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Separation processes

Separation processes

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Separation processes are techniques used in chemical engineering and industrial processes to separate components of a mixture based on differences in their physical or chemical properties. These processes are essential for purifying substances, recovering valuable materials, and facilitating various applications in industries such as pharmaceuticals, petrochemicals, and food processing.
lightbulbAbout this topic
Separation processes are techniques used in chemical engineering and industrial processes to separate components of a mixture based on differences in their physical or chemical properties. These processes are essential for purifying substances, recovering valuable materials, and facilitating various applications in industries such as pharmaceuticals, petrochemicals, and food processing.

Key research themes

1. How can gravity-driven separation techniques be optimized and diversified for mineral and particulate separation?

This theme focuses on classical gravity separation methods and their recent innovations, emphasizing the optimization of operational parameters and adaptation to finer particle recovery and hard rock mineral processing. This research area matters because gravity separation remains a cost-effective and environmentally friendly technique, yet faces challenges in fine particle separation and operational control, necessitating advances in equipment design and process understanding.

GRAVITY SEPARATION: OLD TECHNIQUE/NEW METHODS
by Shihab Uddin

2017

Key finding: This paper provides a detailed comparative review of main gravity separation devices, highlighting new equipment such as In Line Pressure jigs that operate under elevated pressure (~70 kPa) for compact operation and minimal... Read more
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Modeling of Aerodynamic Separation of Preliminarily Stratified Grain Mixture in Vertical Pneumatic Separation Duct
by Ernest Popardowski

2024, Applied Sciences

Key finding: The research models the effect of preliminary stratification of grain mixtures before entering vertical pneumatic separators to enhance separation of light impurities by creating layers enriched in these impurities. The study... Read more
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Analysis of Segregation Process Using the Broken Line Model. Theoretical Base
by Józef Suchy and 
1 more
Bohdan Mochnacki

2016

Key finding: By decoupling thermal gradients from convective velocity in a horizontal cavity filled with binary fluid, the study analytically and numerically determines optimal parameters (mass Péclet and Rayleigh numbers) for maximizing... Read more
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2. How can integration of reaction and separation processes in a single unit improve efficiency and control in chemical manufacturing?

This theme explores reactive separation processes combining chemical reactions and separation in unified equipment such as reactive distillation columns, focusing on control strategies to manage inherent nonlinearities and operational constraints. Approaches in process integration aim to reduce energy consumption, equipment footprint, and waste production while ensuring product quality. Understanding and implementing advanced control methods like Model Predictive Control (MPC) is critical to handle complex interactions, maintain stability, and optimize performance in these integrated systems.

Implementation of MPC Strategy in Reactive Separation Techniques and Its Benefits: A Demonstration with Natural Gas Sweetening Process
by Rames Panda

2024, Model Predictive Control - Theory and Applications [Working Title]

Key finding: This study demonstrates the application of advanced nonlinear Model Predictive Control (MPC) strategies to reactive separation processes, specifically natural gas sweetening, which intrinsically exhibit nonlinear dynamics due... Read more
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3. What are the advances in membrane-based and supported separation technologies for energy and environmental applications?

This area investigates novel membrane materials and supported systems that enable selective separation of gases (e.g., CO2 from flue gases, olefin/paraffin separations) or contaminants (e.g., antibiotics from wastewater). Enhanced materials such as mixed matrix membranes incorporating functional nanomaterials aim to overcome trade-offs between permeability and selectivity, while supported ionic liquid membranes offer high extraction efficiency with tunable selectivity. Molecular-level understanding of transport mechanisms guides material design. These efforts address energy efficiency, environmental sustainability, and industrial applicability of membrane-based separation.

Carbon Dioxide Separation Technologies: Applicable to Net Zero
by Gourav Rath

2023, Energies

Key finding: This comprehensive review delineates state-of-the-art CO2 separation technologies including adsorption, absorption, membrane-based and cryogenic distillation processes, contrasting their operational efficiencies, energy... Read more
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Fabrication and performance evaluation of mixed matrix membrane comprising Pebax and graphene hydroxyl in olefin/paraffin separation
by Polyolefins Journal

2025, Polyolefins Journal

Key finding: The study fabricates mixed matrix membranes (MMMs) incorporating hydroxyl-functionalized graphene nanosheets into a Pebax 1657 polymer matrix, achieving enhanced propylene permeability (~90 barrer) and selectivity (C3H6/C3H8... Read more
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Unlocking transport mechanism of sulfamethoxazole in supported ionic liquid membrane: Insights from experimental and molecular dynamics studies
by Mohd Hazarel Zairy Mohd Harun

2024

Key finding: This work optimizes supported ionic liquid membranes (SILMs) employing Aliquat 336 as carrier embedded in PVDF supports for selective extraction of sulfamethoxazole (SMX) antibiotic from aquaculture wastewater. The SILM... Read more
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4. How can the application of chemometrics improve data analysis and method optimization in separation science and related forensic/toxicological analyses?

With increasingly complex and rich datasets from multi-dimensional separation techniques (e.g., chromatography), chemometric approaches—multivariate analysis, experimental design, pattern recognition—enable extraction of meaningful information, enhanced method development, and better decision-making. This theme covers applications in analytical chemistry including volatile, soluble, and colloidal samples and extends to forensic and toxicological contexts where data robustness, automation, and reliable interpretation are critical for regulatory and legal purposes.

Extracting Information and Enhancing the Quality of Separation Data: A Review on Chemometrics-Assisted Analysis of Volatile, Soluble and Colloidal Samples
by Nicholas Kassouf

2024, Chemosensors

Key finding: This review synthesizes the role of chemometric techniques—such as PCA, cluster analysis, LDA, PLS, and experimental design—in improving data elaboration and method design in separation science. Applications across gas... Read more
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5. How can modeling and predictive analytics accelerate the selection of separation media and process parameters for biotherapeutics and metallurgical applications?

This theme focuses on developing predictive models and software tools using physicochemical property inputs to expedite and optimize separation media selection and process design, minimizing experimental resource usage. Examples include surface-property based prediction of monoclonal antibody behavior on hydrophobic interaction chromatography resins and web-based automated sizing tools for multiphase separators in oil and gas. These modeling approaches enhance efficiency, accuracy, and reliability in designing separation processes critical for pharmaceutical manufacturing and hydrocarbon processing.

Modeling the behavior of monoclonal antibodies on hydrophobic interaction chromatography resins
by Sheldon Oppenheim

2024, Bioresources and bioprocessing

Key finding: Using a dataset comprising seven mAbs across 13 HIC resins paired with measured physicochemical attributes (e.g., surface hydrophobicity, charge, thermal stability), this study develops QSAR-based predictive models with high... Read more
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Tech Article: «Separator Sizing Software Development Proposal»
by Mariam Kumarkhan

2024, Proposal for the Development of Tailored Software for Separator Sizing in Oil & Gas Applications

Key finding: This proposal outlines the development of 'Separator Pro', a web-based software integrating advanced engineering algorithms with user-friendly interfaces for automated selection and sizing of multiphase separators (horizontal... Read more
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6. What are the emerging materials and process developments for enhanced adsorption-based removal of organic and biological contaminants from wastewater?

This research theme explores the design and characterization of novel adsorbent materials modified with polymers or functional groups to improve adsorption capacity, selectivity, and regeneration for contaminants such as pesticides, antibiotics, and dyes in aqueous environments. The optimization of surface chemistry, porosity, and interaction mechanisms is critical for achieving efficient contaminant removal while ensuring reusability and operational feasibility. Understanding adsorption kinetics and isotherms under various conditions guides development of sustainable wastewater treatment technologies.

Removal of organic contamination from wastewater using granular activated carbon modified-Polyethylene glycol: Characterization, kinetics and isotherm study
by Hossein Mashhadimoslem

2024, plosone

Key finding: This study synthesizes granular activated carbon (GAC) modified with polyethylene glycol (PEG) and evaluates its performance for adsorption of Diazinon (DZ), Amoxicillin (AMX), and Crystal Violet (CV) from aqueous solutions.... Read more
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    • All papers in Separation processes

    Sorption of dyes from aqueous solutions onto fly ash
    by Pavel Janos

    2003, Water Research

    Brown coal fly ashes were tested as potentially low-cost sorbents for the removal of synthetic dyes from waters. It was shown that both basic (cationic) as well as acid (anionic) dyes can be sorbed onto the fly ash. The adsorption can be... more
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    Removal of metal ions from aqueous solutions by sorption onto untreated low-rank coal (oxihumolite
    by Pavel Janos

    2007, Separation and Purification Technology

    Naturally occurring kind of weathered and oxidized young brown coal called oxihumolite was used for an adsorptive removal of heavy metal cations (Cd 2+ , Cu 2+ , Co 2+ , Ni 2+ , Pb 2+ , Zn 2+ ) from waters. A working range for the... more
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    Kinetic, isotherm, and thermodynamic investigations of uranium(VI) adsorption on synthesized ion-exchange chelating resin and prediction with an artificial neural network
    by hamid heshmati
    In this study, an amidoximated chelating ion-exchange resin was prepared using polyacrylonitrile grafted potato starch. The resin characterizations such as specific surface area, pore volume, average pore radius, and Fourier transform... more
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    A packed bed membrane reactor for production of biodiesel using activated carbon supported catalyst
    by Abdul Aziz Abdul Raman

    2011

    In this study, a novel continuous reactor has been developed to produce high quality methyl esters (biodiesel) from palm oil. A microporous TiO2/Al2O3 membrane was packed with potassium hydroxide catalyst supported on palm shell activated... more
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    Ionic liquids in supported liquid membrane technology
    by Mohd Ali Hashim

    2011, Chemical Engineering Journal

    The selection of separation process of organic compounds is a critical issue in the chemical industry. Different conventional methods, such as coagulation, precipitation, ion exchange, electrodialysis, adsorption, ultrafiltration and... more
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    Liquid-liquid extraction-based process concepts for recovery of carboxylic acids from aqueous streams evaluated for dilute streams
    by Thomas Brouwer

    2018, Liquid-liquid extraction-based process concepts for recovery of carboxylic acids from aqueous streams evaluated for dilute streams

