Polysulfone Hollow Fiber Membranes Research Articles

Novel PEP-PAN@PSF rods extraction of EDCs in environmental water, sediment, and fish homogenate followed by pre-column derivatization and UHPLC-MS/MS detection

In the study, novel polysulfone hollow fiber membrane (PSF) supported polar enhanced phase (PEP) particles-polyacrylonitrile (PAN) polymer thin-film rods (PEP-PAN@PSF rods) were developed for the extraction of five steroidal endocrine disrupting chemicals (EDCs) (estrone (E1), estradiol (E2), estriol (E3), ethinyloestradiol (EE2), 2-methoxyestradiol (2ME2)) and four phenolic EDCs (bisphenol A (BPA), hexestrol (HEX), diethylstilbestrol (DES), dienestrol (DE)) in environmental water, sediment, and fish muscle homogenates, followed by pre-column derivatization and ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The traditional preparation method for thin-film rods was improved by introducing a supporting membrane PSF between the external thin-film coating and the internal bare rod, avoiding the conventional pre-corrosion by strong acid/base. The commercial PEP prepared rods showed competitive capacity for both polar and nonpolar EDCs. In addition, pre-column derivatization with dansyl chloride (DNS-Cl) was adopted for the phenolic analytes prior to UHPLC-MS/MS detection, leading to a significant enhancement of sensitivity via analyzing the dansylated derivatives under positive electrospray ionization (ESI) mode instead of the analytes under negative ESI mode. The protocol was validated in four matrices including environmental water, sediment and two fish species. No matrix effects were observed in four matrices. The limits of detection (LODs) for the analytes were in the range of 0.002–0.072 μg L−1 for environmental water, 0.032–0.734 ng g−1 for sediment, and 0.011–0.435 ng g−1 for two fish species, respectively. Appropriate linearity was observed for all the analytes with correlation coefficients (R2) above 0.997. The intra-day trueness of the approach at low, medium and high levels was in the range of 86.6–116.1% with relative standard deviations (RSDs) lower than 15.4%. And the inter-day trueness was in the range of 84.6–114.8% with RSDs lower than 16.3%. The proposed method was successfully applied for the analysis of nine EDCs in environmental water, sediment, and fish muscle homogenates.

Effect of Temperature Exposition of Casting Solution on Properties of Polysulfone Hollow Fiber Membranes

It was shown for the first time that the conditions of thermal treatment of the casting solution significantly affect the morphology and transport properties of porous, flat, and hollow fiber polysulfone (PSf) membranes. It is ascertained that the main solution components that are subjected to thermo-oxidative destruction are the pore-forming agent polyethylene glycol (PEG) and solvent N-methyl-2-pyrrolidone (NMP). It is proved that hydroxyl groups of PEG actively react in the process of the casting solution thermo-oxidative destruction. It is shown that despite the chemical conversion taking place in the casting solution, their stability towards coagulation virtually does not change. The differences in the membrane morphology associated with the increase of thermal treatment time at 120 °C are not connected to the thermodynamic properties of the casting solutions, but with the kinetics of the phase separation. It is revealed that the change of morphology and transport properties of membranes is connected with the increase of the casting solution viscosity. The rise of solution viscosity resulted in the slowdown of the phase separation and formation of a more densely packed membrane structure with less pronounced macropores. It is determined experimentally that with the increase of casting solution thermal treatment time, the membrane selective layer thickness increases. This leads to the decrease of gas permeance and the rise of the He/CO2 selectivity for flat and hollow fiber membranes. In the case of hollow fibers, the fall of gas permeance is also connected with the appearance of the sponge-like layer at the outer surface of membranes. The increase of selectivity and decline of permeance indicates the reduction of selective layer pore size and its densification, which agrees well with the calculation results of the average membrane density. The results obtained are relevant to any polymeric casting solution containing NMP and/or PEG and treated at temperatures above 60 °C.

