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The decontamination of wastewater is an important issue for the nuclear industry. The removal of Sr2+, one of the most problematic radioelements, requires hierarchical materials suitable for fixed-bed processes. This article describes a patented emulsion-templating route for the synthesis of Linde Type A (LTA) zeolite-geopolymer composites with a multiscale porosity. By dispersing zeolite particles in an emulsion oil-in-water containing precursors of geopolymer, LTA zeolite–geopolymer composites can be obtained after curing and eliminating the oil phase. The zeolite particles alter the macroporous structure of the materials (replicating the oil droplets) as well as the size of the mesopores of the geopolymer binder. Moreover, zeolite contents higher than 30 wt% induce a crumbling of the material structure. The presence of LTA zeolite particles increases the selectivity of the composites for Sr2+ in very saline media, while the porous network of the material ensures rapid adsorption. The optimal composite prepared here outperformed a commercial sorbent for the Sr2+ decontamination of a saline wastewater through a packed column. • Geopolymer-zeolite composites were synthesized through an emulsion-templating route. • The zeolite weight percentage in the composite strongly influences its microstructure. • Increasing the amount of zeolite in the material increases its selectivity for Sr2+. • Geopolymer-zeolite composites are well adapted to be used in fixed bed process. [ABSTRACT FROM AUTHOR]

The current study aims to assess the performance and industrial feasibility of using three-phase fluidized bed absorption columns for post-combustion carbon dioxide (CO 2) capture. The analysis is based on a mathematical model of a scaled-up fluidized bed absorption column that has been validated using pilot plant experimental data. The focus is on evaluating the energy efficiency of the fluidized bed column in comparison to packed bed technologies, which are currently widely used. The results of the analysis are evaluated in terms of three performance indicators (i.e., absorption efficiency, carbon capture rate, and energy performance index) and compared to packed bed columns. Simulation results indicate that the best column configuration is represented by a three-stage absorber and that the system performs optimally when particle diameter and density decrease with each section. Consequently, this leads to an increase in the total fluidized bed height and carbon capture rate by up to 25%. The energy performance index is maintained below 3.6, indicating an energy-efficient operation of the system. As such, the findings of this study suggest that the use of gas-solid-liquid three-phase fluidized bed absorption columns for post-combustion CO 2 capture is a promising technology for the implementation of CCUS and for achieving of climate neutrality targets. [Display omitted] • Mathematical modeling through experimental assessment. • Consideration of a three phase, gas-solid-liquid, fluidized bed absorber for carbon capture. • Integration of gas-solid-liquid fluidized bed absorber in a full-scale carbon capture plant. • Performance analysis of three phase absorption in terms of energy and carbon capture efficiency. • Comparison of the obtained performance with the one obtained using regular packed bed absorbers. [ABSTRACT FROM AUTHOR]

This research describes a hybrid solar desalination system that includes a humidification-dehumidification unit as well as a solar still unit. The current system is being studied numerically. A one-dimensional model of the important heat and mass exchanges, as well as the flow field, was built using the finite difference method. Freshwater productivity is calculated under various operating and weather conditions. The model has been modified to investigate the steady-state behavior of the system components. Four major parameters that have a significant impact on system water production are investigated: the feed flow rate of cooling water through the dehumidifier unit, the airflow rate, and the number and height of packing columns. According to the results, the proposed hybrid desalination system provides appropriate operational compatibility between HDH technology and solar energy. The system can provide a daily production of up to 35 liters per day. Increasing the number of packing columns results in a higher increase in fresh water productivity than increasing the height of the packing columns. The optimal air flow rate at a constant saline-water flow rate is obtained. For high airflow rates, the packing column height doesn't significantly affect the daily water production. System performance is investigated by four main parameters: gained output ratio (GOR), humidifier efficiency, exergy efficiency, and system efficiency. The system efficiency reached about 65% and the GOR reached 3.1. The humidifier's efficiency varied between 50% and 75%. The maximum exergy efficiency reached about 5.2%. [ABSTRACT FROM AUTHOR]

• Hydrodynamics in cooling tower packing has been numerically simulated. • Main local and system scale hydrodynamic parameters have been obtained. • Packing wetting rate and film thickness increase with water flow inlet increase. • A correlation has been proposed for interfacial area to evaluate transfer phenomena. Wet cooling towers are used in many industrial processes but hydrodynamic behaviour of air-water counter flows in towers packing remains unknown. Hydrodynamics is directly linked with main operating issues (e.g. packing fouling reducing cooling efficiency). The objective of this work is to use Computational Fluid Dynamics (CFD) simulations to characterize local hydrodynamic parameters such as water film thickness, velocity or wall shear stress and system scale parameters such as wetting rate or interfacial area. After a theoretical study of fluid mechanics, Volume of Fluid (VOF) simulations, with dedicated models for air/water interface capture and solid/liquid contact angle, successfully reproduced water falling films on packing surface. Simulations allowed the calculation of main water flow local and system parameters. The results have pointed out trends of increasing liquid film thicknesses and wetting rates with increasing water flowrate in agreement with experimental observations. A correlation of the interfacial area has been proposed as a function of the hydrodynamic adimensional numbers to characterize transfer phenomena in the considered packing. [ABSTRACT FROM AUTHOR]

Liquid distributor is an important internal in packed distillation columns. One of the key features of this equipment is the drip point density, which corresponds to the number of irrigation points per area of the cross-section. For gravity liquid distributors, increasing the number of irrigation holes generally requires small hole diameters, which makes the equipment more sensitive to plugging. In this work, we disclose a new gravity liquid distributor that achieves large drip point densities without requiring smaller irrigation holes. This distributor is an adaptation of the classic orifice-pan type, in which we add a tree-like structure made of wires to spread the liquid dripping from the orifices. The liquid flows outside the wires and splits several times over the different branching levels before falling on the packed bed. From an orifice-pan configuration with drip point density of 736 pts/m2, we designed and constructed enhanced distributors with a theoretical irrigation density of 14,800 pts/m2. Performance comparison using a recently disclosed structured packing shows that these enhanced distributors can decrease HETP from 0.45 m to 0.27 m. • We design a gravity liquid distributor for separation columns. • It is based on a tree-like structure increasing the drip point density. • Liquid flows outside the wires. • HETP is decreased from 0.45 m to 0.27 m for a recent packing. [ABSTRACT FROM AUTHOR]

The study investigates the phenomenon of axial dispersion in a packed absorption column, which is known to reduce the efficiency of separation equipment by reducing the mass transfer driving force. The aim of the study is to determine the Bodenstein number, which represents axial dispersion, for five types of modern packings used in the column. The packings used in the study were random packings (NeXRing0.7 and NeXRing1.2) and structured packings (MellaPak350Y, 452Y, and 500Y). The data obtained from dynamic experiments in the form of a response to a step change in tracer substance concentration were compared to a diffusion-type differential equation, which was solved with boundary conditions for a closed system. By measuring the responses at two different packed bed heights and using convolution, the influence of the end effects was eliminated. The lowest axial dispersion was obtained for M452Y, and it is almost twice as low as for M250Y. It was found that the values of the Bodenstein number for standard series of Mellapak type packing (M250Y, M350Y and M500Y) have comparable axial dispersion, especially at low liquid rates. The axial dispersion obtained for random packings is generally higher compared to structured packings. However, compared to other random packings such as Pall rings (25 mm) and Intalox saddles (25 mm), NXR0.7 and NXR1.2 exhibit up to a two-fold reduction in axial dispersion. • Axial dispersion and liquid holdup on five types of modern packings have been determined. • Axial dispersion is comparable for structured packings M250Y, M350Y and M500Y. • The values of Bodenstein number for M452Y are higher by 50 % than for M350Y. • The values of Bo L for NXR0.7 and NXR1.2 are up to twice as high in comparison with random packings from previous generations. [ABSTRACT FROM AUTHOR]

The distillation of three binary test systems differing in the surface tension gradient along the column, namely: cyclohexane/n-heptane (negative), cyclohexane/toluene (neutral), n-hexane/cyclohexane (positive), has been performed under total reflux in the i.d. 0.3 m distillation column packed with MellapakPlus 452. Y structured packing. Although all constituents are C 6 – C 7 hydrocarbons with close physical properties in the gas phase, the resulting HETP differ by up to 20 %. Further analysis suggests that system negativity causes the approx. 30 % decrease of the effective interfacial area with respect to positive and neutral systems, which behave comparably. Indeed, observation of the distillation on the inclined plate in the IR spectra shows breakage of the negative system liquid films into rivulets, supporting the result. [Display omitted] • HETP, kGa of MellapakPlus 452. Y measured in 0.3 m distillation column. • Significant difference between HETP of negative and neutral/positive systems. • Distillation effective interfacial area evaluated using kG chemisorption correlation. • Liquid film of the negative system breaks into rivulets as conveniently observed in IR spectra. [ABSTRACT FROM AUTHOR]

Predictive correlations for packed distillation and absorption columns usually cannot account for changes in operating limits due to phenomena such as fouling. A method for detection of loading and flooding points even under altered operating conditions would therefore be highly desirable. In this work, a new approach for real-time detection of packed column loading and flooding points is introduced. The method utilises Fourier analysis of pressure drop data. Pressure drop fluctuations occurring even under steady-state conditions are sampled and treated with Fast Fourier transform (FFT) to derive the corresponding frequency spectra. Results of examinations with three structured packings (RSP 250Y, RMP N 250X, RMP N 250Y) conducted at three liquid loads each show that operating regions (below loading point, loading point, loading region, flooding point) can be identified from the obtained frequency spectra. Starting at the loading point, certain amplitudes within the spectra grow and increase up to the flooding point. This behavior is consistent for all examined packings. The results from this study suggest that the proposed approach could support column operation as an additional monitoring tool that is low in cost and not reliant on additional measurements besides pressure drop. [Display omitted] • A Real-time detection of packed column loading and flooding points is introduced. • Identification of operating regions is done with Fourier analysis of pressure drop data. • Results for three liquid loads of three structured packings (RSP 250Y, RMP N 250X, RMP N 250Y) are presented. • Starting at the loading point, frequency spectra show growing amplitudes. [ABSTRACT FROM AUTHOR]

