Gas Chromatography - GC Columns > The Capillary or Open Tubular Column > Static Coating > Page 31

 

Irrespective of the coating method, column stability depends on the stability of the stationary phase film which depends on the constant nature of the surface tension forces that hold it to the column wall. These surface tension forces can be reduced with an increase in temperature or by the solutes passing through the column.

 

Courtesy of Supelco, Inc.

 

1/ Dichlorodifluoromethane 18/ Bromodichloromethane
2/ Chloromethane 19/ 2-Chloroethyl vinyl ether
3/ Vinyl chloride 20/ cis-1,3-Dichloropropene
4/ Bromomethane 21/ Toluene
5/ 1,1-Dichloroethylene 22/ trans-1,3-Dichloropropene
6/ Methylene chloride 23/ 1-Chloro-2-bromopropane
7/ trans-1,2-Dichloroethylene 24/ 1,1,2-Trichloroethane
8/ 1,1-Dichloroethane 25/ Tetrachloroethylene
9/ cis-1,2-Dichloroethylene 26/ Dibromochloromethane
10/ Chloroform 27/ Chlorobenzene
11/ Bromochloromethane 28/ Ethylbenzene
12/ 1,1,1-Trichloroethane 29/ Bromoform
13/ Carbon Tetrachloride 30/ 1,4-Dichlorobutane
14/ Benzene 31/ 1,1,2,2-Tetrachloroethane
15/ 1,2-Dichloroethane 32/ 1,3-Dichlorobenzene
16/ Trichloroethylene 33/ 1,4-Dichorobenzene
17/ 1,2-Dichloropropane 34/ 1,2-Dichlorobenzene

 

Figure 18. The Separation of Volatile Priority Pollutants

As a consequence, the film can suddenly break up. Thus, it would be highly desirable if the stationary phase was bonded to the column walls or polymerized in situ. Such coatings are called immobilized stationary phases and can not be removed by solvent washing.