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Liquid–liquid phase separation in diverse manufacturing and biological contexts often occurs in the presence of aggregated particles or complex-shaped structures that do not actively participate in the phase separation process, but these "background" structures can serve to direct the macroscale phase separation morphology by their local symmetry-breaking presence. We perform Cahn–Hilliard phase-field simulations in two dimensions to investigate the morphological evolution, wetting, and domain growth phenomena during the phase separation of a binary mixture in contact with model fractal aggregates. Our simulations reveal that phase separation initially accelerates around the fractal due to the driving force of wetting, leading to the formation of the target composition patterns about the fractals, as previously observed for circular particles. After the formation of a wetting layer on the fractal, however, we observe a dramatic slowing-down in the kinetics of phase separation, and the characteristic domain size eventually "pins" to a finite value or approaches an asymptotic scaling regime as an ordinary phase if the phase separation loses memory of the aggregates when the scale of phase separation becomes much larger than the aggregate. Furthermore, we perform simulations to examine the effects of compositional interference between fractals with a view to elucidating interesting novel morphological features in the phase-separating mixture. Our findings should be helpful in understanding the qualitative aspects of the phase separation processes in mixtures containing particle aggregates relevant for coating, catalyst, adhesive, and electronic applications as well as in diverse biological contexts, where phase separation occurs in the presence of irregular heterogeneities. [ABSTRACT FROM AUTHOR]

We present the phase separation dynamics of a binary (AB), simple fluid (SF), and amphiphilic polymer (AP) mixture using dissipative particle dynamics simulation at d = 3. We study the effect of different AP topologies, including block copolymers, ring block copolymers (RCP), and miktoarm star polymers, on the evolution morphologies, dynamic scaling functions, and length scale of the AB mixture. Our results demonstrate that the presence of APs leads to significantly different evolution morphologies in SF. However, the deviation from dynamical scaling is prominent, mainly for RCP. Typically, the characteristic length scale for SF follows the power law R(t) ∼ tϕ, where ϕ is the growth exponent. In the presence of high AP, we observe diffusive growth (ϕ → 1/3) at early times, followed by saturation in length scale (ϕ → 0) at late times. The extent of saturation varies with constraints imposed on the APs, such as topology, composition ratio, chain length, and stiffness. At lower composition ratios, the system exhibits inertial hydrodynamic growth (ϕ → 2/3) at asymptotic times without clearly exhibiting the viscous hydrodynamic regime (ϕ → 1) at earlier times in our simulations. Our results firmly establish the existence of hydrodynamic growth regimes in low surfactant-influenced phase separation kinetics of binary fluids and settle the related ambiguity in d = 3 systems. [ABSTRACT FROM AUTHOR]

Temperature gradients induce mass separation in mixtures in a process called thermal diffusion and are quantified by the Soret coefficient ST. Thermal diffusion in fluid mixtures has been interpreted recently in terms of the so-called (pseudo-)isotopic Soret effect but only considering the mass and moment of inertia differences of the molecules. We demonstrate that the first moment of the molecular mass distribution, the mass dipole, contributes significantly to the isotopic Soret effect. To probe this physical effect, we investigate fluid mixtures consisting of rigid linear molecules that differ only by the first moment of their mass distributions. We demonstrate that such mixtures have non-zero Soret coefficients in contrast with ST = 0 predicted by current formulations. For the isotopic mixtures investigated in this work, the dependence of ST on the mass dipole arises mainly through the thermal diffusion coefficient DT. In turn, DT is correlated with the dependence of the molecular librational modes on the mass dipole. We examine the interplay of the mass dipole and the moment of inertia in defining the isotopic Soret effect and propose empirical equations that include the mass dipole contribution. [ABSTRACT FROM AUTHOR]

The Robeson bound is a theoretical limit that applies to kinetics-driven membrane separations of gas mixtures. However, this bound does not apply to sorption-driven membrane processes such as CO2/N2 separation, which lacks a theoretical explanation. As a result, we are uncertain about the factors that control the limiting behavior of sorption-driven separations. To address this issue, we employed a simple lattice model and dynamic mean field theory to examine the transport properties of disordered model structures, isolating sorption effects from purely kinetic effects. Our findings indicate that transport effects play a crucial role in sorption-driven processes, and perm-selectivity is consistently lower than sorption selectivity, which is an unattainable limit. We used basic geometric fragments of the structure to explain how transport effects emerge and manifest themselves in sorption-driven processes. [ABSTRACT FROM AUTHOR]

In gas transport systems of the nanoscale, fluid–surface interactions become the main forces governing the evolution of the flow state. In ideal nanoscale systems, such as atomically smooth carbon nanotubes, the characteristic lengths reduce to such an extent that the non-equilibrium entrance region comprises a large proportion of the domain. In this regime, the added effective resistance induced by the non-equilibrium entrance region becomes large enough that classical effusion models break down. The mechanisms behind the resistance in this regime are still poorly understood. A stochastic model of interfacial resistance is developed here, which allows for the determination of the effective diffusion coefficient via a novel finite-difference solution. We use this method to model free-molecular gas flow through long nanotubes, showing that such non-equilibrium effects may be present in systems of length scales currently within manufacturing capabilities. Finally, this model is used to discuss gas separation through aligned carbon nanotube arrays, with a focus on the effect of membrane length on the separation of a H2–CH4 mixture. [ABSTRACT FROM AUTHOR]

