Nanofiltration and Preparation of Polymerized Composite Nanofiltration Membrane

Nanofiltration is a new separation technique between reverse osmosis and ultrafiltration. The advantage of nanofiltration is that the molecular weight cut-off to organics is about several hundred and that the rejection coefficient to ions of different valence is quite different. It has been widely used in many fields. The mass transfer mechanisms of nanofiltration technology, such as Space-chareged Pore Model, TMS Model and Hybrid Model, are described in the paper. The advantages and shortcomings of the preparation methods of the nanofiltration membranes are introduced in detail, especially the interfacial polymerization ,including material, affecting factors and the characteristics. It is pointed out that the directions of future research are process optimization, the development of new nanofiltration membrane and intergation technology.