Metal Solvent Research Articles

Features of Generation, Propagation and Application of Special Ultrasonic Impulses in Viscous Liquids

An exact numerical and approximate analytical description of solitary acoustic pulses with a large difference in spatial gradients of parameters in different directions has been obtained in viscous liquids using this small parameter. The method of special initial-boundary conditions obtained during analyzing the hydrodynamic equations has been applied to describe the peculiarities of this nonlinear phenomenon. Waves of this type exist in the presence of two- or three-dimensional inhomogeneity of the initial disturbances and retain a spatial structure along the direction of propagation when traveling long distances. At the same time, it is possible to regulate the pressure drop and the speed of the acoustic signal, which creates unique conditions for a special force effect or information transmission. The efficiency of their use in such processes as metal dissolution, solvent extraction and mass transfer under the conditions of resonance exposure of ultrasound was evaluated. Fine details of exciting the nonlinear impulse with the necessary properties have been analyzed to demonstrate a possible way to a new technology of successfully treating any different specimens, materials and constructions for a long distance between the source of radiation and the position of the treatment. The use of such pulses opens up new opportunities for remote acoustic force impact on various objects, as well as for the transmission of information.

Enhanced salt content and stabilized bilayer passivation interphase toward long-life and high-safety anode-free lithium battery

Anode-free lithium batteries (AFBs) offer optimal energy density, low cost, and simple manufacturing, making them desirable for next-generation high-energy-density batteries. However, the continuous consumption of electrolyte and Li metal through the undesirably constructed solid electrolyte interphase (SEI) significantly limits the cycling and thermal stability of AFBs. To address this challenge, dual-solvent localized high-LiFSI salt concentration electrolytes (DS-LHCEs) are designed by the addition of sulfolane (SF) due to its higher LiFSI solubility and highly consistent Li+-solvent binding energy with DME. High LiFSI content increases the salt-to-solvent concentration, decreases the amount of free solvent molecules, and restricts the side reaction between the free solvent and Li metal. As a result, a flat and dense Li metal with a robust LiF-rich SEI is deposited on Cu foil. Moreover, the introduction of trioxane (TO) constructs a high-strength outer organic SEI layer, which protects the weak grain boundaries of the inner inorganic SEI layer, further enhancing the stability of the Li metal anode. This results in assembled AFB pouch cells with a superior lifetime (206 cycles with 80 % capacity retention) and a much higher onset self-heating temperature (119 °C vs. 58 °C in the DME-based baseline electrolyte).

Transition Metal-Gallium Intermetallic Compounds with Tailored Active Site Configurations for Electrochemical Ammonia Synthesis.

Gallium (Ga) with a low melting point can serve as a unique metallic solvent in the synthesis of intermetallic compounds (IMCs). The negative formation enthalpy of transition metal-Ga IMCs endows them with high catalytic stability. Meanwhile, their tunable crystal structures offer the possibility to tailor the configurations of active sites to meet the requirements for specific catalytic applications. Herein, we present a general method for preparing a range of transition metal-Ga IMCs, including Co-Ga, Ni-Ga, Pt-Ga, Pd-Ga, and Rh-Ga IMCs. The structurally ordered CoGa IMCs with body-centered cubic (bcc) structure are uniformly dispersed on the nitrogen-doped reduced graphene oxide substrate (O-CoGa/NG) and deliver outstanding nitrate reduction reaction (NO3RR) performance, making them excellent catalysts to construct highly efficient rechargeable Zn-NO3 - battery. Operando studies and theoretical simulations demonstrate that the electron-rich environments around the Co atoms enhance the adsorption strength of *NO3 intermediate and simultaneously suppress the formation of hydrogen, thus improving the NO3RR activity and selectivity.

Metal Nanoparticles for Simultaneous Use in AC Magnetic Field Hyperthermia and Magnetic Resonance Imaging.

