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Multidisciplinary, innovative and high values development of high performance, cost-effective and environmentally acceptable separation systems is highly desired to tackle the sustainability challenges that facing current desalination technology. Owing to their versatility and immense potentials to evolve scientific and technical innovations, nanotechnology is probably one of the most prominent strategies that has gained growing scientific and public recognition to provide solutions that can extend the limits of sustainability in membrane desalination technology. This short review provides a brief insight into the roles and prospective of nanotechnology, particularly the nano-enabled membrane technology, to serve as a key element to render feasible solutions for sustainable development in membrane desalination technology. The contribution also highlights the strategies of transforming risk and challenges of this cutting edge technology into competitive advantage in order to timely and efficiently drive values in enhancing the desalination performance, profits and sustainability. The applications of nanomaterials and nanocomposite in membrane desalination are anticipated to foster untapped initiatives and innovation in fundamental science, engineering and technology to spearhead the new wave of leading edge sustainable membrane desalination technology. [ABSTRACT FROM AUTHOR]

This study focuses on the design and performance of a hybrid system consisting of a photocatalytic reactor and a membrane permeation cell. Initially, an ultraviolet lamp was installed in the photocatalytic reactor to decompose the organic pollutants in the presence of 200 ppm titanium-dioxide (TiO 2 ). Individual hydrocarbon pollutants were identified by gas chromatography–mass spectrometry (GC–MS) analysis of wastewater samples. Polyvinylidene fluoride (PVDF)/multi-walled carbon nanotube (MWCNT) nanocomposite membranes were fabricated to enhance the rejection, flux and fouling resistance for full filtration of pollutants from photocatalytic reactor such as decomposed refinery wastewater and TiO 2 photocatalyst. The nanocomposite membranes were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The TiO 2 cross-over during permeation was detected by using an atomic adsorption spectrometer, which proved that TiO 2 rejection was more than 99% for oxidized MWCNT nanocomposite membranes. Furthermore, GC–MS analysis was concluded over 90% decomposition which occurred by photocatalytic reaction and practically all pollutants were removed by ultrafiltration permeation cell. The nanocomposite membrane with 1.0 wt.% of oxidized MWCNTs incorporated in PVDF matrix was found to be the best nanocomposite membrane among all of the fabricated membranes for the filtration purposes, due to the over 99% rejection and excellent anti-fouling property. [ABSTRACT FROM AUTHOR]

Abstract: Sulfonated poly (ether ether ketone) (SPEEK) membrane with degree of sulfonation (DS) of 63% was modified by adding various amounts of Cloisite15A® clay. The effect of clay loading on the physical properties of SPEEK nanocomposite membranes was investigated. SPEEK mixed with 2.5wt.% of Cloisite15A® (SP63/2.5Cl) has been identified as the best composite formulation in this study. Subsequently, various amounts of 2,4,6-triaminopyrimidine (TAP) were further incorporated into SP63/2.5Cl formulation. The effect of TAP incorporation on the physical and performance properties of the membranes was studied. Nanometer scale distribution of Cloisite15A® in the SPEEK polymer matrix has been achieved by the assistance of TAP, as observed by the field emission scanning electron microscopy (FESEM). A complete exfoliated nanocomposite structure of SP63/2.5Cl/5.0TAP was confirmed by X-ray diffraction (XRD). The increase of Cloisite15A® content in the SPEEK membrane has dramatically improved the swelling behavior and barrier properties towards methanol. The SP63/2.5Cl/5.0TAP polymer–clay nanocomposite membrane served as a promising alternative proton exchange membrane (PEM) for DMFC applications with superior DMFC performance compared to commercial Nafion®112. [Copyright &y& Elsevier]

Abstract: Effect of radiation dose and carbon nanotubes (CNT) on the mechanical properties of standard Malaysian rubber (SMR) was investigated in this study. SMR nanocomposites containing 1–7phr CNT were prepared using the solvent casting method and the nanocomposites were radiated at doses of 50–200kGy. The change in mechanical properties, especially, tensile strength (Ts), elongation at break (Eb), hardness and tensile modulus at 100% elongation (M 100) were studied as a function of radiation dose. The structure and morphology of reinforced natural rubber was investigated by FESEM, TEM and AFM in order to gain further evidence on the radiation-induced crosslinking. It was found that the Ts, M 100 and the hardness of the SMR/CNT nanocomposites significantly increased with radiation dose; the elongation at break exhibited an increase up to 100kGy, and a downward trend thereafter. Results on gel fraction further confirmed the crosslinking of SMR/CNT nanocomposites upon radiation. [ABSTRACT FROM AUTHOR]

