Fouling-resistant ceramic-supported polymer composite membranes were developed for removal of oil-in-water (O/W) mieroemulsions. The composite membranes were featured with an asymmetric three-layer structure, i.e., ...Fouling-resistant ceramic-supported polymer composite membranes were developed for removal of oil-in-water (O/W) mieroemulsions. The composite membranes were featured with an asymmetric three-layer structure, i.e., a porous ceramic membrane substrate, a polyvinylidene fluoride (PVDF) ultrafiltration sub-layer, and a polyamide/polyvinyl alcohol (PVA) composite thin top-layer. The PVDF polymer was east onto the tubular porous ceramic membranes with an immersion precipitation method, and the polyamide/PVA composite thin top-layer was fabricated with an inteffaeial polymerization method. The effects of the sub-layer composition and the recipe in the inteffaeial polymerization for fabricating the top-layer on the structure and performance of composite membranes were systematically investigated. The prepared composite membranes showed a good performance for treating the O/W microemulsions with a mean diameter of about 2.41μm. At the operating pressure of 0.4MPa, the hydraulic permeability remained steadily about 190L·m^-2·h^-1, the oil concentration in the permeate was less than 1.6mg·L^-1, and the oil rejection coefficient was always higher than 98.5% throughout the operation from the beginning.展开更多
Fixed carrier membrane exhibits attractive CO2 permeance and selectivity due to its transport mechanism of reaction selectivity (facilitated transport). However, its performance needs improvement to meet cost target...Fixed carrier membrane exhibits attractive CO2 permeance and selectivity due to its transport mechanism of reaction selectivity (facilitated transport). However, its performance needs improvement to meet cost targets for CO2 capture. This study attempts to develop membranes with multiple permselective mechanisms in order to enhance CO2 separation performance of fixed carder membrane. In this study, a novel membrane with multiplepermselective mechanisms of solubility selectivity and reaction selectivity was developed by incorporating CO2-selective adsorptive silica nanoparticles in situ into the tertiary amine containing polyamide membrane formed by interfacial polymerization (IP). Various techniques were employed to characterize the polyamide and polyam-ide-silica composite membranes. The TGA result shows that nanocomposite membranes exhlbit superior-thermal stability than pure polyamide membranes. In addition, gas permeation experiments show that both nanocomposite membranes have larger CO2 permeance than pure polyamide membranes. The enhanced CO2/N2 separation performance for nanocomposite membranes is mainly due to the thin film thickness, and multiple permselective mechanisms of solubility selectivity and reaction selectivity.展开更多
A low operating pressure nanofiltration membrane is prepared by interfacial polymerization between m-phenylenediamine (MPDA) and trimesoyl chloride (TMC) using PVC hollow fiber membrane as supporting. A series of ...A low operating pressure nanofiltration membrane is prepared by interfacial polymerization between m-phenylenediamine (MPDA) and trimesoyl chloride (TMC) using PVC hollow fiber membrane as supporting. A series of PVC nanofiltration membranes with different molecular weight cutoff (MWCO) can be obtained by controlling preparation conditions. Chemical and morphological characterization of the membrane surface was carried out by FTIR-ATR and SEM. MWCO was characterized by filtration experiments. The preparation conditions were investigated in detail. At the optimized conditions (40 min air-dried time, aqueous phase containing 0.5% MPDA, 0.05% SDS and 0.6% acid absorbent, oil phase containing 0.3% TMC, and 1 min reaction time), under 0.3 MPa, water flux of the gained nanofiltration membrane reaches 17.8 L/m2-h, and the rejection rates of methyl orange and MgSO4 are more than 90% and 60%, respectively.展开更多
基金Supported by the Trans-century Training Programme Foundation for the Talents by the Ministry of Education of China (No.2002-48).
文摘Fouling-resistant ceramic-supported polymer composite membranes were developed for removal of oil-in-water (O/W) mieroemulsions. The composite membranes were featured with an asymmetric three-layer structure, i.e., a porous ceramic membrane substrate, a polyvinylidene fluoride (PVDF) ultrafiltration sub-layer, and a polyamide/polyvinyl alcohol (PVA) composite thin top-layer. The PVDF polymer was east onto the tubular porous ceramic membranes with an immersion precipitation method, and the polyamide/PVA composite thin top-layer was fabricated with an inteffaeial polymerization method. The effects of the sub-layer composition and the recipe in the inteffaeial polymerization for fabricating the top-layer on the structure and performance of composite membranes were systematically investigated. The prepared composite membranes showed a good performance for treating the O/W microemulsions with a mean diameter of about 2.41μm. At the operating pressure of 0.4MPa, the hydraulic permeability remained steadily about 190L·m^-2·h^-1, the oil concentration in the permeate was less than 1.6mg·L^-1, and the oil rejection coefficient was always higher than 98.5% throughout the operation from the beginning.
基金Supported by the National Natural Science Foundation of China (20836006), the National Basic Research Program (2009CB623405), the Science & Technology Pillar Program of Tianjin (10ZCKFSH01700), the Programme of Introducing Talents of Discipline to Universities (B06006), and the Cheung Kong Scholar Program for Innovative Teams of the Ministry of Education (IRT0641).
文摘Fixed carrier membrane exhibits attractive CO2 permeance and selectivity due to its transport mechanism of reaction selectivity (facilitated transport). However, its performance needs improvement to meet cost targets for CO2 capture. This study attempts to develop membranes with multiple permselective mechanisms in order to enhance CO2 separation performance of fixed carder membrane. In this study, a novel membrane with multiplepermselective mechanisms of solubility selectivity and reaction selectivity was developed by incorporating CO2-selective adsorptive silica nanoparticles in situ into the tertiary amine containing polyamide membrane formed by interfacial polymerization (IP). Various techniques were employed to characterize the polyamide and polyam-ide-silica composite membranes. The TGA result shows that nanocomposite membranes exhlbit superior-thermal stability than pure polyamide membranes. In addition, gas permeation experiments show that both nanocomposite membranes have larger CO2 permeance than pure polyamide membranes. The enhanced CO2/N2 separation performance for nanocomposite membranes is mainly due to the thin film thickness, and multiple permselective mechanisms of solubility selectivity and reaction selectivity.
基金financially supported by the National Natural Science Foundation of China(No.20974094)National 973 Program(No.2009CB623402)Postdoctoral Science Foundation funded project of Zhejiang Province,China(Bsh1202045)
文摘A low operating pressure nanofiltration membrane is prepared by interfacial polymerization between m-phenylenediamine (MPDA) and trimesoyl chloride (TMC) using PVC hollow fiber membrane as supporting. A series of PVC nanofiltration membranes with different molecular weight cutoff (MWCO) can be obtained by controlling preparation conditions. Chemical and morphological characterization of the membrane surface was carried out by FTIR-ATR and SEM. MWCO was characterized by filtration experiments. The preparation conditions were investigated in detail. At the optimized conditions (40 min air-dried time, aqueous phase containing 0.5% MPDA, 0.05% SDS and 0.6% acid absorbent, oil phase containing 0.3% TMC, and 1 min reaction time), under 0.3 MPa, water flux of the gained nanofiltration membrane reaches 17.8 L/m2-h, and the rejection rates of methyl orange and MgSO4 are more than 90% and 60%, respectively.