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The phenomenon of phase inversion occurs in liquid-liquid dispersions foundin a variety of chemical engineering fields. From simple oil-water mixtures tocomplex polymeric systems, the operating variables that affect this physicalphenomenon are discussed in this work. The contribution on this matter by alarge number of researchers is critically assessed, outlining both coherent andconflicting results. A detailed review of the mechanisms by which phase inversiontakes place is also provided. While this subject has been studied for thepast 50 years, this multivariate nonlinear process is not yet comprehensivelyunderstood, and this review article aims to describe the conclusions so farreached to provide insight for future research. Fil: Maffi, Juan Martín. Instituto Tecnológico de Buenos Aires; Argentina Fil: Meira, Gregorio Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Estenoz, Diana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina

Recent trends in preservation of processed foods involve the use of natural compounds, rather than chemically synthesized additives, to simultaneously confer antimicrobial properties and prevent fat oxidation. In this regard, black pepper essential oils, due to its diversity in biological activities, have been increasingly popular. The compounds are often used in relatively low amounts and in the form of nanoparticles to permit well blending into foods or uniform dispersion on the surface of fresh meat. The purpose of this study is to determine experimental parameters of a nano‐emulsion formation process from black pepper essential oil via the phase inversion temperature (PIT) technique. The study results showed that the system achieved the optimal nano‐emulsion under following condition: the ratio by weight of water: Tween‐80: oil = 86:9.7:4.3, the stirring speed of nano‐emulsions at 500 rpm for 45 min (heating at 75°C for 30 min and then rapidly cooling at 5°C for 15 min).

The phase inversion (PI) during the bulk polymerization ofthe styrene?polybutadiene system (high impact polystyrenemanufacturing process) is empirically and theoreticallystudied in this article. In the experimental work, a series ofreactions were performed with benzoyl peroxide as initiatorand at temperatures considered of industrial interest (80Cand 90C), varying also the reactor stirring level. PI wasdetermined by offline viscosity measurements and verifiedby scanning transmission electron microscopy. The rheologicalbehavior of each reacting system was analyzed andan empirical correlation to predict its apparent viscosityfrom fundamental reaction parameters was derived. Thiswas achieved successfully for both before and after the PIpoint. Fil: Maffi, Juan Martín. Instituto Tecnológico de Buenos Aires; Argentina Fil: Casis, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Acuña, Pablo. Centro de Investigacion En Quimica Aplicada, Saltillo; México Fil: Morales, Graciela. Centro de Investigacion En Quimica Aplicada, Saltillo; México Fil: Estenoz, Diana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina

The aim of this study was to develop a fast and an efficient method to determine the Hydrophile-Lipophile Balance (HLB) number of cosmetic and pharmaceutics surfactants.This method is based on the deviation of the phase inversion temperature induced by the addition of the test compound, with respect to the phase inversion temperature of a reference system, which includes an ethoxylated surfactant. This method is called PIT-deviation.Three calibration curves are set up with three reference ethoxylated surfactants. These calibration curves make it possible to evaluate the interfacial behaviour of certain chemicals. More particularly, these curves make it possible to easily determine the surfactant HLB.In this study, a fast and accurate method has been developed to determine the hydrophilic-lipophilic balance (HLB) number of amphiphilic chemicals. This new method can be applied to establish an HLB number of all commercial amphiphilic ingredients. Compounds which have a PIT-deviation close to zero are also discussed.Le but de cette étude était de développer une méthode rapide et efficace pour déterminer le nombre Hydrophiles-Lipophiles Balance (HLB) d'agents tensioactifs cosmétiques et pharmaceutiques. MÉTHODES: Cette méthode est basée sur le déplacement de la température d'inversion de phase induite par l'addition du composé à tester par rapport à la température d'inversion de phase d'un système de référence, comprenant un tensioactif éthoxylé. Cette méthode s'appelle PIT-déviation. RÉSULTATS: Trois courbes d'étalonnage sont établies avec trois tensioactifs éthoxylés de référence. Ces courbes d'étalonnage permettent d'évaluer le comportement interfacial de certains produits chimiques. Plus particulièrement, ces courbes permettent de déterminer facilement le HLB de tensioactif.Dans cette étude, une méthode rapide et précise a été développée pour déterminer le Hydrophile-Lipophile Balance (HLB) de produits chimiques amphiphiles. Cette nouvelle méthode peut être appliquée pour établir un HLB de tous les ingrédients amphiphiles. Les composés dont la PIT-deviation est proche de zéro sont également abordés.

