Ultrafiltration membrane fabrication materials

Performance improvement of polysulfone ultrafiltration membrane has been achieved by blending with PANI-NFs [457]. Conducting blends of nanostruetured PANI and PANI-clay nanocomposites with ethylene vinyl acetate as host matrix have been prepared [458]. A new conducting hybrid biocompatible composite material of PANI-NFs well dispersed in a collagen matrix was fabricated with various PANI-NFs/eoUagen ratios [459]. PANI-NFs doped by protonic acids can be efficiently dispersed in vinylidene fluoride-trifluoroethylene copolymers [460]. Fabrication of MWCNTs/PANI-NF nanocomposites via electrostatic adsorption in aqueous colloids has been reported [143]. A PANI-NFs/ carbon paste electrode was prepared via dopping PANI-NFs into the carbon paste [461]. 

Furthermore, the FT-IR analytical technique was ap>plied in analysis of surface of membranes interacted with other materials. For instance, Luo et. al., fabricated the SPES/Nano-Ti02 composite ultrafiltration membrane. In their studies, the Ti02 nanoparticle self-assembly on the SPES membrane surface was confirmed by X-ray photoelectron spectroscopy (XPS) and FT-IR spectrometer. When the nano-TiCb was self-assembled on the SPES membrane the absorption peak at 1243 cm-i attributes to the stretching vibration of the ether C-O-C bond in the SPES polymer shifted to 1239 cmri. The result of FT-IR spiectrometer effectively verified the self-assembly process of nano-Ti02 on the SPES membrane.P ... 

Microfiltration and ultrafiltration membranes can be made from organic polymers or inorganic materials such as ceramic, glass, or metal or organic polymers. Materials used in MF and UF membrane fabrication are shown in Table 6.1. A number of different techniques are employed to prepare synthetic MF/UF membranes the most important are phase inversion, coating, sintering, and track etching. 

These copolymers can be sulfonated and fabricated into ultrafiltration and nanofiltration asymmetric membranes. Such a membrane formulation exhibited a 98% rejection rate for poly(ethylene glycol) 12000 and a high pure water flux of 867 kgm h The proton conductivities of the sulfonated materials reach higher than 10 Scm at a degree of sulf-onation of 1.0. Therefore, the use of the materials in fuel cells has been suggested. ... 

Aromatic tri-functional acid and amine monomers are used to obtain reticulated polyamides, which have better mechanical and chemical stability and, for that reason, they are preferred for nanofiltration and reverse osmosis membrane materials. In these membranes, a thin polyamide layer (less than l jm thickness) is fabricated by interfacial polymerization on the top of a porous support (normally an ultrafiltration polysulfone membrane), which usually presents a non-woven reinforcement for mechanical stability as can be seen in Figure 8. Despite its small thickness, the polyamide dense layer is the main regulator of the rejection/transport of water and ions across the membrane. 

The separator is an important component in a MFC, which physically separates the anode and cathode. A variety of separators have been explored for MFCs, including a salt bridge, cation exchange membrane (CEM), anion exchange membrane (AEM), bipolar membrane (BPM), microfiltration (MF) membrane, ultrafiltration (UF) membrane, and porous fabrics and porous materials. 

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