The invention discloses a preparation method of a layer-by-layer self-assembled hollow
fiber forward osmosis membrane. The preparation method comprises the steps of: preparing hollow
fiber forward osmosis base film, modifying hollow
fiber ultrafiltration base film, repeating layer-by-layer
assembly of polycation and polyanion
layers, performing interface cross-linking
polymerization for preparinga selective functional layer, conducting moisturizing, and carrying out treatment and storage so as to prepare the layer-by-layer self-assembled hollow fiber
forward osmosis membrane. The surface of the hollow fiber self-support base film which is prepared by using a
phase conversion method is activated firstly, layer-by-layer
assembly of polycation and polyanion is repeated on the surface of thefilm so as to form an functional polarization layer for an
electrolyte solution, and the
polyamide selective layer is prepared through interfacial chemical cross-linking
polymerization. The prepared hollow fiber forward
osmosis membrane has a controllable thickness and an internal polarization layer with a high charge capacity, and the internal
concentration polarization phenomenon can be alleviated effectively during the forward
osmosis process; therefore, the hollow fiber forward
osmosis membrane can simultaneously obtain
high flux and low reverse salt flux, has high
filtration separation efficiency, easy cleaning and a long service life, and can be widely applied to
seawater desalination and concentration and
desalination of brine.