In this work, ultrafiltration (UF) mixed matrix membranes (MMMs) incorporated with hydrophilic hydrous manganese oxide (HMO) nanoparticles were synthesized and used for the treatment process of a highly concentrated oily solution. The MMMs were fabricated via a phase inversion process and were characterized with respect to physiochemical properties and filtration performances. The results showed that the MMMs demonstrated higher water flux and better oil rejection rates compared to the control membrane (without HMO incorporation) when tested at three different oily solutions with oil concentration in the range of 5000–15?000?ppm. The membrane incorporated with the highest amount of HMO (labelled as MMM-2) in particular showed the best results even when subjected to 15?000?ppm oily solution filtration, recording water flux of 32.2 L/m2?·?h?·?bar and oil rejection of 82?%. The enhanced performance can be attributed to improved surface hydrophilicity coupled with better structural integrity and higher porosity that contributed to lower degree of oil molecules deposition and greater water transport rate. It was also reported that with the use of a feed spacer during the filtration process, the degree of flux deterioration of MMMs could be further reduced without compromising rejection. The findings of this work indicated the potential of MMMs for the treatment of highly concentrated oily effluent produced from industries, by producing permeate of high quality at reasonably good water permeability.

Processing of a high glass transition (Tg) polymer such as polyethersulfone (PES; Tg = 225°C) poses a challenge as it requires high processing temperatures or sometimes toxic solvents. In this work, we report of a facile process using superheated water (shH2O) and supercritical carbon dioxide (scCO2) co-media. PES solids were foamed in the scCO2/shH2O co-media or scCO2 alone in a batch process at different temperatures. The scCO2/shH2O produced a synergistic effect and achieved PES foams even at processing temperatures as low as 85°C below the nominal Tg; whereas, scCO2 alone required higher processing temperatures. Moreover, the scCO2/shH2O co-media produced highly porous PES foams that were at least 23% higher in porosity than what was obtained using scCO2 alone. In addition, the scCO2/shH2O produced open cell foams at some processing conditions; whereas, scCO2 produced closed cell morphologies. Since both CO2 and H2O are innocuous, this approach has potential for use in the preparation of ultrafiltration membranes, which currently require the use of toxic solvents for their fabrication by way of the phase inversion process. Moreover, the use of scCO2/shH2O is a cost-effective approach for the processing of high Tg polymers at significantly lower temperatures. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers

A micrometer scale method based on the principle of liquid rope coiling with the assistance of non-solvent induced phase inversion is introduced to fabricate YSZ coils. The YSZ coils with the filament diameter of several hundreds of micrometer exhibit stable spring properties and excellent elongation at failure. With the spring rate in the range of ~ 2 N/mm to ~ 21 N/mm and the elongation up to 4.36%, both the two properties can be effectively controlled and tailored since they both strongly depend on the geometric dimensions varied with the process parameters. Besides, the simple method provides an alternative method for the large-scale production and customization of ceramic coils with diverse applications. This article is protected by copyright. All rights reserved.

Solvent-free extrusion emulsification (SFEE) is a complex process using twin-screw extrusion to prepare solid-liquid dispersions of high viscosity polymers and has received little study to date on its inherent mechanisms. To gain rheological insights into the earliest stage of SFEE as the interfacial boundary between water and polymer grows, prior to phase inversion, an inline orifice-plate type viscometer is introduced to monitor transient behavior over a wide range of viscosities. The presented work examines rheological changes of a polyester-water system produced by varying two factors thought to significantly control the final state of the dispersion, specifically polar group contributions to surface energy and viscosity. A processing modifier was combined with the polyester to study the influence of these two factors. The inline viscometer revealed an abrupt transition in viscosity occurred with the developed state of water dispersion, confirming observations of a prior batch study. Analysis of the rheological response indicated that a higher polar surface energy contribution had the greatest influence on the state of this transition, and that a steeper transition was related to greater incorporation of water within the polyester matrix. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers

