## Abstract Although the mobile phase is generally considered to be incompressible in liquid chromatography, the local pressure appears to have a significant effect upon solute retention. In this investigation, laser fluorescence detection was utilized to measure solute retention directly along a r
Direct examination of separation processes in liquid chromatography: Effect of temperature and pressure on solute retention
β Scribed by Victoria L. McGuffin; Christine E. Evans; Shu-Hui Chen
- Publisher
- John Wiley and Sons
- Year
- 1993
- Tongue
- English
- Weight
- 680 KB
- Volume
- 5
- Category
- Article
- ISSN
- 1040-7685
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
In this study, retention processes in reversedβphase liquid chromatography were examined in situ along an optically transparent column by means of laserβinduced fluorescence. Using a homologous series of derivatized fatty acids as model solutes, the capacity factors were systematically measured as a function of temperature in the range from 10 to 60Β°C and pressure in the range from 980 to 4,430 psi. A phase transition was observed for the octadecylsilica stationary phase as temperature was decreased and as pressure was increased. From evaluation of its thermodynamic properties during this phase transition, the stationary phase appears to be more similar to a randomly oriented alkane solvent than a highly ordered system such as a phospholipid membrane. Because this phase transition occurs within the range of routine operating conditions in liquid chromatography, it has important implications for both fundamental and practical applications.
π SIMILAR VOLUMES
Solid-Liquid Mass Transfer in Cocurrent Two-Phase Flow Through Packed Beds," Ind. Eng. C h e m . , Process Des. D e n , 17(3), 362 (1978). Sylvester, N. D., and P. Pitayagusam, "Mass Transfer for Two-Phase Cocurrent Downflow in a Packed-Bed," Ind. Eng. C h e m . , Process Des. D e u . , 14,421 (1975
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