In the present work, the effect of bed expansion and buffer type on the adsorption of amylases from maize malt on Amberlite 410 ion-exchange resin was studied. The hydrodynamic behavior of an expanded bed adsorption column was studied to obtain the optimal conditions of amylases recovery on ion-exchange resin. Residence time distribution showed that HEPT, axial dispersion and the Prandt number increased with bed height, bed voidage and linear velocity. The adsorption capacity of amylases on the resin increased with bed height and the phosphate buffer shows the best recovering of amylases from maize malt on the Amberlite IRA 410 ion-exchange resin. (c) 2006 Elsevier Ltd. All rights reserved.