Graphene is known for its high surface‐area‐to‐mass ratio. However, for graphene to be used in engineering processes such as catalytic reactors or heat exchangers, high surface‐area‐to‐volume ratio is essential. Currently, graphene is only prepared in sheet form, which limits its surface‐area‐to‐volume ratio to around 200 m2 m−3. In this study, we propose and demonstrate a technique based on chemical vapour deposition (CVD) to realise graphene on a copper‐based micro‐tubular substrate to not only substantially increase its surface‐area‐to‐volume ratio to a value over 2000 m2 m−3, but also to eliminate maldistribution of flows commonly unavoidable in flat‐sheet configurations. Our approach uses a dual‐layer micro‐tubular substrate fabricated by a phase‐inversion facilitated co‐extrusion technique. In the substrate, a thin copper outer layer is employed to enable the CVD growth of graphene, and an inner Cu‐Fe layer is adopted to provide a strong mechanical support. Our study shows that this approach is feasible to produce graphene with a very high surface‐area‐to‐volume ratio for possible practical applications in catalytic reactors or heat exchangers, though problems such as the inter‐diffusion between the two metal layers and defects in graphene need to be further addressed. To the best of our knowledge, this study is the first attempt to prepare graphene with high surface‐area‐to‐volume ratio by a CVD route.

The purpose of this work was the preparation and characterization of polymeric membranes for the selective recognition of saccharides using molecular imprinting technology associated to phase inversion. A system able to bind saccharides with high selectivity is particularly important in the pharmaceutical sector, since some of these compounds are constituents of molecules which can exert serious toxic effects even at very low concentrations. Two polymeric matrices were prepared using poly(ethylene-co-vinyl alcohol) copolymers, with an ethylene molar content of 32% and 44%, and imprinted with two different saccharide molecules: maltose and 2-keto 3-deoxy-D-manno-octulosonate (KDO). Matrices imprinted against maltose and KDO showed an easy template extraction, high binding capability and satisfactory selectivity, particularly for matrix with an ethylene molar content of 44%.

The assembly of nanoparticles incorporating bacterial medium-chain-length poly-3-hydroxyalkanoates (mcl-PHA) via phase inversion emulsification (PIE) was investigated. Sequential addition of water into an agitated mixture of carrier oil (jojoba oil), nonionic surfactants (Cremophor EL and Span 80) and melted mcl-PHA triggered phase inversion of water-in-oil (W/O) to oil-in-water (O/W) emulsion. The emulsion inversion point (EIP) at 30% w/w of water content was determined by abrupt changes in viscosity and conductivity of the suspension. Concurrently, infrared transmittance of the O–H group of water, the C–O–C group of surfactants and the C–H group of alkane chain were practically identical while Small Angle X-ray Scattering indicated the presence of a bi-continuous/lamellar structure. The morphology of the emulsion changed, with increasing water content, from W/O to bi-continuous/lamellar structure and finally to O/W. mcl-PHA appears to form a bridging polymeric network, covering the nanoparticle with a protective layer for enhanced protection of the encapsulated compound. A hypothetical mechanism for the mcl-PHA-based nanoparticle assembly is also proposed.

In this work, porous structures of poly(L-lactic acid)-co-(tri-methylene-carbonate) (PLLA-co-TMC) were successfully fabricated using two experimental methods, that is, using supercritical CO2 as antisolvent and as foaming agent through the pressure induced phase separation technique. Considering the phase inversion method, the effect of the initial polymer concentration of the solution, pressure, and temperature on the morphology of the final porous structure (pore size, porosity, and cell density) was investigated. The L–L demixing process was suggested as the dominant mechanism for the phase separation and pore production. The temperature window, for which PLLA-co-TMC porous structures are successfully produced using the pressure induced phase separation technique, was determined at 150 and 210 bar. The effect of temperature on the final porous structure was investigated. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