Optimization of pilot-scale 3-stage membrane process using asymmetric polysulfone hollow fiber membranes for production of high-purity CH4 and CO2 from crude biogas

In this work, we report on the design, construction and optimization of a pilot scale 3-stage membrane plant operated by a single compressor for production of high-purity CH4 and CO2 from crude biogas. In our previous works, we developed asymmetric polysulfone hollow fiber membranes with high CO2/CH4 separation properties and a numerical simulation program for a 3-stage membrane process for biogas separation. Herein, utilizing a pure gas permeation test, we report the effects of feed pressure and temperature on gas separation properties of the developed membrane modules. We also report the effects of various operating conditions on CH4 purity and recovery at the retentate, which were investigated using mixed gases as a function of stage-cut. Using a simulation program and the gas permeation data, we designed and constructed a 3-stage membrane plant that can treat 100 Nm3/h of crude biogas (65–75 vol% CH4, balanced CO2). It was confirmed that, in the constructed 3-stage pilot plant, the final purity and recovery ratios for CH4 and CO2 of the 3-stage membrane plant were significantly influenced by the operation conditions. Under optimized operation conditions, the 3-stage membrane plant exhibited outstanding biogas separation performance; high CH4 purity and good recovery (98.4% and 98.7%, respectively) were observed, together with high CO2 purity and recovery (97.2% and 97.0%, respectively). This study demonstrates the commercial applicability of the 3-stage membrane pilot plant using polysulfone hollow fiber membranes for simultaneous production of high purity CH4 and CO2 from crude biogas.

Single-use, single-pass tangential flow filtration using low-cost hollow fiber modules

Increasing pressures on biomanufacturing costs have led to renewed interest in the development of single-use technologies that can be readily adapted to continuous processing. The objective of this study was to use commercially available hollow fiber membranes, originally designed for high-flux hemodialysis, for single pass tangential flow filtration with high conversions. Experiments were performed with solutions of Immunoglobulin G (IgG) using polysulfone hollow fiber membrane cartridges with a surface area of 1.9 m2. The hollow fiber modules were able to provide more than 10-fold concentration of IgG in a single-pass with exit concentrations greater than 200 g/L. Stable operation was achieved during a continuous run for over a 120-h period with feed side pressure drops less than 1 kPa and transmembrane pressure drops less than 60 kPa. A single dialyzer was able to process 1.4 kg of IgG per day with a total cost of less than $0.004 per g of IgG. Flux-pressure profiles were in good qualitative agreement with a simple model accounting for concentration polarization effects and the variation of flux and pressure with axial position in the module. These results clearly demonstrate the potential of using these low-cost single-use hollow fiber modules for single-pass tangential flow filtration in continuous biomanufacturing.

Iron oxide nanoparticles improved biocompatibility and removal of middle molecule uremic toxin of polysulfone hollow fiber membranes

ABSTRACTMiddle molecule uremic toxins constitute to a quarter of uremic toxins present in human blood. In a condition where these uremic toxins accumulate in bloodstream due to renal failure, blood purification process using a high performance membrane is required. Here, we develop biocompatible mixed matrix membranes (MMMs) made up of polysulfone (PSf) and iron oxide nanoparticles (Fe2O3 NPs) with the focus to remove middle molecule uremic toxin effectively. The MMMs were evaluated in terms of their biocompatibility and separation performance. At higher Fe2O3 NPs loading, the MMM displayed a huge reduction of protein adsorption and platelet adhesion while maintaining normal blood coagulation time and acceptable complement activation. The optimized MMM exhibited high permeability (110.47 L m−2 h−1 bar−1), protein retention (99.9%) and demonstrated excellent clearance of urea (82%) and lysozyme (46.7%). The PSf/Fe2O3 MMM is proven to have promising attributes for hemodialysis application. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48234.

Effects of air gap on membrane substrate properties and membrane performance for biomass processing

We studied a correlation between the membrane substrate properties and the final performance of hollow fiber thin film composite (TFC) membrane for xylose/glucose concentration and acetic acid removal. Polysulfone (PSf) hollow fiber membrane substrate was fabricated using 20 wt% PSf, 2 wt% polyvinylpyrrolidone and 78 wt% dimethylformamide via dry-wet spinning process. The air gap distance was manipulated from 6 cm to 15 cm during spinning to produce different substrate membrane properties. The molecular weight cut-off (MWCO) and porosity of the membrane substrate increased as the air gap distance increased. Membrane substrate that was spun at 6 cm air gap showed a rapid phase inversion without much chain relaxation, thus producing the smallest MWCO (8 kDa) and an average pore diameter (4.46 nm). The TFC membrane produced using this membrane substrate showed the best performance in terms of solute rejection and separation factor. The rejection for xylose, glucose and acetic acid was 91.66±0.09%, 67.28±13.97%, and 13.08±3.00%, respectively. This results in an ideal separation factor of 3.20±1.27 for acetic acid/glucose and 10.42±0.25 for acetic acid/xylose.

