Mixture Of Cations Research Articles

Dimensionality Engineering and Spin-Splitting Enhancement in Heterostructured Perovskites Through Organic Cation Chirality.

Enhanced spin-splitting driven by inversion asymmetry can be effectively achieved through the incorporation of chiral organic cations in hybrid organic-inorganic systems. Herein, we investigated the mechanisms and implications of chirality transfer in heterostructured perovskites belonging to the (PbBr2)2A2PbBr4 family, where A represents the organic cation. These structures are characterized by an inorganic-organic-inorganic stacking configuration comprising one perovskite monolayer and one PbBr2 intergrowth domain. Our findings indicate that all heterostructures are likely to exhibit energetic stability. Importantly, the presence of chiral cations introduces local asymmetries that facilitate significant spin-splitting effects. Additionally, a racemic mixture of chiral cations can induce a transition from two-dimensional to zero-dimensional character within the perovskite domain of the heterostructure. The dimensionality transition observed for the racemic mixture of isomers within the structure is attributed to the effect of hydrogen bond asymmetries and the enhanced lattice strain, leading the 2D perovskite framework to disrupt into isolated octahedra that allow breaking of centrosymmetry, in stark contrast with racemic 2D perovskites previously reported in the literature. Consequently, we predict that the introduction of chiral cations into perovskite heterostructures can create stable systems where a single degree of freedom effectively modulates both spin-resolved properties and dimensionality. This discovery provides a vital design principle for the simultaneous tuning of spin splitting and perovskite dimensionality.

Antimicrobial Properties of Monomeric and Dimeric Catanionic Surfactant System.

Cationic gemini surfactants are used due to their broad spectrum of activity, especially surface, anticorrosive and antimicrobial properties. Mixtures of cationic and anionic surfactants are also increasingly described. In order to investigate the effect of anionic additive on antimicrobial activity, experimental studies were carried out to obtain MIC (minimal inhibitory concentration) against E. coli and S. aureus bacteria. Two gemini surfactants (12-6-12 and 12-O-12) and two single quaternary ammonium salts (DTAB and DDAC) were analyzed. The most commonly used commercial compounds of this class, i.e., SDS and SL, were used as anionic additives. In addition, computer quantum mechanical studies were also carried out to confirm the relationship between the structure of the mixture and the activity. The obtained results of microbiological tests and quantum mechanical calculations are in agreement with each other and show the lack of synergism in catanionic mixtures in the case of antibacterial activity.

Freshness monitoring of some food products using pH-responsive smart films containing cyanidin cation

In this study, we introduced an innovative method by incorporating 1-butyl-3-methylimidazolium chloride (BmimCl) as a versatile component and fine-tuning the mixture of chitosan, BmimCl, and cyanidin cation (Anth) to create pH-responsive smart films for food freshness. Owing to the dual functionality of BmimCl, it served as a plasticizer as well as enhanced the film's capacity to display a broader spectrum of visible color changes. The material properties of chitosan films containing BmimCl and Anth at varying concentrations were characterized using FTIR, XRD, mechanical test, TGA, UV–vis and pH sensitivity. The combined results indicate that the chitosan-based pH-responsive smart film possessed excellent mechanical properties, great thermal stability, high light transmission, and a broad pH sensitivity. pH-responsive films were used for real-time freshness monitoring of freshwater shrimps, sterilized milk, and hairtails. Results revealed that BmimCl disrupts the hydrogen bond network of chitosan molecules. The films exhibit a transition from green to red as the food turns from fresh to spoiled, effectively demonstrating their capability to monitor freshness.

