The Preparation Of Temperature-sensitive Coupling Membrane And Its Catalytic Separation Performance

The membrane with the function of catalytic and separation not only separates the specific component from mixed solution,but also has catalytic activity to enhance decontamination efficiency.In addition,noble metal Pd catalyst has good catalytic performance,but its wide application in the catalytic field was limited for its small particle size,high surface energy and easy agglomeration.In this paper,the advantages of physical and chemical stability of PVDF materials and highly efficient catalytic performance of Pd nanoparticles are considered.A new kind of catalytic membrane with Pd nanoparticles distributed on the porous wall was developed by non-solvent induced phase separation,and the temperature response of the membrane was given by two different ways.The intelligent application of PVDF membrane in the field of nitrobenzene compounds'catalysis was realized.1.Preparation of thermo-sensitive composite membrane with PVDF/P(NIPAM-co-AA).A novel thermo-sensitive catalytic membrane was prepared by blending poly(vinylidene fluoride)(PVDF)with P(NIPAM-co-AA)microgels prepared by free radical polymerization.EDX,SEM,AFM confirmed that the microgels existed in the membrane pores and the Pd nanoparticles were distributed on the surface of the microgels.The membrane showed a thermo-sensitive permeability due to swelling and/or shrinkage of the microgels,which changed the permeability of the membrane pore.The thermo-sensitive membrane can effectively catalyze the toxic 2-nitroaniline by penetrative or cyclic cross flow.Under the condition of penetrative degradation,the membrane exhibited a new thermal response catalytic behavior.High conversion rate and high conversion efficiency can be achieved at the same time only by adjusting temperature.2.The preparation of thermo-sensitive semi-IPN/PVDF catalytic coupling membrane.The PVDF powder and PM A A microspheres synthesized by distillation precipitation were mixed and scraped to membranes.After alkali treatment,palladium ion chelation,in situ reduction,palladium metal nanoparticles were attached to the PMAA microspheres to form substrate membrane.Secondly,the PVDF./P(NIPAM-AA)semi-interpenetrating network copolymer(semi-IPN)was uniformly coated on the substrate surface to prepare the coupling membrane.The composition of the coupling membrane was confirmed by EDS and ATR-FTIR spectra.SEM and AFM showed the coating effect on the pore and surface.The semi-IPN coating given the membrane temperature response and selectively separated.The membrane flux can be controlled and the conversion efficiency can be improved by adjusting the temperature.The coupling membrane has good catalytic stability and durability.