Investigation on Preparation and Performance of Self-Assembly Nanofiltration Based on the Coordination

Abstract

Layer-by-layer self-assembly technology has been widely used and developed recently. However, most assembly was directly carried out using polyamions and polycations which is simply based on electrostatic force. In this work, a coordination multilayer with PS ultrafiltration (UF) membrane as substrate was explored by the alternate deposition of a transition-metal-containing polyelectrolyte and a ligand-containing polymer via the formation of complexes. Desalination experiments showed that for single salt solution filtration, the prepared metal-ligand-coordinated multilayer membrane has a 85% rejection of Na2SO4 and a solution flux of 60 L/m2h at 1.0MPa, while the rejection of NaCl was only 20% and the solution flux was about 85 L/m2h at the same pressure. Continuous test indicated that the performance of the membrane is basically unchanged during the two weeks, so the prepared membrane has excellent stability and resistance to swelling.