The invention discloses a preparation method of a crosslinking
nanofiltration membrane. The method comprises the steps of completely dissolving phenolic resin and tetraethenyl triamine in a certain
mass ratio through a medium, wherein the
mass ratio of phenolic resin to tetraethenyl triamine is (2-3):(5-6), and the
mass ratio of phenolic resin to the medium is (8-10):(2-3); uniformly agitating to obtain a settled solution, wherein the medium is prepared from
polyethylene glycol and a surface
active agent OP-10 in the
mass ratio of (4-8):(2-3); removing bubbles; adding a crosslinking agent, namely, a
formaldehyde solution; continuously agitating; preserving heat for 1 to 24 hours at the temperature of 60 to 80 DEG C in a
drying tank; agitating for 2 to 4 minutes at the rotating speed of 1,000 to 3,000r / min to obtain a
casting membrane solution;
coating a
glass sheet with the generated
casting membrane solution by a film
casting method;
drying under a vacuum condition at the temperature of 60 to 80 DEG C; soaking for 2 to 4 hours through a
diethyl ether solution to remove the medium, namely,
polyethylene glycol and the surface
active agent OP-10; washing with
alcohol and
distilled water for a plurality of times; and then
drying to obtain the crosslinking
nanofiltration membrane. The method is performed under mild preparation conditions, does not have strict requirements, is convenient to operate, enables simple forming, and meets the demand on mass production; the prepared
nanofiltration membrane is of a
symmetric structure, and is uniform in pore size distribution, adjustable in pore size, and outstanding in
repeatability.