Elster GmbH
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EnCal 3000 Quad– Hardware Manual
22/06/2017
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1.1.1
Column
A GC column is a relatively long spiral of tubing with very small internal diameter. Typical dimensions of the
used columns in the Encal3000 Quad are a length of several meters and internal diameters of <0.1 mm.
They are made of inert materials like fused silica and stainless steel. Every GC column has a so-called
stationary phase inside, which acts as an absorption layer for the gas molecules flowing through the column.
Fig. 1-2 Different types of gas chromatographic columns
Various configurations are used depending on the components to measure:
Wall coated open tubular column: the stationary phase is a thin liquid layer coated on the
inner wall of the column (for example type 5CB)
Packed column: the stationary phase is coated on a packing, which is equally distributed
throughout the column (for example type HSA)
Support coated open tubular column: the stationary phase is a coated packing, which itself is
coated on the inner wall of the column (for example type M5S / molesieve)
Porous layer open tubular column: the stationary phase is a porous layer on the inner wall of
the column (for example type PPU)
