Structures and Separation Properties of PAN−Fe₃O₄ Ultrafiltration Membranes Prepared under an Orthogonal Magnetic Field

Abstract

Novel organo-mineral membranes were prepared under an external orthogonal magnetic field from suspensions by the phase inversion process. The suspensions consist of polyacrylonitrile, dimethyl sulfoxide, poly-(vinylpyrrolidone), and ferrosoferric oxide.The cross-section structures observed by SEM show that the magnetic field can control the alignment orientation of magnetic Fe 3 O 4 aggregates in the membrane. Moreover, the addition of Fe 3 O 4 can lead to the change of macrovoids in the sublayer from being tidy and perpendicular to the membrane plane to being irregular and oblique to the membrane plane. The retention rate of PAN-Fe 3 O 4 membranes to BSA decreases with the increase of Fe 3 O 4 amount and the changes in the retention rate are within a range of 2%. Furthermore, 1 wt % Fe 3 O 4 added in PAN membranes may result in a decline of the membrane permeability or the antifouling performance. But the membrane permeability and the antifouling performance then increase with the increase of Fe 3 O 4 amount from 1 to 4 wt %. Contrary to common results, the membrane permeability and the antifouling performance appear to have no direct correlation to the roughness of membrane surface obtained by AFM.

Multi-walled carbon nanotubes (MWCNTs) mixed polyacrylonitrile (PAN) ultrafiltration membranes

“…observed an improvement of PAN membrane properties using Fe 3 O 4 fillers. 23 In the present study, hydroxyl functionalized MWCNTs were used as fillers in PAN ultrafiltration membranes to improve the membrane transport properties and their mechanical stability. The membrane morphology was studied by SEM analysis while the dispersion of MWCNTs was investigated by TEM.…”

Fabrication of polyethersulfone-mesoporous silica nanocomposite ultrafiltration membranes with antifouling properties

“…Among these methods, blending with inorganic particles has attracted a great deal of interest due to availability of different types of functional inorganic particles. A variety of inorganic fillers such as titanium dioxide (TiO 2 ), alumina (Al 2 O 3 ), zirconium (ZrO 2 ), silica (SiO 2 ) and Fe 3 O 4 have been used to fabricate inorganic-polymer composite membranes [11][12][13][14][15][16]. Many of these studies indicate that membrane modification enhanced performance, by improving water permeability, mechanical strength, and fouling resistance.…”

Facile Microwave-Assisted Synthesis and Magnetic and Gas Sensing Properties of Fe3O4 Nanoroses

“…Fe 3 O 4 is a common ferrite having a cubic inverse spinel structure. As one of the most important and basic magnetic materials, Fe 3 O 4 has great potential for applications such as multi-terabit magnetic storage devices, ferrofluids, sensors, spintronics, separation processes, and especially biomedical fields. ,,,− During the past decade, nanostructured Fe 3 O 4 have already been prepared with a variety of methods including direct coprecipitation, EDTA-assisted route, interfacial reaction route, FeCO 3 precursor based route, magnetic field induced self-assembly method, ,− vapor−solid process, sonochemical approach, hydrothermal methods, biopolymer-assisted synthesis method, etc. However, the self-assembly of Fe 3 O 4 nanoparticles into various architectures and their morphology-dependent properties were so far less reported. , …”