THE MAGNETICALLY STABILIZED FLUIDIZED-BED BIOREACTOR - A TOOL FOR IMPROVED MASS-TRANSFER IN IMMOBILIZED ENZYME-SYSTEMS

Studies were carried out using novel magnetic carrier particles in a m agnetically stabilized fluidized bed (MSFB) to determine the degree of liquid phase mass transfer enhancement achievable over a range of mag netic field strengths. The carrier particles, beads of K-carrageenan i ncorporating magnetite, ranging in size from 0.25 to 1 mm are used for enzyme immobilization. Results using a 113 mm diameter column showed that a more than five-fold increase in liquid velocity could be achiev ed when a current of 40 A was applied to a single magnetic coil. The ' 'escape'' velocity of the particles from the bed was found to be propo rtional to the magnetic field intensity squared. The effect was furthe r increased (almost doubled) by inserting a steel rod into the centre of the bed.