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• Thermodynamic analysis of a novel two-stage ejector refrigeration cycle is made. • Cycle performance and exergy efficiency are improved by the separation of mixtures. • COP improvement increased by 41.6 % and 89.6 % for 134a/R32 and R600a/R290. • Three largest exergy destruction occurs in the ejector, condenser, and generator. To improve the ejector refrigeration cycle performance, this paper presents a theoretical thermodynamic analysis of a novel two-stage ejector refrigeration cycle (TSERC) with a gas-liquid separator using R134a/R32 and R600a/R290 as refrigerant. By separating the relatively low-boiling-point and high-boiling-point refrigerants, the cycle compression ratio decreases, the cycle performance increases, and the energy utilization efficiency can be improved. Energy and exergy analysis were conducted for the traditional single-stage ejector refrigeration cycle (SSERC) and TSERC. The effect of the mixture mass fraction on cycle performance under a fixed external heat source operating condition was studied, and the cycle performance comparisons between TSERC and SSERC at different evaporation temperature, condensation temperature and generation temperature were conducted. Results show that for TSERC, the maximum COP values 0.126 and 0.11, the maximum exergy efficiency 4.51 % and 4 % are obtained as the low-boiling-point mass fraction equals 0.6 and 0.4 respectively for R134a/R32 and R600a/R290. It is found that exergy destruction mainly occurs in the low-pressure sub-cycle of TSERC, the top three largest exergy destruction components are ejector 1, condenser 1 and generator 1, while the smallest exergy destruction occurs in pump 2. In addition, cycle performance comparison between SSERC and TSERC shows that the maximum COP improvement increased by 41.6 % and 89.6 % for 134a/R32 and R600a/R290 for TSERC, while the maximum entrainment ratio improvement increased by 32.4 % and 87.6 %. Moreover, it is concluded that the cycle performance improvement of TSERC is more significant at lower evaporation temperature, higher condensation temperature, and lower generation temperature compared to SSERC. [ABSTRACT FROM AUTHOR]

Gelatin, a natural protein, is extensively used in the food, pharmaceutical, and cosmetics industries. However, purifying gelatin to meet the specific requirements of various industries remains a considerable challenge. Ceramic membrane separation technology, renowned for its high permeability, excellent anti-fouling properties, and long lifespan, has been widely applied in the food, biotechnology, and water purification industries. In this study, a sol-gel method was employed to fabricate a gradient multilayer TiO 2 -modified coating on the surface of an α-Al 2 O 3 porous ceramic membrane. The viscosity of the TiO 2 sols was adjusted by varying the concentrations of polyethylene glycol (PEG 2000) and aging times. The results indicated that coating the C-P5^5 composite membrane with a sol containing 5 wt% PEG, aged for different durations (2, 5, 10, 15, and 18 d), effectively reduced the weight-average molecular weight (M w) of the permeate from the feed solution of 52.4 kDa–11.9 kDa. However, the C-P10^5 composite membrane, with a 10 wt% PEG content and aged for the same durations, yielded a permeate gelatin M w of 13.6 kDa. The composite membrane with excellent anti-fouling and photocatalytic self-cleaning properties holds promise for innovative applications in gelatin purification and bio-separation processes. [Display omitted] [ABSTRACT FROM AUTHOR]

Understanding the nanotransport properties of NH 3 and H 2 is critical for designing adsorption and separation materials. In this work, we develop a novel numerical model at the molecular level by incorporating the M − S approach and effective medium theory, and provide a rigorous and analyzable simulation implementation for a binary transport system of NH 3 and H 2. In addition, the effect of pore length nonuniformity is simultaneously incorporated. The results show that high temperatures and large radii are detrimental to adsorption but favorable for diffusion at the single-pore scale, while the greater conductance increase in large pores dominates the fluid transport property in the pore network. The existence of a pore length distribution can induce greater effective diffusivity and lower apparent tortuosity within the pore network. Moreover, we confirm that at 300 K, the equilibrium selectivity of NH 3 over H 2 reaches approximately 28 in a uniform pore network with a pore radius of 0.25 nm, indicating the feasibility of nanoporous silica materials for use in adsorption separation of NH 3 and H 2 mixtures. [Display omitted] • Numerical transport model of NH 3 /H 2 mixture is built based on the M − S theory. • Competitive effect of adsorption and diffusion of fluid in nanopore is analyzed. • Influence of pore length distribution on fluid transport is discussed. • Possible strategy of NH 3 /H 2 mixture separation by Nano-porous silica is proposed. [ABSTRACT FROM AUTHOR]

Ammonia production has traditionally been done by using the Haber-Bosch process, that operates at extremely high pressure (200–300 bar), has a large carbon footprint, and requires significant energy. For ammonia to be used as a hydrogen carrier, it is desired that it is produced by using modular technologies under benign conditions, yet the economics remain commercially viable. This paper investigates a novel technology for ammonia synthesis by using a microwave-assisted low-pressure reactor. Microwave reactors are compact and can be readily modularized and started/shutdown thus making them ideal to be integrated with the electric grid or with regional/local renewable-based electric generation facilities. For separation of unreacted reactants from the product ammonia, if the traditional condensation separation technology used in the high-pressure Haber-Bosch process is used, then the separation process needs to be operated under cryogenic condition thus adversely affecting the economics. A solid sorbent based separation technology is investigated in this paper. A kinetic model for the microwave-catalytic synthesis process is used. An isotherm model is developed for MgCl 2 –Si adsorbent and used for modeling the dynamic adsorption-desorption cycle. A plant-wide model with heat and mass integration is developed. An economic model is developed and used for economic optimization by using an equation-oriented approach. Since the adsorption-desorption process is dynamic, for techno-economic optimization, a reduced order model for the key performance measures of the adsorption-desorption process as a function of its input and decision variable is developed under cyclic steady-state conditions. For the optimized MW-assisted process, the levelized cost of ammonia is $772/mt as opposed to $808/mt for the conventional Haber-Bosch process for a hydrogen price of $2.07/kg. The MW-assisted process is found to be economically viable in the US market if the hydrogen price is below $4/kg. • Plant-wide model of a novel MW-assisted ammonia synthesis process is developed. • A solid-sorbent based separation technology is investigated for separation. • A reduced model based approach is developed for optimizing the adsorption process. • For the optimized process, the levelized cost of ammonia is found to be $772/mt. • The technology is found to be economically viable for H 2 price below $4/kg. [ABSTRACT FROM AUTHOR]

Metal-based membranes have emerged as a promising solution, providing selective permeability and impressive durability. However, a comprehensive understanding of their environmental performance across their entire life cycle remains elusive. This research offers a comprehensive life cycle assessment (LCA) of electroless plated palladium alloy-based membranes for hydrogen separation. It evaluates the environmental impacts across various stages, from the synthesis of supports to the application of intermediate and selective layers. Key findings include the identification of alumina supports and graphite intermediate layers as having minimal environmental impacts, and the Pd–Cu membrane as the most sustainable choice among palladium alloy membranes. This research advances our understanding of the eco-friendly performance of palladium based H 2 separation membranes, guiding the development of more sustainable hydrogen separation technologies. [Display omitted] • Environmental comparison of support, intermediate, and selective layers in metal-based H 2 separation membranes. • Use of the Electroless Plating method. • Alumina supports have the least environmental impact. • Graphite layers offer the lowest comprehensive environmental effects across various categories for the intermediate layers. • Pd–Cu membrane is the most sustainable choice in Pd alloy membranes due to its minimal environmental impact. [ABSTRACT FROM AUTHOR]

