Cleaning For Trace Analysis - VITLAB Dispenser TA2 Mode D'emploi

13. Cleaning for Trace Analysis

Before use in trace analysis, the instrument must first be thoroughly
cleaned. Pure chemicals used for analytical purposes are used for this
cleaning procedure. If contamination of the bottle contents must be
avoided, use the instrument without the recirculation valve. If the
instrument is used with the recirculation valve, it must be cleaned in
both dispensing and recirculation modes (Fig. 1 and 2).
Good results have been obtained in practice with the following
recommended cleaning procedures. They can be modified according
to need.
Screw the instrument onto a bottle filled with Acetone, prime it
1.
and then fill it completely.
Leave the piston at the upper stop and close the dispensing tube
with the screw cap.
After approx. 24 hours contact time, dispense twice, then
completely empty the instrument and rinse it five times with pure
water.
Screw the instrument onto a bottle filled with 20% hydrochloric
2.
acid, prime it and then fill it completely. Leave the piston at the
upper stop and close the dispensing tube with the screw cap.
3. After approx. 24 hours contact time, dispense twice, and then fill it
up again completely.
4. Repeat step 3 twice more.
After another approx. 24 hours contact time, completely empty
the instrument and rinse it five times with pure water.
Repeat steps 2 to 4 with 30% nitric acid.
5.
6. Screw the instrument onto a bottle filled with the desired dispen-
sing medium, prime it, and then fill it completely. Leave the piston
at the upper stop and close the dispensing tube with the screw
cap.
7. After approx. 24 hours contact time, dispense twice, and then fill
it up again completely.
8. Repeat step 7 twice more. After another approx. 24 hours contact
time, dispense twice and then leave the piston at the lower stop.
Note:
If the cleaning is not sufficient, repeat the cleaning procedure.
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