Abstract: Sulfonated poly (ether ether ketone) (SPEEK)/Cloisite 15A® nanocomposite membranes were fabricated by incorporating 2,4,6-triaminopyrimidine (TAP) as compatiblizer and characterized for DMFC application. The SPEEK-nanocomposite membranes were prepared via solution intercalation method. The membranes were then characterized based on their thermal and physical properties as a function of Cloisite 15A® and TAP loading. The characteristics of the SPEEK nanocomposite membranes were then compared with the parent SPEEK membrane and the commercially available Nafion 112 membrane. The XRD confirmed that intercalation took place in the SPEEK nanocomposite membranes. The membrane stability, i.e. the liquid uptake in water and in the aqueous methanol solution, as well as the mechanical and thermal stability significantly were improved with the Cloisite 15A® and TAP loadings into the SPEEK polymer matrix. The barrier performance of SPEEK/Cloisite 15A®/TAP was significantly enhanced to compete with the expensive Nafion 112 membrane. Higher proton conductivity of 3.87×10−3 Scm−1, which is higher than that of the parent SPEEK membrane, was also attained. [Copyright &y& Elsevier]

This study involves the preparation of a double-skinned thin film composite (TFC) and thin film nanocomposite (TFN) hollow fiber (HF) membrane for forward osmosis (FO) applications. The porous substrate consisted of a Polyvinyl chloride (PVC) / Polycarbonate (PC) blend HF membrane. Interfacial polymerization (IP) was then applied to coat a polyamide (PA) layer on the lumen surface and the porous substrate's outer surface. In addition, the impact of the outer PA active layer and the addition of nanoparticles to the outer selective layer on the FO flux and internal concentration polarization (ICP) were studied. By adding the second active layer to the substrate, water flux, reverse salt flux and ICP decreased. Also, the decline of water flux decreased over time due to the fouling agent. To compensate for the decrease in water flux in the double-skinned membrane, graphene oxide (GO) nanoparticles with 0.05% and 0.1%wt were added to the outer active layer. Addition of 0.1%wt graphene oxide nanoparticle to the outer active layer can help to improve water flux about 78% without spoiling the reverse salt flux. Moreover, the performance of double-skinned membranes against osmotic dilution process for oily wastewater treatment was investigated. The findings of this study demonstrated that the novel double-skinned TFN HF membrane exhibited high FO performance with low ICP and fouling. [Display omitted] • Inclusion of a second active layer without reducing the reverse salt flux and fouling. • To improve fouling resistance of membrane, GO was added to second active layer. • By adding GO to outer active layer, reverse salt flux and fouling was reduced. • The Hermia model showed intermediate blocking in neat membrane. • The predominant fouling in double-skin membranes is cake formation. [ABSTRACT FROM AUTHOR]

Polyvinylidene Fluoride (PVDF) nanocomposite membrane consisting of electrospun titanium dioxide (TiO 2 ) nanofibers (PVDF/e-TiO 2 ) was prepared by hot pressing the as-spun TiO 2 nanofibers onto PVDF flat sheet membrane. The TiO 2 nanofibers act as a photocatalyst to decompose organic pollutants present in wastewater under UV irradiation, while PVDF membrane acts as a support. The hot press technique was carried out by applying the operating temperatures at 100 °C, 160 °C and 180 °C for 30 min. The nanocomposite membrane was characterized by FESEM, EDX, contact angle measurement, DSC, and UV–Vis–NIR spectroscopy. The FESEM images and EDX analysis showed good adhesion and dispersion of TiO 2 nanofibers in PVDF membrane. The hot-pressed PVDF/e-TiO 2 membrane at lower temperature (100 °C) (PVDF/e-TiO 2 -100) is more hydrophilic, higher pure water flux and has higher UV absorbance compared to the PVDF/e-TiO 2 -160 and PVDF/e-TiO 2 -180 membranes. The concentration of bisphenol A (BPA) in the feed solution was found to reduce with the degradation percentage of 63% to 85% after the PVDF/e-TiO 2 nanocomposite membrane was treated with UV radiation. The results indicated that the introduction of TiO 2 nanofibers in PVDF-based nanocomposite membrane via hot pressing indeed plays an important role towards enhancing the degradation and filtration of organic pollutants such as BPA. [ABSTRACT FROM AUTHOR]

