ORBECO SP600, Instruction Manual, Page: 85 / 334

83
SP600 Spectrophotometer 01/2008
1.1 Methods
15. Fill a second clean vial (16 mm Ø) with 10 ml of water
sample
.
16. Add
one CHROMIUM HEXAVALENT powder pack
straight from the foil to the water sample.
17. Close the vial tightly with the cap and swirl several
times to mix the contents.
18. Fill the 50 mm cell with this test solution.
19. Place the cell in the sample chamber making sure that
the positioning is correct.
20. 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 in:
mg/l Cr (Vl)
mg/l Cr (lll)
mg/l Cr total chromium
Notes:
1. Performing steps 1–14 determines concentration of total chromium and steps 15–20
determines concentration of Chromium (VI). The concentration of Chromium (III) results
out of the difference.
2. pH value of the water sample should be between 3 and 9.
3. For information about interferences especially in waste water and chemical waste water
through metals and reductive or oxidic agents see DIN 38 405 – D 24 and Standard
Methods of Water and Wastewater, 20th Edition; 1998.
4. mg/l
μg/l
*,** mg/l Cr (VI)
*,** mg/l Cr (III)
*,** mg/l Cr tot.
T1 accepted
prepare T2
press TEST
Countdown
5:00
Ø 16 mm