Neat Membrane Research Articles

High Selective Mixed Membranes Based on Mesoporous MCM-41 and MCM-41-NH2 Particles in a Polysulfone Matrix.

The development of membrane technology for gas separation processes evolved with the fabrication of so-called mixed matrix membranes (MMMs) as an alternative to neat polymers, in order to improve the overall membrane effectiveness. Once the mixed matrix membranes are used, the gas separation properties of the porous materials used as fillers are combined with the economical processability and desirable mechanical properties of polymer matrix. Mixed mesoporous silica/polymer membranes with high CO2 and O2 permeability and selectivity were designed and prepared by incorporating MCM-41 particles into a polymer matrix. Ordered mesoporous silica MCM-41 with high surface confirmed by BET analysis were obtained and functionalized with amino groups. In order to obtain the mixed membranes, the mesoporous silica was embedded into the polysulfone matrix (PSF). Flat mixed matrix membranes with 5, 10, and 20 wt% MCM-41 and MCM-41-NH2 loadings have been prepared via the polymer solution casting method. The phase's interactions were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR) and thermogravimetry (TGA), while the gas separation performances were evaluated using pure gases (CO2, O2, N2). The MCM-41/PSF and MCM-41-NH2/PSF membranes exhibited increased permeabilities for O2 (between 1.2 and 1.7 Barrer) and CO2 (between 4.2 and 8.1 Barrer) compared to the neat membrane (0.8 Barrer). The loss of selectivity for the O2/N2 (between 6 and 8%) and CO2/N2 (between 25 and 41%) gas pairs was not significant compared with the pure membrane (8 and 39%, respectively). The MCM-41/PSF membranes were more selective for CO2/N2 than the O2/N2 pair, due to the size difference between CO2 and N2 molecules and to the condensability of CO2, leading to an increase of solubility. Stronger interactions have been noticed for MCM-41-NH2/PSF membranes due to the amino groups, with the selectivity increasing for both gas pairs compared with the MCM-41/PSF membranes.

Mixed matrix PES-based nanofiltration membrane decorated by (Fe3O4–polyvinylpyrrolidone) composite nanoparticles with intensified antifouling and separation characteristics

In this study, the physico-chemical properties, separation performance and antifouling ability of mixed matrix PES-based nanofiltration membranes decorated by (Fe3O4–polyvinylpyrrolidone) composite nanoparticles were investigated. The morphology of resulted membranes was characterized by scanning electron microscopy)SEM), scanning optical microscopy (SOM) and 3D surface images. The effect of incorporated nanoparticles on membrane properties and performance was determined using water contact angle, water content, membrane pore size and porosity, tensile strength, water flux, salt rejection and BSA solution filtration. The membrane water content was enhanced slightly by embedding Fe3O4/PVP up to 0.1wt.% in membrane body and then reduced again by more NPs ratio. The water contact angle also decreased from 65.18° for neat membrane to 50.5° for the modified ones. All mixed matrix membranes showed higher water flux compared to pristine membrane that measured 3.14(L/m2h) for bare membrane and 9.96 (L/m2h) for the superior ones. Salt rejection measured 82% for the pristine membrane whereas that was between 77%–90% for the nanocomposite membranes. Membrane tensile strength also improved by increase of composite NPs ratio into the polymer matrix. The nanocomposite membranes showed more BSA solution flux and outstanding antifouling properties compared to bare ones. The FRR measured ∼46.2% for bare membrane whereas that was (∼69.9% to ∼89.5%) for the nanocomposite membranes.

Optimization of Epoxy Resin: An Investigation of Eggshell as a Synergic Filler.

