Ceramic Composite Membrane Research Articles

Highly efficient decomplexation of chelated nickel and copper effluent through CuO–CeO2–Co3O4 nanocatalyst loaded on ceramic membrane

A novel CuO–CeO2–Co3O4 nanocatalyst loaded on Al2O3 ceramic composite membrane (CCM-S) was synthesized through spraying-calcination method, which can be beneficial to the engineering application of scattered granular catalyst. BET and FESEM-EDX testing revealed that CCM-S possessed a porous character with high BET surface area of 22.4 m2/g and flat modified surface with extremely fine particle aggregation. The CCM-S calcined above 500 °C presented excellent anti-dissolution effect due to the formation of crystals. XPS indicated that the composite nanocatalyst possessed the variable valence states, which were conducive to exert the catalytic effect of Fenton-like reaction. Subsequently, the effects of experimental parameters including fabricate method, calcination temperature, H2O2 dosage, initial pH value, and CCM-S amount were further investigated considering the removal efficiency of Ni(II)-complex and COD after decomplexation and precipitation (pH = 10.5) treatment within 90 min. Under the optimal reaction condition, the residual Ni(II)-complex and Cu(II)-complex concentration from actual wastewater was all lower than 0.18 mg/L and 0.27 mg/L, respectively; meanwhile, the removal efficiency of COD was all higher than 50% in the mixed electroless plating effluent. Besides, the CCM-S could still maintain high catalytic activity after a six-cycle test, and the removal efficiency was slightly declined from 99.82% to 88.11%. These outcomes indicated that CCM-S/H2O2 system was provided with a potential applicability on treatment of real chelated metal wastewater.

A Brief Overview of the Microstructural Engineering of Inorganic-Organic Composite Membranes Derived from Organic Chelating Ligands.

This review presents a concise conceptual overview of membranes derived from organic chelating ligands as studied in several works. The authors' approach is from the viewpoint of the classification of membranes by matrix composition. The first part presents composite matrix membranes as a key class of membranes and makes a case for the importance of organic chelating ligands in the formation of inorganic-organic composites. Organic chelating ligands, categorized into network-modifying and network-forming types, are explored in detail in the second part. Four key structural elements, of which organic chelating ligands (as organic modifiers) are one and which also include siloxane networks, transition-metal oxide networks and the polymerization/crosslinking of organic modifiers, form the building blocks of organic chelating ligand-derived inorganic-organic composites. Three and four parts explore microstructural engineering in membranes derived from network-modifying and network-forming ligands, respectively. The final part reviews robust carbon-ceramic composite membranes as important derivatives of inorganic-organic hybrid polymers for selective gas separation under hydrothermal conditions when the proper organic chelating ligand and crosslinking conditions are chosen. This review can serve as inspiration for taking advantage of the wide range of possibilities presented by organic chelating ligands.

Waste heat recovery enhancement in the CO2 chemical absorption process by hydrophobic-hydrophilic composite ceramic membranes

A novel ceramic composite membrane configuration was proposed to improve the waste heat recovery performance from stripped gas in the CO2 chemical absorption process. Tubular hydrophobic and hydrophilic ceramic membranes were serially assembled to form a single composite membrane. The stripped gas and bypassed CO2-rich solvent flowed countercurrent on both sides of the composite membrane. The waste heat recovery performance from the stripped gas was investigated under eight membrane configurations using: hydrophobic, hydrophilic, and Janus membranes (i.e., with hydrophilic inner-surface and hydrophobic outer-surface, and viceversa). Results showed that when the stripped gas enters the hydrophobic segment, the waste heat recovery performance increases to a plateau and then decreases with an increasing length of the hydrophobic segment. When the length ratio of the hydrophobic segment was 25%, a maximum waste heat recovery performance was achieved. Similarly, an increase in the hydrophobicity of the hydrophobic segment caused an increase in waste heat recovery performance, in which the optimal water contact angle (CA) was 137.35°. As a result of the abovementioned conditions, a 7.44%–25.15% higher waste heat recovery of the composite membrane was achieved compared to commercial hydrophilic membranes.

