The Experts below are selected from a list of 71550 Experts worldwide ranked by ideXlab platform
Jeffrey R Mccutcheon - One of the best experts on this subject based on the ideXlab platform.
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Braid-reinforced thin film Composite hollow fiber nanofiltration membranes
Journal of Membrane Science, 2019Co-Authors: Lingling Xia, Jian Ren, Jeffrey R MccutcheonAbstract:Abstract We report on a new thin film Composite (TFC) hollow fiber membrane that uses a braid-reinforced hollow fiber ultrafiltration membrane as a support. This reinforced support offers pressure tolerance that far exceeds self-supported hollow fiber membranes with the similar chemistry, morphology and geometry. A selective layer is formed onto this support using interfacial polymerization of piperazine (PIP) and trimesoyl chloride (TMC) monomers. Through a systematic optimization of monomer concentrations and reaction conditions, we have created membranes with MgSO4 rejection of 92% and a pure water permeance of 12 LMH/bar. Higher productivity membranes were made with pure water permeance of 22 LMH/bar and a MgSO4 rejection of 65%. The membranes also exhibited a low NaCl rejection (below 30%) which is desirable for water softening applications.
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pH Sensitivity of Ion Exchange through a Thin Film Composite Membrane in Forward Osmosis
Environmental Science and Technology Letters, 2015Co-Authors: Jason T. Arena, Holly A. Robillard, Malgorzata Chwatko, Jeffrey R MccutcheonAbstract:The uneven permeation of cations and anions through forward osmosis membranes offers a new technical challenge in the development of forward osmosis processes. Cation exchange in polyamide thin film Composite membranes is caused by carboxylic acid functional groups within the structure of these membranes’ selective layers. These functional groups will gain or lose a proton depending on the external solution pH. The deprotonation of a polyamide at alkaline pHs results in a net negative charge, allowing for the exchange of cations between feed and draw solutions having monovalent cations. In this study, the importance of solution pH in influencing cation transport across a commercial thin film Composite forward osmosis membrane was examined. It was found that cation transport across this membrane varies significantly with changes in pH and occurred fastest at alkaline pH.
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a new commercial thin film Composite membrane for forward osmosis
Desalination, 2014Co-Authors: Jeffrey R MccutcheonAbstract:Abstract New membranes for forward osmosis (FO) have been made by numerous academic groups around the world. Few of these designs, however, have made it to full-scale production. For two decades, the only FO membrane made on a full-scale production line was a cellulose acetate membrane from Hydration Technology Innovations (HTI). Only recently have other companies designed new membranes and produced them on a large scale, but those membranes are still largely unavailable to academic researchers. In this study, we report on a newly launched forward osmosis membrane from HTI. This thin film Composite (TFC) membrane is a departure from their cellulose acetate platform and is among if not the first TFC membrane to be made on a 40-inch line. The TFC membrane tested, which is their first generation TFC membrane, exhibited high water permeance and good mechanical strength relative to other membranes discussed in the academic literature. Under FO tests, the membrane achieved high water flux of 46.4 and 22.9 L m− 2 h− 1 with a modest salt flux of 24.9 and 6.4 g m− 2 h− 1 using 1 M sodium chloride against deionized water in pressure retarded osmosis (PRO) and FO modes, respectively.
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Nanofiber supported Thin-Film Composite membrane for pressure-retarded osmosis.
Environmental science & technology, 2014Co-Authors: Nhu-ngoc Bui, Jeffrey R MccutcheonAbstract:Sustainable energy can be harnessed from fluids of differing salinity using a process known as pressure-retarded osmosis (PRO). We address one of the critical challenges of advance PRO by introducing a novel electrospun nanofiber-supported Thin-Film Composite PRO membrane platform. The support was tiered with layers of nanofibers of different diameters to better withstand hydraulic pressure. The membranes successfully withstood an applied hydraulic pressure of 11.5 bar and exhibited performance that would produce an equivalent peak power density near 8.0 W/m(2) under real conditions (using 0.5 M NaCl and deionized water as the draw and feed solutions, respectively). This result shows the immense promise of nanofiber supported Thin-Film Composite membranes for use in PRO.
