2 chemical resistance and materials, 1 solutions, 2 body – Metrohm 806 Exchange Unit User Manual
Page 33: 3 materials, Chemical resistance and materials, Solutions, Body, Materials

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5 Handling and maintenance
806 Exchange Unit
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25
5.2
Chemical resistance and materials
Metrohm exchange units are designed for usage with aqueous solutions
and the most common solvents.
The temperature of the dosing material may not exceed 50°C. The
exchange unit and its components cannot be autoclaved. The sterility of a
germ-free dosing material cannot be guaranteed.
5.2.1
Solutions
With the 806 Exchange Unit various solutions can be dosed. The materials
of the individual components used have been selected for maximum
resistance to chemicals and functionality.
It can however not be assumed that all types of aggressive or high-con-
centration solutions can be conveyed without difficulty. It is the responsi-
bility of the user to determine the resistance of the various individual com-
ponents to specific, aggressive media.
Many problems involving aggressive media can be prevented by regular
cleaning and inspections.
5.2.2
Body
The body is made of polybutylene terephthalate. It is only partly resistant
to chemicals.
Good resistance
Acids, organic solvents
Limited resistance
Alkalis (with a conc. > 1 M)
The exchange unit is not dishwater-safe. In most cases, the exchange unit
is to be cleaned with lukewarm water and dishwashing detergent.
5.2.3
Materials
Body
PBT (polybutylene terephthalate)
Dosing piston
PTFE (polytetrafluoroethylene)
Dosing cylinder
Borosilicate 3.3
Flat stopcock
PCTFE/PTFE or ceramic
Light protection
PETG (polyethylene terephthalate, glycol-modi-
fied) or PVDF