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The processing of low-grade polymetallic materials, such as copper–zinc, copper–lead–zinc, and poor arsenic-containing copper concentrates using hydrometallurgical methods is becoming increasingly important due to the depletion of rich and easily extracted mineral resources, as well as due to the need to reduce harmful emissions from metallurgy, especially given the high content of arsenic in ores. Ferric arsenates obtained through hydrothermal precipitation are the least soluble and most stable form of arsenic, which is essential for its disposal. This paper describes the investigation of the oxidation kinetics of As (III) ions to As (V) which is required for efficient purification of the resulting solutions and precipitation of low-solubility ferric arsenates. The effect of temperature (160–200 °C), the initial concentration of Fe (II) (3.6–89.5 mmol/dm3), Cu (II) (6.3–62.9 of mmol/dm3) and the oxygen pressure (0.2–0.5 MPa) on the oxidation efficiency of As (III) to As (V) was studied. As (III) oxidation in H3AsO-Fe2+-Cu2+-H2SO4 and H3AsO-Fe2+-H2SO4 systems was controlled by a chemical reaction with the apparent activation energy (Ea (≈84.3–86.3 kJ/mol)). The increase in the concentration of Fe (II) ions and addition of an external catalyst (Cu (II) ions) both have a positive effect on the process. When Cu (II) ions are introduced into the solution, their catalytic effect is confirmed by a decrease in the partial orders, Fe (II) ions concentration from 0.43 to 0.20, and the oxygen pressure from 0.95 to 0.69. The revealed catalytic effect is associated with a positive effect of Cu (II) ions on the oxidation of Fe (II) to Fe (III) ions, which further participate in As (III) oxidation. The semi-empirical equations describing the reaction rate under the studied conditions are written.
Kirill Karimov; Denis Rogozhnikov; Oleg Dizer; Maksim Tretiak; Sergey Mamyachenkov; Stanislav Naboichenko. Pressure Oxidation of Arsenic (III) Ions in the H3AsO3-Fe2+-Cu2+-H2SO4 System. Metals 2021, 11, 975 .
AMA StyleKirill Karimov, Denis Rogozhnikov, Oleg Dizer, Maksim Tretiak, Sergey Mamyachenkov, Stanislav Naboichenko. Pressure Oxidation of Arsenic (III) Ions in the H3AsO3-Fe2+-Cu2+-H2SO4 System. Metals. 2021; 11 (6):975.
Chicago/Turabian StyleKirill Karimov; Denis Rogozhnikov; Oleg Dizer; Maksim Tretiak; Sergey Mamyachenkov; Stanislav Naboichenko. 2021. "Pressure Oxidation of Arsenic (III) Ions in the H3AsO3-Fe2+-Cu2+-H2SO4 System." Metals 11, no. 6: 975.
At present, the processing of refractory gold–arsenic sulphide concentrates is becoming more relevant due to the depletion of rich crude ore reserves. In the process of the nitric acid leaching of arsenic sulphide minerals, solutions are formed containing 20–30 g/L of arsenic (III). Since market demand for arsenic compounds is limited, such solutions are traditionally converted into poorly soluble compounds. This paper describes the investigation of precipitating arsenic sulphide from nitric acid leaching solutions of refractory sulphide raw materials of nonferrous metals containing iron (III) ions using sodium hydrosulphide with a molar ratio of NaHS/As = 2.4–2.6, which is typical for pure model solutions without oxidants. The work studied the effect of temperature, the pH of the solution and the consumption of NaHS and seed crystal on this process. The highest degree of precipitation of arsenic (III) sulphide (95–99%) from nitric acid leaching solutions containing iron (III) ions without seed occurs with a pH from 1.8 to 2.0 and a NaHS/As molar ratio of 2.8. The introduction of seed crystal significantly improves the precipitation of arsenic (III) sulphide. An increase in seed crystal consumption from 0 to 34 g/L in solution promotes an increase in the degree of transition of arsenic to sediment from 36.2 to 98.1% at pH = 1. According to SEM/EDS and XRF sediment data, from the results of experiments on the effect of As2S3 seed crystal consumption, acidity and molar ratio of NaHS/As on the precipitation of arsenic (III) sulphide and the Fetotal/Fe2+ ratio in the final solution, it can be concluded that the addition of a seed accelerates the crystallisation of arsenic (III) sulphide by increasing the number of crystallisation centres; as a result, the deposition rate of As2S3 becomes higher. Since the oxidation rate of sulphide ions to elemental sulphur by iron (III) ions does not change significantly, the molar ratio of NaHS/As can be reduced to 2.25 to obtain a precipitate having a lower amount of elemental sulphur and a high arsenic content similar to that precipitated from pure model solutions.