CHase catalyzes chlorogenic acid (CGA) hydrolysis to yield equimolar quinic (QA) and caffeic (CA) acids, products of high value and keen industrial interest. We proposed the preparation and characterization of the nonviable mycelium of Aspergillus niger AKU 3302 containing a cell-associated CHase (CHase biocatalyst) for application in hydrolyzing the CGA from yerba mate residues to produce QA and CA. When the vegetative mycelium was heated at 55 °C for 30 min, no loss of CHase activity occurred, but vegetative mycelial growth and spore germination ended. The CHase biocatalyst did not limit mass transfer above 100 strokes min−1. The reaction rate increased with catalyst loading and was kinetically controlled. The CHase biocatalyst exhibited suitable biochemical properties (optimum pH 6.5 at 50 °C) and high thermal stability (remaining stable at up to 50 °C for 8 h). The cations in yerba mate extracts did not affect CHase activity. We observed no apparent loss in the activity of the CHase biocatalyst after even 11 batch cycles of continuous use. The biocatalyst retained 85% of its initial activity after 25 days of storage at pH 6.5 and 5 °C. When a yerba mate extract was passed through a glass column packed with the biocatalyst, an effective bioconversion of CGA into CA and QA occurred. CHase activity produced a natural biocatalysis with considerable operational and storage stability; which capability, being a novel biotechnological process, can be used in the bioconversion of CGA from yerba mate residues into CA and QA at a substantially reduced cost. [ABSTRACT FROM AUTHOR]

Dietary restriction of phenylalanine is the predominant treatment for phenylketonuria. However, the currently available medicated formulations depend on an arduous and unsustainable chemical extraction procedure, which inflates the product's price. Here, we describe a method that uses immobilized phenylalanine ammonia lyase (PAL) and offers a sustainable solution to generate a low-phenylalanine protein supplement for phenylketonuria patients. This enzyme deaminates phenylalanine to trans-cinnamic acid. Here, we optimized the high cell density cultivation of a recombinant Escherichia coli strain harboring Anabaena variabilis PAL (AvPAL) and achieved protein titers greater than 400 mg/l. This AvPAL protein was immobilized on multiwall carbon nanotubes, and the bioconjugate retained > 50 % activity after ten successive cycles with significantly improved thermostability. Batch deamination with the bioconjugate showed an 80 % reduction in the total phenylalanine content of soya protein hydrolysate. In a continuous packed bed column, > 98 % of the phenylalanine content was depleted at a feed flow rate of 0.1 ml/min, resulting in a space-time yield of cinnamate of 6.65 g/l/h. In a 72-h continuous run, the bioconjugate lost only 2 % of its activity with an operational inactivation constant of 3.9 × 10−5 min−1. This simple covalent immobilization method offers the potential to generate low-phenylalanine diet for phenylketonuria patients. [Display omitted] • Low phenylalanine (Phe) formulation is the mainstay treatment for Phenylketonuria. • Immobilized AvPAL enzyme offers sustainable solution for protein pretreatment. • Pretreatment with CNT-AvPAL showed >98 % reduction in Phe content of protein. • hydrolysate [ABSTRACT FROM AUTHOR]

• PBDEs and PAHs often co-exist at e-waste recycling sites. • Considerable amounts of BDE-209 and phenanthrene are leached from surface soil. • Leaching potential of BDE-209 is closely related to the release of mineral particles. • Leaching potential of phenanthrene correlates with dissolved organic carbon. Polybrominated biphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs) are commonly detected contaminants at e-waste recycling sites. Against the conventional wisdom that PBDEs and PAHs are highly immobile and persist primarily in shallow surface soils, increasing evidence shows that these compounds can leach into the groundwater. Herein, we compare the leachabilities of PBDEs vs. PAHs from contaminated soils collected at an e-waste recycling site in Tianjin, China. Considerable amounts of BDE-209 (0.3–2 ng/L) and phenanthrene (42–106 ng/L), the most abundant PBDE and PAH at the site, are detected in the effluents of columns packed with contaminated soils, with the specific concentrations varying with hydrodynamic and solution chemistry conditions. Interestingly, the leaching potential of BDE-209 appears to be closely related to the release of colloidal mineral particles, whereas the leachability of phenanthrene correlates well with the concentration of dissolved organic carbon in the effluent, but showing essentially no correlation with the concentration of mineral particles. The surprisingly different trends of the leachability observed between BDE-209 and phenanthrene is counterintuitive, as PBDEs and PAHs often co-exist at e-waste recycling sites (particularly at the sites wherein incineration is being practiced) and share many similarities in terms of physicochemical properties. One possible explanation is that due to its extremely low solubility, BDE-209 predominantly exists in free-phase (i.e., as solid (nano)particles), whereas the more soluble phenanthrene is mainly sorbed to soil organic matter. Findings in this study underscore the need to better understand the mobility of highly hydrophobic organic contaminants at contaminated sites for improved risk management. [Display omitted] [ABSTRACT FROM AUTHOR]

The experimental distillation apparatus presented here serves to simulate the hydrodynamic and mass transfer conditions in a distillation column packed with the structured packing. It produces a film of the boiling liquid mixture flowing down the inclined plate with counter-currently flowing vapour of that mixture under total reflux with the mass transfer proceeding between the phases. The inclined plate instead of the sheet of structured packing is used for its simplicity as the first approximation in this work. The apparatus enables observation of the liquid film by means of a thermal imaging camera through a heated KBr window. Thermograms of films of IR-translucent mixtures (such as the cyclohexane/n-heptane mixture) provide information on the spatial distribution of the film thickness, while those of films of IR-opaque mixtures (such as methanol/propanol mixture) should reveal the spatial distribution of the mass transfer intensity across the interface. So far the results remain qualitative. Monitoring of the IR-opaque liquid surface is complicated by the relatively well-visible vapour phase in the IR spectrum, which unpredictably and irregularly hinders the view. • Observation of the distillation process in the IR. • Qualitatively different information from termograms of the IR-translucent and IR-opaque liquid films. • Measurement of the IR absorption coefficients of the distillation mixtures constituents in the liquid and vapour phases. [ABSTRACT FROM AUTHOR]

Foam formation in distillation columns leads to various negative effects such as reduced distillation throughput and reduced separation performance. In order to determine the influence of foam on distillation throughput and separation performance, measurements with chlorobenzene/ethylbenzene (CB/EB) and water/monoethyleneglycol (water/MEG) mixtures in a DN50 laboratory distillation setup were carried out. As internals, structured packings were compared to randomized packings with different materials. Results show that structured packings were more susceptible to foam and had greater losses in separation performance under the influence of foam as compared to randomized packings. However, in absolute terms, foam-loaded structured packings showed the highest separation efficiencies compared to randomized packings. An increase in column wall temperature above adiabatic conditions resulted in an increased foam loading and a decreased separation performance. Pressure drops were similar between packings, but foam loaded randomized packings showed a slightly lower pressure drop. [Display omitted] • Investigation of evaporation-induced foam in randomized and structured packings. • Randomized packing was found to destabilize foam to a greater extent. • Foam decreases the separation efficiency of randomized and structured packings. • Quantification of the reduction in distillation throughput due to foam in packed columns. • Increased column wall temperatures affect foam formation and separation performance. [ABSTRACT FROM AUTHOR]

In recent decades, supercritical fluid has gained increasing interest in various industries. One of its promising applications is the extraction of valuable compounds from solid materials such as various plant parts, known as supercritical fluid extraction (SFE). With growing interest to employ SFE commercially, it is vital to provide reliable and robust mathematical modeling for the SFE to optimize the process and achieve maximum extraction yield and to better understand the process mechanism. The present review aims to critically report and discuss different strategies proposed thus far for the mathematical modeling of the SFE process in packed bed columns. The main features, key assumptions and their validity, mathematical expressions, and applications of each modeling strategy are evaluated. Additionally, this manuscript covers a comprehensive review of the different studies carried out for SFE of plant matrices encompassing mathematical modeling part. The studied systems in each research (both solute and solid substrate) along with the employed models as well as the ranges of the operational conditions such as pressure, temperature, and solvent flow rate are also highlighted. This review assists the scientific community to identify the most suitable models and the appropriate operating conditions for different systems in the SFE process. • Different existing SFE modelling approaches including the latest ones are reported and critically reviewed. • Model applications, and their validity are highlighted. • Recommendations for future research and industrial scale-up are put forward. [ABSTRACT FROM AUTHOR]

Structured packings in distillation columns present an opportunity for process optimization. Therefore, current design processes for columns with structured packings are evaluated with respect to their industrial applicability, and a power law equation is proposed for transferring HETP values of a reference system to a test system. A design process that includes CFD simulations is presented, and the CFD simulation setup is introduced. The validity of the simulation setup is examined with regard to the following mixtures: nitrogen/oxygen, chlorobenzene/ethylbenzene, and cyclohexane/n-heptane. Diffusion coefficients are varied in the simulation, and their influence on the HETP value is evaluated. The simulated HETP values are then compared with established mass transfer models and demonstrate a high level of agreement. [Display omitted] • Equilibrium stage and transfer unit concepts for packed column design are compared. • A novel HETP scaling equation for improved packed column design is proposed. • GCST model is successfully used for two-phase CFD simulation in structured packing. • Distillation reference mixtures are found to be suitable for the simulation setup. • Separation efficiencies from simulation are comparable to mass transfer models. [ABSTRACT FROM AUTHOR]