Epoxy resin based on bisphenol A diglycidyl ether/anhydride methyl tetrahydrophthalic/2,4,6-tris(dimethylaminomethyl)phenol (DGEBA/MTHPA/DEH 35) was produced by magnetic stirring; chicken eggshell (ES) was added as cure improver. Thermal stability, cure parameters, mechanical properties, and fracture surface were investigated by thermogravimetry (TGA), differential scanning calorimetry (DSC), tensile experiments, and scanning electron microscopy (SEM). In general, the addition of ES slightly decreased the thermal stability, being T0.05 5% lower than that of the reference sample. The cure rate increased with the heating rates, while best results were obtained upon addition of neat membrane (M) from ES. Surprisingly, the mechanical properties were significantly improved with ES as well as with M, being the Young’s modulus 18% higher, the tensile strength 50% higher, and the deformation 35% higher than those of epoxy resin. SEM images showed that the synthetic compounds presented a smooth fracture surface, while the compounds with ES and M had a rougher surface with multiplane fractures, suggesting a fracture with higher energy absorption. In conclusion, epoxy/ES composites with better performance were produced, and effective tools are provided to control and attain in the future even better properties with ecological features.

Synthesis of Isophthalic Acid/Aluminum Nitrate Thin Film Nanocomposite Membrane for Hard Water Softening

In this study, nanocomposite was synthesized based on isophthalic acid/aluminum nitrate (CAU-10-H). The synthesized isophthalic acid/aluminum nitrate was studied using SEM, TEM, XRD, and FTIR. The thin film nanocomposite (TFN) nanofiltration membranes were constructed by interfacial polymerization of TMC and PIP using different loading of isophthalic acid/aluminum nitrate (0.005, 0.01, and 0.02). compared to the neat membrane for water softening, a significant improvement was observed in the water flux and multi ions (NaCl, MgCl2, MgSO4, Na2SO4).The highest of rejection Na2SO4 (94.70%) of the TFN membrane which the least water flux Na2SO4 was 32.72 L/m2 h at 6 bar.

Superior cross-linking assisted layer by layer modification of forward osmosis membranes for brackish water desalination

In this work, a novel surface modification strategy was developed to modify polyethersulfone membrane substrate to create membranes for forward osmosis applications. A novel poly(ethylenimine) crosslinked Hexadecafluorodecanedioic acid polyelectrolyte was synthesized, followed by layer deposition on the surface of an ultrafiltration membrane substrate. While the unmodified membrane was negatively charged, this procedure reversed the surface charge, leading to a positively charged forward osmosis-nanofiltration membrane. Interestingly, at pH 7, the zeta potential approached 6.9 mV for membrane coated 4.5 as compared to the pristine membrane with a zeta potential value of approximately −11.0 mV. Extensive characterization and chemical analyses were carried out to ensure the effectiveness of the developed separation layer. The results revealed that the poly(ethylenimine) crosslinked Hexadecafluorodecanedioic acid was successfully deposited on the polyethersulfone membrane substrate. Preparation conditions, such as curing temperature and time were optimized. It was found out that membrane coated with 3.5 bilayers and cured at 60 °C for one hour exhibited optimal water permeability of 21.9 L m−2 h−1 bar‐1 of and solute permeability of 1.66 L m−2 h−1 as compared to the neat membrane.

Effect of TiO2 loading on the morphology and CO2/CH4 separation performance of PEBAX-based membranes

Membranes have attracted much attention as economical methods for industrial chemical processes. The effects of the titanium dioxide nanoparticle load on the morphology and CO2/CH4 separation performance of poly (ether-block-amide) (PEBAX-1657) mixed matrix membranes (MMMs) were investigated from pressures of 3–12 bar and temperatures of 30°C–60°C. The PEBAX membranes were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis, atomic force microscopy and tensile strength analysis. The incorporation of TiO2 nanoparticles into the polymeric MMMs improved the CO2/CH4 gas separation performance (both the permeability and selectivity) of the membranes. The CO2 permeability and ideal CO2/CH4 selectivity values of the nanocomposite membrane loaded with 8 wt-% TiO2 were 172.32 Barrer and 24.79, respectively whereas those of the neat membrane were 129.87 Barrer and 21.39, respectively.

