Modification of Nanofiber Support Layer for Thin Film Composite Forward Osmosis Membranes via Layer-By-Layer Polyelectrolyte Deposition

Electrospun nanofiber-supported thin film composite membranes are among the most promising membranes for seawater desalination via forward osmosis. In this study, a high-performance electrospun polyvinylidenefluoride (PVDF) nanofiber-supported TFC membrane was successfully fabricated after molecular layer-by-layer polyelectrolyte deposition. Negatively-charged electrospun polyacrylic acid (PAA) nanofibers were deposited on electrospun PVDF nanofibers to form a support layer consisted of PVDF and PAA nanofibers. This resulted to a more hydrophilic support compared to the plain PVDF nanofiber support. The PVDF-PAA nanofiber support then underwent a layer-by-layer deposition of polyethylenimine (PEI) and PAA to form a polyelectrolyte layer on the nanofiber surface prior to interfacial polymerization, which forms the selective polyamide layer of TFC membranes. The resultant PVDF-LbL TFC membrane exhibited enhanced hydrophilicity and porosity, without sacrificing mechanical strength. As a result, it showed high pure water permeability and low structural parameter values of 4.12 Lm−2h−1bar−1 and 221 µm, respectively, significantly better compared to commercial FO membrane. Layer-by-layer deposition of polyelectrolyte is therefore a useful and practical modification method for fabrication of high performance nanofiber-supported TFC membrane.

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Modification of Nanofiber Support Layer for Thin Film Composite forward Osmosis Membranes via Layer-by-Layer Polyelectrolyte Deposition

Membranes ◽

10.3390/membranes8030070 ◽

2018 ◽

Vol 8 (3) ◽

pp. 70 ◽

Cited By ~ 18

Author(s):

Ralph Gonzales ◽

Myoung Park ◽

Leonard Tijing ◽

Dong Han ◽

Sherub Phuntsho ◽

...

Keyword(s):

Thin Film ◽

High Performance ◽

Forward Osmosis ◽

Composite Membranes ◽

Structural Parameter ◽

Layer By Layer ◽

Film Composite ◽

Thin Film Composite ◽

Layer Deposition ◽

Tfc Membrane

Electrospun nanofiber-supported thin film composite membranes are among the most promising membranes for seawater desalination via forward osmosis. In this study, a high-performance electrospun polyvinylidenefluoride (PVDF) nanofiber-supported thin film composite (TFC) membrane was successfully fabricated after molecular layer-by-layer polyelectrolyte deposition. Negatively-charged electrospun polyacrylic acid (PAA) nanofibers were deposited on electrospun PVDF nanofibers to form a support layer consisted of PVDF and PAA nanofibers. This resulted to a more hydrophilic support compared to the plain PVDF nanofiber support. The PVDF-PAA nanofiber support then underwent a layer-by-layer deposition of polyethylenimine (PEI) and PAA to form a polyelectrolyte layer on the nanofiber surface prior to interfacial polymerization, which forms the selective polyamide layer of TFC membranes. The resultant PVDF-LbL TFC membrane exhibited enhanced hydrophilicity and porosity, without sacrificing mechanical strength. As a result, it showed high pure water permeability and low structural parameter values of 4.12 L m−2 h−1 bar−1 and 221 µm, respectively, significantly better compared to commercial FO membrane. Layer-by-layer deposition of polyelectrolyte is therefore a useful and practical modification method for fabrication of high performance nanofiber-supported TFC membrane.

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Novel thin film composite membranes supported by cellulose triacetate porous substrates for high-performance forward osmosis

Polymer ◽

10.1016/j.polymer.2018.08.017 ◽

2018 ◽

Vol 153 ◽

pp. 150-160 ◽

Cited By ~ 10

Author(s):

Qing-Yun Wu ◽

Xiao-Yan Xing ◽

Yuan Yu ◽

Lin Gu ◽

Zhi-Kang Xu

Keyword(s):

Thin Film ◽

High Performance ◽

Forward Osmosis ◽

Composite Membranes ◽

Cellulose Triacetate ◽

Film Composite ◽

Thin Film Composite ◽

Porous Substrates

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Preparation of thin-film composite membranes supported with electrospun nanofibers for desalination by forward osmosis

