Grob test mixture, capillary

The following capillary GC tests were performed with the Grob Test Mixture (7 ), listed in "Table IV". It represents a combination of constituents of varickble polarity and reflects quite well the real world of industrial problems. 

In "Figure 5" a compcurison is made between isothermal and temperature programmed capillary GC with equal retention times for the last eluting component of the Grob Test Mixture. In order... 

Fig. 3.9. Gas chromatograms (FID) of test mixtures on AR-glass capillary columns. (1) Grob test mixture on OV-21S. Initial temperature 70°C, programmed at 5°C/min. Peaks Cn = undecane ol = octanol P = 2.6-dimethylphenol s = 2-ethylhexanoic acid al = nonanal A = 2,6-dimelhylaniline am = dicyclohexylamine E,o, E, and E,j = C,q, C, and C,2-acid methyl esters. (2) Nitrophenol test on SE-52. Initial temperature 100°C, programmed at 7°C/min. Peak assignment o, m, p = oriho,meta,para-nilTophenol , 2,4, 2,6 = 2,4-dinitrophenol and 2,6-dinitrophenol. (3) Diamine test on SE-30. Initial temperature 60°C, programmed at 7°C/min. Peaks dh = 1,6-diaminohexane do = 1,8-diaminooctane. Reproduced from [lOS].

The use of dendronized silica as a stationary phase in capillary gas chromatography was pioneered in 2001 by Newkome et al.," who used the triply branched dendrons prepared in solution and immobilized on fused silica inside the capillary column. The dendritic architecture provides unique selectivity in separation of a Grob test mixture of compounds. The same dendron-silica hybrids were used by the authors for solventless capillary microextraction (CME) and preconcentration in chemical analysis. 

For a capillary column, quality is also measured by the use of a standardized test mix, developed by Grob et al. (Figure 6). This mix is intended to provide qualitative information about the stationary phase coating, and in particular activity toward certain solutes. Thus, the mixture contains 2,3-butanediol, -decane, 1-octanol, nonanal, 2,6-dimethylphenol, 2-ethylhexanoic acid, 2,6-dimethylaniline, -dodecane,... 

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