The intrinsic properties of nanoscale active materials are always excellent for energy storage devices. However, the accompanying problems of ion/electron transport limitation and active materials shedding of the whole electrodes, especially for high-loaded electrode composed of nanoparticles with high specific surface area, bring down their comprehensive performance for practical applications. Here, this problem is solved with the as proposed “phase inversion” method, which allows fabrication of tricontinuous structured electrodes via a simple, convenient, low cost, and scalable process. During this process, the binder networks, electron paths, and ion channels can be separately interconnected, which simultaneously achieves excellent binding strength and ion/electron conductivity. This is verified by constructing electrodes with sulfur/carbon (S/C) and Li3V2(PO4)3/C (LVP/C) nanoparticles, separately delivering 869 mA h g−1 at 1 C in Li–S batteries and 100 mA h g−1 at 30 C in Li–LVP batteries, increasing by 26% and 66% compared with the traditional directly drying ones. Electrodes with 7 mg cm−2 sulfur and 11 mg cm−2 LVP can also be easily coated on aluminum foil, with excellent cycling stability. Phase inversion, as a universal method to achieve high-performance energy storage devices, might open a new area in the development of nanoparticle-based active materials.

The objective of this study was to fabricate dual-layer hollow fiber as a microreactor for potential syngas production via phase inversion-based co-extrusion/cosintering process. As the main challenge of phase inversion is the difficulty to obtain defect-free fiber, this work focuses on the effect of the fabrication parameters, that is, nonsolvent content, sintering temperature and outer-layer extrusion rate, on the macrostructure of the produced hollow fiber. SEM images confirm that the addition of nonsolvent has successfully minimized the finger-like formation. At high sintering temperature, more dense hollow fiber was formed while outer-layer extrusion rate affects the outer layer thickness.

Polyvinylidene fluoride (PVDF)/polyvinyl alcohol (PVA) ultrafiltration (UF) membranes were prepared via a phase inversion method employing the modification of carboxylated multiwalled carbon nanotubes (MWCNTs-COOH). Various contents of MWCNTs-COOHs (0.00–0.15 wt%, weight of casting solution) were added into PVDF/PVA/dimethyl sulfoxide systems for the fabrication of the plate UF membrane. Fourier transform infrared spectroscopy spectra identified the successful introduction of carboxyl through the CO peak at 1730 cm−1. Scanning electron microscopy images exhibited the external surface and the asymmetric morphology with the appearance of a sponge-like inner structure. Atomic force microscopy analysis determined the roughness values and rougher topography. The hydrophilicity of the composite membrane containing 0.09 wt% of MWCNTs-COOHs improved the most. This sample has the highest pure water flux, approximately doubled (126.6 L·m−2·h−1) compared to the PVDF/PVA membrane (68.6 L·m−2·h−1), an enhanced bovine serum albumin flux recovery rate, showing an increase of 17%, and the best fouling resistance ability. Meanwhile, the porosity and dynamic contactangle also indicate the enhancement of membrane hydrophilicity. Dextran (DEX) 600k rejection reached 91.0%. Break strength, elongation at break, and Young's modulus also had improvements of 60%, 215.5%, and 56.7%, respectively, when the MWCNTs-COOH content was 0.12 wt%. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Summary Organically modified halloysite nanotube (HNT) containing polysulfone (PSU) membranes were fabricated by the wet phase inversion method. Organic modification of HNT was carried out using telehelic polyetheramine inorder to overcome the poor dispersion of HNT in PSU matrix. Telehelic polyetheramine acts as a dispersing agent and a hydrophilic modifier. FTIR results revealed the hydrogen bond formation between –SO2 of PSU and –NH2 of modified HNT. Based on the obtained results of contact angle measurements, the wettability of membranes were found to increase with the weight percentage of HNT in the presence of polyetheramine. At higher loading of filler the water uptake was found to be increasing due to the aggregation of nanotubes. Porosity values substantiate the results obtained for contact angle and water uptake measurements. Thermogravimetric results showed that the thermal stability of polysulfone (PSU)/HNT nanocomposite membranes decreased when compared to neat PSU due to the presence of aliphatic chain of polyetheramine.