The study and characterization of random and structured packed columns has been of primary importance to develop reliable model for engineer design tool. Those models, often developed after long experimental campaign, usually lack the understanding of the local scale phenomena such as flooding and blockage that is necessary in order to design more efficient packing geometries. The present study objective is to be able to understand the parameters influencing the incipience of the blockage phenomenon that is observed at any regime. The study make use of a numerical approach based on the Volume-of-Fluid (VOF) multiphase method. The method is employed to observe the free surface in various flow conditions for different elementary geometries. For the condition studied, the results show the corrugation geometry and material to be the main actors in the blockage incipience. The study also highlights the design features that are critical in the design of packed bed geometries to ensure a satisfactory specific coverage as well as good flow periodicity to develop accurate design tools. • Study of the incipience of the blockage phenomenon for three elementary geometry with the consideration of column and droplet flow. • Geometry and contact angle are shown to be the main contributor to the blockage incipience. • Accurate simulations at the local scale are key to improve corrugations geometries to enhance heat and mass transfer performances while reducing.expenditure. [ABSTRACT FROM AUTHOR]

• The new sorbent materials derived from the β 2 -AR immobilized microspheres. • A simple method for sample pretreatment using protein affinity-selection spin column under the operational centrifugation. • Target-specific affinity separation of the bioactive compounds from herbal extract. Excellent pretreatments before instrumental analysis are critical for separation and determination of target compounds for discovery of new drugs from herb medicines. We developed a rapid and highly-selective method to separate the bioactive compounds from herbal extract using protein affinity-selection spin column, which was packed with the new sorbent materials from integrating the recombinant β 2 -adrenoceptor (β 2 -AR) directly out of cell lysates onto the surface of microspheres. Protein affinity-selection spin column was placed in a centrifugal tube, where after the non-specific binders were released to the filtrate under the operational centrifugation, the specific binders on the spin column were cleaned with a washing solvent for LC-MS analysis. The known agonists of β 2 -AR were retained/released on protein affinity-selection spin column but not on control column, demonstrating the method with good recovery (79.4∼95.7 %) and high repeatability (RSD < 3.5 %). The adsorption features of three ligands on the spin column were described best by Prism saturation binding model, and the high-affinity binding and the large binding capacity of the spin column make it feasible to trap the trace analytes effectively. It was applied in separating bioactive compounds from Alstoniae Scholaris extract, two of which were identified as picrinine and oleanolic acid in combination with LC-MS and verified as the potential agonists towards β 2 -AR though molecular docking and cell experiments. Our study demonstrated that, the spin column with the immobilized protein sorbents in the centrifugal filter device represents a promising tool, enabling rapid and target-specific affinity separation of the bioactive compounds from herbal extract. [ABSTRACT FROM AUTHOR]

• Continuous production of HMF from fructose in μPBRs with solid acid catalyst. • Liquid-liquid two phase RTD in μPBRs is obtained. • It takes only 26.3 s to obtain 90.2 % HMF yield. • k L a is 1–3 orders of magnitude larger than conventional reactors. • The kinetic model is established and product yields are predicted. The efficient synthesis of the platform chemical 5-hydroxymethylfurfural (HMF) is of great significance for the production of downstream value-added bio-based chemicals. Herein, the highly-efficient and continuous synthesis of HMF is demonstrated in micropacked bed reactors (μPBRs) with HND-580. 95.3 % fructose conversion, 90.2 % HMF yield, and 99.3 % HMF extraction efficiency can be achieved within 26.3 s in μPBRs. The space–time yield (STY) of μPBRs is more than two times of magnitude greater than conventional fixed bed reactors (FBRs) and stirred tank reactors (STRs). The organic phase liquid holdup of liquid–liquid system is obtained at the range of 0.82–0.90, which is measured for the first time in μPBRs. The liquid–liquid mass transfer coefficient of μPBRs is 1.68 × 10-2 to 1.68 × 10-1 s−1, which is 1–3 orders of magnitude larger than STRs and packed columns. In addition, a heterogeneous kinetic model for the synthesis of HMF in water-MIBK biphasic system is established in μPBRs. The fructose conversion and HMF yield were predicted and the error was within ± 20 %. [ABSTRACT FROM AUTHOR]

[Display omitted] • Accelerating terephthalic acid formation is achieved in a hydrothermal semi-batch setup. • TPA is the main component mobilized in the flow-through water, oligomer products can be withheld in the hydrothermal system. • Approximative reactor signal deconvolution shows that the reaction is not solubility limited. This research delves into the hydrothermal decomposition of PET [poly(ethylene terephthalate)] between 523 and 573 K temperature at 10 MPa pressure. PET was placed in a packed column, and a constant water flow was maintained with an average residence time of water between 403 and 430 s as it travelled from the reactor to the end of the system. Terephthalic acid (TPA) recovery ranged from 87 % to 94 %, increasing with the temperature. The time of full conversion of the 0.5 g PET by 1 g/min water flow rate reduced from 2500 to 1200 sec, with increasing temperature. To prevent premature precipitation of TPA during cooling, an alkaline quench stream was employed. Terephthalic acid isolation involved acidification-driven precipitation and subsequent filtration at atmospheric pressure. The solid dry TPA product underwent NMR analysis, showing structural conformity and DSC/TGA measurement, which presented a purity of 99.5 w/w%. The fractional end-of-pipe sampling showed accelerating reaction rates at each temperature, which supports the autocatalytic nature of hydrothermal disintegration of the PET. Using the determined residence time distribution in the system, from the end-of-pipe data a crude Fourier transform-based backward calculation was carried out to map the variation of the TPA concentration in the high-temperature and −pressure reactor. [ABSTRACT FROM AUTHOR]

Liquid-film-based liquid-liquid extraction enhances mass transfer compared to droplet-based extraction (Chang et al., Ind Eng Chem Res, 62 (2023), 17297-17305). This new technique forms discrete liquid films by directing the dispersed phase flowing along a single wire immersed in the continuous phase. To showcase its scalability, this communication paper introduces a multi-wire column for lithium recovery from salt lake brines using a mixed extractant as an organic phase. Housing up to 19 vertically oriented wires, the column demonstrates excellent scalability and outperforms conventional packed and spray columns. These characteristics make it a promising candidate for efficient industrial-scale lithium extraction. [Display omitted] • A multi-wire column is proposed to recover lithium from salt lake brines. • The column demonstrates excellent scalability with increasing wire number. • A 19-wire column is tested under different continuous/dispersed-phase flow rates. • The 19-wire column outperforms conventional spray and packed columns. [ABSTRACT FROM AUTHOR]

Gas–liquid membrane contactors are a promising alternative to packed columns that suffer from channeling, bubble formation, and flooding problems. In this study, potassium serinate + piperazine (PSZ) and potassium alaninate + piperazine (PAZ), which are amino acid salts with good CO 2 absorption performances and high surface tensions, are investigated to determine the effects of the operating parameters on the CO 2 removal efficiency, CO 2 absorption flux, CO 2 loading, and overall mass-transfer coefficient in the membrane contactor process. The experimental results demonstrate that the 2.5 M PSZ and 2.5 M PAZ absorbents outperform 2.5 M monoethanolamine (MEA) under various operating conditions, including the gas flow rate, liquid flow rate, CO 2 concentration, and CO 2 -loaded absorbent. Based on these results, an expression for predicting the CO 2 loading from the pH is proposed. The amount of cross-over confirmed that amino acids with high surface tension have better resistance to membrane wetting than 2.5 M MEA. In addition, empirical correlation expressions were established from the results of several operating parameters. The absolute average deviation (AAD) values were 6.50 %, 2.95 %, and 4.71 % for 2.5 M MEA, 2.5 M PSZ, and 2.5 M PAZ, respectively, suggesting good agreement between the theoretical and experimental results. [Display omitted] • Amino acid salt-based absorbents were applied in a membrane contactor. • Various operating parameters were examined during the membrane contactor process. • Cross-over was measured to explain membrane wetting. • Expression for predicting CO 2 loading from pH is proposed. • Empirical correlation equation for CO 2 removal efficiency is established. [ABSTRACT FROM AUTHOR]

This study focused on the treatment of a multi-metal waste sourced from laboratory settings, containing the mixture of Cr3+, Mn2+, Co2+, Fe3+, Ni2+, Cu2+, Zn2+, Sr2+, Hg2+, and Pb2+, at pH 1.0. The combination of flocculation with a polycation and subsequent precipitation with NH 4 OH removed Cr3+, Mn2+, Co2+, Fe3+, Zn2+, Hg2+, and Pb2+ as solid particles. These particles were separated from the supernatant and incorporated into cementitious pastes, thereby mitigating the leaching of hazardous ions into water. Ni2+, Cu2+, Sr2+ ions remained as soluble complexes in the supernatant that passed through fix-bed columns packed with cryogels composed of carboxymethyl cellulose (CMC) or chitosan (CHI), both reinforced with sugarcane bagasse (BG) microparticles. Among these cryogels, the composition featuring a mass ratio of 1:1 between CMC and BG (CMCBG50) exhibited superior efficacy in metal removal, particularly in adsorbing Cu2+ ions, a metal of significant economic interest. Breakthrough curves for the adsorption of Cu2+ on CMCBG50 indicated that the highest adsorption capacity of ∼ 44 mg/g was achieved at flow rate of 1 mL/min and 0.2 g of adsorbent. FTIR-ATR, SEM-EDS and X-ray fluorescence analyses allowed proposing an adsorption mechanism based on metal-OH chelation and metal-carboxylate interactions. The spent CMCBG50 adsorbents were pyrolyzed employing a CO 2 laser. This preliminary study indicated a substantial reduction in the electrical resistance of the pyrolyzed material, approximately fivefold compared to the pristine material. This outcome indicates a promising path to meet the principles of the circular economy practices, wherein waste can be sustainably reused. [Display omitted] • Flocculated and precipitated metal ions were safely immobilized into cement pastes. • Ni2+, Cu2+, and Sr2+ ions were efficiently adsorbed on cellulose-based cryogels. • Combined sugarcane bagasse and carboxymethyl cellulose led to the most efficient adsorbents. • Metal ion-OH chelation and metal ion-carboxylate interactions drove the adsorption process. [ABSTRACT FROM AUTHOR]

