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Many researchers used some models based on the assumption of spherical in shape particles. Particles shape is important and should be considered in models. In this work, a new model was used for prediction of gas permeability through the Mixed Matrix Membranes (MMMs). The effects of particles shape and undesirable defects (polymer chain rigidification, partial pore blockage and void formation) were introduced to the model simultaneously. The model was employed to predict some experimental data. The results showed that the less average absolute relative error (AARE) of the model for the MMMs were about 0.73–31.53%. [ABSTRACT FROM PUBLISHER]

In the current investigation, separation performance of poly (Ether Block Amid), PEBA (grade 1657), membrane was improved via incorporation of SiO 2 nanoparticles into the polymeric matrix. In order to attain excellent dispersion of SiO 2 nanoparticles within the polymeric matrix, a chemical surface modification was performed via esterification reaction between the nanoparticles and cis-9-octadecenoic acid (OA). To the best of our knowledge; there is no investigation on employing this type of modification for preparation of SiO 2 /polymer nanocomposite membranes. Permeation, sorption and diffusion coefficients of pure gases, CO 2 , H 2 , CH 4 and N 2 , through the prepared neat and the nanocomposite membranes were studied at temperature of (T = 25 °C) and pressure of (P = 2 bar). The results showed that, with increasing the loading content of nanoparticles from 0 wt% (the neat PEBA membrane) to 8 wt%, ideal permeation selectivity values of CO 2 /H 2 , CO 2 /CH 4 and CO 2 /N 2 improve from 9, 18 and 55 to 17, 45 and 124, respectively. [ABSTRACT FROM AUTHOR]

In this study, the morphological and separation characteristics of PVA membranes incorporated with functionalized CNTs are reported. CNTs was extensively characterized using TGA, FESEM, and TEM. The physicochemical properties of PVA-CNTs membranes were characterized using FESEM, tensile test, DSC, and XRD. DSC measurements showed an increase in melting and glass transition temperature, implying enhancement of polymer chains compacting. XRD analysis confirmed the results of DSC and showed that CNTs can promote crystallinity of the PVA membranes. In addition, tensile measurements revealed that incorporating CNTs into the PVA membranes improves their mechanical properties. The synthesized nanocomposite membranes were then evaluated in pervaporation (PV) dehydration of isopropanol (IPA). The separation results showed that incorporating CNTs into the PVA membranes significantly increases water selectivity of the PVA membranes. This can be attributed to the fact that incorporating CNTs compacts and rigidifies PVA matrix and decreases its free volume. Furthermore, permeation of water molecules through the nanocomposite membranes decrease as a result of the polymer chains rigidification. Effects of feed composition and temperature on PVA-CNTs nanocomposite membranes were investigated. Besides, effects of CNTs content on permeation properties and activation energies of PVA membranes were evaluated. [ABSTRACT FROM PUBLISHER]

Abstract: Zeolite hydroxysodalite (HS) was synthesized successfully by hydrothermal method using the natural kaolin. In the first step, kaolin has been calcined at 700°C to the metakaolinite phase. As a second step, the zeolitisation experiments have been carried out under hydrothermal conditions. The metakaolinite obtained has been reacted with NaOH solutions in autoclaves at 100°C. The crystal species were characterized by X-ray diffraction (XRD) patterns and morphology of the supports subjected to crystallization was characterized by Scanning electron microscopy (SEM). Performance of the hydrophilic Nano zeolite membranes during separation of water/Ethanol mixtures was evaluated. These membranes showed very high selectivity of water for water/Ethanol mixtures. Separation factor as high as 10,000 was obtained for ethanol feed concentration of 90%. Total mass flux was also obtained 0.959kg/m2.h. [Copyright &y& Elsevier]

