The invention provides a method for preparing a magnetic hydrophobic modified cationic
polyacrylamide oil-removing flocculating agent and belongs to the technical field of environmental-friendly
water treatment. The method comprises the following steps: dissolving dodecyl
glucoside (or cocoanut
fatty acid diethanolamide), dimethyl diallyl
ammonium chloride,
acrylamide and a
photoinitiator in water, regulating the pH value, introducing
nitrogen and sealing the reactor, performing photopolymerization under a low-
voltage ultraviolet lamp so as to produce lacteous
colloid; and dissolving the
colloid in
ultrapure water, adding magnetic nanometer
iron oxide particles and
ammonium persulfate to stir, washing,
drying,
grinding, and finally obtaining the black powdered oil-removing flocculating agent. According to the method disclosed by the invention, the
polymerization time is short, the
reaction temperature is low, condensation cooling is not needed, and
energy conservation and consumption reduction are realized; due to the introduction of a
hydrophobic monomer, the hydrophilic property of the flocculating agent is reduced, the adsorptive property of oil substances is enhanced, and the demulsification ability of the flocculating agent is enhanced; and due to the introduced magnetic nanometer
iron oxide particles, under the action of an additional
magnetic field, the flocculating agent is high in
settling speed and easy to separate.