Recent Developments in Fouling Minimization of Membranes Modifed with Silver Nanoparticles

When incorporated in membranes, Ag0 nanoparticles are effective antifouling and antibacterial agents, arising from the presence of Ag+ ions either in solution or adsorbed onto nanoparticles. A variety of organic and inorganic composite membranes involving silver show good results. Long-term prevention of biofouling by such membranes does not seem to have been satisfactorily obtained yet. Ways of counteracting silver loss from the membranes need to be sought. Recovery by the reduction of soluble silver ions to elemental silver at regular intervals may be one possible method, but this is not feasible when the silver ends up in the product water. However, the regenerating and recycling of Ag+ ions could be especially relevant in the case of organophilic pervaporation, where the aqueous phase is retained and does not pass through the membrane. There is a potential for creating a practical long-lasting antifouling system for that proces.