Polysulfone Hollow Fiber Membranes Research Articles

Continuous renal replacement therapy with vitamin E-coated polysulfone hemofilter reduces inflammatory responses in a porcine lipopolysaccharide-treated model.

Biological invasions may promote the onset of systemic inflammatory response syndrome in patients eligible for continuous renal replacement therapy (CRRT), leading to poor prognosis. Hence, we aimed to examine the inflammatory reactions in circulation using vitamin E-coated polysulfone hollow fiber membrane (ViLIFE). Lipopolysaccharides were intravenously administered to pigs (2 μg/kg/30 min) to establish an acute inflammation model. Extracorporeal circulation was performed for 6 h in continuous venovenous hemodiafiltration mode using a hemofilter for CRRT filled with a polysulfone hollow fiber membrane or ViLIFE, and the differences in inflammatory reactions were evaluated. The ViLIFE group exhibited low platelet and cytokine levels (p < 0.05 vs. sham-CRRT group). Additionally, the ViLIFE group had lower lactate and high mobility group box 1 levels than the other groups. ViLIFE represents a promising CRRT modality that can inhibit the inflammatory response in circulation and inhibit further biological invasions.

Biogas purification by CO2 removal using facilitated transport mechanism of cellulose nanocrystals/polyvinyl alcohol layered hollow fiber membranes

AbstractBiogas can be a viable solution for replacing the conventional fuel for reducing pollution. However, the high CO2 content in biogas must be removed for its utilization. In this study, biogas purification is carried out employing cellulose nanocrystals (CNC)/polyvinyl alcohol (PVA) “selective layered” polysulfone hollow fiber membrane. The membrane chamber is designed such that the cross‐flow of the biogas can be ensured for the effective interaction of the biogas with membrane surface. From various characterization tools like field emission scanning electron microscope, FTIR, X‐ray diffraction, moisture absorption and tensile test, CNC1/PVA (1 wt% of CNC in PVA) nanocomposite film demonstrated optimum crystallinity and mechanical strength while retaining higher moisture absorption. The average selective layer thickness at this CNC concentration is 1169 nm. CO2 permeability of 17,858 barrer and the selectivity of 19 for CO2 over CH4 is observed, respectively.

Effect of Oxidants in the Utilization of Polysulfone Hollow Fiber Membrane Module as Bubble Reactor for Simultaneously Removal of NOx and SO2

Effect of Oxidants in the Utilization of Polysulfone Hollow Fiber Membrane Module as Bubble Reactor for Simultaneously Removal of NOx and SO2

Janus polysulfone gradient hollow fiber membranes with interfacial photothermal evaporation by optimization of water transport and thermal management

Interfacial solar evaporation is a promising technology to get fresh water from seawater, because it is free of fossil fuel consumption and carbon dioxide emission. Here, a Janus gradient polysulfone hollow fiber membrane (PSF HFM) with capillary force-driven water transport and 3D evaporation performance was constructed. Different from the traditional 3D evaporation architecture, internal water transport and external water vapor are generated simultaneously. Especially, the outer surface of the membrane can also effectively absorb heat from the environment for cold evaporation because its temperature is lower than the ambient temperature. The obtained 3D PSF HFMs showed a light absorption rate of 93.7 % under simulated sunlight, and an evaporation rate of 2.51 kg·m−2·h−1 under one sun at an ambient temperature of 25 ℃. The evaporation rate of 1.6 kg·m−2·h−1 could be obtained in simulated seawater. The effect of MWCNTs on the evaporation rate was evaluated, showing that the MWCNTs with special water transport pathways were conductive to evaporation process. Overall, this work demonstrates a new direction for the future development of solar-driven evaporation.

Removal of Algae and Algal Toxins from a Drinking Water Source Using a Two-Stage Polymeric Ultrafiltration Membrane Process.

