Segui questo link per vedere altri tipi di pubblicazioni sul tema: Membrane separation.
Articoli di riviste sul tema "Membrane separation"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Vedi i top-50 articoli di riviste per l'attività di ricerca sul tema "Membrane separation".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Vedi gli articoli di riviste di molte aree scientifiche e compila una bibliografia corretta.
1
Saha, S. N. "Membrane Separations". Current Research in Agriculture and Farming 3, n. 6 (30 dicembre 2022): 19–33. http://dx.doi.org/10.18782/2582-7146.180.
Testo completoAbstract (sommario):
Membrane technology is widely utilised in industries for separation, concentration, filtering, and extraction operations. Membrane technology carries out various applications by utilising simple and specially designed semi-permeable membranes. It uses little energy and is thus considered a green technology. Ultrafiltration (UF), Microfiltration (MF), Nano-filtration (NF), and Reverse osmosis (RO) are membrane filtration methods that have a major influence on the organoleptic and nutritional qualities of juice. The adoption of a membrane method linked with enzymatic hydrolysis resulted in clarified and concentrated fruit juices with good sensory and nutritional quality. Membrane fouling is a significant problem of membrane-based separation processes. Membrane procedures powered by pressure, such as MF, UF, NF, and RO, allow for the separation of components with a wide variety of particle sizes. Because of this, they have a wide range of uses in the food processing business.
2
Burganos, Vasilis N. "Membranes and Membrane Processes". MRS Bulletin 24, n. 3 (marzo 1999): 19–22. http://dx.doi.org/10.1557/s0883769400051861.
Testo completoAbstract (sommario):
Membrane separation science has enjoyed tremendous progress since the first synthesis of membranes almost 40 years ago, which was driven by strong technological needs and commercial expectations. As a result, the range of successful applications of membranes and membrane processes is continuously broadening. An additional change lies in the nature of membranes, which is now extended to include liquid and gaseous materials, biological or synthetic. Membranes are understood to be thin barriers between two phases through which transport can take place under the action of a driving force, typically a pressure difference and generally a chemical or electrical potential difference.An attempt at functional classification of membranes would have to include diverse categories such as gas separation, pervaporation, reverse osmosis, micro- and ultrafiltration, and biomedical separations. The dominant application of membranes is certainly the separation of mixed phases or fluids, homogeneous or heterogeneous. Separation of a mixture can be achieved if the difference in the transport coefficients of the components of interest is sufficiently large. Membranes can also be used in applications other than separation targeting: They can be employed in catalytic reactors, energy storage and conversion systems, as key components of artificial organs, as supports for electrodes, or even to control the rate of release of both useful and dangerous species.In order to meet the requirements posed by the aforementioned applications, membranes must combine several structural and functional properties.
3
Liu, Congmin, Xin Zhang, Junxiang Zhai, Xuan Li, Xiuying Guo e Guangli He. "Research progress and prospects on hydrogen separation membranes". Clean Energy 7, n. 1 (1 febbraio 2023): 217–41. http://dx.doi.org/10.1093/ce/zkad014.
Testo completoAbstract (sommario):
Abstract Membrane separation technologies, with a broad application prospect in the field of hydrogen separation, are characterized by the simplicity of the devices, high energy efficiency and environmental friendliness. The performance of separation membranes is the primary factor that determines the efficiency of hydrogen separation. Therefore, the development of hydrogen separation membranes is always a research focus. This paper presents and reviews the research developments and features of organic membranes, inorganic membranes and hybrid matrix membranes for hydrogen separations. First, the characterization methods of key index parameters of membrane materials are presented. Second, the performance parameters of different types of membrane are compared. Finally, the trend of technological development of different types of membrane materials is forecast.
4
Li, Xue, Jun Pan, Francesca Macedonio, Claudia Ursino, Mauro Carraro, Marcella Bonchio, Enrico Drioli, Alberto Figoli, Zhaohui Wang e Zhaoliang Cui. "Fluoropolymer Membranes for Membrane Distillation and Membrane Crystallization". Polymers 14, n. 24 (12 dicembre 2022): 5439. http://dx.doi.org/10.3390/polym14245439.
Testo completoAbstract (sommario):
Fluoropolymer membranes are applied in membrane operations such as membrane distillation and membrane crystallization where hydrophobic porous membranes act as a physical barrier separating two phases. Due to their hydrophobic nature, only gaseous molecules are allowed to pass through the membrane and are collected on the permeate side, while the aqueous solution cannot penetrate. However, these two processes suffer problems such as membrane wetting, fouling or scaling. Membrane wetting is a common and undesired phenomenon, which is caused by the loss of hydrophobicity of the porous membrane employed. This greatly affects the mass transfer efficiency and separation efficiency. Simultaneously, membrane fouling occurs, along with membrane wetting and scaling, which greatly reduces the lifespan of the membranes. Therefore, strategies to improve the hydrophobicity of membranes have been widely investigated by researchers. In this direction, hydrophobic fluoropolymer membrane materials are employed more and more for membrane distillation and membrane crystallization thanks to their high chemical and thermal resistance. This paper summarizes different preparation methods of these fluoropolymer membrane, such as non-solvent-induced phase separation (NIPS), thermally-induced phase separation (TIPS), vapor-induced phase separation (VIPS), etc. Hydrophobic modification methods, including surface coating, surface grafting and blending, etc., are also introduced. Moreover, the research advances on the application of less toxic solvents for preparing these membranes are herein reviewed. This review aims to provide guidance to researchers for their future membrane development in membrane distillation and membrane crystallization, using fluoropolymer materials.
5
A.A. Kittur. "MFI Zeolite Membranes and PV Separation of Isopropanol-Water Azeotropic Mixtures". International Research Journal on Advanced Engineering and Management (IRJAEM) 2, n. 03 (16 marzo 2024): 299–306. http://dx.doi.org/10.47392/irjaem.2024.0044.
Testo completoAbstract (sommario):
Membrane separation process has become one of the emerging technologies that undergo a rapid growth since few decades. Pervaporation (PV) is one among the membrane separation processes which gained foremost interest in the chemical and allied industries. It is an effective and energy-efficient technology that carries out separations, which are difficult to achieve by conventional separation processes. Inorganic membranes such as zeolite membranes with uniform, molecular-sized pores, selective adsorption and molecular sieving action offer unique type of pervaporation membrane for a number of separation processes. This paper presents the role of MFI-zeolite membrane and its progress in the pervaporation process. The fundamental aspects of pervaporation over different types of membranes are reviewed and compared. The focus of this paper is on zeolite membrane synthesis, membrane characterization and pervaporation studies. The transport mechanism during pervaporation is discussed and the issues related with pervaporation are addressed. Innovation and future development of zeolite membrane in pervaporation are also presented.
6
Raza, Ayesha, Sarah Farrukh, Arshad Hussain, Imranullah Khan, Mohd Hafiz Dzarfan Othman e Muhammad Ahsan. "Performance Analysis of Blended Membranes of Cellulose Acetate with Variable Degree of Acetylation for CO2/CH4 Separation". Membranes 11, n. 4 (29 marzo 2021): 245. http://dx.doi.org/10.3390/membranes11040245.
Testo completoAbstract (sommario):
The separation and capture of CO2 have become an urgent and important agenda because of the CO2-induced global warming and the requirement of industrial products. Membrane-based technologies have proven to be a promising alternative for CO2 separations. To make the gas-separation membrane process more competitive, productive membrane with high gas permeability and high selectivity is crucial. Herein, we developed new cellulose triacetate (CTA) and cellulose diacetate (CDA) blended membranes for CO2 separations. The CTA and CDA blends were chosen because they have similar chemical structures, good separation performance, and its economical and green nature. The best position in Robeson’s upper bound curve at 5 bar was obtained with the membrane containing 80 wt.% CTA and 20 wt.% CDA, which shows the CO2 permeability of 17.32 barrer and CO2/CH4 selectivity of 18.55. The membrane exhibits 98% enhancement in CO2/CH4 selectivity compared to neat membrane with only a slight reduction in CO2 permeability. The optimal membrane displays a plasticization pressure of 10.48 bar. The newly developed blended membranes show great potential for CO2 separations in the natural gas industry.
