Thermo Scientific AQUAfast AQ3700, User Manual

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0 Thermo Scientific Orion AQUAfast AQ3700 Colorimeter User Guide
1.1 Methods
Phosphate, total
with Digestion Tube Test
0.02 – 1.1 mg/l P (= ^ 0.06 – 3.5 mg/l PO
4
)
Insert the adapter for 16 mm Ø vials.
1. Open the white cap of one digestion tube PO4-P Acid
reagent and add 5 ml of the water sample .
2. Add the contents of one Potassium Persulfate F10
Powder Pack straight from the foil to the vial (Note 2).
3. Close the vial tightly with the cap and invert several
times to mix the contents.
4. Heat the vials for
30 minutes
in the preheated reactor
at a temperature
of 100°C
.
5. After 30 minutes remove the vial from the reactor.
(CAUTION: The vials are hot!)
Allow the vials to cool to room temperature.
6. Open the cooled digestion vial and add 2 ml 1.54 N
Sodium Hydroxide Solution to the vial.
7. Close the vial with the cap and invert gently several
times to mix the contents.
8. Place the vial in the sample chamber making sure that
the
l
marks are aligned.
9. Press ZERO key.
10. Remove the vial from the sample chamber.
11. Add the contents of one Phosphate Rgt. F10 Powder
Pack
straight from the foil to the vial (Note 2).
12. Close the vial tightly with the cap and swirl several times
to mix the contents (approx. 10-15 sec., Note 3).
13. Place the vial in the sample chamber making sure that
the
l
marks are aligned.
14. Press
TEST
key.
Wait for a
reaction period of 2 minutes
.
After the reaction period is finished the measurement
starts automatically.
The result is shown in the display in mg/l total Phosphate.
prepare Zero
press ZERO
Zero accepted
prepare Test
press TEST
Countdown
2:00
1 2
3 4
Ø 16 mm
2 6 3