Pdms/pan Hollow Fiber Composite Membrane For Methanol-water Separation

As one of novel membrane separation process, membrane contactor has many advantages such as lower investment, less energy consumption, easy operation and pollution-free. Due to its specific characteristic, membrane contactor has become a promising technique with outstanding technical advantages and potential application prospects.PDMS composite membranes were prepared with crosslinked DMS using polyacrylonitrile (PAN) as substrate. The effects of the concentration of DMS, crosslinker, catalyst and dipping time on membrane gas permeability were also investigated. The optimum prescription and operation conditions for active layer of composite membrane preparing were determined.The structure of PAN hollow fiber substrate membrane and composite membranes made were analyzed by Fourier Transform Infrared Spectroscopy (FT-IR) and SEM. The hydrophobicity of membranes was characterized by water contact angle. Resulted indicated that crosslink reaction of DMS occurred in the process. The active layer of PDMS was dense and uniform. The internal structure of composite membranes was affected by concentration of cross linker and catalyst.The hollow fiber PAN and PAN-PDMS composite membrane contactor were then used to separate methanol-water mixture for comparison. Results showed that membrane material affected the performance of membrane contactor in distillation. The PAN-PDMS composite membrane contactor occupied higher separation efficiency than that of PAN in both distillate concentration and height of mass transfer unit (HTU).