7
Ma, Xiaoli, e Defei Liu. "Zeolitic Imidazolate Framework Membranes for Light Olefin/Paraffin Separation". Crystals 9, n. 1 (25 dicembre 2018): 14. http://dx.doi.org/10.3390/cryst9010014.
Testo completoAbstract (sommario):
Propylene/propane and ethylene/ethane separations are performed by energy-intensive distillation processes, and membrane separation may provide substantial energy and capital cost savings. Zeolitic imidazolate frameworks (ZIFs) have emerged as promising membrane materials for olefin/paraffin separation due to their tunable pore size and chemistry property, and excellent chemical and thermal stability. In this review, we summarize the recent advances on ZIF membranes for propylene/propane and ethylene/ethane separations. Membrane fabrication methods such as in situ crystallization, seeded growth, counter-diffusion synthesis, interfacial microfluidic processing, vapor-phase and current-driven synthesis are presented. The gas permeation and separation characteristics and membrane stability are also discussed.
8
Mondal, Arijit, e Chiranjib Bhattacharjee. "Membrane Transport for Gas Separation". Diffusion Foundations 23 (agosto 2019): 138–50. http://dx.doi.org/10.4028/www.scientific.net/df.23.138.
Testo completoAbstract (sommario):
Gas separations through organic membranes have been investigated from last several years and presently it has been accepted for commercial applications. This chapter will focus on membrane based gas separation mechanism as well as its application. This chapter will cover ‘‘diffusivity controlled’’ and ‘‘solubility controlled’’ mechanism and choice of suitable polymers for different gas phase applications like acidic gas, C3+ hydrocarbon, nitrogen, water vapor and helium. Diffusivity controlled mechanism performs on free volume elements of the glassy polymers via hindrance of chain packing by functional groups and restricted by the permselectivity. Other mechanism performs on the basis of molecular structure with affinity towards the target molecule and follows enhanced solution-diffusion rout. Commercially available organic membrane materials for Carbon dioxide (CO2) removal are discussed along with process design. Membranes based separation process for heavy hydrocarbon recovery, nitrogen separation, helium separation and dehydration are less developed. This article will help us to focus on the future direction of those applications based on membrane technology. Keywords: Membrane, C3+ hydrocarbon, Diffusivity controlled, Solubility controlled, Selectivity, Permeability. *Corresponding author: E-mail address: c.bhatta@gmail.com (Chiranjib Bhattacharjee), Tel.: +91-9836402118.
9
Yuan, Cui, Qi, Wei e Qaisrani. "Experimental Investigation of Copper Mesh Substrate with Selective Wettability to Separate Oil/Water Mixture". Energies 12, n. 23 (29 novembre 2019): 4564. http://dx.doi.org/10.3390/en12234564.
Testo completoAbstract (sommario):
To solve the problem of low efficiency and poor adaptability during complex oil/water mixtures separation, two types of membranes with superhydrophilicity/underwater-superoleophobicity were successfully fabricated by oxidative reaction and in situ displacement reaction methods. A nanoneedle Cu(OH)2 structure was generated on the copper mesh substrate by oxidative reaction and feathery micro/nanoscale composite, while Ag structure was constructed at the surface of copper mesh substrate through in-situ replacement, then, membranes with superhydrophilic/underwater-superoleophobic properties were separated. The influence of microstructure, wettability of the surface of prepared membranes and the liquid constituents in the separation experiment were studied and the liquid flux and permeation pressure at the membrane were later experimentally investigated. The experimental results show that separation efficiency of both membranes for separating different oil/water mixtures was above 99.8%. However, the separation efficiency of the Ag-CS (Ag on the copper substrate) membrane was obviously higher than that of the Cu(OH)2-CS (Cu(OH)2 on the copper substrate) membrane after 10 instances of separation because of the micro/nanocomposite structures. By comparison, it was found that the Ag-CS membrane showed a relatively higher permeation pressure but lower liquid flux as compared to Cu(OH)2-CS membrane, due to the influence of microscale structure and the wettability of the surface combined. In addition, the outcome for separating the multicomponent oil/water mixture illustrate that the result of TOC (the Total Organic Carbon) test for the Cu(OH)2-CS membrane and Ag-CS membrane were 31.2% and 17.7%, respectively, higher than the average of the two oils probably because some oil droplets created due to mutual dissolution passed through the membranes. However, these two fabricated membranes still retained higher separation efficiencies and good adaptability after 10 instances of separation. It was concluded that based on the good performances of the prepared membranes, especially the modified membrane, they have a vast application prospect and can be widely used.
10
Talukder, Md Eman, Fariya Alam, Mst Monira Rahman Mishu, Md Nahid Pervez, Hongchen Song, Francesca Russo, Francesco Galiano, George K. Stylios, Alberto Figoli e Vincenzo Naddeo. "Sustainable Membrane Technologies for by-Product Separation of Non-Pharmaceutical Common Compounds". Water 14, n. 24 (13 dicembre 2022): 4072. http://dx.doi.org/10.3390/w14244072.
Testo completoAbstract (sommario):
The Chinese pharmaceutical industry and traditional Chinese medicine (TCM) are both vital components of Chinese culture. Some traditional methods used to prepare TCMs have lost their conformity, and as a result, are producing lower-quality medicines. In this regard, the TCM sector has been looking for new ways to boost productivity and product quality. Membrane technology is environmentally-friendly, energy-saving technology, and more efficient than traditional technologies. Membrane separation is the most effective method for separating and cleaning the ingredients of the non-pharmaceutical common compounds from traditional Chinese medicine (TCM). Membrane technology is currently being employed for the concentration, purification, and separation of TCMs. This review paper discusses how membranes are fabricated and their role in non-pharmaceutical common compound separation and TCM purification. Accordingly, the membrane applicability and the technological advantage were also analyzed in non-pharmaceutical common compound separation. Researchers pay attention to the choice of membrane pore size when selecting membranes but often ignore the influence of membrane materials and membrane structure on separation, resulting in certain blindness in the membrane selection process.
11
Bera, Debaditya, Rimpa Chatterjee e Susanta Banerjee. "Aromatic polyamide nonporous membranes for gas separation application". e-Polymers 21, n. 1 (1 gennaio 2021): 108–30. http://dx.doi.org/10.1515/epoly-2021-0016.
Testo completoAbstract (sommario):
Abstract Polymer membrane-based gas separation is a superior economical and energy-efficient separation technique over other conventional separation methods. Over the years, different classes of polymers are investigated for their membrane-based applications. The need to search for new polymers for membrane-based applications has been a continuous research challenge. Aromatic polyamides (PAs), a type of high-performance materials, are known for their high thermal and mechanical stability and excellent film-forming ability. However, their insolubility and processing difficulty impede their growth in membrane-based applications. In this review, we will focus on the PAs that are investigated for membrane-based gas separations applications. We will also address the polymer design principal and its effects on the polymer solubility and its gas separation properties. Accordingly, some of the aromatic PAs developed in the authors’ laboratory that showed significant improvement in the gas separation efficiency and placed them in the 2008 Robeson upper bound are also included in this review. This review will serve as a guide to the future design of PA membranes for gas separations.
12
Gao, Lin, Huaiyou Wang, Yue Zhang e Min Wang. "Nanofiltration Membrane Characterization and Application: Extracting Lithium in Lepidolite Leaching Solution". Membranes 10, n. 8 (3 agosto 2020): 178. http://dx.doi.org/10.3390/membranes10080178.
Testo completoAbstract (sommario):
This study concerns the feasibility of extracting lithium and separating aluminum from lepidolite leaching solution by nanofiltration. Four commercial nanofiltration (NF) membranes (DK, DL, NF270, and Duracid NF) were chosen to investigate ion separation performance in simulated lepidolite leaching solution. Membranes were characterized according to FT-IR, hydrophobicity, zeta potential, morphology, thickness, pore size, and hydraulic permeability to reveal the effect of membrane properties on separation. NF membranes were investigated including the retention ratio of SO42− and Li+, the separation efficiency of Li+/Al3+, and the effect of other cations (K+, Na+, Ca2+) on the separation of Li+/Al3+. The results show that DK membrane displayed the appropriate permeate flux and extremely high Li+/Al3+ separation efficiency with a separation factor of 471.3 compared with other NF membranes owing to its pore size, smooth membrane surface, and appropriate zeta potential. Overall, it is found that nanofiltration has a superior separation efficiency of lithium and aluminum, which may bring deep insights and open an avenue to offer a feasible strategy to extract lithium from lepidolite leaching solution in the future.
