High-temperature separation with polymer-coated fiber in packed capillary gas chromatography

Abstract

High-temperature gas chromatographic separation of several synthetic polymer mixtures with Dexsil-coated fiber-packed columns was studied. A bundle of heat-resistant filaments, Zylon, was longitudinally packed into a short metal capillary, followed by the conventional coating process with Dexsil 300 material. Prior to the packing process the metal capillary was deactivated by the formation of a silica layer. The typical size of the resulting column was 0.3-mm i.d., 0.5-mm o.d., 1-m length, and packed with about 170 filaments of the Dexsil-coated Zylon. The column temperature could be elevated up to 450 degrees C owing to the good thermal stability of the fiber, Dexsil coating, and metal capillary; furthermore, this allowed the separation of low-volatile compounds to be studied.

High-Temperature Separations on a Polymer-Coated Fibrous Stationary Phase in Microcolumn Liquid Chromatography

“…[23][24][25][26] First, a fused-silica capillary of 0.32 mm i.d., 1.0 m length packed with 332 of Zylon filaments was connected to a pressure-proof vessel containing 10 mL of acetone, and washed with a solvent pumped by N2 gas at a pressure of 500 kPa. After the same volumes of the following solvents, water, acetone and chloroform, were pumped in a similar manner, the capillary was allowed to dry by using N2 gas flow at room temperature for about 2 h. Second, the capillary was subjected to heating in a GC oven with the flow of N2 gas.…”

“…[15][16][17][18][19][20][21][22] These fibrous materials were also employed as a stationary phase in GC, because of their excellent thermal stability over the temperature range typically used in most of GC separations. [23][24][25][26][27] Coated with typical polysiloxane-based materials onto the surface of the fibrous materials, the retentivity was significantly improved, and also the selectivity could be designed on the basis of the type of polymeric coatings. [24][25][26][27] In terms of the fibrous stationary phases in micro-LC, Kiso et al have reported examples of the separation of alcohols and polycyclic aromatic hydrocarbons (PAHs) on capillary columns packed with fibrous cellulose acetate.…”

“…[23][24][25][26][27] Coated with typical polysiloxane-based materials onto the surface of the fibrous materials, the retentivity was significantly improved, and also the selectivity could be designed on the basis of the type of polymeric coatings. [24][25][26][27] In terms of the fibrous stationary phases in micro-LC, Kiso et al have reported examples of the separation of alcohols and polycyclic aromatic hydrocarbons (PAHs) on capillary columns packed with fibrous cellulose acetate. 28,29 Marcus et al applied so-called capillary-channeled polymer (C-CP) fibers as stationary phases in LC.…”

Rapid Temperature-Programmed Separation and Retention Prediction on a Novel Packed-Capillary Column in Gas Chromatography

“…Packed-capillary columns were prepared in a conventional manner, as described previously, 11 except for the use of a stainless-steel capillary of 1.0 mm i.d., 1.27 mm o.d., 1.0 m length and a packing material having a relatively smaller particle diameter, as described below, where with a careful packing the resulting column efficiency per unit length was almost the same as that of the typical conventional particle-packed columns. A pair of stainless-steel capillaries of 0.3 mm i.d., 0.52 mm o.d., 0.5 m length were attached to the inlet and outlet of the packed-capillary column, thus allowing easy installation of the packed-capillary column to a conventional GC injector designed for capillary column connection.…”

“…[8][9][10] Packed with a bundle of filaments having a polymeric coating material thereon, a parallel alignment of these filaments was formed in a short capillary, and the resulting polymer-coated fiber-packed columns showed a satisfactory separation performance with a fast temperature-programming rate in GC. 11,12 It has been demonstrated that the use of a narrower capillary allows these columns to be operated at a fast temperature-programming rate, as compared with conventional particle-packed columns. Downsizing of the packed column also permits the use of the resulting miniaturized packed column in a modern capillary GC system without any special modification to the instruments, although the compatibility of the packed column to the temperature-programmed operation should be considered as typically reported in several publications dealing with the theoretical prediction of the retention time for separation with temperature programming.…”