Water vapor transport properties of interfacially polymerized thin film nanocomposite membranes modified with graphene oxide and GO-TiO2 nanofillers

Graphene oxide (GO) and its composite with TiO2 (GT) were utilized as nano-filler materials to prepare highly permeable and water vapor selective nanocomposite membranes. The nano-fillers were characterized using different analytical tools to determine their physicochemical properties. Nanocomposite membranes were prepared by dispersing the nano-fillers in aqueous phase monomer solution for interfacial polymerization reaction on the inner surface of Polysulfone hollow fiber membrane. Surface morphology and bonding chemistry of the nanocomposite membrane was analyzed using various analytical tools. The two types of nano-fillers were compared for their compatibility with the polyamide matrix, and consequently, the water vapor separation performance of the resulting membrane. Results revealed that both the nano-fillers are firmly attached to the polyamide layer via hydrogen and covalent bonds. GT based membranes have higher surface roughness and better hydrophilicity as compared to GO. In addition, GT membranes have more carboxyl groups and lesser degree of cross-linking due to the interference with interfacial polymerization reaction. This leads to a higher permeance (2820 GPU) and a water vapor/nitrogen selectivity when compared to other TFN membranes reported in literature. The nano-fillers act as active sites for preferential transport of water vapor molecules through the membrane thereby, significantly improving water vapor permeance.

Elaboration of High Permeable Macrovoid Free Polysulfone Hollow Fiber Membranes for Air Separation

In this work, polysulfone hollow fibers with oxygen permeance 70 L (STP)/(m2·h·bar) and selectivity α(O2/N2) = 6 were obtained. A decrease in the dope solution temperature allowed to diminish macrovoids due to the increase of the dope viscosity from 15.5 Pa·s at 62 °C to 35 Pa·s at 25 °C. To reduce the fiber diameter, thereby increasing the packing density, they were spun at high linear velocities. A hollow fiber membrane element was produced with effective membrane area 2.75 m2 and packing density 53%. Its air separation performance was evaluated to bridge laboratory studies and practical application.

Air gap membrane distillation of MEG solution using PDMS coated polysulfone hollow fiber membrane

Surface modified porous polysulfone (PSF) hollow fiber membrane was prepared by dip-coating of polydimethylsiloxane (PDMS). The prepared membranes were used in an air gap membrane distillation (AGMD) process for dehydration of MEG-water mixtures. The membranes were characterized in terms of Field Emission Scanning Electronic Microscopy (FESEM), N2 permeation, contact angle measurement and wetting pressure. From FESEM images, the prepared membrane showed a porous structure with finger-like cavities. In addition, formation of ultra-thin coating layer on the inner and outer surface was confirmed by FESEM. From N2 permeation test, the modified membrane showed smaller mean pore size (9 nm) and lower surface porosity compared to the plain membrane. The modified membrane showed a good hydrophobicity with water contact angle of 118° and wetting pressure of 800 kPa. The permeate flux of about 26 kg/m2h was obtained for the modified membrane at MEG concentration of 20 wt%, feed temperature of 90 °C and feed velocity of 0.66 m/s. Due to the improved structure, the modified membrane showed a stable AGMD operation for 80 h compared to the plain membrane.

Polydopamine Nanoparticle-Coated Polysulfone Porous Granules as Adsorbents for Water Remediation.

Water purification technologies possibly based on eco-sustainable, low cost, and multifunctional materials are being intensively pursued to resolve the current water scarcity and pollution. In this scenario, polysulfone hollow porous granules (PS-HPGs) prepared from scraps of the industrial production of polysulfone hollow fiber membranes were recently introduced as adsorbents and filtration materials for water and air treatment. Here, we report the functionalization of PS-HPGs with polydopamine (PD) nanoparticles for the preparation of a new versatile and efficient adsorbent material, namely, PSPD-HPGs. The in situ growth of PD under mild alkaline oxidative polymerization allowed us to stably graft PD on polysulfone granules. Enhanced removal efficiency of ofloxacin, an antibiotic drug, with an improvement up to 70% with respect to the pristine PS-HPGs, and removal of Zn(II) and Ni(II) were also observed after PD modification. Remarkably, removal of Cu(II) ions with an efficiency up to 80% was observed for PSPD-HPGs, whereas no adsorption was found for the PD-free precursor. Collectively, these data show that modification with a biocompatible polymer such as PD provides a simple and valuable tool to enlarge the field of application of polysulfone hollow granules for water remediation from both organic and metal cation contaminants.

