The invention discloses a
chitosan-based composite adsorbent capable of synergistically and efficiently removing positive and negative ions of
heavy metals and a preparation method thereof and belongs to the technical field of heavy
metal wastewater treatment. The preparation method of the
chitosan-based composite adsorbent comprises the steps that A,
chitosan powder is dissolved in an
acetic acid solution to form a chitosan mother solution,
ferric sulfate and polyethyleneimine are put into the chitosan mother solution, uniform stirring is performed, and a mixed mother solution is obtained after preliminary crosslinking is performed by using
epoxy chloropropane; B, the mixed mother solution is pumped into a coagulating bath, and composite microspheres are obtained through
precipitation solidification; C, the composite microspheres are taken out and put into asodium
hydroxide water solution, crosslinking is performed by using
epoxy chloropropane to obtain crosslinked microspheres, and the crosslinked microspheres are washed by using
distilled water till the crosslinked microspheres are neutral and then are dehydrated and saved for standby application. The chitosan-based composite adsorbent is simple in preparation, low in cost, stable in structure, superior in performance, can synergistically and efficiently remove the positive and negative ions of
heavy metals and has wide application prospect on the aspect of synergistic control of combined pollutants of heavy
metal positive and negative ions.