Magnetic nanoparticles (MNPs) are produced for both diagnosis and treatment due to their simultaneous availability in magnetic resonance imaging (MRI) and magnetic hyperthermia (MHT). Extensive investigations focus on developing MNPs for individual MHT or MRI applications, but the development of MNPs for theragnostic applications has received very little attention. In this study, through efficient examination of synthesis conditions such as metal precursors, reaction parameters, and solvent choices, we aimed to optimize MNP production for effective utilization for MHT and MRI simultaneously. MNPs were synthesized by thermal decomposition under 17 different conditions and deeply characterized by transmission electron microscopy (TEM), x-ray diffraction (XRD), and x-ray photoelectron spectroscopy (XPS). The heating efficiency of MNPs under an alternating current (AC) magnetic field was quantified, while MRI performance was evaluated through agar phantom experiments. Our findings highlight the crucial role of benzyl ether in metal ion reduction and size control. Metal-doped iron oxide MNPs displayed promise for MHT, whereas Mn-doped iron oxide MNPs exhibited enhanced MRI capabilities. Consequently, five engineered MNPs were considered potential candidates for further studies, demonstrating their dual ability in MRI and MHT.

Exploring deep eutectic solvents of methane sulfonic acid and choline chloride: Formation, properties, and metal solvent effectiveness

Methane sulfonic acid (MSA), a hydrogen bond donor (HBD), was combined with choline chloride (HBA) at varying molar ratios (1:1, 1:2 and 2:1) to explore the formation of deep eutectic solvents (DES). The resulting blends, at 1:1 and 2:1 ratio, remained liquid at ambient temperature. Among these combinations, the DES formed with a 1:1 molar ratio (MSA-ChCl) exhibited the highest decomposition temperature (166 °C) followed by MSA-ChCl (1:2) and MSA-ChCl (2:1). Alongside, the glass transition temperature of the DES also remained relatively unaffected by the molar ratio of its components. Notably, both density and viscosity were observed to be temperature dependent. To elucidate hydrogen bonding interactions between choline chloride and MSA, Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy were employed. The broadening and shifting of IR peaks illustrate the formation of intermolecular bonding between MSA and ChCl. Density Functional Theory (DFT) calculations were conducted to optimise molecular structures, analyse HOMO-LUMO levels, estimate electronegativity and ionization potential, and generate electrostatic potential surfaces of the DES. As per calculated Molecular Electrostatic Potential (MEP) by DFT of pure MSA and ChCl, SO of MSA has most electron deficient region and it has potential to interact with electron positive OH part of ChCl, which is also demonstrated by IR spectra. MSA-ChCl (2:1) displayed the most negative electron density and proved to be the most effective metal solvent among the DES formulations tested. Exceptional solubility of lithium in MSA-ChCl (2:1) was observed, exceeding 105 mg/L. Moreover, zinc, copper, cobalt, and iron also demonstrated good solubility in MSA-ChCl (2:1), ranging from 105 to 104 mg/L.

Copper-Catalyzed Oxidation of 5-Hydroxymethylfurfural to 2,5-Diformylfuran Assisted by TEMPOL in Liquid Sunlight Methanol.

2,5-diformylfuran (DFF) is a significant biomass-derived compound with diverse applications in novel furan-based materials, fragrances, fuel additives, and drug synthesis. A pivotal challenge in DFF synthesis was developing a method to produce DFF under mild conditions using sustainable feedstocks. In this study, an affordable 4-hydroxy-2,2,6,6-tetramethylpiperidine (TEMPOL)- assisted Cu(OAc)2 catalytic system for aerobic oxidation reaction of HMF to DFF in liquid sunlight methanol solvent was developed. The effects of parameters such as metal species, catalyst amount, solvent species, base structure, and reaction temperature were systematically investigated. The evolution of product distribution in the reaction solution at various times was monitored and analyzed using 1H-NMR spectroscopy. FT-IR and ESI-MS characterizations were employed to integrate experimental findings and elucidate the reaction mechanism. The highest DFF yield of 96 % and complete conversion of HMF were obtained. Furthermore, a total DFF yield of 68.6 % was achieved from fructose using a two-steps method, demonstrating the potential for scalable production. The establishment of this catalytic system presents a novel approach for the selective preparation of DFF from sustainable feedstock.

