Remove the silica from the filter paper and dry in a 110°
oven overnight. Break up the aggregated material with a
portar and pestle, then transfer to a 20 el platinum dish.
‘* 7
166
Moisten the silica with 10% H,S0,, then add about 100 ml f OF.
yo.
17.
Evaporate on & sand bath to 303 fumes to volatilize the
dlica.
Cool and Milute with distilled water, transferring the repulting solution to the original soil fiitrate, and add 20
Sr**
carrier.
.
18.
Weutralize the filtrate with NaOH pellets until the pH i
At tnis point add slowly, with stirring, SO grams of May
allow the precipitate to settle. Filter through No. 5
paper with suction and discard the filtrate.
9.
When the precipitate is dry, remove from the filter pa
transfer to the original beaker.
and
Dissolve in 200 ml of qdoncen-
trated EC1 and evaporate slowly to dryness.
Do not bake
20.
Mow add L460 ml of distilled water and stir mechanically
21.
Add slowly, 1540 ml of 90% BRO. with continuous mechanich] stir
22.
Allow to settle until the supernatant is clear, then decBnt as
23.
Transfer the precipitate and remaining acid to a 250 ml
the residue is completely dispersed.
fmtil
ring and allow to remain stirring for 1/2 hour.
much 75% HNOs as poasible.
fuge bottle, centrifuge and decant, discarding the sup
2h. Carry out another 75% HNO, separation using a volume of
25,
At this point the bulk of the calcium should be removed
strontium nitrate and insoluble material.
Add 10C ml
distilled water to the precipitate, centrifuge and deca
a 2530 wl beaker.
26.
s
Se
ry
2
Bee
Wash again with 530 ml of hot distilled water adding the [supernatant liquid to the beaker after centrifugation.
can now be discarded.
The
gesidue
_‘Bvaporate the filtrate slowly to dryness.
bens SY
UNCLASSIFIED
z
b0131986 OS
1057080
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