ORBECO SP600, Instruction Manual, Page: 88 / 334

86 SP600 Spectrophotometer 01/2008
1.1 Methods
Chromium, differentiated
determination with Powder Pack
0.02 – 2 mg/l Cr
Digestion:
1. Fill a clean vial (16 mm Ø) with 10 ml of the water sam-
ple .
2. Add one PERSULF.RGT FOR CR powder pack straight
from the foil into the vial.
3. Close the vial tightly with the cap and swirl several
times to mix the contents.
4. Heat the vial for 120 minutes in a preheated thermo-
reactor at a temperature of 100°C .
5. Remove the vial from the thermoreactor.
(CAUTION: The vials are hot!).
Invert the vial and allow to cool to room temperature.
Performing test procedure:
6. Place the pre prepared vial in the sample chamber
making sure that the marks are aligned.
7. Press ZERO key.
8. Remove the vial from the sample chamber.
9. Add
one CHROMIUM HEXAVALENT powder pack
straight from the foil into the pre prepared vial.
10. Close the vial tightly with the cap and swirl several
times to mix the contents.
11. Place the vial in the sample chamber making sure that
the marks are aligned.
12. Press
TEST
key.
Wait for a reaction period of 5 minutes .
After the reaction period is finished the measurement
starts automatically.
Ø 16 mm
prepare Zero
press ZERO
Zero accepted
prepare T1
press TEST
Countdown
5:00
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