Kirill Karimov; Denis Rogozhnikov; Evgeniy Kuzas; Oleg Dizer; Dmitry Golovkin; Maksim Tretiak. Deposition of Arsenic from Nitric Acid Leaching Solutions of Gold–Arsenic Sulphide Concentrates. Metals 2021, 11, 889 .
AMA StyleKirill Karimov, Denis Rogozhnikov, Evgeniy Kuzas, Oleg Dizer, Dmitry Golovkin, Maksim Tretiak. Deposition of Arsenic from Nitric Acid Leaching Solutions of Gold–Arsenic Sulphide Concentrates. Metals. 2021; 11 (6):889.
Chicago/Turabian StyleKirill Karimov; Denis Rogozhnikov; Evgeniy Kuzas; Oleg Dizer; Dmitry Golovkin; Maksim Tretiak. 2021. "Deposition of Arsenic from Nitric Acid Leaching Solutions of Gold–Arsenic Sulphide Concentrates." Metals 11, no. 6: 889.
This paper examines the possibility of using the hydrometallurgical process of nitric acid leaching to process the refractory sulphide concentrate of Akzhal. The study that looked at the structure and composition of this material confirmed that the studied material has a complex mineralogy due to dissemination of gold-bearing sulphides (mainly pyrite and arsenopyrite) in the gangue and their interpenetration, as well as the presence of finely dispersed gold (10 μm) in tight assemblage with the host minerals. A series of laboratory tests, as well as mathematical experimental design techniques, helped identify the most critical parameters governing the leaching efficiency. The following process parameters are recommended: nitric acid concentration — 5 mol/dm3, L/S = 5:1, = 1 h. A high recovery into solution can be achieved in the above conditions, %: >98 Fe; >96 As; >90 S. The authors propose to use atmospheric deposition of scorodite to dispose of leach liquors. This is achieved by means of staged neutralization until the concentration of arsenic in the liquor reaches 20 mg/dm3. Sorption techniques are applied to recover copper and zinc from leach liquors. Leach cakes are subjected to sorption cyanidation with the total recoveries of gold and silver of >94 and >64%, correspondingly. The nitrous gas recovery stage proved highly efficient — >90%. A series of pilot tests was carried out to verify the findings. Thus, the developed hydrometallurgical process was applied to the copper-bearing arsenic sulphide concentrate of Akzhal at the testing facility of KazGidroMed, a research centre for innovative technology. The tests enabled to conduct a feasibility study, which proved the proposed processing techniques to be efficient and feasible.This research study was funded by the Russian Science Foundation (Project no. 18-19-00186).The study of arsenic precipitation from leach liquor was funded by the Russian Foundation for Basic Research under the Research Project no. 18-38-00914\18.
D. A. Rogozhnikov; O. A. Dizer; K. A. Karimov; S. V. Zakharian; Karaganda KazGidroMed. Nitric acid leaching of the copper-bearing arsenic sulphide concentrate of Akzhal. Tsvetnye Metally 2020, 11 -17.
AMA StyleD. A. Rogozhnikov, O. A. Dizer, K. A. Karimov, S. V. Zakharian, Karaganda KazGidroMed. Nitric acid leaching of the copper-bearing arsenic sulphide concentrate of Akzhal. Tsvetnye Metally. 2020; ():11-17.
Chicago/Turabian StyleD. A. Rogozhnikov; O. A. Dizer; K. A. Karimov; S. V. Zakharian; Karaganda KazGidroMed. 2020. "Nitric acid leaching of the copper-bearing arsenic sulphide concentrate of Akzhal." Tsvetnye Metally , no. : 11-17.
Ammonia leaching is a promising method for processing low-grade copper ores, especially those containing large amounts of oxidized copper. In this paper, we study the effect of Si-containing minerals on the kinetics of Cu and Ag leaching from low-grade copper concentrates. The results of experiments on the pressure leaching of the initial copper concentrate in an ammonium/ammonium-carbonate solution with oxygen as an oxidizing agent are in good agreement with the shrinking core model in the intra-diffusion mode: in this case, the activation energies were 53.50 kJ/mol for Cu and 90.35 kJ/mol for Ag. Energy-dispersive X-ray spectroscopy analysis (EDX) analysis showed that reagent diffusion to Cu-bearing minerals can be limited by aluminosilicate minerals of the gangue. The recovery rate for copper and silver increases significantly after a preliminary alkaline desilication of the concentrate, and the new shrinking core model is the most adequate, showing that the process is limited by diffusion through the product layer and interfacial diffusion. The activation energy of the process increases to 86.76 kJ/mol for Cu and 92.15 kJ/mol for Ag. Using the time-to-a-given-fraction method, it has been shown that a high activation energy is required in the later stages of the process, when the most resistant sulfide minerals of copper and silver apparently remain.