Efficiently improved oil/water separation using high flux and superior antifouling polysulfone hollow fiber membranes modified with functionalized carbon nanotubes/graphene oxide nanohybrid

Oil/water separation using membrane technology has gained a tremendous attention in the recent years. In the present study, a nanohybrid consisting of carboxylated carbon nanotubes and graphene oxide nanosheets (CNTs/GO) was embedded in polysulfone hollow fiber membranes (P HFMs) with an aim to improve their physicochemical properties, mainly surface functionality, hydrophilicity, mechanical strength and surface charge, and separation performance including antifouling property, water permeation flux and oil/water separation. It was found that the blending of nanohybrid in HFMs showed the positive effect on the properties of HFMs with high hydrophilic nature (water contact angle of ∼51.4°), high mechanical strength (Young’s modulus of 510.2 ± 12.4 MPa) and high negative surface charge (zeta potential of – 35.9 ± 2.5 mV). Notably, high pure water permeability (487.9 ± 25.4 mL/m2/h/mmHg), superior antifouling property with 90.5% flux recovery, and significantly high oil/water separation (98.7 ± 1.2%) were measured for Psf composite HFMs with 1 wt.% CNTs/GO nanohybrid. Thus, this study, through the above-obtained experimental results, demonstrated the potential efficacy of the polysulfone-CNTs/GO composite HFMs for efficient oil/water separation.

Photocatalytic Polysulfone Hollow Fiber Membrane with Self-Cleaning and Antifouling Property for Water Treatment

Membrane fouling is a critical issue during the membrane filtration process. Photocatalytic membranes have been developed to address the membrane fouling issue, although current approaches are mostly based on irradiation under the UV light. In this study, we report the preparation of a photocatalytic membrane with self-cleaning property under visible light irradiation. A 3-(3,4-dihydroxyphenyl)lalanine (LDOPA) layer was first attached onto the surface of polysulfone (PSF) hollow fiber membrane (HFM) via self-polymerization with an immersion time of 6 h/12 h/18 h/24 h. Then, N–TiO2–NH2 (NTN) was introduced to the LDOPA layer via chemical bonding. The NTiO2 NPs were able to degrade humic acid (HA) under visible light irradiation. Various methods were applied to characterize the photocatalyst and membrane, including thermal gravimetric analysis, scanning electron microscopy, and cyclic filtration tests of deionized water and HA solution. The normalized water flux of PSF 18LDOPA-NTN HFM was 22% higher than th...

Preparation and characterization of polysulfone membrane coated with poly(ether block amid) for oxygen enrichment process

Oxygen enriched air (OEA) is widely applied in various areas such as chemical and medical applications. Currently, cryogenic distillation and pressure swing adsorption are the two common technologies that being commercially used for i the production of OEA. However, these two techniques are not economically favorable due to required intensive energy and large built-up area. With the advancement of membrane technology in separation process, it garners the interest from both industrial and academic to explore the feasibility of membrane in gas separation. In this study, polysulfone (PSF) hollow fiber membranes with poly(ether block amide) (PEBAX) coating were used for the separation of O2/N2 gas. The hollow fiber membranes used in this work were fabricated by phase inversion spinning process using PSF pellet, along with N,N-dimetyhlacetamide (DMAc) and ethanol (EtOH) as solvent and co-solvent, whereas tetrahydrofuran (THF) as additive. The fabricated membrane exhibited dense structure in the inner layer whereas finger like layer at the outer surface. The formation of this structure was attributed by rapid phase inversion of the solution arose from strong solvent used. The EDX surface mapping analysis confirmed the formation of PEBAX coating on the membrane surface. Gas permeation study in this work illustrated that the pristine PSF membrane exhibited better gas separation performance relative to the PEBAX coated membrane with 20% higher in terms of permeance. The results obtained from this work suggested that the PEBAX coating enhanced the membrane surface but not certain to improve the gas separation performance. Further study on the PEBAX materials for the membrane coating is essential to polish its potential in gas separation.