Surface and Bulk Stabilization of Silicon Anodes Via in-Situ Formation of Li-M-Si Zintl Phases Using Multivalent Cation Additives

Silicon is drawing attention as the upcoming anode material for the next generation of lithium-ion batteries due to its higher capacity compared to commercial graphite. However, silicon anions formed during lithiation are highly reactive with binder and electrolyte components creating an unstable SEI layer and limiting the calendar life of silicon anodes. In this study, the reactivity of lithium silicide and the formation of unstable SEI layer is mitigated by utilizing the use of a mixture of Ca and Mg multivalent cations as an electrolyte additive for Si anodes to improve their calendar life. Ca and Mg ions in the electrolyte diffuse into silicon particles forming relatively thermodynamically stable quaternary Li-Ca-Mg-Si Zintl phases with less chemical reactivity, in an in-situ fashion, stabilizing the bulk. Ca and Mg cations also react with the F anions in the electrolyte, forming a layer of nanocrystalline CaF2 and MgF2 that is closely coated around the silicon particles. The CaF2-enabled new SEI is strong and dense, which effectively protects the silicon core from side reactions, leading to lower capacity decay after calendar aging at high voltage. To understand the mechanism of ternary/ quaternary Zintl phase formation and its dynamics upon lithiation/delithiation, high-resolution solid-state 7Li and 29Si nuclear magnetic resonance (NMR) are utilized to directly probe the local Li and Si environments on Si electrodes harvested from coin and pouch cells at various states of (de)lithiation. The effect of multivalent cation additives on bulk and surface of aged silicon anodes was studied by multiple structural characterization techniques such as Electron Microscopy, HRXRD, ex situ and operando solid-state NMR. The results show that the electrodes that are gone through cycling and calendar aging with multivalent cations tended to have less cracking on the electrode surface, less lithium trapping in the bulk and the presence of mixed cations enhances cation migration and formation of quaternary Zintl phases stabilizing bulk and forming a more stable SEI in comparison to baseline electrolytes.

Derivation of toxicity parameters from field data: Analysis of lake zooplankton species responses to metals and acidity

The WHAM-FTOXβ model describes the toxic effects of mixtures of protons and metal cations towards biological species, using a set of intrinsic parameters for the cations (αH, αM*) and a sensitivity parameter (β) for each species. We applied the model to extensive water chemistry and zooplankton species occurrence data for four lakes contaminated with acidity and metals (Al, Ni, Cu, Zn) at Sudbury, Ontario, over the period 1973-2018, during which cation contamination declined, and zooplankton species numbers increased. Assuming that the appearance of a species resulted solely from decreases in water toxicity, and that αH and αM* values previously derived from laboratory toxicity test data could be applied in the field, we used the field data to estimate values of β for individual lake zooplankton species. Results for lake-species pairs with 20 or more species occurrences (from six samplings per year) were analysed. In most cases, the number of occurrences increased over time from zero to five or six per year, then remained at the high level. For a minority of pairs, occurrences per year increased initially, but subsequently declined, and so data only from the initial period were used to estimate β. The β values derived for the lake zooplankton are reasonably consistent with values derived from laboratory data for a range of other species. The findings support the application of WHAM-FTOXβ to describe toxic effects of mixtures of cations in the field, and the toxicity model might be combined with ecological theory to interpret natural population responses.

Synergistic doping chemistry enable the cycling properties of single-crystal Ni-rich cathode for lithium-ion batteries

Nickel-rich cobalt-low layered oxides have attracted much attention as positive electrode materials for high-energy lithium-ion batteries due to their high capacity and low cost, but their inherent stress accumulation and severe cationic mixed reactions will deteriorate the cycling performance. Herein, the nickel-rich single-crystalline LiNi0.90Co0.06Mn0.04O2 cathode material doped with W and Mg (NCM-WM) has been fabricated to overcome its structure degradation issues. It can be found that the Li/Ni cation mixture can be suppressed by the introduction of Mg2+ into Li+ situs and the replacement of transition metal ions by W6+. Meanwhile, the co-doing strategy synergistically depresses the irreversible H2-H3 phase transition to weaken the internal stress, and employs the heteroatoms as the pillar ions to prevent layer structure collapse. In addition, the reduced particle size induced by the W6+ and increased free electron resulted by Mg2+ can cooperatively improve the migration kinetics of ions and electrons in the process of cycling. As expected, the above advanced effects result in the prominent cycling properties (capacity retention of 86.7 %, 150 cycles, 2C) of the designed Ni-rich electrode materials. These results demonstrate that the co-doped design is a greatly effective strategy to reinforce the cycling performance of Ni-rich single-crystalline materials.