The release of algal toxins in algae-containing water sources poses a serious threat to drinking water safety and human health. The conventional water treatment processes of water plants have a limited ability to remove algae and algal toxins, especially algal toxins with a molecular weight (MW) of less than 1000 Da. To eliminate algal pollution from a water source, a two-stage ultrafiltration (UF) process with a large polysulfone hollow fiber membrane with a MW cut-off of 200 kDa and a small aromatic polyamide roll membrane with a MW cut-off of 1 kDa were applied after a traditional sand filter in a water treatment plant. UF operation conditions, including the operating time, pressure, and membrane flux, were investigated. With an operating pressure of 0.05-0.08 MPa, the polysulfone hollow fiber membrane removed algae effectively, as the influent algal cell concentration ranged from 1-30 cells/mL but exhibited a limited removal of algal toxins. With an operating pressure of 0.3-0.4 MPa, the elimination of microcystins (MCs) reached 96.3% with the aromatic polyamide roll membrane. The operating pressure, membrane flux, and operating time were selected as the experimental factors, and the effects on the UF efficiency to remove algal toxins and biodegradable dissolved organic carbon were investigated by the response surface methodology. The model showed that the order of influence on the membrane operating efficiency was operating pressure > membrane flux > running time. The optimal UF operating conditions were an operating pressure of 0.3 MPa, a membrane flux of 17.5 L/(m2·h), and a running time of 80 min.

Enhancing Water Treatment Performance of Porous Polysulfone Hollow Fiber Membranes through Atomic Layer Deposition.

Polysulfone (PSF) is one of the most used polymers for water treatment membranes, but its intrinsic hydrophobicity can be detrimental to the membranes' performances. By modifying a membrane's surface, it is possible to adapt its physicochemical properties and thus tune the membrane's hydrophilicity or porosity, which can achieve improved permeability and antifouling efficiency. Atomic layer deposition (ALD) stands as a distinctive technology offering exceedingly even and uniform layers of coatings, like oxides that cover the surfaces of objects with three-dimensional (3D) shapes, porous structures, and particles. In the context of this study, the focus was on titanium dioxide (TiO2), zinc oxide (ZnO), and alumina (Al2O3), which were deposited on polysulfone hollow fiber (HF) membranes via ALD using TiCl4, diethyl zinc (DEZ), and trimethylamine (TMA), respectively, and H2O as precursors. The morphology and mechanical properties of membranes were changed without damaging their performances. The deposition was confirmed mainly by energy-dispersive X-ray spectroscopy (EDX). All depositions offered great performances with a maintained permeability and BSA retention and a 20 to 40° lower water contact angle (WCA) than the raw PSF HF membrane. The deposition of TiO2 offered the best results, showing an enhancement of 50% for the water permeability and 20% for the fouling resistance of the PSF HF membranes.

Easily scaled-up and portable 3D polysulfone hollow fiber membrane tree for high-efficient solar-driven clean water production

Solar-driven water evaporation based on photothermal conversion materials, such as woods, sponges, and membranes, have been proved to be promising in the field of fresh water generation. It's urgent to develop portable, versatile, and efficient photothermal materials for affordable freshwater supply. Here, a hydrophilic polysulfone hollow fiber membrane (PSF HFM) with gradient porous structure and diameter of 50 μm was prepared through one-step phase inversion method. Inspired by nature, a highly efficient 3D solar-driven steam evaporator was fabricated via chemical vapor deposition polymerization (CVDP) of hydrophobic polypyrrole (PPy) on PSF HFMs. With rational 3D structure, capillary-driven water transportation property, optical absorption as high as 95%, heat localization, photothermal conversion, a solar-driven water evaporation rate of 2.6 kg m−2·h−1, and the conversion efficiency of 173.2% could be achieved. Furthermore, the HFM tree with affluent light-harvesting, efficient thermal management, and excellent stability showed a purified water collection efficiency of 14.18 L/(m2·day) in practical application, providing a latent way to boost water purification, regeneration, and desalination.