This study investigated the potential of silver lactate (SL)-holloysite nanotube clay (HNTs) nano-filler embedded into the polyvinylidene fluoride (PVDF) polymer matrix as an antibacterial separator. Three different nanocomposite membranes were fabricated via phase inversion technique aimed to enhance the permeation flux and fouling resistance with complete bacterial rejection. HNT has been modified by N-β-(aminoethyl)-ɣ-aminopropyltrimethoxy silane (AEAPTMS) aiming for immobilization of SL on the surface HNT during dope preparation. Salmonella and Enterobacter aerogenes ( E. aerogenes ) were considered as two types of bacteria to be removed from contaminated water in this experimental work. Nanocomposite membranes were characterized and analyzed by thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM) combined with energy dispersive X-ray (EDX), X-ray photoelectron spectroscope (XPS), atomic force microscopy (AFM), contact angle, molecular weight cut-off (MWCO) and tensile strength. Potential silver ion loss was assessed by measuring the silver content in the coagulation bath and in the UF permeate using inductive-coupled plasma mass spectrometer (ICP-MS). Moreover, antibacterial effect of the membrane was examined in terms of removal of microorganisms by filtration, Log Reduction Value (LRV) and thickness of inhibition zone. From the experimental results, the prepared nanocomposite membranes have shown more than 99% bacterial rejection, LRV of more than 3 and broad inhibition zones in the agar plate. In particular, the nanocomposite membrane consisting M-HNTs/SL/PVDF showed significant improvement in permeation flux and flux declination among all the tested membranes. It was also found that modification of HNTs resulted in reduction of silver leaching by uniform distributing of SL, which contributed to significant inhibition for both types of growth bacteria within 24 h of incubation. [ABSTRACT FROM AUTHOR]

Recently, membrane technology has gained much momentum in the field of carbon capture and storage due to its practicality and energy efficiency. In this work, thin film nanocomposite (TFN) membranes embedded with polymethyl methacrylate (PMMA) grafted multi-walled carbon nanotubes (MWNTs) were successfully fabricated. The effects of nanofillers modification on the resultant membranes morphology and gas separation performance have been highlighted. TFN incorporated with milled PMMA grafted MWNTs showed 29% increment in CO 2 permeance at 70.5 GPU with 47% and 9% enhancement in CO 2 /N 2 and CO 2 /CH 4 selectivity, respectively compared to the thin film composite counterpart. While the improvement was mainly attributed to the presence of highly diffusive channels upon the addition of MWNTs, PMMA grafting also played an important role in ensuring well nanofillers dispersion and good compatibility with the polyamide thin film. Uncovering the construct of membrane fabrication could pave facile yet versatile way for the development of effective membranes for greenhouse gas removal. [ABSTRACT FROM AUTHOR]

Reverse osmosis (RO) based desalination is one of the most important and widely recognized technologies for production of fresh water from saline water. Since its conception and initiation, a significant development has been witnessed in this technology w.r.t. materials, synthesis techniques, modification and modules over the last few decades. The working of a RO plant inclusive of the pretreatment and post-treatment procedures has been briefly discussed in the article. The main objective of this review is to highlight the historical milestones achieved in RO technology in terms of membrane performance, the developments seen over the last few years and the challenges perceived. The material properties of the membrane dominate the performance of a RO process. The emergence of nano-technology and biomimetic RO membranes as the futuristic tools is capable of revolutionizing the entire RO process. Hence the development of nano-structured membranes involving thin film nano-composite membranes, carbon-nanotube membranes and aquaporin-based membranes has been focussed in detail. The problems associated with a RO process such as scaling, brine disposal and boron removal are briefed and the measures adopted to address the same have been discussed. [ABSTRACT FROM AUTHOR]

Eliminating phenol and other contaminants from wastewater is an essential step in addressing environmental issues. Using tailored photocatalysts is essential for the effective degradation of phenol via photocatalysis. The main objective of this study is to produce TiO 2 /ZnO/AgI nanocomposites employing the reflux approach in order to enhance the degradation of phenol in the presence of UV radiation. The nanocomposite incorporates TiO 2 and ZnO, resulting in a narrowed band gap that enhances photocatalytic activity. The addition of AgI enhances electron transport capacities, resulting in an inclusive augmentation in performance. The physicochemical properties of the nanocomposite were extensively investigated applying an array of advanced techniques including as XRD, BET, FESEM, TEM, EDX and TGA spectroscopy practices. The combined effect of TiO 2 , ZnO, and AgI exhibits an approximately 100 % degradation of phenol, exceeding the individual performance of each component. The outcomes indicated that the operational parameters have a substantial impact on the photocatalytic activity, and the addition of H 2 O 2 also improves degradation. The ideal conditions require a low concentration of H 2 O 2 and a dose of 0.3 g/350 mL of nanocomposite. The reaction rate constant was reported as 6.96 × 10−3 min−1 under optimised conditions. The ternary nanocomposite exhibited recyclability for four successive cycles, eventually displaying ∼88 % degradation. The TiO 2 /ZnO/AgI nanocomposite system exhibits significant photocatalytic efficiency, which has important consequences for addressing environmental concerns caused by the persistent existence of various organic contaminants in water sources. [Display omitted] • TiO 2 /ZnO/AgI ternary nanocomposites was synthesized for phenol photodegradation. • TiO 2 /ZnO/AgI ternary nanocomposites showed enhanced photocatalytic performance of 100 % phenol degradation. • TiO 2 /ZnO/AgI ternary nanocomposites demonstrated excellent recyclability of ∼88 % after four continue cycles. • Effect of pollutant concentration, H 2 O 2 on TiO 2 /ZnO/AgI ternary nanocomposites also considered under batch mode. [ABSTRACT FROM AUTHOR]