Separation of the mixture of ethylene (C2H4) and ethane (C2H6) to produce polymer-grade C2H4 is of prime importance in the petrochemical industry. In this context, metal–organic frameworks (MOFs) featuring tunable pore metrics and surface chemistry, especially those with inverse C2H6/C2H4 adsorption selectivity, hold great promise in energy-effective purification of C2H4 by adsorptive separation, but often encounter the well-known trade-off between adsorption selectivity and capacity. In this work, we report two new MOFs by deploying the pore-space-partition (PSP) strategy for the purpose of reducing the pore aperture size while retaining the gas-accessible pore volume. As a result, Ni-bodc-tpt (bodc = bicyclo[2.2.2]octane-1,4-dicarboxylic acid, tpt = 2,4,6-tri(4-pyridyl)-1,3,5-triazine) by combining optimal pore size, large cage pore volume, and rich C–H binding sites exhibits concurrently high C2H6 adsorption capacity (131.65 cm3 g−1) and C2H6/C2H4 selectivity (1.8) at 298 K and 1 bar, which is superior or comparable to many benchmark C2H6-selective MOFs. A dynamic breakthrough experiment demonstrates that high-purity C2H4 (>99.9%) can be harvested in one step from a binary mixture of C2H6/C2H4 (50/50, v/v), attesting to the feasibility of this new MOF as a prospective C2H4 purification agent. [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]

Large amount of energy is being contemporarily expended in carrying out separation and purification operations via thermodynamically inefficient conventional processes. Membrane-based separation technology has recently gained much attractiveness owing to its energy efficient process, reliable operation, low maintenance requirements, economical effectiveness, molecularly selective separation, and compact designing. Highly permeable and selective polymer-based flat-sheet polyether sulfone-based membranes were prepared followed by their insertion into compact spiral-wound modules for efficient carbon capture in this work. Carbon capture efficiency of prepared membranes and corresponding modules was evaluated by trialing them under various operating conditions on a custom-built laboratory-scale rig. Impact of precipitation technique and temperature on carbon capture capacity of resulting membranes and modules can be comprehended by precipitating cast films either through solvent evaporation or water submersion at two distinct temperatures of 5 and 20 °C. CO2 permeability of water-immersed membrane having 57 Barrer was uplifted to 61 Barrer for solvent-evaporated membrane. CO2/N2 selectivity of water-precipitated membrane was improved from 6 to 11 by precipitating at 5 °C instead of 20 °C. Flexible and frail properties of water-precipitated amorphous membranes can be turned into robust and relatively rigid semi-crystalline films owing to solvent evaporation. [ABSTRACT FROM AUTHOR]

To improve the accuracy of data processing and interpretation, effective suppression of the regional background field and extraction of the local anomaly field for further analyses represent urgent issues that need to be solved in the wide-field electromagnetic methods. The present study proposes an anomaly separation technique based on the residual method to develop the basic idea of regional field separation in gravity and magnetic exploration. The proposed technique can effectively suppress the regional background field and highlight local anomalies, such as faults and thin layers in inversion imaging, overcoming the shortcomings of traditional interpretation methods. Based on the interpolation-cutting method, a dynamically improved interpolation-cutting operator is proposed to obtain the regional background field by separating it from the local anomaly field. Furthermore, one- and two-dimensional complex geoelectric models are designed to perform calculations, inverse imaging, and anomaly separation. It has been demonstrated that the local anomaly information extracted by the anomaly separation technology describes accurate strata, structures, and faults, obviously superior to the traditional processing results. The proposed method is used to separate the anomalies from the wide-field electromagnetic inversion imaging in the Changning area of the southern Sichuan Province. The local information of the structures, thin layers, and faults obtained by the anomaly separation results is highly consistent with the seismic profile, indicating that the proposed anomaly separation technology is effective and reliable. Further, the proposed technology can effectively improve the inversion imaging accuracy and the interpretation reliability of traditional wide-field electromagnetic methods; thus, it has important application value. [ABSTRACT FROM AUTHOR]

Succinic acid (SA) is one of the top platform chemicals with huge applications in diverse sectors. The presence of two carboxylic acid groups on the terminal carbon atoms makes SA a highly functional molecule that can be derivatized into a wide range of products. The biological route for SA production is a cleaner, greener, and promising technological option with huge potential to sequester the potent greenhouse gas, carbon dioxide. The recycling of renewable carbon of biomass (an indirect form of CO2), along with fixing CO2 in the form of SA, offers a carbon-negative SA manufacturing route to reduce atmospheric CO2 load. These attractive attributes compel a paradigm shift from fossil-based to microbial SA manufacturing, as evidenced by several commercial-scale bio-SA production in the last decade. The current review article scrutinizes the existing knowledge and covers SA production by the most efficient SA producers, including several bacteria and yeast strains. The review starts with the biochemistry of the major pathways accumulating SA as an end product. It discusses the SA production from a variety of pure and crude renewable sources by native as well as engineered strains with details of pathway/metabolic, evolutionary, and process engineering approaches for enhancing TYP (titer, yield, and productivity) metrics. The review is then extended to recent progress on separation technologies to recover SA from fermentation broth. Thereafter, SA derivatization opportunities via chemo-catalysis are discussed for various high-value products, which are only a few steps away. The last two sections are devoted to the current scenario of industrial production of bio-SA and associated challenges, along with the author's perspective. [ABSTRACT FROM AUTHOR]