Nano Iron Oxide Impregnated Poly(Vinylidene Fluoride) Ultrafiltration Membrane for Palm Oil Mill Effluent Treatment

Palm oil mill effluent (POME) is highly organic loaded liquid waste in the palm oil industry. Membrane technology is preferred as the tertiary treatment due to the high removal efficiency and low space requirement. However, membrane fouling is the drawback of membrane technology, which increases the operational cost. Thus, the objective of this research is to improve the anti-fouling property of poly(vinylidene-fluoride) (PVDF) membrane by using nano - Fe3O4 as the additive. Nano - Fe3O4 was synthesized through chemical reduction method, and it was proved by the Energy Dispersive X-ray spectroscopy (EDX) spectrum. The nano iron oxide was added to the Poly(vinylidene-fluoride)/ Polyvinylpyrrolidone solution and cast into membranes. The hydrophilicity of nano - Fe3O4 modified the membrane surface and improved the antifouling property. This was proved by the lower contact angle of PVDF/ nano - Fe3O4 membranes (70.99°) compared to the neat membrane (77.13o ). PVDF/ nano - Fe3O4 membranes exhibited better separation performance compared to the neat membrane, especially in BOD removal. PVDF/nano iron oxide membrane removed 94.73% of BOD while 88.67% BOD was removed by the neat membrane. At the same time, the membranes exhibited consistent COD and TSS removal in the first 5 cycles in treating POME. A slight reduction in BOD removal was observed from the first cycle to the fifth cycle suggested the use of other membrane cleaning method is required to remove the foulants. In conclusion, nano - Fe3O4 improved the anti-fouling property of PVDF membrane, and a comprehensive 12 study on membrane cleaning shall be conducted in the near future for sustainable use.

Preparation and characterization of a novel high-flux emulsion polyvinyl chloride (EPVC) ultrafiltration membrane incorporated with boehmite nanoparticles

A novel high-flux emulsion polyvinyl chloride (EPVC) ultrafiltration membrane incorporated with different concentrations of boehmite nanoparticles was prepared. The modified EPVC membranes demonstrated enhanced hydrophilicity property and higher pure water flux and lower water contact angle because of the presence of hydrophilic boehmite in membrane matrix. The results showed that water flux was enhanced from 422.6Lm−2h−1 for neat membrane to 7014Lm−2h−1 for 0.75wt.% boehmite incorporated membrane at 2bar. In addition, BSA flux growth of the optimum nanocomposite membrane in comparison with the neat one was 37.2%. BSA rejection for all nanocomposite membranes was above 98%.

A hydrophilic-oleophobic chitosan/SiO2 composite membrane to enhance oil fouling resistance in membrane distillation

To develop an inexpensive and simple technology and increase anti-oil fouling resistance for membrane distillation applications, a hydrophilic/oleophobic nanocomposite membrane was fabricated by using SiO2/Chitosan (CT) sol solution coating with different volume ratios (0.5 : 1, 1 : 1 and 2 : 1 v/v) on PVDF membrane surface. The formation of SiO2/CT layer on membrane surface was confirmed by Fourier transform infrared (FTIR) spectroscopy and energy-dispersive X-ray spectroscopy (EDX). The influence of hydrophilic nanocomposite layer on the characteristics of membranes, including in-air water contact angle, morphology, porosity, liquid entry pressure of water (LEPw) and direct contact membrane distillation (DCMD) performance, was investigated. The results show that the composite membrane (SiO2/CT (1 : 1 v/v)- PVDF membrane) by adding of 0.5 and 1 g/L gasoline concentrations not only incurred fouling but also a higher flux with respect to the neat membrane in each gasoline concentration. During 8 hours continuous desalination process of saline gasoline emulsion solution (20 gr/L NaCl solution containing 0.5 gr/L gasoline), it was found that all modified membranes had high performance stability in comparison with the neat membrane, the modified membrane showed high performance stability and flux without decreased salt rejection (99.9%). At the end, we conducted performance comparison between the prepared membranes in current work and presser based process.