Abstract: Dehydration of solvents using hydrophilic polyvinylalcohol pervaporation membranes is a well-established technology. However, these polymeric membranes may not be suitable for applications involving high water concentrations or applications containing harsh solvents like unsymmetrical dimethylhydrazine (UDMH) due to membrane stability problems and swelling effects. The recent development of solvent and temperature-resistant, hydrophilic zeolite Hydroxysodalite (HS) membranes has made it possible to overcome the above limitations of hydrophilic polymeric membranes. Zeolite membranes have uniform and molecular-sized pores, and they separate molecules based on differences in the molecules'' adsorption and diffusion properties. Strong electrostatic interaction between ionic sites and water molecules (due to its highly polar nature) makes the zeolite HS membrane very hydrophilic. Zeolite HS membranes are thus well suited for separating liquid-phase mixtures by pervaporation. In this study, experiments were conducted with various UDMH–water mixtures (1–20wt.%) at 25°C. Total flux for UDMH–water mixtures was found to vary from 0.323 to 0.214kg/m2 h with increasing UDMH concentration from 1 to 20wt.%. Ionic sites of the HS zeolite matrix play a very important role in water transport through the membrane. These sites act both as water sorption and transport sites. Surface diffusion of water occurs in an activated fashion through these sites. The precise nanoporous structure of the zeolite cage helps in a partial molecular sieving of the large solvent molecules leading to high separation factors. A comparison between experimental flux and calculated flux using Stephan Maxwell (S.M.) correlation was made and a linear trend was found to exist for water flux through the membrane with UDMH concentration. [Copyright &y& Elsevier]

In this research, mass transport in pervaporation (PV) process of isomeric xylenes (para_xylene and ortho_xylene) was investigated by means of the resistances-in-series model. In order to obtain necessary data for the analysis, some experimental studies on separation of the xylene mixtures using a poly (vinyl alcohol) (PVA) membrane were performed. Influence of operating conditions such as para_xylene concentration in the feed and permeate pressure on the membrane performance and also the transport resistances in different layers of membrane was examined. Finally, the impact of CBr4 (Carbon tetrabromide) on the membrane performance was evaluated. The results implied that by adding CBr4 to the feed, more ortho_xylene in the permeate can be collected, because CBr4 combines with para_xylene molecules, thus ortho_xylene molecules preferably pass through the membrane rather than para-xylene molecules. The mathematical model was found to be very accurate and could be employed for prediction of PV of isomeric xylenes. [ABSTRACT FROM AUTHOR]

Abstract: Zeolite membranes have been extensively researched for many industrial separations via gas permeation and liquid pervaporation processes. General separation mechanisms in zeolite membranes include molecular sieving and competitive adsorption and diffusion. Recently, the possibility of using zeolite membranes to remove ions from aqueous solutions by reverse osmosis (RO) has been explored. RO desalination by zeolite membranes may offer an alternative for some difficult water treatment processes such as concentration of low-level radioactive wastewater and desalination of high-concentration organic water produced in oil and gas operations where conventional technologies, including polymeric RO membranes, are either inapplicable or inefficient. MFI zeolite has an effective intracrystal nanopore diameter of 0.51 nm, which is smaller than the sizes of hydrated ions involved in the current systems. As a result, complete rejection of hydrated ions can occur using MFI zeolite membranes. In this research, mullite-supported MFI zeolite membranes were synthesized via the in situ crystallization method. Hydrothermal treatment was conducted in an autoclave at autogenous pressure. The membranes were made by a single hydrothermal treatment and characterized by X-ray diffraction and scanning electron microscope after calcination. [Copyright &y& Elsevier]

Abstract: Water/unsymmetrical dimethylhydrazine (UDMH) mixtures were separated at ambient temperature and atmospheric pressure by pervaporation (PV) using NaA zeolite membranes. Effects of crystallization time and temperature on the membrane performance were studied. These membranes showed very high selectivity of water for water/UDMH mixtures. Separation factor as high as 52000 was obtained for UDMH feed concentration of 5%. Total mass flux was also obtained up to 3.95kg/m2 h. The results confirm the superior performance of the zeolite membranes for dehydration of water/UDMH mixtures due to their uniform nanopores. [Copyright &y& Elsevier]

Morteza Asghari, Toraj Mohammadi, Armin Samimi and Majid Fouladi, Research Centre for Membrane Separation Processes, Faculty of Chemical Engineering, Iran University of Science and Technology, Narmak, Tehran, Iran, and Reza Fareghi Alamdari and Farima Agend, Department of Chemistry and Chemical Engineering, Faculty of Material and Chemical Engineering, Malek-e-Ashtar University of Technology, Lavizan, Tehran, Iran The separation of volatile organic compounds using membranes has been suggested as an innovative treatment process in environmental applications. This study provides details of the synthesis and characterisation of a zeolite membrane that potentially could be used for this purpose. Initially, a cation K+-exchange treatment was performed on prepared NaX powder and a three-layer, supported faujasite NaX membrane was fabricated. An ion-exchange process similar to that performed on the powder was then applied to the zeolite membrane. [Copyright &y& Elsevier]