Dissolved gases in the aquatic environment are critical to understanding the population of aquatic organisms and the ocean. Currently, laser absorption techniques based on membrane separation technology have made great strides in dissolved gas detection. However, the prolonged water–gas separation time of permeable membranes remains a key obstacle to the efficiency of dissolved gas analysis. To mitigate these limitations, we demonstrated direct measurement of dissolved gas using the evanescent-wave absorption spectroscopy of a tapered silica micro-fiber. It enhanced the analysis efficiency of dissolved gases without water–gas separation or sample preparation. The feasibility of this sensor for direct measurement of dissolved gases was verified by taking the detection of dissolved ammonia as an example. With a sensing length of 5 mm and a consumption of ~50 µL, this sensor achieves a system response time of ~11 min and a minimum detection limit (MDL) of 0.015%. Possible strategies are discussed for further performance improvement in in-situ applications requiring fast and highly sensitive dissolved gas sensing. [ABSTRACT FROM AUTHOR]

Crystalline porous materials (CPMs), including covalent organic frameworks (COFs) and metal–organic frameworks (MOFs), are promising materials for advanced separation technologies. However, the challenge of transforming nanoscale CPMs into large‐area functional membranes hinders their application in the membrane separation process. Herein, a self‐standing pure COF (TpPa‐1) nanofiber membrane with high crystallinity, good flexibility, excellent mechanical properties, and scalability is prepared using an electrospinning process and polymer sacrificial template strategy. Subsequently, the COF nanofiber membrane is innovatively used to replace traditional inorganic discs, metal meshes, and polymer membranes as porous supports, and the COF–MOF composite CPM membrane is prepared through the tailorable and confined growth of zeolite imidazolium salt frame‐8 (ZIF‐8) on the surface of the COF membrane and in the gaps of the COF nanofibers. The COF–MOF composite membrane exhibits excellent permeability and significantly enhances separation selectivity for organic dyes. Moreover, MOF and COF form an interpenetrating network structure, and their similar chemical properties improve the interfacial stability between the two phases, giving the COF–MOF composite membrane good long‐term separation performance. This is the first self‐standing composite CPM membrane with excellent molecular sieving performance, which provides new insights into the design of high‐performance and robust composite membranes. [ABSTRACT FROM AUTHOR]

Pervaporation is considered the most promising technology for dehydration of bioalcohols, attracting increasing attention as a renewable energy source. In this regard, the development of stable and effective membranes is required. In this study, highly efficient membranes for the enhanced pervaporation dehydration of ethanol were developed by modification of sodium alginate (SA) with a polyethylenimine (PEI) forming polyelectrolyte complex (PEC) and graphene oxide (GO). The effect of modifications with GO or/and PEI on the structure, physicochemical, and transport characteristics of dense membranes was studied. The formation of a PEC by ionic cross-linking and its interaction with GO led to changes in membrane structure, confirmed by spectroscopic and microscopic methods. The physicochemical properties of membranes were investigated by a thermogravimetric analysis, a differential scanning calorimetry, and measurements of contact angles. The theoretical consideration using computational methods showed favorable hydrogen bonding interactions between GO, PEI, and water, which caused improved membrane performance. To increase permeability, supported membranes without treatment and cross-linked were developed by the deposition of a thin dense layer from the optimal PEC/GO (2.5%) composite onto a developed porous substrate from polyacrylonitrile. The cross-linked supported membrane demonstrated more than two times increased permeation flux, higher selectivity (above 99.7 wt.% water in the permeate) and stability for separating diluted mixtures compared to the dense pristine SA membrane. [ABSTRACT FROM AUTHOR]

The article reviews the most common analytical methods for calculating the parameters of minimum reflux condition during fractionation of multicomponent mixtures, taking account of the specified separation products quality requirements. A calculation procedure that makes it possible to simplify determination of minimum reflux or vapor ratios as well as of distillate or residue compositions under minimum reflux condition compared to the known methods is proposed and described. [ABSTRACT FROM AUTHOR]

As a common chlorinated nicotinic pesticide with high insecticidal activity, acetamiprid has been widely used for pest control. However, the irrational use of acetamiprid will pollute the environment and thus affect human health. Therefore, it is crucial to develop a simple, highly sensitive, and rapid method for acetamiprid residue detection. In this study, the capture probe (Fe3O4@Pt-Aptamer) was connected with the signal probe (Au@DTNB@Ag CS-cDNA) to form an assembly with multiple SERS-enhanced effects. Combined with magnetic separation technology, a SERS sensor with high sensitivity and stability was constructed to detect acetamiprid residue. Based on the optimal conditions, the SERS intensity measured at 1333 cm−1 is in relation to the concentration of acetamiprid in the range 2.25 × 10−9–2.25 × 10−5 M, and the calculated limit of detection (LOD) was 2.87 × 10−10 M. There was no cross-reactivity with thiacloprid, clothianidin, nitenpyram, imidacloprid, and chlorpyrifos, indicating that this method has good sensitivity and specificity. Finally, the method was applied to the detection of acetamiprid in cucumber samples, and the average recoveries were 94.19–103.58%, with RSD < 2.32%. The sensor can be used to analyse real samples with fast detection speed, high sensitivity, and high selectivity. [ABSTRACT FROM AUTHOR]

Magnetic separation technology is a physical separation method that uses the differences in magnetism between matter to separate them from each other by different motion behaviors in a non-uniform magnetic field. It is highly efficient, green, and environmentally friendly, with little change in the physical and chemical properties of raw materials. Magnetic separation technology is commonly used in the field of mineral processing engineering for magnetite, hematite, titanite, and other magnetic ferrous metal oxide minerals. This paper summarizes the application of magnetic separation technology for resource utilization and environmental treatment in different fields, such as non-metal decomposition, valuable metal recovery, use of magnetic carrier chemical separation, biomedical targeted magnetic separation, and use of magnetic species separation in water and wastewater treatment. We seek to review the application and potential of magnetic separation technology in various fields, emphasize their key role, and explore possible directions for their future development. [ABSTRACT FROM AUTHOR]

