Solubility Of Chloride Research Articles

Phase diagram of the eutectic type LiCl-PrCl3-KCl system with wedging liquidus of binary compound

Based on the published experimental data (phase diagrams of three binary systems, four isothermal sections and DTA curves of 33 alloys), a spatial (three-dimensional – 3D) computer model of the LiCl-PrCl3-KCl phase diagram has been constructed. It is shown that, in the general case, the diagram is formed by 66 surfaces and 27 phase regions; however, due to the negligible solubility of the initial chlorides and the stoichiometry of the two binary compounds in reality, it consists of 31 surfaces and 14 phase regions. The evaluation of the quality of the obtained 3D model is a comparison of model and initial isothermal sections and calculation of response functions for 33 alloys with temperature values at the boundaries of the primary crystallization regions shown on DTA traces. The geometric structure of the LiCl-PrCl3-KCl phase diagram is also considered as an illustration of the features of ternary systems of the eutectic type, depending on the nature of the formed in them binary compounds.

Performance evaluation of advanced machine learning methodologies in simulating hydrogen chloride (HCl) absorption by deep eutectic solvents

This work aims to construct the physical-based machine learning (ML) approach for estimating the hydrogen chloride (HCl) solubility in eleven different deep eutectic solvents (DESs). All DES-HCl equilibrium records versus temperatures and pressures are gathered from the literature to ensure ML universality. Then, a well-known feature selection technique was applied to identify the physically meaningful descriptors for the hydrogen bond acceptors (HBA) and hydrogen bond donors (HBD). Afterward, temperature, pressure, selected meaningful physical descriptors, and HBA/HBD molar concentrations are utilized to design ML tools to compute HCl solubility in DESs. Diverse MLs, including extreme learning machines, convolutional neural networks, long short-term memory, cascade neural networks, and extreme gradient boosting (XGBoost), are tested, and their accuracy is compared to select the best candidate. The XGBoost model predictions for HCl solubility in DESs are in acceptable agreement with the literature records. This model precisely simulates 417 DES-HCl equilibrium records in the temperature range of 293–348 K and pressures of up to 127 kPa with a correlation coefficient of 0.99621, mean absolute percentage deviation of 3.04, mean absolute error of 0.448, and root mean square error of 0.729. Results of the designed XGBoost model prove that acetamide-ethylene glycol (1:1), which can averagely dissolve up to 32.47 wt% (weight percent) of HCl, is the best DES for the HCl capture and recovery. After approving the XGBoost model reliability with different visual and numerical inspections, the Leverage method also justified its validity domain by more than 97.6%.

Thermodynamics of NaCl in dense water vapor via cross virial coefficients

Sodium chloride in the fluid phase is important for the chemistry of natural hydrothermal processes in the Earth’s crust and derived industrial utilizations, where thermodynamics is an essential part that can also to some extent fill in missing experimental data. The solubility of sodium chloride in crystalline form (halite) in water vapor is modeled using a novel combination of an accurate equation of state for pure water and a truncated virial equation for water mixed with sodium chloride. In the resulting Helmholtz energy expression, interactions between H2O and NaCl are incorporated through the second (B12), third (C112), and fourth (D1112) cross virial coefficients. The temperature dependence of the coefficients has been determined by regression to experimental data. Specifically, the temperature dependence of B12 is assumed to follow that of a square-well gas, whereas C112 and D1112 are calculated using purely exponential functions of inverse temperature. The temperature dependence of B12 is supported by independent calculations of ab initio interaction energies between H2O and NaCl. For water itself, all terms in the virial equation are collectively modeled by the IAPWS-95 equation of state. For sodium chloride, interactions between two or more NaCl molecules are disregarded. The model shows quantitative agreement with available solubility data in the vapor–halite coexistence region, which implies that the water vapor density is approximately less than 130kgm−3. Its theoretical basis ensures that predictions are reliable in regions where experimental data are missing. The direct calculation of cross virial coefficients is overall useful for modeling geochemical fluids with low solute concentrations, including systems with multiple solvents.

Brønsted-Lowry Acid-Based Aqueous Eutectic Electrolyte for Practical Zinc Batteries.