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novel hydrophilic nylon 6 6 microfiltration membrane supported thin film Composite membranes for engineered osmosis
Journal of Membrane Science, 2013Co-Authors: Liwei Huang, Mark T Meyering, Thomas J Hamlin, Jeffrey R MccutcheonAbstract:Abstract Previous investigations of engineered osmosis (EO) concluded that hydrophobic support layers of thin film Composite membrane causes severe internal concentration polarization due to incomplete wetting. Incomplete wetting reduces the effective porosity of the support, inhibiting mass transport and thus water flux. In this study, novel thin film Composite membranes were developed which consist of a poly(piperazinamide) or polyamide selective layer formed by interfacial polymerization on top of a nylon 6,6 microfiltration membrane support. This intrinsically hydrophilic support was used to increase the “wetted porosity” and to mitigate internal concentration polarization. Reverse osmosis tests showed that the permselectivity of our best poly(piperazinamide) and polyamide thin film Composite membranes approached those of a commercial nanofiltration and a commercial reverse osmosis membrane, respectively. The osmotic flux performance of the new polyamide thin film Composite membrane showed matched water flux, 10 fold lower salt flux and 8–28 fold lower specific salt flux than the standard commercial cellulose triacetate forward osmosis membrane from Hydration Technology Innovations™. The relatively good performance in osmotic flux tests of our thin film Composite membranes was directly related to the high permselectivity of the selective layers coupled with the hydrophilicity of the nylon 6,6 support. These results suggest that these nylon 6,6 supported thin film Composite membranes may enable applications like forward osmosis or pressure retarded osmosis.
Menachem Elimelech - One of the best experts on this subject based on the ideXlab platform.
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Zwitterionic coating on Thin-Film Composite membranes to delay gypsum scaling in reverse osmosis
Journal of Membrane Science, 2021Co-Authors: Humberto Jaramillo, Chanhee Boo, Sara M. Hashmi, Menachem ElimelechAbstract:Abstract Precipitation of calcium sulfate dihydrate (i.e., gypsum) on the membrane active layer negatively impacts the efficiency of reverse osmosis (RO) systems by increasing overall operation and maintenance costs. The interfacial free energy between RO membranes and scalants is expected to play a paramount role in crystal nucleation and adsorption. In this work, we modified the surface of a Thin-Film Composite RO membrane with a zwitterionic polymer brush via atom transfer radical polymerization (ATRP) to impart superhydrophilicity for enhanced resistance to gypsum scaling. The zwitterionic polymer coating was optimized and a highly hydrophilic membrane surface displaying a water contact angle of
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Thin-Film Composite forward osmosis membranes functionalized with graphene oxide–silver nanoComposites for biofouling control
Journal of Membrane Science, 2017Co-Authors: Andreia F. Faria, Long Duc Nghiem, François Perreault, Jun Ma, Caihong Liu, Ming Xie, Menachem ElimelechAbstract:Innovative approaches to prevent bacterial attachment and biofilm growth on membranes are critically needed to avoid decreasing membrane performance due to biofouling. In this study, we propose the fabrication of anti-biofouling Thin-Film Composite membranes functionalized with graphene oxide–silver nanoComposites. In our membrane modification strategy, carboxyl groups on the graphene oxide–silver nanosheets are covalently bonded to carboxyl groups on the surface of Thin-Film Composite membranes via a crosslinking reaction. Further characterization, such as scanning electron microscopy and Raman spectroscopy, revealed the immobilization of graphene oxide–silver nanoComposites on the membrane surface. Graphene oxide–silver modified membranes exhibited an 80% inactivation rate against attached Pseudomonas aeruginosa cells. In addition to a static antimicrobial assay, our study also provided insights on the anti-biofouling property of forward osmosis membranes during dynamic operation in a cross-flow test cell. Functionalization with graphene oxide–silver nanoComposites resulted in a promising anti-biofouling property without sacrificing the membrane intrinsic transport properties. Our results demonstrated that the use of graphene oxide–silver nanoComposites is a feasible and attractive approach for the development of anti-biofouling Thin-Film Composite membranes.