The high electronegativity and solubility of fluoride ions (F-) in water at low concentrations pose challenges for their treatment and recovery. To effectively adsorb F-, cellulose beads with trapped CeO 2 nanoparticles (CeO 2 @CBs) were fabricated from a NaOH/urea aqueous solution by the optimal extrusion dropping technology. The CeO 2 @CBs exhibited a maximum removal efficiency of 99.15 % for 10.0 mg L−1 F- at 45°C, pH=3.0 and an adsorbent dose of 1.0 g. The CeO 2 @CBs were characterized using SEM-EDS, FT-IR, XRD, and XPS. These findings demonstrate that CeO 2 nanoparticles were uniformly entrapped in cellulose beads and reveal that the removal mechanism involves anionic exchange and electrostatic attractions between protonated hydroxyl on CeO 2 @CBs surface and F-. The results show that the anion competition sequence that affects the F- adsorption efficiency was Cl−−2−3−. CeO 2 @CBs were directly packed into columns, exhibiting exceptional adsorption efficacy and remarkable stability in column experiments. Even after three desorption cycles, the adsorption performance remained above 95 %. Because the designed CeO 2 @CBs have a simple preparation process, high adsorption efficiency and environmental friendliness, they can provide valuable insights for designing new adsorbents and removing F- from aqueous solutions. • At 45°C, pH=3.0 and 10.0 mg L−1 F- solution, the adsorption efficiency was 99.15 %. • An optimal extrusion dropping technology in NaOH/urea aqueous solution was used to prepare CeO 2 @CBs. • The removal mechanism involved electrostatic attraction and ion exchange. • CeO 2 @CBs had excellent column adsorption performance. • CeO 2 @CBs remained above 95 % excellent adsorption performance after desorption cycles. [ABSTRACT FROM AUTHOR]

• Systematic HILIC assay development of polar analytes remains a challenge. • A new, automated HILIC-DAD-CAD method development workflow for polar analytes. • Screening of 12 columns with sub-2.7 µm fully and superficially porous particles. • Evaluation of different eluent pH and column equilibration time. • Diverse compounds and real-life common pharmaceutical examples were explored. The pharmaceutical industry is rapidly advancing toward new drug modalities, necessitating the development of advanced analytical strategies for effective, meaningful, and reliable assays. Hydrophilic Interaction Chromatography (HILIC) is a powerful technique for the analysis of polar analytes. Despite being a well-established technique, HILIC method development can be laborious owing to the multiple factors that affect the separation mechanism, such as the selection of stationary phase chemistry, mobile phase eluents, and optimization of column equilibration time. Herein, we introduce a new automated multicolumn and multi-eluent screening workflow that streamlines the development of new HILIC assays, circumventing the existing tedious 'hit-or-miss' approach. A total of 12 complementary columns packed with sub-2 µm fully porous and 2.7 µm superficially porous particles operated on readily available ultra-high pressure liquid chromatography (UHPLC) instrumentation across a diverse set of commercially available polar stationary phases were investigated. Different mobile phases with pH ranging from pH 3 to 9 were evaluated using different organic modifiers. The gradient and column re-equilibration were judiciously set to ensure a reliable assay screening framework that indicates promising conditions for subsequent method optimization to achieve resolution of challenging mixtures. This UHPLC screening system is coupled with a diode array and charged aerosol detectors (DAD, CAD and mass spectrometry) to ensure versatile detection for a variety of compounds. This fast-screening platform lays the foundation for a convenient generic workflow, accelerating the pace of HILIC method development and transfer across both academic and industrial sectors. [ABSTRACT FROM AUTHOR]

The role of the average pore diameter (APD) of 1. 7 μ m Atlantis T M Premier BEH T M Particles derivatized with a zwitterionic group (propylsulfobetaine) on the efficiency of their 2.1 × 50 mm hydrophilic interaction liquid chromatography (HILIC) packed columns is investigated experimentally. Van Deemter plots for toluene (neutral, hydrophobic), cytosine (neutral, polar), tosylate (negatively charged), bretylium and atenolol (positively charged) were measured on three HILIC columns packed with BEH Z-HILIC Particles having APDs of 95 Å, 130 Å, and 300 Å. The intraparticle diffusivities of the analytes across these three BEH Z-HILIC Particles were measured by the peak parking method. The experimental data reveal that the slope of the C-branch of the van Deemter plots can be reduced by factors of about 15 for toluene, 2.5 for cytosine, 6 for atenolol, 5 for tosylate, and 14 for bretylium with increasing the APD from 95 Å to 300 Å. This observation is explained by: (1) the reduced amount of the highly viscous water diffuse layer and subsequent increase of the amount of acetonitrile-rich eluent in the mesopores, (2) the localized electrostatic adsorption of the retained analytes onto the zwitterion-bonded BEH Particles, and (3) depletion/excess of the analytes into the water diffuse layer. A general model of intraparticle diffusivity was then proposed to account for the impact of the APD of Z-HILIC Particles on the solid-to-liquid mass transfer resistance of small molecules. The model highlights the relevance of the thickness of the water diffuse layer, the access of the bulk eluent into the mesopore, the localized electrostatic adsorption, and the partitioning constant of the retained analyte between the bulk eluent and the water diffuse layer. • Mass transfer of BEH Z-HILIC columns of different pore sizes are studied. • The van Deemter C coefficient decreases with increasing mesopore size. • Particle absorption rate and intra-particle diffusivity are affected by mesopore size. • Z-HILIC intra-particle diffusivity model is proposed to explain this pore size effect. [ABSTRACT FROM AUTHOR]

• An efficient method for the isolation of radium from thorium was reported. • Separation behaviors in batch and column modes were systematically investigated. • Hot test demonstrated that 228Ra and 224Ra was easily separated from 232Th. • Separation mechanism was illustrated successfully by the species distribution. In recent years, targeted-α-nuclide therapy (TAT) has been widely concerned in the world. As one of the few representative TAT nuclides, 212Pb showed good efficacy in cancer treatment; however, the amount remains scarce. Separating 228Ra and 224Ra from 232Th is expected to fundamentally solve this issue, since they both are the parent nuclides of 212Pb and can be used in generators. In this work, an efficient method for trace radium isolation from bulk thorium was proposed and verified through a systematic investigation of the adsorption behaviors of an anion exchanger denoted IRA900 toward thorium and barium/radium. Batch experiments suggested that IRA900 had unique selectivity for thorium in nitric acid solution, with almost no barium adsorbed. The thorium adsorption performance kept improving with increasing concentration of nitric acid and decreasing temperature. The adsorption kinetics and adsorption isotherm could be well fitted by the pseudo-second-order kinetic model and the Langmuir model, respectively. Column experiments suggested that thorium could be effectively immobilized by a column packed with IRA900, while barium was directly penetrated. For desorbing the fixed thorium, 0.1 M HNO 3 was optimal. A final hot test demonstrated the successful radium isolation from bulk thorium, with high chemical yield and purity. The selective separation mechanism was attributed to the formation of an anionic [Th(NO 3) 5 ]− complex, while barium or radium existed in the cationic form in any nitric acid concentration. This work provides a promising method for separating trace radium from thorium, which will be significant for promoting the large-scale utilization of 212Pb. [ABSTRACT FROM AUTHOR]

In this study, we introduce a novel multi-scale Pore Network Model (PNM) designed to couple reactor-scale and particle-scale transport phenomena. To model reactor-scale phenomena, we employ a 3D reactor-scale PNM. This reactor-scale PNM is extracted from a packed column filled with spherical particles. Through analysis of the reactor-scale PNM, we obtain insight into the flow behavior of the reactor, which, in turn, is utilized for modeling species dispersion. For modeling particle-scale transport phenomena, we employ a 3D particle-scale PNM to simulate species diffusion and reaction within a spherical porous catalyst particle. This particle is represented with thousands of micro-spheres to represent the porous catalyst particles. The developed particle-scale PNM allows the treatment of realistic 3D boundary conditions on the catalyst particle's surface. This paper presents an innovative methodology by combining the reactor-scale PNM with the particle-scale PNM, achieved through the incorporation of surface fragments. Both the reactor-scale and particle-scale PNMs have undergone thorough calibration and validation in our previous research (Fathiganjehlou et al. 2023; 2024). The developed multi-scale PNM offers a fast model capable of generating local partially resolved results for the catalytic packed bed reactor within a matter of minutes. This model lays the foundation for multi-scale pore network modeling of real packed bed reactors. [Display omitted] • Introduction of a multi-scale PNM for modeling of a reactive packed bed. • Realistic 3D reactor-scale and particle-scale PNMs for accurate simulations. • Innovative integration of reactor and particle-scale PNMs using surface fragments. • Efficient modeling of dispersion, diffusion, and reaction in a packed bed reactor. • Thorough calibration and validation of multi-scale PNM. [ABSTRACT FROM AUTHOR]

