Packed Columns
Packed columns have been used for the last 50 years in all types of gas chromatography analysis. Today, packed columns are still used because of the wide range of packings available and their high column loading capacity. These aspects make packed columns quite versatile for a wide range of applications, which capillary columns do not address. The tubes used in packed columns are usually glass, stainless steel, and to a lesser extent, copper nickel and Teflon, with diameters of, 1/4" and 1/8" OD and 2, 3 and 4 mm ID. Columns packed in glass tubes are inert, but are very fragile and break very easily, while columns made of metal tubes are strong and flexible, but need to be deactivated before they can be used for active compound analysis.