Abstract: Regenerated cellulose/montmorillonite (RC/MMT) nanocomposite films were successfully prepared in ionic liquid, 1-butyl-3-methylimidazolium chloride (BMIMCl) using solution casting method. The effect of MMT loading on the thermal, mechanical, gas permeability and water absorption properties of the nanocomposite films was investigated. X-ray diffraction analysis revealed a cellulose II crystalline structure and well dispersed MMT in RC/MMT nanocomposite films. Presence of MMT enhanced the thermal and thermal-oxidative stability and char yield of RC. The tensile strength and Young''s modulus of RC films improved by 12% and 40%, respectively with the addition of 6wt.% MMT. RC/MMT nanocomposite films exhibited improved gas barrier properties and water absorption resistance compared to RC. The results demonstrated that there is a possible interface interaction between cellulose and MMT which yielded better thermal and mechanical properties of the nanocomposite films as compared to pure cellulose. [Copyright &y& Elsevier]

Abstract: Carbon nanotube based nanocomposite membranes have been fabricated through solution casting by embedding multi-walled carbon nanotubes (MWCNTs) within polyetherimide (PEI) polymer host matrix. In order to achieve fine dispersion of nanotubes and facilitate strong interfacial adhesion with the polymer matrix, the nanotubes were first treated with surfactants of different charges, namely anionic sodium dodecyl chloride, cationic cetyl trimethyl ammonium chloride and non-ionic Triton X100, prior to the dispersion in the PEI dope solution. Dispersion of MWCNTs in N-methyl-2-pyrrolidone solvent showed that the agglomeration and entanglement of the nanotubes were greatly reduced upon the addition of Triton X100. Scanning electron microscopy and atomic force microscopy examination has evidenced the compatibility of Triton X100 dispersed MWCNTs with the polymer matrix in which a promising dispersion and adhesion has been observed at the MWCNT-PEI interface. The increase in both thermal stability and mechanical strength of the resulting Triton X100 dispersed MWCNT/PEI nanocomposite indicated the improved interaction between MWCNTs and PEI. This study demonstrated the role of Triton X100 in facilitating the synergetic effects of MWCNTs and PEI where the resulting composite membrane is anticipated to have potential application in membrane based gas separation. [ABSTRACT FROM AUTHOR]

• Review on new/modified IP techniques for defect-less TFN membrane fabrication. • Important characteristics of nanofillers to generate PA layer with high integrity. • Effects of nanomaterials on membrane physicochemical properties and performances. Thin film composite (TFC) reverse osmosis (RO) membrane has been dominating commercial desalination process for several decades since its inception in the 1970s. Despite the ability of generating high quality water at promising water permeability, the commercial TFC RO membrane is still susceptible to fouling and chlorine attack which lead to performance instability as a function of operation time. Over the past decade, the prowess of nanomaterials integration in overcoming the drawbacks of conventional TFC membrane has been proven by many research studies and this has led to the significant progress of thin film nanocomposite (TFN) membrane development. However, it remains a great challenge in integrating the inorganic nanomaterials with the polyamide (PA) selective layer of TFN membrane due to the incompatibility between organic and inorganic materials and the uneven distribution of nanomaterials. In view of this, this article intends to critically review various fabrication techniques that have been developed or modified to incorporate nanofillers within or atop PA layer for the development of TFN membranes. In addition, the essential characteristics of nanofillers in order to achieve good integration with PA layer as well as their impacts in improving membrane performance with respect to water flux, rejection, antifouling, antibacterial and chlorine stability are also reviewed. We hope this review article could provide insights to researchers in fabricating defect-free TFN RO membranes for enhanced water desalination. [ABSTRACT FROM AUTHOR]