The separation of acetylene from carbon dioxide is challenging due to their almost identical molecular sizes and volatilities. Metal–organic frameworks (MOFs) in general are strong candidates for the separation of gas mixtures owing to the presence of functional pore surfaces that can selectively capture specific target molecules. Herein, we report a stable and easily synthesized bismuth-based MOF, Bi–BTC, which can achieve the separation of acetylene and carbon dioxide. We performed a detailed analysis of the sorption properties of the Bi–MOF. Bi–BTC shows good adsorption capacities for C2H2 with a capacity of 53.8 cm3 g−1 at 298 K and 1.0 bar, and C2H2/CO2 selectivity of 5.14/7.69 at 298 K and 1.0/0.1 bar. IAST selectivity calculations indicate that Bi–BTC possesses good separation capacity, and dynamic breakthrough experiments were performed to prove the separation of C2H2 and CO2. Bi–MOFs as a group of relatively less studied types of MOFs have interesting adsorption characteristics, and this study on Bi-based MOF will enrich three-dimensional Bi–MOF adsorbents for gas adsorption and separation applications. [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]

Tuning of vacancies in photocatalytic materials has emerged as a versatile strategy to enhance visible light absorption and photocatalytic activity. In this study, surface oxygen vacancies (defects) were incorporated on antimony tungstate to boost its photocatalytic activity, which was examined by studying the degradation of model pollutants under visible light irradiation. Specifically, a two-to-three-fold increase in photocatalytic activity was observed for oxygen vacancy-rich antimony tungstate in comparison to its pristine counterpart. This improvement in the photocatalytic performance can be attributed to the presence of oxygen vacancies in the material, which leads to an enhanced absorption of light, decrease in the recombination of charge carriers, and increase in the number of active sites. In addition, owing to the nature of the surface charge present, the photocatalysts were found to be selective for the degradation of cationic pollutants in comparison to anionic and neutral pollutants, and can thus be used for the separation of a mixture of pollutants. Furthermore, scavenger studies illustrate that holes play a major role in the photocatalytic degradation of pollutants. Moreover, the excellent photostability of oxygen vacancy-rich antimony tungstate over three consecutive cycles demonstrates its potential as a good photocatalyst for the degradation of pollutants. Overall, this study demonstrates that the engineering of surface vacancies on perovskite oxide materials can render them as efficient single component photocatalysts for environmental remediation applications. [ABSTRACT FROM AUTHOR]

There is a growing interest in the advancement of microscale electrokinetic (EK) systems for biomedical and clinical applications, as these systems offer attractive characteristics such as portability, robustness, low sample requirements and short response time. The present work is focused on manipulating the characteristics of the insulating post arrangement in insulator-based EK (iEK) systems for separating a binary mixture of spherical microparticles with same diameter (5.1 μm), same shape, made from the same substrate material and only differing in their zeta potential by ∼14 mV. This study presents a combination of mathematical modeling and experimental separations performed by applying a low-frequency alternating current (AC) voltage in iEK systems with 12 distinct post arrangements. These iEK devices were used to systematically study the effect of three spatial characteristics of the insulating post array on particle separations: the horizontal separation and the vertical separation between posts, and introducing an offset to the posts arrangement. Through normalization of the spatial separation between the insulating posts with respect to particle diameter, guidelines to improve separation resolution for different particle mixtures possessing similar characteristics were successfully identified. The results indicated that by carefully designing the spatial arrangement of the post array, separation resolution values in the range of 1.4–2.8 can be obtained, illustrating the importance and effect of the arrangement of insulating posts on improving particle separations. This study demonstrates that iEK devices, with effectively designed spatial arrangement of the insulating post arrays, have the capabilities to perform discriminatory separations of microparticles of similar characteristics. [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]

Polytetrafluoroethylene (PTFE) capillary membranes, known for the great chemical resistance and thermal stability, are commonly used in membrane separation technologies. However, the strong hydrophobic property of PTFE limits its application in water filtration. This study introduces a method whereby acrylamide (AM), N, N-methylene bisacrylamide (MBA), and vinyltriethoxysilane (VTES) undergo free radical copolymerization, followed by the hydrolysis-condensation of silane bonds, resulting in the formation of hydrophilic three-dimensional networks physically intertwined with the PTFE capillary membranes. The modified PTFE capillary membranes prepared through this method exhibit excellent hydrophilic properties, whose water contact angles are decreased by 24.3–61.2%, and increasing pure water flux from 0 to 1732.7–2666.0 L/m2·h. The enhancement in hydrophilicity of the modified PTFE capillary membranes is attributed to the introduction of hydrophilic groups such as amide bonds and siloxane bonds, along with an increase in surface roughness. Moreover, the modified PTFE capillary membranes exhibit chemical resistance, maintaining the hydrophilicity even after immersion in strong acidic (3 wt% HCl), alkaline (3 wt% NaOH), and oxidative (3 wt% NaClO) solutions for 2 weeks. In conclusion, this promising method yields modified PTFE capillary membranes with great hydrophilicity and chemical resistance, presenting substantial potential for applications in the field of water filtration. [ABSTRACT FROM AUTHOR]

