Rapid Emergency Methods for Actinides and Sr-89/90 Sherrod L. Maxwell, III Westinghouse Savannah River Company
Jan 12, 2016
Rapid Emergency Methods for Actinides and Sr-89/90
Sherrod L. Maxwell, III
Westinghouse Savannah River Company
Background
• Radiological Preparedness Exercise (NRIP’04)– Kenneth Inn, NIST
– spoke at RRMC-2004 of “need to improve efficiency and effectiveness of radioanalytical capabilities”
• Need for faster actinide and Sr-89/90 analyses for Homeland Security reasons
• Current water/air filter methods may take 1-2 days • Need for fast, reliable methods (< 8 hours)
Developments at SRS
• Water/Air Filters Method– Streamline calcium phosphate precipitation
(water)– Dissolve air filters– Collect and prepare Sr-89/90 with actinides– No ashing of Am/Cm or Th fractions
• Eichrom prefilter cartridges/Resolve filters
Developments at SRS• Streamline calcium phosphate precipitation
– Eliminate heat step for volumes less than 200 mL/add Ba to complex carbonate
– Use 200 mL (or less) sample volumes in centrifuge tubes– Prep time: ~1-1.5 hours-12 samples
• Stack TEVA (Pu, Np, Th) + TRU (Am,Cm, U) + Sr Resin (Sr-89/90)– Collect Sr-89/90 at same time– Prep time: <4 hours-12 samples
• Count time– actinides-1 hour (or as needed)– Sr-89/90-10 minutes (or as needed)
Rapid TEVA-TRU-Sr Separations(Pu, Np, Am, Cm, U, Sr)
Remove Sr on Sr Resin, Pu from TEVA and Am-Cm/U from TRU
Am Strip with Prefilters Below TRU
Performance
• 20 groundwater samples • 200 mL volume/ 6 hour counts *• Sr carrier recoveries: 98.1% (3.9% rsd)• Pu-242 recoveries: 104% (4.9% rsd)• Am-243 recoveries: 92.6% (6% rsd)• U-232 recoveries: 85.6% (5.4% rsd)
*count less time in emergency when high levels expected
Other Efficiency Improvements
• Eliminate ashing steps used for extractant bleed-off that affects alpha resolution
• Prefilter cartridge(~$5) with Resolve filters– Saves time, labor, better FWHM– faster TAT– improved alpha resolution– less rework
Resolution with Filters from “Bad” Lot
Summary
• Need to share radioanalytical methods-Ken Inn• Faster actinide and Sr-89/90 methods developed
– Quality and Speed– Streamlined precipitation for water samples– Collect Pu, Am, Cm, U, Sr in a single stacked column– High recoveries, good resolution, no interferences
• Applicable to radiological emergency analyses– Improved efficiency and effectiveness– Short count as needed– Analysis time < 8 hours