    Liquid-liquid extraction Conceptual process design Switchable solvents Solvent regeneration a b s t r a c t In this manuscript carboxylic acid extraction processes are reviewed and compared on energy efficiency, especially in situations... more
    Fig. 1 - Basic process scheme for LLX with recovery of high-boiling solvent by distillation. “Trace amount; can be isolated by further polishing stages. #Carboxylic acid.
    Fig. 2 —- Basic process scheme for LLX-based carboxylic acid recovery process utilizing low-boiling solvent to be regenerated by distillation. “Trace amount: can be isolated by further polishing stages. ?Carboxylic acid. demands (Jongmans et al., 2012; Yue et al., 2011). An important element in any extraction process is solvent loss into the raffi- nate phase, and to limit that, ILs can be designed to be highly hydrophobic and exhibit significant carboxylic acid extrac- tion capacities at the same time (e.g. phosphonium-based ILs) (Blahusiak and Schlosser, 2014; Martak and Schlosser, 2007, 2008). Washing the raffinate phase with a hydrophobic sub- stance (e.g. hexane) to recover any leaching IL may also be devised (Garcia-Chavez et al., 2013). ILs have also been used as diluents hosting organophosphorus compounds (Matsumoto et al., 2004), and even in aqueous two-phase systems (Pratiwi et al., 2015). ite solvent in systems including mineral impurity is that the composite solvent tends to interact with the mineral impurity resulting in undesired co-extraction thereof (Eyal and Canari, 1995; Reyhanitash et al., 2016). 2.1.2. Innovations in high-boiling solvents 2.1.2.1. Ionic liquids. Ionic liquids (ILs) have gained much interest in the recent literature on (carboxylic acid) extrac- tions, as they have been shown to possess certain character- istics that appear superior to those of conventional solvents (Blahusiak et al., 2013; Martak and Schlosser, 2007, 2008; Oliveira et al., 2012; Tonova et al., 2014). Most importantly, they exhibit higher carboxylic acid distribution coefficients at very low raffinate concentrations, ideal for dilute aque- ous streams and leading to lower solvent to feed ratios (S/Fs) (Bai et al., 2017; BlahuSiak et al., 2013; Martak and Schlosser, 2007; Reyhanitash et al., 2016). Furthermore, their higher boiling/decomposition temperature enables thermal solvent regeneration to be performed in a wider temperature range (Mai et al., 2014; Poole and Poole, 2010), and their design flexibility makes them capable of meeting various extraction
    Fig. 3 - Process scheme for LLX-based carboxylic acid recovery process utilizing low-boiling solvent to be regenerated by pack-extraction with water or non-volatile alkali solution. Trace amount; can be isolated by further polishing stages. #Carboxylic acid. ° Alkali solution of an alkaline or alkali eartt metal. “Alkaline salt of carboxylic acid.
    Fig. 4 - Simplified view of the process proposed by Urbas (1983).
    Fig. 5 - Heater duty of novel processes as a function of their initial carboxylic acid concentration. Carboxylic acid concentration in extract is calculated with a constant distribution factor, figure (A) acetic acid, (B) acrylic acid, (C) lactic acid
    Fig. 6 - Key energy demands of processes proposed by Seader et al. (2010), Merciér (1978), Schon (2010), De Haan et al. (2013, 2014) and Urbas (1983) with their own initial carboxylic acid concentrations as listed in Table 1 (top), and with their initial carboxylic acid concentrations set to 1.0 wt% (bottom). Heater and cooler duties are expressed as MJ/kg of carboxylic acid product, and electrical duty as kW/kg of carboxylic acid product.
    A summary of the key energy demands of the novel pro- cess when they operate at their own initial carboxylic acid
    Table A1 - Specifications given by Seader et al. (2010) and obtained with mass balance closure.
    Fig. A3 — Process for recovery of HLa from fermentation broth proposed by De Haan et al. (2 ‘Magnesium lactate. Lactic acid. ‘Trace amount. 2 a Estimated per kg of the carboxylic acid in the product stream. Simulated by assuming a full conversion of tributyl ammonium acetate to acetic acid which is consequently distilled. The heater duty is lowered by heat integration between the bottom product and the feed. A minimum temperature difference between th hot-outlet and cold-inlet of 10°C was held in the heat exchanger. These coolers lower the temperature of the distillate and bottom product to 25°C.
    Schon (2010) proposed a process using liquefied propylene and/or propane as the solvent to extract acrylic acid from aqueous solutions. This method replaces the distillation col- umn needed for solvent regeneration with a few flash drums operating at low temperatures. This enables the use of waste heat a major part of which is supplied to prevent the equip-
    Fig. A5 - Acetic acid extraction and solvent regeneration process proposed by Merciér (1978) “Trace amount. 3 Acetic acid. >Butanol. ‘Butyl acetate. 4Ammonium acetate.
    to reduce waste to preserve living quality on Earth, circular economy has become a popular topic of research (McDonough and Braungart, 2002). An extensive number of studies are in progress to discover or improve technologies by which chemicals can be produced from waste. In an attempt to reduce the carbon footprint, production of chemi- cals from renewable resources is studied extensively as well (Du et al., 2015; Garcia Alba et al., 2012; Kamm et al., 2008; Luque et al., 2014; Oudenhoven and Kersten, 2014; van Putten et al., 2013; Zakzeski et al., 2010). Fermentation enables production of chemicals from waste and renewable resources with a high efficiency, and potentially at a low cost. Since numerous types of microorganisms are available to be used for fermentation, a wide variety of chemicals can be produced by fermentation, ranging from commodity chemicals to pharmaceutical intermediates (Ajikumar et al., 2008, 2010; Straathof, 2014). A wide vari- ety of carbon sources for fermentation have also been reported, ranging from glucose to industrial wastewater such as chemical, food or paper industry wastewater (Angenent et al., 2004; Corma et al., 2007). Sugar- rich streams isolated from pyrolysis oil can also be fed to a fermenter (Li et al., 2016c). While product diversity and feedstock flexibility are among major benefits of fermentation, low product concentration is a major drawback which results in significant downstream costs (Kiss et al., 2016). Nomenclature
    Table 1 - Specification of novel processes; feed concentrations are taken from reference patents and product concentrations are obtained with simulations. According to the specifications stated in the corresponding patent. Using the patent specifications, a product concentration of 99.8 wt% could not be reached. An additional distillation column was simulated to reach a carboxylic acid concentration of 99.8 wt%. Using the patent specifications, a product concentration of 99.8 wt% could not be reached. An additional distillation column was simulated to reach a carboxylic acid concentration of 99.8 wt%. The target concentration of 99.8 wt% could not be reached using an evaporation column. Using the patent specifications, a product concentration of >99.9 wt% was reached. Trace amounts of other compounds in the product stream were in ppm scale.
    2 A reported Kp for lactic acid of 0.33 in a $ of 1 was correlated with a reported 3 of 1.33 to obtain an extracted wt% of 44 for lactic acid. > A reported Kp for lactic acid of 0.37 in a 3 of 1 was correlated with a reported 3 of 4.16 to obtain an extracted wt% of over 100, therefore complete extraction was assumed. © Methyl isobutyl ketone (MIBK) was chosen from the suggested selection as the solvent.
    4 Estimated per kg of the carboxylic acid in the product. Simulated by assuming a total conversion of MgCl, to MgO and volatile byproducts are evaporated in a flash vessel. The heater duty is lowered by heat integration between the top product and the feed. A minimum temperature difference between th« hot-outlet and cold-inlet of 10°C was held in the heat exchanger. Used to lower the distillate to 20°C. Estimated using extemal coolers to lower the stream to 20°C.
    @ Here the inlet and outlet pressures are given respectively. Table A7 - Specifications given by Schon (2010) and obtained with mass balance closure.
    Table A9 - Specifications given by Merciér (1978) and obtained with mass balance closure.
    Table A10 - Selected specifications and energy demands of process proposed by Merciér (1978). Simulation was performed with Aspen Plus and NRTL fluid package.
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    Perspective on Technical Lignin Fractionation
    by Art Ragauskas

    2020, ACS Sustainable Chemistry and Engineering

    Technical lignin extracted from pulping and biorefining processes provides a class of complex and polydisperse phenolic polymers. Preparation of lignin with lower structural complexity and polydispersity through lignin fractionation is... more
    Scheme 1. Three Phenyl Propane Precursor of Lignin and Its Chemical Model Structure’ Table 1. Abundance of Major Linkage in Softwood and Hardwood Lignin’
    Figure 1. Schematic illustration of the traditional pulping recovery process and “debottleneck” process for lignin recovery and separation
    Figure 2. Organosolv switchgrass and pine lignin fractionation using acetone—water mixture.* Fractionation of pine and switchgrass organosolv lignin using acetone—water mixture and properties of fractions were examined.** The pine and switchgrass raw material were first cooked in an aqueous ethanol solution (65:35, v/v) with sulfuric acid (0.9%, w/w) as the catalyst and the extracted lignin was precipitated and filtered by addition of water and dried at room temperature. Each lignin sample was dissolved in 60% acetone— water mixture (pretest indicated 100% solubility in 60% acetone and above). The concentration of acetone was reduced gradually, and the precipitated fraction was filtered (Figure 2). The solubility of switchgrass and pine organosolv lignin in pure acetone was 85% and 81%, respectively.
    Figure 3. Effect of acetone concentration on the molecular weight and PDI (A, B) and functional groups (C, D) of fractionated switchgrass and pine organosolv lignin.*°
    Scheme 2. Schematic Representation of a Multistage Membrane Fractionation System
    the lignin from kraft pulping is combusted in the chemical recovery process to recover pulping chemicals and energy mainly due, in part, to a lack of high-value applications for lignin in the marketplace. For commercial lignin applications, water- soluble lignosulfonates derived from the sulphite pulping process are the main product so far. minor part with the sulphite method. Regarding nonwood or annual plants, the soda process is a main manufacturing platform. The kraft pulping process uses NaOH/Na,S as pulping chemicals at an elevated temperature. This process is the dominate chemical pulping process and is the main potential lignin source to supply in the market. However, the main part of
    Table 2. Methods for Lignin Fractionation’’
    Table 4. Effect of Fractionation pH on the Molecular Weight, Charge, and Particle Size” Table 3. Effect of Fractionation pH on Their Properties”
    Table 5. Properties of Kraft Lignin Fractions Collected from the Soluble Part in Each pH*®
    maximum polydispersity. Antioxidant activity of all the fractions measured using ROO® scavenging as well (Table 5) indicated more or less the same results. Only the fraction collected at pH 1 indicated higher antioxidant activity. at a lower pH exhibited a higher content of acidic groups. As mentioned, lignin has a colloidal shape in solution with negative charges which repel one another to keep the solution stable. The charge on the lignin particles as determined by zeta potential and their size was reported in this work as a function of fractionation pH. With decreasing pH of lignin solution, the zeta potential of lignin particle was increased while lignin molecular weight reported to decrease (Table 4). They also reported larger particle size for fractions separated from lower pH values (with lower molecular weight). These results indicate the role of higher zeta potential at lower pH on the lignin particles coagulation.
    Table 6. Liquid-Lignin Fractions Obtained by pH-Based Fractionation Process (Softwood Kraft Lignin with pH of 13.6 Was Used as Starting Liquid)*”
    H LIGNIN FRACTIONATION USING ORGANIC SOLVENTS/WATER MIXTURE Table 7. Hansen Solubility Parameters for Solvents””
    Table 8. Properties of Ethanol Organosolv of Hardwood Lignin Fractions Using THF/Water Solution®®
    Table 12. Weight-Average (M,,) and Number-Average (M,,) Molecular Weights and Polydispersity (M,,/M,,) of the Eucalyptus Kraft-AQ Lignin Fractions’® Table 11. Yields of the Soluble Fraction (X,,,) and Average M,, and Polydispersity of the Soluble and Insoluble Fractions of Softwood Kraft Lignin in the Different Solvents, as Measured by SEC in DMSO/LiBr*
    Table 13. Yields and Average Molecular Weights (M,, M,,) and Polydispersity (M,,/M,,) of Each Lignin Fraction®
    with higher Hildebrand solubility parameters indicated lignin fractions with higher associated hemicelluloses and higher content of noncondensed syringyl/guaiacyl units. Moreover, small amounts of beta-aryl ether linkages (-O-4) were survived from the kraft-AQ pulping. Different alcohols, keto, and ester solvents for softwood kraft lignin fractionation have been investigated.*°** The solubility parameters of solvents with fractionated lignin properties were reported. With increasing solubility parameter, more lignin was dissolved. Table 11 indicates polydispersity and average M,, of the soluble and insoluble fractions in the different solvents. All soluble fractions indicated lower molecular weight than insoluble fractions.
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    Extraction of Metal Ions by ELM Separation Technology
    by Mohd Ali Hashim