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biofouling mitigation in forward osmosis using graphene oxide functionalized thin film Composite membranes
Environmental Science & Technology, 2016Co-Authors: François Perreault, Mercy Ude, Long Duc Nghiem, Humberto Jaramillo, Menachem Elimelech, Ming XieAbstract:Forward osmosis (FO) is an emerging membrane process with potential applications in the treatment of highly fouling feedwaters. However, biofouling, the adhesion of microorganisms to the membrane and the subsequent formation of biofilms, remains a major limitation since antifouling membrane modifications offer limited protection against biofouling. In this study, we evaluated the use of graphene oxide (GO) for biofouling mitigation in FO. GO functionalization of Thin-Film Composite membranes (GO-TFC) increased the surface hydrophilicity and imparted antimicrobial activity to the membrane without altering its transport properties. After 1 h of contact time, deposition and viability of Pseudomonas aeruginosa cells on GO-TFC were reduced by 36% and 30%, respectively, compared to pristine membranes. When GO-TFC membranes were tested for treatment of an artificial secondary wastewater supplemented with P. aeruginosa, membrane biofouling was reduced by 50% after 24 h of operation. This biofouling resistance is ...
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surface functionalization of thin film Composite membranes with copper nanoparticles for antimicrobial surface properties
Environmental Science & Technology, 2014Co-Authors: Moshe Bensasson, Katherine R Zodrow, Qi Genggeng, Yan Kang, Emmanuel P Giannelis, Menachem ElimelechAbstract:Biofouling is a major operational challenge in reverse osmosis (RO) desalination, motivating a search for improved biofouling control strategies. Copper, long known for its antibacterial activity and relatively low cost, is an attractive potential biocidal agent. In this paper, we present a method for loading copper nanoparticles (Cu-NPs) on the surface of a Thin-Film Composite (TFC) polyamide RO membrane. Cu-NPs were synthesized using polyethyleneimine (PEI) as a capping agent, resulting in particles with an average radius of 34 nm and a copper content between 39 and 49 wt.%. The positive charge of the Cu-NPs imparted by the PEI allowed a simple electrostatic functionalization of the negatively charged RO membrane. We confirmed functionalization and irreversible binding of the Cu-NPs to the membrane surface with SEM and XPS after exposing the membrane to bath sonication. We also demonstrated that Cu-NP functionalization can be repeated after the Cu-NPs dissolve from the membrane surface. The Cu-NP functi...
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Superhydrophilic Thin-Film Composite Forward Osmosis Membranes for Organic Fouling Control: Fouling Behavior and Antifouling Mechanisms
Environmental science & technology, 2012Co-Authors: Alberto Tiraferri, Yan Kang, Emmanuel P Giannelis, Menachem ElimelechAbstract:This study investigates the fouling behavior and fouling resistance of superhydrophilic Thin-Film Composite forward osmosis membranes functionalized with surface-tailored nanoparticles. Fouling experiments in both forward osmosis and reverse osmosis modes are performed with three model organic foulants: alginate, bovine serum albumin, and Suwannee river natural organic matter. A solution comprising monovalent and divalent salts is employed to simulate the solution chemistry of typical wastewater effluents. Reduced fouling is consistently observed for the superhydrophilic membranes compared to control Thin-Film Composite polyamide membranes, in both reverse and forward osmosis modes. The fouling resistance and cleaning efficiency of the functionalized membranes is particularly outstanding in forward osmosis mode where the driving force for water flux is an osmotic pressure difference. To understand the mechanism of fouling, the intermolecular interactions between the foulants and the membrane surface are analyzed by direct force measurement using atomic force microscopy. Lower adhesion forces are observed for the superhydrophilic membranes compared to the control Thin-Film Composite polyamide membranes. The magnitude and distribution of adhesion forces for the different membrane surfaces suggest that the antifouling properties of the superhydrophilic membranes originate from the barrier provided by the tightly bound hydration layer at their surface, as well as from the neutralization of the native carboxyl groups of Thin-Film Composite polyamide membranes.