Separation of sugarcane bagasse mild alkaline extract components by ultrafiltration – Membrane screening and effect of filtration parameters

Mild alkaline treatment (1.5% NaOH (w/v), solid:liquid ratio of 1:20, 60 °C, 6 h) of sugarcane bagasse (SCB) produced an extract composed of hemicelluloses, lignin, phenolic monomers and acetic acid. The purification of this extract, usually considered a by-product in lignocellulosic biorefineries, is of major importance to give value to the whole mild alkaline fractionation process. Ultrafiltration was assessed to separate the components of the SCB alkaline extract which is a prerequisite for their further valorization. The permeate flux and the retention of the extract components were studied on seven membranes (polysulfone hollow fiber and ceramic tubular) with different molecular weight cut-offs, under various operating conditions. On all the membranes tested, oligomers of lignin and hemicelluloses were separated from salts, phenolic monomers and acetic acid. The 10 kDa polysulfone hollow fiber membrane presented the highest lignin and hemicelluloses retention, exceeding 85 and 90%, respectively, regardless of shear rate and with a limited influence of transmembrane pressure. For salts, acetic acid and phenolic monomers, retention levels of about 0–10% were recorded for this membrane. At 2.8 bar and at 20 °C, the permeate flux reached 16 L/h/m2 and the critical flux was not reached.

Surface Modified Polysulfone Hollow Fiber Membranes for Ethane/Ethylene Separation Using Gas-Liquid Membrane Contactors with Ionic Liquid-Based Absorbent

Olefin/paraffin separation is an important technological process. A promising alternative to conventional energy-consuming methods is employment of gas-liquid membrane contactors. In the present work, the membranes used were polysulfone (PSf) asymmetrical porous hollow fibers fabricated via the NIPS (non-solvent induced phase separation) technique in the free spinning mode. The surface of the fine-pored selective layer from the lumen side of the fibers was modified by layer-by-layer deposition of perfluorinated acrylic copolymer Protect Guard® in order to hydrophobized the surface and to avoid penetration of the liquid absorbent in the porous structure of the membranes. The absorbents studied were silver salts (AgNO3 and AgBF4) solutions in five ionic liquids (ILs) based on imidazolium and phosphonium cations. The membranes were analyzed through gas permeance measurement, SEM and dispersive X-ray (EDXS). Contact angle values of both unmodified and modified membranes were determined for water, ethylene glycol, ILs and silver salts solutions in ILs. It was shown that the preferable properties for employment in membrane contactor refer to the PSf hollow fiber membranes modified by two layers of Protect Guard®, and to the absorbent based on 1 M AgNO3 solution in 1-ethyl-3-methylimidazolium dicyanamide. Using the membrane contactor designed, ethylene/ethane mixture (80/20) separation was carried out. The fluxes of both components as well as their overall mass transport coefficients (MTC) were calculated. It was shown that the membrane absorption system developed provides absorption of approx. 37% of the initial ethylene volume in the mixture. The overall MTC value for ethylene was 4.7 GPU (gas permeance unit).

Research and Development of Polysulfone Hollow Fiber Membrane for Controlled Protein Adsorption

Research and Development of Polysulfone Hollow Fiber Membrane for Controlled Protein Adsorption

Intensification of CO2 separation performance via cryogenic and membrane hybrid process — Comparison of polyimide and polysulfone hollow fiber membrane

Cryogenic-membrane hybrid CO2 capture process has been considered as a promising alternative for the standalone processes to mitigate the critical challenge of energy penalty. In this work, two different commercial hollow fiber membranes were tested at low temperature condition to find the possibility of consisting a novel cold-membrane-cryogenic hybrid process. The gas permeation properties of membranes were evaluated at different operating temperature, CO2 concentration and stage cut. The experimental results indicated that cryogenic condition could facilitate to improve the CO2/N2 selectivity with a minimum permeance reduction. Specifically, with the operating temperature dropped to −20 °C and feed pressure set at 0.7 MPa, the CO2 selectivity of polyimide membrane increased by 166% with the permeance declined by 31%. Meanwhile, the CO2 recovery and purity of polyimide membrane achieved 92% and 49% at the temperature of −20 °C and pressure 0.7 MPa, respectively. It can be observed that operating membrane at cold condition could be a promising approach to intensify the CO2 separation, and thus decrease the energy consumption of subsequent CO2 liquefaction or desublimation in the hybrid process.