Tuning the Optical Absorption Edge of Vacancy-Ordered Double Perovskites through Metal Precursor and Solvent Selection.

Vacancy-ordered double perovskites with the formula A 2 MX 6 (where A is a +1 cation, M is a +4 metal, and X is a halide ion) offer improved ambient stability over other main-group halide AMX 3 perovskites and potentially reduced toxicity compared to those containing lead. These compounds are readily formed through a number of synthetic routes; however, the manner in which the synthetic route affects the resulting structure or optoelectronic properties has not been examined. Here, we investigate the role of distinct precursors and solvents in the formation of the indirect band gap vacancy-ordered double perovskite Cs2TeBr6. While Cs2TeBr6 can be synthesized from TeBr4 or TeO2, we find that synthesis from TeBr4 is more sensitive to solvent selection, requiring a polar solvent to enable the conversion of TeBr4. Synthesis from TeO2 proceeds in all of the organic solvents tested, provided that HBr is added to solubilize TeO2 and enable the formation of [TeBr6]2-. Furthermore, the choice of metal precursor and solvent impacts the product color and optical absorption edge, which we find arises from particle size effects. The emission energy remains unaffected, consistent with the idea that emission in these zero-dimensional structures arises from the isolated [TeBr6]2- octahedra, which undergo dynamic Jahn-Teller distortion rather than band-edge recombination. Our work highlights how even minor changes in synthetic procedures can lead to variability in metrics such as the absorption edge and emission lifetime and sheds light on how the optical properties of these semiconductors can be controlled for light-emitting applications.

Two-dimensional Cu2N–A high-performance anode material for ion batteries with excellent electrical conductivity and electrolyte wettability

Determining suitable anode materials is crucial in the advancement of lithium-ion and sodium-ion battery technologies. We propose that the two-dimensional (2D) material Cu2N holds promise as a viable anode candidate. The Cu2N monolayer exhibits a stable checkerboard lattice crystal structure, ensuring structural integrity. Its excellent metallic electronic structure facilitates efficient conductivity during battery operation. We have observed that Li/Na ions can chemically bond to Cu2N substrates via specific charge exchange mechanisms. Moreover, the Cu2N monolayer demonstrates favorable wettability and compatibility with common electrolytes used in lithium-ion and sodium-ion batteries, including solvent molecules and metal salts. Our findings indicate that the Li/Na storage capacity of the Cu2N monolayer reaches approximately 760/760 mAh/g, surpassing that of graphite anodes significantly. Notably, the Li/Na diffusion barrier on the Cu2N monolayer is merely 5/13 meV, lower than that of most other 2D anode materials. Our results underscore the potential of the Cu2N monolayer as an outstanding electrode material, offering high storage capacity, rapid charge/discharge rates, and favorable wettability with electrolytes.

Oxidative Upcycling of Polyethylene to Long Chain Diacid over Co-MCM-41 Catalyst.

Plastic pollution is an emerging global threat due to lack of effective methods for transforming waste plastics into useful resources. Here, we demonstrate a direct oxidative upcycling of polyethylene into high-value and high-volume saturated dicarboxylic acids in high carbon yield of 85.9 % in which the carbon yield of long chain dicarboxylic (C10-C20) acids can reach 58.9% over cobalt-doped MCM-41 molecular sieves, in the absence of any solvent or precious metal catalyst. The distribution of the dicarboxylic acids can be controllably adjusted from short-chain (C4-C10) to long-chain ones (C10-C20) through changing cobalt loading of MCM-41 under nanoconfinement. Highly and sparsely dispersed cobalt along with confined space of mesoporous structure enables complete degradation of polyethylene and high selectivity of dicarboxylic acid in mild condition. So far, this is the first report on highly selective one-step preparation of long chain dicarboxylic acids. The approach provides an attractive solution to tackle plastic pollution and a promising alternative route to long chain diacids.