Swelling reduction of polyvinylidenefluoride hollow fiber membrane incorporated with silicoaluminophosphate-34 zeotype filler for membrane gas absorption

CO2 gas absorption is important in fuel purification and carbon capture. By incorporating a porous membrane with a large surface area in membrane gas absorption (MGA) system, the CO2 transfer between feed gas and liquid absorbent can be greatly improved. However, the absorption flux usually drops in the long-term operation due to membrane wetting by the common liquid absorbent, amine. Membrane wetting can lead to membrane swelling which induce the growth of mass transfer resistance. In this work, silicoaluminophosphate-34 (SAPO-34) zeolite was incorporated into polyvinylidene fluoride (PVDF) hollow fiber membrane to reduce flux decline caused by membrane swelling. The membrane porosity and pore size increased with increasing SAPO-34 loading. Nevertheless, significant changes in water contact angle or liquid entry pressure were not shown. PVDF hollow fiber membrane incorporated with 3 wt% of SAPO-34 showed slightly higher CO2 absorption flux to PVDF hollow fiber membrane in MGA with distilled water as the absorbent. However, the CO2 absorption flux of this PVDF/SAPO-34 membrane was greatly improved of about 140 % higher than the CO2 absorption flux of the neat membrane when diethanolamine was used as the absorption. The CO2 absorption flux of PVDF hollow fiber membrane dropped about 60 % after 96 hours. Although these membranes showed a similar water contact angle after being wetted by water or amine, they swelled differently. PVDF hollow fiber membrane swelled nearly 71.0 % after being wetted by amine, but only swelled about 2 % after being wetted by water. The incorporation of SAPO-34 into PVDF hollow fiber membrane reduced swelling by amine, down to 47.7 %. The swelling reduction could be a major cause of absorption improvement shown by PVDF/SAPO-34 hollow fiber membrane in MGA using diethanolamine.

Experimental Study of CO2 and CH4 Permeability Values Through PebaxⓇ-1074/Silica Mixed Matrix Membranes

In this research, mixed matrix membranes (MMMs) composed of poly(ether-block-amide) (PebaxⓇ-1074) and silica (SiO2) were prepared. Silica nanoparticles were distributed uniformly in the PebaxⓇ matrix without significant agglomerations and defects at the loadings of 0.0, 2.5, 5.0, 7.5 and 10 wt.%, confirming by field emission scanning electron microscopy (FESEM). Attenuated total reflection-Fourier transfer infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA) were also carried out to identify functional groups, crystalline structure and thermal stability of the prepared membranes, respectively. The incorporation of silica nanoparticles resulted in significant improvements in CO2 permeability and consequently ideal CO2/CH4 selectivity. At 10 wt.% loading of silica nanoparticles, the MMM exhibited the best separation performance with the CO2 permeability of 105.94 Barrer and CO2/CH4 selectivity of 26.09 which are significantly higher than the neat membrane properties.

Reactive modification of PVC membranes for the improved performance

Poly vinyl chloride (PVC) was chemically modified, and used for ultrafiltration to analyze the performance. Nonsolvent induced phase separation (NIPS) method was used to prepare membranes. The neat PVC membrane was casted and used as a control membrane. Modified membrane was prepared by reacting PVC with ethanolamine (EA) in the casting solution (labeled as CM-PVC). Pure water permeability (PWP) was evaluated by measuring pure water flux. Humic acid was used as model foulant solute to analyze flux and rejection ability of membranes. Flux and rejection data of neat and modified membranes were compared to prove the improvement in the filtration performance. The experimental results showed that for PVC and CM-PVC, PWP was calculated to be ~64 and ~143 L/m2.h, respectively, and the rejection of humic acid was found to be 98% and 100%, respectively. TGA was carried out to analyze the effect of chemical modification on the thermal stability of polymer. FT-IR analysis was another characterization technique used for the comparative study.

