GC015 Instrumentation and columns – Part 1

 

The main components of the gas chromatographers are: carrier gas supply, injection ports or inlets, column (inside an oven), flow controllers, detector and a data system.

The column is the essential part of the technique because it is where the separation occurs. The first columns were the packed columns, metal tubes of 1-2 meters length and 0.2-0.4 cm of inner diameter, packed with inert supports which were coated with the stationary liquid phases. Today, the fused silica columns are of widespread use and are open tubes called capillary columns, due to their small inner diameter (0.1-0.53 mm). The stationary liquid phase is coated on the inner surface of the tube, forming a coating with a thickness of around 0.1-5 µm.

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