Coating static, capillary columns

Instrumentation. Preliminary gas chromatographic analyses were carried out on a Perkin-Elmer 900 gas chromatograph equipped with a flame ionization detector and on a Hewlett-Packard 5730A gas chromatograph equipped with flame ionization and electron-capture detectors. The columns used were 180 cm x 2 mm ID glass columns packed with 3% SL-2100 (a methyl silicone fluid) on 80/100 mesh Supelcoport we also used 25 m X 0.25 mm ID glass capillary columns statically coated (7) with SE-52. 

Glass Capillary Gas Chromatography. For the quantitative analysis of the PAH a Varian 3700 gas chromatograph equipped, with a flame-ionization detector and coupled with a data system of Spectra Physics was used. The glass capillary columns statically coated with different stationary phases (OV 101, "SE 30 , SE 52,... 

Open tubular columns can be coated internally with the appropriate stationary phase dissolved in a suitable solvent, or, alternatively, with monomeric materials that are subsequently polymerized to form a relatively rigid polymer film on the column walls. There are two basic methods for depositing the stationary phase as a surface film on a capillary column, dynamic coating and static coating, the latter being the most commonly used. 

The desired IL monomers are mixed with a free-radical initiator (azobisiso-butyronitrile, AIBN) in dichloromethane and coated onto the wall of the capillary column using the static coating method. The capillary is then sealed at both ends and heated to initiate polymerization. Finally, the capillary is unsealed and placed in a gas chromatograph and subsequently conditioned to remove any excess AIBN that did not completely decompose or react. 

Coating of capillary column using static coating method... 

The columns used were 20 m long, 300 pm ID. and were pretreated with colloidal silicic acid to stabilize the film of stationary phase. The columns were coated with 0.15% solution of the stationary phase in chloroform using the static method of coating (the different methods of coating capillary columns will be described later). Prior to use, each column was conditioned at 175°C in a stream of hydrogen. The... 

Factors Controlling Selectivity Open Tubular Columns Dynamic Coating Static Coating Column Regeneration Capillary Column Design and Choice Stationary Phases for the GC Separation of Chiral Substances Synopsis References Chapter 6... 

Preparation of high efficiency fused-silica capillary columns coated with graphitized carbon black impregnated with liquid phases was proposed by Bruner and co-workers [23, 24]. This method is a modification of that described by Xu and Vermeulen [25] (free release static coating) for the preparation of glass capillary columns. 

Preparation of the columns is based on a two-step procedure, namely 1) preparation of a slurry where the adsorbent (graphitized carbon black) and the liquid phase (for instance, SP-1000) are mixed together in a suitable solvent and sonicated 2) coating of the capillary columns by means of a static method using the prepared slurry. 

Static Coating of Capillary Columns 3.9.23 CapUlaiy Cages... 

J.Bouche and M.Verzele, A static coating procedure for glass capillary columns, J. Gas Chromatogr., 6 (1968) 501-505. 

The column is the most important part of the system, as its function is to encourage repetitive partitioning of each solute molecule between the gas and the liquid or solid phase. Packed columns are commonly used with the polymer or blend to be analysed coated on to a non-reactive substrate (Chromasorb W) which is then packed into the stainless-steel GC column. More recently capillary columns have been employed. Here the polymer is dynamically or statically coated as a uniform film on to the walls of the fused silica capillary. Inverse gas chromatography is a very flexible analytical technique however, full commercialisation of the technique has yet to be realised. 

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