    2012, Journal of Dispersion Science and Technology

    The removal of toxic heavy metal ions is of great concern in the environmental field. Emulsion liquid membrane (ELM) technology has been proposed for the separation processes to enhance the extraction process and reduce the solvent and... more
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    Green production of bio-ethanol from cellulosic fiber waste and its separation using polyacrylonitrile-co-poly methyl acrylate membrane
    by AHMED E M A D MANSY
    The world is currently suffering substantially from the over-use of fossil fuels and worsening global climate change. The recycling and conversion of various types of biomass wastes for production of bio-ethanol have recently received... more
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    Separation of BTEX aromatics from n-octane using a (tetrabutylammonium bromide + sulfolane) deep eutectic solvent-experiments and COSMO-RS prediction
    by Mohd Ali Hashim

    2014, RSC Advances

    Separation of aromatics from aliphatics is a challenging process because of the close range of their boiling points and the formation of several combinations of azeotropes. Until now, no feasible separation process is available for... more
    Fig.1 Ternary phase diagram for n-octane + aromatic + DES at 25C. The full symbols and solid lines represent experimental data, empty circles and dotted lines represent NRTL correlation, triangles and dashed lines represent COSMO-RS prediction. (a) DES + toluene + n-octane, (b) DES + m-xylene + n-octane, (c) DES + benzene + n-octane, (d) DES + ethylbenzene + n-octane.
    Fig. 3 Distribution ratio for the ternary systems. Symbols represent experimental data; lines represent COSMO-RS prediction. Diamonds and solid line for DES + toluene + n-octane, squares and dashed line for DES + m-xylene + n-octane, triangles and dotted line for DES + benzene + n-octane, circles and dot-dashed line for DES + ethyl- benzene + n-octane.
    Fig. 2. Selectivity for the ternary systems. Symbols represent experi- mental data; lines represent COSMO-RS prediction. Diamonds and solid line for DES + toluene + n-octane, squares and dashed line for DES + m-xylene + n-octane, triangles and dotted line for DES + benzene + n-octane, circles and dot-dashed line for DES + ethy! benzene + n-octane.
    Fig. 4 o-Profile and cosmo cavities for each species involved in this study. The vertical dashed lines indicate the threshold for hydrogen bond interaction energy, where peaks at ¢ >+0.0084 e A~? indicate the presence of a hydrogen bond acceptor group in the species, and peaks at ¢ <—0.0084 e A~? indicate the presence of a hydrogen bond donor group in the species.
    Fig.5 o-Profiles for each species involved in this study where the DES is taken as a mixture. The vertical dashed lines indicate the threshold for hydrogen bond interaction energy, where peaks at ¢ >+0.0084 e A-? indicate the presence of a hydrogen bond acceptor group in the species, and peaks at o <—0.0084 e A~ indicate the presence of a hydrogen bond donor group in the species.
    Table 2 Composition of the experimental tie-lines (in mole fractions) and values of the distribution coefficient (D) and selectivity (S) for the ternary system m-xylene (1) + n-octane (2) + DES (3) at P=1atm and T = 25°C
    Table 1 Composition of the experimental tie-lines (in mole fractions) and values of the distribution ratio and selectivity for the ternary system toluene (1) + n-octane (2) + DES (3) at P=1atmand T= 25°C The linearity of each plot indicates the degree of consistency of the data. The parameters of the Othmer-Tobias and Hand correlation are given in Table 5. The regression coefficients R? are very close to unity which indicates the degree of consistency of our experimental data.
    Table 4 Composition of the experimental tie-lines (in mole fractions) and values of the distribution coefficient (D) and selectivity (S) for the ternary system ethyl benzene (1) + n-octane (2) + DES (3) at P= 1 atm and T = 25°C
    Table 3 Composition of the experimental tie-lines (in mole fractions) and values of the distribution coefficient (D) and selectivity (S) for the ternary system benzene (1) + n-octane (2) + DES (3) at P= 1 atmand T = 25°C
    Table 5 Parameters for Othmer—Tobias and Hand correlations As can be seen, the interaction between n-octane and the DES was considered independent of the aromatic compound.
    Table 6 Comparison of selectivity and distribution ratio with other solvents reported in the literature
    Table 7 RMSD for the calculated ternary LLE diagram with NRTL and COSMO-RS
    Table 8 NRTL parameters for the ternary systems (aromatic + n- octane + DES) Fock level and 6-31G* basis set. The calculation of geometry optimization at the Hartree-Fock level gives more meaningful and accurate values,” while the 6-31G* basis set accounts for the polarization effect of the species in the complexes. From the optimized geometry for each individual species, a single point calculation was performed with activation of cosmo file genera- tion using density functional theory with a Becke-Perdew functional and triple zeta valence potential (TZVP) basis set. All of these jobs were performed with Turbomole Software Package.” Thereafter, the cosmo files were imported into COS- MOthermX software package with the parameterization file BP_TZVP_C30_1301.ctd.** The o-profiles, o-potentials, and the ternary liquid-liquid equilibrium phase diagram were retrieved from COSMOtherm<x software.
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    Adsorption of eriochrome black T from aqueous phase on MgAl-, CoAl-and NiFe-calcined layered double hydroxides: Kinetic, equilibrium and thermodynamic studies
    by Mukarram Zubair and 
    1 more
    Muhammad Daud
    This work reports the synthesis of MgAl-, CoAl-and NiFe-layered double hydroxides (LDH) with mole ratio of 3:1 via co-precipitation method and calcination at 350 °C under nitrogen for 2 h. The resultant calcined LDHs (CLDHs) were used for... more
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    Evaluation of Thermophysical Properties of Imidazolium-Based Phenolate Ionic Liquids
    by M.I. Abdul Mutalib and 
    1 more
    Syed Shah
    Thermophysical properties of imidazolium-based phenolate ionic liquids (ILs) were investigated over a wide temperature range. Different alkyl groups such as ethyl, butyl, hexyl, octyl, and decyl were tethered to the 1-methylimidazolium... more
    Figure 3. Plot of log(7) as a function of temperature: <<, [C,mim][Phe]; ll, [C,mim][Phe]; @, [C,mim][Phe]; A, [C,mim]- [Phe]; and VW, [C,pmim][Phe].
    Viscosity Measurement. An Anton Paar viscometer was used to perform the viscosity measurement in a temperature range from 293.15K to 373.15K. An increase in temperature decreased the viscosity. The viscosity versus temperature data are tabulated in Figures 2 and 3 and Table 1 in the Supporting Figure 2. Experimental viscosity of ILs as a function of temperature: <q [C.mim][Phe]; ™, [C,mim][Phe]; @, [C,mim][Phe]; A, [Cgmim][Phe]; and V,[C,,mim][Phe].
    Figure 5. Surface tension as a function of temperature: <<, [C,mim][Phe]; Ml, [C,mim][Phe]; @, [Cgmim][Phe]; A, [C,mim]- [Phe]; and W,[C,omim][Phe].
    Table 4. Thermal Decomposition Temperature (T,), Glass Transition Temperature (T,), Water Content, and Halide Content in ILs Figure 6. TGA profile for synthesized ILs: [C,mim][Phe], [C,mim]- [Phe], [Cgmim][Phe], [Cgmim][Phe], and [C,pmim][Phe].
    Refractive Index. The refractive index data for the phenolate ILs is presented in Figure 8 and Table 7 in Supporting Information. An increase in chain length decreases the refractive index. The refractive index decreases in the order
    Industrial & Engineering Chemistry Research Figure 7. Specific heat capacity as a function of temperature: <, [C,mim][Phe]; ll, [Cymim][Phe]; @, [C,mim][Phe]; A, [C,mim]- [Phe]; and W, [C,pmim][Phe].
    Table 1. Calculated Values of Volume Properties of ILs at 303.15 K Surface Tension. The surface tension values of the phenolate-based ILs were recorded in a temperature range from 293 to 353 K and are shown in Figure 5 and Table 4 in Supporting Information. The surface tension showed a linear relationship with temperature as in the case of density and viscosity. Among the synthesized ILs, [C,mim][Phe] has the highest surface tension, while [C,)mim][Phe] showed the lowest surface tension. The surface tension decreased with the increase in the alkyl spacer length of the cation and followed the order [C,mim][Phe] > [C,mim][Phe] > [C,mim][Phe] > [Cgmim][Phe] > [C,)mim][Phe]. The surface tension of phenolate ILs is lower than that of water (71. 98 mN-m7') but higher than that of organic solvents such as methanol (22.07 mN-m7!), acetone (23.5 mN-m7!), and n-alkanes.°~*° The surface tension of [C,mim][BF,], [C,mim][BF,], and group has the highest density (1.2816 g-cm™’), and the lowest density of 1.0825 g-cm™! was observed for [C,)mim][Phe]. The density of [TMG][Phe] (1.03468 g-cm™! at 293.15 K) is lower than that of all the imidazolium-based phenolate ILs at similar conditions.” The [C,mim] (n = 4—8) ILs with [T£,N] ~ and [PF,] anions have density higher than that of phenolate ILs. The density of [ Cymim][T£,N] is in the range of 1.5197— 1.5260 g-cm™, and [C,mim][PF,] is solid at 293.15 K308788 The density of [C,mim][Phe] is 1.2816 g-cm™ at similar conditions. [C,mim][BF,] (1.2479 g-cm™) showed a density lower than that of their phenolate counterpart (1.2816 g-cm™) at 293.15 K.*° The densities of [C,mim][Tf£,N] and [C,mim]- [PF,] are 1.4402—1.4427 g-cm™ and 1.3698—1.3727 g-cm™?, respectively, at 293.15 K.°°°*°? In similar conditions, the density of [C,mim][BF,] was reported to be 1.1200—1.2077 g- m7>,'°-* while the density of [ Cymim][Phe] is 1.2199 g- cm™*. When the alkyl spacer length increased to C6, the density of [Cgmim][Phe] (1.1652 g-cm ~3) and the density of [Csmim][BF,] (1.1531 g-cm ~*) became comparable at 293.15 K.*° The densities of [Cgmim][PF,] and [ Cgmim]- [Tf,N] are higher than that of their [Phe]~ anion analogues.°?°7*9 The [BF,]~ ILs with C8 and C10 carbon atoms also showed density data value eemipamble with that of [Cgmim][Phe] and [ C,mim][Phe].°° The densities of [ Cgmim][Tf£,N] and [ C,) mim][T£,N] are higher than that of their [Phe]~ analogues.°”°°** [Cgmim][PF,] showed a density higher than that of [Cgmim][Phe], and [C,)»mim][PF,] is solid at 293.15 K, while [C,»mim] [Phe] has density of 1.0825 g-cm™ at 293.15 K.°°
    Table 2. Surface Thermodynamic Functions of Pure ILs at 303.15 K* values are in agreement with other classes of imidazolium-based ILs. This is because of the high surface orientation and more structured liquid phase in ILs. The surface enthalpy value of the ILs is very close to that of common organic solvents such as octane (51.1 mJ-m~”) and benzene (67 mJ-m~”), and the values decrease with an increase in the chain length, which is in agreement with previous observations.°”” This may be because of the lower hydrogen bond interaction with the increase in chain length.
    Table 5. Values of Parameters of ILs for the Interstice Model at 303.15 K
    Table 3. Critical Temperature (T.), Normal Boiling Temperature (T,,), and Enthalpy of Vaporization (A{Hf,) of ILs at 303.15 k (—SO °C) and [Cymim][PF,] (—58 °C) have glass transition temperatures comparable with that of [C,mim][Phe].
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    Working principle and application of magnetic separation for biomedical diagnostic at high and low field gradients
    by Yeap Swee Pin
    Magnetic separation is a versatile technique used in sample preparation for diagnostic purpose. For such application, an externalmagnetic field is applied to drive the separation of target entity (e.g. bacteria, viruses, parasites and... more
    Figure 1. (a) Sample with a mixture of various components containing both target and non-target entities, (b) isolation of target entities using magnetic field, (c) concentrated target after removal of the non-targets. Note that the tar- gets must possess intrinsic magnetic responsiveness, or have been pre-labelled with magnetic responsive particles. (Online version in colour.)
    Figure 2. (a) Schematic diagram showing the principle of i-RBC separation from a blood sample using a microfluidic device containing ferromagnetic wire. An external magnetic field was applied normal to the ferromagnetic nickel (Ni) wire in order to create high magnetic field gradient. Paramagnetic i-RBCs were drawn towards the Ni wire and isolated out from the h-RBCs, reprinted with permission from [12], copyright © 2013 American Chemical Society. (b) SK-BR3 cells incu- bated (i) with 10 that had been conjugated with Ab (dark blue), and (ii) with carboxyl-functionalized 10 that had not been conjugated with Ab (/ess blue) (note: Prussian blue staining was implemented to confirm the presence of Fe ions on the cell surface), reprinted with permission from [18], copyright 2011 Elsevier. (c)(i) Schematic diagram illustrating a free-flow MS technique at which laminar flow was applied in x-direction, whereas magnetic field was applied in y-direction. Note that the non-magnetic material moved along the laminar flow, while those with magnetic responsiveness were deflected from the direction of laminar flow. This separation technique was used to separate HeLa cells in which HeLa cells that had been incubated with magnetic particles (ii) flowing straight through the channel when there was no applied magnetic field and (iii) deflected in their flow direction upon application of magnetic field, reprinted with permission from [13], copyright © 2006 Royal Society of Chemistry. (Online version in colour.)
