Application note
DOC 411-016
Triathler technical features
Version 1.1
Uranium - Extraction from 250 ml water
U-238 can be extracted from water with modified MaxiLight added with a few per cent (6 %) of a complexing agent, such as e.g.
bis(2-ethylhexyl)-phosphate (HDEHP), trioctylphosphine oxide (TOPO) or tributyl phosphate (TBP). Before extraction, water is
thoroughly bubbled to remove Rn-222 and made acidic with nitric acid. According to literature, these agents are rather effective
so that a few milliliters of the modified cocktail can extract over 90 % of U from one liter of water. LLoD in 1 hour: 1 µg/l or 0,01
Bq (U -238) / l
S29
S25
S21
S17
S13
S9
61
57
53
49
45
41
37
33
29
25
21
17
13
9
5
1
S5
S1
27-30
24-27
21-24
18-21
15-18
12-15
9-12
6-9
3-6
0-3
counts
.
45
40
35
30
25
20
15
10
5
0
200
U-238
U-234
ALPHA
BETA
400
600
800
1000
MCA channels
Activity of the sample: 3,36 mg/l or 42 Bq/l
Procedure
Organophosphorus compounds can extract U from acidified water.
–Bis-ethylhexyl phosphate (HDEHP).
–Tri-octylphosphine oxide (TOPO).
–Tributyl phosphate (TBP).
Prepare an extractive cocktail containing 5-10 % concentration of extractant in a hydrophobic cocktail.
Bubble the water thoroughly with clean air to remove Rn-222.
Take 50-1000 mL of water and add 5-30 mL extractive cocktail on it.
Shake, let phases separate and collect an aliquot of cocktail. Count