Efficiency for unretained solutes in packed column supercritical fluid chromatography. I. Theory for isothermal conditions and correction factors for carbon dioxide.
A general theory for efficiency of nonuniform columns with compressible mobile phase fluids is applied to the elution of an unretained solute in packed-column supercritical fluid chromatography (pSFC). The theoretical apparent plate height under isothermal conditions is given by the Knox equation multiplied by a compressibility correction factor f1, which is equal to the ratio of the temporal-to-spatial average densities of the mobile phase. If isothermal conditions are maintained, large pressure drops in pSFC should not result in excessive efficiency losses for elution of unretained solutes.
Poe
Donald P
DP
Department of Chemistry, University of Minnesota Duluth, 10 University Drive, Duluth, MN 55812, USA. dpoe@d.umn.edu
D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D008956:Models, Chemical