• SMA copolymer brush-based HPLC stationary phases were exploited and developed. • Sil-SMA-DGME and Sil-SMA-EHOE chromatographic columns were successfully fabricated. • They were successfully used for identification of lipids from human lung cancer cells. Styrene-maleic acid (SMA) copolymer has received much attention for its excellent solubilization characteristics. In this work, SMA copolymer brush-based chromatographic stationary phases were exploited and developed for the first time. First, SMA copolymer brush was in situ grown on the surface of spherical silica via living/controlled reversible addition-fragmentation chain transfer (RAFT) polymerization method. Subsequently, as a proof-of-concept demonstration, the copolymer was esterified by diethylene glycol mono-2-ethylhexyl ether (DGME) and 2-(2-ethylhexyloxy) ethanol (EHOE), respectively. The obtained Sil-SMA-DGME and Sil-SMA-EHOE copolymer-brush chromatographic stationary phases were characterized by transmission electron microscopy, Fourier transform infrared spectrometer, X-ray photoelectron spectroscopy, and thermogravimetric analysis, respectively. The chromatographic retention mechanism indicated that both the two packed columns exhibited hydrophilic/reverse mixed-mode retention modes. The maximum column efficiency was up to 71,000 N/m. The chromatographic separation performance evaluation indicated that the novel kind of stationary phases had excellent separation capabilities for hydrophilic, hydrophobic compounds and phospholipid standards. In addition, by combination with mass spectrometry identification, the Sil-SMA-DGME column was further exploited for separation and identification of phospholipids in human lung cancer cells. Totally, 9 classes including 186 phospholipid species were successfully identified. The results demonstrated the promising application prospects of the novel kind of SMA copolymer-brush chromatographic stationary phases. [ABSTRACT FROM AUTHOR]

[Display omitted] • An improved fully automated HPLC-SARA fractionation has been developed and optimized. • Only 50 μL sample at 0.006 g/ml is required for SARA fractionation. • Low sample concentration increased lifetime and separation efficiency of the columns. • Solvent use is reduced to 0.1L from 2.5 to 3.0 L, lowering environmental impact. Fractionation of complex hydrocarbon mixtures such as bitumen into their constituents based on their polarizability and solubility is essential in the detailed characterization of petroleum fluids. The development of fast and reliable analytical techniques for petroleum characterization has been the focal point of fractionation studies. The separation of Saturate, Aromatic, Resin and Asphaltene (SARA) fractions using our previously reported automated fractionation technique relied on material balance in estimating the saturates, which could introduce inherent errors in determining all fractions. Furthermore, the previous technique was developed using concentrated samples, which could exacerbate the material balance error. Here, we have improved and optimized our previously developed technique to address these shortcomings. This enhancement involves full automation of the analytical detection process for all fractions and optimizing the measurement operation, sample concentration, and volumes. This led to the development of a fully automated analytical instrument and optimized technique for rapidly and efficiently separating and detecting four subfractions of complex hydrocarbon mixtures, including saturates, aromatics, resins, and asphaltenes. In this technique, only 50 μ L of a sample with an oil concentration of 0.006 g/ml is required for separating oil SARA fractions by injecting through three columns packed with specific stationary phases. Initially, the asphaltene separation occurs in a ground polytetrafluoroethylene (PTFE) packed column in an excess volume of n-pentane. Then, the pentane-soluble maltene passes through standard ZORBAX RX-SIL- and ZORBAX CN-packed columns, where chromatographic separation of the resins and aromatics occurs. The highly polar resins are adsorbed on the ZORBAX CN column, whereas the moderately polar components (i.e., aromatics) are retained on the ZORBAX RX-SIL column. The saturate fraction is not retained on the columns and is directed to the refractive index detector (RID) for quantification. After separating each fraction, in the last step, asphaltenes, aromatics and resins are eluted from their respective columns by injecting toluene and forwarded to an ultraviolet − visible (UV − vis) absorbance to quantify each fraction. The results of the SARA-HPLC technique exhibited excellent accuracy and reproducibility; the average deviation of saturate, aromatic, resin, and asphaltene fractions are 1.29, 2.81, 3.75, and 1.04 wt%, respectively. This technique delivers SARA fractionation results with high repeatability within 1.65 wt% average deviation. The enhanced automated approach for SARA separation demonstrates superior efficiency by employing less concentrated samples, reduced volumes of oil samples and solvents, and significantly shorter testing times compared to the conventional gravimetric manual method. [ABSTRACT FROM AUTHOR]

• A LC system was constructed with a miniaturized photometric detector and a microfluidic chip. • The Z-shaped cell design increases the effective optical path length. • The Z-shaped cell and column are on the same chip without a pipeline connection. • The microchip can be filled with cation exchange resin and C18 particles. In recent years, miniaturized analytical instruments have been developing to meet the needs of portable and rapid analysis. The key of miniaturized analytical equipment is the miniaturization and integration of functional modules. This paper aims to develop a miniaturized photometric detector and separation microfluidic chip for a liquid chromatography (LC) system. The detector uses a light-emitting diode to emit ultraviolet light, which is collimated by an internal double lens. A Z-shaped flow cell with a long optical path is designed and fabricated in the separation microfluidic chip with a three-layer structure, which provides a tubing-free connection between the separation and detection unit. Detector performance is evaluated using hemoglobin (Hb) samples, with an upper limit of detection linearity (95 %) of 0.345 AU and stray light level as low as 0.08 %. Additionally, the microchip channel can be filled with cation exchange resin and C18 particles. Finally, an ion LC system and a reversed-phase LC system were constructed based on the miniaturized photometric detector and two microchips with different packed columns, respectively, and were successfully used in the separation and detection of two metabolic markers (glycated hemoglobin or bilirubin). The results of this study are expected to facilitate the development of a portable LC system and their application in community health services and family health management of chronic diseases. [ABSTRACT FROM AUTHOR]

• Positively charged surface C 18 phases were evaluated for LC-MS of peptides. • Ionic interaction, retention, loading capacity, and separation were examined. • Effect of formic acid concentration on separation and MS sensitivity was evaluated. • MS signal intensity improved upon minimizing formic acid concentration. • Suitable stationary phase is essential to exploit the improved MS signal. We have recently demonstrated the ability of a C 18 stationary phase with a positively charged surface (PCS-C 18) to provide superior chromatographic separation of peptides using mobile phase acidified with a mere 0.01 % formic acid, significantly improving MS sensitivity. Here, we examined three columns packed with different PCS-C 18 phases using the MS-favorable mobile phase acidified with low formic acid concentrations to establish the impact of separation performance and better MS sensitivity on peptide identifications. The surface charge interaction was evaluated using the retention of nitrate. The highest interaction was observed for the AdvanceBio Peptide Plus column. A surface charge-dependent shift in the retention time of peptides was confirmed with a change in formic acid concentration in the mobile phase. The separation performance of the columns with MS-favorable mobile phase acidified with low concentrations of formic acid was evaluated using well-characterized peptides. The loading capacity was assessed using a basic peptide with three lysine residues. Good chromatographic peak shapes and high loading capacity were observed for the Acquity Premier CSH C 18 column, even when using a mobile phase acidified with 0.01 % formic acid. The extent of improvement in peptide identification when using reduced formic acid concentration was evaluated by analyzing the tryptic digest of trastuzumab and tryptic digest of whole bacteria cell lysate. Each column provided improved MS signal intensity and peptide identification when using the mobile phase with 0.01 % formic acid. The ability of the Acquity Premier CSH C 18 column to provide better separation of peptides, even with a reduced formic acid concentration in the mobile phase, boosted MS signal intensity by 65 % and increased the number of identified peptides from the bacterial sample by 19 %. Our study confirms that significant improvement in the proteomic outputs can be achieved without additional costs only by tailoring the chemistry of the stationary phase to the composition of the mobile phase. Our results can help researchers understand the retention mechanism of peptides on the PCS-C 18 stationary phases using low-ionic strength mobile phases and, more importantly, select the best-suited stationary phases for their LC-MS proteomic applications. [ABSTRACT FROM AUTHOR]

Slalom chromatography (SC) was discovered in 1988 for analyzing double-stranded (ds) DNA. However, its progress was impeded by practical issues such as low-purity particles, sample loss, and lack of a clear retention mechanism. With the rise of cell and gene therapies and the availability today of bio-inert ultra-high-pressure liquid chromatography (UHPLC) columns and systems, SC has regained interest. In SC, the elution order is opposite to that observed in hydrodynamic chromatography (HDC): larger DNA molecules are more retained than small ones. Yet, the underlying SC retention mechanism remains elusive. We provide the physicochemical background necessary to explain, at a microscopic scale, the full transition from a HDC to a SC retention mechanism. This includes the persistence length of the DNA macromolecule (representing DNA stiffness), their relaxation time (τ R) from the non-equilibrium contour length to the equilibrium entropic configuration, and the relationship between the mobile phase shear rate (〈 γ ̇ 〉) in packed columns and the DNA extended length. We propose a relevant retention model to account for the simultaneous impact of hydrodynamic chromatography (HDC) and SC on the retention factors of a series of large and linear dsDNAs (ranging from 2 to 48 kbp). SC data were acquired using bio-inert MaxPeak T M Columns packed with 1. 7 μ m BEH T M 45 Å, 1. 8 μ m BEH 125 Å, 2. 4 μ m BEH 125 Å, 5. 3 μ m BEH 125 Å, and 11. 3 μ m BEH 125 Å Particles, an ACQUITY T M UPLC T M I-class PLUS System, and either 1 × PBS (pH 7.4) or 100 mM phosphate buffer (pH 8) as the mobile phase. SC is a non-equilibrium retention mode that is dominant when the Weissenberg number (W i = 〈 γ ̇ 〉 τ R ) is much larger than 10 and the average extended length of DNA exceeds the particle diameter. HDC, on the other hand, is an equilibrium retention mode that dominates when W i < 1 (DNA chains remaining in their non-extended configuration). Maximum dsDNA resolution is observed in a mixed HDC-SC retention mode when the extended length of the DNA is approximately half the particle diameter. This work facilitates the development of methods for characterizing various plasmid DNA mixtures, containing linear, supercoiled, and relaxed circular dsDNAs which all have different degree of molecular stiffness. • Retention mechanism of dsDNA by slalom chromatography physically revisited. • SC fundamentals are based on shear flow and stiffness/relaxation of DNA. • Product of shear rate by DNA relaxation time (Weissenberg number) is critical. • SC dominant retention mode when the eluent/DNA Weissenberg number > 10. • HDC dominant retention mode when the eluent/ DNA Weissenberg number < 1. [ABSTRACT FROM AUTHOR]