This study reports the separation of pure hydrogen (H 2) employing pressure swing adsorption (PSA). The Li-X and Li-hierarchical X (Li–H-X) zeolite were prepared by an ion exchange process. The sorbents were evaluated through several experiments including, breakthrough, empty bed contact time (EBCT), single-bed, and two-bed PSA with different steps. The effect of pressure, purity, and recovery relationship was developed. The high-pressure PSA study was performed at 4, 6, and 10 bar with varying feed flow rates to assess their efficacy in pure H 2 separation using binary gas stream (H 2 /CO 2 , 75/25 vol.%). The breakthrough adsorption capacity of Li–H-X exhibited 3.4 mmol g−1 and 0.212 mmol g−1 of CO 2 and H 2 , respectively. Li–H-X shows ∼8% higher CO 2 sorption capacity than the Li-X sorbent at 1 bar and 300 K due to the large meso-microporous structure of the sorbent. The two-bed PSA purity and recovery were found higher than single-bed PSA. Using two-bed PSA, the Li–H-X achieved a 99.5% of purity, 92.9% of recovery, and 10.4 mL min−1 g−1 of productivity, which was ∼16% higher recovery and productivity than single-bed PSA at a flow rate of 1200 mL min−1 at 6 bar. With increasing the pressure and flow rate, the recovery of Li–H-X was enhanced up to 93.7% with 99.1%–99.9% H 2 purity. The long-term PSA was run using Li–H-X sorbent for 7.5 h with 230 cycles with H 2 purity between 98.5 and 99.5% at 6 bar. Interestingly, the adsorbent shows the scalability of PSA for efficient H 2 separation for a binary mixture of H 2 /CO 2. [Display omitted] • Li–H-X was evaluated using single and two-bed PSA using different conditions. • H 2 purity & recovery of Li–H-X sorbent was higher than Na-X and Li-X adsorbent. • H 2 recovery was higher in two bed PSA compare to sing bed PSA. • PSA cycles were run for a long duration with a marginal decrease in H 2 purity. • Li–H-X was potential sorbent for pure H 2 separtion from binary gas mixture. [ABSTRACT FROM AUTHOR]

• Different fabrication methods and their advantages and disadvantages of COF membranes are reviewed. • The application potential COF membrane in different liquid separations is introduced. • The mechanisms of COF membrane during liquid separation processes are summarized. • The challenges and prospects of the application of COF membrane are presented. Covalent organic frameworks (COFs) are a new kind of crystalline porous materials composed of organic molecules connected by covalent bonds, processes the characteristics of low density, large specific surface area, adjustable pore size and structure, and easy to functionalize, which have been widely used in the field of membrane separation technology. Recently, there are more and more researches focusing on the preparation methods, separation application, and mechanism of COF membranes, which need to be further summarized and compared. In this review, we primarily summarized several conventional preparation methods, such as two-phase interfacial polymerization, in-situ growth on substrate, unidirectional diffusion method, layer-by-layer assembly method, mixed matrix membranes, and so on. The advantages and disadvantages of each method are briefly summarized. The application potential of COF membrane in liquid separation are introduced from four aspects: dyeing wastewater treatment, heavy metal removal, seawater desalination and oil-water separation. Then, the mechanisms including pore structure, hydrophilic/hydrophobic, electrostatic repulsion/attraction and Donnan effect are introduced. For the efficient removal of different kind of pollutions, researchers can select different ligands to construct membranes with specific pore size, hydrophily, salt or organic rejection ability and functional group. The ideas for the design and preparation of COF membranes are introduced. Finally, the future direction and challenges of the next generation of COF membranes in the field of separation are prospected. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper provides an in-depth examination of critical and strategic raw materials (CRMs) and their crucial role in the development of electrolyzer and fuel cell technologies within the hydrogen economy. It methodically analyses a range of electrolyzer technologies, including alkaline, proton-exchange membrane, solid-oxide, anion-exchange membrane, and proton-conducting ceramic systems. Each technology is examined for its specific CRM dependencies, operational characteristics, and the challenges associated with CRM availability and sustainability. The study further extends to hydrogen storage and separation technologies, focusing on the materials employed in high-pressure cylinders, metal hydrides, and hydrogen separation processes, and their CRM implications. A key aspect of this paper is its exploration of the supply and demand dynamics of CRMs, offering a comprehensive view that encompasses both the present sttate and future projections. The aim is to uncover potential supply risks, understand strategies, and identify potential bottlenecks for materials involved in electrolyzer and fuel cell technologies, addressing both current needs and future demands as well as supply. This approach is essential for the strategic planning and sustainable development of the hydrogen sector, emphasizing the importance of CRMs in achieving expanded electrolyzer capacity leading up to 2050. • Analyzes CRMs in hydrogen tech, focusing on electrolyzers and fuel cells. • Explores CRM implications in hydrogen storage and separation. • Investigates CRM supply and demand, identifying risks and strategies. • Highlights the role of CRMs in sustainable hydrogen sector development. [ABSTRACT FROM AUTHOR]

Hydrogen has received great attention as a carbon-free and clean energy source. General industrial processes of hydrogen production involve the separation of gas mixtures to fulfil the purity requirement for most practical applications. Among various separation technologies, membrane separation based on proton-conducting ceramics has been shown to be a very promising method duo to reduced energy consumption and high purity. This review covers the key aspects of hydrogen separation using proton ceramic membranes, including the two main types of hydrogen permeation, namely electrochemical hydrogen pumping based on pure proton conduction, as well as spontaneous hydrogen permeation based on mixed proton-electron conducting membranes. In addition, the challenges facing hydrogen separation technology via proton ceramic membrane and the key issues yet to be solve are summarized. This review aims to provide a reference for the future development and application of this technology. • Systematic review of ceramic hydrogen membranes: proton conduction, separation processes, and key factors. • Detailed overview of electrochemical ceramic hydrogen pump research: materials, electrodes, structures. • Discussion on state-of-the-art results and optimization for hydrogen separation via mixed proton-electron membranes. • Highlighting important, underexplored aspects of proton ceramic membranes for hydrogen separation. [ABSTRACT FROM AUTHOR]

• A diffusion-heat-flow coupling model at extremely low temperatures is established. • Friction and phase separation of 3He-4He mixtures are introduced in the model. • Mechanism of heat and mass transfer in mixing chamber is analyzed. • A temperature of 8.01 mK is obtained in the mixing chamber. • Parameter sensitivity analysis of the mixing chamber is performed. Dilution refrigeration using a 3He-4He mixture as a working medium has gradually become one of the most important methods to obtain millikelvin temperature. At present, the study on dilution refrigeration is mainly aimed at commercializing the whole product. However, the heat and mass transfer characteristics of 3He-4He at extremely low temperatures in the mixing chamber lack systematic study. In this study, a diffusion-thermal-flow coupling model in the mixing chamber is established for the first time in view of the low-temperature characteristics of 3He-4He mixtures. An improved two-fluid model is introduced, considering the finite solubility of 3He in the superfluid 4He and the friction between the components of the mixed working medium. The mechanism of refrigeration and diffusion at extremely low temperatures is analyzed. The refrigeration and mass transfer rates caused by diffusion have almost the same variation trend, and the cooling power of 4.9 μW at 20 mK is obtained. The sensitivity of the heat and mass transfer process to the 4He viscosity coefficient is analyzed. The lowest temperature of 8.01 mK is obtained through parameter adjustment in the mixing chamber. Finally, the cooling capacity is transferred layer by layer from the phase interface to both sides, and it is obviously affected by the inlet, showing a bending trend. The refrigeration capacity of the mixing chamber increases rapidly with the increase of the inlet flow rate when the inlet flow rate varies from 25 μmol/s to 50 μmol/s. [ABSTRACT FROM AUTHOR]

