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A Rapid Method for Analysis of Am, Pu, Th, U, Sr-90 in Urine and Fecal Samples Using Extraction Chromatography
Michael Schultz1, Barry Stewart2, Penet Melton3, Leisa Stegall3
1. PerkinElmer ORTEC, 801 S. Illinois Avenue, Oak Ridge, TN 37830, Phone: (865) 481-2446, Email: [email protected]
2. Carlsbad Environmental Monitoring and Research Center, 1400 University Drive, Carlsbad, NM, 88220, Phone: (505) 234-5543, Email: [email protected]
3. General Engineering Laboratories, Federal Division, 2040 Savage Road, Charleston, SC 29407, (843) 556-8171, [email protected].
Challenge
•To develop a dependable, rapid analytical procedure to analyze bioassay samples for Am, Pu, U, Th, and Sr-90.
Support D and D work
In some cases, data needed quickly.
Application
Urine Prep - CaC2O4
1-L tall formbeaker
•500 mL urine sample
•Acidify (HNO3) - Heat
•CaC2O4 precipitation (NaNO2, pH 2)
Am, Th, Pu (VI), and Sr*
•Let settle, centrifuge and decant
•Muffle 500 °C - Make CaCO3
•Dissolve (HNO3) - Sr(NO3) option
•Dry/Dissolve 3 M HNO3 - Load
*U remains in supernate.
Stacked Columns - Urine Pu on TEVA
•Precondition 10 mL 3 M HNO3
•Load 15 mL 3 M HNO3
FeSO4 (Pu3+), NaNO2 (Pu4+)•Rinse 4 mL 3 M HNO3
•Repeat rinse 4 mL 3 M HNO3
•Rinse 2 mL 3 M HNO3
Teva
Pu, Th
TRUAm
Sr, Ra?
Split columnsTevaPu, Th
TRUAm
Take load and rinse to dryness
Split Columns - Urine
•Rinse 5 mL (x3) 3 M HNO3 (residual U)•Eute Th
2 mL 9 M HCl5 mL 8 M HCl (x3)
•Elute Pu 20 mL 0.05 M HCl-0.05 M HF-0.02 MTiCl3
TRUAm
TevaPu, Th
•Rinse 5 mL (x3) 3 M HNO3- 0.05 M NaNO2 (Pu4+)•Eute Am
2 mL 9 M HCl15 mL 3 M HCl
TRU
Teva
TRU only - Urine
•Precondition 3 M HNO3
•Load 3 M HNO3
•Rinse 3 M HNO3, NaNO2 (Pu IV)
•Rinse 3 M HNO3
•Elute Am9 M HCl, 3 M HCl - TEVA (Am/La)
•Elute Th 4 M HCl - 0.1 M HF•Elute Pu 4 M HCl - 0.1 M Hydroquinone
Am, Th, Pu
TRU
Extra column may not be needed
Sample
Am and Pu Synthetic Urine
Sample ID (%) Am (%) Pu Sample ID (%) Am (%) Pu
1 95 92 6 98 1012 62 68 7 63 733 69 100 8 834 64 73 9 685 89 95 10 104 83
Average= 76 86 Average= 83 86St. Dev. = 15 14 St. Dev. = 18 14
TRU Only TEVA/TRU
Am and Th in Synthetic Urine
TEVA/TRUSample ID Am (%) Th (%)
1 99 862 98 853 98 83
Average = 98 83Std. Dev. = 1 2
Pu analyses failed - Ti oxide formationDo not take Pu fraction to dryness.
Recovery Real Urine TestsTRU-Only
Sample ID Am (%) Pu (%) Th (%)
1 94 53 852 97 66 763 93 65 80
Average = 95 61 80Std. Dev. = 2 7 5
Natural-blank urine samples - 3 subject donors
Fecal Prep - LaF3 Coprecip.
•Ash at 500 °C - slow ramp (1 day)
•Wet Ash HNO3/H2O2 - Repeat - white/lavender
•Convert to Cl- - dry - dissolve 2 M HCl
•HF - residue (remove Si)
•Combine - dry - dissolve - aliquot
•La3+, HF, NaNO2, heat, LaF3 - centrifuge
•Dissolve 3 M HNO3 - 2.5% H3BO3 - Ready
U (supernate) by anion exchange - AG1x8
TRU/AG 1x8/TEVA - Fecal
•Precondition 10 mL 3 M HNO3
•Load 15 mL 3 M HNO3
•Rinse 4 mL 3 M HNO3, repeat 2x•Elute Am
2 mL 9 M HCl20 mL 3 M HCl - TEVA (Am/La)
•Elute Pu (Th) 10 mL 0.1 M NH4HC2O4
•Dry, muffle, wet-ash dissolve•Pu AG 1x8 100-200 mesh Cl- form
Am, PuTRU
Extra column may not be needed
Sample
TEVA Am/La Separation - Fecal
•Dry Am fraction from TRU•Wet-ash with HNO3/H2O2
•Convert to HCOOH form•Dissolve in 10 mL 3 M NH4SCN - 0.1 M HCOOH•Load
Rinse 2x 1.3 M NH4SCN - 0.1 M HCOOH•Elute 10 mL 2 M HCl•Ready for source prep.
Am, LaTEVA
Replace HCOOH with HCl?
TEVA Am/La Separation - HCl
•pKa HCOOH 1.9E-4, pH ~2.5•Replace HCOOH with HCl•Same procedure•Load Solution 3 M NH4SCN - 0.005 M HCl•Elute 2 M HCl•Ready for source prep.
Am, LaTEVA
Replace HCOOH with HCl?
Experiment (n=3)
Am/La (NH4SCN/HCl)
TEVA (HCl)Sample ID Am-243 Yield Am-241 Recovery
(%) (%)1 70 1052 88 1123 87 96
Average = 82 104Std. Dev. = 10 8
Column Tests - Good Resolution
Results Summary - Urine Am yield 90+% (TEVA/TRU or TRU)
real and synthetic urine
Pu yields are variable 50% to 100% for TEVA/TRU or TRU only
Sr, Ra, and U yet to be evaluated Source prep is possible within 24 hours
with two shifts.
Results Summary (n~100’s) - Fecal Am Yield 78%
real fecal samples
Pu Yield 80% real fecal samples
Good U/Th yields (data not shown) Analysis in 72 hours (two shifts). Am/La separation on TEVA promising
Future Work Am/Rare Earth Separation
TEVA/HCl
Pu Eliminate AG1 (TRU or TEVA)
Add U Add Sr
Nitrate before TRU/TEVA
Collaborators welcome!