• A conventional HPLC instrument was adapted for 1–10 µL/min flow rates operation. • Active flow splitter and capillary UV–vis cell construction details. • Capillary-scale flow precision with an arduino Uno-based splitter. • Efficient capillary-scale detection compatible with conventional detectors. This study introduces a feasible approach for utilizing a conventional High-Performance Liquid Chromatography (HPLC) instrument at the capillary scale (1 - 10 µL/min). The development of an active flow splitter and an adapted UV-visible (UV–vis) detection cell are described. The system employs an Arduino Uno board to monitor a flow sensor and control a stepper motor that automates a split valve to achieve capillary-scale flow rates from a conventional pump. A capillary UV–vis cell compatible with conventional detectors, featuring an optical path length with a volume of 14 nL, was developed to address the detection challenges at this scale and minimize extra column band broadening. The system performance was assessed by a lab-packed LC capillary column with 0.25 mm x 15 cm dimensions packed with 3.0 µm C18 particles. Model compounds, particularly polycyclic aromatic hydrocarbons (PAHs), were employed to assess the functionality of all developed components in terms of theoretical plates, resolution, and band broadening. The proposed system is a profitable, reliable, and cost-effective tool for miniaturized liquid chromatography. [ABSTRACT FROM AUTHOR]

A lithium titanate-decorated Ti 3 C 2 T x MXene (LTO-MX) composite was synthesized through etching and alkali processes, and subsequently immobilized using polyacrylonitrile (PAN) polymer via a phase inversion method. In the batch study, the strontium adsorption behavior followed the Redlich-Peterson isotherm and the pseudo-second-order kinetic models. The maximum adsorption capacity for strontium reached 24.05 mg/g. Furthermore, a continuous fixed-bed column study was performed using the LTO-MX PAN beads to remove strontium from aqueous solutions. The dynamic behavior of column adsorption was examined under various operating parameters such as initial strontium concentration, flow rate, and bed height. Dynamic modeling was employed to describe adsorption breakthrough properties based on these experimental data. Both the Thomas and Yoon-Nelson models accurately simulated the breakthrough curves. The proposed mechanisms for strontium adsorption included encapsulation, electrostatic attraction, cation exchange, and surface complexation. These results demonstrate the effectiveness of LTO-MX PAN beads as adsorbents for the continuous removal of strontium from radioactive wastewater. [Display omitted] • A lithium titanate-decorated Ti 3 C 2 T x MXene (LTO-MX) composites were synthesized. • The synthesized LTO-MX polyacrylonitrile (PAN) beads efficiently removed Sr2+ in aqueous solution. • A continuous fixed-bed column packed with LTO-MX PAN beads was employed for Sr2+ removal. • LTO-MX PAN beads performed excellently in extreme acidic conditions. • Four mechanisms collectively contribute to the effective removal of strontium ions by the LTO-MX PAN beads. [ABSTRACT FROM AUTHOR]

[Display omitted] • Micro polymer inclusion beads contained di-(2-ethyl-hexyl) phosphoric acid and PVC. • For the first time these beads were packed into a separation column. • Its performance was investigated with the successful separation of La3+ from Gd3+. • The column individually separated Nd3+ and Dy3+ from a permanent magnet digest. • Thermogravimetric analysis demonstrated negligible extractant loss from the beads. A column filled with micro polymer inclusion beads (µPIBs) was developed and investigated for the first time. The µPIBs were composed of 60 wt% di-(2-ethyl-hexyl) phosphoric acid (D2EHPA) and 40 wt% poly(vinyl chloride) (PVC) and the column was used for the separation of ions of rare earth elements (REEs) from synthetic solutions and the digest of end-of-life (EOL) rare earth permanent magnets (REPMs). This µPIB packed column was successfully applied to separating La3+ from Gd3+, as representatives of the light and middle REEs, previously achieved by us using a polymer inclusion membrane (PIM) containing the same chemical components as the µPIBs used in this study. The results obtained demonstrated the feasibility of the µPIBs packed in a column for light and middle REE ion separation similarly to their PIM counterpart. The separation potential of the µPIB packed column was further demonstrated by the selective recovery of Nd3+ and Dy3+ from an EOL REPM digest in 2 M sulfuric acid which also contained Fe3+, Co2+, and Ni2+. Nd3+ and Dy3+ could be selectively extracted from the diluted to 0.03 M sulfuric acid digest after the addition of ascorbic acid which reduced Fe3+ to Fe2+. Nd3+ and Dy3+ were separated via selective back-extraction from the µPIB-column using 0.3 and 2 M sulfuric acid receiving solutions, respectively. Thermogravimetric analysis of the µPIBs, before and after application in the µPIB-column, indicated negligible D2EHPA loss after six processing cycles. Thus, these results demonstrated the strong potential of the proposed µPIB-column method for the sustainable recovery of REEs from electronic waste such as REPMs. [ABSTRACT FROM AUTHOR]

• In contrast to gas-phase systems, the theory and practice of determining effective diffusion coefficients in porous solid materials immersed in liquids is a challenge. • A method for the termination of effective diffusion coefficients packed beds was proposed. • Experiments were carried out with steps response technique to reveal the role of diffusion, adsorption and dispersion in packed beds. • A mathematical model was proposed and verified with experimental data. Many industrially relevant chemical processes are affected by the liquid-phase diffusion resistance in porous materials, for example in heterogeneous catalysts. Therefore, reliable experimental methods for the determination of effective diffusion coefficients in porous structures are highly desirable. In this work, a method was developed to study the internal diffusion effects in porous media by step response experiments with tracers injected to fixed beds filled with porous particles and inert material. The tracer responses were recorded at the outlet of the bed by UV–vis spectrometry. Ethanol was used as the tracer and water as the solvent. Porous aluminum oxide particles were selected as the model material. The step responses were described with a dynamic axial dispersion model, i.e. partial differential equations for the inert and catalyst sections of the bed. The partial differential equations describing the model were discretized with finite differences and the resulting ordinary differential equations were solved numerically with a solver for stiff ordinary differential equations. From the experimental data, the dispersion coefficients of the bed and the effective diffusion coefficient in the porous aluminum oxide particles were successfully determined by non-linear regression analysis. The values of the effective diffusion coefficents had a good agreement with the liquid-phase diffusion coefficients estimated from correlations. The method is applicable for any porous material. [ABSTRACT FROM AUTHOR]

[Display omitted] • Utilization of supercritical fluid chromatography (SFC) in food product analysis toward cannabinoid content. • Elucidation of possible fragmentation patterns based on the high-resolution mass spectra (HRMS/MS). • Comprehensive optimization of operating conditions of the hyphenated SFC-HRMS/MS system. • High selectivity and sensitivity of the developed method. • Suitability of the developed method in the analysis of hemp tea infusions. A growing number of papers suggest the positive action of cannabinoids in the treatment of several diseases, which is ascribed to the ability of phytocannabinoids to affect the human endocannabinoid system. In particular, this activity is characteristic of CBD, a non-psychoactive variation of 9-THC. It initiated a trend in the manufacturing of edible and cosmetic products containing CBD that can be easily acquired in drugstores. However, the composition of such products has rarely been tested. Hence, there is a need for data regarding their safety. Considering the possibility of cannabinoid interconversions as well as the complexity and diversity of edible products' matrix, their analysis requires a suitable preparation and cleanup procedure. In this paper, the perspective of the application of Supercritical Fluid Chromatography (SFC) coupled to High-Resolution (HR) Quadrupole-Time of Flight (Q-TOF) tandem mass spectrometry (MS/MS) with electrospray ionization (ESI) in quality control of cannabis-containing food products was examined. The focus is on six neutral (CBD, 9-THC, CBC, CBG, CBN, and THCV) and three acidic (CBDA, THCA, and CBGA) cannabinoids. The study covers the thorough optimization of conditions for chromatographic separation with the use of the supercritical CO 2 (scCO 2)-based mobile phase and the working parameters of MS/MS detection with the elucidation of fragmentation patterns. Thanks to the utilization of scCO 2 , a short analysis time of 17 min., high intensity and small width of peaks, as well as low consumption of toxic organic solvent have been achieved at the 2-EP column with a 5 μm grain size. To reach such performance in LC, the utilization of more expensive columns packed with sub-2 μm particles is needed. In the case of the solvent matrix, the LOD was equal to 8 ng mL−1 for CBDA, THCA, and CBGA, 15 ng mL−1 for CBG and THCV, and 21 ng mL−1 for THC, CBD, CBC, and CBN. In the case of tea, an LOD of 25 ng mL−1 for acidic and 75 ng mL−1 for neutral cannabinoids has been obtained. The accuracy and precision were within the ± 15 % tolerance limit. Finally, the devised protocol has been applied for cannabinoid determination in hemp tea infusions. [ABSTRACT FROM AUTHOR]