Enabling the photochromism of 4′-aminoflavylium compounds in water by host-guest interaction with β-cyclodextrin

Aminoflavylium compounds are known to display poor photochemical properties in water precluding their application in aqueous medium. In this work, we show that the host-guest encapsulation with β-cyclodextrin (β-CD) significantly improves the photochemical performance of 4′-aminoflavylium enabling their operation in aqueous solution. The pH-dependent thermodynamics and kinetics of two aminoflavylium compounds 4’-(N,N-dimethylamino)-7-hydroxylflavylium (4′NMe27OH) and 4’-(N,N-diethylamino)-7-hydroxylflavylium (4′NEt27OH) were studied in water in the absence and presence of β-CD. The association constants follow the order trans-chalcone > quinoidal base > flavylium cation, resulting in β-CD lowering both pKa and pK'a. All species in the 4′NEt27OH multistate system interact more strongly than those in 4′NMe27OH. The pH-dependent kinetics toward the equilibrium follows a bell-shaped curve at moderately acidic pH and increases in the presence of β-CD in both compounds. At highly acidic pH, protonation of trans-chalcone accelerates the kinetics, particularly for 4′NEt27OH due to the easier protonation of the trans-chalcone. In the presence of β-CD this effect is reduced, because protonation of trans-chalcone becomes more difficult.Upon irradiation of trans-chalcone in both compounds in the presence of β-CD, the pale yellow trans-chalcones convert into a purple, less-bound mixture of the flavylium cation and quinoidal base, with a quantum yield of ∼0.01.

Size polydisperse model ionic liquid under confinement: A molecular dynamics study

The performance of an electric double-layer capacitor is strongly influenced by the choice of electrolyte, and the use of ionic liquid (IL) mixtures as an electrolyte has shown great promise. In this study, a model IL made of a mixture of anions and size-polydisperse cations in equal numbers and confined between two electrodes is investigated by means of molecular dynamics simulations. In particular, using the extent of size-polydispersity (characterized by polydispersity index, δ) as a control parameter, we systematically explore its effect on the local structure, charge profile, ion size distribution in the vicinity of electrode surfaces, and differential capacitance. It is observed that the charge density profiles near cathode, i.e., region comprising both Stern and diffused layers, are significantly affected under the variation of δ in addition to the electrode charge density. Ion population, ordering of different-size cations, and its effective size in the vicinity of electrodes under neutral and applied potential conditions are also quantified. An interesting observation is that the effective cation size in the Stern layer decreases with increasing value of δ in the case of moderate to strong electrode surface charge density. This behaviour can be qualitatively understood from the interplay of enthalpic and entropic forces in the system. Finally, a non-monotomic dependence of capacitance on δ is observed with maximum value of capacitance at a rather small value of δ(≈3%) for the model system.

The aggregation structure and rheological properties of catanionic surfactant mixtures and potential applications in fracturing fluids

