The invention relates to a preparation method for forming
magnetite nanoparticles in a
cellulose acetate membrane. The preparation method comprises: preparing a
cellulose acetate membrane; adding 8-hydroxyquinoline, and
casting the solution on a glass plate base material through a
casting knife; washing the prepared membrane, and soaking in water;
drying the film; violently mixing a
polyvinyl alcohol polymer, and dissolving in water to obtain a uniform solution; adding
ferric chloride, and dropwisely adding
sodium hydroxide into the
mixed solution; carrying out ultrasonic treatment on the solution through an ultrasonic instrument oscillator, and breaking the material aggregate; and immersing the
cellulose acetate membrane into the nanometer
composite material solution, discharging the excessive solution, and
drying to obtain the
cellulose acetate membrane. According to the invention, the membrane prepared by adopting the preparation method is improved in
ion removal performance, improved in
membrane surface hydrophilicity, good in adsorption performance and
mechanical integrity, and capable of being repeatedly used.