Gas chromatographic separations of alkanes of urea inclusion compounds with n-alkanes as stationary phases

✍ Scribed by K. Mařík; E. Smolková

• Publisher: Elsevier Science
• Year: 1974
• Tongue: English
• Weight: 726 KB
• Volume: 91
• Category: Article
• ISSN: 1873-3778
• DOI: 10.1016/s0021-9673(01)97909-9

✦ Synopsis

Urea adducts with n-octane, n-decane, n-dodecane, n-tetradecane and nhexadecane have been studied as stationary phases in gas chromatography. With all the adducts examined, selective sorption of n-alkanes and of branched alkanes with a single methyl group in the side-chain was found. This sorption is caused by the presence of hexagonal channels with a diameter of 5 A in the adduct inclusion structure. All factors that increase the dissociation, i.e. temperature or the content of the guest molecules, increase the adduct selectivity. On the other hand, all factors that suppress the dissociation, i.e. the chain length of the guest molecules and the vapour pressure of the guest molecules, decrease the selectivity. The sorption properties of the adducts were utilized for the separation of model alkane mixtures.