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Low aspect ratio packed capillary columns in supercritical fluid chromatography

✍ Scribed by Wenbao Li; Dongjin Pyo; Yanjian Wan; Elena Ibaňez; Abdul Malik; Milton L. Lee

Publisher
John Wiley and Sons
Year
1996
Tongue
English
Weight
1004 KB
Volume
8
Category
Article
ISSN
1040-7685

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✦ Synopsis

Packed capillary columns with low aspect ratios (column diameter/particle diameter, d,/d,) can be prepared by selecting the appropriate combinations of column and particle diameters. They provide lower pressure drops and higher permeabilities than columns with higher ratios. Therefore, longer columns can be used to generate higher column efficiencies. In this study, the chromatographic behavior of low aspect ratio packed capillary columns was evaluated using supercritical fluid chromatography. The results of this investigation indicate that low aspect ratio packed capillary columns have better mass transfer properties and give lower reduced plate heights than those with higher ratios. A reduced plate height of as low as 1.3 was obtained for columns with aspect ratio of 5. Large diameter columns packed with large particles provide greater permeabilities and sample capacities than small diameter columns packed with small particles. Spherical particles resulted in significantly lower reduced plate heights than irregular particles. The advantages of low aspect ratio packed capillary columns are illustrated from practical SFC separations.

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