Hydrofluorocarbons (HFCs) have important applications in different industries; however, they are environmentally unfriendly due to their high global warming potential (GWP). Hence, reclamation of used hydrofluorocarbons via energy-efficient adsorption-based separation will greatly contribute to reducing their impact on the environment. In particular, the separation of azeotropic refrigerants remains challenging, such as typical mixtures of CH2F2 (HFC-23) and CHF3 (HFC-32), due to a lack of adsorptive mechanisms. Metal–organic frameworks (MOFs) can provide a promising solution for the separation of CHF3–CH2F2 mixtures. In this study, the adsorption mechanism of CHF3–CH2F2 mixtures in TIFSIX-2-Cu-i was revealed at the microscopic level by combining static pure-component adsorption experiments, molecular simulations, and density-functional theory (DFT) calculations. The adsorption separation selectivity of CH2F2/CHF3 in TIFSIX-2-Cu-i is 3.17 at 3 bar under 308 K. The existence of similar TiF62− binding sites for CH2F2 or CHF3 was revealed in TIFSIX-2-Cu-i. Interactions between the fluorine atom of the framework and the hydrogen atom of the guest molecule were found to be responsible for determining the high adsorption separation selectivity of CH2F2/CHF3. This exploration is important for the design of highly selective adsorbents for the separation of azeotropic refrigerants. [ABSTRACT FROM AUTHOR]

The advent of two-dimensional nanomaterials, a revolutionary class of materials, is marked by their atomic-scale thickness, superior aspect ratios, robust mechanical attributes, and exceptional chemical stability. These materials, producible on a large scale, are emerging as the forefront candidates in the domain of membrane-based gas separation. The concept of defect engineering in 2D nanomaterials has introduced a novel approach in their application for membrane separation, offering an effective technique to augment the performance of these membranes. Nonetheless, the development of customized microstructures in gas separation membranes via defect engineering remains nascent. Hence, this review is designed to serve as a comprehensive guide for the application of defect engineering in 2D nanomaterial-based membranes. It delves into the most recent developments in this field, encompassing the synthesis methodologies of defective 2D nanomaterials and the mechanisms underlying gas transport. Special emphasis is placed on the utilization of defect-engineered 2D nanomaterial-based membranes in gas capture applications. Furthermore, the paper encapsulates the burgeoning challenges and prospective advancements in this area. In essence, defect engineering emerges as a promising avenue for enhancing the efficacy of 2D nanomaterial-based membranes in gas separation, offering significant potential for advancements in membrane-based gas separation technologies. [ABSTRACT FROM AUTHOR]

Nanofiltration is an energy efficient separation technology with yet not fully explored potential for in situ product recovery from fermentation solutions. In this work, a commercially available cellulose acetate nanofiltration membrane was investigated to separate different carboxylic acids from glucose in an aqueous solution. The membrane showed a high stability and good separation performance at low pH. Dead‐end and cross‐flow experiments revealed the transferability to real fermentation mixtures and demonstrate the possibility of coupling fermentation with in situ product separation. [ABSTRACT FROM AUTHOR]

Hydrocyclones are widely used in the separation of two-phase immiscible mixtures. In various application scenarios, three-phase hydrocyclones (3PH) are often urgently needed. In this work, the typical 3PHs are classified into six categories according to their structural characteristics. A comprehensive analysis of their structural feature, design points and processing difficulties are carried out to provide guidance for the design of 3PH structure. On this basis, the technical and economic analyses are conducted based on operating parameters, separation performance and pressure loss. Furthermore, the current problems and future development directions of the 3PH separation technology are summarized. Hydrocyclones mounted in series are suitable for application scenarios with low requirements for floor space and energy consumption. The 3PH of constructing axially adjacent two-stage cyclone chambers is applicable for long and narrow spaces such as downhole separation. The 3PHs with two radially nested cyclone chambers or one independent cyclone chamber are applicable to limited spaces such as offshore platforms. Considering the comprehensive performance of different 3PHs, the 3PH with a single three-phase cyclone chamber is more recommended in practical applications. The analysis results can provide theoretical and technical support for the design, optimization and technical promotion of high-efficiency 3PH separation technology. [ABSTRACT FROM AUTHOR]

Diffraction separation is crucial for high-resolution imaging of small-scale and discontinuous geological bodies, which are associated with oil and gas migration paths, reservoir spaces, or geological hazards in engineering. Diffraction and reflection show different geometric forms in the seismic common-offset domain, where reflection shapes are linear and diffractions are in the form of hyperbolic curves. One main challenge in diffraction separation technology lies in effectively suppressing reflected energy while preserving the diffraction energy. Curvelet is a sparse transformation with angle classification. After applying the curvelet transformation, reflections tend to be concentrated in a few coefficient matrices, while diffractions exhibit the opposite behavior. Based on the significant difference between reflections and diffractions in the curvelet domain, a diffraction separation and imaging method using cascaded filters in the curvelet domain is proposed that includes adaptive high-pass and median filters. Previous methods have encountered challenges in effectively separating reflected waves from diffracted waves, often struggling to simultaneously suppress reflected energy and preserve diffraction energy. These limitations can lead to difficulties in accurately identifying small-scale geological features and discontinuities. In contrast, the proposed method overcomes these limitations by leveraging the advantages of the curvelet transform and the cascaded filtering approach in the curvelet domain. The curvelet transform's sparse representation and angle classification properties enable effective concentration of reflections and diffractions in separate coefficient matrices. By employing adaptive high-pass and median filters, we achieve enhanced suppression of reflected energy and preservation of diffraction energy. Numerical experiments demonstrate that the proposed method not only eliminated high-slope and horizontal reflections but also preserved the energy-level and polarity-reversal of diffractions. Field application further confirms its potential value in accurately identifying complex stratigraphic structures and small-scale discontinuities. [ABSTRACT FROM AUTHOR]

