ORBECO SP600, Instruction Manual, Page: 124 / 334

122 SP600 Spectrophotometer 01/2008
1.1 Methods
Formaldehyde
with MERCK Spectroquant
®
Test,
No. 1.14678.0001
0.02 – 1 mg/l HCHO
Use two clean, empty vials and mark one as blank for zeroing.
1. Pipette 4.5 ml reagent HCHO-1 into each vial.
(CAUTION: Reagent contains concentrated Sulfuric
acid! Note 4)
2. Add one level microspoon of HCHO-2 into each vial.
3. Close the vials with the caps tightly and shake vigorously
until the reagent is completely dissolved.
4. Fill 3 ml deionized water into one of the prepared
vials (this is the blank) .
5. Fill the second prepared vial with 3 ml of the water
sample (this is the test solution) .
6. Close the vials tightly and swirl several times to mix the
contents.
7. Press
[ ]
key.
Wait for a reaction period of 10 minutes .
After the reaction period is finished proceed as
follows:
8. Fill the 50 mm cell with the prepared blank .
9. Place the cell in the sample chamber making sure that
the positioning is correct.
10. Press
ZERO
key.
11. Remove the cell from the sample chamber. Empty the
cell and dry completely.
12. Fill the 50 mm cell with the test solution .
13. Place the cell in the sample chamber making sure that
the positioning is correct.
14. Press TEST key.
The result is shown in the display in mg/l Form-
aldehyde.
prepare Zero
press ZERO
Zero accepted
prepare Test
press TEST
Countdown
10:00
start:
1 7 6