Modification or Fabrication Methods Previously Applied to Produce NF Membranes

3 Modification or Fabrication Methods Previously Applied to Produce NF Membranes 

As discussed, NF process simulation offers some possible process optimization by predicting the membrane-fouling mechanisms and sources of performance deterioration. However, membrane modification and fabrication stiU ranains as one of the most attractive research strategies, offering a complete solution to the drawbacks associated with NF membrane applications. Development of new manbrane materials with special features such as antifouling, biocompatibility, and functionality has become the current trend in NF research. 

There are several methods that have been previously employed to produce NF membranes with targeted function. One of the most used methods to produce NF membranes is interfacial polymerization (Gohil and Ray 2009 Wang et al. 2011b), which is the main method used commercially to produce thin-fitm composite membrane (Rahimpour et al. 2010). In this method, a porous substrate or membrane support is normally required before the formation of a dense layer. However, there are several complexities for the interfacial polymerization technique, such as the 

FIG U RE 4.1 Stability test of the composite membrane formed by interfacial polymerization of 1,3-PDA with TMC using PES membrane as substrate. (Reprinted with permission from Rahimpour, A. et al. Appl. Surf. ScL, 256,1657-1663, 2010.) 

FIGURE 4.2 Membrane surface atomic force microscopy images (a) PES pure membrane and (b) poly(piperazine-amide) composite membrane. (Reprinted with permission from Jahanshahi, M. et al, Desalination 257, 129-136, 2010.) 

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