Metrohm 844 UV/VIS Compact IC - Manual (Page 89)

4.1 Practical notes on ion chromatography
844 UV/VIS Compact IC / Gebrauchsanweisung 8.844.1051
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4 Notes - Maintenance
- Faults
4.1 Practical notes on ion chromatography
4.1.1 Separating columns
Separation efficiency
The attainable quality of analyses with the 844 UV/VIS Compact IC
depends to a large extent on the separation efficiency of the column
used. When purchasing an IC column you should ensure that the
separation efficiency suffices for the analysis problems at hand.
Ascertain the characteristic data of the IC column on the standard
chromatogram enclosed with the column such as capacity factors,
selectivity, plate number and resolution and check these data with your
own measurements. If any difficulties arise, you should always first
check the quality of the column by recording a standard
chromatogram.
Detailed information about the separating columns available from Me-
trohm can be found in the data sheet accompanying your separating
column, in the Metrohm IC Column Catalog, which is available from
your local Metrohm agency, or on the Internet under http://www.met-
rohm.com in the ion chromatography product sector. Information about
special IC applications can be found in the relevant "Application
Bulletins" or "Application Notes"; these are available on the Internet
under http://www.metrohm.com in the applications sector, or can be
requested free of charge from your local Metrohm agency.
Protection
To protect the column against foreign particles which could have an
adverse influence on the separation efficiency, we advise you to subject
both the eluents and all samples to microfiltration (0.45 μm filter) and
to siphon the eluent through the 6.2821.090 Aspirating Filter.
In order to avoid contamination by particles it is advisable to mount an
in-line filter between the pump and injection valve. In the 844 UV/VIS
Compact IC a 6.2821.120 PEEK filter unit / 6.2620.180 Filter unit
Steel is already mounted (see Section 2.3.5 / 2.3.6).
The use of readily interchangeable precolumns serves to protect the
actual separating columns and increase their service life appreciably.
The precolumn that is suitable for your separating column can be found
in the Metrohm IC Column Catalog which is available from your local
Metrohm agency, the data sheet accompanying your separating co-
lumn, the product information about separating columns that can be
found under http://www.metrohm.com , ion chromatography products,
or let your agency advise you directly.