Oxidative Upcycling of Polyethylene to Long Chain Diacid over Co‐MCM‐41 Catalyst

AbstractPlastic pollution is an emerging global threat due to lack of effective methods for transforming waste plastics into useful resources. Here, we demonstrate a direct oxidative upcycling of polyethylene into high‐value and high‐volume saturated dicarboxylic acids in high carbon yield of 85.9 % in which the carbon yield of long chain dicarboxylic (C10‐C20) acids can reach 58.9% over cobalt‐doped MCM‐41 molecular sieves, in the absence of any solvent or precious metal catalyst. The distribution of the dicarboxylic acids can be controllably adjusted from short‐chain (C4‐C10) to long‐chain ones (C10‐C20) through changing cobalt loading of MCM‐41 under nanoconfinement. Highly and sparsely dispersed cobalt along with confined space of mesoporous structure enables complete degradation of polyethylene and high selectivity of dicarboxylic acid in mild condition. So far, this is the first report on highly selective one‐step preparation of long chain dicarboxylic acids. The approach provides an attractive solution to tackle plastic pollution and a promising alternative route to long chain diacids.

Electrochemical Liquid‐Liquid‐Solid Growth of Ag‐In Crystals with Liquid Indium Alloy Electrodes

AbstractSynthesis of intermetallic crystals by electrodeposition of Ag from alkaline aqueous electrolytes containing AgCN onto liquid metal electrodes via an electrochemical liquid‐liquid‐solid (ec‐LLS) process has been performed. X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy were performed to identify crystalline products. Ec‐LLS experiments performed with pure liquid Hg and Ga electrodes resulted in the formation of polycrystalline Ag2Ga and Ag2Hg3. Experiments performed with In‐containing liquid metals preferentially yielded Ag9In4 and AgIn2 products with liquid Hg0.35In0.65 and Ga0.86In0.14, respectively. The product distribution with liquid Hg0.35In0.65 depended on the level of Ag supersaturation during the electrodeposition. A mechanism that accounts for the aforementioned observations is presented and discussed. This work described the formation of Ag−In intermetallic phases by the isothermal electroreduction of Ag into different liquid metal solvents via ec‐LLS. Electrodeposition of Ag into a pure Ga or pure Hg liquid metal pool yielded precisely the compounds predicted from isothermal cross‐sections of the respective binary phase diagrams. These compounds were not found when using liquid Hg or Ga containing appreciable In. The smaller enthalpy of formation for AgIn2 was consistent with its synthesis in Ga0.86In0.14. However, the observed product of Ag9In4 in Hg‐containing liquid metals could not be rationalized solely from thermodynamic factors. Instead, this observation was consistent with a kinetic pathway based on the lability of Hg‐metal bonds and nearly identical crystal structures of Ag9In4 and Ag2Hg3. Site exchange of Hg for In is consistent with our prior observations[23] of In exchange into Hg−Pd structures during Pd electrodeposition. This mechanism is not based on any direct role of electrochemistry other than aspects that dictate the operative supersaturation of the metal solute.

Transformations in phenylboronic acid at high pressures and temperatures

A recent report on obtaining the n-type conductivity in diamonds doped with boron–oxygen complexes in a metal solvent (X. Liu et al., PNAS 2019) stimulates interest in the synthesis of diamonds in heterohydrocarbon systems with oxygen and boron. The simultaneous effect of boron and oxygen heteroatoms on phase transitions in a hydrocarbon system is examined in phenylboronic acid C6H5B(OH)2 at pressures of 7–8.5 GPa and temperatures up to 1600 °C. At pressures of about 7 GPa and temperatures up to 1100 °C, the transformation of the precursor occurs through the stage of polymerization into a graphane-like phase with the subsequent formation of nanographite. Micro- and nanodiamonds are synthesized at 8.5 GPa and 1600 °C from the initial precursor and nanographite, which is a product of preliminary carbonization, respectively. Despite the presence of oxygen and boron in the growth system, the n-type conductivity in diamonds and nanographite is not detected. It is found that the degree of boron doping of diamond in hydrocarbon systems decreases in the presence of oxygen with a high chemical affinity to boron and that nanodiamonds in the carbonized product can be obtained when volatile components leave the system.

