Surface treatments and functionalization of metal‐ceramic membranes for improved enzyme immobilization performance

Abstract

AbstractBACKGROUNDEnzyme immobilization in porous membranes often improves enzyme performance. This work reports the preparation and characterization of robust and scalable asymmetric metal‐ceramic microfiltration membrane. The surface of the porous metal‐ceramic membrane was treated by impregnation with a ceramic oxide for enzyme adsorption and corrosion protection. Finally, enzyme immobilization in the support was investigated.RESULTSThe bilayer membrane was successfully fabricated by combining a ceramic microfiltration layer with a metal support by tape casting, lamination and co‐sintering. A pore size in the ceramic microfiltration layer of 0.4 μm resulted in high water permeability (12 000 L/(m2 h bar)). Two different surface treatments were compared: heat treatment and yttrium(III) oxide (Y2O3) impregnation. Corrosion stability tests under enzyme‐relevant conditions gave no detectable chemical or structural changes. Alcohol dehydrogenase (EC 1.1.1.1) was immobilized in the membrane by physical adsorption and by two covalent immobilization methods. Covalent immobilization significantly improved enzyme loading, activity, and recyclability. Membrane reuse by heat treatment removed fouling, but decreased immobilization performance.CONCLUSIONThe improved microstructure obtained by Y2O3‐impregnation had a significant effect on enzyme loading yield and activity. This indicates the potential of this surface modification method and of these metal‐supported ceramic membranes in enzyme immobilization. Covalent immobilization was superior. © 2019 Society of Chemical Industry