13
Ma, Yi Hua. "Dense Palladium and Perovskite Membranes and Membrane Reactors". MRS Bulletin 24, n. 3 (marzo 1999): 46–49. http://dx.doi.org/10.1557/s0883769400051915.
Testo completoAbstract (sommario):
The development of high-temperature processes and tighter environmental regulations requires utilization of efficient gas-separation processes that will provide high fluxes, high selectivity of separation, and the ability to operate at elevated temperatures. Dense inorganic membranes and membrane reactors are especially well suited for high-temperature reactions and separations, due in part to their thermal stability and high separation selectivity (in theory, infinite). Furthermore, membrane reactors offer an inherent advantage of combining reaction, product concentration, and separation in a single-unit operation for the improvement of process economics and waste minimization.The classification of membrane reactors can either be by membrane material and geometry or by the configuration of the reactor. Porous and dense membranes in both tubular and disk forms have been used for membrane reactors. The membrane can either be catalytically active (catalytic membrane reactor [CMR]) or simply act as a separation medium. In the latter case, the catalyst is packed in the reactor, whose walls are formed by the membrane (packed-bed membrane reactor [PBMR]). In addition, if the membrane is also catalytically active, the reactor is called a packed-bed catalytic membrane reactor (PBCMR).The principal materials from which porous inorganic (ceramic) membranes are made are alumina, zirconia, and glass. Alumina and zirconia membranes are usually asymmetric and composite, with a porous support (0.5–2.0 mm thick) for mechanical strength and one or more thin layers for carrying out separations.On the other hand, glass membranes, such as Vycor and microporous glass, have symmetric pores. Materials commonly used as the porous support are alumina, granular carbon, sintered metal, and silicon carbide.
14
Zhang, Li Qing, e Gang Zhang. "Influence of Membrane Structure and Chemical Characteristics on Separation and Fouling of Nanofiltration Membranes". Advanced Materials Research 864-867 (dicembre 2013): 394–98. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.394.
Testo completoAbstract (sommario):
Nanofiltration membranes act an important role in the advanced water treatment as well as waste water reclamation and other industrial separations. Therefore, an understanding of the factors affecting NF separation and membrane fouling in high-pressure membrane systems is needed. Recent studies have shown that membrane surface morphology and structure as well as surface chemical characteristics influence permeability, rejection, and fouling behavior of nanofiltration (NF) membranes. A comprehensive literature review is reported, targeting the physical-chemical characteristics of NF membrane affecting separation and fouling, including pore size, porosity, surface morphology (measured as roughness), surface charge, and hydrophobicity/ hydrophilicity.
15
Tanaka, Shunsuke, Kojiro Fuku, Naoki Ikenaga, Maha Sharaf e Keizo Nakagawa. "Recent Progress and Challenges in the Field of Metal–Organic Framework-Based Membranes for Gas Separation". Compounds 4, n. 1 (2 febbraio 2024): 141–71. http://dx.doi.org/10.3390/compounds4010007.
Testo completoAbstract (sommario):
Metal–organic frameworks (MOFs) represent the largest class of materials among crystalline porous materials ever developed, and have attracted attention as core materials for separation technology. Their extremely uniform pore aperture and nearly unlimited structural and chemical characteristics have attracted great interest and promise for applying MOFs to adsorptive and membrane-based separations. This paper reviews the recent research into and development of MOF membranes for gas separation. Strategies for polycrystalline membranes and mixed-matrix membranes are discussed, with a focus on separation systems involving hydrocarbon separation, CO2 capture, and H2 purification. Challenges to and opportunities for the industrial deployment of MOF membranes are also discussed, providing guidance for the design and fabrication of future high-performance membranes. The contributions of the underlying mechanism to separation performance and adopted strategies and membrane-processing technologies for breaking the selectivity/permeability trade-off are discussed.
16
Suraya, Tiyastiti, Ramadhan Cendy Mega Pratiwi e Adhitasari Suratman. "Effect of Ethylene Glycol on Gas Permeability and Selectivity of CH<sub>4</sub>/CO<sub>2</sub> Gas Separation in Zeolite/Alginate Membrane". Key Engineering Materials 927 (29 luglio 2022): 131–37. http://dx.doi.org/10.4028/p-c46tw5.
Testo completoAbstract (sommario):
Zeolite have been widely used as gas separation material with its promising properties. One of gas separation technology available is using membrane composites because of its various benefits. A synthesis of membrane composites consists of zeolite/alginate then caried out to study the effect of the addition of Ethylene Glycol (EG) to the CH4/CO2 selectivity performance of the membrane. Membrane synthesis varied by its mass ratio of alginate:EG for 1:0, 1:0.25, 1:0.5, 1:1, and 1:2 and evaporated in the room temperature for 72 h. Characterization of the physico/chemical properties was done with various instruments such as FT-IR (Fourier Transform Infra-Red) Spectroscopy, Texture Analyzer, SEM (Scanning Electron Microscopy), and Permeation Test Cell Unit. Addition of EG into the membrane compositions proven to improve the separation performance showed by permeation rate improvement and selectivity value. Gas selectivity separations of CH4/CO2 was also investigated and it can be concluded that the synthesized membranes have several promising properties to be used as CH4/CO2 separations membranes.
17
Thompson, J. E., C. D. Froese, Y. Hong, K. A. Hudak e M. D. Smith. "Membrane deterioration during senescence". Canadian Journal of Botany 75, n. 6 (1 giugno 1997): 867–79. http://dx.doi.org/10.1139/b97-096.
Testo completoAbstract (sommario):
The lipid bilayers of plant membranes are normally liquid crystalline, reflecting the inherent rotational motion of membrane fatty acids at physiological temperature. With the onset of senescence, the chemical composition of membrane lipids changes resulting in lipid phase separations within the bilayer. These phase changes render the membranes leaky and lead to loss of essential ion gradients and impairment of cell function. The separation of lipid phases appears to be attributable to an accumulation of lipid metabolites in the bilayer that are formed during turnover and metabolism of membrane lipids. These metabolites are normally released from membranes as lipid–protein particles found in the cell cytosol and within organelles. The lipid–protein particles also contain catabolites of membrane proteins and appear to serve as a vehicle for removing lipid and protein metabolites that would otherwise destabilize the bilayer. They bear structural resemblance to oil bodies, which are abundant in oil seeds, and have been found in leaves, cotyledons, and petals as well as in insect and animal tissue. The accumulation of lipid metabolites in senescing membranes and ensuing separation of lipid phases appear to reflect impairment of lipid–protein particle release from membranes as tissues age and to be a seminal cause of membrane dysfunction with advancing senescence. Key words: lipid bilayer, lipid phase separation, lipid–protein particles, membrane, oil body, senescence.
18
Kausar, Ayesha, e Ishaq Ahmad. "Graphene in gas separation membranes—State-of-the-art and potential spoors". Characterization and Application of Nanomaterials 7, n. 1 (9 aprile 2024): 4581. http://dx.doi.org/10.24294/can.v7i1.4581.
Testo completoAbstract (sommario):
Graphene and derivatives have been frequently used to form advanced nanocomposites. A very significant utilization of polymer/graphene nanocomposite was found in the membrane sector. The up-to-date overview essentially highpoints the design, features, and advanced functions of graphene nanocomposite membranes towards gas separations. In this concern, pristine thin layer graphene as well as graphene nanocomposites with poly(dimethyl siloxane), polysulfone, poly(methyl methacrylate), polyimide, and other matrices have been perceived as gas separation membranes. In these membranes, the graphene dispersion and interaction with polymers through applying the appropriate processing techniques have led to optimum porosity, pore sizes, and pore distribution, i.e., suitable for selective separation of gaseous molecules. Consequently, the graphene derived nanocomposites brought about numerous revolutions in high performance gas separation membranes. The structural diversity of polymer/graphene nanocomposites has facilitated the membrane selective separation, permeation, and barrier processes especially in the separation of desired gaseous molecules, ions, and contaminants. Future research on the innovative nanoporous graphene-based membrane can overcome design/performance related challenging factors for technical utilizations.