Fruit juices can undergo concentration through traditional means, such as multi-stage vacuum evaporation. However, this method often leads to color degradation, loss of fresh juice flavor, and an undesirable "overcooked" taste due to the thermal process involved. Preserving the nutritional components and delicate sensory properties of fruit juice during the concentration process has proven to be a challenging task in the realm of food processing. To address this challenge, membrane-based separation technology has emerged as a promising alternative for fruit juice concentration. Compared to conventional methods, membrane-based processes offer several advantages, including minimal thermal damage to the product, lower equipment costs, reduced energy consumption, and improved retention of aroma compounds. However, membrane fouling remains a significant drawback in these processes. Recent technological advancements have sought to overcome these limitations by integrating membrane processes with other technologies for concentrated fruit juice production. This study provides a comprehensive discussion and review of the recent progress, developments, and prospects of membrane-based processes in fruit juice concentration. Additionally, a novel approach to achieving sustainable fruit juice concentration is proposed, involving the integration of agricultural irrigation and a dual-cycle forward osmosis process. In this innovative process, food additives containing plant nutrients are employed as the draw solute for both cycles in the forward osmosis process, and the resulting diluted draw solution can be utilized as fertilizer. This approach ensures that all products and by-products are utilized without any detrimental effects on both human health and the environment. [ABSTRACT FROM AUTHOR]

A pressure swing hydrate-membrane coupled separation (PSHMS) process was designed, and process simulation was conducted using a combination of Aspen Plus and Excel. PSHMS achieves continuous, highly efficient, and stable production of qualified gaseous products without thermodynamic promoters of hydrate or circulating working fluids. In hydrogen separation from diesel hydrogenation tail gas, PSHMS exhibits lower energy consumption and higher efficiency compared to hydrate-based separation technologies. Sensitivity analyses of various design parameters within PSHMS were performed through simulation, the results indicate that low temperature, high initial pressure, and high water content are all advantageous for improving separation efficiency. The selection of feed rates needs to be determined comprehensively based on the design parameters. The optimized unit energy consumption of PSHMS is merely 46.41 kJ/mol, significantly lower than the 117.94 kJ/mol of hydrate-based separation technology. • Study of self-designed pressure swing hydrate-membrane coupled method (PSHMS). • The energy consumption of PSHMS is only 40% of that in hydrate-based separation method. • The operational approach of pressure swing separation mitigates hydrate blockage issues in pipelines. • Sensitivity analysis of design parameters in PSHMS was conducted. • Lower temperatures, higher pressures, and increased water content are conducive to effective performance. [ABSTRACT FROM AUTHOR]

The prominence of hydrogen energy has brought membrane separation technology to forefront attention. La 2 Ce 2 O 7 , possessing a fluorite structure, exhibits notable stability in both H 2 O and CO 2 , rendering it a prospective material for membrane separation. The impact of Sr doping on the electrochemical characteristics of La 2 Ce 2 O 7 was systematically investigated. The findings indicate that a minor addition of Sr2+ through doping enhances the electrical conductivity, with the most significant improvement observed in La 2-x Sr x Ce 2 O 7-δ (x = 0, 0.05, 0.15, 0.30) when doped by 0.05. Elevated temperature and increased hydrogen partial pressure on the feed side enhance hydrogen permeability. Hydrogen permeation is predominantly governed by bulk diffusion when the membrane thickness exceeds 0.59 mm, while for thicknesses below 0.49 mm, the process is influenced by both surface and bulk diffusion. Moreover, the doped La 2 Ce 2 O 7 exhibit commendable stability in H 2 O and CO 2 environments. Consequently, La 2 Ce 2 O 7 emerges as a promising candidate for ceramic hydrogen separation membranes. • The impact of Sr doping on the electrochemical characteristics of La 2 Ce 2 O 7. • Sr doping increases the oxygen vacancy concentration and conductivity of La 2 Ce 2 O 7. • Pt–La 1.7 Sr 0.3 Ce 2 O 7-δ exhibits the highest hydrogen permeation flux. • The samples are stable at boiling water and CO 2 atmosphere at 900 °C. [ABSTRACT FROM AUTHOR]

Novel distillation configurations continue to appear in the literature despite the predictions made many decades ago that distillation had attained the status of a mature and stagnant technology needing no further research and development. The driving force for improvement has traditionally been energy conservation, but political decisions related to environmental and sustainability issues have provided additional motivation for improving the efficiencies of chemical and petroleum processes. Since distillation columns require a large fraction of the total energy used in these processes, there is a significant incentive to improve process efficiency. An excellent example of this activity is a paper in which a conventional three-column extractive distillation configuration is compared with a novel two-column process that includes a single decanter. The chemical separation system is a ternary mixture of methanol, water and toluene, which is important in the pharmaceutical industry. The new configuration reduces total annual cost by 50%. The purpose of this paper is to propose a simple modification of the two-column configuration that reduces energy costs by an additional 14% by using two decanters in series operating at different temperatures. • A modified two-column configuration for separating a mixture of methanol, water and toluene is explored. • Using two decanters in series operating at different temperatures saves energy and capital costs. [ABSTRACT FROM AUTHOR]

Pressure swing adsorption(PSA) based gas separation technology is widely applied in chemical industries, especially in hydrogen purification. Its complex mechanism and non-steady state feature restrict the separation performance adjustment and application on efficient gas utilization. Process simulation, machine learning and modelling combined innovating gas management methodology is proposed in this paper to perform accurate gas separation for natural gas based syngas mixture. VB script program is employed to drive Aspen adsorption simulation, and then classical and regression tree(CART), polynomial regression(PNR) and surrogate model are comprehensively used to perform machine learning. Consequently, the coefficient matrix is obtained to quantify the separation performance. This method holds the potential for broader application in refineries and SPCs hybrid hydrogen network, facilitating the comprehensive utilization of hydrogen containing gases. Case study results show this methodology can conserve natural gas and gas productivity by 21.3 %, as well as carbon emission by 8211.6 Nm3/h. This work highlights the promising application of digital twin technology within the chemical industry, showcasing how process simulation, machine learning, and modeling can collectively revolutionize gas management and resource conservation. [Display omitted] • Novel PSA based gas allocation instead of gas separation technology. • Simulation, modelling and machine learning combined gas accommodating methodology. • An insight technology for integration of refinery and SPC. • A novel gas allocation method for zero waste of hydrogen. • An insight application of digital twin technology for gas efficient utilization. [ABSTRACT FROM AUTHOR]

The separation of hydrogen isotopes is a vital step in preparing tritium and deuterium fuels for future fusion power plants. This represents a fundamental challenge to fusion energy since the separation process must be able to handle high throughputs of hydrogen isotopes whilst maintaining a low tritium inventory, because tritium is highly radioactive. There are many possible isotope separation techniques, however none that are currently deployable can meet the demands required. To address this gap, recent developments have improved existing processes and created new high-performance processes including Thermal Cycling Absorption Process (TCAP), electrochemical graphene sieving and absorbative separation based on quantum sieving. In this article, ten of the most promising future hydrogen isotope separation technologies are reviewed, to understand the development route to a process that addresses this key challenge of fusion energy. [Display omitted] • Comprehensive review of new and established isotope separation technology. • Cryogenic distillation, TCAP, PSA, membrane, gas chromatography. • Plasma chemical, thermal diffusion, and laser isotope separation. • Tritium inventory, separation factor and scalability are considered. • Effect of quantum sieving in porous solids and palladium absorption. [ABSTRACT FROM AUTHOR]

