Thin-Film Composite (TFC)

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Thin Film Composite and/or Thin Film Nanocomposite Hollow Fiber Membrane for Water Treatment, Pervaporation and Gas/Vapor Separation

Thin Film Composite and/or Thin Film Nanocomposite Hollow Fiber Membrane for Water Treatment, Pervaporation and Gas/Vapor Separation

PRO can be viewed as an intermediate process between FO and RO, where hydraulic pressure is applied in the opposite direction of the osmotic pressure gradient (similar to RO). Loeb and Norman [36] proposed pressure-retarded osmosis (PRO) process. In a PRO process, water flows naturally from a low salinity stream (feed water) at an ambient pressure across a semi-permeable membrane to a pressurized high salinity stream (draw solution) driven by the osmotic pressure difference across the membrane. Chou et al. [37] first time reported the fabrication of thin-film composite hollow fiber membranes which could be used in PRO process. Composite hollow fiber membrane was prepared by depositing a thin layer of PA on PES hollow fiber via IP. The main reagents used were m-phenylenediamine (MPD), trimesoyl chloride (TMC) and cyclohexane. From the performance test, it was revealed that The TFC PRO hollow fiber membranes have a water permeability (A) of 9.22 × 10 −12 m/(s Pa), salt permeability (B) of 3.86 × 10 −8 m/s and structural
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Plasma-induced physicochemical effects on a poly(amide) thin-film composite membrane

Plasma-induced physicochemical effects on a poly(amide) thin-film composite membrane

50. Kim, S.H., S.-Y. Kwak, and T. Suzuki, Positron Annihilation Spectroscopic Evidence to Demonstrate the Flux-Enhancement Mechanism in Morphology-Controlled Thin- Film-Composite (TFC) Membrane. Environmental Science & Technology, 2005. 39(6): p. 1764-1770.

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Preparation of Novel Thin-Film Composite Nanofiltration Membranes for Separation of Amoxicillin

Preparation of Novel Thin-Film Composite Nanofiltration Membranes for Separation of Amoxicillin

Nanofiltration (NF) membranes, which exhibit separation characteristics in the intermediate range between reverse osmosis and ultrafiltration membranes, are gaining interest worldwide because of advantages such as low operation pressure, high permeate flux and high retention of multivalent ion salts [9-11]. NF process has been used in many applications such as wastewater reclamation [12-13], industrial water production, water softening [14-15] and the separation of compounds having different molecular weights [16-17]. Most NF membranes developed to date have a thin-film composite (TFC) structure due to key advantages compared to asymmetric membranes [18-21]. In a TFC membrane, the support layer provides an appropriate mechanical strength with low resistance to permeate flow and
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Zwitterion Embedded Thin Film Composite Membrane for Oily Wastewater Treatment

Zwitterion Embedded Thin Film Composite Membrane for Oily Wastewater Treatment

Recent development in oil and gas industry increases the production and consumption of oil. The enormous amount of oily wastewater produced is urged to be treated, in order to prevent humanity and environment from being threatened. Membrane technology is an appealing alternative for oily wastewater treatment due to its design simplicity, energy efficiency and gentle environmental approach. In this study, a poly[3-(N-2-methacryloylxyethyl-N,N-dimethyl)- ammonatopropanesulfonate] (PMAPS) incorporated thin film composite (TFC) membrane with excellent anti-fouling properties was fabricated for oil removal from oily wastewater through forward osmosis process. PMAPS was blended with the polyethersulfone (PES) dope solution and casted into PES support layer. The TFC was fabricated via interfacial polymerization (IP) technique to form a thin film polyamide (PA) layer a top of a PES support layer. The PMAPS incorporated TFC membranes has been characterized for their morphology, surface hydrophilicity and charges. The incorporation of PMAPS was compatible with the PES polymer matrix hence lead to defect-free thin film formation. Prior to the hydrophilicity of PMAPS, the resultant 1% PMAPS-TFC membrane exhibited a high water flux of 15.12±0.3 L/m 2 .h and oil flux <0.1±0.08 g/m 2 .h, reverse salt flux of 3.93±0.4 L/m 2 .h under
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The effect of curing temperature on the performance of thin film composite membrane

The effect of curing temperature on the performance of thin film composite membrane

