Phenomenological study of the bed–wall friction in axially compressed packed chromatographic columns

The properties of column beds prepared with slurries of Kromasil C8 in 12 different solvents, using the same axial compression skid, were investigated. The extent of the consolidation of the column beds, their permeabilities, and the friction shear stress of these beds against the column wall were determined, as well as the column efficiencies (for an unretained tracer). The results of this study illustrate the influence of the wall effect on the consolidation. The permeability of columns consolidated under a constant compression stress was found to increase with increasing bed length. The bed–wall friction shear stress increases rapidly with increasing bed length and varies widely with the nature of the solvent used. No correlation was found between this shear stress and any physico–chemical property of the solvent. The best efficiency was observed for a column consolidated from a slurry in ethanol.