Thermo Scientific AQUAfast AQ3700, User Manual

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Thermo Scientific Orion AQUAfast AQ3700 Colorimeter User Guide
1.1 Methods
Notes:
1. Before use, clean the vials and the measuring beaker with Hydrochloric acid
(approx. 20%). Rinse them thoroughly with deionized water.
2. To get accurate results the sample temperature must be between 20°C and 25°C.
3. A low test result may be given in the presence of Fluorides and Polyphosphates.
The effect of this is generally insignificant unless the water has fluoride added artificially.
In this case, the following table should be used:
Fluoride
[mg/l F] Displayed value: Aluminium [mg/l Al]
0.05 0.10 0.15 0.20 0.25 0.30
0.2 0.05 0.11 0.16 0.21 0.27 0.32
0.4 0.06 0.11 0.17 0.23 0.28 0.34
0.6 0.06 0.12 0.18 0.24 0.30 0.37
0.8 0.06 0.13 0.20 0.26 0.32 0.40
1.0 0.07 0.13 0.21 0.28 0.36 0.45
1.5 0.09 0.20 0.29 0.37 0.48 ---
Example: If the result of Aluminium determination is 0.15 mg/l Al and the Fluoride
concentration is known to be 0.4 mg/l F, the true concentration of Aluminium is
0.17 mg/l Al.
4. Al
Al
2
O
3