Influence of compatibility between sol and intermediate layer on the performance of yttria-stabilized zirconia nanofiltration membrane

This paper reports the synergistic effect of the sol and intermediate layer on the performance of yttria-stabilized zirconia (YSZ) nanofiltration (NF) membranes. We have focused on the characterization of the microstructure, pure water permeance, and molecular weight cut-off (MWCO) of the NF membranes derived from zirconia sols of different precursor concentrations on two types of supported ZrO₂ ultrafiltration (UF) membranes. We found that the performance of YSZ membranes strongly depends on the sol concentration and the pore size of the intermediate layer. In addition, YSZ gel membrane formation was found to follow the filtration process. Therefore, it is essential to maintain the compatibility between the sol and intermediate layer to fabricate high-performance NF membranes. A crack-free thin YSZ layer with an MWCO of 816 Da (pore size: 1.4 nm) and a water permeance of 25 L m^-2 h^-1 bar^-1 was fabricated using a precursor concentration of 0.03 mol/L, on ZrO₂ UF membrane with a pore size of 5.5 nm. The YSZ NF membrane exhibited a relatively high retention rate towards MgCl₂ (71%), whereas a lower retention rate was observed for NaCl (35%).     

Corrosion resistant ZrO2/SiC ultrafiltration membranes for wastewater treatment and operation in harsh environments

This work focused on the fabrication of a ZrO₂/SiC ultrafiltration membrane by dip coating a high porous SiC support with a ZrO₂ slurry prepared by ceramic processing. The membranes were sintered in different temperatures (1000−1300 °C). With the optimal temperature, it was obtained a mechanically strong, homogenous, and defect free separation layer with 45 μm of thickness and average pore size of 60 nm. A pure water permeability of 360 L.m⁻² h⁻¹ bar^-1 and high retentions of humic acid, indigo dye, and hemoglobin were observed. In a pilot test with an olive oil/water emulsion, 99.91 % of oil was removed without fouling. Long-term corrosion tests at basic and acid baths did not cause change in pore size and morphology. In conclusion, the ZrO₂/SiC membrane has potential to operate in harsh conditions (e.g. heavily contaminated industrial effluents or urban wastewaters) and when severe membrane cleaning and disinfection are required, such as food and pharmaceutical industries.     

Preparation and characterization of Al3+-doped TiO2 tight ultrafiltration membrane for efficient dye removal

Al³⁺-doped TiO₂ (AT) tight ultrafiltration membrane with stable anatase phase was prepared by a modified sol-gel process using butyl titanate and aluminum chloride as the precursor and aluminum source respectively. The removal of Alizarin red-S was investigated by filtration experiment. A dip-coating process on homemade flat Al₂O₃ intermediate layer by TiO₂ sol followed by heat treatment was adopted to obtain the desired AT membrane. The addition of Al³⁺ inhibits the phase transformation of nanosized TiO₂ from anatase to rutile and restrains the growth of crystallite, resulting in the pore size of the separation layer reducing to 3.5 nm. The prepared AT1-500 membrane exhibits enhanced hydrophilicity with no cracks or pinholes, and shows a water permeability of 9.6 L m^-2 h⁻¹ bar⁻¹ and cut-off molecular weight (MWCO) of 4650 Da. The membrane demonstrated a retention rate of 96.9% for Alizarin Red-S (250 ppm) and maintained almost constant under repeated using.     

Preparation of yttria-stabilized ZrO2 nanofiltration membrane by reverse micelles-mediated sol-gel process and its application in pesticide wastewater treatment

8 mol% yttria-stabilized ZrO₂ (8YSZ) nanofiltration (NF) membranes were prepared from size-controlled spherical ZrO₂ nanoparticles with an average diameter of ˜10 nm and a particle roundness value greater than 0.90, and the nanoparticles were efficiently fabricated by a reverse micelles (RMs)-mediated sol-gel process. It was found that yttria doping not only suppressed the tetragonal to monoclinic (t-m) phase transition, ensuring the membranes integrity, but also decreased the tetragonal grain size, increased the specific surface area, narrowed the pore size distribution and thus optimized the NF performance. The as-prepared 8YSZ NF membranes with a thickness of ˜260 nm exhibited high NF performances, while the pure water permeability and molecular weight cut-off (MWCO) were 3.9-4.2 L m⁻² h^-1 bar^-1 and 800 ± 50 Da respectively. In the treatment of pesticide wastewater, the removal rate of carbofuran by 8YSZ NF membranes was more than 82%, while the maximum removal rate could reach 89%. Furthermore, the contaminated membranes could be restored as ever after alkali wash and low-temperature calcination, implementing multiple reuses.     

