Camlab Lovibond MD 610, Инструкция по эксплуатации

Страница: 131 / 371

125
MD 610_2d 11/2019
Notes:
1. Vial cleaning:
As many household cleaners (e.g. dishwasher detergent) contain reducing substances,
the subsequent determination of Hydrogen peroxide may show lower results. To avoid
any measurement errors, only use glassware free of Chlorine demand.
Preparation: Put all applicable glasswareinto Sodium hypochlorite solution (0.1 g/l) for
one hour, then rinse all glasswarethoroughly with deionised water.
2. Preparing the sample:
When preparing the sample, the lost of Hydrogen peroxide, e.g. by pipetting or shaking,
must be avoided. The analysismust take place immediately after taking the sample.
3. The DPDcolour development is carried out at a pH value of 6.2 to 6.5. The reagent
tablet therefore contains a buffer for the pH adjustment.
Strong alkaline or acidic water samplesmust be adjusted between pH 6 and pH 7 before
the tablet is added (use 0.5 mol/l Sulfuric acid resp. 1 mol/l Sodium hydroxide).
4. Exceeding the measuring range:
Concentrations above 5 mg/l Hydrogen peroxide can lead to results showing 0 mg/l.
In this case,the water sample must be diluted with water free of Hydrogen peroxide.
10 ml of the diluted sample should be mixed with the reagent and the measurement
repeated.
5. Oxidising agents such as Chlorine, Ozone etc. interfere as they react in the same way as
Hydrogen peroxide.
Reagent Form of reagent/Quantity Order-No.
Hydrogenperoxide LR Tablet / 100 512380BT