A novel matrix of macropore cellulose membrane was prepared by chemical graft, and immobilized the cationic charged groups as affinity ligands. The prepared membrane Fan be used for the removal of endotoxin from human...A novel matrix of macropore cellulose membrane was prepared by chemical graft, and immobilized the cationic charged groups as affinity ligands. The prepared membrane Fan be used for the removal of endotoxin from human serum albumin (HSA) solutions. With a cartridge of 20 sheets affinity membrane of 47 mm diameter, the endotoxin level in HSA solution can be reduced ro 0.027 eu/mL. Recovery of HSA was over 95%.展开更多
Ionic partition equilibrium on a charged membrane immersed in a mixed electrolyte solution was systematically investigated and several models were established for the determination of partition coefficients. On the ba...Ionic partition equilibrium on a charged membrane immersed in a mixed electrolyte solution was systematically investigated and several models were established for the determination of partition coefficients. On the basis of theoretical models, the effects of the concentration ratio λ of the fixed group(charged density) to reference electrolyte, the concentration ratio η between the two electrolytes existing in the solution and the valence of the electrolyte ions on the partition equilibrium in a positively charged membrane were analyzed and simulated within the chosen parameters in detail. The obtainable results can also be applicable to a sytem of mixed electrolytes contacting with a negatively charged membrane. The theoretical calculations were confirmed with the experimental data of model mixed electrolytes, NaCl+HCl and CaCl 2+NaCl partitioned in the system of self made negatively charged membrane sulphonated poly(phenylene oxide)(SPPO) with different charge densities.展开更多
A selfmade positively charged nanofiltration (NF) membrane was used to treat textile dye effluent to generate water for reuse, and the factors affecting nanofiltration process such as operating pressure, feed flow a...A selfmade positively charged nanofiltration (NF) membrane was used to treat textile dye effluent to generate water for reuse, and the factors affecting nanofiltration process such as operating pressure, feed flow and membrane cleaning were investigated. With an applied pressure of 1.0 MPa and a feed flow of 40 L/h, this NF membrane has a removal of 93.3% for CODor and a reduction of approximately 51.0% in TDS, salinity and conductivity achieving the chroma removal of 100%. The permeate obtained through this membrane is suitable for recycling. Moreover, the membrane could be reused after being cleaned with 1% NaOH solution.展开更多
Positively charged composite nanofiltration (NF) membranes were prepared through interfacial polymerization of poly[2-(N,N-dimethyl amino)ethyl methacrylate](PDMAEMA) on porous polysulfone (PSF) substrate memb...Positively charged composite nanofiltration (NF) membranes were prepared through interfacial polymerization of poly[2-(N,N-dimethyl amino)ethyl methacrylate](PDMAEMA) on porous polysulfone (PSF) substrate membranes. The effects of pH on swelling ratio (SR) of the pure crosslinked PDMAEMA membrane and on separation performances of the composite NF membrane were investigated. The results show that the quaternized amino groups produced through interfacial polymerization technique are soluble in both phases, which accelerate the crosslinking reaction as self-catalysts. The swelling/contracting behavior of the pure crosslinked PDMAEMA exhibited a well reversible pH sensitive property. Importantly, the rejection and flux of the composite NF membrane show pH-sensitive behavior in NF process. Furthermore, with the help of a relatively novel method to measure membrane conduction, the true zeta potentials calculated on the basis of the streaming potential measurements proved the pH-sensitive behavior of the NF membrane.展开更多
To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane.The internal surface of the highly por...To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane.The internal surface of the highly porous ceramic membrane was coated with uniformly distributed electropositive nano-Y2O3 coating. The dye removal performance was evaluated through pressurized filtration tests using Titan Yellow aqueous solution. It showed that positively charged microporous ceramic membrane exhibited a flow rate of 421 L/(m^2·hr) under the trans-membrane pressure of 0.03 bar. Moreover it could effectively remove Titan Yellow with feed concentration of 10 mg/L between pH 3 to 8. The removal rate increased with the enhancement of the surface charge properties with a maximum rejection of 99.6%. This study provides a new and feasible method of removing organic dyes in wastewater. It is convinced that there will be a broad market for the application of charged ceramic membrane in the field of dye removal or recovery from industry wastewater.展开更多
A series of amphiphilic copolymers containing poly(vinyl chloride-r-acrylic acid) (P(VC-r-AA)) was synthesized and used to prepare membranes via a non-solvent induced phase separation method. The prepared membra...A series of amphiphilic copolymers containing poly(vinyl chloride-r-acrylic acid) (P(VC-r-AA)) was synthesized and used to prepare membranes via a non-solvent induced phase separation method. The prepared membranes were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and water contact angle and zeta potential measurements. The copolymer P(VC-r-AA) chains did not dissolved in a coagulation bath, indicating that the AA segments were completely retained within the membrane. Enriching degree of AA segments in surface layer was 2 for copolymer membrane. In addition, the introduction of AA segments made the membrane electronegative and hydrophilic so that the membrane was sensitive to the solution pH. The fouling resistance, adsorption of Cu(II), Cr(III) and Ce(IV) ions and the desorption properties of the membranes were also determined. The copolymer membranes exhibited good antifouling performance with a fouling reversibility of 92%. The membranes also had good adsorption capacities for Cu(II), Cr(III) and Ce(IV) ions. The optimal pH for Cu(II) adsorption was 6 and the copolymer membrane has potential applications for low concentration Cu(II) removal.展开更多
文摘A novel matrix of macropore cellulose membrane was prepared by chemical graft, and immobilized the cationic charged groups as affinity ligands. The prepared membrane Fan be used for the removal of endotoxin from human serum albumin (HSA) solutions. With a cartridge of 20 sheets affinity membrane of 47 mm diameter, the endotoxin level in HSA solution can be reduced ro 0.027 eu/mL. Recovery of HSA was over 95%.
