▎ 摘　　要

NOVELTY - Preparation of graphene modified polyamide-polyethersulfone composite microporous nanofiltration membrane involves (s1) performing nitration modification on a polyether sulfone by using a mixed acid of concentrated nitric acid and concentrated sulfuric acid to obtain nitrated polyether sulfone, (s2) adding the obtained aminated polyether sulfone into a tetrahydrofuran solvent, (s3) adding a pore-forming agent lithium chloride and sulfonated polyether sulfone into an N-methyl pyrrolidone solvent, (s4) adding p-phenylenediamine and graphene into a toluene solvent in a mass ratio of 60-150:100, (s5) adding the obtained aminated graphene into an N,N-dimethylacetamide solvent, ultrasonically dispersing, dripping N,N-dimethylacetamide solution of terephthaloyl chloride in an ice-water bath in a nitrogen atmosphere, and (s6) adding 1,4-xylylenediamine into a deionized water solvent, draining, immersing into the oil phase solution for 10-30 seconds, drying, washing and drying. USE - Preparation of graphene modified polyamide-polyethersulfone composite microporous nanofiltration membrane used for separating various organic material and inorganic salts with different valence states. ADVANTAGE - The graphene modified polyamide-polyether sulfone composite microporous nanofiltration membrane has excellent hydrophilicity, anti-pollution performance, and durability. DETAILED DESCRIPTION - Preparation of graphene modified polyamide-polyethersulfone composite microporous nanofiltration membrane involves (s1) performing nitration modification on a polyether sulfone by using a mixed acid of concentrated nitric acid and concentrated sulfuric acid to obtain nitrated polyether sulfone, and further performing amination modification on the nitrated polyether sulfone by using a diluted hydrochloric acid solution of stannous chloride to obtain aminated polyether sulfone, (s2) adding the obtained aminated polyether sulfone into a tetrahydrofuran solvent, ultrasonically dispersing, dripping the tetrahydrofuran solution of 1,3-propanesultone while stirring at 40-60℃, reacting, cooling, performing suction filtration, washing and drying to obtain sulfonated polyether sulfone, (s3) adding a pore-forming agent lithium chloride and sulfonated polyether sulfone into an N-methyl pyrrolidone solvent, ultrasonically dispersing, leaving in vacuum for defoaming, scraping a nascent state membrane on a glass plate, placing in deionized water, performing coagulation bath at 40-60℃ for 2-10 minutes, then placing in deionized water at 50-70℃ for soaking for 6-10 hours to remove the pore-forming agent, washing and drying to obtain a sulfonated polyether sulfone basement membrane, (s4) adding p-phenylenediamine and graphene into a toluene solvent in a mass ratio of 60-150:100, heating to 50-80℃, performing amination modification for 6-12 hours, filtering, and washing with dichloromethane to obtain aminated graphene, (s5) adding the obtained aminated graphene into an N,N-dimethylacetamide solvent, ultrasonically dispersing, dripping N,N-dimethylacetamide solution of terephthaloyl chloride in an ice-water bath in a nitrogen atmosphere, ultrasonically dispersing, reacting, performing reduced pressure suction filtration, washing and drying to obtain functionalized graphene, and (s6) adding 1,4-xylylenediamine into a deionized water solvent, ultrasonically dispersing, adding triethylamine to adjust the pH value of the solution to 8-9, adding sodium dodecyl sulfate as a surfactant to obtain a water phase solution, adding terephthaloyl chloride and functionalized graphene into Isopar G (RTM: isoparaffinic hydrocarbon) solvent, ultrasonically dispersing to obtain an oil phase solution, immersing a sulfonated polyether sulfone base membrane into the water phase solution for 1-5 minutes, draining, immersing into the oil phase solution for 10-30 seconds, drying, washing and drying.