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Investigation was conducted on the failure of the crankshaft made from 48MnV alloy steel used in automotive engines. Magnetic flaw defects were detected at the transition fillet between the third main journal and the counterweight of the crankshaft. Macroscopic examination, chemical composition analysis, metallographic analysis, and scanning electron microscopy observation were performed on the crankshaft samples. The testing results were summarized, and the causes of the crankshaft cracking were systematically analyzed. The results indicate that longitudinal cracks occurred on the surface of the crankshaft journal due to the combined effect of thermal stress and normal operating stress, exceeding its load-bearing capacity. These cracks propagated inward, forming magnetic flaw cracks, ultimately leading to crankshaft failure.

In order to improve the comprehensive performance of titanium alloy, the mechanical ball milling method was used to optimize the preparation of composite powder by different ball milling time, rotation speed and SiCp content. SiCp/TC11 composites were prepared by selective laser melting (SLM) technology. The results show that the milling speed, time and SiC content have an effect on the morphology, size and distribution of the composite powder. Compared with TC11, the hardness of the composite prepared by SLM process is 426,723 HV, which is increased by 15,10 %, and the enhancement effect of SiCp is successfully realized.The research results provide a theoretical basis for obtaining high-quality aerospace titanium alloy parts.

This study presents the results of research into the influence of the time of the plasma nitriding process on the microstructure of the coatings obtained on cold-work tool steels X153CrMoV12 and X165CrV12. The processes were carried out under industrial conditions using an Ionit system (Oerlikon Metaplas) with variable process times of 2, 4 and 6 hours. Nitriding mixture consisting of 5 % nitrogen and 95 % hydrogen was chosen, which allowed the expected diffusion layer to be obtained without a white layer (composed of iron nitrides). Analysis of relative elemental concentrations indicates that the presence and content of nitride-forming elements influences the formation of alloy additive nitrides in the microstructure of the diffusion layer. Nitrides of alloying additives, present in the diffusion layer, indicating that investigated steels are the most suitable for plasma nitriding.

Herein, a mechanochemical approach was developed for recover the cobalt and from spent lithium-ion batteries using a high-concentration chloride solution. Effect of parameters on the leaching efficiency of cobalt was studied. 97, 6% of Co was recovered under optimum conditions: rotation speed 500 r/min, S/L ratio: 1:150 g/ml, ball/material ratio 25:1 g/g, milling time 30 min, respectively. The dissolved cobalt was recovered by selective precipitation method to ensure that the recycled Co can be reused for lithium-ion battery production. This research presents a highly efficient and environmentally friendly approach for recovering cobalt from spent LiBs. [ABSTRACT FROM AUTHOR]

Herein, a mechanochemical approach was developed for recover the cobalt and from spent lithium-ion batteries using a high-concentration chloride solution. Effect of parameters on the leaching efficiency of cobalt was studied. 97, 6% of Co was recovered under optimum conditions: rotation speed 500 r/min, S/L ratio: 1:150 g/ml, ball/material ratio 25:1 g/g, milling time 30 min, respectively. The dissolved cobalt was recovered by selective precipitation method to ensure that the recycled Co can be reused for lithium-ion battery production. This research presents a highly efficient and environmentally friendly approach for recovering cobalt from spent LiBs.

The waste lithium cobalt acid batteries were utilized as raw materials to separate out LiCoO2 cathode material. Citric acid was used to leach cathode material, and LiCoO2 leaching solution was electrodeposited to obtain cobalt plating, in the meantime the Li2+ ions were enriched. The optimized conditions of leaching process are 1,2 mol/L citric concentration and 0,35 mol/L sodium thiosulfate concertation, the leaching efficiency of cobalt and lithium is 97,5 % and 97,0 % respectively. At pH 4, the smooth cobalt coating with fine grains can be obtained on the surface of the stainless-steel cathode.

In this paper, in order to achieve the resource utilization of metallurgical industry waste, the cracking resistance of magnesium oxysulfate cement coatings using granulated blast furnace slag powder and iron tailings powder as fillers was studied, x-ray Diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the hydration products. The results show that an appropriate amount of slag powder and iron tailings powder can make the internal structure of the coating more compact, the surface smooth and effectively reduce the generation of cracks.