Indonesia has natural gas reservoirs with high CO 2 content, such as Natuna and Bojonegoro gas fields. Various technologies have been developed, including cryogenic distillation separation technology suitable for application to gas wells with high CO 2 content. Cryogenic distillation separates CO 2 with high purity according to the operating conditions and the CO 2 dew point. Cryogenic distillation was simulated in this study to determine the purity of the CO 2 and to compare the economic potential of each approach. The highest CO 2 purity using CFZ technology is 98.72% in the Natuna, while the highest purity of CH 4 using Pellegrini Distillation technology is 99.95% in the Bojonegoro. Economically, the Natuna and Bojonegoro estimates using the CFZ technology have a lower total annual cost than the Pelegrini distillation. However, CFZ technology has a lower CO 2 capture cost than Pellegrini Distillation technology, 7.9 USD/tonne CO 2 and 10.26 USD/tonne CO 2. In other words, separation using the CFZ technology is more effective for gas fields with higher CO 2. [Display omitted] • Indonesia has two gas fields with high CO 2 content such as Natuna and Bojonegoro. • Cryogenic technology is most economical for gas field with high CO 2 content. • CFZ concept involves the controlled freezing of CO 2 in a specially designed column. • CO 2 capture cost for CFZ lower than Pellegrini Distillation in both gas fields [ABSTRACT FROM AUTHOR]

• Latest trends and challenges in PVC and copper recovery technologies from thin cables. • Current technologies prioritize copper recovery, PVC recovery is low-priority. • Physical treatments alone cannot achieve high-purity PVC recovery from thin cables. • Combined chemical and physical treatments enable high-purity PVC and copper recovery. • Next-generation solutions for proper management of thin end-of-life cables. This review investigates the latest trends in separation technologies regarding hard-to-recycle thin cables, specifically in the form of end-of-life wire harnesses (WHs). The cables in WHs mainly contain copper (Cu) and poly(vinyl chloride) (PVC), which is commonly used to insulate and sheath cables. This review reveals that most separation technologies prioritize the recovery of Cu and overlook that of PVC. The recovery of high-purity PVC is very important because of its incompatibility with other plastics or Cu during recycling treatments. Through this investigation, we confirm that physical treatments, such as stripping and chopping, are insufficient to recover high-purity PVC from thin cables. Instead, a combination of chemical (e.g., swelling of PVC insulation or sheathing of cables under a suitable solvent) and physical (e.g., ball or rod milling and mechanical agitation of swollen cables) treatments can be used to achieve the recovery of high-purity PVC and Cu both for recycling. We believe that recovering metals and plastics from end-of-life cables is vital for sustainable waste management, offering several environmental and economic benefits. [ABSTRACT FROM AUTHOR]

Deuterium or tritium, which are rare isotopologues of hydrogen, are in high demand across various industries; thus it is crucial to develop a separation technology for hydrogen isotopologues that is both efficient and cost-effective. However, conventional separation methods like 20 K cryogenic distillation have low separation performance (separation factor less than 1.5) and require a significant amount of energy due to their nearly identical physicochemical attributes. And thus, there has been an effort to find a novel separation strategy. In pursuit of this goal, researchers have explored crystalline porous materials utilizing the recently highlighted kinetic quantum sieving (KQS) and chemical affinity quantum sieving (CAQS) techniques. In this context, we will focus on zeolites, which are considered the most widely available crystalline porous material. They are known for exhibiting high thermal and chemical stability, as well as longevity and reusability, making them superior to other porous materials like Metal-Organic Frameworks (MOF). The focus will be on previous studies conducted on zeolites for hydrogen isotopologues separation, with specific emphasis on KQS and CAQS. It was discovered that these studies were mainly limited to certain types of typical zeolites, such as CHA and MFI. Additionally, the mechanisms used were biased toward CAQS due to the presence of metal cations in most zeolites. Furthermore, the previous research did not possess an enough comprehensive understanding of the performance of zeolites. Therefore, this mini-review aims to outline effective strategies that can overcome these limitations and achieve breakthroughs in hydrogen isotopologues separation, leading to commercialization and scientific advancements. • H 2 isotope separation technology is paid significant attention by various industry. • Zeolites excel in the industry due to durability, stability, and reusability. • H 2 isotope separation using zeolite via kinetics and affinity quantum sieving. • Report strategies provide H 2 isotope commercialization, driving scientific progress. [ABSTRACT FROM AUTHOR]

Isopropyl alcohol (IPA) and diisopropyl ether (DIPE) are widely used as biofuel additives in fuel processing. When IPA is produced by propylene hydration, a by-product IPA and DIPE is made. Since the existence of azeotropic point formed between IPA and DIPE, the separation of the azeotrope is achieved using special distillation technologies in industry, which requires high energy consumption. Liquid-liquid extraction was used to separate the mixture due to its energy saving in this work. Three imidazolium-based ionic liquids (ILs) 1-butyl-3-methylimidazolium thiocyanate ([BMIM]SCN), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM]NTf 2) and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF 4) were synthesized as the extractants. The influence of extraction time, extraction temperature, mass ratio of mixture (IPA + DIPE) to ILs and the initial content of IPA in the mixture (IPA + DIPE) on the extraction performance of ILs were studied. The optimal extraction conditions were determined using the response surface method (RSM). The results showed that the IL [BMIM]SCN had better extraction capacity for separation of the mixture (IPA + DIPE). The interactions between molecules were investigated by quantum chemical calculations. Finally, a conceptual separation process is designed to separate the mixture, which can provide a helpful technology to purify the biofuel additives. • Three ILs [BMIM]SCN, [BMIM]NTf 2 and [BMIM]BF 4 were synthesized as extractants to separate mixture (IPA + DIPE). • The extraction performance of the ILs was assessed and the optimal conditions were determined by RSM. • The interactions between IPA and the ILs were analyzed by quantum chemical calculations. • A separation process for purification of IPA and DIPE is proposed with [BMIM]SCN as the extractant. [ABSTRACT FROM AUTHOR]

Melt crystallization is considered a sustainable method for chemical separation and purification. In comparison to static melt crystallization, suspension melt crystallization offers significant advantages in terms of continuous operation and scalability. Understanding the principles of subcooling and impurity inclusion is crucial for designing effective suspension melt crystallization processes. This review focuses on the advancements made in suspension melt crystallization techniques over the past two decades, specifically in process modeling, equipment development, and applications. The review places particular emphasis on kinetic modeling of crystallization and provides an overview of equipment advancements and process intensification strategies for suspension melt crystallization. Additionally, by comparing its applications in traditional chemical industries as well as water systems (such as food processing and water purification), this review discusses both the distinctions and connections between suspension melt crystallization technology with other separation and purification methods. Finally, future prospects for the development of suspension melt crystallization technology are presented. • The kinetic advantages of Suspension Melt Crystallization (SMC) are summarized. • Emphasis is placed on equipment integration for the development of SMC technology. • Process intensification is highlighted for the industrialization of SMC. • The coupling of SMC with various separation and refining technologies is discussed. [ABSTRACT FROM AUTHOR]

Various industrial fields use gas-liquid separation, but due to the variety of gas-liquid separation technologies, no comprehensive review has been conducted. This paper systematically reviews the separation mechanism, application ranges, research status, and development prospects of various separation techniques. The challenges associated with each gas-liquid separation technology are presented. This review indicates that future research should focus on the droplet-droplet and droplet-gas interaction mechanisms and the formation and breakup mechanisms of liquid films. Future experimental efforts should focus on investigating gas-liquid two-phase flow fields including droplet size distribution, phase distribution, and velocity distribution. A promising development direction is to combine several gas-liquid separation technologies to expand their range of applications. An increased knowledge of the relationship between the flow field and separation performance would guide the standardized design of the gas-liquid separators. [Display omitted] • The technical and application state of gas-liquid separation is systematically reviewed. • Phase separation laws for various separation technologies are summarized. • A promising development exists in combining a variety of gas-liquid separation technologies. • A detailed understanding of the relationship between the flow field and separation performance is essential. [ABSTRACT FROM AUTHOR]

