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In the propylene polymerization process in order to prevent catalyst poisoning, the water content in the raw material gas should be strictly controlled. To meet the industrial demand, the propylene / water vapor gas mixture as a model system, two high dehumidifying performance composite film prepared by hybrid modified. Using scanning electron microscopy (SEM), differential scanning calorimetry thermal (DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) analysis were used to characterize the physical and chemical structure of the film and the morphology using positron annihilation lifetime spectroscopy (PALS) free volume properties of the film. The use of hyaluronic acid (HA) of adhesion, the introduction of HA buffer layer at the interface between the polyvinyl alcohol (PVA) polymer and an inorganic oxide of silicon (silica), and enhance the adhesive action of PVA and silica interface, eliminating the interfacial defects. HA has a strongly hydrophilic, and can increase the adsorption selectivity of the film on the water molecules to promote the transfer of water molecules in the film. First, the system through the the HA modified silicon oxide particles blended with PVA PVA--(HA-silica) membrane casting solution, and then using a dip coating method, and polysulfone (PS) made of a porous film of PVA-(HA-silica) / PS composite membrane. Compared to PVA / PS membrane (permeability coefficient 215 GPU, the separation factor of 4720), the PVA-(HA-silica) / PS films significant improve propylene disabsorbing performance, when the HA concentration of 0.2 wt.%, HA-silica filling the amount of 4%, the permeability coefficient of the composite film 912 GPU, the separation factor of 9650. Biomineralization process inspired blend of polymer solutions in polyvinyl alcohol - gelatin (PVA-gelatin), sodium silicate as a silicon precursor, by the gelatin induction mineralization in situ synthesis (PVA-gelatin) -silica hybrid membranes. Gelatin to play its role of catalyst and template, induced oxidation of silicon nucleation and growth; PVA polymer chain growth of silicon oxide provides a confined space, inhibiting the reunion of the silicon oxide particles evenly dispersed in the polymer body. In this hybrid membrane separation layer, a polysulfone porous membrane as a support layer prepared (PVA-Gelatin) -silica/PS composite membranes demonstrated a good de-wet performance. When the solution pH = 5.0, and the sodium silicate concentration of 30 mM, the permeability coefficient of the composite membrane was 1500 GPU, separation factor reaches 67511. Adsorption experiments showed that the water molecules in the PVA-(HA-silica) and (PVA-gelatin)-silica film in the transfer process is mainly controlled by the diffusion step. Systematically investigated the influence of the conditions and the process parameters such as temperature, pressure, flow rate of the silicon oxide filling amount, pH value, the concentration of the precursor film of the composite membrane disabsorbing performance. The dehumidifying process for propylene depth, hollow fiber composite membrane for membrane materials, application of the membrane process of dehumidification technology coupled with traditional gas outlook.
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