▎ 摘　　要

NOVELTY - Composite film comprises 90-99 wt.% polyethersulfone, 0.01-10 wt.% graphene oxide powder, 0.5 wt.% porogen and 30 wt.% dimethyl formamide. USE - Composite film used for absorbing heavy metals pollutants such as lead ions (II), copper (II) ions and organic dyes i.e. methylene blue from industrial wastewater (claimed). ADVANTAGE - The composite film treats industrial wastewater in order to remove heavy metals pollutants in a simple and cost-effective manner. The composite film has high adsorption rate as well as capacity to achieve the purification of industrial wastewater on large scale. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing composite film , which involves: (A) adding graphene oxide powder to dimethyl formamide, where the mixture is subjected to sonication at 200 Watt for 2 hours; (B) cooling the agitated mixture, followed by addition of polyethersulfone; (C) degassing the formed intermediate film, which is scraped from the reaction container and then subjected into water coagulation bath comprising deionized water at 60-70 degrees C to remove the solvent; (D) adding graphene oxide and porogen to the solvent free-intermediate film, and then heating the obtained mixture at 40-60 degrees C under stirring condition for 12-24 hours to obtain casting film; and (E) rinsing the obtained casting film with deionized water, and then drying it to obtain the finished product.