what is the anti-pollution performance of ge organic solvent resistant nanofiltration membrane?
nanofiltration membrane can be used for selective separation because its molecular weight cut-off is between reverse osmosis and ultrafiltration membrane, and it has been widely concerned in municipal and industrial water treatment fields. However, there are organic and inorganic pollution and microbial pollution in the practical application of nanofiltration membrane, which not only adversely affects the sustained and stable operation of nanofiltration membrane system, but also increases the actual operation cost. Therefore, it is very important to prepare nanofiltration membrane with strong anti-pollution at the membrane material end.
At present, the research of anti-pollution nanofiltration membrane can be divided into two aspects: anti-pollution monomer and anti-pollution modification of membrane surface. The anti-pollution modification of nanofiltration membrane surface is to improve the anti-pollution performance of membrane by changing the hydrophilicity, charge, roughness and functional groups of membrane surface.
surface physical coating usually refers to coating hydrophilic polymers containing hydroxyl and carboxyl groups on the surface of nanofiltration membrane to modify the membrane surface. The high hydrophilicity of membrane surface can prevent the adsorption of hydrophobic pollutants, reduce the roughness of membrane surface and improve the anti-pollution performance of membrane. Antibacterial polymers include polyamino acids and polymers containing tertiary ammonium and quaternary ammonium groups. The surface grafting modification of nanofiltration membrane mainly uses zwitterions to graft onto the surface of polyamide separation layer, and improves the anti-pollution ability of the membrane by improving the hydrophilicity of the membrane surface.