| Hollow fiber membrane extraction process is combined with liquid-liquid extraction of new separation technologies, especially for metal ions, heat-sensitive material and difficult to separate physical separation and extraction. With the traditional liquid-liquid extraction process, compared with membrane extraction mass transfer area, extraction efficiency, low consumption, little environmental pollution and flooding and no back mixing, extraction and less loss of advantage. Currently, the technology applied in the initial stage of industrialization, is one of the hot research field of environmental protection. So many problems are worth studying.In this thesis, the hydrophobic PVDF hollow fiber membrane for the mass transfer interface, with efficient extractant Cyanex 923-kerosene-NaOH aqueous solution was simulated Phenol extraction- stripping experiments to study the mass transfer of two ways, water phase and organic phase flow rate, initial concentration of water, membrane loading factor, ionic strength, membrane modules in series and anti-phase extraction and concentration of operating conditions on the extraction rate and mass transfer properties. And on this basis, the actual extraction of coal gasification wastewater was experimental.The results of the extraction equilibrium curve fitting and calculating the distribution coefficient and the concentration of phenol in the aqueous phase relationship: logD=1.62-0.077caq. pH values have a major impact on the distribution coefficient, when the pH>8, the distribution coefficient decreased rapidly. Increase the water phase flow rate can significantly speed up the extraction process and increase the mass transfer coefficient, the organic phase flow rate change is not effected by the mass transfer coefficient. It shows that the water phase boundary layer mass transfer resistance is the resistance of the controlling factors, the results also show that the organic layer resistance and membrane phase resistance account for less than 20%. In the water phase flow rate of 0.002m/s~0.016m/s within the modules and mass transfer unit height of 0.17m~0.75m, significantly less than traditional extraction equipment. Increasing initial concentration of water, However, reduce the overall mass transfer coefficient. On the one hand, distribution coefficients with the initial concentration decreases, on the other hand, increasing the concentration and mass concentration polarization on both sides of the interface phenomenon. Membrane packing factor and uniform distribution of film and the density levels have a significant impact on mass transfer. Increase the filling factor can increase the mass transfer area, but the membrane smaller wire spacing, prone to compression phenomena, mass transfer coefficient decreased. Series of low packing factor of the membrane can reduce the extraction time, save the investment. Salt effect can promote the mass transfer process. Therefore, by increasing the ionic strength to reinforce the water phase mass transfer.When the NaOH concentration from 0.1mol/L increased to 0.5mol/L, the anti-extraction coefficient was 4.83×10-7m/s increased to 5.93×10-7m/s. Phenol recovery of more than 93%. Mass transfer coefficient against mass transfer coefficient than an order of magnitude, which is due to stripping of solute mass transfer interface, there is no pre-adsorption edge.SS content in the actual waste water on the extraction rate significantly affected by coagulation pretreatment, mass transfer speed. In the continuous countercurrent extraction experiments, the water phase flow rate increases within a certain range can increase the extraction rate, but the extraction rate over the range began to decrease. Membrane modules in series to extend the contact time between the two phases, extraction rates increased. On the membrane long used SEM tests found no membrane fouling, indicating a strong antifouling membrane extraction.
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