Using a liquid-solid phase inversion method, a hybrid matrix poly(vinylidene fluoride)(PVDF) membrane was prepared with alumina(Al2O3) nanoparticle addition. Pd/Fe nanoparticles(NPs) were successfully immobili...Using a liquid-solid phase inversion method, a hybrid matrix poly(vinylidene fluoride)(PVDF) membrane was prepared with alumina(Al2O3) nanoparticle addition. Pd/Fe nanoparticles(NPs) were successfully immobilized on the Al2O3/PVDF membrane, which was characterized by Scanning Electron Microscopy(SEM) and Transmission Electron Microscopy(TEM). The micrographs showed that the Pd/Fe NPs were dispersed homogeneously. Several important experimental parameters were optimized, including the mechanical properties, contact angle and surface area of Al2O3/PVDF composite membranes with different Al2O3 contents. At the same time, the ferrous ion concentration and the effect of hydrophilization were studied. The results showed that the modified Al2O3/PVDF membrane functioned well as a support. The Al2O3/PVDF membrane with immobilized Pd/Fe NPs exhibited high efficiency in terms of dichloroacetic acid(DCAA) dechlorination. Additionally, a reaction pathway for DCAA dechlorination by Pd/Fe NPs immobilized on the Al2O3/PVDF membrane system was proposed.展开更多
In the present study,nano-sized TiO2 /Al2O3 modified PVDF membranes (MM) were fabricated and utilized for anionic polyacrylamide ( APAM) separation. The results showed that,compared with PVDF membrane (OM) ,the contac...In the present study,nano-sized TiO2 /Al2O3 modified PVDF membranes (MM) were fabricated and utilized for anionic polyacrylamide ( APAM) separation. The results showed that,compared with PVDF membrane (OM) ,the contact angle of MM decreases from 83. 64° to 67. 42°,which indicates the increase of the hydrophilicity of MM. The relative flux (RF) decline curve of this ultrafiltration of APAM in water with time shows an obvious two stage properties. The cake filtration models were used to predict the performance of different time over the complete range of filtration times. All the four cake models could simulate this UF process to a certain extent,and the suitability of the two kinds of membranes was: cake filtration > intermediate pore blocking > standard pore blocking > complete pore blocking models. However,they became more and more unsuited to this process with time extending. Surface and cross-sectional morphology of membrane was investigated by SEM to make an advanced certificate of this UF mechanism.展开更多
基金supported by the Nature Science Foundation of Heilongjiang Province (No. B201410)the Postdoctoral Foundation Project of Heilongjiang Province (No. LBH-Z13128)+3 种基金the Science and Technology Research Program of Education Bureau of Heilongjiang Province (No. 12531206)the Special Scientific Research Projects of Harbin Normal University (12XQXG02)the National Nature Science Foundation of China (No. 41030743)the National Nature Science Foundation of China (No. 42171217)
文摘Using a liquid-solid phase inversion method, a hybrid matrix poly(vinylidene fluoride)(PVDF) membrane was prepared with alumina(Al2O3) nanoparticle addition. Pd/Fe nanoparticles(NPs) were successfully immobilized on the Al2O3/PVDF membrane, which was characterized by Scanning Electron Microscopy(SEM) and Transmission Electron Microscopy(TEM). The micrographs showed that the Pd/Fe NPs were dispersed homogeneously. Several important experimental parameters were optimized, including the mechanical properties, contact angle and surface area of Al2O3/PVDF composite membranes with different Al2O3 contents. At the same time, the ferrous ion concentration and the effect of hydrophilization were studied. The results showed that the modified Al2O3/PVDF membrane functioned well as a support. The Al2O3/PVDF membrane with immobilized Pd/Fe NPs exhibited high efficiency in terms of dichloroacetic acid(DCAA) dechlorination. Additionally, a reaction pathway for DCAA dechlorination by Pd/Fe NPs immobilized on the Al2O3/PVDF membrane system was proposed.
基金Sponsored by the National Natural Science Foundation of China (Grant No.50978068)International Cooperation Program (Grant No.2010DFA92460)+1 种基金National High Technology Research and Development Program of China (863 Program,Grant No.2008AA06Z304)Tianjin Key Laboratory of Aquatic Science and Technology
文摘In the present study,nano-sized TiO2 /Al2O3 modified PVDF membranes (MM) were fabricated and utilized for anionic polyacrylamide ( APAM) separation. The results showed that,compared with PVDF membrane (OM) ,the contact angle of MM decreases from 83. 64° to 67. 42°,which indicates the increase of the hydrophilicity of MM. The relative flux (RF) decline curve of this ultrafiltration of APAM in water with time shows an obvious two stage properties. The cake filtration models were used to predict the performance of different time over the complete range of filtration times. All the four cake models could simulate this UF process to a certain extent,and the suitability of the two kinds of membranes was: cake filtration > intermediate pore blocking > standard pore blocking > complete pore blocking models. However,they became more and more unsuited to this process with time extending. Surface and cross-sectional morphology of membrane was investigated by SEM to make an advanced certificate of this UF mechanism.