Kirill Karimov; Andrei Shoppert; Denis Rogozhnikov; Evgeniy Kuzas; Semen Zakhar’Yan; Stanislav Naboichenko. Effect of Preliminary Alkali Desilication on Ammonia Pressure Leaching of Low-Grade Copper–Silver Concentrate. Metals 2020, 10, 812 .
AMA StyleKirill Karimov, Andrei Shoppert, Denis Rogozhnikov, Evgeniy Kuzas, Semen Zakhar’Yan, Stanislav Naboichenko. Effect of Preliminary Alkali Desilication on Ammonia Pressure Leaching of Low-Grade Copper–Silver Concentrate. Metals. 2020; 10 (6):812.
Chicago/Turabian StyleKirill Karimov; Andrei Shoppert; Denis Rogozhnikov; Evgeniy Kuzas; Semen Zakhar’Yan; Stanislav Naboichenko. 2020. "Effect of Preliminary Alkali Desilication on Ammonia Pressure Leaching of Low-Grade Copper–Silver Concentrate." Metals 10, no. 6: 812.
This article covers a hydrometallurgical method for processing of a gold-antimony flotation concentrate in alkaline sulfide solutions. Thermodynamic analysis of the reaction stibnite with sulfide sodium and sodium hydroxide was performed. The chemical and phase compositions of the investigated material, mainly represented by compounds of antimony, silicon, calcium, sulfur and iron are studied. Phase composition: quartz, stibnite, quicklime, pyrite, dolomite and arsenopyrite. The dependences of the influence of sulfide sodium and sodium hydroxide concentration, and the liquid to solid ratio on antimony extraction into solution were determined by methods of mathematical experiment planning. The calculated values of the determination coefficients testify to the adequacy of the chosen two-level model. The optimum parameters of the process were obtained: L/S ratio = 4,5; the nitric acid sulfide sodium concentration was 61.09 g/L; sodium hydroxide concentration was 16.47 g/
R.E. Rusalev; Denis Rogozhnikov; A.A. Koblik. Optimization of Alkaline Sulfide Leaching of Gold-Antimony Concentrates. Materials Science Forum 2020, 989, 525 -531.
AMA StyleR.E. Rusalev, Denis Rogozhnikov, A.A. Koblik. Optimization of Alkaline Sulfide Leaching of Gold-Antimony Concentrates. Materials Science Forum. 2020; 989 ():525-531.
Chicago/Turabian StyleR.E. Rusalev; Denis Rogozhnikov; A.A. Koblik. 2020. "Optimization of Alkaline Sulfide Leaching of Gold-Antimony Concentrates." Materials Science Forum 989, no. : 525-531.
This article describes the problems of deterioration of the quality of processed raw materials due to depletion of mineral resources. It is proposed to use nitric acid for the processing of complex refractory low-grade concentrates containing non-ferrous and noble metals. It was found that the studied concentrate contains: sphalerite (26.9 %), pyrite (22.0 %), chalcopyrite (19.9 %), silica (13.9 %), alumina (5.5 %), galena (1.7 %), oxidized forms of iron (Fe2O3) (12 %). Gold and silver are associated with sulfide minerals. Typical reactions of interaction of these minerals with nitric acid are considered. A sufficiently high thermodynamic probability of these reactions in a wide temperature range is established. With the use of mathematical methods, the optimal conditions of the process of nitric acid leaching are selected: the ratio of L:S = 5:1; the concentration of nitric acid 10 mol/L; the duration of the process is 60 minutes. In this case, the extraction of copper, zinc, iron and sulfur into the solution was 99.00 %, 99.84 % 98.60 %, 88.51 %, respectively.
Denis Rogozhnikov; Andrey A. Shoppert; L.M. Karimova. Investigating of Nitric Acid Leaching of High-Sulfur Copper Concentrate. Solid State Phenomena 2020, 299, 968 -973.
