Preparation And Properties Of Organic-Inorganic Composite Ultrafiltration Membrane Based On Poly(arylene Ether Ketone)with Carboxyl Groups

Water is the source of life,and the recycling and reuse of water resources is crucial to the development of ecology and human survival.As the economy of society progresses and the quality of human life improves,domestic wastewater is also increasing,and how to carry out wastewater treatment to achieve a better life is a matter of concern.The wide application of membrane separation technology has been recognized by the public.Meanwhile,ultrafiltration membrane（UF）,as an important branch of separation membrane technology,has great potential development prospects for application in various aspects of life.However,the ultrafiltration membranes are costly and have the disadvantages of lower permeability,less selectivity and weaker resistance to contamination,all of which are closely related to the structural properties of the membranes themselves.In this paper,we prepared a series of ultrafiltration membranes with poly（arylene ether ketone）polymers as membrane substrate and a composite material synthesized from graphene oxide（GO）and metal organic framework（Ui O-66-NH₂）as the filler to achieve high permeability and high retention rate,as well as strong anti-pollution ultrafiltration membrane.In recent years,metal-organic frameworks（MOFs）have attracted attention due to their open crystal structure,which makes them highly flexible in terms of modifying physical and chemical properties.The modified MOFs have a large specific surface area and large porosity.In the first work of this paper,Ui O-66-NH₂ one of the MOFs,was selected as a filler,which has a large thermal stability and a hydrophilic group amino group,and its properties are beneficial to improve the permeate flux and antifouling ability of ultrafiltration membranes.The results showed that with the addition of the filler Ui O-66-NH₂,the hydrophilicity of the membrane decreased from 72.4°to 55.6°,and the permeate throughput of the composite ultrafiltration membrane increased significantly from 294.53 L/（m²h）of the initial membrane to 555.5 L/（m²h）,and the retention for the contaminant model BSA could reach 97.8%,with the maximum recovery being 77.4%.PAEK-COOH@Ui O-66-NH₂ composite ultrafiltration membranes improve permeability and selectivity,but the resistance to contamination needs to be improved.Based on the first work,we synthesized the sandwich structure Ui O-66-NH₂@GO,and prepared the cast film solution by co-blending method,and the ultrafiltration membrane by NIPS method,the presence of carboxyl-containing poly（arylene ether ketone）carboxyl group can interact with the amino group in the filler to form hydrogen bonding interaction,while the intermolecular group interaction forms amide bond,which makes the addition of the filler improve the compatibility with the carboxyl-containing The addition of filler improves the compatibility with the poly（arylene ether ketone）substrate material containing carboxyl groups and further improves the stability of the ultrafiltration membrane.For a series of additions with different contents of Ui O-66-NH₂@GO,the membrane permeability and selective antifouling properties were substantially improved.The flux was as high as 591.25 L/（m²h）when the loading was 0.06 wt.%.Following the increase of filler,the mechanical properties of the membranes increased from 2095.12 KPa to 3469.57 KPa,which was 1.66 times higher,while the flux recovery rate increased to81.67%,and the overall performance of the composite ultrafiltration membranes was improved.