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Challenge

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Challenge

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  1. A Rapid Method for Analysis of Am, Pu, Th, U, Sr-90 in Urine and Fecal Samples Using Extraction ChromatographyMichael Schultz1, Barry Stewart2, Penet Melton3, Leisa Stegall31. PerkinElmer ORTEC, 801 S. Illinois Avenue, Oak Ridge, TN 37830, Phone: (865) 481-2446, Email: michael.schultz@perkinelmer.com2. Carlsbad Environmental Monitoring and Research Center, 1400 University Drive, Carlsbad, NM, 88220, Phone: (505) 234-5543, Email: bstewart@cemrc.org 3. General Engineering Laboratories, Federal Division, 2040 Savage Road, Charleston, SC 29407, (843) 556-8171, pem@gel.com.

  2. Challenge • To develop a dependable, rapid analytical procedure to analyze bioassay samples for Am, Pu, U, Th, and Sr-90.

  3. Application Support D and D work In some cases, data needed quickly.

  4. Urine Prep - CaC2O4 • 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 1-L tall form beaker *U remains in supernate.

  5. TRU Am 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 TRU Teva Am Split columns Pu, Th Sr, Ra? Take load and rinse to dryness

  6. Split Columns - Urine Teva Teva • Rinse 5 mL (x3) 3 M HNO3 (residual U) • Eute Th • 2 mL 9 M HCl • 5 mL 8 M HCl (x3) • Elute Pu 20 mL 0.05 M HCl-0.05 M HF-0.02 MTiCl3 Pu, Th TRU TRU • Rinse 5 mL (x3) 3 M HNO3- 0.05 M NaNO2 (Pu4+) • Eute Am • 2 mL 9 M HCl • 15 mL 3 M HCl Am

  7. TRU only - Urine • Precondition 3 M HNO3 • Load 3 M HNO3 • Rinse 3 M HNO3, NaNO2 (Pu IV) • Rinse 3 M HNO3 • Elute Am • 9 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 TRU Sample Am, Th, Pu Extra column may not be needed

  8. Am and Pu Synthetic Urine

  9. Am and Th in Synthetic Urine Pu analyses failed - Ti oxide formation Do not take Pu fraction to dryness.

  10. Recovery Real Urine Tests Natural-blank urine samples - 3 subject donors

  11. 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

  12. 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 HCl • 20 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 TRU Am, Pu Sample Extra column may not be needed

  13. 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. TEVA Am, La Replace HCOOH with HCl?

  14. TEVA Am/La Separation - HCl Experiment (n=3) TEVA Am, La • 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. Replace HCOOH with HCl?

  15. Am/La (NH4SCN/HCl) Column Tests - Good Resolution

  16. 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.

  17. 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

  18. Future Work • Am/Rare Earth Separation • TEVA/HCl • Pu • Eliminate AG1 (TRU or TEVA) • Add U • Add Sr • Nitrate before TRU/TEVA Collaborators welcome!

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