Selective and simultaneous separation of H2S and CO2 from CH4 was accomplished in a hollow‐fiber membrane contactor (HFMC). The absorption of both H2S and CO2 using an aqueous solution of methyldiethanolamine (MDEA) was almost complete and acid gases were totally removed. Despite the large difference between H2S and CO2 concentrations, the rate of H2S absorption was not significantly influenced by CO2 absorption. The independent effect and interactions of several process variables on the separation performance of H2S and CO2 were investigated. The results indicated that the membrane contactor could be a highly efficient choice for removal of almost all H2S in the presence of a large CO2 content even at high gas/liquid flow ratio. The selectivity of H2S was about three times higher compared to the conventional absorption packed towers. Selective and simultaneous removal of H2S and CO2 from CH4 by hollow‐fiber hydrophobic membrane contactors is introduced. The removal performances of H2S and CO2 using an aqueous methyldiethanolamine solution were much higher than those reported for conventional packed towers. The membrane contactor is a highly efficient tool for removal of almost all H2S in the presence of a large CO2 content. [ABSTRACT FROM AUTHOR]

In this work, the response surface methodology (RSM) based on the central composite design (CCD) was used to examine effects of different gamma alumina (γ-AlO) loadings (0 to 8 wt.%) and various polyethylene glycol 1000 (PEG1000) contents (0 to 40 wt.%) as parameters on membrane preparation. Accordingly, pure carbon dioxide (CO) and methane (CH) gasses permeability and ideal CO/CH selectivity values were considered as responses. Poly (ether block amide) 1657 (Pebax1657) was used as the base polymer matrix for the membranes fabrication. The neat Pebax1657 membrane was prepared via solution casting-solvent evaporation method and the other membranes were prepared via solution blending technique. Analysis of variance (ANOVA) was used to analyze the experiments statistically and the results indicated that the optimized amounts of γ-AlO nanoparticles and PEG1000 in order to enhance both CO permeability and ideal CO/CH selectivity were 8 wt.% and 10 wt.%, respectively. Additionally, a comparison between the separation performance of the neat membrane, the nanocomposite membrane with the optimum amount of γ-AlO nanoparticles, the blended membrane with optimum amounts of PEG1000, and the blended nanocomposite membrane with optimum amounts of γ-AlO nanoparticles and PEG1000 was presented. The obtained gas permeation results showed that the blended nanocomposite membrane exhibits the highest CO/CH separation performance compared to the neat Pebax membrane. [ABSTRACT FROM AUTHOR]

The present research investigates deeply the effect of 1-ethyl-3 methylimidazolium tetrafluoroborate ([Emim][BF 4 ]) ionic liquid on separation performance and transport properties of poly(ether-b-amide6) (Pebax1657) at different operating pressures from 2 to 20 bar and temperatures from 25 to 65 °C. [Emim][BF 4 ] showed interesting separation factor for CO 2 /light gases as a solvent and it was expected that its addition to Pebax1657 leads to more amorphous structure, thereby increasing diffusion and permeability of gases. [Emim][BF 4 ] was added to the polymer solution up to 100 wt% of Pebax1657 weight and permeation coefficients of CO 2 , H 2 , CH 4 and N 2 through the prepared membranes were measured. The results showed remarkable increment in permeation of all the tested gases, particularly CO 2 and ideal selectivity of CO 2 /H 2 enhanced significantly due to high solubility selectivity of the added compound. Effect of operating conditions on solubility coefficients was also investigated; thus sorption isotherms and activation energies of permeability, solubility and diffusion were calculated. In addition, the membranes were characterized by SEM, DSC, FT-IR spectroscopy and Tensile analysis to inspect changes in their physical and thermal properties, precisely. [ABSTRACT FROM AUTHOR]

Abstract: The effect of silica addition on the photocatalytic and separation properties of mesoporous titania–silica membranes was investigated. Macroporous α-alumina support was used as substrate, and intermediate layer was obtained by deposition and calcination of the colloidal titania sol on the substrate. Then, titania and titania-5% silica polymeric sols were prepared for deposition on the interlayer as membrane top layer. The samples were characterized by DLS, TG-DTA, XRD, FTIR, BET, FESEM, TEM and AFM. The photocatalytic capability of the membranes was evaluated using methyl orange photo-degradation. The mesoporous composite membrane was prepared with the average pore size of 3.94nm. The dye removal efficiency of the titania–silica membrane has been determined to be 63% after 60min UV-irradiation. By coupling separation process with photocatalytic technique, the removal efficiency was improved up to 94%. The synthesized titania–silica membrane showed a great potential due to its multifunctional capability for water treatment. [Copyright &y& Elsevier]

