Abstract:The bed expansion and size distribution of ion-exchanger, QMA Spherosil LS, were extensively investigated in a glass column (26 mm I.D.) modified by side ports, and the influences of packed bed height, flow velocity and nature of feedstock were discussed. The results suggested that the characteristics of bed expansion could be well described by Richardson-Zaki Equation. The QMA Spherosil LS had a significant size distribution along the axial direction of column, but a relative uniform density. The classification was changed with the packed bed height and flow velocity. Regardless of the interaction between yeast cell and adsorbent, the classification of the adsorbents varied little in the transition from aqueous buffer to biomass containing feedstock.