A TiO2 modified whisker mullite hollow fiber ceramic membrane for high-efficiency oil/water emulsions separation

Design and preparation of membranes with ultrahigh separation performance and antifouling property for oil-in-water (O/W) emulsions remains challenging. In this study, a high flux mullite/TiO2 ceramic composite membrane was prepared via multi-precipitation of TiO2 on a whisker mullite hollow fiber support synthesized by combining phase inversion and high-temperature sintering techniques. The results showed that the generated whisker mullite structure improved the permeation flux, and the micro-nano structured TiO2 functional layer endowed the membrane surface with superhydrophility and stability. The retention of the optimal composite membrane (M20T13) that was soaked in the titanium solution 20 times for 13 min each time for the O/W emulsions like n-hexane, toluene and engine oil maintained over 98 %, and the flux after 6 h filtration was 668.34 L·m−2·h−1, 487.25 L·m−2·h−1 and 258.66 L·m−2·h−1, respectively, much higher than that of the optimal substrate (F3A1, mass ratio of fly ash: Al2O3 = 3:1). Moreover, the flux recovery rate of M20T13 was much higher than that of F3A1 after chemical backwashing. This work manifests great potential in O/W treatment fields.

Dual-Phasic, Well-Aligned, and Strong Flexible Hydrophobic Ceramic Membranes for Efficient Thermal Insulation in Extreme Conditions.

The inherent brittleness and hydrophilicity of ceramics pose a great challenge to designing a reliable structure that can resist mechanical loads and moisture in extreme conditions with high temperature and high humidity. Here, we report a two-phase hydrophobic silica-zirconia composite ceramic nanofiber membrane (H-ZSNFM) with exceptional mechanical robustness and high-temperature hydrophobic resistance. For the dual-phasic nanofibers, the amorphous silica blocked the connection of zirconia nanocrystals, and the lattice distortion was observed due to Si in the ZrO2 lattice. H-ZSNFM has strong strength (5-8.4 MPa), high hydrophobic temperature resistance (450 °C), high porosity (89%), low density (40 mg/cm3), low thermal conductivity (30 mW/m·K), and excellent thermal radiation reflectivity (90%). By simulating the actual high-temperature and high-humidity environment, 10-mm-thick H-ZSNFMs can reduce the heat source from 1365 to 380 °C and maintain complete hydrophobicity even in a water vapor environment of 350 °C. This means that it has superior insulation and waterproof performance even in a high-temperature water environment. For firefighting clothing, H-ZSNFM displayed waterproof and insulation layers, which have excellent thermal protection performance and achieve incompatibility between water and fire, providing valuable time for fire rescue and a safety line of defense for emergency personnel. This design strategy with mechanical robust and hydrophobic temperature resistance applies to the development of many other types of high-performance thermal insulation materials and presents a competitive material system for thermal protection in extreme conditions.

Design and Validation of an Experimental Setup for Evaluation of Gas Permeation in Ceramic Membranes

An experimental setup for the evaluation of permeation of gaseous species with the possibility of simultaneously collecting electrochemical impedance spectroscopy data in disk-shaped ceramic membranes was designed and assembled. It consists of an alumina sample holder with thermocouple tips and platinum electrodes located close to both sides of the sample. Water-cooled inlet and outlet gas connections allowed for the insertion of the sample chamber into a programmable split tubular furnace. Gas permeation through a ceramic membrane can be monitored with mass flow controllers, a mass spectrometer, and an electrochemical impedance analyzer. For testing and data validation, ceramic composite membranes were prepared with the infiltration of molten eutectic compositions of alkali salts (lithium, sodium, and potassium carbonates) into porous gadolinia-doped ceria. Values of the alkali salt melting points and the permeation rates of carbon dioxide, in agreement with reported data, were successfully collected.

The efficient treatment of pickling wastewater using a self-assembled in situ polymerized ceramic membrane with graphene/carbon nanotubes/polypyrrole

Electric flocculation coupled with rGO–CNT–PPy modified composite conductive ceramic membrane reaction device can efficiently remove metal ions and organic matter from pickling wastewater. It also improves the pH value of pickling wastewater.

