Preparation And Properties Of Novel MOFs/Poly(Arylene Ether Sulfone) Reactive Hybrid Ultrafiltration Membranes

With the development of society,the water consumption of domestic and industry is increasing.So it is extremely urgent to solve the problem of water shortage.Due to the unique advantages of ultrafiltration separation technology,it is widely used in water treatment.However,the problem of membrane fouling limits the application of ultrafiltration separation technology.In this paper,a series of high-performance,self-cleaning and anti-pollution reactive hybrid ultrafiltration membranes with solar light response capability were prepared by molecular design.The structure and morphology of materials were characterized by X-ray diffraction（XRD）,fourier transform infrared spectroscopy（FT-IR）and scanning electron microscopy（SEM）.The optical properties of photocatalytic materials were analyzed by UV-visible diffuse reflectance spectroscopy（UV-vis/DRS）.The contact angle（CA）was used to analyze the hydrophilic properties of the ultrafiltration membrane.The effects of MOFs on the performance of ultrafiltration membranes were investigated by using azo dye as the target pollutant.The research includes the following points:（1）A series of sheet-shaped photocatalytic materials named NH₂-MIL-125 and Ag@NH₂-MIL-125（Ag content was 1%,3%and 5%）were prepared by hydrothermal synthesis and photodeposition,respectively.The UV-vis/DRS result shows that the spectral absorption range of the catalyst was broadened by the introduction of Ag.The degradation performance of the photocatalytics was evaluated by the degradation efficiency of Congo red under simulated sunlight for 90 min.The result shows that the introduction of Ag can improve the degradation ability of the photocatalyst.When the Ag doping amount is 3%,the removal of Congo red is the highest,reaching 99.7%.（2）The NH₂-MIL-125 photocatalytic material mentioned above was grafted to the synthesized fluorine-containing carboxyl group-containing polyaryl ether sulfone PAES-CF₃-COOH matrix side chain by chemical bonding.A series of NH₂-MIL-125/PAES-CF₃-COOH reactive hybrid ultrafiltration membranes were prepared containing 1%,3%,and 5%NH₂-MIL-125,respectively.The results of ultrafiltration separation experiments show that the flux,anti-pollution ability and self-cleaning ability of solar light response of ultrafiltration membranes increase with the increase of NH₂-MIL-125 content in hybrid ultrafiltration membranes.When the NH₂-MIL-125content is 5%,the hybrid ultrafiltration membrane exhibits optimal water flux and pollution resistance.In addition,after 10 minutes of simulated sunlight,the water flux recovery rate can reach 93.7%,showing excellent self-cleaning performance,and the retention rate of pollutants after self-cleaning can still be maintained above 95.0%.（3）In order to further improve the solar response self-cleaning ability of the ultrafiltration membrane,after preferred the mass fraction of the photocatalyst in the hybrid material is 5%and bonded the better photocatalytic activity of Ag@NH₂-MIL-125 to polymer matrix material by chemical to prepare a series of Ag@NH₂-MIL-125/PAES-CF₃-COOH reactive hybrid ultrafiltration membranes.And investigated the performance of ultrafiltration membranes by changing the content of Ag in Ag@NH₂-MIL-125（mass fraction 1%,3%,5%）.It is found that the change of Ag content in the catalyst has little effect on the separation performance and anti-pollution performance of the ultrafiltration membranes,but can significantly improve the self-cleaning ability of the ultrafiltration membranes.When the content of Ag in the catalyst is 3%,the water flux recovery rate of the hybrid ultrafiltration membrane reaches 99.0%after 10 min under simulated sunlight,showing the best self-cleaning ability and the retention rate of pollutants still remained above 94.6%.