This presentation will describe how layer by layer (LBL) technology can be used to prepare ultrathin films suitable for use within membrane systems. A simple polyethylene glycol film constructed using a LBL approach can be used to reduce biofouling when added to standard reverse osmosis membranes. Alternatively LBL structures can be used to replace the polyamide structure completely with an alternate chemistry. We have investigated combinations of the polyanions polystyrene sulfonate (PSS) or sulfonated polysulfone with the polycation poly(allylamine)hydrochloride for this purpose. The resulting membranes have achieved NaCl rejections of over 97% by crosslinking with glutaraldehyde. Importantly, these structures are far more resilient to attack by chlorine, meaning that they have strong potential for systems where biofouling is a concern. We have also used the same approach to secure the carbonic anhydrase enzyme to the surface of a porous hollow fibre membrane, for use within a membrane contactor. Immobilisation of the membrane on the surface of the hollow fibre leads to enhanced mass transfer and reduced pore wetting in carbon capture applications.
Level 0, between bld. 4 and 5
14:30 - 15:00