Waste chromium production sludge from the Dubersay tailings dump is present in huge quantities with a magnesium oxide content of up to 40 %. The chrome-containing waste was sintered at 1 100 °C, the resulting sinter was mixed with sulphuric acid when heated to 300 °C. The resulting mixture after heating was leached with water at 90 °C, the solid precipitate was washed and dried to yield a chrome concentrate containing 55,4 % Cr2O3, 8,2 % SiO2. Evaporation of the purified solution produces magnesium sulphate which is a magnesium fertilizer.

This study aimed to obtain and investigate ZnCr2Se4 single crystals doped with rhenium. The single crystals were obtained by applying chemical vapour transport. An X-ray study confirmed the cubic ( F d 3 ¯ m ) structure of the tested crystals. Thermal, magnetic, electrical, and specific heat measurements accurately determined the physicochemical characteristics, which revealed that the obtained single crystals are p-type semiconductors with antiferromagnetic order below the Néel temperature TN = 21.7 K. The Debye temperature had a value of 295 K. The substitution of Re-paramagnetic ions, possessing a screened 5d-shell, in place of Zn-diamagnetic ions, caused an increase in the activation energy, Fermi energy, and Fermi temperature compared to the pure ZnCr2Se4. The boost of the dc magnetic field induced a shift of TN towards lower temperatures and a spin fluctuation peak visible at Hdc = 40 and 50 kOe. The obtained single crystals are thermally stable up to 1100 °C. [ABSTRACT FROM AUTHOR]

The article presents the results of the studies related to the development of hardening, antifriction, heat-resistant, corrosion-resistant coatings. There have been considered the models of concentration supercooling associated with the presence of a radial concentration gradient of metal nitride impurity; Benard cells, the occurrence of which is caused by the presence of a vertical temperature gradient; a cellular dislocation structure associated with the presence of plastic deformations in the coating; the emergence of auto-waves in the most diverse environments, including living beings. From the studies presented in the work, it follows that self-organization of forming coatings can occur only under conditions of a large value of the surface energy. [ABSTRACT FROM AUTHOR]

The article presents the results of the studies related to the development of hardening, antifriction, heat-resistant, corrosion-resistant coatings. There have been considered the models of concentration supercooling associated with the presence of a radial concentration gradient of metal nitride impurity; Benard cells, the occurrence of which is caused by the presence of a vertical temperature gradient; a cellular dislocation structure associated with the presence of plastic deformations in the coating; the emergence of auto-waves in the most diverse environments, including living beings. From the studies presented in the work, it follows that self-organization of forming coatings can occur only under conditions of a large value of the surface energy.

The article deals with the research of component composition and catalitic reactivity of metallurgical waste products. The slags component composition was investigated by X-ray fluorescence analysis. The slag stuff has been modified with alkali (NaOH) and mineral acids (HNO3, H2SO4, HCI and H3PO4), and their catalytic reactivity in the catalytic decomposition of ethyl alcohol and hydrogen peroxide has been determined for the first time. The revealed catalytic reactivity of the slag staff for the decomposition of ethyl alcohol and hydrogen peroxide indicates the need for a more detailed research and development of an industrial non-ferrous waste treatment technology.

The results of studies on the production of pellets for the metallurgical stage based on manganese concentrate with a manganese content of 34 %, obtained from waste manganese-containing sludge, are presented. Kaolin and highiron diatomite in combination with calcium oxide and coke were tested as binder components of charges. Manganese- containing pellets were produced by composition pelletizing in a Eirich high-speed mixer-granulator. The size of pellets in the form of rounded granules was in the range of 5 - 10 mm. Sintering roasting temperature of pellets was 1150 - 1200°C. Strength of roasted pellets was 1 313 with kaolin as binder, 1 940 with diatomite, and diatomite with lime addition – 2058 N/pellet respectively.

Electrodeposition of multilayers continues to grow and diversify. Research is still underway on the adaptation of multilayer systems to new applications in various industries. Cu/Ni multilayers are still very commonly used for practical purposes. In this work, the functional properties of selected multilayer systems with different layers quantity and thicknesses in nanoscale were investigated. The Cu and Ni layers were electrolytically deposited on a low carbon steel substrate and obtained systems were subjected to structural and anticorrosion properties study. The electrochemical parameters were determined by potentiodynamic method and the surface evaluation of the systems after corrosion tests was also carried out.