    Figure 3. Illustration of HGMS and LGMS processes. (a) The HGMS column is packed with randomly entangled magnetizable wires, which act as magnetic field ‘dehomogenizer’ to produce strong and localized magnetic field gradient near to it. Magnetic particles which are flowing through the column will experience an exceptionally strong magnetophoretic force in the vicinity of the magnetizable wires and be captured on them. (b) Illustration of LGMS process. Permanent magnet is used to create magnetic field gradient across the magnetic particle solution in which magnetic particles are going to be separated. The magnetic particles migrate towards the region with highest magnetic field gradient (which is usually the region adjacent to the magnet) and are separated from the solution. Particle aggrega- tion (due to the magnetic dipole — dipole interaction) and continuous circulating flow (as a consequence of hydrodynamic effect) occur throughout the entire process and contribute to the distortion of the magnetophoretic pathway of magnetic particles. (Online version in colour.)
    Figure 4. (a) MP;9 was separated in 1 min by using magnetic field of 0.01 T. Meanwhile, MP3) remains well dispersed even after 60 min subjected to the same magnetic field, reprinted with permission from [22], copyright 2015 American Chemical Society. (b) Optical micrographs of solution with 1g ml! of 0.41 yum superparamagnetic microsphere (Estapor® M1-—030/40) are demonstrated in (i) and (ii). Figure (i) was observed under the absence of magnetic field, while figure (ii) is the image taken after 120 s of magnetic field exposure. The alignment of superparamagnetic microsphere along the magnetic field was observed in (ii) and this is an indication of magnetic particle aggregation under low gradient magnetic field, reprinted with permission from [48], copyright © 2008 American Chemical Society. Optical micrograph of 425 nm magnetic nanoparticles in deionized water (iii) before the application of magnetic field and (iv) a few seconds after the exposure to magnetic field generated by NdFeB magnet, reprinted with permission from [45], copyright © 2008 American Institute of Physics Publishing LLC. Chain formation (particle aggregation) was observed in (iv) and this phenomenon has proven the occurrence of cooperative magnetophoresis. (c) The magnetophoresis profile for (i) Estapor® M1—030/40 particles, reprinted with permission from [48], copyright © 2008 American Chemical Society, and (ii) 30 nm bare iron oxide magnetic nanoparticles, reprinted with permission from [58], copyright © 2014 American Chemical Society. Both (i) and (ii) show that the magnetophoresis process is accelerated as magnetic particle solution with higher concentration is employed. The variation of magnetophoresis rate with the concentration of the magnetic particle solution indicates the significance of particle aggregation throughout the magnetophoresis. (d) Illustration of magnetic separation chamber used for the fractionation of mouse macrophages or human ovarian cancer cells (HeLa cells) according to the cell magnetic moment, reprinted with permission from [13], copyright © 2006 Royal Society of Chemistry. (Online version in colour.)
    Figure 5. (a) A pictorial drawing (not drawn to scale) showing membrane of a target cell labelled with magnetic particles of various sizes (more nano-sized magnetic particles can be attached on the cell surface than the micrometre-sized counterparts due to less steric exclusion) [18]. (b)(i) Transmission electron microscopy image showing F. coli immobilized with 3-mercaptophenylboronic acid/1-decanethiol-modified magnetic nanoparticles, reprinted with permission from [64], copyright © 2013 Multidisciplinary Digital Publishing Institute; (ii) electron micrograph (scale bar, 5.14 tum) of £. coli 0157:H7 cells captured by Dyna- beads® M-280 Streptavidin (Dynal, Lake Success, NY, USA) coated with biotinylated antibodies, reprinted with permission from [65], copyright © 2002 John Wiley and Sons. (c) Solution with well-dispersed magnetic particles provides high 7, value. Once the target cell was mixed with the magnetic particle solution, interaction between antibody (from the functionalization layer of magnetic particles) and antigen (from the target cells) would induce the aggregation between magnetic particles and cells which results in large magnetic particles—cells complex. Owing to the presence of the larger-sized complex, 7 value of the solution becomes lower, reprinted with permission from [61], copyright © 2009 American Chemical Society. (d) Variation of 7, value with the number ratio of target cells to magnetic particle probes, reprinted with permission from [61], copyright © 2009 American Chemical Society. (e) The effect of magnetic particle (MP3) concen- tration (0.1, 0.5, 1 and 10 ug ml~') on the sensitivity of the detection process. It can be observed that the sensitivity (change of 7 value) of the detection method is decaying with the concentration of MP39, reprinted with permission from [22], copyright © 2015 American Chemical Society. (Online version in colour.)
    Figure 6. Schematic diagram demonstrating the relationship between the three major factors (particle size, particle concentration and magnetization) that influence the performance of LGMS-aided biomedical diagnosis. Image components reprinted with permission from [13], Copyright © 2006 Royal Society of Chemistry, [22 Copyright © 2015 American Chemical Society, [45] Copyright © 2008 American Institute of Physics and [48] Copyright © 2008 American Chemical Society (Online version in colour.)
    “Magnetic particles that were used to label on target entity which is originally non-magnetically responsive. >A y = net magnetic susceptibility of the RBC in aqueous suspension= Xpec— Xy,0+ ‘Saturation magnetization. “The values of magnetic field strength and magnetic field gradient provided were the maximum (which occurs at the location closest to the magnet within the whole domain of flowing channel) under th “simulation based on the geometry configuration provided by using COMSOL Multiphysics (see electronic supplementary material for the simulation result). ‘Magnetic moment. 91 pg = 8 x 10° nanoparticles. "The carboxylate functional groups here are to stabilize the magnetic particles in aqueous medium. The concentration of magnetic beads is estimated in the solution where magnetic separation occurs. IDring iIMmunamacnetic Jahelling the ctrantavidin-coated micrnheadc were mived with hacterial call< that already nre-treated with hiatinvlated anti FE coli antihndiac
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    Modeling and optimization of an industrial ammonia synthesis unit: An exergy approach
    by Daniel Flórez-Orrego
    An exergy modeling and optimization of an industrial ammonia unit based on steam methane reforming (SMR) process is presented. The base-case unit produces about 1000 t NH3/day [1], as well as power and steam, with no auxiliary exergy use.... more
    Fig. 1. Flowsheet of the ammonia production unit. following sections, the process balances, exergy efficiency defini- tions and the optimization methodology are presented.
    Fig. 10. Exergy destruction in the ammonia loop as a function of the catalytic bed inlet temperatures T; and T3 (Loop pressure: 200 bar)
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    The Impact of MOF Feasibility to Improve the Desalination Performance and Antifouling Properties of FO Membranes
    by Mostafa Dadashi Firouzjaei
    In this study, a hydrophilic metal-organic framework (MOF) was applied to improve the performance of cellulosic membrane for forward osmosis (FO) desalination application. The characterization results confirmed that the MOF particles... more
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    Agglomeration, colloidal stability, and magnetic separation of magnetic nanoparticles: collective influences on environmental engineering applications
    by Yeap Swee Pin
    Magnetic nanoparticles (MNPs) which exhibit magnetic and catalytic bifunctionalities have been widely accepted as one of the most promising nanoagents used in water purification processes. However , due to the magnetic dipole-dipole... more
    besides providing enormous rooms for degradation of pollutants, MNPs simultaneously work as carrier/ vehicle to bring the pollutants (which usually are non- magnetic) out of the aqueous environment. An interest- ing article published in 2006 by Yavuz et al. demon- strated the successful purification of arsenic- contaminated water using MNPs. According to their finding, it is possible to separate these nano-sized parti- cles by just applying a low magnetic field gradient (Yavuz et al. 2006). This exciting result has opened up a new gateway into the application of MNP as a mag- netic carrier for water purification processes. To date, MNPs have been actively used for the separation of various types of pollutants, such as heavy metal ions (Zargoosh et al. 2013; Yavuz et al. 2006; Zhang et al. 2009), radioactive wastes (Kaur et al. 2013), colorants
    Fig.3 a Time lapse in situ micrographs showing agglomeration kinetics of nano-scaled iron nanoparticles (scale bar 25 um). b Two regimes of agglomeration [Reprinted with permission from Phenrat et al. (2007). Copyright (2007). American Chemical Society]
    Fig.4 Various strategies to enhance dispersion stability of MNPs. (The inset photo showing nanoparticle suspension stabilized by guar gum was reprinted with permission from Sakulchaicharoen et al. (2010). Copyright (2010). Elsevier)
    Fig. 5 Illustrations show the difference between a HGMS and b LGMS setups [Reprinted with permission from Leong et al. (2016). Copyright (2016). The Royal Society]
    Fig. 6 a-d Magnetic alignment and magnetic drifted motion of MNPs under magnetic field gradient. The magnetic field gradient was generated by a magnetic source. (The inset optical photos show the magnetic alignment of magnetic nanorod clusters reprinted with permission from Lim et al. (2014a). Copyright (2014). Elsevier)
    into two types, namely, cooperative and noncooperative magnetophoresis (Andreu 2013). For the cooperative
    Fig. 8 a A clump of MNPs undergoes cooperative-type magnetophoresis. b Individual MNPs undergo noncooperative- type magnetophoresis PISULY O MUSUAdWWys VUUUL LY Pes Ul LAS MelLOVUULesls. Since MNPs move together during cooperative magnetophoresis, the synergistic magnetophoretic velocity is higher (Faraudo and Camacho 2010; De Las Cuevas et al. 2008). For noncooperative magnetophoresis, singly dispersed MNPs move much slower. For instance, at similar particle concen- tration (10 g/L) and magnitude of magnetic field gradient (30 T/m), De Las Cuevas et al. showed that while undergoing cooperative magnetophoresis, their particles only took < 100 s to achieve full separation (De Las Cuevas et al. 2008), while Andreu et al. found that their y-Fe.03 nanocrystals took ~ 2 x 10° s to be fully magnetically separated under the noncooperative mode (Andreu et al. 2011b). In
    Fig. 9 a Magnetophoresis separation time vs. concentration of particle suspension for bare Fe3Oy, (filled circle) and PSS 70k/ Fe3O, particles (filled diamond) [Reprinted with permission from Yeap et al. (2014) Copyright (2014). American Chemical Society]. b i: Magnetophoresis profiles of citric acid-coated magnetic
    particles under various medium pH; ii: zeta potential of the parti- cles at various medium pH values [Reprinted with permission from Benelmekki et al. (2011) Copyright (2011). Springer Science + Business Media] In order to further reveal the underlying mechanism that governs the magnetophoresis of both bare Fe3;04 and PSS 70k/Fe3O, particles, our work was continued with a mechanistic examination on the transient magnetophoresis profile (Yeap et al. 2014). From our observation, the magnetophoresis kinetic profile of the PSS 70k/Fe30, particles was obviously different from PSS 70k/Fe3O, particles was obviously different from
    Fig. 10 Dark field scattering images for PEG-modified iron oxide nanoparticles exposed to external magnetic field (Saville et al. 2013 [licensed under a Creative Commons Attribution 3.0 Unported Licence] On the other hand, Benelmekki et al. investigated the magnetophoresis profile of citric acid-modified magnetic particles in a horizontal low-gradient magnetic field (Benelmekki et al. 2011). They found that the magnetophoresis profile was in fact affected by the pH of the suspension itself. As shown in Fig. 9bi, for particles at pH 4.62 and pH 6.72, there were two pla- teaus in the opacity decay indicating two stages of particle agglomeration during the cooperative magnetophoresis. Such phenomenon was in line with the multimodal zeta potential distribution obtained at these two pH values (Fig. 9bii), suggesting that the particles with lower zeta potential were isolated first, followed by the ones with higher zeta potential. Obvi- ously, the zeta potential of the particles, which deter- mines the magnitude of electrostatic stabilization, pro- vided substantial influence on the magnetophoresis be- havior as well. This result is consistent with our argu- ment, in which particles with high zeta potential value
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    Green solvents for sustainable separation processes
    by Thomas Brouwer and 
    1 more
    Lisette Sprakel