AMA StyleDenis Rogozhnikov, Andrey A. Shoppert, L.M. Karimova. Investigating of Nitric Acid Leaching of High-Sulfur Copper Concentrate. Solid State Phenomena. 2020; 299 ():968-973.
Chicago/Turabian StyleDenis Rogozhnikov; Andrey A. Shoppert; L.M. Karimova. 2020. "Investigating of Nitric Acid Leaching of High-Sulfur Copper Concentrate." Solid State Phenomena 299, no. : 968-973.
Low grade copper concentrate is a promising source for the future recovery of copper and other valuable components by nitric acid leaching, which leads to a formation of iron rich pregnant solution. In this study a method of producing of high-quality iron oxide from the pregnant solution by precipitation of jarosite with subsequent conversion of jarosite into magnetite under alkaline conditions in the presence of ferrous ions was explored. The degree of iron extraction was 87.4%, the copper content in the magnetite was 0.06% under the following optimal conditions of jarosite precipitation: precipitation time 6 h, initial pH 1.5, seed amount 60 g/L. However, to obtain this purity, the copper content in the pregnant solution should be less than 0.5 g/L, and as a seed, it is necessary to use a well-crystallized jarosite with a low content of impurities.
Andrey A. Shoppert; Denis Rogozhnikov; Y.E. Agapitov. Obtaining of High Quality Iron Oxide from Nitric Acid Leaching Solution. Solid State Phenomena 2020, 299, 1128 -1133.
AMA StyleAndrey A. Shoppert, Denis Rogozhnikov, Y.E. Agapitov. Obtaining of High Quality Iron Oxide from Nitric Acid Leaching Solution. Solid State Phenomena. 2020; 299 ():1128-1133.
Chicago/Turabian StyleAndrey A. Shoppert; Denis Rogozhnikov; Y.E. Agapitov. 2020. "Obtaining of High Quality Iron Oxide from Nitric Acid Leaching Solution." Solid State Phenomena 299, no. : 1128-1133.
The overall decrease in the quality of mineral raw materials, combined with the use of arsenic-containing ores, results in large amounts of various intermediate products containing this highly toxic element. The use of hydrometallurgical technologies for these materials is complicated by the formation of multicomponent solutions and the difficulty of separating copper from arsenic. Previously, for the selective separation of As from copper–arsenic intermediates a leaching method in the presence of Cu(II) ions was proposed. This paper describes the investigation of the kinetics of arsenic sulfide-containing materials leaching by copper sulfate solution. The cakes after leaching of arsenic trisulfide with a solution of copper sulfate were described using methods such as X-ray diffraction spectrometry (XRD), X-ray fluorescence spectrometry (XRF), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy analysis (EDS). The effect of temperature (70–90 °C), the initial concentration of CuSO4 (0.23–0.28 M) and the time on the As recovery into the solution was studied. The process temperature has the greatest effect on the kinetics, while an increase in copper concentration from 0.23 to 0.28 M effects an increase in As transfer into solution from 93.2% to 97.8% for 120 min of leaching. However, the shrinking core model that best fits the kinetic data suggests that the process occurs by the intra-diffusion mode with the average activation energy of 44.9 kJ/mol. Using the time-to-a-given-fraction kinetics analysis, it was determined that the leaching mechanism does not change during the reaction. The semi-empirical expression describing the reaction rate under the studied conditions can be written as follows: 1/3ln(1 − X) + [(1 − X) − 1/3 − 1] = 4560000Cu3.61e−44900/RT t.
Kirill A. Karimov; Denis A. Rogozhnikov; Evgeniy A. Kuzas; Andrei A. Shoppert. Leaching Kinetics of Arsenic Sulfide-Containing Materials by Copper Sulfate Solution. Metals 2019, 10, 7 .
AMA StyleKirill A. Karimov, Denis A. Rogozhnikov, Evgeniy A. Kuzas, Andrei A. Shoppert. Leaching Kinetics of Arsenic Sulfide-Containing Materials by Copper Sulfate Solution. Metals. 2019; 10 (1):7.
Chicago/Turabian StyleKirill A. Karimov; Denis A. Rogozhnikov; Evgeniy A. Kuzas; Andrei A. Shoppert. 2019. "Leaching Kinetics of Arsenic Sulfide-Containing Materials by Copper Sulfate Solution." Metals 10, no. 1: 7.