Drinking Water Engineering and Science ◽

10.5194/dwes-13-51-2020 ◽

2020 ◽

Vol 13 (2) ◽

pp. 51-57

Author(s):

Mustafa Al-Furaiji ◽

Mohammed Kadhom ◽

Khairi Kalash ◽

Basma Waisi ◽

Noor Albayati

Keyword(s):

Thin Film ◽

Water Flux ◽

Applied Pressure ◽

Forward Osmosis ◽

Composite Membranes ◽

Polymerization Reaction ◽

Film Composite ◽

Salt Rejection ◽

Thin Film Composite ◽

Tfc Membrane

Abstract. The forward osmosis (FO) process has been considered to be a viable option for water desalination in comparison to the traditional processes like reverse osmosis, regarding energy consumption and economical operation. In this work, a polyacrylonitrile (PAN) nanofiber support layer was prepared using the electrospinning process as a modern method. Then, an interfacial polymerization reaction between m-phenylenediamine (MPD) and trimesoyl chloride (TMC) was carried out to generate a polyamide selective thin-film composite (TFC) membrane on the support layer. The TFC membrane was tested in FO mode (feed solution facing the active layer) using the standard methodology and compared to a commercially available cellulose triacetate membrane (CTA). The synthesized membrane showed a high performance in terms of water flux (16 Lm −2 h−1) but traded the salt rejection (4 gm−2 h−1) compared with the commercial CTA membrane (water flux = 13 Lm−2 h−1 and salt rejection = 3 gm−2 h−1) at no applied pressure and room temperature. Scanning electron microscopy (SEM), contact angle, mechanical properties, porosity, and performance characterizations were conducted to examine the membrane.

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Low-Cost High Performance Polyamide Thin Film Composite (Cellulose Triacetate/Graphene Oxide) Membranes for Forward Osmosis Desalination from Palm Fronds

Membranes ◽

10.3390/membranes12010006 ◽

2021 ◽

Vol 12 (1) ◽

pp. 6

Author(s):

Tarek S. Jamil ◽

Rabab A. Nasr ◽

Hussien A. Abbas ◽

Tamer I. M. Ragab ◽

Sinethemba Xabela ◽

...

Keyword(s):

Thin Film ◽

High Performance ◽

Low Cost ◽

Forward Osmosis ◽

Cellulose Triacetate ◽

Salt Flux ◽

Film Composite ◽

Thin Film Composite ◽

Tfc Membrane ◽

Palm Fronds

Novel low-cost cellulose triacetate-based membranes extracted from palm fronds have been fabricated through the phase–inversion procedure. The cellulose tri-acetate (CTA) membrane was modified by incorporation of graphene oxide (GO) prepared from palm fronds according to the modified Hummer method as well as the preparation of polyamide thin film composite CTA membranes to improve forward osmosis performance for seawater desalination. The surface characteristics and morphology of the prepared CTA, GO, and the fabricated membranes were investigated. The modified TFC prepared membrane had superior mechanical characteristics as well as permeation of water. The performance of the prepared membranes was tested using synthetic 2 M Sodium chloride (NaCl) feed solution. The water flux (Jw) of the thin-film composite (TFC) (CTA/0.3% GO) was 35 L/m2h, which is much higher than those of pure CTA and CTA/0.3% GO. Meanwhile, the salt reverse flux TFC (CTA/0.3% GO) was 1.1 g/m2h), which is much lower than those of pure CTA and CTA/0.3%. GO (Specific salt flux of TFC (CTA/0.3% GO) substrate membrane was 0.03 g/L indicating good water permeation and low reverse salt flux of the TFC membrane compared to CTA. A real saline water sample collected from Hurgada, Egypt, with totally dissolved solids of 42,643 mg/L with NaCl as the draw solution (DS) at 25 °C and flow rate 1.55 L/min, was used to demonstrate the high performance of the prepared TFC membrane. The chemical analysis of desalted permeated water sample revealed the high performance of the prepared TFC membrane. Consequently, the prepared low-cost forward osmosis (FO) thin-film composite CTA membranes can be introduced in the desalination industry to overcome the high cost of reverse osmosis membrane usage in water desalination.

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