    2019, Green solvents for sustainable separation processes

    Solvent-based separation processes can reduce the required energy input for separation, improve biocompatibility, and allow for mild responsive separation systems that are applicable when distillation is technically not feasible because... more
    Figure 1 Schematic overview of countercurrent liquid—liquid extraction process (ce), where two liquid phases are in equilibrium (a). Dimensioning of such pro- cesses requires proper equilibrium description, for which ternary diagrams are illustrative (d). Stimuli responsive solvents may be applied to facilitate mild solvent regeneration (b).
    The schematic representation of (a) micellization by sodium dodecylsulphate and (b) the formation of a hydrotrope by 1-butyl-3-alkylimidazolium, surrounding ursolic acid. The blue and red areas on the solvent molecules indicate a polar and apolar functional group, respectively.
    Figure 3 Required column heights for CO capture with several ILs in perspective. Reproduced from Ref. [26]**—Published under Creative Commons license | The Royal Society of Chemistry.
    Figure 4 Examples of molecules that are frequently applied in DESs. Often they are designated as hdyrogen bond acceptor (HBA) or as hydrogen bond donor (HBD), but many can be both donating and accepting hydrogen bonds.
    Figure 5 Examples and circularity of sustainable, nature-derived solvent systems. ATPS, aqueous two-phase system; NADES, natural deep eutectic solvent; MMC, methyl(2,2-dimethyl-1,3-dioxolan-4-yl)methy! carbonate.
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    Impact of straight, unconnected, radially-oriented, and tapered mesopores on column efficiency: A theoretical investigation
    by Fabrice G E Gritti
    Solid–liquid mass transfer resistance due to diffusion a b s t r a c t Superficially porous particles (SPPs) can be prepared from a pseudomorphic transformation (PMT) which produces straight, unconnected, and radially-oriented mesopores... more
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    Phase diagrams of aqueous biphasic systems composed of ionic liquids and dipotassium carbonate at different temperatures
    by Sepandar Malekghasemi

    Fluid Phase Equilibria

    Phase diagrams of the {1-butyl-3-methylimidazolium nitrate ([Bmim][NO 3 ])/1-hexyl-3-methylimidazolium nitrate ([Hmim][NO 3 ]) þ dipotassium carbonate (K 2 CO 3)} aqueous biphasic systems (ABS) and the binodal curves of... more
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    Activity coefficients at infinite dilution for solutes in the trioctylmethylammonium bis(trifluoromethylsulfonyl)imide ionic liquid using gas–liquid chromatography
    by Nirmala Deenadayalu

    2010

    In this work, we report the infinite dilution activity coefficients (γ 1,2 ∞ ) of 39 to 43 diverse organic solutes dissolved in three 1-alkyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquids (IL) homologues bearing... more
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    Sorption of ionic dyes onto untreated low-rank coal – oxihumolite: A kinetic study
    by Pavel Janos

    2007, Dyes and Pigments

    The kinetics of the sorption of basic dyes e Methylene Blue (C.I. Basic Blue 9), Malachite Green (C.I. Basic Green 4), Rhodamine B (C.I. Basic Violet 3), Crystal Violet (C.I. Basic Violet 10) e as well as acid dyes e Egacid Orange (C.I.... more
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    Thermophysical properties ofaqueous N -methyldiethanolamine(MDEA) and ionic liquids1-butyl-3-methylimidazoliumtrifluoromethanesulfonate[bmim][OTf],1-butyl-3-methylimidazolium acetate[bmim][Ac]hybridsolvents for CO 2 capture
    by Sintayehu Mekuria (PhD) Hailegiorgis (PhD)

    2017, https://www.sciencedirect.com/science/article/pii/S0167732217327630

    In this research work, thermophysical properties such as density, refractive index,surface tension, and viscosity of aqueous N-methyldiethanolamine (MDEA) and1-butyl-3-methylimmidazolium trifluoromethanesulfonate [bmim][OTf],... more
    increase the volume between the molecules of the solvent. The increased volume with the increase in the temperature decreased the density of the hybrid solvents. It was also observed that with the increase in the concentration of the ature may cause the reduction of the hydrogen bonding between the imidazolium ring and the anion part of the ionic liquid (Jacquemin et al., 2006). This reduced forces of attraction between the molecules create the voids spaces and
    Fig. 4 - Effect of temperature on refractive index of aqueous solution of 30 wt% MDEA and [bmim][Ac] for various wt% concentrations: @, 0; M, 5; 4, 10; a, 15; kK , 20; dark lines, calculated using Eq. (2). ture data for the reproducibility of the work. Average absolute deviation (% AAD) was also given in Table 1 to compare the present results to determine the deviation percent with the results reported in literature. Low % AAD data confirmed the reproducibility of the work. The overall viscosity data of the aqueous solution of the N-methyldiethanolamine (MDEA) and ionic liquids 1-butyl-3-methylimidazolium trifluoromethane- sulfonate [bmim][OTf], 1-butyl-3-methylimidazolium acetate [bmim][Ac] hybrid solvent were presented as Supplementary data in Table S4 and shown in Figs. 7 and 8, respectively. From the experimental data, it was observed that the viscosity of all samples have temperature and ionic liquids concentra- tion dependent behavior throughout the experiments. With the increase in the concentration of the ionic liquids, the vis- cosity of the hybrid solvent increased. The increased viscosity of the solvent was due to presence of the hydrogen bonding As presented in Table 1, the viscosity data of 1-butyl-3- methylimidazolium trifluoromethanesulfonate [bmim][OTf] and pure MDEA were measured and compared with litera-
    Fig. 5 - Effect of temperature on surface tension of aqueous solution of 30 wt% MDEA and [bmim][OTf] for various wt% concentrations: @, 0; M, 5; 4, 10; a, 15; >K , 20; dark lines, calculated using Eq. (2).
    Fig. 6 - Effect of temperature on surface tension of aqueous solution of 30 wt% MDEA and [bmim][Ac] for various wt% concentrations: @, 0; M, 5; 4, 10; a, 15; >K , 20; dark lines, calculated using Eq. (2). In the past research studies the experimental data of the density, refractive index and viscosity were correlated using in the ionic liquid and between the ionic liquid and solvent as well (Yusoff et al., 2013). When the organic molecules are mixed with imidazolium based ionic liquids forces of attrac- tion were found between the solute and the imidazolium ring of the ionic liquids (Buchheit and Baltus, 2006; Geng et al., 2008). The viscosity of the solvent decreased when the hydro- gen bonding between the imidazolium ring and the anion part of the ionic liquids were weaken. It was observed that with increase in temperature, viscosity data of all the samples were decreased at any fixed composition of the solvents. Due to the increase in temperature, the hydrogen bonding decreased between the imidazolium ring and anion part of the ionic liq- uid. Furthermore, the forces of attraction between the organic solvent (MDEA) and the imidazolium ring of the ionic liquid were also reduced. The quantity of the water also have a signif- icant effect on the viscosity of the solution. Seddon et al. (2000) reported that the water accommodate in the salt-rich region
    Fig. 7 - Effect of temperature on viscosity of aqueous solution of 30 wt% MDEA and [bmim][OTf] for various wt% concentrations. @, 0; M, 5; 4, 10; a, 15; kK , 20; dark lines, calculated using Eq. (6).
    the equation as a function of temperature only at various concentrations of the solvents (Shaikh et al., 2015). Ina recent times, many researchers have correlated the thermophysical properties data as a function of the temperature and concen- tration of the solvents as well (Garg et al., 2016c; Navarro et al., 2014). The correlation of the experimental data is a fast and reliable mathematical formulation which allows to interpo- late the experimental points by using the empirical equations, while the other side of the picture depicts some drawbacks (as for instance extrapolation). The empirical equation used by many researchers (Garcia et al., 2015; Garg et al., 2016c; Navarro et al., 2014) to correlate the experimental data of the density and refractive index as a function of temperature and the concentration of the solvent, is given in Eq. (1): Fig. 8 - Effect of temperature on viscosity of aqueous solution of 30 wt% MDEA and [bmim][Ac] for various wt% concentrations: @, 0; M, 5; 4, 10; a, 15; kK , 20; dark lines, calculated using Eq. (6). However in the present study the aqueous solution of hybrid solvent consists of ionic liquid (ILs) and amine. In order to investigate the effect of the concentration of both (ILs and amines) on the thermophysical properties of the hybrid sol- vent Eq. (1) was further modified and investigated by Garg et al. (2017) in their research work. The modified Eq. (2) is written as:
    where, w, is the weight percent of ionic liquid; w2 is used for the weight percent of amine and T represent the absolute temperature of the system. related data of all the properties were in good agreement with the experimental data. Table 3 — Fitting parameters for viscosity calculated from Eq. (4).
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    Ultrasonic assisted micro solid phase extraction of arsenic on a new ion imprinted
    by alireza taheri