Aqueous highly concentrated electrolytes (AHCEs) have recently emerged as an innovative strategy to enhance the cycling stability of aqueous Zinc (Zn) batteries (AZB). Particularly, thanks to high Zn Chloride (ZnCl2) solubility in water, AHCEs based on ZnCl2 feature remarkable Zn anode stability. However, due to their inherently acidic pH and Cl- anion reactivity, these electrolytes face compatibility challenges with other battery components. Here, an aqueous eutectic electrolyte (AEE) based on Brønsted-Lowry concept is reported-allowing the usage of cheap and abundant salts, ZnCl2, and sodium acetate (NaAc). The reported, pH buffered, AEE displays a higher coordination of water at an even lower salt concentration, by simply balancing the acceptor-donor H─bonding. This results in impressive improvement of electrolyte properties such as high electrochemical stability, high transport properties and low glass transition temperature. The developed AEE displays higher compatibility with vanadium oxide-based cathode with a 50% increase in capacity retention in comparison to sat. ZnCl2. More importantly, the pH buffered AEE solves the incompatibility issues of ZnCl2 toward commonly used aluminium (Al) current collector as well as cellulose separator. This work presents an efficient, simple, and low-cost strategy for the development of aqueous electrolytes for the practical application of Zn batteries.

A streamlined molecular-dynamics workflow for computing solubilities of molecular and ionic crystals.

Computing the solubility of crystals in a solvent using atomistic simulations is notoriously challenging due to the complexities and convergence issues associated with free-energy methods, as well as the slow equilibration in direct-coexistence simulations. This paper introduces a molecular-dynamics workflow that simplifies and robustly computes the solubility of molecular or ionic crystals. This method is considerably more straightforward than the state-of-the-art, as we have streamlined and optimised each step of the process. Specifically, we calculate the chemical potential of the crystal using the gas-phase molecule as a reference state, and employ the S0 method to determine the concentration dependence of the chemical potential of the solute. We use this workflow to predict the solubilities of sodium chloride in water, urea polymorphs in water, and paracetamol polymorphs in both water and ethanol. Our findings indicate that the predicted solubility is sensitive to the chosen potential energy surface. Furthermore, we note that the harmonic approximation often fails for both molecular crystals and gas molecules at or above room temperature, and that the assumption of an ideal solution becomes less valid for highly soluble substances.

CoCl2·6H2O crystal growth and its spectral characteristics

For the first time, a crystal of cobalt (II) chloride hexahydrate has been obtained, the size and quality of which have made it possible to study its faceting and spectral characteristics. The temperature dependence of the cobalt chloride solubility has been determined in the temperature range 29–44 °C. The temperature range of the transition area of change in the composition of equilibrium crystalline hydrates of cobalt chloride from CoCl2·6H2O to CoCl2·2H2O has been established. A CoCl2·6H2O crystal has been grown from a water solution, and its main transmission bands in the wavelength range of λ = 200–1400 nm and thermal stability have been estimated.

Density, Viscosity, and CO2 Solubility of a Deep Eutectic Solvent Comprising Choline Chloride and Ethylene Glycol

Density, Viscosity, and CO₂ Solubility of a Deep Eutectic Solvent Comprising Choline Chloride and Ethylene Glycol

Correction of the 3D Computer Model of the Phase Diagram for the LiCl–PrCl3–KCl System Using Thermoanalytical Curves

A spatial (3D) computer model of an isobaric phase diagram of the LiCl–PrCl3–KCl system was designed. The model was assembled of 66 surfaces and 27 phase regions, of which 31 surfaces and 14 phase regions degenerate to verticals or vertical planes because of the limited solubilities of the initial chlorides and their compounds. Published experimental isothermal sections and thermoanalytical curves for 33 salt melts were used to improve the quality of the 3D model. The results can be used to improve the molten-salt refining technology of nuclear fuel waste.

Postdeposition Halide Exchange for Achieving Deep-Blue Perovskite Light-Emitting Diodes: The Role of the Organic Cations in the Chloride Source.

