GE Analytical Instruments ©2016
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DLM 68100-09 EN Rev. A
Chapter 3. Interferences
Certain substances affect the safety, reliability, and analytical performance of the InnovOx TOC Analyzer if they
are present in the water sample.
Safety
Some water samples may contain species that form toxic products when they are acidified or oxidized. Species
such as cyanide (CN
-
), sulfide (S
-2
), and fluoride (F
-
) produce toxic gases when acidified. Samples that contain
those species should not be analyzed in the InnovOx TOC Analyzer.
Other interferences, including chloride (Cl
-
) and bromide (Br
-
) are oxidized in the Analyzer, forming toxic gases
that are discharged from the Analyzer in its waste stream. The waste must either be kept basic or immediately
discharged into an appropriate drain to avoid formation of toxic concentrations of those species in the air. If the
waste solution is collected, excess sodium carbonate or sodium hydroxide should be added to its container
before the analysis starts, and the waste container should be actively mixed or periodically agitated, to ensure
the solution remains basic. In either case, the Analyzer should only be used in well-ventilated areas.
Other compounds may react violently when they come in contact with the acid, oxidizer, or while being oxidized
in the reactor. Compounds such as hydrazine and hydrogen peroxide may generate excessive volumes of gas
during the oxidation. However, the InnovOx Analyzer can handle the additional pressure in the reactor
associated with gas-producing samples.