    2019, Ultrasonics - Sonochemistry

    Pickering emulsion polymerization has been employed for the Ultrasonic assisted-micro solid phase extraction (UA-µSPE) of ultra trace arsenic species by a new magnetic ion imprinted polymer (MIIP) prior to hydride generation atomic... more
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    Achieving quasi-adiabatic thermal environment to maximize resolution power in very high-pressure liquid chromatography: Theory, models, and experiments
    by Fabrice G E Gritti
    A cylindrical vacuum chamber (inner diameter 5 cm) housing a narrow-bore 2.1 mm × 100 mm column packed with 1.8 m HSS-T 3 fully porous particles was built in order to isolate thermally the chromato-graphic column from the external air... more
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    Adsorptive Removal of Thorium(IV) from Aqueous Solutions Using Synthesized Polyamidoxime Chelating Resin: Equilibrium, Kinetic, and Thermodynamic Studies
    by hamid heshmati
    In this study, an amidoximated chelating ion exchange resin was prepared by poly-acrylonitrile (PAN) grafted potato starch. The adsorbent characterizations such as specific surface area, pore volume, average pore radius, and Fourier... more
    descriptionView Paper
    Preparation of polymer electrolyte membranes for lithium batteries by radiation-induced graft copolymerization
    by Mohamed Nasef and 
    1 more
    Khairul Zaman

    2004, Solid State Ionics

    Polymer electrolyte membranes with different degrees of grafting were prepared by radiation-induced graft copolymerization of styrene monomer onto poly(vinylidene fluoride) (PVDF) films and subsequent chemical activation with liquid... more
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    Processes associated with ionic current rectification at a 2D-titanate nanosheet deposit on a microhole poly(ethylene terephthalate) substrate
    by Christian Harito

    2019, Journal of Solid State Electrochemistry

    Films of titanate nanosheets (approx. 1.8-nm layer thickness and 200-nm size) having a lamellar structure can form electrolyte-filled semi-permeable channels containing tetrabutylammonium cations. By evaporation of a colloidal solution,... more
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    Multicomponent adsorption in mesoporous flexible materials with flat-histogram Monte Carlo methods
    by Nathan Mahynski
    We demonstrate an extensible flat-histogram Monte Carlo simulation methodology for studying the adsorption of multicomponent fluids in flexible porous solids. This methodology allows us to easily obtain the complete free energy landscape... more
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    Model Performances Evaluated for Infinite Dilution Activity Coefficients Prediction at 298.15 K
    by Thomas Brouwer

    2019, Model Performances Evaluated for Infinite Dilution Activity Coefficients Prediction at 298.15 K

    The infinite dilution activity coefficient (γ i ∞) is often applied to characterize solvent−solute interactions, and, when accurately predicted, it can also serve as an early-stage solvent selection tool. Ample data are available on the... more
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    A novel core fractionation process of human plasma by expanded bed adsorption chromatography
    by Allan Lihme

    2010, Analytical Biochemistry

    Current plasma fractionation technology combines ethanol precipitation with packed bed chromatography. We have developed a novel core fractionation process comprising five expanded bed adsorption (EBA) chromatographic steps on... more
    Fig. 7. SDS-PAGE analysis of the various column eluates (summary). (A) Nonreduced fractions obtained by EBA chromatography of plasma on columns A and B. Lane 1: eluate column A (undiluted); lane 2: eluate column B (undiluted); lane 3: fibrinogen (Fib) (1 mg/ml); lane 4: fibronectin (Fibnct) (0.2 mg/ml). (B) Lane 1: raw plasma (diluted 30x); lane 2: eluate column C; lane 3: eluate column D; lane 4: eluate 1 column E; lane 5: eluate 2 column E. All eluates are diluted for a one-to-one comparison with the raw plasma. Trf, transferrin; Alb, albumin.
    Protein content in plasma fractions from columns A and B. Note. Process step yields (%) are indicated in parentheses. Ag: antigen Table 1
    IgG mass balance: column C. Table 2
    AAT mass balance: column D.
    HSA mass balance: column E. Table 4
    Fig. 1. Plasma fractionation process scheme by EBA chromatography. Conceptual process scheme for high yield fractionation of human plasma
    Fig. 2. SDS-PAGE analysis. (A) Nonreduced fractions obtained by EBA chromatog- raphy of plasma on column A. Lane 1: raw plasma (diluted 30x); lane 2: flow- through (diluted 30x); lane 3: wash (undiluted); lane 4: eluate (undiluted); lane 5: fibrinogen (1 mg/ml); lane 6: fibronectin (0.2 mg/ml); lane 7: IgG (0.2 mg/ml). (B) Nonreduced fractions obtained by EBA chromatography of column B flow-through. Lane 1: load material (flow-through from column B, diluted 30x); lane 2: flow- through (diluted 30x); lane 3: wash (undiluted); lane 4: eluate (undiluted); lane 5: fibrinogen (1 mg/ml); lane 6: fibronectin (0.2 mg/ml); lane 7: IgG (0.2 mg/ml). The main protein composition of the plasma fractions from col- umn B is shown in Table 1, and the SDS-PAGE patterns are shown
    Fig. 3. SDS-PAGE analysis of the nonreduced fractions obtained by EBA chroma- tography of column C. Lane 1: load material (flow-through from column B); lanes 2 to 6: flow-through fractions; lane 7: pool of run-through fractions; lane 8: wash; lane 9: IgG eluate.
    Fig. 4. SDS-PAGE of the nonreduced fractions from column D. Lane 1: load material (flow-through from column C); lane 2: flow-through fraction; lane 3: AAT; lane 4: eluate from second elution.
    Fig. 6. SDS-PAGE of the nonreduced fractions from column E. Lane 1: load material; lanes 2 to 6: run-through fractions; lane 7: wash; lane 8: HSA eluate; lane 9: transferrin/IgA eluate; lane 10: pool of run-through fractions.
    Fig. 5. SDS-PAGE of AAT purified from column B (lane 1) or incubated at 30 °C for 30 min with 4 ul (lane 2), 8 pl (lane 3), or 12 il (lane 4) of elastase. Lane 5: pure elastase.
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    Photocatalytic Degradation of Naphthalene by Electrospun Mesoporous Carbon Doped Anatase TiO2 Nanofiber Mats
    by Souryadeep Bhattacharyya
    We have fabricated partially aligned free-standing mesoporous pure anatase TiO2 nano fiber mats (TiO2-NF) for photocatalysis by electrospinning on a rotating drum collector using a blend of titanium isopropoxide (Ti(OiPr)4), with a... more
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    Synergistic green extraction of nickel ions from electroplating waste via mixtures of chelating and organophosphorus carrier
    by Raja Norimie Raja Sulaiman