Postdeposition halide exchange has been a popular strategy for tuning the emission wavelength of metal halide perovskites and is particularly attractive in achieving deep-blue perovskite light-emitting diodes (PeLEDs), where the quality of the emissive layer is largely limited by the low solubility of chlorides in perovskite precursor solution. In this work, the halide exchange strategy isexamined for deep-blue PeLEDs, with a focus on understanding the role of the organic cations of the halide salt (i.e., the chloride source for ion exchange) in modifying the properties of the perovskite films and consequently the PeLED performances. By comparatively investigating the treatment effects of two model systems, namely phenethylammonium chloride and 2,2-diphenylethylammonium chloride (DPEACl), it isfound that although the two chlorides produce highly similar photoluminescence properties of the perovskite films, they create different landscapes for current flow in the PeLEDs. In particular, the bulky branch-structured DPEA cations exhibit minimal disturbance to the perovskite grains while providing highly effective inter-grain void filling and thus leakage current blocking, leading to 3D perovskite-based PeLEDs with a record high peak external quantum efficiency of 6.4% at 462nm. The study highlights the importance of organic cation selection in the halide exchange processes for PeLEDs.

Exploring detailed microcosmic mechanisms of sodium chloride deposition in supercritical water reactors from the aspect of solvation structure: A combination of MD and QM simulations

The dissolution characteristics and microscopic dissolution process of salt in supercritical water (SCW) are the fundamental influence of scale formation. In this paper, molecular dynamics (MD) and quantum mechanics (QM) were used to study the solubility and solvation structure of sodium chloride in supercritical water. The potential mean force (PMF), radial distribution function (RDF) and coordination number (CN) indicate that the solubility of sodium chloride in SCW decreases with the increase of temperature and the decrease of density. As the system density decreases from 0.3 g/cm3 to 0.1 g/cm3 and the temperature increases from 600 K to 900 K, the CN of water molecules in the solvation shell decreases from 2.89 to 1.01, which is consistent with the trend of the experimental results. The electrostatic potential distribution and intermolecular interaction of the solvation shell around Na+ were obtained by QM method. The solution free energy of Na+–3H2O in implicit solvent was obtained. In the condition range of this study, when the temperature is the lowest and the dielectric constant is the largest, the free energy of dissolution is the smallest, which is −0.0991 a.u. This study will lay a foundation for the study of salt deposition in SCW.

Influences of MW on cement mortar properties at different magnetic exposure

The field of civil engineering continues to promote the use of high-performance materials and environmentally friendly construction methods. On the other hand, water is essential to the functionality of concrete. Water needs to be salt-free and have qualities that are on par with potable water in order to prevent corrosion and add strength to concrete. When combined and cured with magnetic water, cement mortar specimens were tested at various exposure intervals, including instant, 15 min, 30 min, 45 min, and 60 min. In this method, water is passed through a magnetic field, which causes the water molecules to rearrange themselves inside the structure. This enhances percolation of the water within the cementitious particles and speeds up and improves the hydration process. This research investigates the efficient usage of magnetic water in the preparation of cement mortar specimens over normal water under different exposure times. The outcome of magnetized water (MW) with an increase in exposure in cement mortar has been obtained as a better operative one and less porous over normal water mix. The air content in the fresh mortar will be reduced up to 17.67 % using MW mixing after 60 min of exposure time. According to the experimental findings, a magnetic water mix increased the compressive strength by 16.68 % over the course of 28 days with only 60 min of exposure. Utilizing magnetic water decreases the porosity rate and the solubility of chloride in fresh cement mortar without affecting the parameters governing strength.

A novel protocol to recycle zirconium from zirconium alloy cladding from used nuclear fuel rods