Hyung Keun Lee - One of the best experts on this subject based on the ideXlab platform.
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Highly selective thin film Composite hollow fiber membranes for mixed vapor/gas separation
RSC Advances, 2015Co-Authors: Pravin G. Ingole, Won Kil Choi, Il-hyun Baek, Hyung Keun LeeAbstract:In the present study, thin film Composite membranes have been prepared using an interfacial polymerization method.
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Synthesis of cross-linked amides and esters as thin film Composite membrane materials yields permeable and selective material for water vapor/gas separation
Journal of Materials Chemistry A, 2015Co-Authors: Sang Hee Yun, Pravin G. Ingole, Won Kil Choi, Jong Hak Kim, Hyung Keun LeeAbstract:In this work, 3,5-diaminobenzoic acid (BA) was selected to synthesize polyamide as a selective layer because it is considered desirable to fabricate hydrophilic thin film Composite (TFC) membranes for water vapor separation.
Mohtada Sadrzadeh - One of the best experts on this subject based on the ideXlab platform.
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Thermally stable thin film Composite polymeric membranes for water treatment: A review
Journal of Cleaner Production, 2020Co-Authors: Pooria Karami, Behnam Khorshidi, Mick Mcgregor, John T. Peichel, João B. P. Soares, Mohtada SadrzadehAbstract:Abstract Demand for hot water treatment has opened up broad new areas of research for fabricating thermally stable polymer membranes. In multiple industrial applications, the contaminated process water must be treated at high temperatures to maintain a sustainable and energy-efficient water recycling process. The present article reviews recent efforts made to develop thermally stable thin film Composite membranes and provides insights on polymer material selection rationale, characterization techniques, promising progresses, major challenges, and potential future trends. Thin film Composite membranes are the most commonly used polymeric membranes for desalination and water treatment, primarily due to their outstanding permeation properties. However, commercially available thin film Composite membranes suffer from limited thermal resilience at temperatures above 45 °C, resulting in a short working lifetime. This limitation has motivated researchers to improve the thermal stability of thin film Composite membranes through three primary approaches: (i) tuning the chemistry of the selective layer, (ii) enhancing the thermal properties of the porous sublayer, and (iii) incorporating nanomaterials into both the selective and support layers of thin film nanoComposite membranes. Among different approaches, efforts on modifying the selective layer have gained momentum due to the critical role it plays on the overall separation performance. Synthesis parameters were modified to develop new polyamide layers with higher cross-linking degree and rigidity. Furthermore, employing other strategies, such as using novel sublayers or well-dispersed nanoparticles was also found to increase the thermal tolerance of thin film Composite membranes. The major challenges for the development of robust thin film Composite and nanoComposite membranes are yet to: (i) overcome the trade-off relation between thermal stability and permselectivity of membranes, primarily caused by low reactivity of new monomers with stabilized resonance structure and severe aggregation of nanoparticles, and (ii) explore reliable methods to characterize the individual layers of Composite membranes. This review explains how to select appropriate materials and preparation methods to produce thermally stable thin film Composite membranes. The possible future directions of research in this field also discussed.
