In this study, we report for the first time a pioneering method to prepare membranes with a fibrous morphology via phase inversion with extremely high pore connectivity. Microfiber aligned hollow fiber membranes were prepared via a polymer blend solution consisting of poly (vinylidene fluoride) with polysulfone in PolarClean® as a green solvent. The microfiber structure appeared only when controlled phase separation was performed with polymer blends. A systematic analysis has revealed that the shear rate and the reduced capillary number (?) of a blend solution significantly affected the morphology of the final membrane. The fabricated fibrous membranes exhibited six-fold higher water productivity compared to the best electrospun membranes reported in the literature, yet they remain highly scalable.

Efficient construction of ceramic membranes can decrease the cost and ease the process of wastewater treatment. The total cost of ceramic membranes is mainly determined by the cost of raw materials and energy consumption during sintering process. In this work, fly ash particles recycled from electric plant and kaolin materials were respectively employed as the support and membrane layer of composite ceramic membranes. To match the sintering temperature of the kaolin material and fly ash support, rigid alumina particles were introduced into the supports (AFA supports). Also, the bending strength of the supports was improved when adding alumina par-ticles. The kaolin/fly ash ceramic membrane was obtained by spraying the kaolin dispersion on the AFA supports and co-sintering. The mean pore diameter and water permeance of the membranes were 320 nm and 3650 Lm

Membrane engineering, as already demonstrated in different fields, can have an interesting share in the shift towards sustainable productions. The current abundant availability of 'shale gas' requires sustainable choices and a delocalized approach that avoids underutilization or waste of methane. This scenario is highly favourable for new technologies such as the Membrane Reactors that are advanced reactors in the Process Intensification logic. Membrane Reactors can accomplish the methane conversion to ethylene, valorizing these resources. In addition, being modular and automated, they are particularly suited for dislocated/remote locations. At the same time, Membrane Reactors can exploit the potential of CO2 as feedstock through a recycle strategy. Different conversion options and the most promising membrane-based alternatives are described, proposing their integration for a sustainable ethylene production.

Membrane-assisted crystallization is a new unit operation for separation and/or promotion of pure crystals formation, where microporous hydrophobic membranes are used not as selective barriers but to pro-mote water vapor transfer between phases inducing supersaturation in solution. Polyvinylidene fluoride (PVDF) is one of the most utilized polymers due to its excellent combination of properties and processability and has been used in a wide plethora of applications in membrane technology including membrane crystallization. PVDF has different polymorphs and this property is important in membrane technology because different phases might significantly affect the final membrane properties and performances, e.g., on membrane fouling and membrane wetting. A clear correlation between the dominating crystalline phases in PVDF and the performance in mem-brane contactor applications, and in particular in membrane crystallization is still missing and necessary. In this work, molecular dynamics simulation was utilized to analyze the relationship and influence of different poly-morphs of PVDF membranes on crystals formation via membrane crystallization process. Atomistic simulations were used to study the crystal nucleation and growth of sodium chloride in contact with amorphous, ? and ? PVDF hydrophobic polymer surfaces at a supersaturated concentration of salt. Predictions about the ability of ? and ? polymorphs to influence the nucleation and growth of salts were obtained. The results specified the crys-tals (as cluster) size distributions, the size of critical nuclei, and the nucleation rate. The amorphous PVDF led to the formation of smaller but more regular clusters in reference to the other samples; ? PVDF produced much more inhomogeneous crystals and of small dimensions; ? PVDF produces crystals of larger dimensions than ? PVDF.

This chapter will focus on the use of membrane operations in the concentration of liquid foods and food ingredients in light of the recent advances and developments in this field. Specific applications of NF, RO, FO and membrane contactors as well as of integrated membrane systems are analyzed and discussed highlighting key advantages and drawbacks over conventional methodologies.

This work was aimed at investigating, for the first time, a sustainable process for the purification of biologically active compounds from goji berry (Lycium barbarum) fruit extracts. It was based on a 'green' aqueous extraction of fruits, a clarification step of the extract with microfiltration (MF) and ultrafiltration (UF) membranes and a fractionation/concentration step of the clarified extract through the use of tight UF membranes. The aqueous extraction was studied in order to obtain the maximum yield of biologically active compounds. At this purpose, different parameters such as the extraction time, temperature and solid/liquid ratio, were optimized. Three different commercial membranes with molecular weight cut-off (MWCO) from 0.5 to 3.5 kDa (GE, GH and GK from GE Osmonics) were tested in the fractionation step. The performance of selected membranes, was evaluated in terms of productivity and selectivity towards target compounds. To fulfil the final aim to purify polyphenols from carbohydrates the membrane process was also studied in a diafiltration mode. Fouling index and cleaning efficiency were analysed in order to determine process feasibility at industrial scale. Experimental results indicated that the GH membrane with a MWCO of 2.5 kDa exhibited the best separation efficiency of polyphenols from carbohydrates. For this membrane, an improved purification of polyphenols from carbohydrates by increasing the diafiltration volume, D (-), was observed: at a D (-) of 5 the removal of carbohydrates in the UF retentate was higher than 90% in comparison with the clarified extract; on the other hand, the loss of polyphenols in the permeate was lower than 20%. The investigated work allowed to obtain two distinct natural aqueous extracts from goji berries: a concentrated extract enriched in polyphenols with high antioxidant activity of interest for pharmaceutical, cosmetic or nutraceutical applications and a purified extract enriched in carbohydrates useful in the food industry.

