ELTRA CS-2000, Руководство пользователя

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Maintenance
48
CAUTION
C14.0090
Risk of injury to eyes
Chemicals

When changing the chemicals, the smallest particles of chemicals may be
suspended in the air and cause damage to eyes.
•
Always wear protective goggles when working with chemicals.
•
Please heed the safety data sheets for the chemicals used.
Magnesium perchlorate (anhydrone)
as moisture absorber
Sodium hydroxide (ascarite) as CO2 absorber
Copper oxide on rare soils as oxidizer (CO

CO2)
The reagent tubes are replaced when they are saturated. See chapter General Information .
It is not possible to dry the magnesium perchlorate and use it again, as it is chemically changed
after reacting with the moisture. The saturation of the sodium hydroxide changes its color (it
turns to light grey).
The magnesium perchlorate is saturated if its particles do not move when tapping on the glass
tube. It is essential to change the absorber before it becomes cloggy. The moisture absorber
should be checked every 100-200 induction analyses and if necessary, it should be replaced
(glass tube underneath the metal filter).
Please refer to the following schematics to identify the glass tubes on the analyzer. In addition
to the reagents in the glass tube, fill the bottom end of the tube with glass wool. One should pay
attention that the glass wool should be only as thick as necessary. Otherwise the gas flow can
be choked. Under no conditions should the amount of glass wool be less than that shown in the
following schematics. Otherwise fine particles of magnesium perchlorate can pass through the
glass wool layer blocking the hole of the fitting underneath.
It should be pointed out that magnesium perchlorate is a very strong oxidizing material.
NOTICE
There are qualities of chemicals such as Anhydrone, ascarite, copper oxide, Schuetze reagent,
tungsten granules, iron chips, copper chips etc. which have been specially developed for
combustion analyzers and other analytical instruments. The commonly available materials fulfill
their specific purposes either inadequately or not at all.
• The magnesium perchlorate which is commonly available causes memory
effect and
affects repeatability. Another typical effect is that the analysis takes too long and it is often
not even completed. This effect also occurs with magnesium perchlorate of suitable quality
when it is saturated.
• The commonly available sodium hydroxide binds CO2 very inadequately at
room
temperature, whereas the special quality not only perfectly binds CO2 at room temperature
but also contains an indicator.
• The glass tubes and the O-rings should be lubricated with high vacuum silicon grease and
not with ordinary silicone grease.
The user is free to test commonly available materials; the analyzer will not be damaged. If
problems should arise, however, suitable materials, in proper, unsaturated condition, should be
used, before calling technical service.
The bottles with chemicals must be closed very tight, immediately after use, so that they do not
become saturated with air moisture or CO
2
.