Enhanced mechanical properties of PDMS/PMMA composite membrane using MWCNTs and its application in phenol separation from saline wastewater

ABSTRACTThis work describes the enhanced mechanical properties of composite polydimethylsiloxane/poly(methyl methacrylate) (PDMS/PMMA)/multi‐walled carbon nanotubes (MWCNTs) nanofiber membrane and its application in the phenol separation from saline wastewater. MWNCTs with varied content were immobilized in the membrane matrix using electric field of electrospinning. The neat PDMS/PMMA and composite PDMS/PMMA/MWCNTs membranes were characterized by scanning electron microscopy, universal testing machine, contact angle measurement, 3D automatic optical profiler, and pore size analyzer. Results indicated that tensile strength of composite PDMS/PMMA/MWNCTs membrane was drastically increased six times with a water contact angle (WCA) of 163.3° due to increased roughness parameters compared to neat membrane. However, porosity and fiber diameter of PDMS/PMMA/MWCTs membrane decreased with the increase of MWCNTs content. Moreover, phenol extraction efficiency of PDMS/PMMA/MWNCTs membrane was found to be 34.5% higher than neat one with similar salt rejection efficiency of 99.97%. The stability of MWCNTs in the membrane matrix was confirmed by the cross‐sectional morphology, which indicated the robust and novel design of membrane. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47123.

Preparation and characterization of ultra-thin poly ether block amide/nanoclay nanocomposite membrane for gas separation

Supported Mixed Matrix Membrane (SMMM) Polyether block amide/nanoclay (PEBA/Cloisite 30b), based on Polyacrylonitrile on nonwoven Polyester (PAN/PE), was fabricated by the spin coating method, following optimization of fabrication conditions for Single-Layer Mixed Matrix Membranes (SLMMMs). Cloisite 30b is a type of montmorillonite modified from nanoclays family. The fabricated membranes were examined structurally through The X-ray Diffraction (XRD), The Field Emission Scanning Electron Microscopy (FESEM), The Fourier-transform infrared spectroscopy (FTIR), and The Atomic force microscopy (AFM) analyses, and evaluated operationally by conducting permeability tests of the pure gases of CO2, CH4 and N2. The effect of different Cloisite 30b loadings and the varying pressures on the gas separation performance of the membranes was investigated. Elevation of the loading up to 0.2 wt% Cloisite 30b increased the permeability and the selectivity, whereas further increase up to 1 wt% reduced the permeability and selectivity. After an increase in pressure from 4 to 14 bar, an elevated permeability and selectivity was observed. The membrane with a Cloisite 30b loading of 0.2 wt% had the best performance in the separation of the pure gases of CO2, CH4, and N2 such that the permeability of CO2, along with the selectivity of CO2/N2, and CO2/CH4 had increase of about 55.55%, 26.45% and 38% in comparison with the Single Layer Neat Membrane (SLNM). The permeability of CO2, the selectivity of CO2/N2, and the selectivity of CO2/CH4 of SMMM with a Cloisite 30b loading of 0.2 wt% also indicated an increase of about 364%, 18% and 47.8% in comparison to the Supported Neat Membrane (SNM). Furthermore, CO2 permeability through SMMM with cloisite30b loading of 0.2 wt% indicated a growth of about 562.5% in comparison to SLMMM with the same loading.

