
• Elute iodide with 5ml of 0.35M Na2S, mix with LSC cocktail
 Fume hood…
 Directly mixed with LSC cocktail and counted
• Yields in general > 90 - 95%
• Updated method uploaded in a few days
 Modified Ag loading of the CL resin column
• Larger solid samples?
Pyrolyser method
P E Warwick, A Zulauf, S Happel, I W Croudace: Determination of 36Cl in
decommissioning samples using a Pyrolyser furnace and extraction chromatographic
separations. Presentation at the 11th ERA Symposium, 16/09/2010, Chester (UK)
 Allows for analysis of large solid samples (several g)
 Thermal decomposition of the samples and desorption of
Cl Species in Pyrolyser furnace at 900°C (ca. 2h)
 System flushed with humidified air; samples also
humidified (1ml water)
 Decomposition products trapped in bubbler containing
alkaline solution
• 6 mM Na2CO3 used (yield > 80%)
Pyrolyser method
Bubbler connected directly with furnace via glass connector
• Avoid losses due to condensation in tubing
36Cl separated via Ag+ loaded Cl resin
• Separation similar to standard method, but bubbler solution loaded
directly onto column
• When loading column directly from 6 mM Na2CO3 additional rinsing
with 0.1M H2SO4 necessary for improved C-14 decontamination
(« modified wash »)
 Similar method currently tested for iodide
Pyrolyser method
• Decontamination factors Df:
 High Df
 Clean Cl-36 / I-129 separation
 Cl-36 separation yield > 95%
• Analysis of spent resin
 Good agreement
All Data from P. Warwick, GAU Radioanalytical, Southampton (UK)
Rapid determination of Ra-228 in water samples
Maxwell S.L. et al., Rapid method for determination of 228Ra in water samples,
J. Radioanal Nucl Chem, DOI 10.1007/s10967-012-2257-1 (2012)
• Rapid method (no wait for Ac-228 ingrowth after Ra-228 separaton)
• Routine: 1L samples
• Calcium carbonate precipitation
– Addition of phosphate for improved yield
• Cation exchange (5g column)
– Removes Ca, Pb, Bi, U, Th, Pa
• DGA Resin
– Ac purification (removes Pb, Bi, Sr, Y…)
• Yield via La (ICP-MS)
• Direct measurement (LSC or Cerenkov) or source preparation via
Ce/LaF3 precipitation (GPC)
• Separation in ~4h, Yield > 90%
50WX8
F- to complex Pa
Maxwell, 2012
Maxwell, 2012
Rapid method for the determination of Pb-210 in
water samples
 On-going work -> modified Sr resin (presentation J. Surman)
 Loading of pH neutral or acidified water sample onto column
• Concentration and separation on the same column
• Preferably at high flow rate
 First tests on modified SR resin
 Elution study, 1L water sample, pH 7
 1 mg Sr, 100 mg Ca, 5 mg K, 0.1 mg Pb, Y, U
 Column loaded in 100 mL aliquots, rinse with 15 mL 8M HNO3 (matrix
removal) and 20 mL 2M HCl (Sr elution)
 Load, rinse and elution at at 5 mL/min
 Effluents analysed by ICP-MS
Elution study mod. SR resin
 K and Ca break through during load
 Sr breakthrough starts at approx 600 mL
 Y eliminated with 8L HNO3, Sr eliminated with 2M HCl
 Pb quantitatively recovered in 20 mL 6M HCl, co-eluted with U….
 First test with ‘Disc’: 5L water sample, loaded in 1L aliquots, flow rate 30 mL/min:
• Pb breakthrough < 5-10% during load
• Aim: direct count of disc (similar to Tc-99 TEVA disc method) by LSC
Ionic liquids
 U selectivity introduced by HDEHP… improved selectivity by use of short
chained ionic liquids?
 Preliminary testing (elution study)
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Sample load from pH 7
Rinse with 3x5 mL 8M HNO3,
Sr elution mit 4x5 mL 2M HCl
Pb elution mit 4x5 mL 6M HCl
 Y and U removed with 8M
HNO3
 Sharp Sr elution
 Good purity of Pb fraction
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