19
Jiang, Zhongyi, Liangyin Chu, Xuemei Wu, Zhi Wang, Xiaobin Jiang, Xiaojie Ju, Xuehua Ruan e Gaohong He. "Membrane-based separation technologies: from polymeric materials to novel process: an outlook from China". Reviews in Chemical Engineering 36, n. 1 (18 dicembre 2019): 67–105. http://dx.doi.org/10.1515/revce-2017-0066.
Testo completoAbstract (sommario):
Abstract During the past two decades, research on membrane and membrane-based separation process has developed rapidly in water treatment, gas separation, biomedicine, biotechnology, chemical manufacturing and separation process integration. In China, remarkable progresses on membrane preparation, process development and industrial application have been made with the burgeoning of the domestic economy. This review highlights the recent development of advanced membranes in China, such as smart membranes for molecular-recognizable separation, ion exchange membrane for chemical productions, antifouling membrane for liquid separation, high-performance gas separation membranes and the high-efficiency hybrid membrane separation process design, etc. Additionally, the applications of advanced membranes, relevant devices and process design strategy in chemical engineering related fields are discussed in detail. Finally, perspectives on the future research directions, key challenges and issues in membrane separation are concluded.
20
Zhang, Hongli, Yiling Zheng, Shuwen Yu, Weixing Chen e Jie Yang. "A Review of Advancing Two-Dimensional Material Membranes for Ultrafast and Highly Selective Liquid Separation". Nanomaterials 12, n. 12 (18 giugno 2022): 2103. http://dx.doi.org/10.3390/nano12122103.
Testo completoAbstract (sommario):
Membrane-based nanotechnology possesses high separation efficiency, low economic and energy consumption, continuous operation modes and environmental benefits, and has been utilized in various separation fields. Two-dimensional nanomaterials (2DNMs) with unique atomic thickness have rapidly emerged as ideal building blocks to develop high-performance separation membranes. By rationally tailoring and precisely controlling the nanochannels and/or nanoporous apertures of 2DNMs, 2DNM-based membranes are capable of exhibiting unprecedentedly high permeation and selectivity properties. In this review, the latest breakthroughs in using 2DNM-based membranes as nanosheets and laminar membranes are summarized, including their fabrication, structure design, transport behavior, separation mechanisms, and applications in liquid separations. Examples of advanced 2D material (graphene family, 2D TMDs, MXenes, metal–organic frameworks, and covalent organic framework nanosheets) membrane designs with remarkably perm-selective properties are highlighted. Additionally, the development of strategies used to functionalize membranes with 2DNMs are discussed. Finally, current technical challenges and emerging research directions of advancing 2DNM membranes for liquid separation are shared.
21
Astorino, Carmela, Eugenio De Nardo, Stefania Lettieri, Giuseppe Ferraro, Candido Fabrizio Pirri e Sergio Bocchini. "Advancements in Gas Separation for Energy Applications: Exploring the Potential of Polymer Membranes with Intrinsic Microporosity (PIM)". Membranes 13, n. 12 (6 dicembre 2023): 903. http://dx.doi.org/10.3390/membranes13120903.
Testo completoAbstract (sommario):
Membrane-based Polymers of Intrinsic Microporosity (PIMs) are promising candidates for energy-efficient industrial gas separations, especially for the separation of carbon dioxide over methane (CO2/CH4) and carbon dioxide over nitrogen (CO2/N2) for natural gas/biogas upgrading and carbon capture from flue gases, respectively. Compared to other separation techniques, membrane separations offer potential energy and cost savings. Ultra-permeable PIM-based polymers are currently leading the trade-off between permeability and selectivity for gas separations, particularly in CO2/CH4 and CO2/N2. These membranes show a significant improvement in performance and fall within a linear correlation on benchmark Robeson plots, which are parallel to, but significantly above, the CO2/CH4 and CO2/N2 Robeson upper bounds. This improvement is expected to enhance the credibility of polymer membranes for CO2 separations and stimulate further research in polymer science and applied engineering to develop membrane systems for these CO2 separations, which are critical to energy and environmental sustainability. This review aims to highlight the state-of-the-art strategies employed to enhance gas separation performances in PIM-based membranes while also mitigating aging effects. These strategies include chemical post-modification, crosslinking, UV and thermal treatment of PIM, as well as the incorporation of nanofillers in the polymeric matrix.
22
Zhu, Xiaoying, e Renbi Bai. "Separation of Biologically Active Compounds by Membrane Operations". Current Pharmaceutical Design 23, n. 2 (13 febbraio 2017): 218–30. http://dx.doi.org/10.2174/1381612822666161027153823.
Testo completoAbstract (sommario):
Background: Bioactive compounds from various natural sources have been attracting more and more attention, owing to their broad diversity of functionalities and availabilities. However, many of the bioactive compounds often exist at an extremely low concentration in a mixture so that massive harvesting is needed to obtain sufficient amounts for their practical usage. Thus, effective fractionation or separation technologies are essential for the screening and production of the bioactive compound products. The applicatons of conventional processes such as extraction, distillation and lyophilisation, etc. may be tedious, have high energy consumption or cause denature or degradation of the bioactive compounds. Membrane separation processes operate at ambient temperature, without the need for heating and therefore with less energy consumption. The “cold” separation technology also prevents the possible degradation of the bioactive compounds. The separation process is mainly physical and both fractions (permeate and retentate) of the membrane processes may be recovered. Thus, using membrane separation technology is a promising approach to concentrate and separate bioactive compounds. Methods: A comprehensive survey of membrane operations used for the separation of bioactive compounds is conducted. The available and established membrane separation processes are introduced and reviewed. Results: The most frequently used membrane processes are the pressure driven ones, including microfiltration (MF), ultrafiltration (UF) and nanofiltration (NF). They are applied either individually as a single sieve or in combination as an integrated membrane array to meet the different requirements in the separation of bioactive compounds. Other new membrane processes with multiple functions have also been developed and employed for the separation or fractionation of bioactive compounds. The hybrid electrodialysis (ED)-UF membrane process, for example has been used to provide a solution for the separation of biomolecules with similar molecular weights but different surface electrical properties. In contrast, the affinity membrane technology is shown to have the advantages of increasing the separation efficiency at low operational pressures through selectively adsorbing bioactive compounds during the filtration process. Conclusion: Individual membranes or membrane arrays are effectively used to separate bioactive compounds or achieve multiple fractionation of them with different molecule weights or sizes. Pressure driven membrane processes are highly efficient and widely used. Membrane fouling, especially irreversible organic and biological fouling, is the inevitable problem. Multifunctional membranes and affinity membranes provide the possibility of effectively separating bioactive compounds that are similar in sizes but different in other physical and chemical properties. Surface modification methods are of great potential to increase membrane separation efficiency as well as reduce the problem of membrane fouling. Developing membranes and optimizing the operational parameters specifically for the applications of separation of various bioactive compounds should be taken as an important part of ongoing or future membrane research in this field.
23
Avornyo, Amos, Arumugham Thanigaivelan, Rambabu Krishnamoorthy, Shadi W. Hassan e Fawzi Banat. "Ag-CuO-Decorated Ceramic Membranes for Effective Treatment of Oily Wastewater". Membranes 13, n. 2 (1 febbraio 2023): 176. http://dx.doi.org/10.3390/membranes13020176.