Hybridization of MWCNTs and reduced graphene oxide on random and electrically aligned nanocomposite membrane for selective separation of O2/N2 gas pair

This present study demonstrates the development of high-performance polysulfone (PSf) hybrid mixed matrix membranes (MMMs) through the collaborative inclusion of multiwalled carbon nanotubes (CNTs) and reduced graphene oxide (rGO). The nanofillers are aligned by virtue of an AC electric field in order to formulate a multifunctional composite membrane structure for selective separation of O2/N2 gas. Proper alignment of the conducting nanofillers within PSf was confirmed by utilizing different microscopy and spectroscopy techniques. Hybridization of CNTS and rGO resulted in concurrent enhancement of permeability as well as the selectivity of the neat membrane. The inclusion of rGO nanosheets established a long, tortuous path hindering the permeation of gas molecules possessing the larger molecular size, while CNTs-filled MMM achieved better permeation due to their favorable intrinsic structural characteristics. The overall performance of the aligned hybrid membranes was found to be significant in contrary to single filler-based membrane systems (PSf/CNTs and PSf/rGO).

Amine wetting evaluation on hydrophobic silane modified polyvinylidene fluoride/silicoaluminophosphate zeolite membrane for membrane gas absorption

Membrane wetting in membrane gas absorption is undesirable as it reduces the gas transfer in wet pores. This work aims to understand the improvement of membrane hydrophobicity using fluoroalkyl silane and its effects on membrane properties, separation performance and membrane wetting by amine. Polyvinylidene fluoride/silicoaluminophosphate zeolite membranes were prepared using non-solvent induced phase separation technique and then immersed into a mixture of (3,3,3-trifluoropropyl) trimethoxysilane and ethanol solution (volume ratio of 1: 100) for 20 min. The post-modification resulted in a slight improvement of water contact angle and liquid entry pressure. Hence, the highest CO2 absorption flux of 4.48 ± 0.36 × 10−4 mol.m−2. s−1 was achieved using silanated membrane, about 25 % of improvement in comparison to the neat membrane. The absorption flux of humid gas was slightly reduced (-16 %) due to pore wetting. Fluoroalkyl silane could be used to prevent water wetting, resulting improvement of CO2 absorption. The membranes were immersed in diethanolamine solution (2 M) for 50 h before characterization using goniometer, Fourier transform infrared spectroscopy and scanning electron microscope. The incorporation of zeolite reduced membrane wetting because membrane swelling could be prevented. The unfavorable interaction between fluoroalkyl and amine groups induced severe membrane wetting by amine.

Highly thin film nanocomposite membrane based metal organic complexes for brackish water desalination

Recently metal organic frameworks MOFs incorporated thin film composite membranes had great attention in separation processes due enhancement porosity with excellent selectivity.In this work, binary and ternary complexes as a green metal organic framework were successfully prepared using carboxymethyl cellulose as a cluster organic linker. The two types of MOFs were embedded with different loading amount in the selective layer through interfacial polymerization. The prepared meso-fillers MOFs were characterized by SEM, FTIR and EDX. Also the membranes were characterized by SEM and separation assessments. The Results showed that the optimum loading MOFs was 0.1 wt%. Both binary complex MOF1 and ternary complex MOF2 were enhanced the performance of the membrane and the impact was depended on the MOFs loading amount. At the optimum MOFs loading amount 0.1 wt.%, the permeate flux increased from 30 LMH to 36 and 41 LMH, for the neat membrane, MOF1 and MOF2 membranes respectively. As well NaCl rejection was significantly affected and improved by embedding these MOFs, where NaCl rejection increased from 69% to 93% and 97% for neat membrane, MOF1 and MOF2 membranes respectively to 7000 ppm of NaCl at 5 bar feed pressure. The prepared membranes based MOF1 and MOF2 with 0.1 wt.% were tested for 60 days to confirm the stability of polyamide layer and their performance properties. The cubic like structure for the polyamide layer was observed by SEM images for 0.1% ternary complexes filled membrane so this study demonstrates that the MOFs based membrane is a promising technology on the laboratory mode for water desalination.