Microfluidic preparation of thin film composite hollow fiber membrane modules for water nanofiltration: Up-scaling, reproducibility and MOF based layers

BackgroundThe commercialization of thin film composite (TFC) hollow fiber (HF) membranes remains challenging owing to issues associated with membrane manufacturing. MethodsTFC membranes were synthesized by microfluidic interfacial polymerization of polyamide (PA) on polysulfone hollow fiber (HF) membrane modules. A total of 33 HF membrane modules were prepared with different number of HFs (from 1 to 25) and different lengths (from 10 to 50 cm). They were evaluated in a nanofiltration operation in terms of water permeance and rose Bengal (RB) and MgSO4 rejections. Significant findingsAmong the 33 modules, 73% showed RB rejections higher than 95%, while 36% of the modules reached rejections above 99%. During the membrane synthesis, different parameters, such as PA monomer concentration, residence time and reaction time, were studied. As a result, the amount of monomer was reduced by ca. 80%. The versatility of microfluidics allowed incorporating hydrophilic metal-organic framework (MOF) ZIF-93 to produce HF modules with PA/MOF bilayered membranes (a continuous layer of MOF between the support and the PA film) which led to an important enhancement of the water permeance from 1.3 (bare PA membrane) to 5.3 L·m−2·h−1·bar−1 (PA/ZIF-93 HF membrane), maintaining RB rejection above 95%.

The Simultaneously Removal of NOx and SO2 Processes through a Polysulfone Hollow Fiber Membrane Module

The Simultaneously Removal of NOx and SO2 Processes through a Polysulfone Hollow Fiber Membrane Module

Membrane Filtration Applied to the Purification of Sugarcane Bagasse Mild Alkaline Extracts

Sugarcane bagasse (SCB), a by-product of the sugar industry, is composed mainly of cellulose, hemicelluloses, and lignin, and can be used to replace petrochemical polymers in various applications. In this work, SCB was treated under mild alkaline conditions with 1.5% NaOH (m:v) and a solid:liquid ratio of 1:20 (m:v) at 60 °C, during 6 h. A 10 kDa polysulfone hollow fiber membrane was used for the purification of the extract in different filtration modes, namely concentration and diafiltration, and a combination of both modes. Permeate fluxes and rejection rates were evaluated at different transmembrane pressure (TMP) at the shear rate of 10,187 s–1, at 40 °C. In concentration mode, increasing the volume reduction factor up to 6.1 led to a significant increase in the retention rates of acid-soluble lignin (ASL) and xylan, and a decrease in inorganic salt content in the retentate. In diafiltration mode, after 2.9 diavolumes, the acid-insoluble lignin (AIL) and xylan rejection rates drastically increased, as did the rejection rates of ash.

Construction of inorganic-organic cascade enzymes biosensor based on gradient polysulfone hollow fiber membrane for glucose detection

The non-invasive diabetes sensing remains a widespread concern. Prussian blue nanoparticles (PBN) decorated with high superiority of enzymatic specificity, high catalytic activity, high stability, and low cost, can be operated in the field of enzyme-based sensing. Meanwhile, the glucose oxidase micro-particles (GOm) showed higher stability and reusability than the free glucose oxidase (GOx). Herein, a convenient PBN and GOm decorated hollow fiber membrane (PBN-GOm@HFM) colorimetric biosensor was developed through loading inorganic-organic cascade enzymes on the inner surface of polysulfone (PSF) HFM. Instead of complex testing methods and long incubation times, PB-GOm@HFM could be used for one-step glucose detection, and the linear range was found from 0.1 to 10 mM with a detection limit of 0.029 mM. The biosensor also showed excellent reusability and chemical stability (the initial activity decreased less than 10 % even after 20 cycles of detection glucose and the long-term activity stability remained over 80 % after storing for 4 weeks at 4 °C). Furthermore, the biosensor exhibited excellent semiquantitative non-invasive sensing testing for glucose in urine by the naked eye based on the siphon effect of HFM.

Inner‐coated highly selective thin film nanocomposite hollow fiber membranes for the mixture gas separation

AbstractPolyamide‐based thin film nanocomposite (TFN) membranes were prepared by incorporating nanoparticles in an aqueous phase containing m‐phenylenediamine (MPD) and an organic phase containing trimesoyl chloride (TMC) by interfacial polymerization (IP) method. The 3‐aminopropyltrimethoxy silane grafted mesoporous synthetic hectorite (APTMSH) was synthesized and added in an aqueous monomer solution while the IP. In this work, the TFN layer interfacial compatibility has been enhanced by building the covalent bond between APTMSH and other two monomers by IP method. The coating of the TFN selective layer was done on the inner surface of polysulfone hollow fiber membranes. The interesting results were obtained for the binary mixture gas separation containing water vapor/N2 and CO2/CH4. Improved gas permeance and selectivity have been obtained using APTMSH‐incorporated TFN membranes. The developed TFN membranes have been characterized using several physicochemical methods. The results show that with the addition of APTMSH in MPD solution up to 0.5 w/w% the best water vapor permeance 2485 GPU and CO2 permeance 22.3 GPU were obtained along with water vapor/N2 selectivity 725.5 and CO2/CH4 selectivity 26.68 respectively through APTMSH@TFN‐3 membrane.