The development of asymmetric membranes dates back to the early 1960s when Loeb and Sourirajan [2], working with a cellulose acetate (CA) membrane at University of California in Los Angeles (UCLA), noticed that the membrane had a rough and a smooth side. They found that when the rough side faced the feed, the rejection was low, but when the smooth side faced the feed, the rejection was high. This anisotropic property of the membrane led to the term “asymmetric” membrane. Recently, the asymmetric membranes are commercially available in the form of cellulose acetate, cellulose diacetate and triacetate grades or in blends of these grades. The asymmetric cellulose acetate membranes are resistant to chlorine in the feed up to 1 mgl -1 , but are subjected to hydrolysis at high pH. Blends of cellulose acetate and triacetate provide superior performance and higher rejection. Although asymmetric cellulose acetate technology predates other membrane types and remains relatively inexpensive to purchase and install, thin film composite membranes largely displace today’s use of cellulose acetate.
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Towards Enhanced Performance Thin-film Composite Membranes via Surface Plasma Modification

Towards Enhanced Performance Thin-film Composite Membranes via Surface Plasma Modification

Advancing the design of thin-film composite membrane surfaces is one of the most promising pathways to deal with treating varying water qualities and increase their long-term stability and permeability. Although plasma technologies have been explored for surface modification of bulk micro and ultrafiltration membrane materials, the modification of thin film composite membranes is yet to be systematically investigated. Here, the performance of commercial thin-film composite desalination membranes has been significantly enhanced by rapid and facile, low pressure, argon plasma activation. Pressure driven water desalination tests showed that at low power density, flux was improved by 22% without compromising salt rejection. Various plasma durations and excitation powers have been systematically evaluated to assess the impact of plasma glow reactions on the physico-chemical properties of these materials associated with permeability. With increasing power density, plasma treatment enhanced the hydrophilicity of the surfaces, where water contact angles decreasing by 70% were strongly correlated with increased negative charge and smooth uniform surface morphology. These results highlight a versatile chemical modification technique for post-treatment of commercial membrane products that provides uniform morphology and chemically altered surface properties.
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Charge tunable thin-film composite membranes by gamma-ray triggered surface polymerization

Charge tunable thin-film composite membranes by gamma-ray triggered surface polymerization

Thin-film composite poly(amide) (PA) membranes have greatly diversified water supplies and food products. However, users would benefit from a control of the electrostatic interactions between the liquid and the net surface charge interface in order to benefit wider application. The ionic selectivity of the 100 nm PA semi-permeable layer is significantly affected by the pH of the solution. In this work, for the first time, a convenient route is presented to configure the surface charge of PA membranes by gamma ray induced surface grafting. This rapid and up-scalable method offers a versatile route for surface grafting by adjusting the irradiation total dose and the monomer concentration. Specifically, thin coatings obtained at low irradiation doses between 1 and 10 kGy and at low monomer concentration of 1 v/v% in methanol/water (1:1) solutions, dramatically altered the net surface charge of the pristine membranes from −25 mV to +45 mV, whilst the isoelectric point of the materials shifted from pH 3 to pH 7. This modification resulted in an improved water flux by over 55%, from 45.9 to up 70 L.m −2 .h −1 , whilst NaCl rejection was found to drop by only 1% compared to pristine membranes.
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Fabrication and Modification of Thin-Film Composite Hollow Fiber NF Membranes

Fabrication and Modification of Thin-Film Composite Hollow Fiber NF Membranes

Thin-film composite hollow fiber membranes were prepared by interfacial polymerization of Piperazine in aqueous phase with TMC in organic phase (i.e. n-hexane). The concentration of additives in the aqueous phase are given in Table 2. The PSF hollow fiber support membrane was submerged into the aqueous phase for 90 s. Subsequently, the membrane was taken out to drain off the excess monomers for 1 min. The amine saturated membrane was again immersed into the organic phase containing 0.5% (w/v) TMC in n-hexane where the conventional IP reaction took place. Afterward, the membrane was taken out and air-dried at 70 °C for 4 min. The dipping process had been carried out such a way that only the external surface has come in contact with reactants to form polyamide skin layer.
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Formation of thin film composite nanofiltration membrane: Effect of polysulfone substrate characteristics

Formation of thin film composite nanofiltration membrane: Effect of polysulfone substrate characteristics

In this work, polysulfone (PSf) substrates with different properties were made by varying the polymer con- centration in the dope solution in the range 12 – 20 wt.%. Polyamide (PA) thin layers were then formed via interfacial polymerization between piperazine and trimethylchloride over the PSf substrates. Both top PA thin layers and bottom PSf substrates were characterized with respect to physicochemical properties, structural morphology, and water fl ux/salt rejection to investigate the in fl uence of substrate properties on the characteristics of PA thin layers. Physical properties of the PA layers were reported to be altered using different PSf substrate properties and were in good agreement with the change in water flux. From the FESEM pictures, it is found that the thickness of PA layer increased as the surface pore size of sup- port membrane decreased. The change in the membrane structural properties in particular pore size is found to portray significant contribution to the changes of formed PA layer. Interestingly, only slight changes on Na 2 SO 4 and MgSO 4 salt rejection were reported on any TFC membranes. Considering both
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A recent progress in thin film composite membrane: A review

