High-performance liquid chromatography of amino acids, peptides and proteins: CXXIV. Physical characterisation of fluidized-bed behaviour of chromatographic packing materials

Abstract

Bed expansion characteristics of several different chromatographic sorbent materials have been studied in liquid-solid fluidized bed systems with different column diameters. The sorbents used were sized below particle diameters ( d p) of 100 μm, and most were non-spherical in shape. The effect of particle shape and size distribution on the bed expansion behaviour and the values of bed expansion index were evaluated in relation to existing empirical correlations of bed voidage and fluid velocity under laminar flow conditions. The effect of fluid properties on the bed behaviour was studied using viscous bovine amniotic fluid as the feed stock. An axial dispersion model was used to compare the liquid mixing behaviour of the fluidized bed system with two different particle sizes of porous silica in 2.24 cm I.D. and 5.0 cm I.D. columns. The results on the bed expansion characteristics with these systems are discussed in terms of the dispersion coefficient, D x and the Peclet number N pe, for these sorbents fluidised under laminar flow conditions.