Metrohm 881 Compact IC pro – Anion - Manual (Page 73)

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5 Operation and maintenance
881 Compact IC pro – Anion
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5.3 Door
Caution
The door is made of PMMA (polymethylmetacrylate). It must never be
cleaned with abrasive media or solvents.
Caution
Never use the door as a handle.
5.4 Eluent
5.4.1 Production
The chemicals used for the production of eluents should have a degree of
purity of at least "p.a.". Only ultra pure water (resistance > 18.2 M
Ω *cm)
may be used for dilution (this generally applies for reagents which are
used in ion chromatography).
Newly produced eluents should always be microfiltered (filter 0.45 µm).
Caution
Only microfiltered (filter 0.45 µm) eluents may be used.
The composition of the eluent has a crucial effect on the chromatographic
analysis:
Concentration An increase in the concentration generally leads
to shorter retention times and faster separation,
but also to higher background conductivity.
pH pH changes result in shifts in the dissociation
equilibria and hence changes in the retention
times.
Organic solvents The addition of an organic solvent (e.g. metha-
nol, acetone, acetonitrile) to aqueous eluents
generally accelerates lipophilic ions.