The invention provides a method for preparing a heavy
metal adsorbent by using modified
bagasse. The method comprises the following steps of: a. stoving or
drying the
bagasse, and then crushing and sieving so as to obtain
bagasse powder; b. immersing the bagasse
powder in a
potassium permanganate solution with the concentration of (0.8 to 1.2) g / L, uniformly stirring, importing
nitrogen and removing
oxygen, and reacting for 40 to 80 minutes at the temperature of 40 DEG C to 70 DEG C; d. then adding
acrylonitrile and N, N,-methylenediacrylamide, importing
nitrogen and removing
oxygen again, and reacting for 40 to 80 minutes at the temperature of 40 DEG C to 70 DEG C; e. in the step d, adding a
hydroquinone solution with the concentration of (8 to 12) mg / L 2 to 5 minutes before the reaction is finished; and f. washing a reactant, draining, filtering and
drying so as to obtain a heavy
metal adsorbent crude product, wherein the addition amounts of the
acrylonitrile, the N, N,-methylenediacrylamide and the
hydroquinone solution respectively account for 0.1% to 0.3%, 1% to 3%, 0.05% to 0.1% of the weight of the bagasse
powder. The adsorbent prepared with the method has the advantages of simple using method, low cost and excellent
adsorption effect.