Sugarcane bagasse was used as a cellulose resource, and the transparent cellulose hydrogel films were obtained from the purified cellulose by phase inversion process without chemical cross-linking, when the dissolved cellulose in lithium chloride/N,N-dimethyl acetamide was transformed into the solid film. On these processes, bagasse was pre-treated by 10 wt% sodium hydroxide in the absence and presence of bleaching of 10 vol% sodium hypochlorite (NaOCl) solution in order to obtain cellulose fibers. Here, the bleaching temperature was varied from 40 to 50°C. The effect of pre-treatment conditions on the resultant cellulose solution and hydrogel films was investigated. It was seen that strong bleaching removed most of lignin component from the bagasse. However, viscosity and size exclusion chromatogram of the cellulose indicated that this operation decreased average molecular weight of the cellulose fibers from 2.1 × 106 to 4.8 × 105. These property changes of fibers also caused increase of water content and weakening of mechanical strength of the resultant hydrogels. In addition, scanning probe microscopy in wet state revealed that the porous fiber network structure in the hydrogel was greatly influenced by bleaching with NaOCl. The average pore size of fiber network was decreased from 8.1 to 5.9 nm as the NaOCl treatment was at 50°C, because of expanded fibers in the swollen hydrogel. Copyright © 2016 John Wiley & Sons, Ltd.

This work introduces a simplified methodology for measuring the characteristic curvature (Cc) of commercial alkyl ethoxylate nonionic surfactants using carefully selected reference surfactants and oils that produce rapid and well defined separations in salinity scans. The Cc of the commercial reference surfactants was calculated using optimal salinities (S*) obtained from solubilization parameter curves, from interfacial tensions (for a selected system), and from emulsion stability tests. The latter provided a fast detection of S*, in a matter of minutes. The calibrated Cc of the reference surfactants was subsequently used to measure the Cc of various commercial alkyl ethoxylate surfactants. The combination of mixtures of test and reference surfactants and emulsion stability tests produced reproducible Cc values that could be obtained with simple bottle tests and in a timely manner. The values obtained using this methodology were cross-checked, and proved to be consistent, when using different combinations of reference surfactants and oils, and when conducted by different individuals. The standard deviation of Cc from these measurements was typically ±0.2 Cc units, but it could be as large as 25 % of the Cc value for highly hydrophilic surfactants. After comparing the values of Cc obtained experimentally with values calculated from nominal structures (via a group contribution model) it became clear that there are differences between these values, likely because of the polydispersity of alkyl ethoxylate surfactants.

Polyamide-6 (PA6) submicron-sized spheres are prepared by two steps: (1) anionic ring-opening polymerization of ε-caprolactam in the presence of poly(ethylene glycol)-block-poly-(propylene glycol)-block-poly(ethylene glycol)(PEG-b-PPG-b-PEG) and (2) separation of PA6 spheres by dissolving PEG-b-PPG-b-PEG from the prepared blends. The PA6 microspheres obtained are regular spherical, with diameter ranging from 200 nm to 2 μm and narrow size distribution, as confirmed by scanning electron microscopy. By comparison with PA6/PS and PA6/PEG systems, it is denominated that the PEG blocks in PEG-b-PPG-b-PEG can effectively reduce the surface tension of PA6 droplets and further decrease the diameter of the PA6 microspheres. The PPG block in PEG-b-PPG-b-PEG can prevent the PA6 droplets coalescing with each other, and isolated spherical particles can be obtained finally. The phase inversion of the PA6/PEG-b-PPG-b-PEG blends occurs at very low PEG-b-PPG-b-PEG content; the PEG-b-PPG-b-PEG phase can be removed by water easily. The whole experiment can be finished in a short time (approximately in half an hour) without using any organic solvents; it is an efficient strategy for the preparation of submicron-sized PA6 microspheres.

The formation of stable emulsions in biphasic biotransformations catalyzed by microbial cells turned out to be a major hurdle for industrial implementation. Recently, a cost-effective and efficient downstream processing approach, using supercritical carbon dioxide (scCO2 ) for both irreversible emulsion destabilization (enabling complete phase separation within minutes of emulsion treatment) and product purification via extraction has been proposed by Brandenbusch et al. (2010). One of the key factors for a further development and scale-up of the approach is the understanding of the mechanism underlying scCO2 -assisted phase separation. A systematic approach was applied within this work to investigate the various factors influencing phase separation during scCO2 treatment (that is pressure, exposure of the cells to CO2 , and changes of cell surface properties). It was shown that cell toxification and cell disrupture are not responsible for emulsion destabilization. Proteins from the aqueous phase partially adsorb to cells present at the aqueous-organic interface, causing hydrophobic cell surface characteristics, and thus contribute to emulsion stabilization. By investigating the change in cell-surface hydrophobicity of these cells during CO2 treatment, it was found that a combination of catastrophic phase inversion and desorption of proteins from the cell surface is responsible for irreversible scCO2 mediated phase separation. These findings are essential for the definition of process windows for scCO2 -assisted phase separation in biphasic whole-cell biocatalysis.