The frequent occurrence of oil spills and the massive discharge of oily wastewater pose a significant threat to sustainable and healthy human development. Therefore, it is of importance to effectively separate oil–water mixtures. Inspired by nature, many superwetting surfaces/materials for oil–water separation have been developed in recent years. However, these surfaces/materials are subject to certain limitations and are unable to fully meet practical needs. With the advancement of laser technology, a novel solution has been provided for fabricating superwetting oil–water separation materials. Based on the design theory and separation mechanism, this paper summarizes the research progress of the laser-fabricated superwetting surfaces/materials for oil–water separation in recent years. First, the basic wetting theory, design strategy, and oil–water separation mechanism of the laser-fabricated materials are introduced in detail. Subsequently, the laser-fabricated oil–water separation materials, including superoleophilic/superhydrophobic materials, superhydrophilic/superoleophobic materials, and materials with reversible or superamphiphilic wettability, are systematically summarized and analyzed. Finally, the challenges and future research directions of laser-fabricated superwetting oil–water separation materials are discussed. [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]

Structural correlations between colloids in a binary mixture of charged and neutral spheres are calculated using computer simulations of the primitive model with explicit microions. For aqueous suspensions in a solvent of large dielectric constant, the traditional Derjaguin–Landau–Vervey–Overbeek (DLVO) theory of linear screening, supplemented with hard core interactions, reproduces the structural correlations obtained in the full primitive model quantitatively. However, for lower dielectric contrast, the increasing Coulomb coupling between the counterions and charged colloids results in strong deviations. We find a fluid–fluid phase separation into two regions either rich in charged or rich in neutral colloids, which is not reproduced by DLVO theory. Our results are verifiable in scattering or real-space experiments on charged-neutral mixtures of colloids or nanoparticles. [ABSTRACT FROM AUTHOR]

Spin separation technology is a key technology for realizing the detection function at the end of the rotational trajectory. It is also a necessary condition for the fuse control system to adjust its control strategy according to actual combat needs. To explore a new type of proximity fuse detection method, this article first designs a detection separation mechanism for the end of the trajectory. An interior ballistic model of the separation mechanism was then established through closed bomb tests and equivalent interior ballistic equations, and the aerodynamic parameters of the front-stage separation body at the moment of separation were obtained based on computational fluid dynamics numerical simulation. Finally, a separation dynamics model of the separation mechanism was established to analyze the motion state after the separation action of the front-stage separation body. The results demonstrate the feasibility of the proposed separation mechanism. The discrepancy between the simulation and experiment of the velocity increment for the front-stage separation body is about 1.07%. The attack angle for the front-stage separation body is below 2°, and the period with a displacement between two stage bodies greater than 3 m is around 0.365 s. This research can provide new ideas and theoretical references for the design of a similar fuse detection separation mechanism. [ABSTRACT FROM AUTHOR]

The metal–organic framework has great research value and application in oil–water separation, owing to its highly adjustable pore structure resulting from the combination of metal ions and organic ligands. In this work, the HKUST-1 membrane was prepared by an in situ growth method with purple copper mesh as the substrate, which showed superhydrophobic characteristics after stearic acid treatment. The surface morphology, chemical structure, and wetting behavior of SA-HKUST-1-CM were characterized by SEM, EDS, XRD, FTIR, XPS and contact angle tests. The results showed that the SA-HKUST-1-CM with rough micro–nano structures and low surface energy chemicals possessed superoleophilicity and superhydrophobicity (OCA = 0° and WCA = 154.6°). The membrane exhibited high separation efficiency (99%) and separation flux (2.36–6.85 × 104 L m−2 h−1) for the five tested oils under gravity drive. It had outstanding chemical and mechanical stability under harsh environmental conditions. In addition, due to its excellent reusability, the separation efficiency remained over 97.5% after 20 repetitions of the separation experiment. The wettability mechanism of the SA-HKUST-1-CM was explained via the chemical bonding theory and capillary force-based separation model. The mechanism of oil–water separation was additionally clarified in relation to the liquid bridge system. This super wetting MOF membrane with a simple preparation method, low cost and excellent performance has great application value and potential for oil–water separation. [ABSTRACT FROM AUTHOR]

Zeta potential is an important colloid parameter that dictates many intriguing phenomena such as colloid stability/aggregation, electrophoretic deposition and particle separation technology. Zeta potential is commonly used to characterise colloid particles' electrostatic interactions coupled with other forces such as van der Waals attraction, hydration and steric forces. However, the measurement of zeta potential involves complicated sample preparation and instrument/theory selection, often resulting in inaccurate measurement. Here, we developed a simple method that combines Stern–Grahame and Gouy–Chapman theories, for estimating zeta potential using parameters such as acid site pKa, acid site density and particle size. The method is applied to a wide range of carboxylic acids' functionalised colloid particles with various pKa. Results show that the new method is capable of capturing zeta potential dependence on pKa and pH. The new method can be applied to particles with complicated or multiple acid/base sites. Without the need for sample preparation/instrument, this new method is believed to save efforts for estimating zeta potential with good accuracy. [ABSTRACT FROM AUTHOR]