Low gravity fluid management is key to a variety of spaceflight applications, from life support aboard the International Space Station to propellant management in satellite tanks. Capillary devices are traditionally employed to position fluids in a microgravity environment, but they fail to induce effective phase separation in the conformal tank geometries and saturated two-phase propellants adopted in modern CubeSat propulsion. In order to meet the stringent requirements of future small satellite missions, this paper explores the application of capillary, magnetic positive positioning, thermal, and dielectrophoretic fluid management devices to conformal propellant tanks. The electromagnetic and capillary devices rely upon body and surface forces, respectively, while the proposed thermal approach exploits phase change in saturated liquid–gas mixtures to position the fluid. Each concept is evaluated based on its ability to reorient the propellant and maintain its position during operation, as well as the resulting volume, mass, and power requirements. Ultimately, thermomagnetic and thermodielectrophoretic devices are deemed to be best suited for the case under analysis because of their low size, weight, and power demand in combination with their reliability and performance. These new systems offer a novel and robust solution to small satellite propellant management, a key enabling technology for the future of maneuverable CubeSats. • Capillary PMDs cannot ensure phase separation in saturated mixtures. • Electromagnetic devices can maintain fluid position in microgravity. • Thermoelectromagnetic PMDs offer improved performance with decreased mass and volume. [ABSTRACT FROM AUTHOR]

The process of membrane gas separation is a technique of increasing interest in industrial applications. In many cases, the membrane gas separation process can replace or support commonly used technologies for gas mixtures separation, such as adsorption, absorption or cryogenic distillation. One of the areas in which the research on the development and implementation of new types of membranes is particularly intensive is the technology of CO2 removal from mixtures containing also CH4 or N2. The need to extract CO2 from these mixtures results from economic, legal, ecological and technological reasons. A solution that can improve the process properties of membranes is the development of heterogeneous membranes. Heterogeneous membranes are structures consisting of a polymeric continuous phase and an organic or inorganic dispersed phase. The presence of additives can improve both the permeability of the membrane and its selectivity, as well as the mechanical properties. However, in addition to developing a new material and examining its properties, it is also necessary to propose a method for manufacturing membranes from these materials on an industrial scale and to determine their process properties based on tests on gas mixtures. For this purpose, heterogeneous capillary membranes obtained by dip coating method were developed. PEBAX® 2533 copolymer and additives such as SiO2, zeolitic imidazolate frameworks (ZIF-8) or PSS-octaphenyl substituted (POSS-Ph) were used to produce them. The permeability and selectivity of the developed membranes were determined on the basis of tests using pure gases (CH4, CO2 and N2), as well as gas mixtures (CO2/CH4 and CO2/N2). The process conditions used in the research, that is, feed pressure and temperature, were determined on the basis of the authors' previous research [1] and mathematical-statistical analysis. On the basis of the conducted tests, the usefulness of the produced composite capillary membranes for conducting the process of separating gas mixtures in which CO2 is one of the components has been proven. [ABSTRACT FROM AUTHOR]

Membrane separation technology is widely used in the treatment of dye wastewater because of its low cost, high separation efficiency, simple operation and no secondary pollution. In this study, a series of blend cellulose acetate (CA) membranes with different compositions were prepared by blending a polycationic liquid synthesized in laboratory with CA. The membranes were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy analysis and the surface properties including the water contact angle, mechanical strength, pure water flux, pore size and zeta potentials were also tested. The hydrophilicity of the membrane was improved by blending more additive. Compared with pure CA membrane, the surface zeta potential value of the modified membrane increased. The maximum pure water flux of the modified membranes was 32.51 L/m²⋅h. In the experiment of filtering two cationic dyes (acridine yellow hydrochloride and Rhodamine B) with different molecular weights, it is found that the blend modified membrane with optimal performance showed better antifouling performance and higher rejection rate, the flux recovery rates of acridine hydrochloride yellow and Rhodamine B were 93.94% and 87.47%, and the rejection rates were 87% and 76.1%, respectively. [ABSTRACT FROM AUTHOR]

Dividing-wall column (DWC) is a promising thermally coupled distillation technology for separating multicomponent mixtures. However, the difficulty of controlling vapor split ratio in DWC affects its energy consumption and so limits its wider application in industrial practice. The liquid-only side-stream distillation (LSD) process not only eliminates the vapor split in DWC but also shows comparable economic and thermodynamic efficiency with DWC. This study systematically optimizes and compares the economic performance of DWC and double LSD (DLSD) process for separating ethanol-propanol-butanol ternary mixture, and then analyzes exergy flows in these two processes in detail. Results indicate that TAC of DLSD process is 11.47% lower than that of DWC process, and exergy efficiency of DLSD and DWC processes is 10.81% and 8.57%, respectively. However, both processes exhibit similar exergy destruction in condensers, columns, coolers and reboilers. • Double liquid-only side-stream distillation (DLSD) and dividing-wall column (DWC) are presented and optimized. • Both economic assessment and exergy analysis of DLSD and DWC are carried out. • DLSD has lower annual total cost and higher efficiency than DWC. • DWC and DLSD exhibit similar exergy destruction distributions in columns and heat exchangers. [ABSTRACT FROM AUTHOR]

Molybdenum sulfide (MoS 2) materials adapted into membranes have demonstrated potential for different areas dealing with molecular separations. For instance, MoS 2 -based membranes have been proposed for distinct environmental applications, such as water treatment, seawater desalination, gas separation, and solvent separation. Emergently, such membranes have been ultimately investigated for energy-relevant gas separation mixtures, such as CO 2 separation, H 2 purification, and bioethanol upgrading, among others. Therefore, this review elucidates the latest research (over the last three years) on MoS 2 -based membranes facing previous approaches. Firstly, a brief introduction to the physiochemical properties of MoS 2 -based materials. Secondly, a particular emphasis has been devoted to fabrication procedures and their effects on molecular separation in membrane processes, highlighting the most relevant outcomes and the transport mechanism reported by the research community in water treatment and purification, gas separation, and pervaporation. Finally, an analysis is conducted on the separation and stability mechanisms associated with membranes consisting of layer-stacked MoS 2. This research endeavor progressions in MoS 2 -based membranes, consequently fostering the advancement of further membranes derived from two-dimensional materials. These membranes exhibit potential for improving efficiency and mitigating the energy consumption linked to water treatment and purification processes. [Display omitted] • Composite membranes containing MoS2 exhibit potential for different environmental energy-relevant separations. • The hexagonal lattice structure of MoS2 allows the fabrication of nanoscale thickness with tunable interlayer spacing. • MoS2 membranes proved exceptional molecular sieving effect in seawater desalination. • Emerging applications in CO2 and H2 separation have been initiated over the last two years. [ABSTRACT FROM AUTHOR]

An intelligent optimization of multistage gas permeation layouts is required to achieve high product gas purities and high product recoveries at the same time in gas separation technologies. In this work, a superstructure-based mathematical model for the optimization of CO 2 removal in three applications including post-combustion CO 2 capture, natural gas sweetening and biogas upgrading is designed. A typical polymeric membrane prepared within the BIOCOMEM project, with high CO 2 permeance, CO 2 /N 2 selectivity of 25, and CO 2 /CH 4 selectivity of 7.9 is studied to assess the potential of this membrane at a real industrial scale. Using a superstructure-based model, operating conditions, driving force distribution along each membrane stage, the use of feed compression and/or permeate vacuum, the number of stages and recycle options are simultaneously optimized. The techno-economic analysis of all three applications is then carried out and the most promising membrane-based process configuration was chosen. The multi-stage membrane process is investigated in terms of capture cost, energy consumption, and membrane area. The results revealed that high purity and recovery at a minimum cost could be achieved by the three-stage process in post-combustion CO 2 capture and natural gas while in biogas upgrading the two-stage configuration exhibited the best performance. It was found that a reduction in capture cost to around 42 €/tCO 2 is possible in post-combustion CO 2 capture if membranes with a selectivity of 50 and the same permeation flow are developed. [Display omitted] • A superstructure-based optimization approach for gas separation was designed. • Superstructure applied to CO 2 removal from flue gas, natural gas and biogas upgrading. • Techno-economic feasibility analysis on membrane system for CO 2 separation. • Approach was investigated in terms of cost, membrane area and power consumption. • The power consumption and capture cost are a strong function of CO 2 purity. [ABSTRACT FROM AUTHOR]