In this paper, the effects of in-line coagulation on permeation fiux (PF), fouling resistance (FR), and total organic compound (TOC) rejection (R) of synthesized mullite ceramic membranes during treatment of oily wastewater in coagulation - MF hybrid process were investigated. Four coagulant ((ferrous chloride (FeCl2.4H2O), ferrous sulphate (FeSO4.7H2O), aluminum chloride (AlCl3.6H2O) and aluminum sulphate (Al2(SO4)3.18H2O)) plus equal concentration of lime in the form of calcium hydroxide (Ca(OH)2) were evaluated in the coagulation - MF hybrid process at different concentrations (Oppm, 25ppm, 50ppm, and lOOppni). The results showed that coagulation can affect the membrane filtration by changing characteristics of the oil droplets. Coagulant agents improve the membrane performance at low dosage (25 ppm) for aluminum chloride and mean dosage (50 ppm) for ferrous chloride, ferrous sulphate, and aluminum sulphate. At the best conditions (50 ppm ferrous sulphate), PF increased from 2.22 × 10-5 to 2.76 × 10-5 (m3/m2s), FR decreased from 4.2 × 1012 to 5.55 × 1011(m-1), and R increased from 93.8% to 97.1%. [ABSTRACT FROM AUTHOR]

Abstract: The transport properties of gases in polydimethylsiloxane (PDMS)/zeolite A mixed matrix membranes (MMMs) were determined based on pure gas permeation experiments. MMMs were prepared by incorporating zeolite 4A nanoparticles into a PDMS matrix using a new procedure. The permeation rates of C3H8, CH4, CO2, and H2 were evaluated through a dense homogeneous pure PDMS membrane and PDMS/4A MMMs to assess the viability of these membranes for natural gas sweetening and hydrogen purification. SEM investigations showed good adhesion of the polymer to the zeolite in MMMs. Permeation performance of the membranes was also investigated using a laboratory-scale gas separation apparatus and effects of feed pressure, zeolite loading and pore size of zeolite on the gas separation performance of the MMMs were evaluated. The MMMs exhibited both higher selectivity of H2/CH4 and H2 permeability as compared with the neat PDMS membrane, suggesting that these membranes are very promising for gas separations such as H2/CH4 separation. [Copyright &y& Elsevier]

In this work, separation of toluene/n-heptane mixtures via pervaporation using a composite membrane was investigated. Effects of operating conditions such as feed temperature, feed composition and downstream pressure on the membrane performance were studied. Experimental results were obtained at different feed compositions (10-40 wt.%), operating temperatures (25-85°C) and downstream pressures (2-32 mbar g). The membrane selectivity for toluene was found to be greater than that for n-heptane. According to the results, it was observed that increasing toluene concentration in the feed and operating temperature enhance the membrane swelling and increase the polymeric chain mobility. Therefore, feed concentration and temperature have the same effects on toluene selectivity and permeation flux of the membrane. Permeation flux increases and toluene selectivity decreases with increasing feed concentration and temperature. In contrary, the membrane performance enhances with decreasing downstream pressure. It was found out that for a feed with 10wt.% of toluene, at a temperature of 85°C and a downstream pressure of 2 mbar g, the highest PSI value of 18.371 kg/m² h (in which permeation flux = 4.610 kg/m² h and toluene selectivity = 4.985) is achieved. [ABSTRACT FROM AUTHOR]

