Nanofiltration Membrane Materials and Preparation

Nanofiltration (NF) is currently an important branch of membrane technology as it allows the separation of small organic solutes and divalent ions from water. The most commonly applied NF membranes are synthesized either through a process called phase inversion, giving rise to a rather thick (μm-range) membrane, or through interfacial polymerization, creating a thin, selective layer (nm-range). Both synthesis procedures with their respective tuning parameters are extensively discussed in this chapter. The different methods to apply coatings or to modify surfaces are also included. Next to polymeric membranes, the applicability and synthesis conditions of ceramic membranes are also discussed, together with the preparation of hollow fiber membranes. A brief overview of commercial and novel NF membranes, including solvent-resistant nanofiltration (SRNF) membranes, is also provided. To conclude, an outlook about the use, the potential, and the pitfalls of (SR)NF technology is given.