Nowadays, membrane has played an important role in wastewater treatment. However, high membrane cost and membrane fouling has hindered the developing of conventional membrane separation technology. With low-cost supporting membrane and easy operation, dynamic membrane (DM) technology presents a new route for pollutants separation in wastewater treatment. Similar pollutants removal and high separation efficiency made it more suitable for application in wastewater pretreatment and sludge separation. To have a full understanding of recent development of membrane separation technology, microfiltration, ultrafiltration, nanofiltration, and dynamic membrane filtration were briefly introduced and compared in this study. The filtration and pollutants removal performance in membrane bioreactor and dynamic membrane bioreactor were also evaluated. Besides, future perspectives of membrane separation technology with membrane fouling control, membrane cost and maintenance were presented for better application of membrane technology. Overall, DM technology indicates one potential developing direction of membrane separation technology in wastewater treatment. [ABSTRACT FROM AUTHOR]

Heat-integrated distillation columns (HIDiC) are sustainable technologies whose optimized designs may reduce up 80% the energy consumption, cooling water and CO 2 emissions regard to the traditional columns. This paper shows a novel approach to design and optimize HIDiC columns using Aspen Plus and a stochastic optimization algorithm. This approach was designed to deal with the convergence problems in order to improve the search for the best solutions but also keep a continuous optimization process. The performance of the approach was evidenced through the optimization of the HIDiC columns used to split four close-boiling binary mixtures. Results showed that the design and optimization of these columns was successfully tackled by the approach implemented. As a result, the approach enabled to reduce convergence problems, keep a continuous optimization process and improve the quality of the solutions found. This fact demonstrates that the approach performed an adequate handling of purity specs and temperature driving forces, which were defined as constraints of the optimization problem. Based on the performance determined, this approach may be adapted and used as an approximated short-cut method to design and optimize other binary HIDiC columns. However, through an adequate adaptation, this approach may be extended to design and optimize HIDiC columns for separating ternary mixtures. [Display omitted] • This novel approach was implemented to design and optimize HIDiC columns. • The approach relates simultaneously constraints and optimization variables. • The approach was validated using design specs defined in Aspen Plus. • The approach reduced convergence problems in the optimization. • The approach preserved a continuous optimization process. [ABSTRACT FROM AUTHOR]

The ultrafiltration/diafiltration (UF/DE) process is a crucial step in the canola protein isolation process from rapeseed meal. The process involves using a multi-stage membrane system to separate components of the mixture. As diafiltration dilutes the feed stream in the ultrafiltration system, a large amount of diafiltration water is required. Reducing the diafiltrate for sustainability reasons can be done by carefully selecting process variables or using recycle streams. However, finding the optimum process variables can be a meticulous process if performed experimentally or via trial and error. In this study, we performed an optimization using a mechanistic model integrated with a genetic algorithm to aid in finding an optimum combination of process variables. The mechanistic ultrafiltration model was derived by taking into account transport phenomena within the filtration system. Parameters were characterized experimentally in term of viscosity coefficient, membrane resistance, cake porosity, aggregate diameter equivalent, and material compressibility factors. Using the mechanistic model-based optimization in combination with actual experimental values, the performance of a fourstage UF/DF system could already be improved despite fixing the configuration, albeit at the cost of a reduction in purity. Further improvement could be achieved by using recycle streams. The optimized system achieved a diafiltrate reduction of up to 79%, an increase of purity of up to 31%, and an increase of dry matter content of up to 18%, while maintaining the product purity of the reference set-up. [ABSTRACT FROM AUTHOR]

Eggs are a compelling source of bioactive compounds. Membrane separation is a green technology that allow components to be obtained while preserving their biological activity. The objective of this study was to assess the application of membrane separation technology to egg products. Whole egg plasma, egg yolk plasma and egg white were tangential flow filtrated evaluating the effect of the pore size and membrane materials. Transmission of dry matter and proteins from feed to filtrate was noticed in all the processes. Nevertheless, cholesterol and carotenoids were not detected at filtrates from 750 kDa to 0.2 wn when mixed ester or polyethersulfone were the membrane materials. The interactions between egg yolk and egg white components difficult the separation. Cholesterol was part of low-density lipoproteins. These lipoproteins together with carotenoids were filtrated with modified polyethersulfone at a minimum pore size of 0.2 pm. High uncertainty was obtained due to low-density lipoproteins aggregation. Three kinds of aggregates can justify these results: low-density lipoproteins aggregated themselves, low-density lipoproteins bound to ovomucin and other smaller egg white proteins (< 750 kDa), and low-density lipoproteins bound only to smaller egg white proteins. The detected chelate effect of egg white proteins could be important in uiuo, Therefore, research should be led to assess the influence of cooking method and digestion of the different egg components on the bioaccessibility of nutrients and the generation of bioactive peptides. Moreover, the filtration processes analysed herein may be useful techniques for liquid food matrix studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electromagnetic induction technology was examined to harvest cathode materials. • High-purity of recovered electrode materials and Al foils were achieved. • A synergistic separation mechanism of cathode materials and Al was proposed. The separation of electrode materials from current collectors plays a significant role in determining the leaching efficiency of different metals from spent lithium-ion batteries (LIBs). In the presented research, a highly efficient, environmentally sustainable, and cost-effective cathode materials separation strategy was proposed for spent LiFePO 4 batteries. Based on the difference in the thermal expansion coefficient of the binder and aluminum foil, the electromagnetic induction system was examined to harvest cathode materials for the first time, which could provide a high heating rate to erase the mechanical interlocking force between Al foil and coated material, and breaking the chemical bond or Van der Waals forces of the binder. The process avoids the usage of any chemicals such as acids and alkalis, thus eliminating the emission of wastewater. Our system shows ultra-fast separation (3 min) and achieves high-purity of recovered electrode materials and Al foils (99.6% and 99.2%). Furthermore, the morphology and crystalline structure of delaminated electrode materials remain almost the same compared with the pristine materials, which provides a previously unexplored technology to realize sustainable spent battery recycling. [ABSTRACT FROM AUTHOR]

Protein-derived components including proteins and peptides are important to human nutrition and health because they are a source of energy and essential nutrients. Moreover, some of them exhibit bioactive properties such as antioxidant, antimicrobial, anticancer, and anti-hypertension activities. However, the poor stability, unpleasant flavor, and difficulty in separating protein-derived components currently limits their application as functional ingredients in many functional foods, supplements, and pharmaceuticals. Cyclodextrins (CDs) can overcome some of the limitations of protein-derived components by forming host-guest inclusion complexes with specific amino acid moieties. The formation, structure, and properties of these complexes can be characterized using various computational and experimental approaches. The properties of host-guest complexes can be modulated by modifying the CDs, which can extend or improve their functionality. Key findings and conclusions : The host-guest properties of CDs can be used to develop detection and separation technologies for protein-derived components. These properties can also be used to encapsulate protein-derived components in CD-based delivery systems, thereby improving their water-dispersibility, stability, flavor profile, and functional attributes. Overall, CDs have great potential for the production, application, and characterization of protein-derived components in functional foods. However, further research is required to evaluate their application in real food products and to establish their safety profiles and efficacy using in vivo methods. [Display omitted] • CDs can form host-guest inclusion complexes with protein-derived components. • CDs can improve the flavor, texture, and bioactivity of protein-based foods. • CDs are effective in recognizing and separating proteins and peptides. • CDs facilitate the development of delivery systems for proteins/peptides. [ABSTRACT FROM AUTHOR]