Testo completoAbstract (sommario):
Although ultrafiltration is a reliable method for separating oily wastewater, the process is limited by problems of low flux and membrane fouling. In this study, for the first time, commercial TiO2/ZrO2 ceramic membranes modified with silver-functionalized copper oxide (Ag-CuO) nanoparticles are reported for the improved separation performance of emulsified oil. Ag-CuO nanoparticles were synthesized via hydrothermal technique and dip-coated onto commercial membranes at varying concentrations (0.1, 0.5, and 1.0 wt.%). The prepared membranes were further examined to understand the improvements in oil-water separation due to Ag-CuO coating. All modified ceramic membranes exhibited higher hydrophilicity and decreased porosity. Additionally, the permeate flux, oil rejection, and antifouling performance of the Ag-CuO-coated membranes were more significantly improved than the pristine commercial membrane. The 0.5 wt.% modified membrane exhibited a 30% higher water flux (303.63 L m−2 h−1) and better oil rejection efficiency (97.8%) for oil/water separation among the modified membranes. After several separation cycles, the 0.5 wt.% Ag-CuO-modified membranes showed a constant permeate flux with an excellent oil rejection of >95% compared with the unmodified membrane. Moreover, the corrosion resistance of the coated membrane against acid, alkali, actual seawater, and oily wastewater was remarkable. Thus, the Ag-CuO-modified ceramic membranes are promising for oil separation applications due to their high flux, enhanced oil rejection, better antifouling characteristics, and good stability.
24
Ahmad, Fatin Nurwahdah, Norazlianie Sazali e Mohd Hafiz Dzafran Othman. "A Mini Review on Carbon Molecular Sieve Membrane for Oxygen Separation". Journal of Modern Manufacturing Systems and Technology 4, n. 1 (27 marzo 2020): 23–35. http://dx.doi.org/10.15282/jmmst.v4i1.3800.
Testo completoAbstract (sommario):
Membrane-based technology has proved its practicality in gas separation through its performance. Various type of membranes has been explored, showing that each type of them have their own advantages and disadvantages. Polymeric membranes have been widely used to separate O2/N2, however, its drawbacks lead to the development of carbon molecular sieve membrane. Carbon molecular sieve membranes have demonstrated excellent separation performance for almost similar kinetic diameter molecules such as O2/N2. Many polymer precursors can be used to produce carbon molecular sieve membrane through carbonization process or also known as heat treatment. This paper discusses the variety of precursors and carbonization parameters to produce high quality and performance of carbon molecular sieve membranes. This paper covers the evaluation in advancement and status of high-performance carbon membrane implemented for separating gas, comprising the variety of precursor materials and the fabrication process that involve many different parameters, also analysis of carbon membranes properties in separating various type of gas having high demand in the industries. The issues regarding the current challenges in developing carbon membrane and approaches with the purpose of solving and improving the performance and applications of carbon membrane are included in this paper. Also, the advantages of the carbon membrane compared to other types of membranes are highlighted. Observation and understanding the variables affecting the quality of membrane encourage the optimization of conditions and techniques in producing high-performance membrane.
25
Shekhah, Osama, Valeriya Chernikova, Youssef Belmabkhout e Mohamed Eddaoudi. "Metal–Organic Framework Membranes: From Fabrication to Gas Separation". Crystals 8, n. 11 (31 ottobre 2018): 412. http://dx.doi.org/10.3390/cryst8110412.
Testo completoAbstract (sommario):
Gas membrane-based separation is considered one of the most effective technologies to address energy efficiency and large footprint challenges. Various classes of advanced materials, including polymers, zeolites, porous carbons, and metal–organic frameworks (MOFs) have been investigated as potential suitable candidates for gas membrane-based separations. MOFs possess a uniquely tunable nature in which the pore size and environment can be controlled by connecting metal ions (or metal ion clusters) with organic linkers of various functionalities. This unique characteristic makes them attractive for the fabrication of thin membranes, as both the diffusion and solubility components of permeability can be altered. Numerous studies have been published on the synthesis and applications of MOFs, as well as the fabrication of MOF-based thin films. However, few studies have addressed their gas separation properties for potential applications in membrane-based separation technologies. Here, we present a synopsis of the different types of MOF-based membranes that have been fabricated over the past decade. In this review, we start with a short introduction touching on the gas separation membrane technology. We also shed light on the various techniques developed for the fabrication of MOF as membranes, and the key challenges that still need to be tackled before MOF-based membranes can successfully be used in gas separation and implemented in an industrial setting.
26
Pei, Xueliang, Lei Zhang, Yongqian Ma, Hengtong Zhang, Xinxin Zhao e Yonghai Gao. "Research on Downhole Gas Separation Method Based on a PDMS Separation Membrane". Energies 16, n. 10 (22 maggio 2023): 4255. http://dx.doi.org/10.3390/en16104255.
Testo completoAbstract (sommario):
Safe and efficient deep drilling is a fundamental requirement for the development of oil and gas resources. In this regard, the application of membrane separation technology for drilling fluid gas separation and monitoring is highly significant. In this study, several commonly used permeable membrane materials were analyzed, and a PDMS separation membrane was preliminarily selected as a suitable material for downhole gas separation. We designed an experimental setup to investigate the separation performance of PDMS membranes. The effects of the separation pressure difference, operating temperature, and membrane thickness on the performance of PDMS membranes were analyzed, and the microstructure changes in the PDMS membrane under high temperature and pressure were observed using a scanning electron microscopy. The experimental results showed that PDMS membranes with a thickness of 150–200 μm can work stably and maintain good strength and permeability at a separation pressure difference of 1.1 MPa and a temperature of 150 °C. The SEM observations revealed that the PDMS separation membrane had a smooth surface and uniform microstructure after continuous operations for 15 h under the temperature and pressure conditions, without any cracks, demonstrating high temperature and pressure resistance. These research results provide an important reference for the application of PDMS separation membranes in downhole gas separation technology.
27
Yi, Shouliang, Bader Ghanem, Yang Liu, Ingo Pinnau e William J. Koros. "Ultraselective glassy polymer membranes with unprecedented performance for energy-efficient sour gas separation". Science Advances 5, n. 5 (maggio 2019): eaaw5459. http://dx.doi.org/10.1126/sciadv.aaw5459.
Testo completoAbstract (sommario):
Membrane-based separation of combined acid gases carbon dioxide and hydrogen sulfide from natural gas streams has attracted increasing academic and commercial interest. These feeds are referred to as “sour,” and herein, we report an ultra H2S-selective and exceptionally permeable glassy amidoxime-functionalized polymer of intrinsic microporosity for membrane-based separation. A ternary feed mixture (with 20% H2S:20% CO2:60% CH4) was used to demonstrate that a glassy amidoxime-functionalized membrane provides unprecedented separation performance under challenging feed pressures up to 77 bar. These membranes show extraordinary H2S/CH4 selectivity up to 75 with ultrahigh H2S permeability >4000 Barrers, two to three orders of magnitude higher than commercially available glassy polymeric membranes. We demonstrate that the postsynthesis functionalization of hyper-rigid polymers with appropriate functional polar groups provides a unique design strategy for achieving ultraselective and highly permeable membrane materials for practical natural gas sweetening and additional challenging gas pair separations.
28
Lau, Woei-Jye, e Antonia Pérez de los Ríos. "Membrane Separation". Chemical Engineering & Technology 41, n. 2 (29 gennaio 2018): 210. http://dx.doi.org/10.1002/ceat.201870025.
Testo completo
29
Tang, Chao, Andriy Yaroshchuk e Merlin L. Bruening. "Ion Separations Based on Spontaneously Arising Streaming Potentials in Rotating Isoporous Membranes". Membranes 12, n. 6 (18 giugno 2022): 631. http://dx.doi.org/10.3390/membranes12060631.
Testo completoAbstract (sommario):
Highly selective ion separations are vital for producing pure salts, and membrane-based separations are promising alternatives to conventional ion-separation techniques. Our previous work demonstrated that simple pressure-driven flow through negatively charged isoporous membranes can separate Li+ and K+ with selectivities as high as 70 in dilute solutions. The separation mechanism relies on spontaneously arising streaming potentials that induce electromigration, which opposes advection and separates cations based on differences in their electrophoretic mobilities. Although the separation technique is simple, this work shows that high selectivities are possible only with careful consideration of experimental conditions including transmembrane pressure, solution ionic strength, the K+/Li+ ratio in the feed, and the extent of concentration polarization. Separations conducted with a rotating membrane show Li+/K+ selectivities as high as 150 with a 1000 rpm membrane rotation rate, but the selectivity decreases to 1.3 at 95 rpm. These results demonstrate the benefits and necessity of quantitative control of concentration polarization in highly selective separations. Increases in solution ionic strength or the K+/Li+ feed ratio can also decrease selectivities more than an order of magnitude.
