Camlab Lovibond MD 610, Инструкция по эксплуатации

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MD 610_2d 11/2019
Notes:
1. Thehydrogen peroxide is determined in the form of yellow/orange coloured peroxotitanic
acids in strongly acidic media. In connection with neutral to weakly alkaline (~pH 10)
samples, the acid in the reagent is sufficient in order to produce a medium suitable for
measurement. In the case of strongly alkaline samples (pH > 10), the samples must be
acidified before measurement otherwise the results may be deficient. This is achieved
by diluting the sample with a 5% sulphuric acid solution, for example, at a ratio of 1:1.
In contrast to many other colour reactions, in connection with the presenceof hydrogen
peroxide, discoloration with long-term stability is achieved that can still be measured
after 24 h. Particlesin the sample solution or turbidity distort the analysis and must be
eliminated by centrifuging or simply filtering the sample solution prior to performing the
measurement. Falsification of the measurement resultsshould alsobe expectedin connection
with coloured solutions.
2. Oxidising agents such as chlorine, bromine, chlorine dioxide and ozone do not distort the
analysis.On the other hand, however, water discoloration doesdistort the analysis.In thiscase,
proceed as described in the following:
• Filla clean vial (16 mm Ø) with 10 ml of the water sampleand perform zero calibration
(see“Operation”).
• Measure the sample solution without the addition of drops of reagent ( result B).
• Then the same sample solution, measured with the addition of the reagent drops
(
result A).
• Calculations: mg/l H
2
O
2
= result A – result B
3. Attention: Thereferencereagent containsa 25% sulphuric acid solution. It isrecommended
to wear appropriate protective clothing (protective goggles/gloves).
Reagent Form of reagent/Quantity Order-No.
H
2
O
2
-reagent Liquid reagent / 15 ml 424991