Perforative pore formation on nanoplates for 2D porous MXene membranes via H2O2 mild etching

MXene (Ti₃C₂T_x) is a novel, two-dimensional (2D) layered material that is atomically thin, exhibits good mechanical strength, and is ideal for fabricating efficient membranes for molecular separation. However, the applications of MXene membranes are limited by their low water permeability owing to narrow channels and high tortuosity. A novel strategy for introducing artificial pores on the surface of MXene nanosheets via gentle in situ chemical etching with hydrogen peroxide (H₂O₂) to prepare porous MXene nanosheets (PMS) is reported herein. This greatly increases the water permeability of MXene membranes while retaining the high rejection of small-molecule dyes. Permeable pores generated on MXene nanosheets transform the transport model of water molecules in the membrane from typical horizontal transport pathways dominated by interlayer channels to longitudinal–lateral three-dimensional transport pathways, affording increased water molecule transport channels and reduced transport distance. Based on different etching conditions, the obtained membranes exhibit high pure-water permeability ranging from 9.37 to 42.48 L m⁻² h⁻¹ bar⁻¹. Moreover, mild etching maintains the 2D structure of the membrane and retains a nearly complete rejection of congo red dye. This study provides a novel and effective strategy for preparing high-performance porous laminar MXene membranes for dye-separation applications.     

Recycling of waste attapulgite to prepare ceramic membranes for efficient oil-in-water emulsion separation

Large-scale application of ceramic membranes is restricted by high cost resulting from raw materials and sintering process. In this study, low-cost ceramic membranes were prepared with waste attapulgite (WAT) and α-Al₂O₃ as starting materials and used for oily wastewater treatment. The optimal membrane sintered at 1100 °C possessed excellent properties, with open porosity of 41.6%, flexural strength of 37.2 MPa and average pore size of 0.40 μm. The membrane also displayed outstanding permeability and chemical stability. The hydrophilicity and underwater oleophobicity were enhanced after surface modification. When used for oil-in-water emulsion filtration, the permeate flux reached 236.8 L m^?2 h^?2 bar^-1 under a low transmembrane pressure of 0.2 bar and the oil rejection exceeded 99%. Membrane cleaning with a simple ultrasonic treatment could easily achieve flux recovery. This study proposed a feasible strategy for both solid waste utilization and oily wastewater treatment.     

Preparation of poly(ether sulfone) hollow fiber UF membrane for removal of NOM

In this study, a high performance poly(ether sulfone) (PES) hollow fiber ultrafiltration (UF) membrane has been prepared for removal of natural organic matter (NOM). The membrane was spun from a dope solution containing PES/poly (vinyl pyrrolidone) (PVP 40K)/N‐methyl‐2‐pyrrolidone (NMP) by using a wet‐spinning process. Characterization of the membrane in terms of pure water flux, molecule weight cut‐off (MWCO), and retention for a model humic acid (HA) were conducted, and the fouling resistance was analyzed. The experimental results showed that the membrane had a pure water permeability of 20 × 10^?5 L m^?2 h^?1 Pa^?1 and a nominal MWCO of 6000 Da. The results also showed that the membrane retention for humic acid was over 97% and both productivity and selectivity for HA increased with increasing feed velocity. The PES membrane in this study exhibited a much lower fouling tendency than the commercial polysulfone membrane. SEM images revealed that the membrane had an outer dense skin and a porous inner surface. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 430–435, 2006     

Potential of DMSO as greener solvent for PES ultra‐ and nanofiltration membrane preparation

