Fenton s Reagent Digestion of Urine for Polonium Analysis

Transcription

1 Fenton s Reagent Digestion of Urine for lonium Analysis Daniel McAlister, Ph.D. Eichrom Technologies, LLC Sherrod Maxwell Savannah River Nuclear Solutions

2 lonium Element from U 238/Ra 226 Decay Relatively volatile (Cl 4 sublimes at 200 o C) 208 t 1/2 = yrs MeV 210 t 1/2 = 130 dys MeV 209 t 1/2 = 103 yrs MeV Biological Studies with lonium, Radium and Plutonium, R. M. Fink, McGraw Hill Book Company, New York, 1950

3 Early Analysis Methods Lacassagne studied biological distribution of 210 in rabbits ( ) Urine boiled with HCl, and deposited onto silver foil. Tissues digested with KClO3 and HCl, and deposited onto silver foil. Only 12% activity balance in excrement and tissues. Initially concluded that significant losses must occur through respiration of volatile species. Later studies showed that low activity balance due to incomplete recovery of. Digestion procedures inadequate. Better recoveries from urine/tissue digested with HNO3/HClO4 in Kjeldahl flask. Only six of 5000 samples caught fire Biological Studies with lonium, Radium and Plutonium, R. M. Fink, McGraw Hill Book Company, New York, A. Lacassagne, J. Lattes, J. Lavedan, J. Radiol. Electrol, 9:1, 67 (1925).

4 Challenging Matrix 1) Volume: ml/24 hrs. Average: 1,200 ml. 2) Specific gravity: ) (ph: ) Average ph: 6.0 4) Total solids: g/liter. Na + (3 6g) K + (1 3g) Ca 2+ ( g) PO 4 3 (1 2g) SO 4 2 (1 4g) Mg (40 200mg) NH 4+ (0.3 1g) I (50 250mg) Cl (9 16g) N N N Purine Bases (7 10mg) Oxalic acid (15 20mg) Hippuric acid (0.1 1g) Urea (25 30g) O N N N CH 3 Creatinine (0.5 2g) O O O OH O Creatine (0.5 2g) OH Ketone Bodies (3 15mg) OH Uric acid (0.3 1g)

5 Fenton s Reagent 2H 2 O 2 2H 2 O + O 2 Fe 2+ + H 2 O 2 Fe 3+ + HO + HO Fe 3+ + H 2 O 2 Fe 2+ + HOO + H + HO R H R + H 2 O + COOH CO 2 NO 3 SO 4 2 2HO H 2 O 2 2H 2 O + O 2 Fenton s Reagent Revisited, C. Walling, Accounts of Chemical Research, 8, (1975). Determination of Hg in Water and Urine by Gold Film Sensor Following Fenton s Reagent Digestion, L. Ping, P.K. Dasgupta, Anal. Chem., 61, (1989). Fenton Digestion of Milk for Iodinalysis, C.P. Shelor, et al., Anal. Chem., 83, (2011).

6 Peroxide Consumption vs Temperature Reaction Rate (g H 2 O 2 /L/min) Temperature ( o C) Destruction of Ion Exchange Resin in Waste from the HFIR, T1, and T2 Tanks Using Fenton s Reagent, P.A. Taylor, ORNL/TM 2002/197.

7 Gas Evolution vs Time 25 Gas Concentration (vol%) CO 2 O Time (Hours) Destruction of Ion Exchange Resin in Waste from the HFIR, T1, and T2 Tanks Using Fenton s Reagent, P.A. Taylor, ORNL/TM 2002/197.

8 Application to Urine Digestion 25mL Urine sample in 50 ml polypropylene centrifuge tube 25mg Fe as Fe(NH 4 ) 2 (SO 4 ) mL conc. H 2 SO 4 2mL 0.25M Fe(II) in 2M H 2 SO 4 100uL 1 octanol (anti foam) 5mL cold 30% H 2 O 2 Ramp to 65 o C over 1hr Note: For safety, loosely cap vials to allow offgassing. Digest in well vented area/hood. Ramp to 85 o C over 1hr (Destroy Residual H 2 O 2 ) Chemical separation or direction autodeposition on copper

9 Timeline Qualitative Cold Tests (Color/Smell/Residue) Spike Fresh/Aged Urine (High Level 210 by LSC) 210 Spiked/Aged Difficult Urine (3 months) Add 208/209, Digest, Analyze Troubleshoot Repeat D. R. McAlister and E. P. Horwitz, Chromatographic radionuclide generator systems for the Actinides and Natural Decay Series Elements, Radiochimica Acta, 99, (2011). J. Harvey, J. A. Nolen, T. Kroc, I. Gomes, E. P. Horwitz, D. R. McAlister, Production of Ac 225 via high energy proton induced spallation of Th 232, Proceedings of Application of high energy proton accelerators, Fermilab, Chicago, IL, October 19 21, eds. Rajendran Raja and Shekhar Mishra, pp (2009).

