Investigation of macroporous carrageenan beads for chromatographic separation

Due to the presence of intraparticle convection which increases intraparticle mass transfer, macroporous beads greatly improve the performance of chromatographic separations, catalyst reactions and cell immobilization. In the research outlined in this thesis, a natural polysaccharide, carrageenan, was employed as a column packing material to investigate the use of macroporous beads for enhanced chromatographic separation. The investigation provided new insight to understanding the effects of intraparticle convection on intraparticle mass transfer and its relationship to chromatographic separation.;Conventional carrageenan beads were prepared by an emulsion method and crosslinked by epichlorohydrin. The beads showed good stability in solutions of varying pH. However, the size and the protein elution volume of the crosslinked hydrogel beads were sensitive to ionic strength, especially a gelling ion, potassium. The bead size increased at low ionic strength. Potassium ions were more effective in decreasing the bead size than sodium ions due to the formation of gels. The elution volume of non-adsorbed proteins in a carrageenan column decreased with a decrease in KCl due to a reduced pore size in the beads. Overall, protein separation by a carrageenan column was slightly better than that of a Sepharose column.;Crosslinked carrageenan-gelatin beads were prepared by a two-step emulsion method. Toluene was used as a pore forming agent. The bead porosity and the pore structure were dictated by the toluene content in the first emulsion. Connected channels with a high bead surface area were found with a high toluene loading content in the first emulsion (i.e. ;Aggregated carrageenan beads with a low degree of aggregation were successfully employed for chromatographic separation. The beads were produced in a fluidized bed by aggregating small subsidiary carrageenan beads. Intraparticle convection occurred in aggregated beads at reduced velocities as low as 30. This effectively decreased the reduced plate height of the aggregated beads in gel filtration. At high flow rates, an even greater decrease in reduced plated height was observed with aggregated beads. The intraparticle mass transfer in aggregated beads was greatly improved by better intraparticle convection at high flow rates. The protein separation behaviour of small subsidiary beads in the aggregates more closely resembled that of conventional beads of the same size as the former with better intraparticle convection.;The Knox equation was modified to incorporate intraparticle convective mass transfer for predicting the reduced plated height. The ratio, (1...