In this work, tailor-made graphene oxide (GO) incorporated thin film nanocomposite (TFN) membranes based on novel interfacial polymerization (IP) technique were presented. The embedment of GO nanosheets within ultrathin cross-linked polyamide (PA) layer was successfully achieved without forming particle agglomeration that could affect structural integrity. A total of five composite membranes with different GO loadings (0, 0.01, 0.02, 0.03 and 0.04 g/m 2 ) were fabricated and these membranes were characterized using TEM, FESEM, XPS, ATR-FTIR and contact angle goniometer to evaluate the impact of GO loading on the physicochemical properties of PA selective layer. It is found that with the presence of GO, the TFN membranes exhibited higher surface hydrophilicity due to increment in hydroxyl and carboxyl groups in PA layer, hence, improved the attraction between water molecules and membrane surface. Upon incorporation of 0.02 g/m 2 of GO, the resultant TFN membrane achieved 95.8% and 97.7% removal rate for Na 2 SO 4 and MgSO 4 , respectively along with 31.4% higher water flux than the membrane contained no GO. More importantly, this work demonstrated the broad applicability of novel IP technique in synthesizing TFN membranes with improved antifouling properties independent of the PA chemistry. [ABSTRACT FROM AUTHOR]

Thin film composite (TFC) reverse osmosis (RO) membrane, which has been widely applied for desalination, consists of an ultra-thin polyamide (PA) coating layer that supported on a porous support membrane. The main interest of this work is to perform facile acid modification on the polysulfone (PS) support of TFC and thin film nanocomposite (TFN) membranes. The PS support was acid treated with sulfuric acid (H 2 SO 4 ) at a concentration ranging from 1 to 2 M for 24–72 h. Response surface methodology (RSM) based on historical data design (HDD) was used to verify the optimum condition of support membrane with respect to NaCl rejection and water permeability. The highest water permeability was achieved at 1.13 L/m 2 .h.bar when nanoparticles loading of 0.03% was incorporated into the PA layer and PS support treated at 1.5 M H 2 SO 4 for 48 h. The NaCl rejection of all the synthesized membranes was found to be above 96%. [ABSTRACT FROM AUTHOR]

This study explores the potential of novel hybrid polyvinylidene fluoride/titanate nanotube (PVDF-TNT) photocatalytic membranes for the colour removal of aerobically treated palm oil mill effluent (AT-POME) in a submerged membrane photo reactor (SMPR). Different loadings (0–1.0 wt%) of TNT photocatalysts were physically mixed into PVDF dope solution prior to the membrane fabrication through dry/wet phase inversion process. The membranes modules were subsequently fitted into a 15 L SMPR tank, with a UV light source placed at the center of the SMPR. The performance analysis indicated that PVDF-TNT0.5 showed the best colour removal of 67.3%. The synergistic effects rendered by both membrane filtration and photocatalysis have remarkably improved the colour removal efficiency compared to filtration alone that barely exhibited colour removal of 34.2%. The operating conditions of the SMPR, such as initial concentration and pH of the feed AT-POME were also investigated. The photocatalytic activity has greatly reduced the fouling susceptibility of PVDF-TNT membranes, where flux loss of only 5.7% was observed after 5 cycles of usage. With its promising performance in terms of colour removal, flux and low membrane fouling susceptibility, this hybrid SMPR holds great potential to be directly applied in the current POME treatment system to improve the effluent quality and reduce freshwater consumption for palm oil extraction process. [ABSTRACT FROM AUTHOR]

The stability of SPEEK/Cloisite ® /triaminopyrimidine (SP/CL/TAP) nanocomposite membrane against radical attack during DMFC operation was elucidated by the Fenton reagent test. The nanocomposite membrane was soaked in the Fenton reagent solution with 0.8–50 ppm iron salts concentration for up to 96 h. The results indicate that presence of Cloisite ® inorganic particles can improve the stability of SP/CL/TAP nanocomposite membrane against the radical attack. FT-IR characterization combined with DFT study has shown that C‒O‒C and ‒SO 3 H bonding with phenylene ring, and hydrogen bonding between SPEEK, Cloisite ® , and TAP are vulnerable to the radical attack. Loss of these functional groups has caused structural deformation, deterioration of mechanical strength, and changes of hydrophilicity in the SP/CL/TAP nanocomposite membrane. Additionally, changes in its chemical structure have caused its water uptake, proton conductivity, and methanol barrier properties to drop, up to 2 × higher than the Nafion ® 117 membrane. However, the selectivity value of the SP/CL/TAP nanocomposite membrane (27,037 S∙s/cm 3 ) remains higher than the Nafion ® 117 membrane (3292 S∙s/cm 3 ) due to its lower methanol permeability value (2.72 × 10 −7 cm 2 /s) as compared to Nafion ® 117 membrane (2.95 × 10 −6 cm 2 /s). Based on the correlation graph, the SP/CL/TAP nanocomposite membrane could operate as PEM in the DMFC system up to 9800 h. Based on the results, it can be concluded that the SP/CL/TAP nanocomposite membrane has good stability in DMFC harsh environment and suitable to be employed as PEM for high-performance and long lifespan DMFC system. [ABSTRACT FROM AUTHOR]