    2017, Journal of Hazardous Materials

    • Synergistic extraction of nickel via LIX63-D2EHPA mixture system. • Maximum synergistic enhancement factor,R Ni , max of 29.56 at X LIX63 = 0.8. • Palm oil as green diluent for synergistic green extraction of nickel. a b s t r a c t The... more
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    Using the fundamentals of adsorption to understand peak distortion due to strong solvent effect in hydrophilic interaction chromatography
    by Fabrice G E Gritti
    The peak distortion observed in hydrophilic interaction chromatography (HILIC) may be caused by the sample diluent to mobile phase mismatch. The United States Pharmacopeia (USP) method for organic impurities in cetirizine HCl tablets... more
    Fig. 1. Experimental peak profile of cetirizine recorded with a 4.6 mm x 100 100 mm 2.5 wm XBridge BEH HILIC column for three different volume fractions of water in the mobile phase: (top chromatograms) 7%; (middle chromatograms) 8%; (bottom chromatograms) 9%. The volume fraction of water in the sample diluent was kept constant at 9%. The injection volume increases from 1 (dark blue) to 2 (orange), 4 (green), 8 (red), 10 (blue), 12 (purple), 16 (cyan), 20 (pink), 30 (yellow), and to 40 wL (brown). The same HPLC system was used. Note the growing distortion of the cetirizine peak profile as the diluent/eluent mismatch and the injected volume increase. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)
    Fig. 2. Scaled USP impurity method for cetirizine HCI tablets run on a 4.6 x 250mm 5 wm XBridge BEH HILIC column (top chromatogram) and a 4.6 x 100mm 2.5 pm XBridge BEH HILIC column (bottom chromatogram). Diluent to eluent mismatch: 9% versus 7% water volume fraction. The indicated injection volume is scaled to the column volume. The indicated flow rate is adjusted to keep the reduced velocity constant. The dilution factors K are equal to 1.23 (top) and 2.05 (bottom) for the HPLC system. The time unit along the x-axis is in minutes.
    Fig. 3. Experimental peak profiles of cetirizine as a function of the injection vol- umes (from 1 to 2, 4, 8, 10, 10.6, 12, 16, 20, 30 and to 40 wL) using two different LC instruments and demonstrating the impact of pre-column sample dispersion on the peak distortion. Diluent to eluent mismatch: 9% versus 7% water volume fraction. (Top chromatograms) HPLC system (115 L dwell injection volume, 120 .L? volume dispersion); (Bottom chromatograms) UHPLC (25 wL dwell injection volume, 35 pL? volume dispersion).
    Fig. 4. Experimental peak profiles of sulfanilamide and four B-blockers (propranolol, metoprolol, nadolol, and atenolol) as a function of the injection volumes (from 1 to 2, 4, 8, 10, 10.6, 12, 16, 20, 30, and to 40 wL) demonstrating the impact on peak distortion of the sample retention relative to the retention of the water excess (vertical dotted purple line). 4.6mm x 100100 mm column packed with 2.5 wm XBridge BEH HILIC particles. Diluent to eluent mismatch: 9% versus 7% water volume fraction. N=20000. Us = 0.212 cm/s for a 2.116 mL/min flow rate. HPLC system. Note that severe peak distortion occurs when the retention time of the analyte is slightly larger than that of the water perturbation. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)
    Fig. 5. Experimental excess (top graph) and total (bottom graph) adsorptior isotherm (295K) of water (solid red lines and full circles) and acetonitrile (solic blue lines and full squares) as a function of the volume fraction of water in the mobile phase. Note that the convention for the Gibbs dividing surface was taker for a hold-up volume Vo equal to 90% of the thermodynamic dead volume Vy. Thi: convention leads to an inflection point with a horizontal tangent slope for a volume fraction of water close to 45%. (For interpretation of the references to color in thi: figure legend, the reader is referred to the web version of the article.) Fig. 5 show the experimental excess (top graph) and total (bot- tom graph) adsorption isotherms of water (red color) and acetoni- trile (blue color) onto the XBridge BEH HILIC adsorbent measured from the MDM experiments at 295 K (see the experimental section for more details). By convention, the arbitrary Gibbs dividing sur- face was taken for a hold-up volume Vo equal to 90% of the thermo- dynamic dead volume Vy =1.24cm3 (or total porosity €;=0.744).
    Fig. 6. Calculated concentration profiles of cetirizine (colored solid lines) and water (solid black lines) on a 4.6mm x 100100 mm XBridge BEH HILIC column (2.5 wm particles) for three different volume fractions of water in the mobile phase (see experimental data in Fig. 1). (Top chromatograms) 7%; (middle chromatograms) 8%; (bottom chromatograms) 9%. The volume fraction of water in the sample dilu- ent was kept constant at 9%. The injection volume increases from 2 (dark orange) to 4 (dark green), 8 (brown), 12 (dark orange), 16 (pink), 12 (purple), 20 (blue), 30 (green), and to 40 wL (red). The column efficiency was set at N= 20000. The superfi- cial linear velocity is us = 0.212 cm/s (2.116 mL/min). The extra-column volume was set at 115 wL (HPLC system). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)
    Fig. 7. Calculated concentration profiles of cetirizine (colored solid lines) and water (solid black lines) regarding the scaled USP impurity method for Cetirizine HCI tablets using the HPLC system (see experimental data in Fig. 2). Diluent-to-eluent mismatch: 9% versus 7% water volume fraction. (Top chromatogram) 4.6 x 250 mm 5 wm XBridge BEH HILIC column, dilution factor K= 1.23. (Bottom chromatogram) 4.6 x 100 mm 2.5 wm XBridge BEH HILIC column, dilution factor K= 2.05.
    Fig. 8. Calculated concentration profiles of cetirizine (colored solid lines) and water (solid black lines) for a series of injection volumes (from 2 to 4, 8, 10, 12, 16, and to 20 wL) on two LC instruments demonstrating the change in peak shape as the injec- tion volume increases. 4.6 mm x 100 100 mm column packed with 2.5 im XBridge BEH HILIC particles. Diluent to eluent mismatch: 9% versus 7% water volume fraction. N=20000. us =0.212 cm/s for a 2.116 mL/min flow rate. (Top graph) HPLC system (115 pL dwell injection volume, 120 pL? volume dispersion); (Bottom graph) UHPLC (15 wL dwell injection volume, 35 L? volume dispersion). Note the sharper bands of water on the UHPLC system responsible for the significant change in peak distortion.
    Fig. 9. Calculated concentration profiles of the analyte (colored solid lines) and water (solid black lines) for a series of Henry’s constant of the analyte (from 0 to 0.27, 0.54, 0.81, 1.08, 1.35, 1.61, 1.88, and to 2.15). 4.6 mm x 100 mm column packed with 2.5 wm XBridge BEH HILIC particles. Diluent to eluent mismatch: 9% versus 7% water volume fraction. N= 20000. us = 0.212 cm/s for a2.116 mL/min flow rate. HPLC system.
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    Equilibrium and Kinetic Studies of Ni (II) Adsorption using Pineapple and Bamboo Stem Based Adsorbents
    by Yennam Rajesh
    This work addresses the preparation and characterization of inexpensive adsorbents for the removal of Ni (II) from aqueous solutions. Activated carbon based adsorbents have been prepared from plant based biomass resources, namely... more
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    Extraction and recovery of toxic acidic components from highly acidic oil using ionic liquids
    by Syed Shah
    Highly toxic naphthenic acid was extracted from highly acidic model oil using ionic liquids. The extraction process required only very low amount of ionic liquids. Extracted naphthenic acid and the ionic liquids used were recovered by... more
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    Liquid–liquid equilibrium data and correlation for quaternary systems of acetic acid + water + methyl acetate + p-xylene at 313.2 K
    by Gregorius Harvianto
    The experimental liquid–liquid equilibrium (LLE) data of the quaternary (acetic acid + water + pxylene + methyl acetate) system was investigated at 313.2 K and atmospheric pressure. This research is aimed to examine the potential of the... more
    Fig. 1. Quaternary diagram of acetic acid (HAc) + water + p-xylene (PX) + methyl acetate (MA) illustrating the mass ratios used at 313.2K for the tie-line measurements.
    Fig. 2. Flow chart of data regression from the LLE experiment to obtain the predicted binary parameters.
    Fig. 4. The selectivity of acetic acid against water (S;2) vs water/acetic acid mass ratio in the initial mixture phase for different ratio of PX to MA (R, to Rs) at 313.2 K and under atmospheric pressure.
    Purity and UNIQUAC parameters of the chemicals used in this work. Table 1
    LLE experimental data (mass fraction), values of the distribution coefficients (D; and D3), and selectivity (S;,2) for the quaternary system, HAc + PX + MA+ Water, at 313.2 K under atmospheric pressure*. * Standard uncertainties u are u(T)=0.1 K, u(p)=1 kPa, u(Wwa)=0.0012, u(Wyac)=0.0021 u(Wpx)=0.0017, and u(Wya)= 0.0015.
    Othmer-Tobias and Bachman correlation parameters of HAc+PX+MA+ Water at 313.2 K for the different mass ratio of PX to MA (PX:MA).
    Binary interaction parameters of NRTL and UNIQUAC models for the quaternary system, water (WA), p-xylene (PX), methyl acetate (MA) and acetic acid (HAc), at T=313.2K.
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    Removal of organic matter and nitrogen in an horizontal subsurface flow (HSSF) constructed wetland under transient loads.
    by Antonio Albuquerque

    2009, Water Science and Technology, 60(7), 1677-1682.

    A monitoring campaign in a horizontal subsurface flow constructed wetland under the influence of transient loads of flow-rate, organic matter, nitrogen and suspended solids showed an irregular removal of COD and TSS and lower both removal... more
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    Recovery of Cenospheres and Fine Fraction from Coal Fly Ash by a Novel Dry Separation Method
    by Witold Zukowski and 
    1 more
    Piotr Czupryński