Phase inversion is a powerful alternative process for preparing ultra-thin separators for various secondary batteries. Unfortunately, separators prepared from phase inversion generally suffer from uneven pore size and pore size distribution, which frequently results in poor battery performance. Here, a straightforward route is demonstrated to solve the drawbacks of phase-inversion-based separators for Li-ion batteries by means of directly incorporating 2D clay sheets in the skeleton of poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) with multiscale pore generation from a simple one-step solution coating method. Additionally generated pores by the inclusion of 2D nanosheets in PVdF-HFP skeletons, combined with the multiscale pores (several micrometers + sub-micrometers) originally generated by means of the controlled phase inversion, can generate additional ionic transport pathways, leading to Li-ion battery performances better than those of commercialized polyethylene separators. Moreover, the addition of extremely low contents of 2D clay sheets in PVdF-HFP separators allows thermally stable polymer separators to be realized.

BACKGROUND: Functionalized activated carbon (FAC) was prepared by immobilizing the activated carbon (AC) synthesized from Acacia fumosa seeds in cacium-alginate beads. Synthesized FAC has been blended with polyphenylsulfone (PPSU) in the composition of 0.25 to 1wt% with an increment of 0.25wt% to prepare composite membranes of PPSU/FAC by wet phase inversion method. The existence of FAC in PPSU was confirmed by Fourier transform infra-red spectroscopy (FTIR) studies by the presence of characteristic functional groups of FAC. The influence of FAC on adsorption enhanced rejection of phenol during membrane filtration has been investigated. RESULTS: The hydrophilicity of PPSU/FAC composite membranes has been improved by FAC as there was a profound reduction in contact angle from 71.8° to 43.8°. With the minimum loading of 0.25wt% of FAC in PPSU, the maximum adsorption of phenol has taken place suggesting that the better dispersion of minimal loading will offer higher accessibility to adsorptive sites. CONCLUSIONS: The adsorption of phenol on FAC was observed to be higher in PPSU/FAC composite membranes when compared with FAC being used solely as an adsorbent.

The polystyrene nanoparticles incorporating hydrophobic and fluorescent pyrene was successfully prepared by a direct polymerization at phase inversion temperature. The average diameter of the prepared polystyrene nanoparticles is around 30 nm or less: 22 nm. This preparation does not require any strong agitation, which is necessary for the usual mini-emulsion polymerization, and does not need the large amount of surfactant as much as the usual microemulsion polymerization. The incorporation of pyrene in the prepared polystyrene particles was confirmed by fluorescence spectra. This developed method is superior to the addition of pyrene to polystyrene particles prepared, which causes large coagulum and gives polystyrene particles with lower weight fraction of pyrene. The developed method is expected to be applicable for preparation of polymer particles including various hydrophobic materials. Copyright © 2014 John Wiley & Sons, Ltd.

Two types of micro-tubular hollow fiber SOFCs (MT-HF-SOFCs) were prepared using phase inversion and sintering; electrolyte-supported, based on highly asymmetric Ce0.9Gd0.1O1.95(CGO) HFs and anode-supported based on co-extruded NiO-CGO(CGO)/CGO HFs. Electroless plating was used to deposit Ni onto the inner surfaces of the electrolyte-supported MT-HF-SOFCs to form Ni-CGO anodes. LSCF-CGO cathodes were deposited on the outer surface of both these MT-HF-SOFCs before their electrochemical performances were compared at similar operating conditions. The performance of the anode-supported MT-HF-SOFCs which delivered ca. 480 mW cm–2 at 600 °C was superior to the electrolyte-supported MT-HF-SOFCs which delivered ca. six times lower power. The contribution of ohmic and electrode polarization losses of both FCs was investigated using electrochemical impedance spectroscopy. The electrolyte-supported MT-HF-SOFCs had significantly higher ohmic and electrode polarization ASR values; this has been attributed to the thicker electrolyte and the difficulties associated with forming quality anodes inside the small (

