Production and characterization of piezo-electric membranes

It is shown that it is possible to impart piezo-electric properties to polyvinylidene fluoride (PVDF) membranes. This was achieved by “poling” the membranes in an intense electric field. Out of the plane surface displacements were produced when AC signals were applied to the membrane. Flux and separation performance measurements performed in a cross flow membrane module demonstrated that piezoelectric induced vibrations out of the plane of the membrane (i.e. in the direction of the flux) increased the flux by an order of magnitude and delayed membrane fouling. The relative antifouling effect of piezoelectric induced vibration was enhanced with increasing cross flow velocity.

Research highlights
► PVDF membranes were electrically “poled” to render them piezoelectric
► These piezoelectric membranes could be set into vibration, normal to the plane of the membrane, by applying electrical signals.
► Such vibrating membranes were dramatically more resistant to fouling when used in a cross-flow module.