Calcium sensing receptor (CaSR) has become the novel target of treating osteoporosis with herbal medicine Ligustri Lucidi Fructus (LLF), however, the bioactive compounds responsible for anti-osteoporosis are hard to clarify due to the complexity and diversity of chemical constituents in it. Herein, the immobilized CaSR column was packed with stationary phase materials, which were derived from integrating CLIP-tagged CaSR directly out of crude cell lysates onto the surface of silica gels (5.83 mg/g) in a site-specific covalent manner. The column had a great specificity of recognizing agonists and kept a good stability for at least 3 weeks. The two compounds from LLF extract were screened and identified as olenuezhenoside and ligustroflavone using the immobilized CaSR column in conjunction with mass spectrometry. Molecular docking predicted that both compounds were bound in venus flytrap (VFT) domain of CaSR by the formation of hydrogen bonds. Cellular results showed that both compounds exhibited the distinct osteogenic activity by enhancing the proliferation, differentiation and mineralization of osteoblastic cells. Our study demonstrated that, the immobilized protein column enables to screen the bioactive compounds rapidly from herbal extract, and the newly discovered natural product ligands towards CaSR, including olenuezhenoside and ligustroflavone, will be the candidates for the treatment of osteoporosis. • Establishing a rapid drug-screening method for Traditional Chinese Medicine. • Screening the bioactive compounds from herbal extract without the time-consuming isolation. • The newly discovered CaSR-targeted ligands exhibit osteogenesis effect. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA) has received extensive attention because of its ubiquitous presence in the aqueous environmental phase and concerns of its impact on human health. An economical and effective adsorption method is in demand to help resolve the issue. In this study, a polyamine-functionalized polychlorotrifluoroethylene-ethylene polymer coated activated carbon (AC) was synthesized via a two-step reaction. The fluoropolymer based on the repeating unit ethylene-chlorotrifluoroethylene (ECTFE) was applied as the binding medium to connect activated carbon with polyethyleneimine (PEI). Hence a dual grafted activated carbon-based sorbent AC-ECTFE-PEI was generated. Through the adsorption evaluation of packed columns by on-line detection flow analysis, the optimum synthetic stoichiometry parameters to produce AC-ECTFE-PEI, based on the longest adsorption breakthroughs, were determined to be the 5:2 AC/ECTFE and 1:1 AC-ECTFE/PEI mass ratios. The new adsorbent has shown a strongly enhanced initial adsorption breakthrough to PFOA compared to AC, 270 min vs. 110 min, under the same adsorption conditions. AC-ECTFE-PEI was also characterized by attenuated total reflectance infrared spectroscopy, BET surface area analysis, and scanning electron microscopy. The functional group alterations during the reactions and the morphology information of the sorbent have also been elucidated. The Thomas, Adams-Bohart, and Yoon-Nelson models respectively were used to describe the adsorption behavior, indicating an PFOA adsorption capacity of 380 mg/g sorbent, 120 mg/L sorbent column, and a 50% average breakthrough time of 350 min for 100 mg/L PFOA removal, under a 1 mL/min flow rate and a 2 cm bed height. The regeneration study of AC-ECTFE-PEI of more than five adsorption-desorption cycles indicates good sustainability and stability. Both electrostatic and hydrophobic interactions of PFOA were justified using selective solvent compositon of the mobile phase as the two main adsorption mechanisms. The electrostatic forces of PFOA on AC-ECTFE-PEI, AC-ECTFE, and AC were also evaluated by their zeta-potential values. [Display omitted] • Activated carbon adsorbent coated with Halar fluoropolymer and covalently modified with polyethyleneimine. • PFOA adsorption breakthrough studies by packed column flow analyses with on-line UV detection. • Adsorption mechanism based on mobile phase solvent composition included both hydrophobic and electrostatic interactions. • Regeneration study indicated good sorbent PFOA recovery averaging 80% for five cycles. [ABSTRACT FROM AUTHOR]

Considerable work has been done on method standardization for experimental characterization of column packings used in absorption processes. A detailed framework for determination of packing hydraulics as well as gas- and liquid-side volumetric mass transfer coefficients (k G a and k L a) has been established. Packing characterization experiments in large diameter columns result in high equipment and operating costs. Accurate extrapolation of packing properties from experiments in smaller diameter columns would therefore be highly desirable. However, diameter influence is currently not completely understood, making further work necessary. In this work, experiments for the determination of k G a and k L a values were carried out and evaluated independently in two plants (inner diameters 422 and 150 mm). Results from measurements conducted with three metal packings RSP 250Y, RMP N 250X and RMP N 250Y are in good agreement with existing literature data. k G a was found to be dependent on column diameter with larger diameters leading to increased k G a values. The overall effect (approx. 15 %) is consistent with previous works, suggesting the possibility of deriving appropriate scaling factors once the findings are validated by a larger sample size. No clear dependence of k L a values on diameter was found with deviations significantly smaller than for k G a measurements. [Display omitted] • Three column packings are surveyed using standardized methodology. • Results from two different column diameters (150 and 422 mm) are compared. • k G a values are found 15 % lower at the smaller column diameter. • No influence of column diameter on k L a values is observed. [ABSTRACT FROM AUTHOR]

Uncertainties due to maldistribution in the operation of packed columns are one of the major issues in column design. Thus, thorough knowledge of the liquid distribution and the mass transfer processes within the packed bed is necessary. Models able to predict maldistribution are crucial for avoiding extensive experimental investigations. In the present study, the TUM-WelChem cell model is expanded by the simulation of heat and mass transfer in a packed column operated as a cooling tower. The simulation approach is based on experimental data obtained at the Technical University of Munich using a Ø0.634 m random packed column. Temperature profiles and global outlet values of liquid and gas temperatures along with the humidities are evaluated and discussed for the Hiflow® ring 50–6 polypropylene. The presented study provides insight into the applicability of the heat and mass transfer calculation by validating the simulation results with experimental data. [Display omitted] • Simulation of heat and mass transfer in a random packed column using a cell model. • Usage of the TUM-WelChem cell model as basis for liquid distribution. • Sequential and simultaneous calculation of the heat and mass transfer phenomena. • Bayesian optimization for correlations for heat and mass transfer coefficients. • Comparison of simulated temperature profiles and outlet values with experiments. [ABSTRACT FROM AUTHOR]

This work presents a model for the prediction of the separation efficiency of packed columns filled with structured metal sheet packings and stacked packings of different materials and types for distillation and absorption processes. For model validation, packings of sheet metal, ceramic and plastic of various shapes and sizes such as Mellapak, Montz-Pack, Gempak, Ralu-Pak, metal and ceramic Impulse packing IP50 and IP100 and various other types of regularly arranged packings such as 50 mm ceramic Pall rings, 25 and 50 mm metallic Białecki rings, 50 mm PSL rings made of metal and 50 mm plastic Hiflow were investigated using absorption and distillation test systems under low pressure and atmospheric conditions in columns with diameters ranging between 0.15 and 0.60 m. The model was validated in the operating range below the flooding line for F V 0.90 F V,Fl and for turbulent liquid flow Re L ≥ 2. The comparison of the predicted values with measured data presented in this work has confirmed that the presented model is suitable for determining the separation efficiency not only for sheet metal structured packing, but also for regularly arranged stacked packings filled with packing commonly used as random packing for absorption and distillation systems under vacuum and normal pressure. The calculation example shows also the application of the presented model for predicting the separation efficiency n t /H of sheet metal packings and stacked packings with a specific packing area a from 60 up to 500 (750) m²/m³ for distillation processes under low and normal pressure. • A model for separation efficiency for structured and stacked packing is derived. • The model was validated using distillation and absorption test systems. • The model is valid up to a relative gas load of 90% of flooding for ReL ≥ 2. • The channel angle of a packing does not influence liquid phase mass transfer. [ABSTRACT FROM AUTHOR]

• Approximate analytical solutions for arbitrary dynamic inlet boundary condition of the thermocline tank are obtained. • The effects of typical sinusoidal oscillating parameters on the transport phenomena in the packed bed are investigated. • Oscillating boundary conditions lead to degradation of thermal stratification and enhanced heat transfer simultaneously. • General optimum oscillating frequency equation for the charging/discharging process with oscillating inlet velocity and temperature condition is proposed. The dynamic thermal performance of single-tank thermocline (STTC) thermal energy storage (TES) system under oscillating boundary conditions (BCs) during cloud cover or start-up period is critical to the safety and efficiency of the whole concentrating solar power (CSP) plant. In this study, the approximate analytical solution of the STTC TES system under oscillating velocity and temperature BCs are derived from the one dimensional-two phase (1D-2P) models, which can be applied in arbitrary realistic BCs with Fourier decomposition method. After model validation with dynamic experimental data, the effects of typical sinusoidal oscillating parameters on packed bed transport phenomena and TES efficiency were investigated. It is found both of the oscillating inlet velocity and temperature lead to degradation of thermal stratification, such as outlet temperature fluctuation, while it also causes enhanced heat transfer effect and increased charging/discharging cut-off efficiency. Cut-off efficiency increases with amplitude of oscillating inlet velocity or oscillating inlet temperature, while for oscillating frequency there is optimum value. On that basis, the general optimum equation of cut-off efficiency and oscillating frequency is proposed, and the relative error is smaller than 1.0% when outlet temperature is larger than 0.011 for the discharging process with oscillating inlet velocity BC and smaller than 3.2% for oscillating inlet temperature BC. Moreover, the thermocline region movement velocity increases with inlet velocity for oscillating inlet velocity BC and decreases with oscillating frequency for oscillating inlet temperature BC. [ABSTRACT FROM AUTHOR]

