Preparation method of aluminum hydroxide film

The invention discloses a preparation and using method of an aluminum hydroxide film, which is based on sodium aluminate and used for adsorbing Cr (VI). The preparation method comprises the following steps of: firstly, adding concentrated HCl to a sodium aluminate solution to form stable aluminum hydroxide sol particle precipitates, and hydrolyzing for a certain time under a certain temperature; then, adding peptizing agent for peptizing, so that the soil partciels are uniformly dispersed; and adding coalescing agent polyvinyl alcohol (PVA), ageing for a certain time to form stable gel; and coating to obtain the aluminum hydroxide film. The preparation method of the aluminum hydroxide film has the advantages of being cheap in material, gentle in condition, simple in process and the like. The prepared aluminum hydroxide film has good adsorption performances to highly toxic pollutants Cr (VI) in water, and especially has remarkable advantages on separating, regenerating and recycling adsorbents.