Ti 3 C 2 T x -based modified separation materials are widely used in the field of wastewater separation, but most of them have poor fluxes. Here, grafting of l -cysteine and l -histidine onto polydopamine-pretreated Ti 3 C 2 T x surface was used to obtain amino acid-modified Ti 3 C 2 T x (L-CPT and L-HPT), respectively, by covalent and non-covalent bonds under mild conditions, enriching variety and number of hydrophilic groups on the Ti 3 C 2 T x surface. Polyurethane sponge (PU) coated with L-CPT and L-HPT (L-CPTPU and L-HPTPU) exhibit excellent underwater oleophobicity and show impressive separation efficiency (>99.4%) for various oil-water mixtures. Especially, L-CPTPU and L-HPTPU achieved high-throughput separation for cyclohexane-water mixtures with maximum permeation fluxes of 220,319 and 222,197 L m-2 h-1, respectively, and had excellent resistance to corrosive media. Besides, polyamide membranes modified with L-CPT and L-HPT (L-CPTPA and L-HPTPA) form abundant permeation channels, achieving high-efficiency separation for toluene in water emulsion with separation efficiency greater than 99.1%. In addition, L-CPTPA and L-HPTPA exhibited remarkable rejection (>99.1%) and high permeability (>1100 L m-2 h-1 bar-1) for 20 mg L-1 malachite green solution. Therefore, the amino acid-modified Ti 3 C 2 T x can functionally modify PU and PA substrates toseparate oily wastewater and dye wastewater, respectively. [ABSTRACT FROM AUTHOR]

The separation of azeotropic mixtures is often energy intensive, thus process intensification (PI) becomes an attractive route to enhance energy efficiency. Two of the most commonly used separation intensifications are dividing wall columns and hybrid distillation-membrane processes. In this work, three typical hybrid distillation structures, distillation followed by pervaporation (D-P), pervaporation followed by distillation (P-D), and distillation followed by pervaporation then by distillation (D-P-D), are considered and compared with a hybrid dividing wall column (H-DWC) structure, which is a highly integrated process combining a dividing wall column and a pervaporation membrane network. The four structures are compared by both single-objective and multi-objective optimisation. It is shown that the D-P-D and H-DWC structures require significantly lower total annualized costs than the other two designs due to requiring smaller membrane area, as these two structures use the membrane only to help the mixture composition cross the azeotropic point. [Display omitted] • Method for optimisation of hybrid distillation-pervaporation processes. • Design and optimisation of hybrid dividing wall column (H-DWC). • Assessment of performance based on single- and multi-objective optimisation. [ABSTRACT FROM AUTHOR]

Sulfur hexafluoride (SF 6) has extremely high global warming potential and must be separated and recovered to avoid its emission into the atmosphere. Hydrate-based gas separation, which uses only water as the separation medium and has low environmental impact, is expected to become a new separation and recovery technology for SF 6. However, this technique has the drawback that hydrate particles in the slurry can block equipment piping. Therefore, this study investigated the flow pattern and rheological properties of SF 6 hydrate slurry using a loop-tube flow apparatus. SF6 hydrate slurry was observed to have three flow patterns as the flow velocity varied: homogeneous flow, heterogeneous flow, and moving-bed flow. We developed experimental relationships based on the Turian–Yuan equation to estimate the flow velocities at which the flow patterns change. These experimental equations were able to predict these velocities within an error of approximately 10%. The rheological properties of SF 6 hydrate slurry were found to exhibit Newtonian tendency at low solid fractions and pseudoplastic tendency at high solid fractions. The relative viscosity of the slurry could be estimated within 25% error using the Krieger–Dougherty model. • Flow pattern and rheological properties of SF 6 hydrate slurries were assessed. • Experimental equations are proposed to predict flow pattern changes. • SF 6 hydrate slurry showed pseudoplasticity under high solid fractions. • Relative viscosity to water was estimated using the Krieger–Dougherty model. [ABSTRACT FROM AUTHOR]

Electric dehydration technology has gained lots of attention as an oil-water separation technology that has only been around for a short time. Many research scholars have studied the laws of droplet motion in electric fields. However, previous research on the droplet motion law in a non-uniform electric field has only focused on the single droplet, ignoring the dipole-dipole interaction between droplets, which plays an important role in the droplet coalescence process. In this paper, the motion of droplet pairs in a non-uniform matrix electric field is studied by means of theoretical analysis and numerical simulation. A mathematical model of the migration velocity and coalescence time of droplet pairs was established. The results show that the migration velocity of droplet pairs under dielectrophoresis and dipole-dipole interactions is significantly greater than that of single droplets and that the droplet velocity is related to the electric field strength, continuous phase viscosity, droplet diameter, and droplet pair center distance. This study increases our understanding of droplet electrocoalescence kinetics, enriches the electrocoalescence mechanism of droplets under non-uniform electric fields, and provides a basis for the design of subsequent electrodehydration equipment. [Display omitted] • Theoretical and numerical analysis of droplet pair motion law under non-uniform electric field. • The expressions of migration velocity and coalescence time of droplet pair are proposed. • The mechanism of droplet electrocoalescence under non-uniform electric field is supplemented. [ABSTRACT FROM AUTHOR]

Effluents from industries include high levels of toxic heavy metals and are considered to be one of the serious sources of water pollution. Galvanizing, electroplating, tannery, textile, and dye industries are the major sources of heavy metal contaminants. To protect the environment from the toxic effects of the effluents, it is highly necessary to treat this industrial effluent before discharging it into the water bodies. This paper focuses on the critical analysis of conventional separation processes such as adsorption, chemical precipitation, coagulation and flocculation, and membrane separation processes for the separation and recovery of zinc from wastewater. This paper deals with the analysis of effective separation technologies for the removal of zinc from industrial effluent. The advantages and limitations of the technologies for the separation and recovery of zinc have been compared and critically analyzed. This paper also provides the outline of hybrid membrane technology in the ultrafiltration process known as complexation-enhanced ultrafiltration for the separation and recovery of zinc from the aqueous stream. [ABSTRACT FROM AUTHOR]

For an environmentally friendly and economical separation process of ethanol from n-hexane which is hard to handle due to the azeotrope, the liquid-liquid extraction was carried out by using choline chloride (ChCl) based deep eutectic solvents (DESs) in different molar ratios with 1,4-butanediol: DES1 (ChCl:1,4-butanediol=1:3), DES2 (ChCl:1,4-butanediol=1:4), and DES3 (ChCl:1,4-butanediol=1:5). The liquid-liquid phase equilibrium was performed on the n-Hexane (1) + Ethanol (2) + DES (3) systems at 298.15 K and atmospheric pressure. The binodal curve is determined by using the turbidity method. The various physico-chemical properties such as refractive index, viscosity, and density were measured for compositions in the binodal point. The equilibrium compositions of liquid-liquid phase equilibrium were determined from the refractive index value at the binodal points, and were predicted by COSMO-SAC model. The miscibility area predicted by COSMO-SAC model became larger as the molar ratio of 1,4-butanediol in DES increased, that is, DES3 shows the most miscible area. While in the experimental results, the miscibility depending on DES-type does not show a large difference. The experimental values for PI shows the order of DES2 (ChCl:1,4-butanediol=1:4)> DES1 (ChCl:1,4-butanediol=1:3)> DES3 (ChCl:1,4-butanediol=1:5) at less 3 wt% concentration of ethanol, but at higher concentration range (>3 wt%) DES3 shows the best value. Both of DES2 and DES3 are profitable to adopt in the extraction process of ethanol from n-hexane owing to the high performance index, high distribution coefficient, and high selectivity. The experimental results show the possibility of DESs as an alternative to ionic liquids in the separation of azeotropic mixtures, taking into account the properties of DES such as low price, uncomplicated manufacturing methods, environmentally friendly, and low toxicity. [Display omitted] • LLE was carried out by using different three ChCl-based DESs. • COSMO-SAC model described well the LLE phase behavior • DES (ChCl:1,4-butanediol=1:4) shows a high performance index. • Three DESs show much higher selectivity compared to ionic liquids. [ABSTRACT FROM AUTHOR]