In this paper, a new polydimethylsiloxane (PDMS) membrane was synthesized and its ability for separation of heavier gases from lighter ones was examined. Sorption, diffusion, and permeation of H2, N2, O2, CH4, CO2, and C3H8 in the synthesized membrane were investigated as a function of pressure at 35°C. PDMS was confirmed to be more permeable to more condensable gases such as C3H8. This result was attributed to very high solubility of larger gas molecules in hydrocarbon-based PDMS in spite of their low diffusion coefficients relative to small molecules. The synthesized membrane showed much better gas permeation performance than others reported in the literature. Increasing upstream pressure increased solubility, permeability and diffusion coefficients of C3H8, while these values decreased slightly or stayed constant for other gases. Local effective diffusion coefficient of C3H8 and CO2 increased with increasing penetrant concentration which indicated plasticization effect of these gases over the range of penetrant concentration studied. C3H8/gas solubility, diffusivity and overall selectivities also increased with increasing feed pressure. Ideal selectivity values of 4, 13, 18, 20, and 36 for C3H8 over CO2, CH4, H2, O2, and N2, respectively, at upstream pressure of 7 atm, confirmed the outstanding separation performance of the synthesized mebrane. [ABSTRACT FROM AUTHOR]

Abstract: In this study, cellulose acetate (CA) ultrafiltration (UF) membranes were prepared using the phase inversion method. Effects of CA and polyethylene glycol (PEG) concentrations in the casting solution and coagulation bath temperature (CBT) on morphology of the synthesized membranes were investigated. Based on L 9 orthogonal array of Taguchi experimental design 18 membranes were synthesized (with two replications) and pure water permeation flux through them were measured. It was found out that increasing PEG concentration in the casting solution and CBT, accelerate diffusional exchange rate of solvent 1-methyl-2-pyrrolidone (NMP) and nonsolvent (water) and consequently facilitate formation of macrovoids in the membrane structure. Increasing CA concentration, however, slows down the demixing process. This prevents instantaneous growth of nucleuses in the membrane structure. Hence, a large number of small nucleuses are created and distributed throughout the polymer film and denser membranes are synthesized. Rate of water flux through the synthesized membranes is directly dependent on the size and number of macrovoids in the membrane structure. Thus, maximum value of flux is obtained at the highest levels of PEG concentration and CBT (10wt.% and 23°C, respectively) and the lowest level of CA concentration (13.5wt.%). Analysis of variance (ANOVA) showed that all parameters have significant effects on the response. However, CBT is the less influential factor than CA and PEG concentrations on the response (flux). [Copyright &y& Elsevier]

Abstract: The effect of factors influencing the on separation of water in oil emulsions was investigated. A hydrophobic PTFE membrane with 0.45 μm pore size was used. Gas oil, distilled water and Span 80 were selected as continuous phase, dispersed phase and emulsifier, respectively. The prepared emulsions contained 5–20 vol% water and 0.2–0.8 vol% emulsifier. Taguchi experimental design was used to plan a minimum number of experiments. A L16 orthogonal array (Five factors in four levels) was employed to evaluate effect of water and emulsifier content in feed, operating pressure, operating temperature and feed residence time in module on the response (permeate flux and water content in permeate). Preliminary experiments were carried out to identify critical feed conditions. It was shown that increasing emulsifier content and decreasing water content feed decrease permeate flux and water content in permeate. Obviously, minimum and maximum permeate flux was observed when emulsifier and water content in feed were held at their maximum and minimum levels, respectively. It was found that decreasing residence time to its lower limit causes permeate flux to increase. It was also found that, contrary to other microfiltration processes, temperature is an effective factor on the response and increasing pressure decreases permeate flux. Analyzing of variance was finally applied to determine the optimum operating condition as well as contribution of each factor on the response. [Copyright &y& Elsevier]

In this study graphene oxide (GO) was functionalized using amine and used as inorganic filler for preparation of mixed matrix membranes (MMMs) using polyethersulfone (PES) as polymer matrix. These membranes were applied for separation of CO 2 from CH 4 . The effects of filler loading, feed temperature and feed pressure on CO 2 /CH 4 selectivity of the MMMs were investigated. The results indicated that addition of amine-functional graphene oxide in the casting solution enhanced the membrane gas permeance and CO 2 /CH 4 ideal selectivity. SEM images and FTIR analysis were used to characterize the filler particles and the synthesized membranes. SEM images also indicated that, there were appropriate distribution particles in the polymer matrix. Among different types of artificial neural networks (ANN), radial basis function (RBF) network was used to model performance of the MMMs. For training of the RBF model, 70% of the collected experimental data was used and the model was tested using the rest 30% data. The mean square error (MSE) and correlation coefficient ( R ) were used for investigating performance of the RBF model. The results showed that the RBF model is suitable and efficient for predicting performance of the PES/amine-functional graphene oxide (AFGO) MMMs. [ABSTRACT FROM AUTHOR]