Membrane engineering is one of the disciplines most involved in the technological innovations necessary to face the problems characterizing the world today and in future such as water shortage, raw material depletion, and energy consumption. In desalination and wastewater treatment purification and recycle, in biomedical application, in food and beverage production and in various other strategical area, integrated membrane operation have a strategic central role. In china important progresses have been achieved in industrial applications and Chinese researcher have prestigious positions in scientific community. Redesign on the mining industry introducing membrane systems in the recovery of minerals from sea and brackish water, contributions on space engineering and redesign petrochemicals new area for the growth of membrane engineering.

Membrane assisted crystallization (MCr) is a well-known technology where microporous hydrophobic membranes are used to promote the water vapor transfer between phases inducing supersaturation in solution1. Membrane crystallization is an efficient process for production, purification and/or recovery of solid materials with interesting advantages in comparison to traditional crystallization techniques, such as well-controlled nucleation and growth kinetics and fast crystallization rates and reduced induction time2. It is generally difficult to monitor the growth mechanisms of crystals formation however, molecular modelling helps to investigate the mechanism of nucleation and crystals growth3,4. Our contribution was aimed at analyzing the crystal nucleation and growth of sodium chloride in contact with hydrophobic polyvinylidene fluoride (PVDF) surfaces (amorphous together with alpha and beta phases) at a supersaturated concentration of salt. The results show that salt nucleation is faster with amorphous PVDF model then ? and ? PVDF. Molecular models confirm the highly efficient packing of the alfa and beta polymer chains, in comparison to the amorphous one resulting in greater diffusion of water molecules References 1. Drioli E., Di Profio G., Curcio E., Membrane-assisted crystallization technology (Vol. 2) (World Scientific, 2015). ISBN: 978-1-78326-333-2. 2. Macedonio F., Drioli E., Desalination and Water Treatment, 18 (1-3): 224-234, 2010. 3. D. Chakraborty et al., How crystals nucleate and grow in aqueous NaCl solution Chem. Phys. Letters, 587: 25-29, 2013. 4. Tsai J.H. et al., Membrane-Assisted Crystallization: A Molecular View of NaCl Nucleation and Growth. App. Sci. 2018, 8, 2145. Applied Sci., 8:2145-2152, 2018.

Desalination is imperative to mitigate the global water scarcity as it produces drinking water from unpotable water. Currently, reverse osmosis membrane processes are widely used and account for 60% of desalination plants globally as they have lower energy requirements than other techniques, such as thermal desalination. Another promising alternative to desalination is membrane distillation (MD), which has been highlighted as one of the most promising and cost-effective desalination technologies over the last five decades. MD is a thermally driven desalination process that uses microporous and hydrophobic membranes through which only vapor can pass. Because non-volatile ions cannot pass through the membrane, MD theoretically achieves 100% salt rejection. In addition, MD is superior to other techniques as it is conducted at relatively low temperature and pressure, and is less sensitive to the feed concentration. MD is a desalination process that uses the vapor pressure difference between the feed and permeate as the driving force through the membranes

Membrane assisted condenser is an innovative membrane operations that exploits the hydrophobic nature of microporous membranes to promote water vapor condensation and recovery[1,2,3]. [...]

[object Object]{"p":"Poly(vinylidene fluoride)(PVDF)is a kind of hydrophobic polymer with excellent thermal stability,processability and chemical resistance.Membrane condenser has been introduced as membrane process recently,and the hydrophobic membrane plays an important role in the separation of two phase and heat conduction in the membrane condenser.PVDF membranes can be used for membrane condenser due to its hydrophobicity. However,the water recovery rate of PVDF membrane in membrane condensation is not high due to the low thermal conductivity of PVDF.In order to achieve the purpose of enhancing the thermal conductivity of the PVDF membrane,the short multi-wall carbon nanotubes (SMWCNTs)with high thermal conductivity was doped in PVDF casting solutions to prepare the PVDF membrane.When the SMWCNTs concentration was 0.2%,the hydrophobicity and mechanical properties of the PVDF membrane had been significantly improved with little change in the properties of the original membrane,and the thermal conductivity of the PVDF membrane had also increased from 0.068 6W/(m· K)to 0.077 1W/(m·K).Water recovery and the flow rates in membrane condensation reached 17.39% and 0.85kg/(m~2·h),which greatly improved the efficiency of the membrane condensation process."}