Peroxymonosulfate activated by composite ceramic membrane for the removal of pharmaceuticals and personal care products (PPCPs) mixture: Insights of catalytic and noncatalytic oxidation

A composite manganese-based catalytic ceramic membrane (Mn-CCM) was developed by a solid-state sintering method, and its effectiveness toward activation of peroxymonosulfate (PMS) for the degradation of 11 pharmaceutical and personal care products (PPCPs) mixture was tested. The optimized Mn-CCMs/PMS system showed remarkable degradation efficiencies for PPCPs mixture with total removal >90% in ultrapure water, river water and natural organic matter (NOM) solution. The Mn-CCMs/PMS system showed the contribution of different phenomena in PPCPs removal in the order of catalytic oxidation (54.7%, Mn-CCMs/PMS) > noncatalytic oxidation (42.3%, PMS oxidation) > adsorption (3.0%, by Mn-CCMs). The singlet oxygen (1O2) was the dominant reactive oxygen specie for the degradation of PPCPs in all water matrices proved by the quenching experiments and electro-paramagnetic resonance (EPR) spectroscopy. The extraordinary stability of Mn-CCMs for the activation of PMS has been noted in terms of repeatability experiments for PPCPs degradation with fewer leaching of Mn (1.9 to 3.6 µg/L). Mineralization was achieved in the range of 28–65% for different water matrices. The toxicity of the PPCPs mixture was reduced by 85.9%. The Mn-CCMs/PMS system showed a reduction (25–100%) in precursors of different carbon- and nitrogen-based disinfection by-products. This study found the Mn-CCMs/PMS system as a feasible purification unit for removing trace concentrations of PPCPs (ng/L) in real drinking water matrices.

One-step sintering for anti-fouling piezoelectric α-quartz and thin layer of alumina membrane

Lead-free piezoelectric ceramics are attracting significant attention in the construction of separation membranes because they offer a self-cleaning function and have no risk of lead leaching from the materials. In this study, the fabrication of cost-sensitive and self-cleaning ceramic composite membranes via co-sintering of a porous α-quartz green support and an alumina microfiltration layer is reported. The α-quartz green support prepared by aqueous gel-casting has benign wettability and flexural strength, which is beneficial for forming a thinner and homogeneous membrane layer by dip-coating. The effects of the co-sintering temperature and dip-coating parameters on the pore size, permeance, mechanical and chemical stabilities, and piezoelectric properties were further investigated. The optimal membrane had an average pore size of 190 nm by co-sintering at 1200 °C and a strongest ultrasound response of 15 mV at an alternating voltage (AV) of 100 V. Finite element analysis showed that the composite membrane generated a beneficial displacement and acoustic pressure (acpr) for cavitation effect. In-situ mitigation of fouling was demonstrated during 500 ppm oil-in-water (O/W) emulsion filtration, which resulted in a stationary flux (Jstat) of 190 L m−2 h−1·bar−1, increased by 65.7% at 100 V AV.

Pre-Treatment and Turbidity Reduction of Sea Waters Using New Composite Ceramic Microfiltration Membranes with Iron Oxide Additive

In this research, an experimental study was carried out on the pre-treatment and turbidity removal of Persian Gulf water using cross flow microfiltration by new composite ceramic membranes. Three types of tubular microfiltration composite ceramic membranes that consisted of Mullite, Mullite/SiC, and Mullite/SiC/Fe2O3 with different compositions were fabricated at relatively low temperature (1250 °C) with extrusion and sintering for this purpose. Furthermore, changes in porosity, pore size, and mechanical strength were compared in Mullite membranes and composite membranes to find the most suitable membrane for turbidity removal from seawater. According to the results, the most suitable synthetic membrane was M/SiC/Fe10 membrane with 60:30:10 ratios of mullite, silicon carbide, and iron oxide with 64.6 ± 2% porosity, average pore size of 0.54 μm, 95.4% turbidity removal, pure water permeability of 3811 L/m2.h, and higher mechanical strength (22.4 MPa) compared to other fabricated membranes. Results of Hermia’s models for fouling modeling indicated that the dominant mechanism of blocking in all membranes was standard pore blocking with the best compliance with experimental data. Therefore, results demonstrated that the addition of Fe2O3 to silicon carbide ceramic microfiltration membranes, with a specific weight percentage, improves their mechanical properties and membrane performance for pre-treatment of seawaters.

