Separation metod - separation of anlytes in the gaseous phase The compounds are separated on the basis of different migration in the system two phases – stationary and mobile The compound is carried with mobile phase through the stacionary phase in column. Here are individual component with different retention that are succesively eluted from the column with mobile phase. For evaluation of signal detectors are used.
Phases - mobile (liquid, gas) = carrier gas – H 2, N 2, He, Ar must by chemically inert must by chemically inert - stationary ( solid, anchored liquid) – silicone oil Sampling - inject sample through septum - multiway-cock - autosampler sampling volume 30-50 µl or 1-5 µl sampling volume 30-50 µl or 1-5 µl
Columns - packed - metalic (Al, Cu) glass – diameter 6 mm, lenght 3-5 m 3-5 m - capillary – (plastics, glass) – diameter 0,25 mm, lenght 50-100 m lenght 50-100 m Capillary column Capillary column
Detectors - evaluation of analytical signal - thermal conductivity, flame-ionization, electron capture detector, He-detector Thermal conductivity detector Flame ionization detector