Synthesis, crystal structure and anticancer activity of 4‑chloro-2-methoxybenzoic acid transition metal complexes

Seven novel transition metal complexes were synthesized from a starting material of 4‑chloro-2-methoxybenzoic acid, I: [Cu(4-Cl-2-MOBA)2(Py)2(H2O)2]; II: [Cu(4-Cl-2-MOBA)2(Imz)2]; III: [Co(4-Cl-2-MOBA)2(H2O)3.5]; IV: [Ni(4-Cl-2-MOBA)2(H2O)6]; V: [Ni(4-Cl-2-MOBA)2(DMF)]; VI: [Ni(4-Cl-2-MOBA)2(3-NH2–5-hypy)2(H2O)2O3.67] and VII: [Zn2(4-Cl-2-MOBA)3(4,4′-bipy)(Py)(HAc)]n by a one-pot, solvothermal method. All complexes were characterized by elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV–Vis), electrospray ionization mass spectrometry (ESI-MS) and single-crystal X-ray diffraction analysis (XRD). Single crystal XRD analyses showed that central metal ion type, auxiliary ligands and solvents acted synergistically to determine structural diversity. Complexes I-VII had cytotoxic activity towards the human tumor cell lines, A549 and SMMC-7721. Complex I showed the most potent cytotoxicity with an IC50 value of 8.976 μM for lung cancer cells and 13.94 μM for liver cancer cells.

Electrospun nanofiber composite based on bimetallic metal–organic framework/halloysite nanotubes/deep eutectic solvents/molecularly imprinted polymers for thin film microextraction of sulfonamides in milk, eggs and chicken meat by HPLC analysis

Herein, electrospun nanofibers based on bimetallic metal–organic framework@ functionalized halloysite/deep eutectic solvents/molecularly imprinted polymers was synthesized as new solid phase extractant for thin film microextraction of sulfacetamide, sulfamethoxazole, sulfamethazine and silversulfadiazine by HPLC-UV analysis. After synthesizing new phase through electrospinning nanofibers and thin film fabrication, we effectively leverage the synergistic properties of these materials within the composite structure. The resultant thin film nanocomposite, which integrates molecularly imprinted nanofibers, highlights the presence of inorganic nanotubes called halloysite, functionalized with a deep eutectic solvent and bimetallic metal–organic frameworks. Characterization of synthesized thin films were successfully characterized for structural, morphological, and surface analysis using infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). In this study, a syringe design was employed for the microextraction of sulfonamides (SAs) using thin film microextraction, which is carried out in two stages: adsorption and desorption, both within the syringe. The effects of several experimental conditions on desorption stage, including desorption parameters including pH, desorption solvent type, and ultrasonication time were studied by the single factor at a time. A Box-Behnken design (BBD) was applied to optimize the significant variables to obtain the optimum extraction conditions. The detection limit of the method was 0.003 µg/L and also the limit of quantification method was in the range of 0.01 µg/L. These results demonstrate the presented thin film microextraction method can serve as a good candidate for the microextraction and determination of sulfonamides in food samples like milk, eggs and chicken meat.