With the ever-growing electromagnetic (EM) wave pollution and the rising demand of flexible absorbing materials pasted onto the surfaces of different geometric surfaces, it is urgent to develop high-efficiency EM wave absorption films with good flexibility and mechanical strength. Traditional processing methods endow the film superior features that can be adapted to targeted geometric surfaces and complex conditions, however, the durability is not satisfactory. Confronted with the tough problem, in this work, optimized thermally assisted homogeneous separation technology was proposed to fabricate the thermoplastic elastomer-based magnetic/dielectric two-phase mixed EM wave absorption films, which can achieve good flexibility, machinability, mechanical strength, as well as excellent EM wave absorption performances due to the uniform filling of elastoplastic skeletons and chain-bridge effect between chains and particles. Benefitting from these merits, the as-prepared films exhibit good flexibility and fine mechanical properties, like good deformability (300% of the deformation compared to its original length) and low elastic coefficient (323.8 Pa). Moreover, good EM wave absorption performances can also be balanced, for example, broad effective bandwidth (>14 GHz) and tunable frequency response from high frequency to low frequency. In all, this work opens up a new pathway to realize the integration of strong EM response, good flexibility, and fine mechanical properties, and the obtained films exhibit great potentials as flexible EM wave absorption materials that can be pasted on or peeled off the targeted surfaces at any time. [Display omitted] [ABSTRACT FROM AUTHOR]

Membrane-based gas separation (GS) has emerged as a competitive separation technology for industrial gas separation applications due to its simpler operation and cost-effective approach. This paper reviews the computational parameters and boundary conditions involved in model simulations, including the general assumptions made for the gas separation process. The transport mechanisms used for dense and porous gas separation membranes are discussed, followed by verification studies of CFD models. The impacts of different operation parameters, such as the temperature, pressure ratio, variation in hydrodynamics, and membrane selectivity, on membrane performance are evaluated in terms of gas permeation flux and concentration polarisation (CP). This review also describes the effect of obstacles (feed spacers) and various unsteady flow approaches for improving performance. Finally, challenges and future perspectives in CFD simulation involving membrane gas separation are provided. [Display omitted] • CFD modelling for membrane gas separation is reviewed. • Methodology of CFD modelling for dense and porous membranes is given. • Effects of different operating conditions are discussed. • Challenges and future perspectives on gas membrane CFD modelling are provided. [ABSTRACT FROM AUTHOR]

In this paper the dynamic performance of Heat-Integrated Distillation Columns (HIDiC) is presented. The dynamic performance was determined for the optimal HIDiC designs optimized previously using a constrained Boltzmann-based estimation of distribution algorithm. Eight close-boiling mixtures, covering a range of relative volatility (α) from 1.12 to 2.4, were used as case studies. The dynamic behavior was obtained under open and closed-loop process analysis. The results obtained showed that the HIDiC columns undergo worse dynamic performance than their equivalent traditional columns for all case studies. Furthermore, it was notorious that the difference in the dynamic behavior of both configurations kept a relatively uniform trend for most systems. However, a marked difference in the dynamic properties was determined for the mixture close to azeotropic behavior, which experienced a considerably larger control effort. Thus, the novel findings disclosed in this paper show that, although the HIDiC sequences experienced worse dynamics than the conventional columns, the HIDiC configurations reached a stable dynamic behavior for all the range of α of the mixtures under study. Nevertheless, high control difficulties were particularly determined for the HIDiC configuration used to separate the mixture with α close to unity (mixture of xylenes), which in fact is the HIDiC sequence with the best energetic and economic benefits. Hence, the energetic and economic potential of the HIDiC columns is not limited by the dynamic behavior for most case studies analyzed, at least in theoretical terms. However, such potential might be particularly reduced or unharnessed in the separation of the mixture with α near the azeotropic behavior due to the dynamics of the HIDiC column for this separation. So, the findings presented in this paper allow to infer that sequential or simultaneous dynamic studies must be achieved along with the optimization of the HIDiC columns to determine the integral performance (energetic, economic and dynamic) of these configurations. [Display omitted] • Dynamic performance of Heat Integrated Distillation Columns is presented. • Eight low relative volatility equimolar mixtures were examined. • Dynamic performance was determined using open and closed-loop process analysis. • HIDiC columns showed worse dynamic performance than the conventional columns. • The mixture with lowest relative volatility showed the worst dynamic performance. [ABSTRACT FROM AUTHOR]

In order to effectively solve the problem of low separation efficiency of respiratory dust in coal mine, a multi-factor orthogonal experiment was designed for the virtual impact separation device. A coupled airflow-dust migration model for describing the interior of the separator device was established based on the Euler-Lagrange method, and the 3D structure materializing of the separator was realized by accurate 3D printing technology. The maximum deviation of the separation efficiency between the experimental results and the simulation results is 5.85%. Through range analysis, the importance degree of each factor affecting the separation efficiency is determined as follows: nozzle diameter (20.31) > inlet section diameter (18.02) > distance between nozzle and large particle collecting cavity (14.85) > inlet length (10.66) > large particle collecting cavity diameter (10.04) > strong current sampling flow rate (7.84); The better separation scheme is found and the separation efficiency of dust with particle size of 1 µm∼7 µm is 91.75%, 90.75%, 78.61%, 68.85%, 58.14%, 34.12%, 12.41%, respectively. The research results provide theoretical guidance for the development and application of virtual impact separation technology. [Display omitted] • A airflow-dust migration model for the interior of the separator was established. • The accuracy of the migration model was verified by the separation experiment. • The importance degree of each factor affecting the separation was obtained. • The separation efficiency of the better separation scheme of dust were determined. [ABSTRACT FROM AUTHOR]

A schematic diagram illustrates the preparation of a CD-based PIL membrane and the treatment of oily wastewater. The cross-linked PILs network coatings with CD skeleton have succeeded in constructing on both the inner and surface of the PVDF membrane via a facile one-step photopolymerization. We believe that such green, sustainable, and multi-functional advanced membrane materials facilitate industrial production and separation of oil–water mixtures. The CD-based PIL composite membrane endows it to promote robust anti-oil fouling and self-cleaning properties, durability as well as significant separation performance and recyclability. [Display omitted] Membrane fouling remains a persistent and arduous challenge in the industrial treatment of different surfactants-stabilized oily wastewater. Constructing a robust antifouling and sustainable hydration coating on the membrane surface to efficiently repel oils or surfactants is a critical requirement. Herein, cyclodextrin-based poly(ionic liquid)s (PILs) coatings are cross-linked via the co-deposition on poly(vinylidene fluoride) (PVDF) of quaternized heptkis(6-deoxy-6-vinylimidazolium)-β-cyclodextrin (CD-Vi) derivatives as skeleton and acrylic acid (AA) monomers, and following one-step free radical photopolymerization. Combining with the strong hydration of the CD-based PILs coating, the resultant membrane exhibits fabulous superhydrophilicity and underwater superoleophobicity, oil repulsion, and self-cleaning capability. It demonstrates robust mechanical durability and chemical stability in harsh environments without losing its superhydrophilicity. Besides, the PIL-CD/AA coating can separate various surfactant-free and different surfactants (cationic CTAB, anionic SDS, and nonionic TWEEN 80) stabilized oil / water emulsions. During the long-term cycle operations, it also realizes stable recyclability with a series of permeation fluxes as high as removal efficiencies (>99.6 %) after 20 cycles for surfactant-free cyclohexane-in-water emulsion and 10 cycles for CTAB-stabilized isooctane-in-water emulsion. [ABSTRACT FROM AUTHOR]