The effect of the nature of the carrier gas on the character of the gas chromatographic separation of isomeric mixtures of benzene derivatives

It is shown that chromatographic columns in series containing Silicate-1 (an adsorbent wit molecular sieve effect, showing selectivity toward the para isomers) and the stationary phase 1,2,3-tris (cyano-ethoxy)propane permit the simultaneous separation of multicomponent mixtures of isomers of benzene derivatives. The nature of the carrier gas exert a marked influence on the retention times of certain compounds and on the asymmetry of the corresponding peaks in the chromatogram. With the increase of the molecular weight of the carrier gas in the order of He --> N-2 --> Ar --> CO2, the retention times of the studied compounds are decreased and peak symmetry is increased.