Electrodeposition of copper and nickel from acidic solutions using a rotating cathode coated with liquid and solid gallium has been studied. Methods of nonferrous metals separation from the gallium coating of the cathode were determined. Electrodeposition on the liquid gallium coating was carried out at a temperature of 50 °C. Separation of metals from gallium was performed by alkaline treatment. On the solid gallium cathode coating, electrodeposition was performed at 25 °C. The metal precipitates were separated from the cathode after it was heated. When using cathode with hard gallium coating the reduction of electric power consumption for copper by 85 % and for nickel by 15 % was obtained.

The material composition of kaolin raw materials with the content of Al2O3 – 17,21; SiO2 – 66,27; Fe2O3 – 0,51; TiO2 0,574 was studied. The main valuable minerals are kaolinite, halloysite, muscovite, quartz, rare marks of tourmaline, ilmenite. Particle size analysis of kaolin raw materials shows that the largest mass is represented by the size class (- 0,05+0 mm) – 43,08 %. 79,74 % of alumina with its content of 32,0 % is in the size class (- 0,05+0 mm), and it can be used as a raw material for further processing into alumina or as a universal filler for production of paper, rubber, cable, plastic and perfumery products.

The results of studies on the production of pellets for the metallurgical stage based on manganese concentrate with a manganese content of 34 %, obtained from waste manganese-containing sludge, are presented. Kaolin and highiron diatomite in combination with calcium oxide and coke were tested as binder components of charges. Manganese-containing pellets were produced by composition pelletizing in a Eirich high-speed mixer-granulator. The size of pellets in the form of rounded granules was in the range of 5 - 10 mm. Sintering roasting temperature of pellets was 1 150 - 1 200°C. Strength of roasted pellets was 1 313 with kaolin as binder, 1 940 with diatomite, and diatomite with lime addition - 2058 N/pellet respectively. [ABSTRACT FROM AUTHOR]

The article deals with the research of component composition and catalitic reactivity of metallurgical waste products. The slags component composition was investigated by X-ray fluorescence analysis. The slag stuff has been modified with alkali (NaOH) and mineral acids (HNO3, H2SO4, HCI and H3PO4), and their catalytic reactivity in the catalytic decomposition of ethyl alcohol and hydrogen peroxide has been determined for the first time. The revealed catalytic reactivity of the slag staff for the decomposition of ethyl alcohol and hydrogen peroxide indicates the need for a more detailed research and development of an industrial non-ferrous waste treatment technology. [ABSTRACT FROM AUTHOR]

The high P content in steel slag limits its recycling during the smelting process, and the P can be effectively removed from the steel slag by gasification dephosphorization. In this experiments, the effects of temperature, basicity, and FeO for gasification dephosphorization rate are studied through thermodynamic calculations. The Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS) analysis that microscopic morphology of slag before and after reduction. In addition, a model is established to describe the phosphorus migration behavior of gasification dephosphorization process.

On the territory there are phosphorus-containing wastes - phosphorus slags, the basis of which is volostanite. The study of phosphorus slag as a uranium sorbent is of theoretical and practical interest. In the course of the research, comparable data were obtained on the sorption of the initial and activated slag by different reagents. The optimal conditions for the activation of phosphorus slag in order to increase its sorption properties have been determined.

The work presents the results of studies on obtaining ferromanganese concentrate from technogenic manganesecontaining raw materials with grain size less than 10 mm. It is found that the main valuable minerals of the feedstock are psilomelane, pyrolusite, bementite; among the rock-forming minerals, quartz and kaolinite, often saturated with finely dispersed iron compounds, prevail. Sieving and concentration of raw materials of - 10 + 5 mm and - 2 + 0,2 mm in two-chamber jigging machine with separation of two concentrates and tailingпs allowed to obtain a joint manganese concentrate with 35,1 % manganese content, 11,5 % iron content with 78,23 % manganese recovery. The obtained manganese concentrate is suitable for further metallurgical processing.

The paper contains the laboratory study results for the flotation processing of gold-containing tailings with the use of the composite reagent (CF). The CF flotation reagent is a microemulsion from a composition of sodium butyl xanthate and reaflot. A gold-containing concentrate was obtained with a gold content of 6,7 g/t with a recovery of 59,71 % in the basic mode. The use of the CF composite flotation reagent increases the gold extraction into the gold-containing concentrate by 3,77 %, as compared with the main collector - sodium butyl xanthate. The consumption of CF flotation reagent is reduced by 20 %.