Metal and solvent dependent formation of imidazolidine or hemiaminal ether complexes

The coordination chemistry of the imidazolidinylpyridine ligand with Ni(II), Cu(II), Cd(II), and Zn(II) ions was investigated in both protic and aprotic solvents. Interestingly, the coordination environment around the metal center varied significantly depending upon the nature of metal ion and solvent used for synthesis. In acetonitrile the imidazolidinylpyridine bound to Cu(II) and Ni(II) remains intact, while in methanol it formed ring-opened hemiaminal ether. The Cd(II) and Zn(II) ion stabilized the imidazolidinylpyridine as a face-capping tridentate ligand regardless of the nature of the solvent. The imidazolidinylpyridine and the complexes formed were characterized by NMR spectroscopy, high resolution electrospray ionization mass spectrometry and single-crystal X-ray crystallography, appropriately. The structural features in the solid-state structures were particularly intriguing, shedding light on the complex interplay between the ligand, metal ions, and solvent environments in coordination chemistry.

Structural Evolution of Liquid Metals and Alloys.

Low-melting liquid metals are emerging as a new group of highly functional solvents due to their capability to dissolve and alloy various metals in their elemental state to form solutions as well as colloidal systems. Furthermore, these liquid metals can facilitate and catalyze multiple unique chemical reactions. Despite the intriguing science behind liquid metals and alloys, very little is known about their fundamental structures in the nanometric regime. To bridge this gap, this work employs small angle neutron scattering and molecular dynamics simulations, revealing that the most commonly used liquid metal solvents, EGaIn and Galinstan, are surprisingly structured with the formation of clusters ranging from 157to 15.7Å. Conversely, noneutectic liquid metal alloys of GaSn or GaIn at low solute concentrations of 1, 2, and 5 wt%, as well as pure Ga, do not exhibit these structures. Importantly, the eutectic alloys retain their structure even at elevated temperatures of 60 and 90°C, highlighting that they are not just simple homogeneous fluids consisting of individual atoms. Understanding the complex soft structure of liquid alloys will assist in comprehending complex phenomena occurring within these fluids and contribute to deriving reaction mechanisms in the realm of synthesis and liquid metal-based catalysis.

Purification and characterization of glutamate dehydrogenase from rainbow trout (Oncorhynchus mykiss) liver and molecular docking studies.

Glutamate dehydrogenase (GDH) participates in the energy metabolism of proteins and the synthesis of metabolites important for the organism. In this study, GDH enzyme was purified from the liver of rainbow trout (Oncorhynchus mykiss) by 2',5'-ADP Sepharose 4B affinity chromatography in one step. As a result of this purification process, GDH enzyme was purified 171-fold with 5.83U/mg protein-specific activity. The characterization experiments presented that the storage stability of the purified GDH enzyme was determined as -80°C; optimum temperature 40°C; it was determined that the optimum ionic strength was 100mM phosphate buffer and the optimum pH was 8.00. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and PAGE studies showed that the natural molar mass of the purified GDH enzyme was 346.74kDa, and the molar mass of its subunits was 53.71kDa. Km and Vmax values for substrates and coenzymes of GDH enzyme purified from rainbow trout liver were calculated, and the lowest Km value was found in NAD+ (1.86mM) and the highest Vmax value in NH4 + (1.79U/mL). The effects of some metal ions, vitamins, and solvents on the activity of the purified GDH enzyme were investigated and also IC50 values and inhibition types. The metal ion with the lowest IC50 value is Ag+ (8.65 ± 1.68μM), and the vitamin is B6 (0.77 ± 0.04mM). The binding affinities of inhibitors were investigated with molecular docking, based on the conformational state of GDH.

Carbonic Anhydrases: Different Active Sites, Same Metal Selectivity Rules.

