▎ 摘　　要

NOVELTY - The preparation of graphene composite foam involves preparing graphene oxide aqueous solution, and ultrasonically dispersing to form graphene oxide dispersion liquid, adding with dopamine, ultrasonically dispersing, reducing dopamine to graphene oxide layer and performing cross-linking and self-polymerization reaction of dopamine, and reacting at high temperature to obtain reduced graphene oxide-poly dopamine hydrogel, removing the hydrogel from reactor, cooling, cleaning with pure water to remove excess poly dopamine, and immersing hydrogel into chitosan acetic acid solution. USE - Preparation method of graphene composite foam for separating oil and water. ADVANTAGE - The method enables preparation of graphene composite foam with excellent superhydrophobic characteristics, flexibility, high selective separation efficiency, prolonged circulating service life, non-toxicity, and antibacterial effect, by simple and environmentally-friendly process. DETAILED DESCRIPTION - The preparation method of graphene composite foam involves (1) preparing 1-5 mg/ml graphene oxide aqueous solution, and ultrasonically dispersing to form graphene oxide dispersion liquid, (2) adding dopamine to the graphene oxide dispersion liquid while adjusting the pH value of the mixed solution to 7-9, ultrasonically dispersing for 5-10 minutes, reducing dopamine to graphene oxide layer and performing cross-linking and self-polymerization reaction of dopamine, placing in a reactor, and reacting at 120-180 degrees C high temperature for 12-15 hours to obtain reduced graphene oxide-poly dopamine hydrogel, where the mass ratio of graphene oxide and dopamine is 0.5-2, (3) removing the hydrogel from the reactor, cooling to room temperature, completely cleaning with pure water to remove excess poly dopamine, immersing the hydrogel into 8-12 mg/ml chitosan acetic acid solution, and reacting for 6-12 hours, (4) removing the hydrogel from the chitosan acetic acid solution, completely cleaning with pure water for removing unreacted chitosan, freeze-drying at -40 to -55 degrees C, and vacuum drying at 8-15 Pa for 15-18 hours to obtain chitosan/graphene composite foam of three-dimensional porous structure, and (5) performing liquid phase fluorination treatment of the chitosan/graphene composite foam, where the fluoride is 1H,1H,2H,2H-perfluorodecanethiol, placing into a hot blast oven, and drying at 50-60 degrees C for 12-16 hours.