The removal of particulate matter from the gaseous streams emitted from industrial plants has become one of the most relevant environmental issues because of its hazardous effects on human health. In this work, we propose the use of membrane condenser as a pre-treatment unit for the retention of particles contained in waste gaseous streams. We calculated the retention efficiency of membrane condenser on the basis of the aerosol technology and we analysed the various contributions related to interception, impaction, diffusion, and gravitation. The variation of the retention efficiency was analysed considering a particle diameter ranging from 0.1 to 10 ?m, at various density of the particle itself. In addition, the effect of the membrane properties such as thickness, pore diameter, permeating flux velocity as well as of the temperature of the gaseous stream to be treated was investigated. The gas velocity resulted a determining variable in the retention efficiency, specifically for particles with a diameter lower than 1 ?m, showing 10-50% variation for a particle diameter of 0.3 ?m. The same drop was observed when the membrane pore diameter passed from 0.2 to 3 ?m, confirming the significant importance of having membranes with a narrow pore distribution.

The present work has undertaken a meticulous glance on optimizing the performance of an SGMD configuration utilized a porous poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) membrane. This was carried out by conducting a systematic framework for investigating and optimizing the pertinent parameters such as sweeping gas flow rate, feed temperature, feed concentration and feed flow rate on the permeate flux. For this purpose, the Taguchi method and design of experiment techniques were harnessed to statistically determine optimum operational conditions. Besides that, a comprehensive surface and permeation characterization was conducted against the hand-made membranes. Results showcased that the membrane performance was ultimately controlled by the feed temperature and was nearly (~680) % higher when the temperature raised from 45 to 65C. Also, to a lesser extent, the system was dominated by the feed flow rate. As the adopted feed flow rate increases (from 0.2 to 0.6 L/min), around 47.5% increment was bestowed on water permeability characteristics. In contra, 34.5% flux decline was witnessed when higher saline feed concentration (100 g/L) was utilized. In the meantime, with raising the sweeping gas flow rate (from 120 to 300 L/h), the distillate was nearly 129% higher. Based on Taguchi design, the maximum permeate flux (17.3 and 17 kg/m was secured at 35 g/L, 0.4 L/min, 65C and 300 L/h, for both commercial and prepared membranes, respectively.

Research activities on the application of direct contact membrane distillation (DCMD) for processing at low temperature (up to 50C) solutions containing urea were presented and discussed. Feeds were urine (also in mixture) and human plasma ultrafiltrate. Moreover, as a case study, the performance of membrane modules of different sizes and features was investigated for reaching the productivities needed in the treatment of the human plasma ultrafiltrate. In particular, two modules were equipped with the same type of capillaries, but differed in terms of membrane area, while the third module contained a different type of membranes and presented a membrane area in between those of the two previous modules. The three modules were compared, at a parity of operating temperatures and streams velocity, in terms of transmembrane flux, permeate production and size, underlining the directions to follow for a real implementation of the technique.

In this work, date juices were concentrated at low temperature by Vacuum Membrane Distillation (VMD). Tests were conducted at fixed operating conditions (feed flowrate, 28 L/h; feed temperature, 28 °C; vacuum pressure, 4 mbar) on two commercial flat polypropylene membranes, different in pore size and thickness. Date concentrates (70 °Bx) were obtained starting from juices at 18 °Bx, and pure permeates (0 °Bx) were collected. The water vapour trans-membrane flux depended on membrane properties until a concentration of ~50 °Bx was reached; then, the resistance at the feed side controlled the process.

Membrane distillation is envisaged to be a promising best practice to recover freshwater from seawater withthe prospect of building low energy-consuming devices powered by natural and renewable energy sourcesin remote and less accessible areas. Moreover, there is an additional benefit of integrating this greentechnology with other well-established operations dedicated to desalination. Today, the development ofmembrane distillation depends on the productivity-efficiency ratio on a large scale. Despite hydrophobiccommercial membranes being widely used, no membrane with suitable morphological and chemicalfeature is readily available in the market. Thus, there is a real need to identify best practices fordeveloping new efficient membranes for more productive and eco-sustainable membrane distillationdevices. Here, we propose engineered few-layer graphene membranes, showing enhancedtrans-membranefluxes and total barrier action against NaCl ions. The obtained performances are linked withfilling polymeric membranes with few-layer graphene of 490 nm in lateral size, produced by the wet-jetmilling technology. The experimental evidence, together with comparative analyses, confirmed that theuse of more largely sized few-layer graphene leads to superior productivity related efficiency trade-offfor the membrane distillation process. Herein, it was demonstrated that the quality of exfoliation isa crucial factor for addressing the few-layer graphene supporting the separation capability of the hostmembranes designed for water desalination