1. Optimizing Radiochemical Methods at SRS
Sherrod L. Maxwell, III
Westinghouse Savannah River Company

2. Recent Improvements SRS Environmental Monitoring lab
new actinide methods for water, air filters, soil, sediments, sanitary sludge
SRS Bioassay lab (with Dave Fauth)
increased Pu-Np recoveries
faster fecal method (HEDPA-no microwave)
F/H Laboratory (Process lab)
faster single column separation for Pu/Np in high U samples (U-234 removal of 1E6)

3. SRS Environmental Monitoring Lab
Stacked TEVA + TRU cartridges for all matrices
Replaced UTEVA+TRU
water samples
air filter samples
soil, sediments (up to 10 grams)
sanitary waste sludge (5 grams)
vegetation (10 grams)
fruit (100 grams)

4. Advantages of TEVA+TRU
Pu, Np, Am, Cm, U (Th) in a single stacked column
Allows Pu and Np together on TEVA (Pu-236 tracer)
High retention of Pu, Np on TEVA
Higher retention of U on TRU vs. UTEVA
Better Po-210 removal (interferes with U-232) and Th removal
Removal of TEVA/removal on TRU if any residual

5. Pu, Np, Am, Cm,U, Sr on TEVA/TRU RESIN (Water/Air filters)
1) Redissolve in mL 3M HN M to 1M Al(NO3)3
2) Add 0.5 mL 1.5M Sulfamic Acid + 1 mL 1.5M Ascorbic Acid
3) Add 1 mL 3 M Sodium Nitrite
Th Elution
20mL 9MHCI
Rinse
20 mL 3MHN03
Pu, Np Elution
20mL
0.10MHC MHF M TiCl3
Add 0.5 mL 30 wt% H2O2
2mL TEVA Resin
( um)
Remove TRU cartridge:
1) Elute Am with
15mL 4M HCI
2) 10 mL 4MHCL-0.2M HF
to remove any Th
2) Elute U with
15mL 0.1M ammonium
bioxalate
Cerium fluoride
Alpha spectrometry
2.0mL TRU-Resin
( um)
Collect, evaporate, dissolve in 8M HNO3
Sr Resin

6. Alpha Resolution Improvements
Strong HCL can cause extractant bleed-off
TEVA: 5 mL 3M HNO3 rinse after 9M HCL Th removal rinse prior to stripping Pu and Np
TRU:
4M HCL extractant bleed-off affects resolution (worse with 9M)
We have gone back to evaporating 4M HCl with con HNO3 and 100 uL of 1.8M H2SO4, then ash with con HNO3 and H2O2, redissolve in 0.5M HCL
3M HNO3 rinse after 4M HCl-0.2M HF rinse
UTEVA/TRU:
Using 9M HCl with UTEVA or TRU can affect bleed-off and peak resolution/not needed

7. Total Dissolution Soil, Sediments, Sludge
Actinides in soil, sediment and sanitary sludge samples
5 to 10 gram soil
5 gram sanitary sludge
Replaced fusion method which had poor recoveries, load solution problems, and Po-210 problems
Total Dissolution
sodium peroxide/sodium hydroxide fusion (15-20 minutes)
multiple samples fused at once in furnace
inexpensive zirconium crucibles

8. Total Dissolution Soil, Sediments, Sludge, contd.
Total Dissolution and matrix removal (1 day)
soils: heat at 550C, then nitric acid/HF silicon removal first, then fusion
sanitary sludge: heat at 550C, then fusion
fusion in zirconium crucibles for 20 minutes at 700C
10 grams sodium peroxide/5 grams sodium hydroxide
Hydroxide precipitation with TiCl3 reductant and barium present to eliminate carbonate interference

9. Total Dissolution Soil, Sediments, Sludge, contd.
Redissolve in dilute HCl and perform cerium fluoride precipitation (500 ug to 2 mg Ce) with TiCl3 present
Rinse precipitate with 0.25M HCl- 6MHF with 0.02M rongalite present
Soil load solution: 5 mLs 3M HNO3-0.25M boric acid, 6 mL 7M HNO3, 7.5 mL 2M AL(NO3)3