The kerosene–water flow in vertical and inclined pipes of 77.8 mm inner diameter and 4500 mm length has been investigated numerically. Simulations were carried out at three inclination angles of 0°, 5° and 30° from vertical for superficial water velocities in the range of 0.29–1.6 m/s and volumetric qualities in the range of 9.2–65.5%. Results from the simulations have been compared with the corresponding experimental data from our previous study to check the suitability of meshing, physical models and boundary conditions used. The results from CFD predictions show a reasonable agreement with the experimental data for the vertical pipe. Some discrepancies have been observed near the walls for inclined pipes as the flow becomes more complex with the appearance of drops swarms. The same computational domain was then used to investigate the effect of a higher volumetric quality and superficial water velocity on the flow characteristics. The axisymmetrical distribution of the volume fraction, water velocity and drops velocity which were observed in the vertical pipe has changed into asymmetrical distribution in the inclined pipe. It has also been observed that increasing the superficial water velocity and volumetric quality modifies the distributions of flow parameters due to the movement of kerosene drops toward the lower part of the pipe. The results from CFD predictions on the volume fraction distribution at 30° inclination indicate the appearance of phase inversion phenomenon when the volumetric quality becomes greater than 65%.

Prediction and control of membrane morphology using multi-phase thermodynamic knowledge are of growinginterest. The water/dimethylsulfoxide/polyethersulfone ternary system is a widely used casting dope for thepreparation of MF, UF, and NF membranes. In the current study, Flory–Huggins (F–H) model was applied to predictthe behavior of this ternary system during phase inversion. Titration method was applied to generate cloud pointdata. The prediction accuracy of the F–H model was directly dependent on the binary interactions of the systemcomponents. The compressible regular solution (CRS) model predicts the binodal location using only the purecomponent properties as the input parameters. Accordingly, the influence of binary parameters on the location ofthebinodalcurveswasinvestigated.Thepredictedbinodalpointsshowedsuperioraccordancewiththeexperimentaldata, where the binary interaction between nonsolvent (water) and solvent (DMSO) was overlooked. In addition,the modelling results emphasized on the pivotal importance of the interactions between polymer (PES) andnonsolvent (water) on the phase inversion and thus, on the control of the membrane morphology. The CRSmodel offered a greater conformity with the experimental results in comparison with the F–H theory. Copyright© 2013 John Wiley & Sons, Ltd.Keywords: membrane; casting solution; phase diagram; Flory–Huggins theory; binary interactions

Complete CO2/CH4 gas separation was aimed in this study. Accordingly, asymmetric neat polysulfone (PSF) and PSF/polyvinylpyrrolidone (PVP) blend membranes were prepared by wet/wet phase inversion technique. The effects of two different variables such as type of external nonsolvent and type of solvent on morphology and gas separation ability of neat PSF membranes were examined. Moreover, the influence of PVP concentration on structure, thermal properties, and gas separation properties of PSF/PVP blend membrane were tested. The SEM results presented the variation in membrane morphology in different membrane preparation conditions. Atomic forced microscopic images displayed that surface roughness parameters increased significantly in higher PVP loading and then gas separation properties of membrane improved. Thermal gravimetric analysis confirms higher thermal stability of membrane in higher PVP loading. Differential scanning calorimetric results prove miscibility and compatibility of PSF and PVP in the blend membrane. The permeation results indicate that, the CO2 permeance through prepared PSF membrane reached the maximum (275 ± 1 GPU) using 1-methyl-2-pyrrolidone as a solvent and butanol (BuOH) as an external nonsolvent. While, a higher CO2/CH4 selectivity (5.75 ± 0.1) was obtained using N-N-dimethyl-acetamide (DMAc) as a solvent and propanol (PrOH) as an external nonsolvent. The obtained results show that PSF/PVP blend membrane containing 10 wt % of PVP was able to separate CO2 from CH4 completely up to three bar as feed pressure.