3. Weigh sample 1-2 g to Teflon evaporation dish;
Add radioactive tracers: Th-229 and U-232
Add 20 mL HNO3 and evaporate to dryness (3 times)
Open Digestion
Add 20 mL HF and evaporate to dryness (2 times)
Add 20 mL HClO4 and evaporate to dryness (2 times)
Dissolve the residue with 20 mL 9 M HCl and
transfer the solution to a centrifuge tube
Separate the residue by centrifugation and decant
Wash the precipitate with 5 mL 9 M HCl and
separate the residue by centrifugation and decant (3 times)
Save the supernatant for the chemical separation process
4. Load sample
Rinse Th: 35 mL 9M HCl
Elute Pu: 50-60 mL
6M HCl + 0.26M HF
Elute U+Fe: 50 mL 0.1M HCl
Main Column
Main column
(Cl- column)
Biorad AG1-X8 12 mL
Prewash with
50-60 mL 9M HCl
Save for
Th
+ Th, Am, Ac, Al processing
Save for
U Pu
processing U+Fe Evaporate to dryness
and dissolve
Evaporate to dryness and dissolve with 5mL HNO3
with 2mL HNO3 + 2mL H2O + 5mL H2O
5. Load U fraction solution
Elute Fe & other contamination:
25 mL 8M HNO3
Elute U: 50 mL 0.1M HCl
U column
U Column
(NO3- column)
Biorad AG1-X8 12 mL
Prewash with
50-60 mL 8M HNO3
+ Fe & other contaminations
U Evaporate
to dryness
Repeat if
evidence of
Source preparation for
Fe present
alpha spectrometry
6. Load Th fraction solution
Elute contamination:
35-50 mL 8M HNO3
Elute Th: 50-60 mL 9M HCl
Th column
Th Column
(NO3- column)
Biorad AG1-X8 12 mL
Prewash with
50-60 mL 8M HNO3
+ Other contaminations
Th Evaporate
to dryness
Repeat if
evidence of
Source preparation for
contamination
alpha spectrometry
7. Final U/Th acidic fraction
Counting Source Preparation
Add 10 mL Ce carrier
(Cerous nitrate carrier in 0.1M HNO3 = 0.5 g Ce/mL solution)
Add 1-2 drops of Safranin O indicator
Add of 20% TiCl3 dropwise until solution becomes clear
Add 1mL conc. HF
Allow to precipitate for 20-30 minutes
Filter with 0.1 m Metricel filter
Dry at 60 C for 10 minutes
Mount the filter on a stainless steel disc
Ready for Alpha spectrometry