Clean fracturing fluids are widely used in reservoir stimulation and increasing production due to their characteristics of simple preparation, no residue, easy flowback, and low damage. At present, clean fracturing fluids are mainly prepared by cationic surfactants as main agent and inorganic or organic salts as additives, which can lead to unavoidable losses of cationic surfactants due to their adsorption in the formation. Anionic-cationic surfactants composite system can not only compensate for the shortcomings of a single surfactant system, but also improve the reservoir adaptability of the surfactant system. In this paper, a clean fracturing fluid was prepared with long-chain anionic surfactant, Sodium erucate (NaOEr), as main agent and a series of cationic surfactants with different as additive. Then, the aggregation behavior of mixed system was determined by visual appearance, rheology experiments, differential scanning calorimetry and cryogenic transmission electron microscopy. The phase transition mechanism induced by temperature was proposed, and the performance of the mixed system as a fracturing fluid was evaluated. The results showed the mixed systems could self-assemble into wormlike micelles when the length of hydrophobic carbon chains of cationic surfactant was 6 and 8. Increasing the length of the hydrophobic carbon chain could enhance the electrostatic effect, leading to precipitation in the mixed system. When the ratio of cationic surfactant was between 0.5 and 0.6 and the concentration was between 68 and 175 mmol∙L-1, the mixed systems tended to form three-dimensional structures by entangling and stacking wormlike micelles, showing high viscoelasticity and viscosity. The aggregation structure of the mixed system transformed from vesicles to wormlike micelles at 46.8 °C, which is attributed to the transition of carbon chains of NaOEr from non-flexible to flexible. Finally, the mixed system as a fracturing fluid has good shear resistance and temperature resistance. The viscosity of NaOEr/HTAB can reach above 50 mPa⋅s after sheared for 60 min at the conditions of 170 s−1 and 80 °C. This study provides an anionic clean fracturing fluid and broaden the application of viscoelastic surfactants in oilfield development.

High-Entropy Lithium Niobate Nanocubes for Photocatalytic Water Splitting under Visible Light.

The vast compositional space available in high-entropy oxide semiconductors offers unique opportunities for electronic band structure engineering in an unprecedented large room. In this work, with wide band gap semiconductor lithium niobate (LiNbO3) as a model system, we show that the substitutional addition of high-entropy metal cation mixtures within the Nb sublattice can lead to the formation of a single-phase solid solution featuring a substantially narrowed band gap and intense broadband visible light absorption. The resulting high-entropy LiNbO3 [denoted as Li(HE)O3] crystallizes as well-faceted nanocubes; atomic-resolution imaging and elemental mapping via transmission electron microscopy unveil a distinct local chemical complexity and lattice distortion, characteristics of high-entropy stabilized solid solution phases. Because of the presence of high-entropy stabilized Co2+ dopants that serve as active catalytic sites, Li(HE)O3 nanocubes can accomplish the visible light-driven photocatalytic water splitting in an aqueous solution containing methanol as a sacrificial electron donor without the need of any additional co-catalysts.

Current carrying tribological properties of multi arc ion plated titanium nitride doped silver coating

Sliding electrical contact materials play a crucial role in the transmission and conversion of electrical energy, but due to various factors such as force, electricity, and heat, the interface exhibits complex wear behavior. A single solid or liquid lubrication system can no longer meet the growing performance requirements of current carrying tribology. In this study, a TiN-Ag coating was prepared using multi arc ion plating technology, and a solid–liquid composite lubrication system was formed with ionic liquid and polyurea grease, respectively. Through current carrying friction and wear tests, their tribological properties, electrical contact resistance(ECR) values, and stability were tested, and compared with the results obtained during dry friction. The coating and worn surfaces were analyzed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results indicated that compared with dry friction, TiN-Ag coatings lubricated with ionic liquids and polyurea grease showed higher friction reduction, wear resistance, and conductivity, especially the synergistic effect between ionic liquids and coatings is prominent. The behavior of ionic liquids under voltage was analyzed, and it was found that ionic liquids formed a physical adsorption film composed of a mixture of anions and cations on the worn surface. The ordered layered structure improved the tribological performance of the system.

