Metrohm 861 Advanced Compact IC - Manual (Page 77)

4.1 Practical notes on ion chromatography
861 Advanced Compact IC / Instructions for Use 8.861.1033
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Storage
Always store the separating columns sealed when not in use and filled
in accordance with the manufacturer’s specifications.
Regeneration
If the separation properties of the column have deteriorated, it can be
regenerated in accordance with the column manufacturer’s specifica-
tions. With the separating columns available from Metrohm (see
Metrohm’s “Range of IC columns”), the instructions for regeneration
can be found on the leaflet enclosed with every column.
In the case of separating columns with carrier material based on silica,
only solutions with pH 2 … 7 may be used for regeneration, other-
wise the columns could be damaged.
4.1.2 High-pressure pump
Pulsation dampener
The MF 6.2620.150 Pulsation dampener belongs to the standard ac-
cessories of the 861 Advanced Compact IC; its installation is described
in Section 2.6.2. It is used to reduce interfering pulsation in highly sensi-
tive measurements and also protects the column material against pres-
sure shocks caused by the injection.
Maintenance
To protect the pump against foreign particles we advise you to subject
the eluent to microfiltration (0.45 µ m filter) and siphon the eluent
through the 6.2821.090 Aspirating filter.
In many cases an unstable baseline (pulsation, flow fluctuations) can
be traced to contaminated valves or faulty, leaky piston seals.
Contaminated valves are cleaned by rinsing with water, RBS solution
or acetone (see Section 4.2.6). When the cleaned valves are reinstalled
you must ensure that the flow direction is correct.
The replacement of piston seals is described in Section 4.2.6.
Salt crystals between the piston and the seal are the cause of abrasive
particles, which can enter the eluent. These lead to contaminated
valves, pressure rise and in extreme cases to scratched pistons. It is
thus essential to ensure that no precipitates can appear (see also
Section 4.1.3).
4.1.3 Eluents
Treatment
For the preparation of the eluents only chemicals of a purity degree of
at least "p.a." should be used. For diluting please use only high purity
water.
Fresh eluents should always be microfiltered (0.45
µ m filter) and de-
gassed (with N
2
, He or vacuum). For alkaline eluents and eluents with