• Thermal stable SPEEK membrane was fabricated with halloysite nanoclay and functionalized GO nanocomposites. • The silane and sulfonic acid group in the nanocomposite SPEEK membrane increased IEC and low methanol permeability. • The nanoclay and fGO membranes have shown significant proton conductivity and power density than pristine SPEEK membrane. Membrane-based fuel cells, particularly methanol-based fuel cells, are thriving areas with high efficiency, less material consumption, and low emission of pollutants. But commercial membranes have less thermal withstanding ability and high cost, so alternative polymeric membranes have been developed with desired properties to overcome this issue. The SPEEK membrane was fabricated with halloysite nanoclay and functionalized graphene oxide (f-GO) nanocomposites at various concentrations via dry phase inversion. The sulfonic acid group in the SPEEK and silane functionalization of GO enhanced the Ion exchange capacity from 0.22 to 0.35 meq/g which enhances the proton conductivity. Furthermore, the thermal stability and hydrophilicity of the pristine SPEEK membrane were reformed with addition of halloysite nanoclay and f-GO in SPEEK membrane. The presence of nanocomposite on the surface of the SPEEK membranes was confirmed via scanning electron microscope (SEM) analysis. The 3 wt% halloysite nanoclay and 2 wt% of f-GO composite membrane was hold the 0.47 mS cm−1 of proton conductivity and 72.2 mW cm−2 of power density, whereas pristine SPEEK membrane was 0.31 mS cm−1 and 28 mW cm−2, respectively. The 3 wt% halloysite incorporated SPEEK membrane and 1.5 wt% f-GO incorporated SPEEK membrane was shown better proton conductivity, which act as a prominent membrane for direct methanol fuel cell (DMFC) applications. [ABSTRACT FROM AUTHOR]

One of the most critical issues encountered by thin film composite (TFC) nanofiltration (NF) membrane in water softening is the trade-off between water flux and salt rejection. A novel thin film nanocomposite (TFN) membrane was fabricated by incorporating graphene oxide (GO) of different quantity (ranging from zero to 0.5 wt.%) into polysulfone (PSf) microporous substrate. Polyamide layer was formed on top of the neat PSf and PSf-GO substrate to produce TFC and TFN membrane, respectively through the interfacial polymerization of piperazine and trimesoyl chloride monomers. With respect to pure water flux, TFN membrane made of 0.3 wt.% GO exhibited the highest water permeability with rejections for Na 2 SO 4 , MgSO 4 , MgCl 2 and NaCl recorded at 95.2%, 91.1%, 62.1% and 59.5%, respectively. As compared to TFC control membrane, GO incorporated TFN membranes exhibited higher pure water flux, salt solution permeability and salt rejection. This proved that GO plays an important role in increasing both membrane hydrophilicity and surface negativity. Most importantly, TFN membrane made of nanocomposite substrate served as a promising solution to overcome the trade-off effect between water flux and salt rejection of TFC membrane owing to the improved properties of substrate upon incorporation of highly hydrophilic and negatively charged GO nanosheets. [ABSTRACT FROM AUTHOR]

In this work, an environmental friendly RC/N-TiO 2 nanocomposite thin film was designed as a green portable photocatalyst by utilizing recycled newspaper as sustainable cellulose resource. Investigations on the influence of N-doped TiO 2 nanorods incorporation on the structural and morphological properties of RC/N-TiO 2 nanocomposite thin film are presented. The resulting nanocomposite thin film was characterized by FESEM, AFM, FTIR, UV–vis–NIR spectroscopy, and XPS analysis. The results suggested that there was a remarkable compatibility between cellulose and N-doped TiO 2 nanorods anchored onto the surface of the RC/N-TiO 2 nanocomposite thin film. Under UV and visible irradiation, the RC/N-TiO 2 nanocomposite thin film showed remarkable photocatalytic activity for the degradation of methylene blue solution with degradation percentage of 96% and 78.8%, respectively. It is crucial to note that the resulting portable photocatalyst produced via an environmental and green technique in its fabrication process has good potential in the field of water and wastewater treatment application. [ABSTRACT FROM AUTHOR]