A recent progress in thin film composite membrane: A review

The concept of interfacial polymerization has been known for more than 45 years since it was fi rst introduced by Mogan in 1965. Through this concept, an ultrathin selective layer formed by interfacial cross-linking between reactive monomers could be easily established upon a porous supporting membrane, leading to excellent selectivity to divalent ion without sacri fi cing water productivity. Currently, the use of TFC membranes is found dominating the applications of NF and RO and has showed huge potential to be further used in applications involving gas separation, pervaporation, hydrocarbon fractionations, etc. It is too early to conclude that this technology has already reached the maturity while many opportunities still exist. Efforts should continue on the development of high fl ux/low pressure composite membrane with enhanced salt rejection as well as improved resistances of fouling, chlorine, solvent, etc. More attention should be paid on the interaction between PA top active layer and underlying supporting membrane. This area deserves intensive studies as no one has conducted comprehensive investigation to describe what kind of idealized substrate surface properties (e.g. pore dimension, surface roughness, hydrophilicity, porosity, etc.) could match perfectly with interfacially synthesized PA layer. Also, development of a strong adhesion between active layer and support is of practical importance to overcome the swelling problem which might limit the operations of composite membranes to certain applications. Continuous improve- ments in TFC membrane performances with respect to permeability, selectivity and stability perhaps in the future will widen the applications of membranes to new areas.
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A Thiocyanate Sensor Based On Ecofriendly Silver Nanoparticles Thin Film Composite

A Thiocyanate Sensor Based On Ecofriendly Silver Nanoparticles Thin Film Composite

Further the application of nanoparticles was studied on the aqueous thiocyanate sensing properties of CS/AgNPs thin film. The silver nano particles dispersion in polymer matrix played a more important role in colorimetric sensing applications. Colorimetric assays based on the unique LSPR properties of metallic nanoparticles have showed to be very useful due to their simplicity, high sensitivity, low detection limit of 1 ppm, low cost, fast response time and great reproducibility. Keeping these significance properties in mind, in the near future we can use our room temperature optical thiocyanate sensor for clinical and medical diagnosis for detecting low thiocyanate level in human.
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Dopamine Incorporated Forward Osmosis Membranes with High Structural Stability and Chlorine Resistance

Dopamine Incorporated Forward Osmosis Membranes with High Structural Stability and Chlorine Resistance

Abstract: The degradation and detachment of the polyamide (PA) layer in thin-film composite (TFC) membranes due to chlorine based chemical cleaning and material difference of PA layer and substrate are two major bottlenecks of forward osmosis (FO) technology. In this study, a new type of FO membranes were prepared by controlling self-polymerization of dopamine (DA) in the aqueous phase and the reaction with trimesoyl chloride (TMC) during interfacial polymerization (IP) process. These membranes were characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FESEM) and water contact angle measurements. The influence of synthesis parameters such as pH of the aqueous phase, reaction time, temperature, and monomer concentrations were systematically investigated. The optimized membrane showed enhanced structure stability in ethanol (7.1 times higher) and chlorine resistance (72.3 times higher) than the conventional Piperazine(PIP)/TMC membrane due to ( poly-dopamine ) PDA bio-adhesion and polyester groups in the membrane structure. In general, DA/TMC membranes could be an effective strategy to fabricate high-performance FO membranes with excellent structural stability and chlorine resistance.
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Effect of change in trans-membrane pressure differences on the efficiency of a thin film reverse osmosis membrane.

Effect of change in trans-membrane pressure differences on the efficiency of a thin film reverse osmosis membrane.