基金Supported by the National Natural Science Foundation of China(No.2 0 10 6 0 15 and2 9976 0 4 0 ) Natural Science Foun-dation of Anhui Province(No.990 4 5 4 31) and Key Foundation of Educational Comm ittee of Anhui Province(No.2 0 0 0 jl2 5 5 zd)
文摘Ionic partition equilibrium on a charged membrane immersed in a mixed electrolyte solution was systematically investigated and several models were established for the determination of partition coefficients. On the basis of theoretical models, the effects of the concentration ratio λ of the fixed group(charged density) to reference electrolyte, the concentration ratio η between the two electrolytes existing in the solution and the valence of the electrolyte ions on the partition equilibrium in a positively charged membrane were analyzed and simulated within the chosen parameters in detail. The obtainable results can also be applicable to a sytem of mixed electrolytes contacting with a negatively charged membrane. The theoretical calculations were confirmed with the experimental data of model mixed electrolytes, NaCl+HCl and CaCl 2+NaCl partitioned in the system of self made negatively charged membrane sulphonated poly(phenylene oxide)(SPPO) with different charge densities.
基金Funded by the Major State Basic Research Development Program of China (973 Program)( No.2003CB615706)
文摘A selfmade positively charged nanofiltration (NF) membrane was used to treat textile dye effluent to generate water for reuse, and the factors affecting nanofiltration process such as operating pressure, feed flow and membrane cleaning were investigated. With an applied pressure of 1.0 MPa and a feed flow of 40 L/h, this NF membrane has a removal of 93.3% for CODor and a reduction of approximately 51.0% in TDS, salinity and conductivity achieving the chroma removal of 100%. The permeate obtained through this membrane is suitable for recycling. Moreover, the membrane could be reused after being cleaned with 1% NaOH solution.
基金Funded by the National Natural Science Foundation of China (No.50673077)National Basic Research Program of China (No.2006CB708602)
文摘Positively charged composite nanofiltration (NF) membranes were prepared through interfacial polymerization of poly[2-(N,N-dimethyl amino)ethyl methacrylate](PDMAEMA) on porous polysulfone (PSF) substrate membranes. The effects of pH on swelling ratio (SR) of the pure crosslinked PDMAEMA membrane and on separation performances of the composite NF membrane were investigated. The results show that the quaternized amino groups produced through interfacial polymerization technique are soluble in both phases, which accelerate the crosslinking reaction as self-catalysts. The swelling/contracting behavior of the pure crosslinked PDMAEMA exhibited a well reversible pH sensitive property. Importantly, the rejection and flux of the composite NF membrane show pH-sensitive behavior in NF process. Furthermore, with the help of a relatively novel method to measure membrane conduction, the true zeta potentials calculated on the basis of the streaming potential measurements proved the pH-sensitive behavior of the NF membrane.
基金supported by the National Natural Science Foundation of China (No. 51202292)
文摘To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane.The internal surface of the highly porous ceramic membrane was coated with uniformly distributed electropositive nano-Y2O3 coating. The dye removal performance was evaluated through pressurized filtration tests using Titan Yellow aqueous solution. It showed that positively charged microporous ceramic membrane exhibited a flow rate of 421 L/(m^2·hr) under the trans-membrane pressure of 0.03 bar. Moreover it could effectively remove Titan Yellow with feed concentration of 10 mg/L between pH 3 to 8. The removal rate increased with the enhancement of the surface charge properties with a maximum rejection of 99.6%. This study provides a new and feasible method of removing organic dyes in wastewater. It is convinced that there will be a broad market for the application of charged ceramic membrane in the field of dye removal or recovery from industry wastewater.
基金This research was supported by the National High Technology Research and Development Program of China (Granted No. 2012AA03A602 ) , the National Basic Research Program of China (Granted No. 2009CB623402) and the National Natural Science Foundation of China (Grant No. 20974094).
文摘A series of amphiphilic copolymers containing poly(vinyl chloride-r-acrylic acid) (P(VC-r-AA)) was synthesized and used to prepare membranes via a non-solvent induced phase separation method. The prepared membranes were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and water contact angle and zeta potential measurements. The copolymer P(VC-r-AA) chains did not dissolved in a coagulation bath, indicating that the AA segments were completely retained within the membrane. Enriching degree of AA segments in surface layer was 2 for copolymer membrane. In addition, the introduction of AA segments made the membrane electronegative and hydrophilic so that the membrane was sensitive to the solution pH. The fouling resistance, adsorption of Cu(II), Cr(III) and Ce(IV) ions and the desorption properties of the membranes were also determined. The copolymer membranes exhibited good antifouling performance with a fouling reversibility of 92%. The membranes also had good adsorption capacities for Cu(II), Cr(III) and Ce(IV) ions. The optimal pH for Cu(II) adsorption was 6 and the copolymer membrane has potential applications for low concentration Cu(II) removal.