A high-stable polyacrylonitrile/ceramic composite membranes for high-voltage lithium-ion batteries

Polymer/ceramic composite gel electrolytes are considered promising alternatives to conventional liquid electrolytes for developing high-energy and safer lithium-ion batteries (LIBs). In this study, we prepare three polyacrylonitrile (PAN)/ceramic composite membranes with 40 wt% Al2O3, BaTiO3, and TiO2 ceramic nanoparticles and compared their properties with those of pristine PAN. Structural and morphological investigations confirm the formation of the polymer/ceramic composites. The interconnected microporous structure PAN/ceramic composites efficiently entrapped a large amount of liquid electrolyte and exhibit improved ionic conductivity compared to that of the pristine PAN electrolyte. The PAN/Al2O3 composite electrolyte displays the highest ionic conductivity of 5.2 × 10−3 S cm−1 under ambient conditions with low Li+-coordinated EC and high free PF6− concentration. Thermal shrinkage tests indicate that the addition of ceramic particles enhance the thermal stability of the PAN/ceramic membranes, as compared to that of commercial polyethylene separators. The PAN/ceramic composite electrolytes are tested as separator-cum-electrolytes in lithium-ion batteries using a LiNi0.8Co0.1Mn0.1O2 (NCM811) high-voltage cathode, and a lithium metal anode. The LIB with the PAN/Al2O3 composite electrolyte delivers a high capacity of 184 mAh g−1 at 0.5 C, which is retained at 85% after 100 cycles, demonstrating the best rate performance among all tested composite electrolytes.

Oxygen permeability and surface kinetics of composite oxygen transport membranes based on stabilized δ-Bi2O3

Composite ceramic membranes based on the ionic conducting Tm-stabilized δ-Bi2O3 (BTM) and the electronic conducting (La0.8Sr0.2)0.99MnO3-δ (LSM) exhibit among the highest oxygen flux values reported for Bi2O3-based membranes. Here, we use pulse-response isotope exchange (PIE) and oxygen flux measurements to elaborate on limiting factors for the oxygen permeation in BTM - 40-70 vol% LSM composites. Once both phases percolate, between 30 and 50 vol% BTM, the flux is essentially independent of the BTM/LSM volume ratio. The oxygen permeability is under mixed diffusion- and surface control, gradually becoming more bulk-limited with increasing temperature. The oxygen exchange coefficients of BTM-LSM are significantly higher than its constituent phases, revealing that a cooperative surface exchange mechanism enhances the kinetics. Some of the Tm was substituted with Pr to introduce electronic conductivity in BTM. (Bi0.8Tm0.15Pr0.05)2O3-δ (BTP) exhibits higher surface exchange coefficients compared to BTM, but the oxygen flux remains one order of magnitude lower than that of percolating BTM-LSM composites.

Surfactant induced ultrafiltration of heavy metal ions from aqueous solutions using a hybrid polymer–ceramic composite membrane

A low-cost ceramic membrane was coated with cellulose acetate (CA) using different polymer concentrations and dipping durations. The porosity of the membrane decreased considerably (from 58.4 % to 12.1 %) with an increase in polymer concentration from 2.5 to 10 wt. %. The values of the porosity increased and layer thickness decreased slightly with a decrease in dipping time (from 60 s to 15 s). The membrane prepared using 5 wt. % CA in acetone and 45 s dipping duration (T-3) had a polymer separation layer of thickness 14.2 µm and was found to be optimal with 51.8 % porosity, 35 nm pore diameter and a liquid (water) permeability of 7.39 × 10–10 m3/m2·s·Pa. This membrane was applied for micellar enhanced ultrafiltration of three heavy metal ions, namely, Cu(II), Cr(VI) and Ni(II). The prepared membrane (T-3) was highly effective in ultrafiltration applications as evidenced from complete rejection (≈ 100 %) of cetylpyridinium chloride (CPC) along with satisfactory removal (>99.7 %) of metal ions.

Constructing (reduced) graphene oxide enhanced polypyrrole /ceramic composite membranes for water remediation