In this article, the performance of polyethersulfone (PES) ultra‐ and nanofiltration membranes, prepared with the non‐toxic solvent dimethyl sulfoxide (DMSO), was investigated. The membranes were prepared by immersion precipitation via phase inversion. Experimental results proved that DMSO is a better alternative to N‐methyl‐2‐pyrrolidone (NMP) as solvent for PES ultrafiltration membranes as the membranes had a higher permeability and rejection of bovine serum albumin (BSA). An explanation was found based on experimental cloud point data and scanning electron microscopy images showing the morphology. The rejection of BSA and rose Bengal (RB) was proportional to the polymer concentration. On the contrary, the permeability decreased with increasing polymer concentration. For a casting thickness of 250 µm, an optimal balance between permeability and rejection of macromolecules for ultrafiltration was found at 24 wt % PES. The permeability was inversely proportional to the casting thickness, but a small decrease in rejection was observed when lowering the thickness. A good balance between permeability and rejection of RB was found, using a reference nanofiltration membrane of 28.5 wt % PES with 150 µm casting thickness. This membrane achieved a RB rejection of 95.3% and a pure water flux of 2.03 L m^?2 h^?1 bar^?1. The membrane thickness and polymer concentration did not have a clear influence on the hydrophilicity of the membranes. It can be concluded that DMSO is a benign alternative as compared to traditional solvents such as NMP and also results in better PES membrane performances. DMSO is a perfectly suitable solvent for ultrafiltration applications and has potential to be used for nanofiltration applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46494.     

Novel high performance hollow fiber ultrafiltration membranes spun from LiBr doped solutions

The objective of this research is to evaluate the performance of the polyethersulfone (PES) hollow fiber ultrafiltration membranes spun from LiBr doped solutions prepared using the newly developed microwave heating technique. In addition the resultant hollow fiber membranes were introduced to a new post-treatment method where the membranes were placed in water and irradiated using the microwave technique. Various concentrations of the additive, LiBr, (1-4 wt.%) were added into the PES dope solutions. The dissolution of PES and LiBr in DMF was facilitated by the microwave heating technique. The performance of the membranes was evaluated in terms of pure water permeation and polyethylene glycol separation and its molecular weight cutoff (MWCO) was determined. The results revealed that the microwave post-treatment technique was proven to be effective in producing higher performance membranes. The best performance was obtained at 3% LiBr with MWCO at 90% rejection in the range of 2.83 kDa and high flux range of 222.18 (Lm^− 2 h^− 1 bar^− 1). LiBr interacts in the membrane matrix resulting in the enhancement of the hydrophilic property of the membrane and this is confirmed by the contact angle measurement.     

High permeability poly(vinylidene fluoride) ultrafiltration membrane doped with polydopamine modified TiO2 nanoparticles

In order to improve the water permeability of poly(vinylidene fluoride) (PVDF) ultrafiltration (UF) membranes with low molecular weight cut-off (MWCO), polydopamine (PDA) was employed in the membrane preparation process. Owing to its merits of material-independent adhesion, PDA was coated on inorganic particles or added in coagulation bath to tailor the final membrane structure and property. The introduction of PDA broke through the permeability/selectivity trade-off of the PVDF membrane. By adding the PDA coated titanium dioxide (PDA/TiO₂) nanoparticles, water flux increased by 287% while MWCO kept similar with the pristine PVDF membrane. Thermodynamics and Kinetics of the PVDF/additives/non-solvent were analyzed and shown that nanoparticles reduced the thermodynamic stability and increased the phase separation speed, and the speed can be adjusted using different nanoparticles. Additionally, X-ray diffraction (XRD) test indicated that PVDF crystalline form changed from α phase to β phase after adding different nanoparticles. Permeability/selectivity trade-off was broken through by DA addition in coagulation bath. Compared with the original PVDF membrane, when the DA concentration of the coagulation bath was 2.0 g·L⁻¹, water flux increased by 312%, and MWCO of the PVDF membrane ranged in 10,000 to 20,000 Da as well as contact angle decreased from 81.4° to 45°.     

Preparation and characterization of a novel positively charged nanofiltration membrane based on polysulfone

The goal of this study was to prepare positively charged nanofiltration (NF) membranes to remove cations from aqueous solutions. A composite NF membrane was fabricated by the modification of a polysulfone ultrafiltration support. The active top layer was formed by the interfacial crosslinking polymerization of poly(ethylene imine) (PEI) with p‐xylene dichloride (XDC). Then, it was quaternized by methyl iodide (MI) to form a perpetually positively charged layer. The chemical and morphological changes of the membrane surfaces were studied by Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy. To optimize the membrane operation, the PEI solution concentration, PEI coating time, XDC concentration, crosslinking time, and MI concentration were optimized. Consequently, high water flux (5.4 L m^?2 h^?1 bar^?1) and CaCl₂ rejection (94%) values were obtained for the composite membranes at 4 bars and 30°C. The rejections of the NF membrane for different salt solutions, obtained from pH testing, followed the order Na₂SO₄ < MgSO₄ < NaCl < CaCl₂. The molecular weight cutoff was calculated by the retention of poly(ethylene glycol) solutions with different molecular weights, and finally, the stoke radius was calculated as 1.47 nm. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41988.     