10 sample Add Fe/H 2 O 2 65 o C 85 o C Ascorbic Acid

11 Autodeposition Cleaned copper planchet (alcohol, water, 1M HCl, water) Inverted 50mL c tube with drilled vent Quench H 2 O 2 with 1 2mL 1M ascorbic acid Add 1mL 9M HCl Heat to 90oC/Mix 1 3hrs Remove solution, rinse planchet, dry

12 210 FWHM = kev 208 Autodeposition recoveries from raw spiked urine samples Fresh Sample Aged Sample 2 13 % % 209

13 Recovery By Autodeposition (Fenton s Digest) % Rec. % Rec. % -210 Replicate % corr average SD mL urine sample (aged/difficult) Fenton's digest 25mg Fe 2mL 1M Ascorbic acid quench cleaned/polished copper 3hr at 85C 0.66Bq Bq hour count time

14 Recovery By Autodeposition (DI Water) 25mL DI Water Direct Spike 2mL 1M Ascorbic acid quench cleaned/polished copper 3hr at 85C 0.66Bq Bq hour count time Replicate % -209 % average SD 8 4

15 10 6 k' on DGA Resin Chemical Separation Fenton s Digestion 10 5 HCl Oxidative quench of H 2 O Concentrate with Fe(OH) 3 k' Acidify (HNO 3 ) or HCl (TRU) DGA Separation 10 1 HNO 3 BiPO 4 microprecipitation [Acid], M S.L. Maxwell, B.K. Culligan, J.B. Hutchison, R.C. Utsey, D.R. McAlister, Rapid Determination of 210 in Water Samples, Radioanalytical and Nuclear Chemistry, 298(3), , (2013).

16 H 2 O 2 Quench/Precipitation Precipitate Oxidizing Reducing No Oxidation Fe(OH) 2 NaOCl Fe(OH) 3 Fe(OH)x Phosphate* *25mg Fe/25mg Ca W. Liu, et al., Optimal Methods for Quenching Residual H 2 O 2 Prior to UFC Testing, Water Research, 37, (2007).

17 k' on DGA Resin from 1500mg/L Fe(III) h, 21(1) o C, um k' on DGA Resin from 4M HCl 10 5 (NH 4 ) 3 PO HCl 10 4 Ca(II) k' M HNO 3 HNO 3 k' Fe(III) 4M total Cl - HCl/MCl x 1M Al(NO 3 ) [Acid], M [Salt], M

18 % Recovery Recovery of from Fenton's Reagent Digest 25mg Fe, 2hr, Direct Acidification Recovery from DGA w/o Fenton s Digest <5% 25mL Fresh Urine 25mL 2yr Unpreserved Urine (w/ solids) ml 30% H 2 O 2

19 FWHM = kev (Autodeposition) 2 3hrs 80 90% Recovery 208 FWHM = kev (BiPO4, 125ug) 30min >95% Recovery

20 Recovery By DGA/BiPO4 (Fenton s Digest) % Rec. % Rec. % -210 Replicate % corr average SD mL urine sample (aged/difficult) Fenton's digest 25mg Fe 2mL 10% NaOCl quench/ Fe(OH)3 ppt Load 25mL 8M HNO3 onto DGA resin BiPO4 ppt onto filter 0.66Bq Bq hour count time

21 Additional Matrices Aqueous samples and IX Resins have been demonstrated. EXC Resins more challenging. (Hydrophobic) Cellulose filters need H 2 SO 4 contact. Vegetation and Tissue, possible. Need physical decomposition first. How to solubilize fat? (Basic ph/different Metal Ion?). Fe, Cu, Mn, Ni Lyophilization? Larger Urine Samples/Additional Analytes.

22 Thank you!!!