ORBECO SP600, Instruction Manual, Page: 87 / 334

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SP600 Spectrophotometer 01/2008
1.1 Methods
Chromium, total (Cr(lll) + Cr(Vl))
with Powder Pack
0.005 – 0.5 mg/l Cr / 5 – 500 μg/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. Fill a clean 50 mm cell with deionized water .
7. Place the cell in the sample chamber making sure that
the positioning is correct.
8. Press ZERO key.
9. Remove the cell from the sample chamber. Empty the
cell and dry completely.
10. Add
one CHROMIUM HEXAVALENT powder pack
straight from the foil to the pre-prepared water
sample.
11. Close the vial tightly with the cap and swirl several
times to mix the contents.
12. Fill the 50 mm cell with this test solution.
13. Place the cell in the sample chamber making sure that
the positioning is correct.
14. Press TEST key.
Wait for a
reaction period of 5 minutes
.
After the reaction period is finished the measurement
starts automatically.
The result is shown in the display as total Chromium.
Ø 16 mm
prepare Zero
press ZERO
Zero accepted
prepare Test
press TEST
Countdown
5:00
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