Poly(tetramethylene ether) glycol (PTMEG) is used to fabricate Pebaxl657/PTMEG blended membranes for CO2 separation from H2, N4 and CH4. Permeation of the pure gases was measured at different operating temperatures from 25 to 55 °C and pressures from 4 to 16 bar. The solubility and diffusion coefficients of the tested gases were also measured at 4 bar. Permeation results showed an increment in the tested gases along with enhancement in CO2/H2 permselectivity. However, CO2/N2 and CO2/CH4 permselectivity did not improve. The membranes were characterized by SEM, DSC, FTIR and tensile analysis and considerable changes in morphological, thermal and structural properties of the membranes were observed. [ABSTRACT FROM AUTHOR]

Abstract: Separation of H2S from binary mixtures of H2S/CH4 using vertically aligned carbon nanotube membranes fabricated in anodic aluminum oxide (AAO) template was studied experimentally. Carbon nanotubes (CNTs) were grown in five AAO templates with different pore diameters using chemical vapor deposition, and CNT/AAO membranes with tubular carbon nanotube structure and open caps were selected for separation of H2S. For this, two tubular CNT/AAO membranes were fabricated with the CNT inner diameters of 23 and 8nm. It was found that permeability and selectivity of the membrane with inner diameter of 23nm for CNT were independent of upstream feed pressure and H2S feed concentration unlike that of CNT having an inner diameter of 8nm. Selectivity of these membranes for separation of H2S was obtained in the ranges of 1.36–1.58 and 2.11–2.86, for CNTs with internal diameters of 23 and 8nm, respectively. In order to enhance the separation of H2S from H2S/CH4 mixtures, dodecylamine was used to functionalize the CNT/AAO membrane with higher selectivity. The results showed that for amido-functionalized membrane, both upstream feed pressure and H2S partial pressure in the feed significantly increased H2S permeability, and selectivity for H2S being in the range of 3.0–5.57 respectively. [Copyright &y& Elsevier]

Abstract: A large amount of oily wastewaters is generated by industrial sources. Oil-in-water emulsions are the most serious pollutants for which current treatment technologies are often costly and ineffective. In recent years, membrane processes have been applied for oily wastewater treatment. Microfiltration (MF) was successfully used in oil-in-water separations. In this research, investigations were carried out for treatment of an oily wastewater. A tubular ceramic MF (α-Al2O3) system was employed for treatment of a typical oily wastewater comes from API effluent of Tehran refinery. This system could produce a permeate with oil and grease content of 4mg/L that meets the National Discharge Standard and exhibited TOC removal efficiency higher than 95%. Also, effects of operating parameters such as transmembrane (TMP), cross flow velocity (CFV) and temperature on permeate flux, TOC removal efficiency and fouling resistance (FR) were investigated. The recommended operating conditions are TMP of 1.25bar, CFV of 2.25m/s and temperature of 32.5°C. In this system, backwashing was used to remove oil droplets and particulates that block the membrane pores, and the results showed that backwashing could prevent permeate flux decline significantly. Based on the results, this system was proposed to be replaced with the conventional wastewater treatment method. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, results of an experimental study on separation of oil from actual and synthetic oily wastewaters with mullite and mullite–alumina tubular ceramic membranes are presented. Mullite and mullite–alumina microfiltration (MF) symmetric membranes were synthesized from kaolin clay and α-alumina powder. The effects of different operating parameters such as pressure (0.5–4bar), cross flow velocity (0–2m/s), temperature (15–55°C), oil concentration (250–3000ppm) and salt concentration (0–200g/L) on permeation flux (PF), fouling resistance (FR), fouling and rejection (R) of mullite and mullite–alumina membranes for treatment of synthetic wastewaters were investigated. In order to determine the best operating conditions, 250–3000ppm condensate gas in water emulsions was employed as synthetic oily wastewaters using mullite membrane. At the best operating conditions (3bar pressure, 1.5m/s cross flow velocity and 35°C temperature), performance of mullite and mullite–alumina membranes for treatment of real and synthetic wastewaters were also compared. The results for treatment of emulsions showed that the mullite ceramic membrane has the highest R (93.8%) and the lowest FR (28.97%). Also, the mullite–alumina ceramic membrane with 75% alumina performs high PF (244L/m2 h) and low R (81.3%). Also for all the membranes, R for the real wastewater is lower than that for the synthetic wastewaters. [Copyright &y& Elsevier]