30
Katia Cecilia, de Souza Figueiredo, de Jesus Barcelos Gustavo Feliciano e Ferlauto André Santarosa. "Graphene Membranes: From Reverse Osmosis to Gas Separation". International Journal of Membrane Science and Technology 8, n. 2 (16 novembre 2021): 1–27. http://dx.doi.org/10.15379/2410-1869.2021.08.02.01.
Testo completoAbstract (sommario):
Graphene membrane is a promising technology to help both carbon dioxide separation from flue gas and water desalination. This work reported the importance of membrane separation processes, the evolution of polymeric membranes before the discovery of graphene and how this material fits into this scenario. In addition, reverse osmosis and gas separations have been discussed as promising methods to reduce the occurrence of freshwater scarcity events and slow global warming. For all these separation techniques, the current state of graphene membranes technology and what advances might be brought by such one atom thick skin layer were presented, as well as the results of theoretical and experimental research. Finally, the challenges that still need to be overcome by this innovative technology as well as the perspectives were shown.
31
Matsumoto, Kanji, e Kazuho Nakamura. "Membrane Separation in Bioseparation." membrane 21, n. 1 (1996): 49–56. http://dx.doi.org/10.5360/membrane.21.49.
Testo completo
32
Kurimura, Hideki. "Oxygen Separation". MEMBRANE 31, n. 1 (2006): 12–13. http://dx.doi.org/10.5360/membrane.31.12.
Testo completo
33
Matsukata, Masahiko. "Hydrocarbon Separation". MEMBRANE 31, n. 1 (2006): 18–19. http://dx.doi.org/10.5360/membrane.31.18.
Testo completo
34
Kusuki, Yoshihiro. "Preparation and Application of Carbon Dioxide Separation Membrane and Hydrogen Separation Membrane." membrane 21, n. 5 (1996): 276–82. http://dx.doi.org/10.5360/membrane.21.276.
Testo completo
35
Melnik, Alexandra, Alena Bogoslovtseva, Anna Petrova, Alexey Safonov e Christos N. Markides. "Oil–Water Separation on Hydrophobic and Superhydrophobic Membranes Made of Stainless Steel Meshes with Fluoropolymer Coatings". Water 15, n. 7 (30 marzo 2023): 1346. http://dx.doi.org/10.3390/w15071346.
Testo completoAbstract (sommario):
In this work, membranes were synthesized by depositing fluoropolymer coatings onto metal meshes using the hot wire chemical vapor deposition (HW CVD) method. By changing the deposition parameters, membranes with different wetting angles were obtained, with water contact angles for different membranes over a range from 130° ± 5° to 170° ± 2° and a constant oil contact angle of about 80° ± 2°. These membranes were used for the separation of an oil–water emulsion in a simple filtration test. The main parameters affecting the separation efficiency and the optimal separation mode were determined. The results reveal the effectiveness of the use of the membranes for the separation of emulsions of water and commercial crude oil, with separation efficiency values that can reach over 99%. The membranes are most efficient when separating emulsions with a water concentration of less than 5%. The pore size of the membrane significantly affects the rate and efficiency of separation. Pore sizes in the range from 40 to 200 µm are investigated. The smaller the pore size of the membranes, the higher the separation efficiency. The work is of great economic and practical importance for improving the efficiency of the membrane separation of oil–water emulsions. It lays the foundation for future research on the use of hydrophobic membranes for the separation of various emulsions of water and oil products (diesel fuel, gasoline, kerosene, etc.).
36
Borpatra Gohain, Moucham, Sachin Karki, Diksha Yadav, Archana Yadav, Neha R. Thakare, Swapnali Hazarika, Hyung Keun Lee e Pravin G. Ingole. "Development of Antifouling Thin-Film Composite/Nanocomposite Membranes for Removal of Phosphate and Malachite Green Dye". Membranes 12, n. 8 (7 agosto 2022): 768. http://dx.doi.org/10.3390/membranes12080768.
Testo completoAbstract (sommario):
Nowadays polymer-based thin film nanocomposite (TFN) membrane technologies are showing key interest to improve the separation properties. TFN membranes are well known in diverse fields but developing highly improved TFN membranes for the removal of low concentration solutions is the main challenge for the researchers. Application of functional nanomaterials, incorporated in TFN membranes provides better performance as permeance and selectivity. The polymer membrane-based separation process plays an important role in the chemical industry for the isolation of products and recovery of different important types of reactants. Due to the reduction in investment, less operating costs and safety issues membrane methods are mainly used for the separation process. Membranes do good separation of dyes and ions, yet their separation efficiency is challenged when the impurity is in low concentration. Herewith, we have developed, UiO-66-NH2 incorporated TFN membranes through interfacial polymerization between piperazine (PIP) and trimesoyl chloride (TMC) for separating malachite green dye and phosphate from water in their low concentration. A comparative study between thin-film composite (TFC) and TFN has been carried out to comprehend the benefit of loading nanoparticles. To provide mechanical strength to the polyamide layer ultra-porous polysulfone support was made through phase inversion. As a result, outstanding separation values of malachite green (MG) 91.90 ± 3% rejection with 13.32 ± 0.6 Lm−2h−1 flux and phosphate 78.36 ± 3% rejection with 22.22 ± 1.1 Lm−2h−1 flux by TFN membrane were obtained. The antifouling tendency of the membranes was examined by using bovine serum albumin (BSA)-mixed feed and deionized water, the study showed a good ~84% antifouling tendency of TFN membrane with a small ~14% irreversible fouling. Membrane’s antibacterial test against E. coli. and S. aureus. also revealed that the TFN membrane possesses antibacterial activity as well. We believe that the present work is an approach to obtaining good results from the membranes under tricky conditions.
37
Du, Jing, Jilei Jiang, Zhigang Xue, Yajing Hu, Bo Liu, Rongfei Zhou e Weihong Xing. "Template-Free Synthesis of High Dehydration Performance CHA Zeolite Membranes with Increased Si/Al Ratio Using SSZ-13 Seeds". Membranes 14, n. 4 (27 marzo 2024): 78. http://dx.doi.org/10.3390/membranes14040078.
Testo completoAbstract (sommario):
Pervaporation is an energy-efficient alternative to conventional distillation for water/alcohol separations. In this work, a novel CHA zeolite membrane with an increased Si/Al ratio was synthesized in the absence of organic templates for the first time. Nanosized high-silica zeolite (SSZ-13) seeds were used for the secondary growth of the membrane. The separation performance of membranes in different alcohol–aqueous mixtures was measured. The effects of water content in the feed and the temperature on the separation performance using pervaporation and vapor permeation were also studied. The best membrane showed a water/ethanol separation factor above 100,000 and a total flux of 1.2 kg/(m2 h) at 348 K in a 10 wt.% water–ethanol mixed solution. A membrane with high performance and an increased Si/Al ratio is promising for the application of alcohol dehydration.
38
Schmeling, Nadine, Roman Konietzny, Daniel Sieffert, Patrick Rölling e Claudia Staudt. "Functionalized copolyimide membranes for the separation of gaseous and liquid mixtures". Beilstein Journal of Organic Chemistry 6 (12 agosto 2010): 789–800. http://dx.doi.org/10.3762/bjoc.6.86.
Testo completoAbstract (sommario):
Functionalized copolyimides continue to attract much attention as membrane materials because they can fulfill the demands for industrial applications. Thus not only good separation characteristics but also high temperature stability and chemical resistance are required. Furthermore, it is very important that membrane materials are resistant to plasticization since it has been shown that this phenomenon leads to a significant increase in permeability with a dramatic loss in selectivity. Plasticization effects occur with most polymer membranes at high CO2 concentrations and pressures, respectively. Plasticization effects are also observed with higher hydrocarbons such as propylene, propane, aromatics or sulfur containing aromatics. Unfortunately, these components are present in mixtures of high commercial relevance and can be separated economically by single membrane units or hybrid processes where conventional separation units are combined with membrane-based processes. In this paper the advantages of carboxy group containing 6FDA (4,4′-hexafluoroisopropylidene diphthalic anhydride) -copolyimides are discussed based on the experimental results for non cross-linked, ionically and covalently cross-linked membrane materials with respect to the separation of olefins/paraffins, e.g. propylene/propane, aromatic/aliphatic separation e.g. benzene/cyclohexane as well as high pressure gas separations, e.g. CO2/CH4 mixtures. In addition, opportunities for implementing the membrane units in conventional separation processes are discussed.