Asymmetric TiO2 hybrid photocatalytic ceramic membrane with porosity gradient: Effect of structure directing agent on the resulting membranes architecture and performances

Asymmetric TiO₂ hybrid photocatalytic ceramic membranes with porosity gradient have been fabricated via acid-catalyzed sol–gel method. Different structure directing agents (SDAs) i.e. Pluronic P-123, Triton X-100, Tween 20 and Tween 80 were incorporated in the preparation of TiO₂ sol to obtain a porous multilayered TiO₂ coated on the alumina ceramic support. Six different SDA-modified membrane specimens were fabricated. Four of which were coated with the TiO₂ sols prepared using only one type of SDA. The remaining two specimens were fabricated via multilayer coating of different TiO₂ sols prepared using different types of SDAs. Physico-chemical and morphological properties of different TiO₂ layers were thoroughly investigated. The membrane M1 which had the most porous TiO₂ sub-layers showed a high pure water permeability of 155 L m⁻² h⁻¹ bar⁻¹. The membrane showed a relatively high Rhodamine B (RhB) removal of 2997 mg m⁻² over 8 h treatment duration in the batch photoreactor, second only to the Pluronic-based TiO₂ membrane (specific RhB removal of 3050 mg m⁻²). All membrane specimens exhibited good performances while operated in the flow-through photocatalytic membrane reactor. Over 91% of RhB removal capability was retained after 4 treatment cycles. All membranes also showed self-cleaning property by retaining >90% of initial flux after 4 treatment cycles. The flexibility of optimizing membrane performances by fine-tuning the porosity gradient configuration of the photocatalytic layer has also been demonstrated.     

Reaction-bonded robust SiC ceramic membranes sintered at low temperature with coal gangue

Herein, we report an in-situ reaction-bonded SiC membrane sintered at low temperature using a solid waste (i.e. coal gangue) as the sintering aid to form strong neck connections. The effects of sintering temperature and coal gangue proportion on their properties regarding pore size, open porosity, bending strength and pure water permeability were investigated. The single-channel tubular SiC membrane sintered at 1300 °C with a coal gangue proportion of 12 wt% was optimal, exhibiting an average pore size of 2.78 μm, a open porosity of 47.08%, a bending strength of 34.01 ± 1.3 MPa and a high water permeability of 83967 L m⁻² h⁻¹ bar⁻¹. The membrane could completely reject D₅₀ = 0.87 μm SiC solids and presented a steady-state water permeability of 458 L m⁻² h⁻¹·bar⁻¹. The SiC membrane could be regenerated through ultrasonication and its steady-state water permeability was almost unchanged for 3 cycles, proving its mechanical robustness. This work may appeal to the practical low-cost production of high-performance SiC membranes.     

Green and feasible fabrication of loose nanofiltration membrane with high efficiency for fractionation of dye/NaCl mixture by taking advantage of membrane fouling

Loose nanofiltration membrane emerges as required recently, since it is hard for conventional nanofiltration membrane to fractionate mixture of dyes and salts in textile wastewater treatment. However, the polymeric membranes unavoidably suffer from membrane fouling, which was caused by the adsorption of organic pollutants (like dyes). Normally, the dye fouling layer will shrink membrane pore size, thus resulting in flux decline and rejection increase. It is thought that membrane fouling may be a double-edged sword and can be an advantage if properly utilized. Thereby, loose nanofiltration membranes were constructed here by a green yet effective method to fractionate dyes/salt mixture by taking advantage of membrane fouling without using poisonous ingredients. A commercially available polyacrylonitrile (PAN) ultrafiltration membrane with high permeability was chosen as the substrate, and dyes were used to contaminate PAN substrate and formed a stable barrier layer when adsorption of dyes reached dynamic equilibrium. The resultant PAN-direct red 80 (DR80) composite membranes displayed superior permeability (~128.4 L m⁻² h⁻¹) and high rejection (~99.9%) to DR80 solutions at 0.4 MPa. Moreover, PAN-DR80 membranes allowed fast fractionation of dyes/sodium chloride (NaCl) mixture, which maintained a negligible dye loss and a low NaCl rejection (~12.4%) with high flux of 113.6 L m⁻² h⁻¹ at 0.4 MPa. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47438.     