The paper presents the results of studies intended to separate minerals by density in a heavy liquid. Chemical analysis found that the manganese content amounts to 16,32 % in the studied sludge sample. Manganese sludge was separated by specific gravity in M-45 heavy liquid (the aqueous solution of a complex salt of barium iodides and cadmium with a density of 3 000 kg/m3). The tailings sample was fractioned by specific gravity in the material with a particle size of -2,5 + 1,0 mm; -1,0 + 0,5 mm and -0,5 + 0 mm. The manganese content in the heavy fraction of 3 000 kg/m3 was 32,5 %. The manganese content in the light fraction varied from 1,7 to 2,5 %. Light fractions were represented by aggregates of quartz and calcite with manganese minerals. According to X-ray phase analysis, heavy fractions were mainly represented by minerals braunite, bixbyite, barite and hematite.

The article presents the results of research on the synthesis of strong chrome pellets based on concentrates obtained by enrichment of chrome sludge. To obtain strong fired pellets from the concentrates, it is proposed to use a ferrosilico- calcium reagent as a binder, which makes it possible to increase the strength of the pellets by 2-3 times in comparison with the technology operating at “Donskoy Ore Mining and Processing Plant”. This excludes the supply of fluxing reagents during electric arc smelting of raw materials to high-carbon ferrochrome. Pellets from concentrates obtained during the processing of tailings from the Dubersay sludge storage have increased strength up to 5 330 N/pellet at a roasting temperature of 1 200 °C.

The paper presents research on the processing of waste dust from the electrical smelting of ilmenite concentrates with the removal of silicon from them by the fluoride method. The optimum conditions for fluorination of electric smelting dust were determined, at which the degree of silicon fluoride sublimation was 84,2 %. The silicon-containing sublime obtained in the presence of an ammonia agent has been studied. Based on the results of thermal analysis and studies on the effect of process duration the optimum pyrolysis modes that provide the separation of fluoride and silicon oxide: temperature 530 - 560 °C and duration of 60 - 80 min have been determined. The content of silicon oxide in the obtained product was 96,3 %.

The coke reduction gasification dephosphorization experiments were conducted on converter slag with FeO contents of 15 %, 20 %, 30 % and 35 %, respectively. Thermodynamic calculations , Scanning Electron Eicroscope (SEM) and Energy Dispersive Spectrometer (EDS) showed that the actual reduction Gibbs free energy of P2O5 was less than that of FeO for the coke reduction converter slag product of P2, and the reactive driving force of P2O5 was greater under high FeO conditions. With the increase of FeO content, the gasification dephosphorization rate showed a trend of increasing first and then decreasing. After gasification dephosphorization, the presence of the Fe phase will adsorb more P elements, so the high FeO content is beneficial to increase the P2O5 activity, which is conducive to the gasification dephosphorization reaction.

The paper presents the method of forming TiO2 coatings on 100Cr6 steel using the ALD method and assessing the properties of the obtained coatings. The coatings were assessed in terms of surface morphology, chemical composition, contact angle and tribological properties. The performed tribological tests show that TiO2 coatings are characterized by lower resistance to motion. During measuring the geometric structure of surfaces on samples with TiO2 coating, smaller wear traces were recorded than for 100Cr6 steel. The obtained values of the contact angles prove that the 100Cr6 steel coated with TiO2 is more hydrophobic than the uncoated 100Cr6 steel. TiO2 coatings can be used in low-loaded tribological systems and as barrier coatings.

In this study, the influence of the variable content of Al, Ni, Fe on the grain refining and the change of mechanical properties of aluminium bronze cast into iron ingot mould was investigated. The ingots were tested for susceptibility to cold plastic working in the rolling process. It was shown that a small amount of iron (0,8 wt. %) influenced a significant level of grain refining and improvement of mechanical properties. For alloys with an increased content of Al, Fe and Ni, the maximum value of the true strain of 0,36 was achieved in the cold rolling process. The possibility of achieving similar mechanical properties for alloy with reduced content of alloying elements was demonstrated after applying the true strain of 0,61.

