The invention provides a preparation method of a
chitosan and
polyvinyl alcohol mixed film and the application of the
chitosan and
polyvinyl alcohol mixed film to the aspect of heavy
metal ion separation and removal in water. The
chitosan and
polyvinyl alcohol mixed film is formed by blending the chitosan and the polyvinyl
alcohol, so the chitosan and polyvinyl
alcohol mixed film is enabled to have excellent adsorption and
chelation abilities of a chitosan film, and meanwhile, the
mechanical strength of the chitosan film is greatly enhanced and the service life of the chitosan film is greatly prolonged; and the adsorption and
chelation abilities synergistically act with an interception effect of the chitosan and polyvinyl
alcohol mixed film, so heavy
metal ions can be effectively removed from the water. Compared with a method for removing the heavy
metal ions from a solution in the prior art, a method for removing the heavy metal ions from the water by using the chitosan and polyvinyl alcohol mixed film prepared by adopting the preparation method can overcome the disadvantages that the heavy metal ions cannot be completely removed and poisonous
sludge or waste is produced by using ordinary inorganic or organic adsorbent,
electrocoagulation, and the like, and has the advantages of efficient removal of the heavy metal ions, low
energy consumption, low cost, no secondary
pollution, convenience in operation and the like.