Study on the effect of spinning conditions on the performance of PSf/PVP ultrafiltration hollow fiber membrane

Asymmetric, porous ultrafiltration polysulfone (PSf) hollow fiber membranes were fabricated via the dry-wet phase inversion spinning technique specifically for haemodialysis membrane. The objective was to discover the suitable spinning condition for the fabrication of ultrafiltration hollow fiber membrane with desired sponge-like structure. During haemodialysis procedure, uremic toxins such as urea and creatinine range from size 10,000-55,000 Da needs to be excreted out from the blood. While, proteins such as albumin (66,000 Da) need to be retained. The physical structure or morphology of a fabricated membrane is a major concern in determining the efficiency of a dialysis membrane. Different type of membrane morphology will give a different result in term of its permeability and clearance efficiency. The phase inversion spinning technique is suitable in producing ultrafiltation (UF) membrane where the average pore size of the fabricated membrane is in the range of 0.001 – 0.1 µm. However, there is many factors need to be controlled and manipulated in the phase inversion technique. In this study, the effect of the PVP on membrane pore size and performances were analysed. The contact angle measurement was measured to determine the hydrophilicity of the fibers. The hydrophilic polymer is favorable to avoid fouling and increase its biocompatibility. Furthermore, the diameter of the hollow fibers was determined using a scanning electron microscope (SEM). The effects of different morphology of the hollow fibers on the performance of the membranes were evaluated by pure water flux and BSA rejection. Both techniques were tested using permeation flux system. Based on the results obtained, it is found that the finger-like macrovoids in PSf hollow fiber membranes were suppressed by adding 8% PVP (Mw of 360 kDa) into the spinning dope solution as the result of a drastic increase in dope viscosity. On top of that, fiber spun with 8% PVP show more porous structure which contribute to higher permeability of the membrane. The result of this study can benefit to the membrane field of research especially in membrane technology for haemodialysis application.

Influence of ultrasound on the clearance of toxic substances from Polysulfone hollow fiber membrane used in a dialyzer filter

Abstract The aim of this work was to investigate the potential of high frequency ultrasound for the cleaning of a Polysulfone (PSU) ultrafiltration membrane used in hemodialysis. The blood substitute solution flowing through the hollow fiber membrane used in the High Flux F60 dialyzers has been sonicated by ultrasonic (US) waves with 1 MHz frequency and 2 W/cm2 in situ intensity. The solution was comprised of toxic compounds such as Urea, Creatinine, Vitamin B12 and Inulin. The effect of US was represented by comparison of the clearance in both OFF and ON ultrasound conditions. The results of these studies have been demonstrated that US can enhance the permeability of the PSU dialyzer membrane. Results revealed that US had significant effect (p-value ˂ 0.05) on the clearance of Inulin as a large molecule (5200 D) and accelerated its filtration by 28%. The proposed dialysis method can be used alongside the existing dialysis machine.

Fabrication of composite hollow fiber membranes with thin film selective layers from highly permeable polymers

Fabrication of highly efficient composite gas separation membranes involves selection and pretreatment of the support material. In the present work, porous support pretreatment was for the first time studied for deposition of thin selective layers made from highly permeable organosilicon polymers. Asymmetric polysulfone hollow fiber membranes with mesoporous skin layer structure were employed as supports. It was shown that preliminary impregnation of the support pores is essential for composite membranes fabrication. If poly[1-(trimethylsilyl)-1-propyne] layers from casting solution are deposited onto the polysulfone support without impregnation, the casting solution penetrates the mesoporous layer to a depth of > 1 μm, thus predominantly (> 90%) contributing the overall mass transfer resistance, as estimated by the resistance-in-series model. Such membranes provide relatively poor transport properties: carbon dioxide permeance is 0.2-0.3 m3/(m2·h·bar). Preliminary impregnation of porous support by distilled water or aqueous glycerol solution prevents casting solution penetration into porous support and results in defect-free thin polymer layer. According to SEM, the deposited selective layer thickness is less than 1 μm. Composite membranes fabricated via this technique provide permeance increase more than order of magnitude. The composite membranes with poly[1-(trimethylsilyl)-1-propyne] and polydimethylsiloxane selective layers show high transport properties in gas-liquid membrane contactors.