    2020, Energies 2020, 13(14), 3576

    Aluminosilicate microspheres are a valuable fraction of coal fly ash with diverse applications due to their low density. Currently, there is no efficient and ecologically rational method of cenosphere recovery from fly ash. A combination... more
    Figure 1. Fluidised bed (FB) separation scheme.
    The pneumatic separation was conducted ina specially designed device (Figure 2). The dimensior f the free-fall air chamber were 400 x 100 x 350 mm (length x width x height). The device enabl. artitioning of the feed into fifteen fractions, which further improves the selectivity of the microsphe: ocovery. The airflow in the air chamber of the separator was forced by a vacuum controlled by tk SI 40241 mass flowmeter. During the experiment, the outer air flow was monitored by the Lutro .M-4204 hot-wire anemometer. To ensure uniform flow throughout the entire chamber, a laminé ystem was adopted at both the entrance and the exit of the separating chamber. The FBCs were dose ito the chamber using the plate feeder at a dosing rate of 2, 6 and 3 g/min for the FA;, FA) and FA espectively. Different flow rates were applied to evaluate its influence on the separation efficienc he fly ashes FA, and FA) were similar in terms of granulation, hence a triple increase in feed ra‘ vould substantially increase the overall yield from the apparatus volume. The air flow rates we! pproximately 140 dm?/min, 200 dm?/min and 300 dm?/min for the fine (C), medium-grained (B) an oarse fractions (A), respectively. Its values were adjusted for each granular fraction in the manner th. o material was located neither before nor past the receiver. no material was located neither before nor past the receiver. 2.4. Microsphere Content Determination
    Figure 3. Results of FB separation. Figure 3 presents the results of the first stage of MS recovery using the fluidised bed reactor. It is clearly shown that the bed, during the process, underwent segregation into characteristic layers: the bottom layer included mostly sand particles, the middle layer consisted of coarse fly ash particles and the upper layer contained in the majority char particles. Hence, there are also alternative ways of retrieving the products from the reactor e.g. layer by layer or continuous separation. Fractions obtained in this manner do not need to be subjected to laborious division into grain fractions, directly isolating the activator from the remaining products.
    Figure 4. Fluidised bed concentrates (FBCs) pneumatic separation summary. Table 5. The MS content in the fly ash FA; fractions.
    Figure 5. Diagram of the multistage aluminosilicate microspheres recovery from FA,, Figure 5 shows a diagram of the dry method of MS recovery for the FA; with the water sink—float final step. The diagram includes the sample mass, MS content and the recovery. It can be observed that from 1 kg of FA, containing 0.64 wt.% microspheres, it is possible to recover 5.2 g of cenospheres. Furthermore, only approx. 17 wt.% of the fly ash needs to be subjected to wet separation and eventually becomes waste, while the remaining fly ash can be used in industrial applications in its dry form.
    Table 1. FB separation mass balance, g. Table 2. Share of grain fractions in FBCs—sieve analysis results, wt.%.
    Table 3. The aluminosilicate microspheres (MS) content in the fly ash FA, fractions. Table 4. The MS content in the fly ash FA) fractions.
    Figure 4 also provides information about the mass share of fractions collected in the receiver and he way of grouping them into parts. Pneumatic separation of FBC fractions was performed using a eed rate of 2 g/min for FBB, and 6 g/min for FBC). The increase in feed rate for FBC» fractions led to an infavourable outcome. The first part in coarse fraction (A I) was characterized by the negative value of Newton’s efficiency with relatively high (14%) cenosphere recovery (Table 4). Thus, rejecting of his fraction from further processing led to a significant reduction in the total recovery. Similar issues vere observed for the first part of medium grain fraction (B I) for all FBCs. The explanation of these yutcomes could be a high share of collected material in one or two containers of the receiver, rather han its broad distribution like for fraction A of FBC;. This is one of the main drawbacks of using the
    Table 6. Different variants of the MS recovery dry method. Table 7 depicts a comparison of the obtained results with the data presented in the literature. The Newton’s efficiency of the proposed method and the summarised microsphere recovery are both comparable to the micron separation solution found in the literature. In the case of FA,, the proposed method is slightly advantageous. The scales of the processes significantly differ and the calculated efficiency does not include any losses. However, the fly ash enrichment in the MS for the presented method was satisfactory. The most beneficial was the step with the FB separation. This achieved microsphere recovery at a level of 97-98%, with a 52-55% reduction in the fly ash mass. Current research confirmed previous observations that the utilization of a combination of classifiers in cenosphere recovery form fly ash is not only favourable, but also necessary to obtain high efficiency with an acceptable level of recovery ratio. Six variants of MS recovery were compared for each fly ash type (Table 6). Additionally, values of Rc times n were calculated to emphasise the fact that high values for both parameters were the requirements for effective MS recovery. The first variant, chosen for the purpose of comparison, only involved the screening of the FBCs (71 wm sieve) and excluded the application of the pneumatic separator. This variant was comparable with the variant where the pneumatic separator was used in the case of FBC3, containing the lowest amount of cenospheres. In this trial, pneumatic separation led to an increase in Newton’s efficiency, but the cenospheres recovery was lowered compared to screening. The reason for that were the aforementioned issues with not optimal arrangement of the pneumatic separator. The best variant of MS recovery in terms of Newton’s efficiency proved to be the variant adopting all parts of the FBCs with positive values of Newton’s efficiency.
    4 product share in the FBC. Table 7. Comparison of the proposed MS recovery methods with the data obtained from the literature.
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    Simulation and performance improvement of cryogenic distillation column, using enhanced predictive PengeRobinson equation of state
    by Mohamad Bayat
    In this study, a cryogenic distillation column has been designed and simulated via a computer code based on the theta method of convergence. The required thermodynamic properties are determined from the enhanced predictive Peng-Robinson... more
    Fig. 1. Zero net component flux which leads to bulk equilibrium.
    k-value is a function of the mole fraction, which is unknown in the first iteration. Therefore, to start the solution process, Wilson equation is used to determine K-value which is independent of the vapor-liquid mole fractions: Fig. 2. Schematic of a conventional distillation column with two outlets. 2.1.3. Wilson equation In this method, a number of small groups are defined, based on which we can structurally model a molecule. These groups may have different forms, e.g. CH3 or CH2, which are groups 1 and 2. Some groups are, in fact, a separate independent molecule. For instance, helium and hydrogen are groups 23 and 21. Nevertheless, hydrocarbons like butane (C4H19) and propane (C3Hg) are composed of two group 1 and two group 2, and two group 1 and one Group 2, respectively. To use this equation of state, all these coefficients must be determined for each molecule before the solution.
    First and foremost it is necessary to write the mole balance and phase equilibrium equations for each tray, separately. The main assumptions considered in this work are: the temperature of all trays (except for the condenser tray) equals the dew point in that mixture pressure, Wilson equation is used for determining K value umns. According to Fig. 2, the former has one inlets (feeds) and two outlets (products). The latter usually includes more than one feed and more than two output flows. According to Fig. 2, the trays of distillation columns are numbered from the top (condenser) to the bottom (reboiler). The feed enters tray “f’ while the bottom and top products exit the column with the flow rates of B and D, respec- tively. To simulate the column, several main parameters including the number of trays (N), reflux ratio (R), top molar over-flow (D), feed plate location (f), column average operational pressure, feed thermal quality and composition and type of condenser must be determined in priori. The feed flow enters the feed tray with liquid fraction q and its specified composition. Based on Figs. 2 and 3, qF of feed enters tray fin the form of liquid and (1-q)F of feed enters tray f-1 in the form of vapor.
    Fig. 4. A block diagram of the design of the distillation column. Fig. 5 shows the algorithm of mentioned process for solving the column's equation as a flow chart.
    Fig. 6. Plot of liquid mole fraction of the existing components for the de-propanizer, current study and [18].
    De-propanizer column specifications.
    Fig. 5. The algorithm of numerical designing the cryogenic distillation column.
    Fig. 7. Plot of components’ liquid mole fraction against the tray number with and without considering the energy equation.
    Fig. 8. Temperature profile of the column in initial design. Table 4
    Fig. 11. Methane liquid mole fraction inside the column for SRK and E-PPR 78 EOSs.
    Fig. 10. Molar liquid fraction profile of methane, ethane, nitrogen and helium.
    Fig. 9. Molar over flow profile in the initial design.
    Fig. 12. Nitrogen liquid mole fraction inside the column for SRK and E-PPR 78 EOSs.
    Fig. 13. Effect of reflux ratio on methane liquid mole fraction at top of the column. Properties of bottom products in the improved state. Table 5
    Fig. 14. Effect of the Reflux ratio on methane liquid mole fraction at the bottom ot column.
    Fig. 15. The variation in the energy consumption of (left) the condenser and (right) the reboiler with the reflux ratio.
    Fig. 16. The mole fraction of methane at the top product for three levels of operational pressure, in terms of feed tray location: (a) R= 13, (b) R= 15 and (c) R=17.
    Fig. 17. Methane mole fraction at the top products for: (a) P=2800kPa, (b) P = 3050 kPa, (c) P=3150 kPa.
    Fig. 20. Liquid mole fraction of methane in top products with different feed plates and total number of trays. P= 3000 kPa and R= 15.
    Fig. 19. Liquid mole fraction of methane in top products with different feed plates and operational pressures. N= 16 and R= 15.
    Fig. 18. Liquid mole fraction of methane in top products with different feed plates and operational pressures. N= 23 and R= 15.
    Fig. 21. Methane concentration in top products for different number of trays. f=4, R= 15, P=3000kPa.
    Mole fraction of terminal products in initial and enhanced condition.
    Fig. 22. Molar fraction of methane and nitrogen, (a) improved state and (b) initial state.
    Fig. 23. Distribution of liquid mole fraction for a number of components, (a) improved state and (b) initial design.
    Table 6
    Table 1
    Density of top and bottom flow of distillation column in the initial design. Table 3
    Feed properties and specifications of initial distillation column design. Table 2
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    THE INFLUENCE OF EXTERNAL FACTORS ON THE DEVELOPMENT OF SEPARATISM IN XINJIANG OF PRC_Mavlonova A.S (in Russian)
    by Vestnik RUDN. International Relations
    The article considers the important geostrategic position of Xinjiang, located at the in-tersection of foci of instability, at least having a common border with Afghanistan and Pakistan. The large-scale military conflict in the Middle... more
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    Space-time resolution of size-dispersed suspensions in Deterministic Lateral Displacement microfluidic devices
    by Maria Anna Murmura and 
    1 more
    Stefano Cerbelli

    2019, The European Physical Journal Special Topics

    Deterministic Lateral Displacement (DLD) is a relatively recent microfluidics-assisted technique which allows the size-based separation of a population of micrometric particles suspended in a buffer solution. The core of the device is a... more
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    Biological and technical study of a partial SHARON reactor at laboratory scale: Effect of hydraulic retention time.
    by Antonio Albuquerque

    2013, Bioprocess and Biosystems Engineering, 36(2), 173-184.

    This study was on the technical and biological characteristics of a partial-SHARON submerged-filter bioreactor of 3 L. The main focus was the influence of the hydraulic retention time (HRT) on biofilms. For this purpose, we used molecular... more
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    Ideal versus real automated twin column recycling chromatography process
    by Fabrice G E Gritti
    Reversed-phase liquid chromatography Planar polycyclic aromatic hydrocarbon isomers Pressure-dependent retention factor Partial molar volume a b s t r a c t The full baseline separation of two compounds (selectivity factors ˛ < 1.03) is... more
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    Expanded bed adsorption for recovery of patatin from crude potato juice
    by Allan Lihme

    1998, Bioseparation

    An expanded bed adsorption process was used to isolate patatin possessing esterase activity, from a crude juice of potato tubers. Patatin is the major storage protein of potato tubers and is released in ample amounts in the processing... more
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    Tuning flexibility to control selectivity in soft porous crystals
    by Nathan Mahynski

    2017

    We use flat-histogram Monte Carlo simulations to study how changing the flexibility of soft porous crystals (SPCs) affects their selective adsorption of a binary, size-asymmetric supercritical fluid. Specifically, we consider mesoporous... more
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    Thermophysical Properties of Acetophenone with N,N-Dimethylethanolamine or with N,N-Diethylethanolamine at Temperatures of (303.15, 313.15 and 323.15) K and Pressure of 0.1 MPa
    by SARAVANAKUMAR KRISHNAN

    2011, Journal of Solution Chemistry

    Densities, viscosities and refractive indices have been determined for mixtures of acetophenone with N,N-dimethylethanolamine or with N,N-diethylethanolamine over the entire composition range at temperatures of (303.15, 313.15 and... more
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    Ni(II) adsorption characteristics of commercial activated carbon from synthetic electroless plating solutions
    by Yennam Rajesh
    Literature data with respect to Ni(II) adsorption from real process streams is scarce. The present work addresses the effect of solution complexity of electroless plating solution on the adsorption efficiency of commercial activated... more
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    iso-Kaurenoic acid from Wedelia paludosa D.C
    by Ronan Batista and 
    1 more
    Arturo San Feliciano

    2010, Anais da Academia Brasileira de Ciências

    A recent reinvestigation of aerial parts of Wedelia paludosa D.C. is described and reports, for the first time, the isolation of iso-kaurenoic acid from this species.
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    Effect of column efficiency on the internal concentration profiles and the performance of a simulated moving-bed unit in the case of a linear isotherm
    by Zouhir Bensetiti

    1997, Journal of Chromatography A

    Simulated moving-bed (SMB) separators have been used successfully to separate or purify continuously two components with different adsorption selectivities. A detailed understanding of their behavior is still lacking, however. A numerical... more
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