A potential new zirconium recycling protocol has been demonstrated using unirradiated Zircaloy-based claddings and depleted uranium oxide for the chemical removal of zirconium alloy cladding in used nuclear fuel (UNF) rods from light water reactors. This protocol is based on the application of three new scientific findings. First, a new lower temperature chlorination reaction of zirconium with sulfur monochloride is described. Second, the high solubility of zirconium chloride in thionyl chloride is used to separate it from uranium oxide fuel and fission and activation contaminants. Finally, in the third step, the zirconium chloride is purified by simple recrystallization from thionyl chloride. Utilizing sulfur chloride solvents for a lower temperature liquid-based chemical digestion and purification of zirconium alloy claddings reduces technical complications experienced by current high temperature gas phase chlorination strategies, such as contamination of product streams. This novel protocol has been demonstrated on a 3–50 g scale of unirradiated zirconium alloy, with no significant change in the time required for complete chlorination (3–4 h). This zirconium chlorination protocol has also been performed in the presence of depleted uranium oxide pellets. The depleted fuel pellets do not affect zirconium chlorination, and the chlorination protocol does not chemically or physically alter the fuel pellets. A preliminary description of an industrial protocol to recycle nuclear grade zirconium from UNF rods is presented.

Identification of Nano-Metal Oxides That Can Be Synthesized by Precipitation-Calcination Method Reacting Their Chloride Solutions with NaOH Solution and Their Application for Carbon Dioxide Capture from Air-A Thermodynamic Analysis.

Several metal oxide nanoparticles (NPs) were already obtained by mixing NaOH solution with chloride solution of the corresponding metal to form metal hydroxide or oxide precipitates and wash-dry-calcine the latter. However, the complete list of metal oxide NPs is missing with which this technology works well. The aim of this study was to fill this knowledge gap and to provide a full list of possible metals for which this technology probably works well. Our methodology was chemical thermodynamics, analyzing solubilities of metal chlorides, metal oxides and metal hydroxides in water and also standard molar Gibbs energy changes accompanying the following: (i) the reaction between metal chlorides and NaOH; (ii) the dissociation reaction of metal hydroxides into metal oxide and water vapor and (iii) the reaction between metal oxides and gaseous carbon dioxide to form metal carbonates. The major result of this paper is that the following metal-oxide NPs can be produced by the above technology from the corresponding metal chlorides: Al2O3, BeO, CaO, CdO, CoO, CuO, FeO, Fe2O3, In2O3, La2O3, MgO, MnO, Nd2O3, NiO, Pr2O3, Sb2O3, Sm2O3, SnO, Y2O3 and ZnO. From the analysis of the literature, the following nine nano-oxides have been already obtained experimentally with this technology: CaO, CdO, Co3O4, CuO, Fe2O3, NiO, MgO, SnO2 and ZnO (note: Co3O4 and SnO2 were obtained under oxidizing conditions during calcination in air). Thus, it is predicted here that the following nano-oxides can be potentially synthesized with this technology in the future: Al2O3, BeO, In2O3, La2O3, MnO, Nd2O3, Pr2O3, Sb2O3, Sm2O3 and Y2O3. The secondary result is that among the above 20 nano-oxides, the following five nano-oxides are able to capture carbon dioxide from air at least down to 42 ppm residual CO2-content, i.e., decreasing the current level of 420 ppm of CO2 in the Earth's atmosphere at least tenfold: CaO, MnO, MgO, CdO, CoO. The tertiary result is that by mixing the AuCl3 solution with NaOH solution, Au nano-particles will precipitate without forming Au-oxide NPs. The results are significant for the synthesis of metal nano-oxide particles and for capturing carbon dioxide from air.

In Situ Halide Exchange of Cesium Lead Halide Perovskites for Blue Light-Emitting Diodes.

3D perovskites are promising to achieve efficient and bright deep-blue light-emitting diodes (LEDs), which are required for lighting and display applications. However, the efficiency of deep-blue 3D perovskite-based LEDs is limited by high density of defects in perovskites, and their deep-blue emission is not easy to achieve due to the halide phase separation and low solubility of chloride in precursor solutions. Here, an in situ halide exchange method is developed to achieve deep-blue 3D perovskites by spin-coating an organic halide salts solution to treat blue 3D perovskites. It is revealed that the halide-exchange process is mainly determined by halide ion diffusion targeting a concentration equalization, which leads to homogeneous 3D mixed-halide perovskites. By further introducing multifunctional organic ammonium halide salts into the exchange solution to passivate defects, high-quality deep-blue perovskites with reduced trap density can be obtained. This approach leads to efficient deep-blue perovskite LEDs with a peak external quantum efficiency (EQE) of 4.6% and a luminance of 1680cdm-2 , which show color coordinates of (0.131, 0.055), very close to the Rec. 2020 blue standard. Moreover, the halide exchange method is bidirectional, and blue perovskite LEDs can be achieved with color coordinates of (0.095, 0.160), exhibiting a high EQE of 11.3%.