39
Xie, Zean, Xinping Wang, Lu Li e Jinhui Pang. "Separation of methyl glycosides and glycerol from aqueous fraction of methyl bio-oils using nanofiltration". BioResources 14, n. 1 (30 novembre 2018): 575–91. http://dx.doi.org/10.15376/biores.14.1.575-591.
Testo completoAbstract (sommario):
The feasibility of separating small molecular organic compounds in the aqueous fraction of methyl bio-oils (AFMBO) using nanofiltration (NF) and reverse osmosis (RO) membranes was studied. Four kinds of commercially available NF and RO membranes were studied preliminarily by using model solutions (aqueous solution of methyl glycosides and glycerol). The membrane module was spiral wound, which is a more suitable format for industrialization than the flat-sheet format for dead-end filtration. The NF400-600 membrane exhibited the best separation performance; the permeate flux was 48.6 L/(m2·h), the methyl glucosides (MEG) rejection ratio was 95.4%, and the transmission of glycerol was 81.0% with an initial concentration of 10 g/L (0.4 MPa, 45 ºC). Compared with the model solution, the NF performance of AFMBO, which included permeate flux, rejection of MEG, transmission of glycerol, and separation of the other components in AFMBO, was investigated. The more complex constituents of AFMBO led to NF400-600 permeability and separating property decline compared with the model solution in the same operating conditions; meanwhile more serious and even irreversible membrane fouling occurred. This research provided a reference for membrane separation industrial feasibility and application of AFMBO.
40
Zhou, Qibo, Qibing Chang, Yao Lu e Jing Sun. "Mussel-Inspired Construction of Silica-Decorated Ceramic Membranes for Oil–Water Separation". Ceramics 7, n. 1 (22 febbraio 2024): 250–63. http://dx.doi.org/10.3390/ceramics7010016.
Testo completoAbstract (sommario):
In recent years, ceramic membranes have received widespread focus in the area of liquid separation because of their high permeability, strong hydrophilicity, and good chemical stability. However, in practical applications, the surface of ceramic membranes is prone to be contaminated, which degrades the permeation flux of ceramic membranes during the separation process. Inspired by mussels, we imitate the biomimetic mineralization process to prepare a ceramic membrane of nano–silica on the pre-modified zirconia surface by co-deposited polydopamine/polyethyleneimine. The modified ceramic membranes were utilized for the purpose of oil–water separation. Separation performance has been tested using a disc ceramic membrane dynamic filtration device. The outcomes revealed an enhanced permeability in the modified membrane, measuring as 159 L m−2 h−1 bar−1, surpassing the separation flux of the unmodified membrane, which was 104 L m−2 h−1 bar−1. The permeation performance of the modified membrane was increased to 1.5 times. Modified ceramic membranes are highly resistant to fouling. From the beginning to the end of separation process, the oil rejection rate of the modified ceramic membrane is always higher than 99%. After a 2 h oil–water separation test run, modified ceramic membrane permeate flux can be restored to 91% after cleaning. It has an enormous capacity for application in the area of oil–water separation.
41
Abejón, Ricardo, Clara Casado-Coterillo e Aurora Garea. "Multiobjective Optimization Based on “Distance-to-Target” Approach of Membrane Units for Separation of CO2/CH4". Processes 9, n. 11 (21 ottobre 2021): 1871. http://dx.doi.org/10.3390/pr9111871.
Testo completoAbstract (sommario):
The effective separation of CO2 and CH4 mixtures is essential for many applications, such as biogas upgrading, natural gas sweetening or enhanced oil recovery. Membrane separations can contribute greatly in these tasks, and innovative membrane materials are being developed for this gas separation. The aim of this work is the evaluation of the potential of two types of highly CO2-permeable membranes (modified commercial polydimethylsiloxane and non-commercial ionic liquid–chitosan composite membranes) whose selective layers possess different hydrophobic and hydrophilic characteristics for the separation of CO2/CH4 mixtures. The study of the technical performance of the selected membranes can provide a better understanding of their potentiality. The optimization of the performance of hollow fiber modules for both types of membranes was carried out by a “distance-to-target” approach that considered multiple objectives related to the purities and recovery of both gases. The results demonstrated that the ionic liquid–chitosan composite membranes improved the performance of other innovative membranes, with purity and recovery percentage values of 86 and 95%, respectively, for CO2 in the permeate stream, and 97 and 92% for CH4 in the retentate stream. The developed multiobjective optimization allowed for the determination of the optimal process design and performance parameters, such as the membrane area, pressure ratio and stage cut required to achieve maximum values for component separation in terms of purity and recovery. Since the purities and recoveries obtained were not enough to fulfill the requirements imposed on CO2 and CH4 streams to be directly valorized, the design of more complex multi-stage separation systems was also proposed by the application of this optimization methodology, which is considered as a useful tool to advance the implementation of the membrane separation processes.
42
Ji, Tong, Yuan Ji, Xiangli Meng e Qi Wang. "Temperature-Responsive Separation Membrane with High Antifouling Performance for Efficient Separation". Polymers 16, n. 3 (1 febbraio 2024): 416. http://dx.doi.org/10.3390/polym16030416.
Testo completoAbstract (sommario):
Temperature-responsive separation membranes can significantly change their permeability and separation properties in response to changes in their surrounding temperature, improving efficiency and reducing membrane costs. This study focuses on the modification of polyvinylidene fluoride (PVDF) membranes with amphiphilic temperature-responsive copolymer and inorganic nanoparticles. We prepared an amphiphilic temperature-responsive copolymer in which the hydrophilic poly(N-isopropyl acrylamide) (PNIPAAm) was side-linked to a hydrophobic polyvinylidene fluoride (PVDF) skeleton. Subsequently, PVDF-g-PNIPAAm polymer and graphene oxide (GO) were blended with PVDF to prepare temperature-responsive separation membranes. The results showed that temperature-responsive polymers with different NIPAAm grafting ratios were successfully prepared by adjusting the material ratio of NIPAAm to PVDF. PVDF-g-PNIPAAm was blended with PVDF with different grafting ratios to obtain separate membranes with different temperature responses. GO and PVDF-g-PNIPAAm formed a relatively stable hydrogen bond network, which improved the internal structure and antifouling performance of the membrane without affecting the temperature response, thus extending the service life of the membrane.
43
Fain, D. E. "Membrane Gas Separation Principles". MRS Bulletin 19, n. 4 (aprile 1994): 40–43. http://dx.doi.org/10.1557/s0883769400039506.
Testo completoAbstract (sommario):
Some industrial processes require the separation of gas or vapor mixtures. Methods for separating the mixtures vary from separation by diffusion to separation by distillation. Many of the methods, such as distillation, are energy intensive. Membranes can reduce the energy required to produce a desired separation. Because of their corrosion resistance and high temperature applications, engineered inorganic membranes can significantly increase the efficiency of many of these processes. The magnitude of the separation factor, available operating conditions, enrichment, yield, and cost of the membranes play a large role in determining whether membranes can be more economical than other methods of separation. These factors have to be evaluated on a case-by-case basis.Martin Marietta Energy Systems' Office of Technology Transfer conducted a preliminary market survey with the assistance of the University of Tennessee and commercial marketing experts in inorganic membranes. The survey assumed that membranes could be made with permeabilities a factor of 3 larger and with cost per unit area a factor of 3 smaller than is currently available. The results indicated that active implementation of such technology could expect to achieve the following results:• $2 billion dollar per year sales market,• $16.6 billion increase in the national GDP,• $2 billion improvement in the balance of trade, and• 6 quads per year decrease in energy use.
44
Mohshim, Dzeti Farhah, Hilmi bin Mukhtar, Zakaria Man e Rizwan Nasir. "Latest Development on Membrane Fabrication for Natural Gas Purification: A Review". Journal of Engineering 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/101746.