In this study, the hydrodynamics characteristics of packed column with structured sinusoidal corrugated sheets packings were investigated by computational fluid dynamics (CFD) modeling and simulation method. The proposed CFD model was first validated by comparing simulation results with those of experimental data in terms of pressure drop under different inlet gas velocities. Then the effects of wave length, amplitude, angle and placement method on dry pressure drop were studied by control variable method. The relationship between F factor and pressure drop with different packing structures were investigated. The flow fields of pressure and velocity were analyzed and then used to calculate the resistance coefficient of structured packings. This simulation study can contribute to the evaluation and optimization of multiphase flow characteristics and the mass transfer performance of packed column. • Geometry structure highly influences the hydrodynamic performance. • RNG k-ε model is adaptable for corrugated sheets packings simulation. • Resistance coefficient will converge to a constant as Reynold number increases. • Pressure drop declines with wavelength, amplitude and corrugated angle increases. [ABSTRACT FROM AUTHOR]

Solar-operated distillation unit (SDU) was designed and fabricated for extraction of valuable essentials from aromatic crops with a reduced cost of operation without carbon-credits to the environment. It comprised of distillation still, mesh grid frame, packed column, condenser, oil receiver, energy meter, resistive heating elements, and solar panels. This improved SDU can process 20 kg of aromatic crops in a batch type of operation. Resistive heating elements (4.5 kW) with controllers powered by the solar photovoltaic panel (5 kW) were used to produce the uniform steam generation within 20 min. This produced steam was adequate for continuous distillation (∼3 h) of aromatic crops to collect valuable essentials in an oil receiver. The total power consumed by the SDU in carrying out the distillation operation was calculated (13.5 kWh). The extraction studies of Ocimum cultivars (CIM-Shishir, 100 and 102) through SDU and Clevenger-type apparatus (standard set) revealed that the SDU process was yielded improved essential oil (0.36–0.73%). GC-FID and GC/MS analyses divulged that the essential oil obtained through SDU was superior in quality with improved percentage of biomarkers such as linalool (upto 62.8%) and methyl chavicol. Designed SDU has saved about 20 kg of wood per batch as compared to practiced wood-based distillation operation. [Display omitted] [ABSTRACT FROM AUTHOR]

1,4-dihydropyridine (DHP) scaffold occupies a prominent position among all heterocyclic compounds owing to its versatile pharmacological properties, particularly its well-known calcium channel blocking activity. In the quest of developing new calcium channel blockers, fifty seven 5-oxo-hexahydroquinoline (HHQ) derivatives carrying DHP framework in a condensed ring system were recently synthesized as racemic mixtures. Due to their potential as drug candidates, enantiomers arising from the asymmetric center at the C-4 position of the HHQ ring were separated. Four modern columns packed with 2.7 µm superficially porous particles bonded with a chiral selector were used. The chiral selectors were three macrocyclic glycopeptide selectors: vancomycin, teicoplanin, and a macrocyclic derivative called nico. The fourth bonded selector was the dinitrobenzamido-tetrahydrophenanthrenyl derivative called Whelko. The four chromatographic modes were assayed with the mobile phase compositions: reversed phase with acetonitrile/buffer 30/70 %v/v, normal phase with hexane/ethanol 80/20 %v/v, and subcritical fluid chromatography with CO 2 /methanol 80/20 %v/v at 25 °C. The WhelkoShell column was the most effective in separating this set of 57 compounds. Several enantioresolution factors passed 20 with enantioselectivity ratios higher than 4. Molecular modeling showed that the compounds had a T-shape that fitted well the molecular structure of the WhelkoShell selector in the normal or subcritical modes. Additionally, seven compounds had a second chiral center. The NicoShell column was able to separate all four stereoisomers of these compounds in the reversed phase mode. The preparative production of pure enantiomers of these compounds would be straightforward using the WhelkoShell column in the subcritical mode. [Display omitted] • The enantiomers of 57 chiral potential bioactive hexahydroquinoline (HHQ)-based compounds were separated. • Four superficially porous chiral columns were used in three modes: reversed phase, normal phase and supercritical fluid. • The WhelkoShell column was outperforming the three other chiral columns. • Structural similarities between the HHQ compounds and the WhelkoShell selector may explain the results. [ABSTRACT FROM AUTHOR]

This study investigates the behavior of adsorbent solids within three-dimensional networks of biopolymers. Two chemically different herbicides, 2,4-D and paraquat (PQ) were employed as test molecules. Alginate (ALG) hydrogels in bead form were synthesized, incorporating activated carbon (PSCA) and montmorillonite clay (MMT) simultaneously and in varying proportions, resulting in multicomponent beads. The Langmuir isotherm parameters, K L (L mmol−1) and q max (mmol g−1), in the adsorption of herbicides on beads with an increasing amount of montmorillonite (MMT) were as follows: For PQ, K L values were 10.709, 61.951, 162.33, 223.27, and q max values were 0.0711, 0.1484, 0.2135, 0.2497. For 2,4-D, K L values were 13.360, 8.3234, 7.4126, 5.4308, and qmax values were 0.9529, 0.7096, 0.6534, 0.5881. The values clearly demonstrates that, even when solids are mixed in the hydrogel network, their reactive sites remain exposed, interacting with molecules to which they have greater affinity. Adsorption was also investigated on identical materials using binary mixtures of herbicides, revealing trends similar to those observed for individual solutions. Moreover, it was demonstrated that the adsorption capacity of multicomponent beads is equivalent to that achieved by proportionally mixing beads synthesized exclusively with clay or activated carbon. This suggests the tangible possibility of creating on-demand adsorbents by synthesizing distinct hydrogels, each incorporating a specific solid. Subsequently, drying, storing, and mixing them based on the target contaminant for retention are feasible. Finally, a column was packed with a proportional mixture of beads and successfully retained PQ and 2,4-D using a flow-through system. [Display omitted] • PSAC and MMT in alginate beads preserves their adsorption capacity. • Multicomponent beads are effective adsorbents of 2,4-D, PQ and binary systems. • Alginate does not alter the reactivity of the adsorbent surface sites. • Multicomponent beads equal the adsorption capacity of mixed single-component beads. • The mixtures of beads exhibited excellent performance when packed in columns for flow systems. [ABSTRACT FROM AUTHOR]

Slalom chromatography (SC) re-emerged in 2024 due to the availability of low adsorption ultra-high pressure liquid chromatography (UHPLC) packed columns/instruments and large modalities being investigated in the context of cell and gene therapies. The physico-chemical principles of SC retention combined with hydrodynamic chromatography (HDC) exclusion have been recently reported. In SC, DNA macromolecules are retarded because: (1) they can be stretched to lengths comparable to the particle diameter, and (2) their elastic relaxation time is long enough to maintain them in non-equilibrium extended conformations under regular UHPLC shear flow conditions. Here, a quantitative HDC-SC retention model is consolidated. A general plate height model accounting for the band broadening of long DNA biopolymers along packed beds is also derived for supporting method development and predicting speed-resolution performance in SC. For illustration, the chromatographic speed-resolution properties in SC are predicted for the separation of specific critical pairs (4.0/4.5, 10/11, and 25/27 kbp) of linear dsDNA polymers. The calculations are performed for two available custom-made particle sizes, d p = 1.7 and 2. 5 μ m , at a constant pressure of 10,000 psi. The predictions are directly validated from experimental data acquired using low adsorption MaxPeak TM 4.6 mm i.d. Columns packed with 1. 7 μ m BEH TM 45 Å (15 cm long column) and 2. 5 μ m BEH 125 Å (30 cm long column) Particles, and by injecting six linear dsDNAs (λ DNA-Hind III Digest). The LC system is very low dispersion ACQUITY TM UPLC TM I-class PLUS System, and the mobile phase is a 100 mM phosphate buffer at pH 8. Maximum resolution is always achieved when the average extended lengths of linear dsDNAs are equal to a critical length, which is proportional to the particle diameter and to the square root of the applied shear rate. Most advantageously, the experimental results reveal that the relaxation times of linear dsDNAs observed under shear flow conditions are two orders of magnitude shorter than those expected in the absence of flow: this enables the detection of the longest linear dsDNAs up to 25 kbp without irremediable loss in column performance. Finally, the retention-efficiency model elaborated in this work can be used to rapidly anticipate and develop methods (selection of particle size, column length, and operating pressure) for any targeted DNA and time-resolution constraints. • Model of selectivity factors between linear dsDNA biopolymer is consolidated. • Specific mass transfer resistance in slalom chromatography is studied. • Resolution factors depend on particle diameter, column length, and speed. • Optimum resolution power predicted for a critical dsDNA chain length. • The predicted optimum resolution factors match the experimental results well. [ABSTRACT FROM AUTHOR]

[Display omitted] • Epoxidation of non-edible vegetable oil was conducted with high conversion and high selectivity. • Continuous operation mode was applied. • A packed column reactor was used in the experiments. • The experimental data were successfully described by a bifacial and dynamic mathematical model. Epoxides are an attracting class of molecules thanks to their highly reactivity given by the strain three-terms ring. For this reason, epoxides are important intermediates for the synthesis of several organic compounds. Epoxidized vegetable oils (EVOs) obtained from biomass, represent a noteworthy source for valuable chemicals. EVOs have already been successfully applied as stabilizers and scavengers in PVC and, after follow-up reactions, as plasticizers in PVC as well as intermediates to produce polyurethane. However, the industrial production of EVOs still relies on a cumbersome and dangerous semibatch technology, limiting the productivity of this platform chemical. A new, continuous and safe technology for the production of EVOs from non-edible vegetable oils was developed in this work. Cardoon seed oil was used as a model system. A continuous reactor configuration consisting of a packed column, was constructed and its performance was successfully demonstrated, leading to double bond conversions exceeding 95 % and epoxide selectivities 90 % at 40 °C, clearly exceeding the performance of the current semibatch process. The reaction system was studied in detail and a dynamic liquid–liquid reactor model was developed, based on the intrinsic kinetics, interfacial mass transfer and axial dispersion effects. [ABSTRACT FROM AUTHOR]