Supported heterogeneous catalyst of the copper oxide nanoparticles and nanozeolite for binary dyes mixture degradation: Machine learning and experimental design

The present work aims to evaluate the photocatalytic activity of an alternative supported nanocatalyst (nANA@CuO-NPs) for a binary dye mixture (Crystal Violet and Methylene Blue, labeled CV:MB) under visible light and study to propose a model to predict the reaction pathway for the process. An experimental design (Central Composite Rotational Design with 3 factors and 2 levels – CCRD 23) was proposed to evaluate the ideal condition of the CV/MB photodegradation and four machine learning algorithms (Decision Tree, Random Forest, Xtreme Gradient Boosting and Artificial Neural Network-Multilayer Perceptron) were used to predict the main degradation products. The supported nanocatalyst was characterized by X-ray diffraction (XRD), Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy, N2 porosimetry, Diffuse Reflectance Spectroscopy (DRS), Field Emission Gun – Scanning Electron Microscope (FEG-SEM), Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), zeta potential (ZP) and zero charge point (pHZCP). XRD diffractogram of the nANA@CuO-NPs showed the tenorite and analcime phases with crystallite size and microstrain ranging from 0.319 to 22.35 nm and 6.48–454 × 10−3. ATR-FTIR spectra indicated the presence of functional groups characteristic of copper oxide nanoparticles (CuO-NPs) and nanozeolite analcime (nANA) on the supported catalyst, confirming the impregnation method. SEM micrographs indicated a heterogeneous surface with clusters (CuO-NPs and nANA@CuO-NPs) and homogenous surface for nANA, while the EDX showed the nANA with Si/Al < 2 (low-silica nanozeolite) and nANA@CuO-NPs with the presence in the elemental composition of the catalytic support (nANA) and the photoactive phase (CuO-NPs). Supported nanocatalyst showed physio-chemical stability due to the electrostatic interactions (ZP = 51.5 ± 0.5 mV) and band gap energy (Eg) of the 1.67 eV allowing its applicability under visible radiation. XGB algorithm resulted in the best predictive model (R2 equals 0.8106 and 0.9880 for training and testing, RMSE < 6.0), confirming the obtention of carbon dioxide (m/z = 44), water (m/z = 18) and low-molar mass compounds at the final of the binary dye mixture degradation reaction. The ideal condition for the by CCRD 23 for the degradation of the dye mixture was [CV:MB] = 135 mg/L, [nANA@CuO-NPs] = 1 g/L and pH = 7 with 82.84 % (k = 0.0089 min−1). Therefore, the synthesized nanocatalyst proved its good photocatalytic activity toward a cationic dye mixture of CV and MB dyes. Furthermore, this work confirms the potentiality of machine learning algorithms to develop predictive models for the elucidation of the degradation reaction pathway of organic dyes.

Surface and Bulk Stabilization of Silicon Anodes with Mixed-Multivalent Additives: Ca(TFSI)2 and Mg(TFSI)2.

Silicon is drawing attention as an emerging anode material for the next generation of lithium-ion batteries due to its higher capacity compared with commercial graphite. However, silicon anions formed during lithiation are highly reactive with binder and electrolyte components, creating an unstable SEI layer and limiting the calendar life of silicon anodes. The reactivity of lithium silicide and the formation of an unstable SEI layer are mitigated by utilizing a mixture of Ca and Mg multivalent cations as an electrolyte additive for Si anodes to improve their calendar life. The effect of mixed salts on the bulk and surface of the silicon anodes was studied by multiple structural characterization techniques. Ca and Mg ions in the electrolyte formed relatively thermodynamically stable quaternary Li-Ca-Mg-Si Zintl phases in an in situ fashion and a more stable and denser SEI layer on the Si particles. These in turn protect silicon particles against side reactions with electrolytes in a coin cell. The full cell with the mixed cation electrolyte demonstrates enhanced calendar life performance with lower measured current and current leakage in comparison to that of the baseline electrolyte due to reduced side reactions. Electron microscopy, HR-XRD, and solid-state NMR results showed that electrodes with mixed cations tended to have less cracking on the electrode surface, and the presence of mixed cations enhances cation migration and formation of quaternary Zintl phases stabilizing the bulk and forming a more stable SEI in comparison to baseline electrolyte and electrolyte with single multivalent cations.