Carbonic anhydrases are mononuclear metalloenzymes catalyzing the reversible hydration of carbon dioxide in organisms belonging to all three domains of life. Although the mechanism of the catalytic reaction is similar, different families of carbonic anhydrases do not have a common ancestor nor do they exhibit significant resemblance in the amino acid sequence or the structure and composition of the metal-binding sites. Little is known about the physical principles determining the metal affinity and selectivity of the catalytic centers, and how well the native metal is protected from being dislodged by other metal species from the local environment. Here, we endeavor to shed light on these issues by studying (via a combination of density functional theory calculations and polarizable continuum model computations) the thermodynamic outcome of the competition between the native metal cation and its noncognate competitor in various metal-binding sites. Typical representatives of the competing cations from the cellular environments of the respective classes of carbonic anhydrases are considered. The calculations reveal how the Gibbs energy of the metal competition changes when varying the metal type, structure, composition, and solvent exposure of the active center. Physical principles governing metal competition in different carbonic anhydrase metal-binding sites are delineated.

Breathable Iron-Based MIL-88 Framework as Dye Adsorbent in Aqueous Solution

Metal–organic frameworks (MOFs) have been observed to exclusively eliminate dyes confined within their respective pores. In this investigation, the synthesis of a breathable MOF structure, MIL-88B(Fe), was pursued with the objective of circumventing restrictions on pore size to enhance its adsorption capabilities. The synthesis of MIL-88B(Fe) was carried out via the assisted solvothermal method at 373 K using inexpensive yet environmentally benign FeCl3·6H2O, 1,4-benzenedicarboxylic acid, and DMF as a metal precursor, linker, and solvent, respectively. Furthermore, the MOF was subjected to extensive analytical characterisation using XRD, FT-IR spectroscopy, N2 gas sorption, TGA, and SEM. The experimental data showed that the utilisation of MIL-88B(Fe) with a dose level of 5 mg for 180 min at a pH of 9 led to the highest levels of adsorption for both dyes, with 162.82 mg g−1 for methylene blue (MB) and 144.65 mg g−1 for rhodamine B (RhB), as a result of the contrast in the molecular size between each dye. The Langmuir and Freundlich models demonstrated a correlation with isotherms, while the thermodynamic analysis demonstrated that MIL-88B(Fe) exhibits distinct endothermic and breathable properties. The efficacy of MIL-88B(Fe) adsorbent for MB and RhB in aqueous solutions indicated exceptional performance, stability, and noteworthy reusability performance.

Process intensification of metal solvent extraction studies using a miniaturized solvent extraction plant

This study examines the potential of a miniaturized solvent extraction plant (MSXP) to improve the efficiency and reproducibility of laboratory and pilot-scale metallurgical studies that typically require extended testing periods. The MSXP has been designed to replace conventional solvent extraction (SX) apparatus and aims to reduce start-up time, time to reach equilibrium, and overall test time. Two copper solvent extraction (Cu-SX) research campaigns were conducted to test the functionality, ease of operation, modularity, and reproducibility of the MSXP. The first campaign quantified the extraction efficiency and net copper transfer, while the second campaign operated the MSXP in a semicontinuous countercurrent flow configuration with three extraction and two stripping stages. The main variables studied in the first campaign are the number of stages (1-3), volumetric flow rates (O/A, 1-3), and organic phase residence time in the micro-contactor (0.7-2.4 min). The results demonstrate that the MSXP can work with very low stage efficiencies (48%), while achieving high copper recoveries (> 90%). At the stripping circuit level, we show that the MSXP can operate at superior stage efficiencies (> 100%), with low copper recoveries (30%–55%). The reproducibility evaluation also demonstrates high statistical confidence (< 6% CV) in the obtained process values. The MSXP offers great flexibility in net copper transfer and can be used to benchmark and emulate a wide range of Cu-SX systems. Experimental Cu-SX campaigns can be run in about 60 min while investing roughly US$1.4/h on reagents, which is significantly lower compared to typical campaigns that can last from days to weeks to reach reliable research outcomes and require about US$62/h for reagents. The potential of MSXP extends to more elaborate solvent extraction systems, specifically those designed to purify energy-critical elements like lithium, nickel, cobalt, or rare-earth elements. This study demonstrates the promise of process intensification approaches for improving the efficiency of laboratory and pilot-scale SX studies, which can help in reducing time, reagents, and energy consumption while improving the reproducibility of results.