Preparation Of Superhydrophilic Membrane And Its Application In Emulsion Separation

With the progress of society and the rapid development of industry,environmental problems have become increasingly serious.Among the many types of pollution,water pollution is a problem that deserves special attention.In the process of people’s production and life,a large amount of waste is discharged into the water.As a result,people have studied many oil-water separation membranes prepared using a special wetting principle,which has more obvious advantages than traditional industrial treatment methods,can quickly and efficiently separate oily wastewater.Moreover,it can obtain more additional functions after modification.Therefore,this kind of material has been deeply studied by many researchers.In this paper,a series of oil-water separation membranes based on inorganic compounds and polymers are designed and prepared for the efficient separation of emulsions,and other pollutants in the emulsion are targeted for research,which can achieve the dual effects of separation and treatment.(1)One-step hydrothermal method was used to prepare iodine-doped bismuth subcarbonate nanosheets coated carbon cloth.Bismuth subcarbonate nanosheets are evenly distributed on the surface of the carbon cloth fibers,forming a cumulative layered microstructure,which gives the material special super-wetting properties.This material can efficiently separate oil-in-water emulsions.Through separation experiments of toluene-in-water emulsions,it can be confirmed that the maximum separation efficiency of the material can reach 99.9%,and the separation efficiency can still reach a high level after multiple cycles.(2)Based on copper mesh,a manganese molybdate-coated copper mesh was prepared by simple hydrothermal methods.The material has both emulsion separation and photocatalytic degradation of organic dyes.The wettability characterization,emulsion separation experiments and dye photocatalytic degradation experiments were performed on the materials to study their practical application capabilities.The prepared material is superamphiphilic in air and superoleophobic under water,and has a separation efficiency of more than 99.5%for a variety of oil-in-water emulsions.In addition,the material also has good recycling ability and can be reused after recycling and cleaning.(3)An EDTA-modified MOF-808 polyacrylonitrile membrane was prepared by solvothermal method and electrospinning method,which could simultaneously separate oil-in-water emulsion and adsorb heavy metal ions.After modified by EDTA,MOF-808 has improved the adsorption capacity and broadened the types of ions.Corresponding tests show that the membrane has high separation and adsorption efficiency,good recycling and corrosion resistance,and can be regenerated by treatment after use.In summary,a series of synthesized inorganic and polymer membranes have high emulsion separation efficiency,and have the effects of catalysis,adsorption,etc.,and have a relatively good application prospect in the field of emulsion separation.