▎ 摘　　要

NOVELTY - A self-assembled oxidized graphene/quaternized chitosan positively charged composite nanofiltration membrane preparing method involves depositing polyether sulfone ultrafiltration membrane with 2-hydroxypropyl trimethyl ammonium chloride cation casting solution, and treating with graphene oxide anion casting solution to obtain multilayered self-assembling composite film. The composite films are laminated with anodic film, dried, immersed in potassium hydroxide, treated with ethanol solution of epoxy chloropropane and subjected for cross linking reaction to obtain the finished product. USE - Method for preparing self-assembled oxidized graphene/quaternized chitosan positively charged composite nanofiltration membrane. ADVANTAGE - The method enables preparing self-assembled oxidized graphene/quaternized chitosan positively charged composite nanofiltration membrane with good hydrophilicity, good separating effect, good stability and high interception rate, in eco-friendly manner. DETAILED DESCRIPTION - A self-assembled oxidized graphene/quaternized chitosan positively charged composite nanofiltration membrane preparing method involves depositing polyether sulfone ultrafiltration membrane as a base film with 4.0-6.0 mg/ml 2-hydroxypropyl trimethyl ammonium chloride cation casting solution for 15-20 minutes, and treating with 0.25-1.5 mg/ml graphene oxide anion casting solution for 15-20 minutes to obtain multilayered self-assembling composite film. The multilayered self-assembling composite films are laminated with a layer of anodic film, dried, immersed in potassium hydroxide, treated with ethanol solution of epoxy chloropropane to adjust pH to 8.5 plus minus 0.5, and subjected for cross linking reaction at 50 degrees C for 21-24 hours to obtain the finished product.