17
Intended use
Precleaning of a sample
Basics
The precleaning of a sample is used in chromatography, for
example in the following cases:
Preseparation or separation of heavily retarding substances
Precleaning samples, alternating and time-delayed on differ-
ent precolumns
Optimization of analysis times
Fig. 16
Application example right: Precleaning alternating on
two precolumns and analyze all substances from both
precolumns.
The sample is precleaned on precolumn 1 and the weak retard-
ing substances are flushed directly on the analytical column and
separated there.
After switching over the valves, precolumn 1 is cleaned and the
sample is precleaned on precolumn 2 and flushed to the analyti-
cal column to be separated there.
Note:
Make sure there is no pressure when switching
between the columns so that the columns are not
damaged.
Injection
on precolumn
1
2
3
4
5
6
Injection
Precolumn
Detector
Column