Recent advances in glycerol hydrochlorination: Impact of reaction temperature, hydrogen chloride solubility and reaction intermediates

A homogeneously catalyzed gas–liquid process, glycerol hydrochlorination was studied in a semibatch reactor with gaseous hydrogen chloride (HCl) as a continuous phase and acetic acid as homogeneous catalyst. Several experiments were conducted varying the temperature in the jacket of the reactor in the range 70–115 °C and the catalyst mole fraction between 0 and 15 mol-%. The effects of HCl on the kinetics was investigated by changing the partial pressure of HCl in the range 0.25–1 atm by diluting HCl with inert gas, while the absolute pressure of the reactor was remained constant at atmospheric pressure. The experiments revealed new information about this particular reaction system. Considerable changes in the reactor temperature occurs, temperature changes close to 20 °C, which are an effect of the absorption process of gaseous HCl. The HCl uptake in the liquid phase exhibits a strange behavior at the beginning of the reaction, associated to the appearance of water and the temperature change during the experiments. The experiments also revealed that a part of the catalyst is transformed into esters in the presence of glycerol and 3-chloro-1,2-propanediol (α-MCP), particularly at high catalyst concentrations. These esters were detected and an improved gas-chromatographic method was developed to analyze these quantitatively. In long run, the esters are converted back to the original catalyst, acetic acid, as the reaction stops because of lack of glycerol. The information provided by the experiments in this work gives better understanding of the reaction mechanism and thus they are the basis for a rational design of glycerol hydrochlorination reactors.

Metal ions immobilized on polymer ionic liquid as novel efficient and facile recycled catalyst for glycolysis of PET

Environmental pollution aroused by accumulation of waste PET has attracted worldwide attention. Metal chloride as Lewis acid catalyst has excellent catalytic performance in enormous organic reaction. However, the high solubility of the metal chloride in ethylene glycol and the residue of metal ions in the product will have an adverse impact on the subsequent process. In this work, polymer ionic liquid containing [NTf2]− which is insoluble in ethylene glycol at room temperature was synthesized and used to immobilize metal ions to catalyze glycolysis of PET. After reaction, the polymer ionic liquid-metal ion catalyst could be recovered at room temperature by simple filtration. PET conversion reached 95.4% and BHET yield reached 77.8% using PIL-Zn2+ as catalyst at 195 °C for 120 min. Ionic liquid was characterized by FT-IR, NMR and ESI-MS. Interaction between ionic liquid and metal ions was characterized by FT-IR. The interaction energy of polymer ionic liquid-metal ion complex is higher than that of ethylene glycol-metal ion complex by DFT calculation (Density functional calculation). The both content of metal ion in polymer ionic liquid-metal ion complex and catalytic performance of as-synthesized catalysts did not obviously decrease after the catalyst was reused for five times. This work mainly provided a way of recovering catalyst and promote development of glycolysis of PET.

In-situ anodic precipitation process for highly efficient separation of aluminum alloys

Electrorefining process has been widely used to separate and purify metals, but it is limited by deposition potential of the metal itself. Here we report in-situ anodic precipitation (IAP), a modified electrorefining process, to purify aluminium from contaminants that are more reactive. During IAP, the target metals that are more cathodic than aluminium are oxidized at the anode and forced to precipitate out in a low oxidation state. This strategy is fundamentally based on different solubilities of target metal chlorides in the NaAlCl4 molten salt rather than deposition potential of metals. The results suggest that IAP is able to efficiently and simply separate components of aluminum alloys with fast kinetics and high recovery yields, and it is also a valuable synthetic approach for metal chlorides in low oxidation states.