The Electrocatalytic Activity of Au Electrodes Changes Significantly in Various Na+/K+ Supporting Electrolyte Mixtures

The potential of maximum entropy (PME) is an indicator of extreme disorder at the electrode/electrolyte interface and can predict changes in catalytic activity within electrolytes of varying compositions. The laser‐induced current transient technique is employed to evaluate the PME for Au polycrystalline (Aupc) electrodes immersed in Ar‐saturated cation electrolyte mixtures containing potassium and sodium ions at pH = 8. Five cation ratios (0.5 M K2SO4:0.5 M Na2SO4 = 0:1, 0.25:0.75, 0.5:0.5, 0.75:0.25, and 1:0) are explored, considering earlier studies that unveil cation‐dependent shifts at near‐neutral pH. Moreover, for all electrolyte compositions, electrochemical impedance spectroscopy is utilized to determine the double‐layer capacitance (CDL), the minimum of which should be close to the potential of zero charge (PZC). By correlating cation molar ratios with the PMEs and PZCs, the impact on the model oxygen reduction reaction (ORR) activity, assessed via the rotating disk electrode method, is analyzed. The results demonstrate a linear relationship between electrolyte cation mixtures and PME, while ORR activity exhibits an exponential trend. This observation validates the PME–activity link hypothesis, underscoring electrolyte components’ pivotal role in tailoring interfacial properties for electrocatalytic systems. These findings introduce a new degree of freedom for designing optimal electrocatalytic systems by adjusting various electrolyte components.

NMR investigation of multi-scale dynamics in ionic liquids containing Li+ and La3+: From vehicular to hopping transport mechanism

The dynamics in mixtures of ionic liquid and monoatomic cations has been studied at different time scales ranging from the nanosecond up to the second. The mixtures were composed of cholinium bis(trifluoromethanesulfonyl)imide ([Chol][TFSI]) and LiTFSI, with LiTFSI mole fraction, ▪, spanning from 0 to 0.5 (saturated solution), and [Chol][TFSI] and ▪ from 0 to 0.12. The translational self-diffusion coefficients of ▪, ▪ and ▪ have been measured, along with NMR their relaxation times at various magnetic fields, in order to decipher the intertwined dynamics between the ions, and to reveal how the local dynamics impact the long range translational diffusion. When the concentrations of lithium and lanthanum are increased in the liquid, the long range dynamics of all the ions drop. In the case of LiTFSI, the self-diffusion coefficient of lithium becomes higher than the one of TFSI at high concentration, revealing a change in lithium transport mechanisms. The NMR relaxation data confirm this change, showing a clearer transition at ▪. It is interpreted as a change from a vehicular transport mechanism of the lithium below ▪ to a hopping mechanism above. A similar crossover seems to occur in the lanthanum solutions. This phenomenon seems correlated to the departure of the hydroxyl group of the organic cation from the lithium solvation shell.

Cation/Anion-Dual regulation in Na3MnTi(PO4)3 cathode achieves the enhanced electrochemical properties of Sodium-Ion batteries

Na3MnTi(PO4)3 (NMTP) emerges as a promising cathode material with high-performance for sodium-ion batteries (SIBs). Nevertheless, its development has been limited by several challenges, including poor electronic conductivity, the Mn3+ Jahn-Teller effect, and the presence of a Na+/Mn2+ cation mixture. To address these issues, we have developed a cation/anion-dual regulation strategy to activate the redox reactions involving manganese, thereby significantly enhancing the performance of NMTP. This strategy simultaneously enhances the structural dynamics and facilitates rapid ion transport at high rates by inducing the formation of sodium vacancy. The combined effects of these modifications lead to a substantial improvement in specific capacity (79.1 mAh/g), outstanding high-rate capabilities (35.9 mAh/g at 10C), and an ultralong cycle life (only 0.040 % capacity attenuation per cycle over 250 cycles at 1C for Na3.34Mn1.2Ti0.8(PO3.98F0.02)3) when used as a cathode material in SIBs. Furthermore, its performance in full cell demonstrates impressive rate capability (44.4 mAh/g at 5C) and exceptional cycling stability (with only 0.116 % capacity decay per cycle after 150 cycles at 1C), suggesting its potential for practical applications. This work presents a dual regulation strategy targeting different sites, offering a significant advancement in the development of NASICON phosphate cathodes for SIBs.