Spinning of Polysulfone Hollow Fiber Membranes Using Constant Dope Solution Composition: Viscosity Control via Temperature.

The dope solution viscosity is an important parameter that largely determines the properties of hollow fiber membranes. In the literature available today, the change in viscosity is carried out only by changing the quantitative and/or qualitative dope solution compositions. However, such an important spinning parameter as temperature should significantly affect the dope solution viscosity. For the first time, the influence of the dope solution viscosity of a constant composition on polysulfone hollow fiber membrane properties was studied. The hollow fiber membranes were obtained by the phase separation method induced by a non-solvent (NIPS). The change in the dope solution temperature was carried out in the temperature range of 17-27 °C, providing a dope solution viscosity range of 34.3-21.6 Pa∙s. This work shows that even in such a narrow temperature range, the properties of polysulfone hollow fiber membranes change significantly. With a decrease in the viscosity in this temperature range, the wall thickness of the hollow fiber membrane decreases by 2.8 times; the permeance for the individual gases He and CO2 increases by 1.6-1.8 times, respectively; the ideal selectivity decreases by 1.12 times; the mean flow pore size increases by 1.63 times; and the surface porosity increases about 3 times.

Express method for detecting defects in polysulfone hollow fiber membranes with different porous structures

A new method of electroprometry has been proposed that allows continuous investigation of extended sections of a hollow fiber membrane. Samples of polysulfone hollow fiber membranes with different porous structures were obtained: finger-shaped and spongy. These membranes were examined on a laboratory electroprometric apparatus with continuous scanning along the length of the hollow fiber membrane sample at a high voltage of 15 kV. Defects were detected in these hollow fiber membranes by the proposed method of electroporometry, the nature of which was then investigated using scanning electron microscopy. A correlation was found between the size of the detected defect and the magnitude of the corona discharge current signal: the larger the defect, the greater the absolute value of the current. It is shown that the proposed method can be effectively used as an express method to study the homogeneity of the porous structure of hollow fiber membranes in extended areas with geometrical localization of possible defects.

Polysulfone hollow fiber membrane containing charcoal‑carbon nanomaterial for wastewater treatment in membrane bioreactor

In this research, charcoal‑carbon nanomaterial (charcoal-CNM) with sheet-like structure and high hydrophilicity was used to modify polysulfone (PSf)-based hollow fiber (HF) ultrafiltration (UF) membrane performance. Polyvinylpyrrolidone (PVP) was used as pore-former. Phase inversion method was employed for membrane preparation. The HF membranes were spun in three different CNM contents via dry/wet method. Field emission scanning electron microscopy (FESEM), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDX), tensile strength (TS), and water contact angle (WCA) analyses were used to characterize the fabricated membranes. Performance of the prepared HF membranes in a pre-conditioned bioreactor was also investigated. Compared to the neat membrane, increased porosity and mean pore size, reduced surface roughness and improved surface hydrophilicity were obtained for the nanocomposite membrane fabricated with 0.5 wt% of charcoal-CNM as the optimized membrane. The results demonstrated the positive effect of the charcoal-CNM with sheet-like structure and high hydrophilicity on the membrane surface properties and performance in the bioreactor. For the optimized membrane, chemical oxygen demand (COD) removal and protein rejection were achieved as 95.8 % and 94.3 %, respectively. Also, pure water flux (PWF) of the optimized membrane were achieved as 196.3 LMH.

Efficiencies of O-MBR and A/O-MBR for Organic Matter Removal from and Trihalomethane Formation Potential Reduction in Domestic Wastewater.