Effect of The Number of Hydroxyls and Carbons on the Solubility of Sodium Chloride in Alcohol and The Electropolishing Behavior of Ti-6Al-4V Alloy in Alcohol-Salt System

Ethylene glycol-sodium chloride (NaCl) is an environmentally friendly electrolyte in the electropolishing of titanium. To better understand the effect of the alcohol on the electropolishing of titanium, the solubility of NaCl in different alcohols and the electropolishing of titanium with different mixtures have been systematically investigated. The results reveal that the solubility of NaCl increases with the increase of hydroxyls (-OH), but decreases with the increase of carbons (C) in alkyl (-R). Moreover, the conductivity of the electrolyte increases both as the increasing of NaCl concentration and temperature, and methanol, 1,2-propanediol, and glycerol-NaCl electrolytes could be also selected as candidates for further electropolishing titanium group metals.

An experimental study of the solubility of rare earth chloride salts (La, Nd, Er) in HCl bearing water vapor from 350 to 425 °C

The solubilities of the rare earth chlorides REECl3, where REE = (La, Nd, Er), were measured in HCl bearing water vapor from 350 to 425 °C with water partial pressures ranging from 8 to 170 bar. Solubility data were fit to the Pitzer-Pabalan quasi-chemical model in order to extract thermodynamic parameters for the formation of the gaseous REE-chloride-water clusters REECl3(H2O)n. The data show that the solubility of the REE chlorides are orders of magnitude higher than salts such as NaCl or CuCl at low water fugacities, despite their sublimation energies being substantially higher. This enhanced solubility is likely due to the high enthalpy associated with binding a single water molecule to form the species REECl3(H2O), with derived enthalpies ranging from −378 to −465 kJ/mol. Addition of further water molecules to form higher order clusters (n > 1) involves enthalpy changes of ~−20 kJ/mol, and are in effect thermodynamically suppressed over the temperature range 350–425 °C. Despite the enhanced solubility of small REECl3 water clusters, simulations of boiling processes demonstrate that the REE show highly conservative behavior, partitioning strongly into the dense aqueous phase. Not surprisingly, the presence of phosphates in the system makes this effect even more pronounced, completely immobilizing the REE. This would reduce transport in both the vapor and aqueous phase to negligible levels. However, we suggest that vapor phase transport of the REE may play a significant role in systems having a relatively low partial pressure of water (below the saturation point), where the relatively high stability of the first hydrated REE chloride clusters (REECl3(H2O) and REECl3(H2O)2) will give a preference for gas transport of the REE relative to other elements. This can likely happen in systems involving a gas/melt exchange in fumarolic exhalations, where water vapor discharges at relatively low (close to atmospheric) pressures.

Tunable crystal structure of Cu2SnS3 deposited by spray pyrolysis and its impact on the chemistry and electronic structure

Cu2SnS3 (CTS) thin films were grown by spray pyrolysis using two synthetic routes: stoichiometric and substoichiometric in an aprotic media. The use of dimethyl sulfoxide (DMSO) as a solvent improved the solubility of metal chlorides at room temperature, which was crucial to avoid metal-hydroxylation. In this sense, a mechanism for the solvation of metal chloride precursors in an aprotic media is proposed. Different sulfurization temperatures allowed the presence of diverse crystalline structures of Cu2SnS3, corroborated by Raman Spectroscopy and X-ray diffraction. For the substoichiometric composition Cu/Sn = 1.76 and a temperature annealing interval of 350–600 °C, the films showed the monoclinic-Cu2SnS3 phase. While for the stoichiometric composition Cu/Sn = 2, the tetragonal-Cu2SnS3 phase was present between 300 and 400 °C. At 500 °C, the Cu content increase allows the orthorhombic-Cu3SnS4 phase formation. The presence of Sn4+ and Cu+ species was confirmed by X-ray photoelectron spectroscopy (XPS) measurements. Simultaneously, electronic structures of the surface of the film were obtained by XPS combined with inverse photoemission spectroscopy (IPES). Bandgap values were 1.33 eV, 1.25 eV, and 1.15 eV for those films with tetragonal, orthorhombic, and monoclinic phases. The proximity of the valence band maximum (VBM) to the Fermi level causes that these compounds have a p-type nature, producing a small cliff in the conduction band alignment at the CdS/CTS interface. Photoresponse measurements revealed that all the samples are photoconductive to be considered as an option for solar applications.