Highly selective transport of Ag+ from a mixture of some bivalent cations using polymer inclusion membrane by 2,2′-dithio-bis-benzothiazole as a carrier

Highly selective transport of Ag+ from a mixture of some bivalent cations using polymer inclusion membrane by 2,2′-dithio-bis-benzothiazole as a carrier

Structural analysis of C8H6˙+ fragment ion from quinoline using ion-mobility spectrometry/mass spectrometry.

This study investigated the structures of fragment ions derived from the quinoline (C9H7N) radical cation using ion-mobility spectrometry and mass spectrometry. Ion mobility and mass analysis revealed that C8H6˙+ is the primary dissociation product resulting from the loss of HCN during collision-induced dissociation of the quinoline radical cation. The reduced mobility (K0) of the C8H6˙+ fragment product in helium gas was measured over a range of reduced electric fields (E/N = 20.8-27.4 Td) at room temperature. The experimental K0 values indicated that C8H6˙+ is a mixture of phenylacetylene and pentalene radical cations. Furthermore, quantum chemical calculations revealed two potential energy surfaces delineating the loss of HCN from the quinoline radical cation to form phenylacetylene radical cations.

Технология переработки сухих отходов сорбции и растворов хлоридов сурьмы

Reducing the loss of valuable components during the processing of complex gold-antimony ores, increasing the extraction of antimony during the flotation of sulfide minerals, is an urgent scientific problem. The aim of the study is to maximize the extraction of gold and antimony from dry sorption waste after gold cyanidation, and to improve the reagent regime of the antimony mineral flotation process. Research objectives are as follows: evaluation of the technology efficiency for processing dry sorption waste; extraction of gold from the cake of acidic leaching of antimony; production of various antimony-containing products from solutions of antimony chlorides; study of the possibility of replacing lead with a mixture of zinc and copper cations to hydrophobize the surface of antimony sulfide minerals during flotation. The object of the research is man-made and natural mineral raw materials containing gold and antimony. The following research methodology and methods are used: information analysis, evaluation of existing scientific developments, methods of theoretical and experimental research. A new technological solution has been proposed: acidic (a mixture of hydrochloric acid and hydrogen hydroxide) hydrometallurgical technology for processing dry sorption waste in order to extract gold and antimony. Acid treatment makes it possible to completely transfer antimony into solution, significantly improves the quality of the cake for subsequent cyanidation and gold extraction, reduces the volume of material for processing by cyanidation, and simplifies cyanidation technology. Sb2S3 activation and the possibility of lead (Pb(NO3) replacement have been studied 2) a mixture of zinc and copper (ZnSO4 and CuSO4) during the flotation of antimony ores from the Khipkoshinsky deposit in the Transbaikal Region. This has made it possible to create favorable conditions for interaction with xanthogenate and hydrophobize the surface of sulfide minerals. Theoretically, hydrogen sulfide substitutes such as NaCNS, KCNS, CuCNS for use in the flotation process were evaluated.

Facile Fabrication of Positively Charged Nanofiltration Membrane for the Effective Separation of Cationic Dyes and Salt Mixtures

Facile Fabrication of Positively Charged Nanofiltration Membrane for the Effective Separation of Cationic Dyes and Salt Mixtures