Membrane technology is considered to be an effective method for the treatment of oily wastewater. However, membrane fouling caused by oil adsorption seriously hinders its practical application in oil–water separation. In this study, membrane separation technology was combined with surface modification technology. A commercial hydrophobic polyvinylidene fluoride (PVDF) membrane was used as the base membrane material. Polydopamine (PDA) with adhesion was introduced into the PVDF membrane, and DETA was modified on the PVDF membrane by a Schiff base reaction between PDA and diethylenetriamine (DETA). On this basis, polyvinylpyrrolidone (PVP) with high hydrophilicity and halloysite nanotubes (HNTs) with a rough porous structure were introduced, and a PVDF–PDA–DETA@PVP@HNT membrane with superhydrophilicity–underwater superoleophobicity was successfully prepared. Then, the effects of different amounts of HNTs on the surface morphology and chemical composition of the films were studied by scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. When the addition amount of HNTs was 0.05 g, the membrane showed high separation efficiency (more than 99%) and separation flux (2268–2406 L m−2 h−1) for various oil-in-water emulsions. After 8 cycles, the emulsion separation efficiency was higher than 93%. After soaking in different pH solutions for 12 h, the water contact angle (WCA) was 0° and the underwater oil contact angle (UOCA) was greater than 150°, showing excellent chemical stability. This strategy has the advantages of convenient preparation, economy and high efficiency, and has broad application potential in industrial oily wastewater. [ABSTRACT FROM AUTHOR]

Extraction of native-like lignin from lignocellulose is crucial for maximizing the value of all three major components of biomass. In this study, molecular dynamics was employed to reveal the essence of lignin condensation during the pretreatment of biomass with a promising acidic hydrotropic solution (AHS) at the molecular level. Diols were discovered to effectively suppress the excessive acidity of p-toluenesulfonic acid (pTsOH) in AHS while maintaining its solubilizing effect below a minimal hydrotropic concentration (MHC). The experimental results confirmed that the combined use of 1,4-butanediol and pTsOH can extract native-like lignin under mild conditions. The retention of lignin's β-O-4 linkages can exceed 90%, and the lignin extraction rate was over 80%. The obtained lignin can enhance the efficacy of chemical sunscreens, doubling the sun protection factor (SPF). Simultaneously, the residual cellulose was readily hydrolyzed into glucose by cellulase. This strategy demonstrates excellent adaptability to various biomass sources, including herbaceous species, hardwoods, and highly recalcitrant softwoods. The work lays the theoretical foundation for the precise control of biomass component separation using AHS, contributing to the development of mild and efficient component separation technologies in the future. [ABSTRACT FROM AUTHOR]

A semi-packed gas chromatographic column has the advantages of high specific surface area and low column pressure. We report that the stagnation regions formed in the adjacent posts along the channel of the semi-packed columns can decrease the area and height of chromatographic peaks, which makes it difficult to detect low-concentration mixed gases. A semi-packed column with staggered elliptic cylindrical post arrays (SC-S) made using a micro-electro-mechanical system technique is presented, and the separation performance of SC-S is compared with that of a semi-packed column with aligned elliptic cylindrical post arrays (SC-A). The simulation results show that the width of stagnation regions in SC-S is 86.89% smaller than that in SC-A. The experimental results indicate that the area and height of chromatographic peaks increased as stagnation regions reduced. In the separation of the alkane mixture from C8 through C10 with 10 ppm concentration, the chromatographic peak of decane was hardly identified in SC-A while the chromatographic peak in SC-S was still clearly visible. The chromatographic peak heights of octane and nonane were increased by 65.06% and 130.00%, respectively, in SC-S. The peak areas of octane and nonane were increased by 120.45% and 168.18%, respectively. [ABSTRACT FROM AUTHOR]

Magnetic molecularly imprinted polymers (MMIPs) have fused molecular imprinting technology with magnetic separation technology, emerging as an innovative material capable of recognizing specific molecules and efficiently separating target substances. Their application to the extraction and purification of mycotoxins has great potential, due to the toxicity and economic impact of these contaminants. In this work, MMIP has been proposed as a sample treatment for the determination of main four aflatoxins (B1, B2, G1 and G2) in pig feed. The MMIP was formed through the integration of magnetic material (Fe3O4) with commercial molecularly imprinted polymers, avoiding the synthesis step and, therefore, simplifying the process. The analyses were carried out by high-performance liquid chromatography with fluorescence detection and the method was validated and limits of quantification (LOQs) between 0.09 and 0.47 ng/g were obtained, below the allowed or recommended levels by the European Union. Repeatability and intermediate precision showed relative standard deviations lower than 10% in all cases and trueness ranged from 92 to 111%. Finally, the proposed method was applied to 31 real pig feed samples, detecting aflatoxins with concentrations between 0.2 and 3.2 ng/g. [ABSTRACT FROM AUTHOR]

Understanding the evolution of water droplets moving in a highly viscous bulk flow (e.g., bitumen) has attracted increasing attention in the context of numerous separation technologies due to various issues relating to the environment (re-use of water) and engineering failures (corrosion of pipelines). With this in mind, the main objectives of this work are to explore the dynamics of water droplets with a diameter of seven micrometers, moving in highly viscous bitumen flowing through a smoothly converging and diverging 11-micron channel using three-dimensional (3D) and two-dimensional (2D) droplet-resolved simulations and to adjust an existing population balance model (PBM) to predict geometry-driven coalescence for different flow rates. The Eulerian–Eulerian (EE) method coupled with a new PBM is used to predict the behavior of water droplets with a diameter of 7 μm. Numerical simulations were carried out for various capillary numbers (0.1 < C a < 3) and compared with the volume of fluid method combined with the level-set function (CLSVOF). Adaptive mesh refinement (up to six levels) was used in 3D and 2D CLSVOF simulations, producing interface cells measuring up to 30 nm. Good agreement was observed between EE-PBM and CLSVOF models. For comparison, we show the results of 2D CLSVOF simulations. This new PBM model can be used to predict water–oil separation in new cascade-formed geometries to enhance the coalescence of water droplets in highly viscous bulk flows. [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]