Cu-Ag alloys may be used in the form of sheets for the construction of bitter type magnets. The paper presents results of laboratory studies on obtaining of ingots from Cu-(1÷7wt.%)Ag alloys, solution treatment and aging and rolling process. Has been shown influence of different heat treatment and plastic deformation on the mechanical and electrical properties. The microstructural analysis of castings and sheets with the use of scanning electron microscopy (SEM) is also presented.

The article presents the results of laboratory research on the production of multi-core superconducting wires. Multicore wires containing boron and magnesium powders in a copper matrix were obtained in the drawing process combined with intermediate heat treatment. The wires contains powder cores were sintered under high isostatic pressure to produce the MgB2 superconducting phase. The critical temperature for the composite’s superconducting state was determined. The macrostructure and energy dispersion (EDX) analysis of multi-core wires was also presented.

The material composition of the gold-containing tailings of the flotation beneficiation of the Zholymbet ore deposit was studied. It was determined that the samples contain 0,9 g/t of gold, 1,22 g/t of silver. The flotation technologices of technogenic gold-containing raw materials with the use of basic and ultramicroheterogeneous flotation reagents were developed. The content of gold in a draft gold concentrate, in comparison with the basic mode, increases by 2,28 g/t - with 19,56 to 21,84 g/t. The extraction of gold in concentrate increased - by 5,52 % - with 66,07 % to 71,59 %. Thus the consumption of collectors is cut for 50 g/t, with 130 to 80 g/t.

Electrodeposition of multilayers continues to grow and diversify. Research is still underway on the adaptation of multilayer systems to new applications in various industries. Cu/Ni multilayers are still very commonly used for practical purposes. In this work, the functional properties of selected multilayer systems with different layers quantity and thicknesses in nanoscale were investigated. The Cu and Ni layers were electrolytically deposited on a low carbon steel substrate and obtained systems were subjected to structural and anticorrosion properties study. The electrochemical parameters were determined by potentiodynamic method and the surface evaluation of the systems after corrosion tests was also carried out. [ABSTRACT FROM AUTHOR]

The material composition of the gold-containing tailings of the flotation beneficiation of the Zholymbet ore deposit was studied. It was determined that the samples contain 0,9 g/t of gold, 1,22 g/t of silver. The flotation technologices of technogenic gold-containing raw materials with the use of basic and ultramicroheterogeneous flotation reagents were developed. The content of gold in a draft gold concentrate, in comparison with the basic mode, increases by 2,28 g/t - with 19,56 to 21,84 g/t. The extraction of gold in concentrate increased - by 5,52 % - with 66,07 % to 71,59 %. Thus the consumption of collectors is cut for 50 g/t, with 130 to 80 g/t. [ABSTRACT FROM AUTHOR]

Cu-Ag alloys may be used in the form of sheets for the construction of bitter type magnets. The paper presents results of laboratory studies on obtaining of ingots from Cu-(1÷7wt.%)Ag alloys, solution treatment and aging and rolling process. Has been shown influence of different heat treatment and plastic deformation on the mechanical and electrical properties. The microstructural analysis of castings and sheets with the use of scanning electron microscopy (SEM) is also presented. [ABSTRACT FROM AUTHOR]

The article presents the results of laboratory research on the production of multi-core superconducting wires. Multicore wires containing boron and magnesium powders in a copper matrix were obtained in the drawing process combined with intermediate heat treatment. The wires contains powder cores were sintered under high isostatic pressure to produce the MgB2 superconducting phase. The critical temperature for the composite's superconducting state was determined. The macrostructure and energy dispersion (EDX) analysis of multi-core wires was also presented. [ABSTRACT FROM AUTHOR]

The paper presents the method of forming TiO2 coatings on 100Cr6 steel using the ALD method and assessing the properties of the obtained coatings. The coatings were assessed in terms of surface morphology, chemical composition, contact angle and tribological properties. The performed tribological tests show that TiO2 coatings are characterized by lower resistance to motion. During measuring the geometric structure of surfaces on samples with TiO2 coating, smaller wear traces were recorded than for 100Cr6 steel. The obtained values of the contact angles prove that the 100Cr6 steel coated with TiO2 is more hydrophobic than the uncoated 100Cr6 steel. TiO2 coatings can be used in low-loaded tribological systems and as barrier coatings. [ABSTRACT FROM AUTHOR]

