Rapid Actinide Analysis for Large Soil Samples-Update Sherrod L. Maxwell, III Westinghouse Savannah River Company
SRS Soil Method Total Dissolution High recoveries Faster Sample preparation Good alpha resolution Effective removal of interferences such as Th isotopes and Po-210
Update-Improvements Enhancements to improve precipitation steps Better Am recovery for difficult samples –DGA Resin added to column method
Transfer to crucible after silicon removal
10 grams sodium peroxide + 5 grams sodium hydroxide 700C for 20 minutes
Just add water after cooling briefly
Dilute to 1 liter with water with iron carrier (increased to mg), TiCl3, and barium (1.5 mL of 10%) present, add 5-10 mg Ce
After centrifuging, acidify and add TiCl3, Ce (2mg) and HF.
Place on ice, then centrifuge
Rinse with 0.25M HCL- 3.8M HF-0.04M rongalite
Redissolve in acid, boric acid and aluminum nitrate
Actinides in Soil Rinse Beaker rinse: 3mL 6MHN0 3 Separate cartridges: TEVA: 5 mL 3MHN0 3 Collect/acidify - with 2 mL16M HN0 3 then to TRU TEVA:10 mL 5M HNO 3 Discard 10 mL 3M HN0 3 Discard Th Elution 20mL 9MHCI Pu (and/or Np) Elution 20mL 0.10MHC MHF M TiCl3 1)Redissolve in 5 mL warm 3M HN M boric acid, add 6mL 7M HNO3 and 7.5 mL 2M Al(N0 3 ) 3 2)Add 0.5 mL 1.5M Sulfamic Acid mL 1.5M Ascorbic Acid 3)Add 1 mL 3.5 M Sodium Nitrite 2 mL TEVA Resin ( um) 2 mL TRU-Resin ( um) Alpha spectrometry Cerium fluoride Add 0.5 mL 30 wt% H2O2 2 mL DGA-Resin ( um)
Actinides in Soil with DGA Remove TRU and DGA cartridge: 1) Rinse TRU+ DGA with 3 mL of 3M HNO3 and discard rinse. 2) Elute any U from DGA only with 6 mL of 0.25M HNO3 (then add 5 mL con. HNO3 to adjust acid) 3) Elute Am from DGA only with 10 mL 0.1M HCl. Add 4 mL of con. HCl to soln. To adjust acid to 3.5 M HCl. 4) Add DGA strip solution (con HCL added) to TRU to strip Am from TRU, recombine Am. Rinse TRU with 3M HCl.
Actinides in Soil with DGA, Cont. 5) Add 3M HNO3 rinse (then adj. ~7M HNO3) from TEVA to load to TRU 6) Add U fraction from DGA adjusted to ~ 7M HNO3 to add any U from DGA to TRU and remove any Po ) Add 18 mL 4M HCl-0.2M HF to TRU to remove Th 8)Elute U with 15mL 0.1M ammonium bioxalate
Load with TEVA+TRU+DGA Split Apart TEVA and TRU/DGA
Rinse, then strip Pu from TEVA Strip Am/Cm from DGA/add acid/then pass thru TRU
Am/RE Removal on TEVA Rinse Beaker rinse: 3mL 4M NH 4 SCN, warm 10 mL 1.5 M NH 4 SCN to column Am Elution 25 mL 1M HCl (warm and rinse original beaker) 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 NH 4 SCN, warm gently. 2mL TEVA Resin ( um) Alpha spectrometry Cerium fluoride
Final Am Clean-up on TEVA
10 g sample
5 g sample- Resolve Filters
5 g sample-Resolve Filters
MAPEP sample with DGA
MAPEP sample with DGA
MAPEP sample with DGA
Summary Enhanced precipitation steps –Cerium added during iron hydroxide ppt. Increased for sandy samples –Increased barium during iron hydroxide ppt. –lower HF/increased rongalite in final rinse of cerium fluoride ppt. Improved Am recoveries –DGA resin