Zeolites, a group of minerals with unique properties, have been known for more than 250 years. However, it was the development of methods for hydrothermal synthesis of zeolites and their large-scale industrial applications (oil processing, agriculture, production of detergents and building materials, water treatment processes, etc.) that made them one of the most important materials of the 20th century, with great practical and research significance. The orderly, homogeneous crystalline and porous structure of zeolites, their susceptibility to various modifications, and their useful physicochemical properties contribute to the continuous expansion of their practical applications in both large-volume processes (ion exchange, adsorption, separation of mixture components, catalysis) and specialized ones (sensors). The following review of the knowledge available in the literature on zeolites aims to present the most important information on the properties, synthesis methods, and selected applications of this group of aluminosilicates. Special attention is given to the use of zeolites in agriculture and environmental protection. [ABSTRACT FROM AUTHOR]

Proteins are the material basis of life and the primary carriers of life activities, containing various impurities that must be removed before use. To keep pace with the increasing complexity of protein samples, it is essential to constantly work on developing new purification technologies for downstream processes. While traditional downstream purification methods rely heavily on protein A affinity chromatography, there is still a lot of interest in finding safer and more cost-effective alternatives to protein A. Many non-affinity ligands and technologies have also been developed in biological purification recently. Here, the current status of biotechnology and the progress of protein separation technology from 2018 to 2023 are reviewed from the aspects of new preparation methods and new composite materials of commonly used separation media. The research status of new ligands with different mechanisms of action was reviewed, including the expanded application of affinity ligands, the development prospect of biotechnology such as polymer grafting, continuous column technology, and its new applications. [ABSTRACT FROM AUTHOR]

Aligned with the recent trend and imperative to reduce separation layer thickness in gas separation membranes to the nanometer scale in order to raise permeance to levels that can render them competitive with respect to other gas separation technologies, a novel approach and device for fabricating defect-free composite hollow fiber (HF) membranes by dip-coating is described. The presented method avoids the fundamental drawbacks of state-of-the-art techniques for applying a thin gas separation layer onto a porous HF substrate, providing a safe but, at the same time, easily up-scalable way of producing HF membranes at a relatively high production rate. As a basic concept, hanging HF substrates are coated by allowing the coating solution to flow and drip along their external surface. The adaptability of this method, stemming from the array of available coating solutions (a plethora of dispersed nanofillers) and the multitude of substrate options, holds great promise for the fabrication of highly selective and defect-free composite HF membranes. [ABSTRACT FROM AUTHOR]

The next generation of ultrahigh bypass ratio civil aero-engines promises notable engine cycle benefits. However, these benefits can be significantly eroded by a possible increase in nacelle weight and drag due to the typical larger fan diameters. More compact nacelles, with shorter intakes, may be required to enable a net reduction in aero-engine fuel burn. The aim of this paper is to assess the influence of the design style of short intakes on the unsteady interaction under crosswind conditions between fan and intake, with a focus on the separation onset and characteristics of the boundary layer within the intake. Three intake designs were assessed, and a hierarchical computational fluid dynamics (CFD) approach was used to determine and quantify primary aerodynamic interactions between the fan and the intake design. Similar to previous findings for a specific intake configuration, both intake flow unsteadiness and the unsteady upstream perturbations from the fan have a detrimental effect on the separation onset for the range of intake designs. The separation of the boundary layer within the intake was shock driven for the three different design styles. The simulations also quantified the unsteady intake flows with an emphasis on the spectral characteristics and engine-order signatures of the flow distortion. Overall, this work showed that is beneficial for the intake boundary layer to delay the diffusion closer to the fan and reduce the preshock Mach number to mitigate the adverse unsteady interaction between the fan and the shock. [ABSTRACT FROM AUTHOR]

The problem on the optimum organization of the rectification of a multicomponent mixture in a rectifying column was considered. It is shown that, in the case where heat is supplied to the boiler of the column and is removed from its dephlegmator, the boundary of the realizable-load range of the column represents a parabola convex upwards with two characteristic parameters. The interrelation between the indicated characteristic parameters and the kinetics of the heat- and mass-transfer processes in the column, the composition of the mixture separated in it, and the mixture separation boundary selected was determined. The consequences of the possibility of parametrization of the boundary of the realizable-load range of a rectifying column are discussed. A rule for the choice of the boundary of separating a multicomponent mixture has been formulated. [ABSTRACT FROM AUTHOR]

The challenges related to the sustainability and safety policies to use the technologies for separating industrial contaminants in the oil and gas industry necessitate an investigation based on these policies. The criteria are in four economic, technical, social, and environmental aspects (as sustainability principles), and three applicability, functionality, and integrity aspects (as safety principles). The research aims at extending a novel decision support system (DSS) by integrating MEREC (method based on the removal effects of criteria) and MABAC (multi-attributive border approximation area comparison) methods under the Pythagorean fuzzy set. Its notable advantages are that renders a stronger expression of uncertainty and the decision-making process is more closely managed. Also, it allows the decision-maker (DM) to evaluate in a wider area and avoid data and conflict among the decision-making team. The industrial separation technologies prioritization is implemented with the DSS. These technologies have been taken into account for contamination control in the sector of Iran's natural gas processing. The results of the prioritization are: High-efficiency liquid–gas coalescer technology, mesh pad technology, filter separator technology, cyclonic separator technology, vane pack technology, two-phase separator technology, and supersonic separator technology. The high-efficiency liquid–gas coalescer technology is selected as the preferable alternative. [ABSTRACT FROM AUTHOR]