10. Transfer to crucible after silicon removal

11. 10 grams sodium peroxide + 5 grams sodium hydroxide
700C for 20 minutes

12. Just add water after cooling briefly

13. Dilute to 1 liter with water with iron
carrier, TiCl3, and barium present

14. After centrifuging, acidify
and add TiCl3, Ce and HF.

15. Place on ice, then centrifuge

16. Rinse with dilute HCl,
HF with rongalite present

17. Redissolve in acid, boric acid
and aluminum nitrate

18. Cerium fluoride / Alpha spectrometry
Actinides in SOIL
1) Redissolve in 18.5 mL 3M HN M Al(NO3) M boric acid
2) Add 0.5 mL 1.5M Sulfamic Acid mL 1.5M Ascorbic Acid
3) Add 1 mL 3 M Sodium Nitrite
Rinse
Beaker rinse: 3mL 5MHN03
Separate cartridges:
TEVA: 5 mL 3MHN03 Collect/acidify -
with 2 mL16M HN03 then to TRU
TEVA:10 mL5M HNO3
8 mL3M HN03
Th Elution
20mL 9MHCI
Pu Elution
20mL
0.10MHC MHF M TiCl3
Remove TRU cartridge:
1) Elute Am with 15mL 4M HCI
2) Add 3M HNO3 rinse from TEVA
3) 10 mL 6M HNO3 -remove any Po-210
4) 15 mL 4M HCl-0.2M HF-remove Th
5) Elute U with 15mL 0.1M ammonium
bioxalate
Add 0.5 mL 30 wt% H2O2
2mL TEVA Resin
( um)
Cerium fluoride
Alpha spectrometry
2.0mL TRU-Resin
( um)
Cerium fluoride / Alpha spectrometry

19. (warm and rinse original beaker)
Am/RE Removal on TEVA
1) Evaporate 4M HCl with 5mL con.HNO3, 50 uL of 1.8M H2SO4, then ash with nitric acid and hydrogen peroxide
2) Redissolve in 5 mL of 4M NH4SCN, warm gently.
Rinse
Beaker rinse: 3mL 4M NH4SCN, warm
10 mL 1.5 M NH4SCN to column
Am Elution
25 mL 1M HCl
(warm and rinse original beaker)
2mL TEVA Resin
( um)
Cerium fluoride
Alpha spectrometry

20. Final Am Clean-up on TEVA

27. QAP 0903-SOIL
SRS EML Ratio Pu Pu Am U U
Results in Bq/kg
5 gram sample analyzed

28. Bioassay Lab Improvements
Actinides and Sr-90 in urine
stacked TEVA+TRU Resin cartridges with vacuum boxes
Pu-236 tracer for Pu and Np at same time
Pu, Np (TEVA) and U, Am (TRU)
Sr (Sr Resin)
Pu stripping improvement:
Increased rongalite to 0.04M (sodium formaldehyde sulfoxylate) -
compatible with electroplating
adjust bisulfate added for sulfate added from rongalite decomposition (2.0 mLs 10 % bisulfate instead of 3 mLs)

29. Bioassay Lab Urine Method Tracer Recoveries Pu EU Sr Am Np

30. Recent Improvements in Fecal Method
HEDPA strip of Diphonix instead of microwave destruction (18 mL 0.5M HEDPA)
45 minute hot plate destruction
30 mL of 30 wt% H2O2
Add 200 uL of 1.5M ferrous sulfate
1 mL of concentrated HNO3
Ash to dryness
Add 5 mL concentrated HNO3, ash to dryness
Add 5 mL 30 wt% H2O2, ash to dryness. Repeat 3 more times.
Faster than microwave, but requires more aluminum in load solution due to higher phosphate

31. Process Lab Improvements
Process samples to support HEU Blenddown processing
Pu and Np are key product specification measurements
Pu-236 tracer for Pu and Np on TEVA resin in HEU and LEU process solutions
Improvements:
Single cartridge instead of two column method
use Ti (III) reductant in Pu strip from TEVA
Using 0.5mL 30wt% H2O2 instead of nitrite, much better oxidation of U+4 to U+6
1000 x removal of residual U in cerium fluoride precipitation
$100K savings-labor and materials

32. Summary Future work SRS Environmental Monitoring lab work
TEVA+TRU for all matrices
Cerium fluoride matrix elimination
Bioassay lab
Improved Pu stripping using rongalite (95% recoveries)
HEDPA to eliminate microwave in fecal analysis (save 1-2 days)
Process lab
Single cartridge separation for Pu, Np in process lab on high uranium samples (cost/time savings)
Future work
Ra on MnO2 resin

33. MnO2 Resin