Testo completoAbstract (sommario):
In the last few decades, membrane technology has been a great attention for gas separation technology especially for natural gas sweetening. The intrinsic character of membranes makes them fit for process escalation, and this versatility could be the significant factor to induce membrane technology in most gas separation areas. Membranes were synthesized with various materials which depended on the applications. The fabrication of polymeric membrane was one of the fastest growing fields of membrane technology. However, polymeric membranes could not meet the separation performances required especially in high operating pressure due to deficiencies problem. The chemistry and structure of support materials like inorganic membranes were also one of the focus areas when inorganic membranes showed some positive results towards gas separation. However, the materials are somewhat lacking to meet the separation performance requirement. Mixed matrix membrane (MMM) which is comprising polymeric and inorganic membranes presents an interesting approach for enhancing the separation performance. Nevertheless, MMM is yet to be commercialized as the material combinations are still in the research stage. This paper highlights the potential promising areas of research in gas separation by taking into account the material selections and the addition of a third component for conventional MMM.
45
Fazullin, D. D., G. V. Mavrin e I. G. Shaikhiev. "Air Cleaning from Organic Compounds Using a Nanofiltration Composite Membrane Based on Cellulose Acetate and a Commercial Membrane of OPMN-P Brand". Мембраны и мембранные технологии 13, n. 1 (1 gennaio 2023): 56–64. http://dx.doi.org/10.31857/s2218117223010029.
Testo completoAbstract (sommario):
Nanofiltration membranes were used to separate the vapor–air mixture containing organic compounds. The membrane was obtained on a filter paper substrate by pouring with a three-component polymer solution. The surface layers were deposited on the substrate by sequentially alternating the stages of membrane drying. The resulting membrane has hydrophilic properties, the porosity of the resulting membrane is 51%. The membrane thickness determined by SEM was 98 µm. The retention capacity of the membranes was studied by separating model mixtures of ethanol–air and gasoline–air. The membrane permeability of the MAC3 composite membrane during separation of the ethanol–air vapor-air mixture was 11.0 m3/m2h at a pressure of 0.5 MPa. The high retention capacity of the MAC3 composite membrane was established for xylenes, toluene, and heptane; for other compounds, the efficiency is no more than 90%. The average retention capacity of the resulting membrane was 87%. Comparative tests to establish gas separation parameters under similar conditions were carried out with a commercial membrane brand OPMN-P.
46
Lapišová, K., R. Vlček, J. Klozová, M. Rychtera e K. Melzoch. "Separation techniques for distillery stillage treatment". Czech Journal of Food Sciences 24, No. 6 (12 novembre 2011): 261–67. http://dx.doi.org/10.17221/3323-cjfs.
Testo completoAbstract (sommario):
The separation of stillage was tested by means of the pilot plantARNO600-BIO using three-channel ceramic membranes with the pore diameter range from microfiltration to ultrafiltration (1.4 µm–5 kDa). The permeate from the last membrane step was able to be recycled as technological water. The best results were achieved in the arrangement of series using 0.2 µm membrane as the first step supplemented by ultra-filtration membranes (50 kDa and 15 kDa), predominantly, where the reduction of the chemical oxygen demand (COD) extended 80%. With this process, we try to get some advantages over the conventional process in terms of eliminating both land and energy costs for the wastewater treatment process and improving the quality of the discharge water. The main goal in this study is to analyse different separation steps and conditions to find both the best separation options for the decrease of the final volume of distillery stillage, and the way how to make the bio ethanol production more profitable.
47
Da Conceicao, Marcos, Leo Nemetz, Joanna Rivero, Katherine Hornbostel e Glenn Lipscomb. "Gas Separation Membrane Module Modeling: A Comprehensive Review". Membranes 13, n. 7 (30 giugno 2023): 639. http://dx.doi.org/10.3390/membranes13070639.
Testo completoAbstract (sommario):
Membrane gas separation processes have been developed for diverse gas separation applications that include nitrogen production from air and CO2 capture from point sources. Membrane process design requires the development of stable and robust mathematical models that can accurately quantify the performance of the membrane modules used in the process. The literature related to modeling membrane gas separation modules and model use in membrane gas separation process simulators is reviewed in this paper. A membrane-module-modeling checklist is proposed to guide modeling efforts for the research and development of new gas separation membranes.
48
Asim Mushtaq, Asim Mushtaq, e Hilmi Mukhtar and Azmi Mohd Shariff Hilmi Mukhtar and Azmi Mohd Shariff. "Recent Development of Enhanced Polymeric Blend Membranes in Gas Separation: A Review". Journal of the chemical society of pakistan 42, n. 2 (2020): 282. http://dx.doi.org/10.52568/000635.
Testo completoAbstract (sommario):
Natural gas is the most rapid growing energy sources around the world. The presence of CO2 in natural gas lowers its calorific value and purification of a natural gas by removing CO2 is an essential process to increase its value. Several separation technologies are used to remove acidic gases like H2S and CO2 from natural gas. Among these technologies, membrane process is a feasible energy saving alternate to CO2 capture. The three types of membrane include polymeric, inorganic and mixed matrix membranes. Currently, polymer membranes and inorganic membranes were considered for gas separation, but inorganic membranes are too costly. Even mixed matrix membrane performance suffered defects caused by poor glassy polymer and particle interactions. Pure glassy and pure rubbery are problematic due to their instructive properties. The blending of glassy with rubbery polymers improve membrane properties for gas separation. To enhance the compatibility of the polymer blend, a third component is added such as alkanol amines. Although, the enhanced polymeric blend membranes have many advantages in terms of permeance, selectivity, thermal and chemical stability. Polymer blending also offers an effective technique to synthesize membranes with desirable properties.
49
Asim Mushtaq, Asim Mushtaq, e Hilmi Mukhtar and Azmi Mohd Shariff Hilmi Mukhtar and Azmi Mohd Shariff. "Recent Development of Enhanced Polymeric Blend Membranes in Gas Separation: A Review". Journal of the chemical society of pakistan 42, n. 2 (2020): 282. http://dx.doi.org/10.52568/000635/jcsp/42.02.2020.
Testo completoAbstract (sommario):
Natural gas is the most rapid growing energy sources around the world. The presence of CO2 in natural gas lowers its calorific value and purification of a natural gas by removing CO2 is an essential process to increase its value. Several separation technologies are used to remove acidic gases like H2S and CO2 from natural gas. Among these technologies, membrane process is a feasible energy saving alternate to CO2 capture. The three types of membrane include polymeric, inorganic and mixed matrix membranes. Currently, polymer membranes and inorganic membranes were considered for gas separation, but inorganic membranes are too costly. Even mixed matrix membrane performance suffered defects caused by poor glassy polymer and particle interactions. Pure glassy and pure rubbery are problematic due to their instructive properties. The blending of glassy with rubbery polymers improve membrane properties for gas separation. To enhance the compatibility of the polymer blend, a third component is added such as alkanol amines. Although, the enhanced polymeric blend membranes have many advantages in terms of permeance, selectivity, thermal and chemical stability. Polymer blending also offers an effective technique to synthesize membranes with desirable properties.
50
Wang, Luchen, Yan Wang, Lianying Wu e Gang Wei. "Fabrication, Properties, Performances, and Separation Application of Polymeric Pervaporation Membranes: A Review". Polymers 12, n. 7 (30 giugno 2020): 1466. http://dx.doi.org/10.3390/polym12071466.
Testo completoAbstract (sommario):
Membrane separation technologies have attracted great attentions in chemical engineering, food science, analytical science, and environmental science. Compared to traditional membrane separation techniques like reverse osmosis (RO), ultrafiltration (UF), electrodialysis (ED) and others, pervaporation (PV)-based membrane separation shows not only mutual advantages such as small floor area, simplicity, and flexibility, but also unique characteristics including low cost as well as high energy and separation efficiency. Recently, different polymer, ceramic and composite membranes have shown promising separation applications through the PV-based techniques. To show the importance of PV for membrane separation applications, we present recent advances in the fabrication, properties and performances of polymeric membranes for PV separation of various chemicals in petrochemical, desalination, medicine, food, environmental protection, and other industrial fields. To promote the easy understanding of readers, the preparation methods and the PV separation mechanisms of various polymer membranes are introduced and discussed in detail. This work will be helpful for developing novel functional polymer-based membranes and facile techniques to promote the applications of PV techniques in different fields.