Preparation and characterization of new tubular kaolino-illitic ceramic membrane used for dairy wastewater treatment

Low cost asymmetric tubular ceramic membrane was developed from kaolino-illitic clay collected from the region of Medenin (Tunisia). The obtained membrane was designed to be used for ultrafiltration. The effect of pore forming agent on the plasticity, porosity, pore size distribution, mechanical strength, and permeability was evaluated. The support was performed by extrusion using the raw clay and olive pomace (OP) as pore forming agent. The effect of the use of OP was noticeable; it improved the plasticity of the paste. Also it helped to ameliorate both permeability and porosity of the obtained supports. Top layer was prepared using acid activated clay suspension. The obtained membrane had gas permeability of about 13 cm³.s⁻¹.cm⁻².bar⁻¹ at a pressure of 1.5 bar and water flux of 1700 L.h⁻¹.m⁻² at a pressure of 1 bar. The final membrane was successfully used to eliminate the fat present in a solution containing 10% of milk. Regeneration of the used membrane was carried out by calcination at 550°C. The performances of the used membrane were recovered by 97% after regeneration.     

Dye removal from colored textile wastewater using acrylic grafted nanomembrane

In this paper, the dye removal ability of the acrylic grafted polysulfone nanomembrane using ultraviolet radiation was studied to remove dyes from colored textile wastewater. Acrylic acid was used to modify polysulfone ultrafiltration membrane. The effect of different operating parameters such as pressure, salt concentration and chemical structure of dyes was evaluated. Data indicated that the photografted membrane has acceptable performance both in terms of flux and rejection. The dye rejection and hydraulic permeability were 86–99.9% and 7.6 L m^{− 2} h^{− 1} bar^{− 1}, respectively. It was found that the rejection of dyes decreased with salt concentration due to a decrease of the Donnan effect. Also, the low molecular weight dyes and highly charged dyes were more sensitive in the presence of salts. Addition of 80 mM Na₂SO₄ in dye solution decreased the dye rejection more than 15%. The rejection enhancement for all cases was negligible by increasing driving pressure from 1 to 4 bar. Dyes with low charger were more sensitive to operating pressure than that of dyes with higher charges. All findings supported that acrylic grafted nanomembrane is potentially capable to separate dyes from colored textile effluent.     

Development of a high-performance polysulfone hybrid ultrafiltration membrane using hydrophilic polymer-functionalized mesoporous SBA − 15 as filler

A novel polysulfone hybrid ultrafiltration membrane was developed by blending hydrophilic poly[poly(ethylene glycol) methyl ether methacrylate] [P(PEGMA)] grafted mesoporous SBA-15 [SBA-g-P(PEGMA)] as filler. The hydrophilic SBA-g-P(PEGMA) fillers were synthesized via surface-initiated atom transfer radical polymerization. The effects of the SBA-g-P(PEGMA) fillers on the prepared hybrid membranes were systematically investigated. Compared with pristine SBA-15 fillers, SBA-g-P(PEGMA) fillers contributed to higher hydrophilicity and a more developed pore structure in the hybrid membranes. Specifically, SBA-15 grafted with a moderate P(PEGMA) molecular weight could better preserve the valid open-ended filler pore structure in the membrane matrix, thus facilitating membrane permeability. The pure water flux of the as-prepared polysulfone (PSF)/SBA-g-P(PEGMA) membrane was three times that of the PSF/SBA-15 membrane (271.7 L m⁻² h⁻¹ vs. 88.2 L m⁻² h⁻¹) with similar membrane selectivity. Moreover, the PSF/SBA-g-P(PEGMA) membranes showed improved antifouling property. This work paves the way for developing high-performance hybrid membranes by blending of hydrophilic polymer-functionalized mesoporous fillers in the future. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47353.     

Catalytic template assisted interfacial polymerization for high-performance acid-resistant membrane preparation

Highly permeable acid-resistant nanofiltration (NF) membranes are of critical significance for the efficient treatment of acidic streams. Enhancing permeability while maintaining the high solute rejection of acid-resistant NF membranes remains a great challenge due to the low reactivity of monomers. In this work, a novel catalytic template assisted interfacial polymerization (IP) strategy of 3-aminobenzenesulfonamide (ABSA) and trimesoyl chloride (TMC) was provided to prepare a poly(amide-sulfonamide) membrane. Aminopyridine doped graphene quantum dots rich in acylation catalytic sites and ZIF-8 nanoparticles are co-loaded on a substrate as template. Benefiting from the enhanced phase integrity and self-inhibition effect of the template assisted IP process, the resulting ultra-thin acid-resistant membrane exhibits an excellent water permeance (20.4 Lm⁻²h⁻¹bar⁻¹) with a high Na₂SO₄ rejection of 90.5%, which outperforms almost all the reported acid-resistant NF membranes. Our work paves a versatile way for synthesis of special separation membranes.     