This review focuses on the development of polyamide (PA) thin film nanocomposite (TFN) membranes for various aqueous media-based separation processes such as nanofiltration, reverse osmosis and forward osmosis since the concept of TFN was introduced in year 2007. Although the total number of published TFN articles falls far short of the articles of the well-known thin film composite (TFC) membranes, its growth rate is significant, particularly since 2012. Generally, by incorporating an appropriate amount of nanofiller into a thin selective PA layer of a composite membrane, one could produce TFN membranes with enhanced separation characteristics as compared to the conventional TFC membrane. For certain cases, the resulting TFN membranes demonstrate not only excellent antifouling resistance and/or greater antibacterial effect, but also possibly overcome the trade-off effect between water permeability and solute selectivity. Furthermore, this review attempts to give the readers insights into the difficulties of incorporating inorganic nanomaterials into the organic PA layer whose thickness usually falls in a range of several-hundred nanometers. It is also intended to show new possible approaches to overcome these challenges in TFN membrane fabrication. [ABSTRACT FROM AUTHOR]

In this work, flat sheet polysulfone (PSf)-based membranes modified with inorganic hydrous aluminum oxide (HAO) nanoparticles were used as antifouling ultrafiltration membranes for removing oil molecules from oily solution. SEM, AFM and FTIR analyses were performed on the fabricated membranes to study the effect of HAO nanoparticles loading on the membrane properties. The membrane hydrophilicity and separation performance were determined through contact angle measurement and cross-flow ultrafiltration of oily solution, respectively. Results showed that the hydrophilicity of HAO-modified membrane was increased remarkably upon addition of the highest weight ratio of HAO nanoparticles to PSf (i.e. 2:1), which led to a significant rise in permeate flux, achieving 1194 L/m 2 h bar in comparison to 151 L/m 2 h bar shown by the plain PSf membrane. With respect to oil removal efficiency, the modified membrane was found to exhibit almost complete elimination of oil molecules with flux recovery ratio of around 67% after a simple water washing process. The promising results achieved by the modified PSf membrane could be mainly due to the presence of hydroxyl functional groups on the membrane surface upon addition of highly hydrophilic HAO nanoparticles, which improved not only membrane water permeability but also its antifouling ability. [ABSTRACT FROM AUTHOR]

In this work, titanate nanotubes (TNTs) were self-synthesized and amino functionalized to produce titanate nanotubes (NH 2 -TNTs) for thin film nanocomposite (TFN) reverse osmosis (RO) membrane fabrication. The novel RO membranes were fabricated by embedding NH 2 -TNTs of different quantities into polyamide (PA) layer. The nanotubular morphology of NH 2 -TNTs was studied using TEM while FTIR was employed to confirm the reaction of TNTs with [1-(2-amino-ethyl)-3-aminopropyl] trimethoxysilane. The effect of NH 2 -TNTs on the PA layer of TFN with respect to surface morphology, separation performance and antifouling properties was thoroughly investigated and discussed. The presence of NH 2 -TNTs in PA layer was verified using XPS while the “leaf-like” outgrowth morphology of PA layer was observed using FESEM. Results showed that the TFN membrane with 0.05% NH 2 -TNTs embedded was the most promising membrane as it exhibited 93% higher water flux than the control thin film composite (TFC) membrane, without compensating NaCl rejection. In terms of organic fouling tendency, the TFN0.05 membrane also showed higher tolerance compared to the control membrane during RO process. Furthermore, as high as 94% of the water flux of TFN0.05 was able to retrieve by a simple water rinse process, which suggests that organic fouling in TFN0.05 is highly reversible. [ABSTRACT FROM AUTHOR]

In the present study, PANI (polyaniline)-nanofibers were synthesized by interfacial polymerization technique, dispersed in n-Methyl-2-Pyrrolidone (NMP) solvent and blended with PVP (Polyvinylpyrrolidone)/PSf (Polysulfone) for preparing the novel hollow fiber membrane by dry–wet spinning technique. The newly prepared nanocomposite ultrafiltration hollow fiber membrane is characterized by Scanning Electron Microscope (SEM), Contact Angle, Zeta Potential and Differential Scanning Calorimeter (DSC). Filtration studies are conducted to measure the membrane pure water flux (PWF), rejection of hazardous dye (Reactive Red 120) and fouling resistance. The maximum rejections are obtained for M 0.5 membrane with 99.25% rejection of RR120 hazardous dye at 2 bar pressure. The pure water flux, percentage rejection, antifouling property and thermal resistance increased with an increase in PANI-nanofiber concentration. The contact angle of the membrane decreased with increasing PANI-nanofiber concentration, which indicated increased hydrophilicity of the new membranes. [ABSTRACT FROM AUTHOR]