Electrically conductive membrane, acting as an electrode while separating, has already been demonstrated breakthrough performance in mitigating membrane fouling and improving contaminant removal. However, only a few works have reported about conductive ceramic membranes because of their poor conductivity. Herein, we developed a kind of highly conductive polypyrrole (PPy) coated ceramic membrane (CM) with excellent anti-fouling performance through incorporating graphene oxide (GO)/reduced graphene oxide (rGO). During the process, π-π interactions, hydrogen bond or electrostatic attractions occur between GO/rGO and pyrrole (Py), leading to the adsorption of Py onto the GO/rGO rather than polymerizing directly on membrane surface, which effectively improve the membrane properties such as flux, porosity, hydrophilicity, Zeta potential, and roughness, etc. Particularly, due to the formation of a complete conductive network between PPy and CM with GO/rGO, as well as high conductivity of rGO, the electrical resistivity of PPy membrane was decreased from 8.46 to 3.56 and 0.87 kΩ/cm, respectively. Interestingly, the average specific flux of rGO/PPy (GO/PPy) membrane under electric field was 47.5% (33.6%) higher than that of CM support during yeast filtration, showing strong promise in water remediation. In particular, the extended Derjaguin–Landau–Verwey–Overbeek (XDLVO) theory proved that after introducing GO/rGO into PPy membrane, the enhanced hydrophilicity and Zeta potential, as well as the weakened roughness, led to more positive van der Waals, Lewis acid-base and electrostatic interfacial force, that was, better anti-fouling property, which indicated an extremely bright future in the design of anti-fouling membranes.

Preparation of α-alumina/γ-alumina/γ-alumina-titania ceramic composite membrane for chloride ion removal

It is a universally acknowledged truth that ceramic membranes with high heat and chemical resistance play a crucial role in the nanofiltration (NF) process under harsh conditions. Although the ceramic membranes are challenging to use for salt filtration due to pore size and surface charge constraints. In this study, sol-gel and dip-coating techniques are used to make alumina–titania composite ceramic membranes with an γ-alumina interlayer for salt rejection. Then, particle size distribution was determined using dynamic light scattering (DLS), and membrane surface quality and morphology were examined using scanning electron microscopy (SEM). The microstructural properties of the membrane have been investigated using X-Ray Diffraction (XRD). A dead-end module is used to measure water permeability and salt rejection. After calcination at 450 °C, SEM shows the crack-free membrane surfaces. The interlayer and top layer membrane thicknesses were estimated to be 1.5 and 0.5 μm, respectively. In addition, XRD measurements show an alumina crystal structure for the interlayer and anatase, rutile, and alumina phases for the composite membranes. Finally, it was shown that the amount of chlorine rejection was pH-dependent, with the rejection rate increasing from 12.7% to 67% as the pH climbed from 4 to 12. Overall, this research provides a composite ceramic nanofiltration for high-pressure desalination, and it is shown that the membrane's surface does not alter after five cycles, which allows for a long-term chemical process and it could be a promising candidate in the wastewater treatment field.

Enriching volatile aromatic compounds of lavender hydrolats by PDMS/ceramic composite membranes

Lavender hydrolats are of low value due to its low aromatic compound concentration. This work applied polydimethylsiloxane (PDMS) /ceramic composite membranes to enrich volatile aromatic compounds (linalool, terpinen-4-ol, α-terpineol, and camphor) of lavender hydrolats for improving antioxygenic property. The effect of operating conditions on the enrichment was systematically studied. The results showed that the fluxes of the four aromatic compounds increased with the increase of feed concentration in the binary simulation system. The enrichment factor of camphor increased more significantly than other components with the increase of flow velocity and the total flux was basically unchanged in pervaporation. The flux of lavender hydrolats was 254.84 g·m-2·h-1, the enrichment factors of linalool, terpinen-4-ol, α-terpineol, and camphor were found to be 5.64, 4.56, 2.59 and 15.31 at 40 °C, respectively. The free radical scavenging rate of enriched lavender hydrolats was significantly improved. This work provides a basis for the recovery of aromatic compounds from lavender hydrates by using PDMS/ceramic composite membranes.

Preparation of superhydrophobic-superoleophilic ZnO nanoflower@SiC composite ceramic membranes for water-in-oil emulsion separation

Superhydrophobic-superoleophilic (SHB-SOL) wettability has proved its superiority in simultaneously enhancing the permeability and selectivity of porous interfacial materials for water-in-oil (w/o) emulsion separation. Here, ZnO nanoflower (NF) modified SiC (ZnO NF@SiC) composite ceramic membranes are reported through a chemical bath deposition method. ZnO NFs with different sizes were grown onto SiC grains forming tunable micro-nano hierarchical structures on the membrane surfaces. After n-octyltriethoxysilane grafting, all the composite ceramic membranes exhibit outstanding SHB-SOL wettability (water contact angle > 150° and sliding angle SA < 10°). The ZnO NF@SiC membrane owning a middle-sized ZnO NF displays the highest SHB-SOL property. When used for w/o emulsion separation, the SHB-SOL ZnO NF@SiC membranes show significantly improved oil flux and water rejection compared with the pristine and the sole silane grafted SiC membranes. The water rejection of the optimal membrane for 1000 ppm water-in-hexane emulsion is ∼99% and the initial state oil flux is ∼1300 L·m−2·h−1 under a transmembrane pressure of 1 bar, which is relatively competitive among the reported hydrophobic ceramic membranes. The mechanisms of surface hierarchical structures, wetting behavior and separation performance are further revealed. This work may offer new insights into preparing SHB-SOL ceramic membranes for practical w/o emulsion separation.