In this study, the influence of the variable content of Al, Ni, Fe on the grain refining and the change of mechanical properties of aluminium bronze cast into iron ingot mould was investigated. The ingots were tested for susceptibility to cold plastic working in the rolling process. It was shown that a small amount of iron (0,8 wt. %) influenced a significant level of grain refining and improvement of mechanical properties. For alloys with an increased content of Al, Fe and Ni, the maximum value of the true strain of 0,36 was achieved in the cold rolling process. The possibility of achieving similar mechanical properties for alloy with reduced content of alloying elements was demonstrated after applying the true strain of 0,61. [ABSTRACT FROM AUTHOR]

The coke reduction gasification dephosphorization experiments were conducted on converter slag with FeO contents of 15 %, 20 %, 30 % and 35 %, respectively. Thermodynamic calculations, Scanning Electron Eicroscope(SEM) and Energy Dispersive Spectrometer (EDS) showed that the actual reduction Gibbs free energy of P2O5 was less than that of FeO for the coke reduction converter slag product of P2, and the reactive driving force of P2O5 was greater under high FeO conditions. With the increase of FeO content, the gasification dephosphorization rate showed a trend of increasing first and then decreasing. After gasification dephosphorization, the presence of the Fe phase will adsorb more P elements, so the high FeO content is beneficial to increase the P2O5 activity, which is conducive to the gasification dephosphorization reaction. [ABSTRACT FROM AUTHOR]

Based on the composition detection results of steel inclusions, it is found that the steel-heaping reason of cold heading wire is caused by the slag entrapment in steelmaking process. In view of the above reasons, by controlling the fluctuation of liquid level of tundish, controlling the fluctuation of continuous casting speed, optimizing the thickness of covering slag and tundish cover powder, the phenomenon of steel-heaping in the rolling process can be effectively reduced when producing Q195 and other cold heading steel. It is of great significance to guide process improvement.

There has been carried out thermodynamic modeling of phase transformations of the Fe-Cr Ni alloy alloyed with titanium and niobium in order to predict the phase composition and to substantiate the concentration of alloying elements of the experimental alloy for parts of metallurgical equipment. The results of microstructural analysis and phase composition of an experimental heat-resistant alloy are presented.

The research presents the results of laboratory studies on the flotation processing of mature copper tailings using KF2 composite reagent. KF2 flotation agent is a mixture of sodium butyl xanthate, thionocarbamate, and composite aerofloat at a ratio of 1:1:3. In the base regime, a rough copper concentrate obtained had a copper content of 10,9 % with a recovery of 74,91 %. The use of KF2 composite flotation reagent increases the extraction of copper into rough copper concentrate by 5,31 %. This made it possible to obtain a rough copper concentrate with a copper content of 13,0 % and a recovery of 80,22 %. Consumption of KF2 flotation reagent is halved compared to the basic sodium butyl xanthate collector.

The article presents the results of tests of Zn-5Al coatings obtained on reinforcement bars made of B500SP steel. The microstructure using Scanning electron microscopy (SEM) and chemical composition in micro-regions using Energy dispersive spectroscopy (EDS) are shown. The electrochemical parameters of the corrosion process of the coatings were determined and the mechanical properties of the reinforcement bars after the coating were tested. It was found that the coating consists of the outer layer consisting of hypoeutectic regions of Al solution in Zn (α) and the ZnAl eutectic (α+β), and a diffusion layer composed of FeAl3 phase. Potentiodynamic tests have shown that the Zn- Al5 coating provides sacrificial protection for the reinforcement steel and has a much lower corrosion current density compared to the traditional zinc coating.

The paper presents research on the processing of waste dust from the electrical smelting of ilmenite concentrates with the removal of silicon from them by the fluoride method. The optimum conditions for fluorination of electric smelting dust were determined, at which the degree of silicon fluoride sublimation was 84,2 %. The silicon-containing sublime obtained in the presence of an ammonia agent has been studied. Based on the results of thermal analysis and studies on the effect of process duration the optimum pyrolysis modes that provide the separation of fluoride and silicon oxide: temperature 530 - 560 °C and duration of 60 - 80 min have been determined. The content of silicon oxide in the obtained product was 96,3 %. [ABSTRACT FROM AUTHOR]