Abstract : A spiral wound thin film composite reverse osmosis membrane was tested for its efficiency for the removal of certain water contaminants and its efficiency in terms of permeate generation. The experiment was performed using solutions of known concentrations of the contaminants at two trans membrane pressure differences. The synthetic solution concentrations used exceeded the permissible limits i.e., 100ppm of nitrate, 10ppm of fluoride, 1000ppm of chloride, 30ppm of iron, 25ppm of chromium, 5ppm of cadmium, and 25ppm of copper. The efficiency of membrane towards the removal of different contaminant from the feed solutions ranged from 88.8 to 99.8%. The contaminant concentrations in permeate were well below the standard limits for drinking water. The efficiency of permeate generation was low. However the efficiency of permeate generation increased at higher trans membrane pressure difference with no decline in removal efficiency of the contaminants, rather it improved. The type of the contaminants did not have a significant difference on the permeate recovery.
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Development of MoS2 CNT composite thin film from layered MoS2 for lithium batteries

Development of MoS2 CNT composite thin film from layered MoS2 for lithium batteries

In this work, SWNT was combined with the intrinsically con- ductive surfactant, PEDOT:PSS, to create organic thermoelec- tric thin films. PEDOT:PSS has been previously shown to effectively disperse carbon nanotubes (CNTs) in an aqueous solution and increase the electrical conductivity of the mixture as a whole. 19,32 Figure 1(a) depicts an exfoliated solution of CNT with PEDOT:PSS attached to its surface. The surfactant helps prevent the hydrophobic CNT from aggre- gating together through enhanced hydrophilicity. As the solu- tion is allowed to dry, electrically conductive junctions form between CNT [Fig. 1(b)], which is believed to be the source of exceptional electronic properties. 33 These junctions are
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Titania-sliver Composite Thin Film Coating On Glass For Photocatalsis And Potential Antimicrobial Application

Titania-sliver Composite Thin Film Coating On Glass For Photocatalsis And Potential Antimicrobial Application

5 Table 2.1: Aluminum Alloy Series and Description Source:www.matsci.ucdavis.edu/matsilt/HT_aluminum Major alloying element General properties General Uses none Excellent corrosion resis[r]

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Effects of Ion Doping on the Optical Properties of Dye Sensitized Solar Cells

Effects of Ion Doping on the Optical Properties of Dye Sensitized Solar Cells

The Zn 2+ optimum doping amount is 0.05%, because then the transfer rate of carriers of the fastest, the sepa- ration of electron hole pair efficiency is the highest, the photocatalytic activity is the strongest. When Zn 2+ dop- ing amount is less than 0.05%, the defect levels and impurity levels is separating center of electron-hole pairs; When Zn 2+ doping greater than 0.5%, the defect levels and impurity levels is recombination center of elec- tron-hole pairs. carrier recombination rate accelerated, electron-hole pairs separation efficiency decreases. 3.4. UV-Vis Spectra of Different Concentration Ion Doped TiO 2 Thin Film
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NEW PATENTS: April 198396-100

NEW PATENTS: April 198396-100

In a Pt thin film resistance element for use in a temperature sensor or gas sensor, a thin metal film is formed on an insulating substrate, a kerf is formed in the film t[r]

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Giesbrecht, Nadja
  

(2018):


	Methylammonium lead halide thin film crystallization for optoelectronic applications.


Dissertation, LMU München: Fakultät für Chemie und Pharmazie

Giesbrecht, Nadja (2018): Methylammonium lead halide thin film crystallization for optoelectronic applications. Dissertation, LMU München: Fakultät für Chemie und Pharmazie

Our results show that a significant improvement of at least 35 % in mobility occurs with a higher degree of crystal alignment in the perovskite films if the grain size is similar for both crystal facet alignments, indicating the benefits of purely aligned polycrystalline films, see Figure 5 – 4d. In our measurements, we see no clear trend according to anisotropy in charge transport of differently aligned perovskite films. Here, the films were measured laterally, while the high alignment of our samples is in the out-of-plane direction rather than in-plane. On the other hand, ToF measurements in the vertical direction of the film (thickness around 450 nm) do not provide any meaningful information as charge transport in this direction occurs on a faster timescale than the temporal resolution of our ToF setup, which is approximately two ns. 30
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Characterization Study of Conducting Polymer PANI-GO Nano Composite Thin Film Supercapacitor

Characterization Study of Conducting Polymer PANI-GO Nano Composite Thin Film Supercapacitor

FTIR spectral analysis of GO, synthesised PANI powder and PANI-GO Thin film as shown in figure 3.1 the spectral line (a) is indicating the fine GO nano powder, (b) indicating the line of synthesised PANI powder and (c) indicating as a spectral line of nano composite PANI-GO thin film. In line a) for graphene oxide are attributed to OH, C=O in COOH and C- O in COH/COC functional groups at presenting in the line of 3390, 1629 and 1495-1057 cm -1, 19 . The spectrum of PANI shown in figure 1 (b) transmittance beaks centring at 813, 1122,
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Thin film electroluminescence

Thin film electroluminescence

With the dielectric layer across each would given charge value, the therefore be the total device threshold voltage would be around 1 a 200 nm voltage dielectric layer drop for this devi[r]

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