Camlab Lovibond MD 610, Инструкция по эксплуатации

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MD 610_2d 11/2019
Notes:
1. Temperature of the sample should be 15°C – 25°C.
2. If Silica or Phosphate is present a yellow colour is developed
3. In this step any yellow colour due to Phosphate is removed.
4. Interferences:
Substance Interference
Iron large amounts interfere
Phosphate does not interfere at concentrations lessthan 50 mg/l PO
4
at 60 mg/l PO
4
the interference is approx. – 2%
at 75 mg/l PO
4
the interference is approx. – 11 %
Sulfide interferes at all levels
Occasionallywater samplescontain forms of silica which reacts very slowly with
Molybdate. The nature of these forms is not known.
A pre-treatment with Sodium hydrogencarbonate and then with Sulfuric Acid will
make these forms reactive to Molybdate (pre-treatment is given in “Standard Methods
for the Examination of Water and Wastewater” under “ SilicaDigestion with Sodium
Bicarbonate”).
5. SiO
2
Si
Reagent Form of reagent/Quantity Order-No.
Set
VARIO Silica HR Molybdate F10
VARIO Silica HR Acid Rgt F10
VARIO Silica HR Citric Acid F10 Powder Pack / 100
Powder Pack / 100
Powder Pack / 100
535700