The article presents the results of research on the synthesis of strong chrome pellets based on concentrates obtained by enrichment of chrome sludge. To obtain strong fired pellets from the concentrates, it is proposed to use a ferrosilico-calcium reagent as a binder, which makes it possible to increase the strength of the pellets by 2-3 times in comparison with the technology operating at “Donskoy Ore Mining and Processing Plant”. This excludes the supply of fluxing reagents during electric arc smelting of raw materials to high-carbon ferrochrome. Pellets from concentrates obtained during the processing of tailings from the Dubersay sludge storage have increased strength up to 5 330 N/pellet at a roasting temperature of 1 200 °C. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies intended to separate minerals by density in a heavy liquid. Chemical analysis found that the manganese content amounts to 16,32 % in the studied sludge sample. Manganese sludge was separated by specific gravity in M-45 heavy liquid (the aqueous solution of a complex salt of barium iodides and cadmium with a density of 3 000 kg/m³ ). The tailings sample was fractioned by specific gravity in the material with a particle size of -2,5 + 1,0 mm; -1,0 + 0,5 mm and -0,5 + 0 mm. The manganese content in the heavy fraction of 3 000 kg/m³ was 32,5 %. The manganese content in the light fraction varied from 1,7 to 2,5 %. Light fractions were represented by aggregates of quartz and calcite with manganese minerals. According to X-ray phase analysis, heavy fractions were mainly represented by minerals braunite, bixbyite, barite and hematite. [ABSTRACT FROM AUTHOR]

The present time is marked by the progress of technology related to energy storage. One of the promising priority energy storage devices is lithium-ion batteries (LIB), which have a high energy density and a low self-discharge level. To increase the charging capacity and general characteristics of LIB, researchers think about replacing one of the electrodes, in particular the anode, with more promising and cheaper materials. Of all the possible materials on the market, silicon (Si) is one of the most effective, promising, cheap, and widespread materials. In contrast to pure Si, composites based on it are becoming more widespread and are actively used as a material for LIB.

The material composition of kaolin raw materials with the content of Al2O3 - 17,21; SiO2 - 66,27; Fe2O3 - 0,51; TiO2 0,574 was studied. The main valuable minerals are kaolinite, halloysite, muscovite, quartz, rare marks of tourmaline, ilmenite. Particle size analysis of kaolin raw materials shows that the largest mass is represented by the size class (- 0,05+0 mm) - 43,08 %. 79,74 % of alumina with its content of 32,0 % is in the size class (- 0,05+0 mm), and it can be used as a raw material for further processing into alumina or as a universal filler for production of paper, rubber, cable, plastic and perfumery products. [ABSTRACT FROM AUTHOR]

Electrodeposition of copper and nickel from acidic solutions using a rotating cathode coated with liquid and solid gallium has been studied. Methods of nonferrous metals separation from the gallium coating of the cathode were determined. Electrodeposition on the liquid gallium coating was carried out at a temperature of 50 °C. Separation of metals from gallium was performed by alkaline treatment. On the solid gallium cathode coating, electrodeposition was performed at 25 °C. The metal precipitates were separated from the cathode after it was heated. When using cathode with hard gallium coating the reduction of electric power consumption for copper by 85 % and for nickel by 15 % was obtained. [ABSTRACT FROM AUTHOR]

The paper contains the laboratory study results for the flotation processing of gold-containing tailings with the use of the composite reagent (CF). The CF flotation reagent is a microemulsion from a composition of sodium butyl xanthate and reaflot. A gold-containing concentrate was obtained with a gold content of 6,7 g/t with a recovery of 59,71 % in the basic mode. The use of the CF composite flotation reagent increases the gold extraction into the gold-containing concentrate by 3,77 %, as compared with the main collector - sodium butyl xanthate. The consumption of CF flotation reagent is reduced by 20 %. [ABSTRACT FROM AUTHOR]

The work presents the results of studies on obtaining ferromanganese concentrate from technogenic manganese-containing raw materials with grain size less than 10 mm. It is found that the main valuable minerals of the feedstock are psilomelane, pyrolusite, bementite; among the rock-forming minerals, quartz and kaolinite, often saturated with finely dispersed iron compounds, prevail. Sieving and concentration of raw materials of - 10 + 5 mm and - 2 + 0,2 mm in two-chamber jigging machine with separation of two concentrates and tailingпs allowed to obtain a joint manganese concentrate with 35,1 % manganese content, 11,5 % iron content with 78,23 % manganese recovery. The obtained manganese concentrate is suitable for further metallurgical processing. [ABSTRACT FROM AUTHOR]