Integration of bioconversion and continuous product separation by means of countercurrent adsorption

Selective product removal from the reaction zone by means of adsorption is advantageous in case of unfavourable thermodynamic equilibria as can be encountered for enzymatic conversions. The application of a multi-stage fluid bed contactor as a continuous device for adsorptive bioconversion is investigated as a possible solution. In this reactor-adsorber, two solid flows (adsorbent and immobilized biocatalyst) can be controlled independently. As a first step in the process design a mathematical model describing the steady state performance of the reactor is developed. The design and construction of a laboratory scale multi-stage fluid bed reactor-adsorber is illustrated for the reversible first order glucose-fructose isomerization with a zeolitic adsorbent as model system. This proved the reactor-adsorber to be an useful tool in the design of (bio-)conversion processes.