THE RADIOCHEMISTRY OF PLUTONIUM - Sciencemadness.org

Procedure 12. Plutonium from Environment al Water Samples J. Scheidhauer,
L. Messanguiral, and A. M. Meiraneisio (Ref. 352)
Outline of Method
Pu(IV) is spearated by chemisorption on solid C aF2 as the concentration
step, and further purified with two TTA extraction cycles. The chemisorption step
has been shown to be quantitative and very efficient. The sensitivity can be made very
great, as low as 0.7 X 10-11 p Ci/ml by taking a large sample.
Reagents
Procedure
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Concentrated nitric acid (d = 1.38)
10 N nitric acid
—
2 h’ nitric acid
—
1 N nitric acid
—
Concentrated hydrofluoric acid
Concentrated perchloric acid
Ferric nitrate
Hydroxylamtie hydrochloride
1 ~ hydroxylamine hydrochloride
Sodium nitrite
Ammonium thiocyanate
2 ~ A1(N03)3 - 0.5 & HN03
Calcium fluoride
Solution of 111 g/1 TTA in xylene
Place 3 liters of filtered water to be analyzed in a beaker and add 5 g each
of ferric nitrate ad ~ydroxylamine hydrochloride.
Heat and agitate with a glass stirring rod to about 60-7@C.
Let the solution cool down, making sure the Fe ‘++ is reduced by spot
testing with several crystals of ammonium thiocyanate from time to time.
Pour this solution in a plexiglass column which is closed at one end and
add water to within 0.5 cm of the top. Start agitation with a magnetic
stirrer.
Add 10 g sodium nitrite. After several minutes add 60 ml concentrated
HN03 ( d = 1.38), then 45 ml concentrated HF when the HN03 has redis-
solved the ferric hydroxide which has formed.
Then add 0.2 g calcium fuloride powder and place the filtration system on
the column (see Fig. 58).
After agitating for 1 hr, invert the column over a 5-10 liter plastic receitig
vessel. The filtration may be speeded by maintaining pressure by means
of a laboratory pump.
Wash the filter cake two times with 250 ml of distilled water introduced
into the tube under pressure.
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