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Fabrication of Highly Permeable and Thermally Stable Reverse Osmosis Thin Film Composite Polyamide Membranes
ACS applied materials & interfaces, 2019Co-Authors: Pooria Karami, Behnam Khorshidi, João B. P. Soares, Mohtada SadrzadehAbstract:Developing thermally stable polymer membranes for high-temperature water treatment is in high demand, as the recommended usage temperatures of most commercial membranes are lower than 50 °C. In this study, we synthesized novel thin film Composite polyamide membranes by modifying the chemical structure of their selective layers. Triaminopyrimidine was used to synthesize a polyamide selective layer with high cross-linking density over a microporous poly(ether sulfone) support. The addition of triamiopyrimidine to the classic m-phenylenediamine/trimesoyl chloride combination remarkably improved the permeation of the membranes. All synthesized thin film Composite membranes showed consistent permeate flux for 9 h of operation at 75 °C with only a slight reduction in salt rejection. This study provides a promising and reproducible methodology to develop thermally stable high-flux thin film Composite membranes, opening up a new paradigm for high-temperature water treatment processes.
Bart Van Der Bruggen - One of the best experts on this subject based on the ideXlab platform.
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Nano/microstructure decorated thin film Composite poly (arylene sulfide sulfone) membrane constructed by induced fouling in organic solvent ultrafiltration
Chemical Engineering Journal, 2018Co-Authors: Shushan Yuan, Junyong Zhu, Alexander Volodine, Jie Yang, Peter Van Puyvelde, Bart Van Der BruggenAbstract:Abstract In this study, novel thin film Composite membranes with nano/macrostructure decorated surface were fabricated by deposition of poly (arylene sulfide sulfone) (PASS) polymer chains on oxidized poly (arylene sulfide sulfone) (O-PASS) support membrane during organic solvent ultrafiltration. Interestingly, the obtained membranes exhibited a rough surface structure composed of ordered arranged polymeric nodules with size ranging from nanoscale (100 nm) to macroscale (5 μm). Additionally, these membranes showed an improved, ultrahigh rejection of direct red 23, reactive blue 2, demonstrating their potential application for the reuse of dyes in wastewater. Furthermore, this novel synthesis approach of thin film Composite membranes has great advantages in incorporating nanoparticles because of the facile process, the low consumption of nanoparticles and the high content of nanoparticles in the thin layer. During the whole thin layer synthesis process, only 2 mg of nanoparticles were used and thin layers with nanoparticles content of 20% were obtained. After the incorporation of candle soot, SiO2 and ZIF-8 in the separation layer, both the water permeation and rejection of direct red 23, reactive blue 2 and reactive orange 16 were greatly improved. Therefore, this study provides a novel and simple fabrication method for thin film Composite membranes, which has advantages in incorporating nanoparticles in the thin separation layer to endow the membrane with an improved performance.
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Novel binding procedure of TiO2 nanoparticles to thin film Composite membranes via self-polymerized polydopamine
Journal of Membrane Science, 2013Co-Authors: Ruixin Zhang, Leen Braeken, Patricia Luis, Xiaolin Wang, Bart Van Der BruggenAbstract:This study presents a novel and versatile approach to robustly bind TiO2 nanoparticles on thin film Composite (TFC) membranes by using polydopamine, which is capable to self-polymerize on membranes as well as on the surfaces of nanoparticles. The traditional self-assembly method is used as a reference. The binding performance of both methods is investigated by rinsing and wiping tests and evaluated by scanning electronic microscopy (SEM). In addition, the effects of the concentration of TiO2 nanoparticles in the suspension as well as the polymerization time of dopamine on the binding performance are studied. It was observed that, for the same modification and rinsing conditions, the polydopamine method is able to bind significantly more TiO2 on the membrane surface. According to the wiping test, the quantity of nanoparticles embedded in the polydopamine layer does not change. However, the traditional self-assembly method cannot stand the wiping force and no nanoparticles are left after wiping. The interesting hydrophilicity and the filtration performance of each modification step is further investigated. The polydopamine significantly increases the water contact angle of the polyamide thin film Composite (TFC) membranes. The membranes modified by the traditional self-assembly method exhibit a significant flux loss compared to the original membranes. On the contrary, the polydopamine method can keep the membrane performance. Thus, this procedure can be considered as a novel and versatile method to bind TiO2 nanoparticles on TFC membranes, and it can be easily adapted for a variety of membranes to bind nanomaterials without a complex surface pretreatment