Lab-scale anoxic/oxic membrane bioreactor (A/O-MBR) and oxic membrane bioreactor (O-MBR) systems using a submerged polysulfone hollow-fiber membrane module with a pore size of 0.01 μm and a total surface area of 1.50 m2 were used to treat domestic wastewater. The sludge retention time (SRT) of each system was examined by setting the SRT to 10, 20, and infinity (no sludge withdrawal). The results showed that the total nitrogen removal efficiency of the A/O-MBR was more significant than that of the O-MBR at a SRT of infinity, with figures of 72.3% and 33.1% being found, respectively. The COD removal efficiencies of the A/O-MBR system with a SRT of 10 days, 20 days, and infinity were 82.4%, 84.3%, and 91.5%, respectively. The COD removal efficiencies of the O-MBR system with a SRT of 10 days, 20 days, and infinity were 79.3%, 81.5%, and 89.8%, respectively. An increase in the SRT resulted in an increase in the COD removal efficiency. The FEEM peak of the influent tended to decrease after an increase in the SRT for both systems (A/O-MBR and O-MBR). For the A/O-MBR system, the trihalomethane formation potential (THMFP) was significantly reduced by 88.91% (at a SRT of infinity). The THMFP declined significantly by 85.39% for the O-MBR system at a SRT of infinity. The A/O-MBR system showed a slightly higher efficiency than the O-MBR system in terms of the COD removal and the THMFP reduction. These results indicated that the MBR process, and the A/O-MBR system, in particular, could be used as an effective wastewater treatment process for many developing countries that are troubled by the emerging contamination of water and wastewater.

Highly Efficient Biogas Upgrading Process Using Polysulfone Hollow Fiber Membrane at Low Temperature

Highly Efficient Biogas Upgrading Process Using Polysulfone Hollow Fiber Membrane at Low Temperature

Modification of Polysulfone Hollow Fiber Membrane Inner Surface with Polydopamine Coating Treatment

Modification of Polysulfone Hollow Fiber Membrane Inner Surface with Polydopamine Coating Treatment

Comprehensive experimental and theoretical insights into the performance of polysulfone hollow-fiber membrane modules in biogas purification process

This study experimentally and theoretically explores the separation characteristics of polysulfone hollow fiber membranes for removing carbon dioxide and sulfur compounds from biogas and provides insights into the effects of various operating conditions on the separation characteristics of polysulfone membranes. The experiments to determine the effects of the stage cuts, feed pressure, and sulfur compounds on the membrane separation performance under dry conditions were performed using both binary gas (70% CH4, 30% CO2) and simulated biogas (30% CO2, 1900 ppm H2S, 100 ppm COS, and 100 ppm CS2, balance gas CH4). In addition, detailed theoretical investigations were conducted to understand the separation phenomena of the multicomponent gas through the hollow fiber membrane in conjunction with the experimental data for model validation; the model incorporated the mass transfer across the membrane and a concentration boundary layer adjacent to the membrane. The proposed model was in good agreement with the experimental results, which showed a relative error of < 5%, compared to the model that did not consider the concentration polarization and that based on the conventional mass transfer correlation. The removal efficiency of the sulfur compounds was 70–80% in the feed pressure range of 2.3–2.6 bar. Furthermore, the presence of sulfur compounds had a negligible effect on the separation performance of the polysulfone membrane.

Layered Antibiofouling Composite Membrane for Quenching Bacterial Signaling.

Bacterial quorum quenching (QQ) media with various structures (e.g., bead, cylinder, hollow cylinder, and sheet), which impart biofouling mitigation in membrane bioreactors (MBRs), have been reported. However, there has been a continuous demand for membranes with QQ capability. Thus, herein, we report a novel double-layered membrane comprising an outer layer containing a QQ bacterium (BH4 strain) on the polysulfone hollow fiber membrane. The double-layered composite membrane significantly inhibits biofilm formation (i.e., the biofilm density decreases by ~58%), biopolymer accumulation (e.g., polysaccharide), and signal molecule concentration (which decreases by ~38%) on the membrane surface. The transmembrane pressure buildup to 50 kPa of the BH4-embedded membrane (17.8 h ± 1.1) is delayed by more than thrice (p < 0.05) of the control with no BH4 in the membrane’s outer layer (5.5 h ± 0.8). This finding provides new insight into fabricating antibiofouling membranes with a self-regulating property against biofilm growth.