Lovibond Tintometer MD 100 Manual De Instrucciones página 22

Chemical Method
Dichromate / H SO
2 4
Appendix
Interferences
Persistant Interferences
• In exceptional cases, contents, for which the oxidation capacity of the reagent is not
sufficient, can lead to lower results.
Removeable Interferences
• Suspended solids in the vial can lead to incorrect measurements and so to avoid
this, it is important to place the vials carefully in the sample chamber as the method
necessitates a build-up of precipitate at the bottom of the vial.
• The outer walls of the vial must be clean and dry before the analysis is carried out.
Fingerprints or water droplets on the vial lead to incorrect measurements.
• In the standard version, chloride interferes from a concentration of 1000 mg/l. In the
mercury-free version, the disturbance depends on the chloride concentration and
the COD. Concentrations from 100 mg/l chloride can lead to significant disturbances
here. To remove high chloride concentrations in COD samples, see method M130
COD LR TT.
Conformity
ISO 15705:2002
According to
ISO 15705:2002
DIN 38409 part 41
Reactor is necessary for COD (150 °C), TOC (120 °C) and total -chromium, - phosphate, -nitrogen, (100 °C)
b)
EN Method Reference Book 1.0
COD LMR TT / M133
EN
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