Abstract: Hydrous manganese dioxide (HMO) nanoparticles were synthesized and incorporated in polyethersulfone (PES) to fabricate nanocomposite mixed matrix membranes (MMMs) for ultrafiltration (UF). The resulting membranes were characterized by XRD, FTIR, contact angle goniometer, SEM and AFM before further subjected to water permeation test and UF of bovine serum albumin (BSA) solution. It was found that contact angle of membrane decreased remarkably while porosity increased with an increase in HMO nanoparticle loading. The pore size at the skin layer however decreased as observed both by SEM and AFM. As for the UF experiments, pure water permeation rate increased remarkably with increasing nanoparticle loading but the permeation rate of BSA did not increase very much. Interestingly, the membrane flux recovery by washing with DI water was considerably enhanced by an increase in nanoparticle loading, indicating the improvement in membrane anti-fouling property upon HMO nanoparticle addition. The observed phenomena can be explained by the increase in membrane hydrophilicity and the formation of patterned surface with an increase in nanoparticle loading. [Copyright &y& Elsevier]

Highlights: [•] Modifications on PSf substrate of TFC membrane using TiO2 nanoparticles. [•] Performances of PSf substrate were improved upon addition of TiO2 nanoparticles. [•] TFN FO membrane with small S value and minimum ICP was able to produce. [ABSTRACT FROM AUTHOR]

Abstract: Realizing that one of the most important challenges in the forward osmosis (FO) membrane is internal concentration polarization (ICP), thin film nanocomposite (TFN) membranes were prepared by incorporating different loadings of titanium dioxide (TiO2) nanoparticles (ranging from 0 to 0.90wt%) into the polysulfone (PSf) substrate in order to reduce ICP. The nanocomposite substrates prepared were characterized with respect to hydrophilicity, overall porosity, surface roughness and cross-sectional morphology by different methods. Results revealed that both hydrophilicity and porosity of the substrate were increased upon addition of TiO2 nanoparticles. Moreover, a large number of finger-like macrovoids were developed by increasing the loading of TiO2 nanoparticles, leading to enhancement in water permeability. As for the FO performance tested at AL-FS orientation and with DI water as feed and 0.5M NaCl as draw solution, the TFN membrane prepared using PSf substrate embedded with 0.60wt% TiO2 nanoparticles (designated as TFN0.60) exhibited the most promising result by showing water flux of 18.81L/m2 h, i.e. 97% higher than the control TFC membrane prepared by substrate without TiO2 incorporation (designated as TFC), with no significant change in reverse solute flux. Compared to the control TFC membrane, the FO water flux of TFN0.60 was also reported to increase significantly from 4.2 to 8.1L/m2 h (AL-FS orientation) and from 6.9 to 13.8L/m2 h (AL-DS orientation) when seawater was used as feed solution and 2M NaCl was used as draw solution. The increase in water flux can be attributed to the decrease in structural parameter (S value=0.39mm), mainly due to the formation of finger-liked macrovoids that connect the top and bottom layer of the substrate and reduce the tortuosity, resulting in decreased ICP. Although further increasing TiO2 nanoparticles loading to 0.90wt% could increase membrane water permeability, the FO performance was compromised by a significant increase in reverse solute flux. To the best knowledge of the authors, this is the first report on TFN membrane using PSf-TiO2 nanocomposite substrate for FO applications. [Copyright &y& Elsevier]

Recently, forward osmosis (FO) has attracted a great deal of attention in desalination and wastewater treatment. Nevertheless, there are several critical challenges such as the need for new advances in designing membranes that must be met to enhance the water flux in FO processes, control the reverse salt flux, concentration polarization and fouling. Therefore, designing a suitable membrane with a high-water flux, low reverse salt flux, low fouling, and controlled concentration polarization seems to be essential. Thin film composite (TFC) membranes are the most widely used membranes in the FO field. Extensive research has been performed to fabricate and design high performance TFC membranes which can be exclusively used in FO processes. This paper aims to review three types of TFC membranes i.e. TFC's with polyamide active layer (TFC-A), thin film nanocomposites (TFC-N) and double-skinned TFC membranes (TFC-D) in flat sheet and hollow fiber configuration. Finally, an attempt is made to generate a general performance curve based on the water flux and reverse salt flux of these three TFC FO types and the future direction of the R and D on the FO membrane are discussed. • A general performance curve for TFC-FO membranes was generated. • Active layer modified TFNs and double-skinned membranes possess very high potential for FO. • More researches should be performed on the less considered conditions of FO. [ABSTRACT FROM AUTHOR]