Gas transport and mechanical properties of PDMS-TFS/LDPE nanocomposite membranes

This study investigates the effect of trimethylsiloxy fumed silica (TFS) on the mechanical and gas permeation properties of polymer nano-composite membranes. The membranes were produced by coating TFS incorporated polydimethylsiloxane (PDMS) at different loadings (5, 10 and 15 wt.%) on a porous low density polyethylene (LDPE) substrate which was formed by a melt-extrusion/salt leaching technique. The PDMS-TFS/LDPE membranes were characterized by SEM, TGA and DMTA. The results showed that good affinity between the PDMS treated TFS particles and PDMS matrix was obtained leading to improved mechanical and thermal properties. For gas permeation, CH4 and C3H8 at different upstream pressure (50 to 80 psig) and temperature (27 to 55 °C) were investigated. The results showed that the C3H8/CH4 ideal selectivity (17.6) and C3H8 permeability (1.89 × 104 Barrer) through 10 wt.% TFS loaded membranes (PDMS-TFS10%/LDPE) were 41 and 14% higher than the neat membranes (PDMS-TFS0%/LDPE), respectively. The permeation results also indicate that the performance stability under the conditions investigated makes PDMS-TFS/LDPE membranes interesting for industrial applications.

Investigation of structure‐performance properties of a special type of polysulfone blended membranes

Membranes require superior mechanical strength due to applied harsh conditions. The mechanical properties of membranes decrease with increasing hydrophilicity of its elements. In this study, mechanical properties were investigated for two special blended membranes which were made by blending polysulfone with (polysulfone‐g‐poly (n‐butylacrylate) and polysulfone‐g‐poly (tert‐butylacrylate) as components. All of the prepared membranes were characterized by differential scanning calorimeter, thermal gravimetric analysis, field emission scanning electron microscope, and atomic electron microscope and were investigated in terms of pure water flux, water contact angle, molecular weight cut off, and morphology. It was found that water contact angle decreased from 73.6° which belongs to neat membrane decreased to 46° for blended membranes containing higher amounts of copolymers; however, the pure water flux increased with increasing copolymer content considerably compared with the neat membrane. Also, molecular weight cut off increased aggressively. Furthermore, mechanical properties including tensile strength, Young modulus, and elongation at break were measured and compared with the neat polysulfone membrane. Results showed that the tensile strength and modulus decreased with an increase in the copolymers content, despite the increase in the elongation at break. The effect of applied pressure on the membrane structure and also bursting strength were studied, and it has been proved that not only the structure of the membranes but also their performance is strongly affected by the composition of the membranes.

Fabrication, characterization, and performance evaluation of polyethersulfone/TiO2 nanocomposite ultrafiltration membranes for produced water treatment

In the present work, development of neat and nanocomposite polyethersulfone membranes composed of TiO2 nanoparticles is presented. Membranes are fabricated using nonsolvent phase inversion process with the objective of improving antifouling, hydrophilicity, and mechanical properties for real and synthetic produced water treatment. Membranes are characterized using scanning electron microscopy, Fourier‐transform infrared, contact angle, porosity measurement, compaction factor, nanoparticles stability, and mechanical strength. The performance of prepared membranes was also characterized using flux measurement and oil rejection. Fourier‐transform infrared spectra indicated that noncovalence bond formed between Ti and polyethersulfone chains. The contact angle results confirmed the improved hydrophilicity of nanocomposite membranes upon addition of TiO2 nanoparticles owing to the strong interactions between fillers and water molecules. The increased water flux for nanocomposite membranes in comparison with neat ones can be due to coupling effects of improved surface hydrophilicity, higher porosity, and formation of macrovoids in the membrane structure. The membrane containing 7 wt% of TiO2 nanoparticles was the best nanocomposite membrane because of its high oil rejection, water flux, antifouling properties, and mechanical stability. The pure water flux for this membrane was twice greater than that of neat membrane without any loss in oil rejection. The hydrophilicity and antifouling resistance against oil nominates developed nanocomposite membranes for real and synthetic produced water treatment applications with high performance and extended life span.