Effect of rheological properties of AlOOH sol on the preparation of Al2O3 nanofiltration membrane by sol-gel method

In order to directly prepare an High Flux Al₂O₃ nanofiltration membrane on an Al₂O₃ support with an average pore size of 4 μm, AlOOH sol was prepared with aluminum isopropoxide as the precursor, The effect of rheology on the dip-coating of AlOOH sol and the effect of viscoelasticity on the heat treatment of AlOOH gel film to prepare defect-free Al₂O₃ nanofiltration membrane were studied. The results indicate that AlOOH sol will increase its viscosity with the increase of the standing time. When the viscosity increases to a certain extent, the colloidal particles will gradually transform into gels, and change from Bingham fluid to Herschel-Bulkley pseudoplastic fluid. The thickness of the AlOOH gel film is related to the viscosity of the AlOOH sol. The flow viscosity of AlOOH sol should be about 0.0025～0.005 Pa·s, while the thickness of the AlOOH gel film after dip-coating is about 6.5～12 μm. The storage modulus and loss modulus of AlOOH gel film increase with the increase of aging time. Only when the storage modulus of the AlOOH gel is greater than the saturated vapor pressure of the solvent under normal pressure (0.1 MPa), it will not crack due to the evaporation of the sol during the heat treatment process. After the storage modulus exceeds 0.1 MPa, the surface of the heat-treated Al₂O₃ ceramic membrane is smooth and crack-free, the rejection rate for crystal violet dye is 99.8%, and its average pore size is 2.75 nm, that has the capability of nanofiltration. Due to the lack of intermediate layer, the pure water flux of the Al₂O₃ nanofiltration membrane is as high as 201.7 l.m^-2bar^-1h^-1, and the steady-state filtration flux is 48.7 l.m^-2bar^-1h^-1 when filtering 20 mg/l crystal violet solution. By controlling the rheological properties of AlOOH sol, a high flux Al₂O₃ nanofiltration membrane was prepared.     

High‐performance composite nanofiltration membranes fabricated via ternary mixture: Complementary preponderance of the fluorine‐containing monomer 2,2′‐bis(1‐hydroxyl‐1‐trifluoromethyl‐2,2,2‐triflutoethyl)‐4,4′‐methylene dianiline and the rigid monomer bisphenol F

In a previous study, we proved that tailoring the polyamide backbone stiffness is an effective way to fabricate high‐performance polyamide nanofiltration (NF) membranes. However, in the previous study, we mainly focused on the flat membrane and did not consider its chlorine tolerance. In this study, by regulating the aqueous‐phase compositions in the interfacial polymerization process, chlorine tolerance on NF hollow‐fiber membranes was endowed while the membrane performance stayed high. The experimental results show that when the ratio of Piperazine (PIP)–bisphenol F (BPF)/2,2′‐bis(1‐hydroxyl‐1‐trifluoromethyl‐2,2,2‐triflutoethyl)‐4,4′‐methylene dianiline (BHTTM) was 5:1:4, the NF membrane possessed a permeate flux of 21.0 L m^?2 h^?1 bar^?1 and an Na₂SO₄ rejection up to 90.0%. X‐ray photoelectron spectroscopy analysis also confirmed that the polymerization degree of the PIP–BPF–BHTTM NF membrane was the highest. Moreover, the NF membrane could tolerate active chlorine to over 10,000 ppm h Cl. After the active chlorine treatment, the permeate flux increased over 30.0 L m^?2 h^?1 bar^?1, and the Na₂SO₄ rejection was about 90.0%. Although the PIP–BHTTM NF membrane also possessed good chlorine tolerance, its permeate flux (after active chlorine treatment) was only 60% of that of the PIP–BPF–BHTTM NF membrane. Therefore, the PIP–BPF–BHTTM NF membrane possessed a combination of high flux and high chlorine tolerance and showed good potential in water treatment in rigorous environments. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46482.