Pervaporation separation of water/alcohol mixtures using composite membranes based on polyelectrolyte multilayer assemblies

摘要: Abstract Composite pervaporation membranes composed of an asymmetric polyamide-6 membrane and ultrathin self-assembled polyelectrolyte separating layer are described. The supporting was prepared from both unmodified a comb-like polymer with carboxyl terminated side chains. A high end group concentration found to be advantageous for sufficient adhesion the multilayer systems on supports. Up 20 layers were deposited onto surface by dipping in aqueous solutions containing oppositely charged polyelectrolytes. polyanions used poly(acrylic acid), poly(styrene sulfonic acid) alginic acid. polycations poly(diallyldimethylammoniumchloride), chitosan poly(ethylenimine). Performance these depends strongly number type In general, modified two weak polyelectrolytes charge density gave best separation properties while those strong low led poorer properties. However, highest factor (≥10,000) water/2-propanol mixture (12/88 w/w) at permeate flux 300 g/m 2 h obtained six double consisting poly(ethylenimine) These composite stable over operating period least 400 h.