What is the typical length of capillary columns?
Most packed columns are 1.5 – 10m in length and have an internal diameter of 2 – 4mm. Capillary columns have an internal diameter of a few tenths of a millimeter. They can be one of two types; wall-coated open tubular (WCOT) or support-coated open tubular (SCOT).
How do you choose a capillary column?
The selection of the proper capillary column for any application should be based on four significant factors: stationary phase, column I.D., film thickness, and column length. The practical effects of these factors on the performance of the column are discussed briefly in this section, in order of importance.
How does a capillary column work?
Capillary columns are gas chromatography (GC) columns that have the stationary phase coating their inner surfaces rather than being packed into the cavity. Capillary GC columns are used to analyze samples for the individual chemical compounds that they contain.
What is the difference between packed column and capillary column?
The main difference between packed column and capillary column is that, in a packed column, the stationary phase is packed into the cavity of the column whereas, in a capillary column, the stationary phase coats the inner surface of the cavity of the column.
What is a plot column?
PLOT columns generally are made by conglomerates of particles that are deposited as a layer inside of the capillary. The layer is porous, meaning that the gas pressure inside the column also will be present between the individual particles.
Why is capillary column longer than packed column?
Due to the fully-packed stationary phase, the pressure inside the column is maintained at a high value. Its length is shorter as compared to the capillary column, but the diameter here can go up to several millimetres. The stationary phase here can be available in both solid and liquid forms.
How many types of columns are there in GC?
Two types of columns are used in gas chromatography: packed columns and capillary columns.