Modified ceramic membrane with pH/ethanol induced switchable superwettability for antifouling separation of oil-in-acidic water emulsions

Nowadays, oily wastewater is a harmful pollutant to the environment. Membranes with switchable wettability have great advantages in the oil–water separation. Herein, a novel ceramic composite membrane with switchable superwettability is fabricated by combining a dopamine-assisted nanoparticle coating process and a chemical grafting of copolymers with responsive groups. FESEM, XPS, FTIR, TG and contact angle measurements confirm the success of each surface modification steps. The as-prepared membranes transform from superhydrophobicity in air to superhydrophilicity in acidic aqueous solution (pH = 1) and recover to superhydrophobicity after immersion in ethanol. This superhydrophobicity-superhydrophilicity translation can repeat cyclically. The superwettability switchable membranes can effectively separate oil–water mixture and emulsions. Furthermore, good antifouling property of the composite membrane in filtration of oil-in-acidic water emulsions (pH = 1) has also been obtained. All these results show that this kind of ceramic composite membranes would have important applications in oil pollution control and industrial wastewater treatment.

A Simple Approach to Fabricate Composite Ceramic Membranes Decorated with Functionalized Carbide-Derived Carbon for Oily Wastewater Treatment.

Membrane-based oil–water separation has shown huge potential as a remedy to challenge oily wastewater with ease and low energy consumption compared to conventional purification techniques. A set of new composite ceramic membranes was fabricated to separate surfactant-stabilized oil/water (O/W) emulsion. Carbide-derived carbon (CDC) was functionalized by 3-aminopropyltriethoxy silane (APTES) and subsequently deposited on a ceramic alumina support and impregnated with piperazine as an additional amine. The APTES functionalized CDC-loaded membrane was then crosslinked using terephthalyol chloride (TPC). Different loadings of functionalized CDC (50 mg, 100 mg and 200 mg) were employed on the ceramic support resulting in three versions of ceramic membranes (M-50, M-100 and M-200). The fabricated membranes were thoroughly characterized by Scanning electron microscopy (SEM), X-ray diffraction (XRD), Attenuated total teflectance Fourier transform infrared (ATR-FTIR) spectroscopy, Energy dispersive x-ray spectroscopy (EDX) and elemental mapping. The highest permeate flux of 76.05 LMH (L m−2 h−1) at 1 bar using 67.5 ppm oil-in-water emulsion (as feed) was achieved by the M-50 membrane, while an oil separation efficiency of >99% was achieved by using the M-200 membrane. The tested emulsions and their respective permeates were also characterized by optical microscopy to validate the O/W separation performance of the best membrane (M-100). The effect of feed concentration and pressure on permeate flux and oil–water separation efficiency was also studied. A long-term stability test revealed that the M-100 membrane retained its performance for 720 min of continuous operation with a minor decrease in permeate flux, but the O/W separation efficiency remained intact.

Composite ceramic membrane containing titanium carbide as an active layer: Fabrication, characterization and its application in oil/water separation

Treatment of oily wastewater such as the produced water (PW) generated by oil and gas industries remains a pressing challenge. To mitigate this problem, a new ceramic membrane was fabricated for the efficient separation of an oil-in-water emulsion. The key component in this membrane is the titanium carbide (TiC) selective layer which was affixed onto an alumina ceramic support through interfacial polymerization (IP). The merits of the fabricated TiC@Alumina membrane were thoroughly characterized by different techniques and tested for the separation of oil/water (O/W) emulsion. A permeate flux of 591 LMH was achieved at a pressure of 8 bar. The membrane achieved a separation efficiency of > 99 % for all of the tested O/W emulsions (125 ppm, 250 ppm, and 500 ppm). The long-term stability test revealed that the composite membrane maintained excellent separation efficiency (>99 %) for 360 min.