Surface modification by physical adsorption of Tween 20 was accomplished on polypropylene microporous membranes (PPMMs). Attenuated total reflection-Fourier transform infrared spectroscopy (ATR/FT-IR) and field em...Surface modification by physical adsorption of Tween 20 was accomplished on polypropylene microporous membranes (PPMMs). Attenuated total reflection-Fourier transform infrared spectroscopy (ATR/FT-IR) and field emission scanning electron microscope (FE- SEM) were used to characterize the chemical and morphological changes on the membrane surfaces. Water contact angles and relative pure water fluxes were measured. The data showed that the hydrophilic performance for the modified membranes increased with the increase in the adsorption amount of Tween 20 onto the surface or into the pores of polypropylene microporous membranes. To test the antifouling property of the membranes by the adsorption of Tween 20 in a membrane bioreactor (MBR), filtration for active sludge was performed using synthetic wastewater. With the help of the data of water fluxes and the FE-SEM photos of the modified PPMMs before or after operating in a MBR for about 12 d, the PPMMs with monolayer adsorption of Tween 20 showed higher remained flux and stronger antifouling ability than unmodified membrane and other modification membranes studied.展开更多
To improve its limiting flux and antifouling characteristics in a submerged membrane-bioreactor (SMBR) for wastewater treatment, polypropylene hollow fiber microporous membrane (PPHFMM) was surface-modified by the...To improve its limiting flux and antifouling characteristics in a submerged membrane-bioreactor (SMBR) for wastewater treatment, polypropylene hollow fiber microporous membrane (PPHFMM) was surface-modified by the plasma-induced immobilization of poly (N-vinyl-2-pyrrolidone) (PVP) and the plasma treatment with different gases respectively. Attenuated total reflection-Fourier transform infrared spectroscopy (FT-IR/ATR), X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscope (FE-SEM) were used to characterize the structural and morphological changes on the membrane surface. Water contact angle was measured by the sessile drop method. It was found that the water contact angle was 128.8, 72.3, 62.7, 74.4, 79.1, 86.3, and 71.3° for the nascent, PVP-immobilized, air, 02, Ar, CO2 and H2O plasma treated PPHFMM, respectively. The SMBR was operated at fixed transmembrane pressure to determine the limiting flux for the PPHFMM before and after surface modification. Results showed that the limiting flux appeared to be 103, 159, 117, 133, 136, 121 and 152 L/(m^2· h) for the nascent, PVP-immobilized, air, O2, At, CO2 and H2O plasma treated PPHFMM, respectively. After continuous operation for about 50 h in the SMBR, the antifouling characteristics were improved to some extent.展开更多
基金Project supported by the High-Tech Research and Development Program (863)of China(No.2002AA601230)the Science-Research Program of Jiaxing City,China(No.2005AY3013).
文摘Surface modification by physical adsorption of Tween 20 was accomplished on polypropylene microporous membranes (PPMMs). Attenuated total reflection-Fourier transform infrared spectroscopy (ATR/FT-IR) and field emission scanning electron microscope (FE- SEM) were used to characterize the chemical and morphological changes on the membrane surfaces. Water contact angles and relative pure water fluxes were measured. The data showed that the hydrophilic performance for the modified membranes increased with the increase in the adsorption amount of Tween 20 onto the surface or into the pores of polypropylene microporous membranes. To test the antifouling property of the membranes by the adsorption of Tween 20 in a membrane bioreactor (MBR), filtration for active sludge was performed using synthetic wastewater. With the help of the data of water fluxes and the FE-SEM photos of the modified PPMMs before or after operating in a MBR for about 12 d, the PPMMs with monolayer adsorption of Tween 20 showed higher remained flux and stronger antifouling ability than unmodified membrane and other modification membranes studied.
基金The Hi-Tech Research and Development Program (863) of China (No. 2002AA601230)
文摘To improve its limiting flux and antifouling characteristics in a submerged membrane-bioreactor (SMBR) for wastewater treatment, polypropylene hollow fiber microporous membrane (PPHFMM) was surface-modified by the plasma-induced immobilization of poly (N-vinyl-2-pyrrolidone) (PVP) and the plasma treatment with different gases respectively. Attenuated total reflection-Fourier transform infrared spectroscopy (FT-IR/ATR), X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscope (FE-SEM) were used to characterize the structural and morphological changes on the membrane surface. Water contact angle was measured by the sessile drop method. It was found that the water contact angle was 128.8, 72.3, 62.7, 74.4, 79.1, 86.3, and 71.3° for the nascent, PVP-immobilized, air, 02, Ar, CO2 and H2O plasma treated PPHFMM, respectively. The SMBR was operated at fixed transmembrane pressure to determine the limiting flux for the PPHFMM before and after surface modification. Results showed that the limiting flux appeared to be 103, 159, 117, 133, 136, 121 and 152 L/(m^2· h) for the nascent, PVP-immobilized, air, O2, At, CO2 and H2O plasma treated PPHFMM, respectively. After continuous operation for about 50 h in the SMBR, the antifouling characteristics were improved to some extent.