The processing of refractory gold-containing concentrates by hydrometallurgical methods is becoming increasingly important due to the depletion of rich and easily extracted mineral resources, as well as due to the need to reduce harmful emissions from metallurgy, especially given the high content of arsenic in the ores. This paper describes the investigation of the kinetics of HNO3 leaching of sulfide gold-containing concentrates of the Yenisei ridge (Yakutia, Russia). The effect of temperature (70–85 °C), the initial concentration of HNO3 (10–40%) and the content of sulfur in the concentrate (8.22–22.44%) on the iron recovery into the solution was studied. It has been shown that increasing the content of S in the concentrate from 8.22 to 22.44% leads to an average of 45% increase in the iron recovery across the entire range temperatures and concentrations of HNO3 per one hour of leaching. The leaching kinetics of the studied types of concentrates correlates well with the new shrinking core model, which indicates that the reaction is regulated by interfacial diffusion and diffusion through the product layer. Elemental S is found on the surface of the solid leach residue, as confirmed by XRD and SEM/EDS analysis. The apparent activation energy is 60.276 kJ/mol. The semi-empirical expression describing the reaction rate under the studied conditions can be written as follows: 1/3ln(1 − X) + [(1 − X)−1/3 − 1] = 87.811(HNO3)0.837(S)2.948e−60276/RT·t.
Denis A. Rogozhnikov; Andrei A. Shoppert; Oleg Dizer; Kirill A. Karimov; Rostislav E. Rusalev. Leaching Kinetics of Sulfides from Refractory Gold Concentrates by Nitric Acid. Metals 2019, 9, 465 .
AMA StyleDenis A. Rogozhnikov, Andrei A. Shoppert, Oleg Dizer, Kirill A. Karimov, Rostislav E. Rusalev. Leaching Kinetics of Sulfides from Refractory Gold Concentrates by Nitric Acid. Metals. 2019; 9 (4):465.
Chicago/Turabian StyleDenis A. Rogozhnikov; Andrei A. Shoppert; Oleg Dizer; Kirill A. Karimov; Rostislav E. Rusalev. 2019. "Leaching Kinetics of Sulfides from Refractory Gold Concentrates by Nitric Acid." Metals 9, no. 4: 465.
This article describes a method for the hydrochemical dissolution of a sulfide gold-bearing raw material from the Uderey’s deposit using nitric acid. The chemical and phase compositions of the studied material, mainly represented by compounds of silicon, sodium, arsenic, iron and sulfur, are investigated. Phase composition: pyrite, arsenopyrite, quartz, thenardite. The dependences of the influence of temperature, time, and the liquid to solid ratio on extracting the main components in the solution were determined by methods of mathematical experiment planning. The calculated values of the determination coefficients testify to the adequacy of the chosen two-level model. The optimum parameters of the process were obtained: L/S ratio = 8; the nitric acid concentration was 6 M; experiment duration was 75 minutes.
Oleg Dizer; Denis Rogozhnikov; Stanislav S. Naboichenko. Hydrochemical Investigation of Dissolving Sulfide Gold-Bearing Raw Material of Uderey Deposit. Materials Science Forum 2019, 946, 535 -540.
AMA StyleOleg Dizer, Denis Rogozhnikov, Stanislav S. Naboichenko. Hydrochemical Investigation of Dissolving Sulfide Gold-Bearing Raw Material of Uderey Deposit. Materials Science Forum. 2019; 946 ():535-540.
Chicago/Turabian StyleOleg Dizer; Denis Rogozhnikov; Stanislav S. Naboichenko. 2019. "Hydrochemical Investigation of Dissolving Sulfide Gold-Bearing Raw Material of Uderey Deposit." Materials Science Forum 946, no. : 535-540.
This article covers acid nitric leaching of Olympiada deposit refractory gold-bearing concentrate after alkaline leaching of stibnite. Thermodynamic analysis of the reaction pyrite and arsenopyrite with nitric acid chemical equations was performed. Equilibrium Eh-pH Pourbaix diagrams of heterogeneous systems studied, containing iron and arsenic were charted. Investigation of elemental and species analyses was maintained. The analysis of the main elements distribution and their combining over grains with the help of electron-probe microanalysis (EPMA) was investigated. It is established, that the material mainly consists of compounds of quartz, dolomite and calcite, as well as pyrite and arsenopyrite. Pre-treatment decarbonization operation of the feed material was proposed with the aim to reduce nitric acid consumption. The dependences of effects of the nitric acid concentration and L/S ratio on iron and arsenic dissolving were determined.
R.E. Rusalev; Denis Rogozhnikov; Stanislav S. Naboichenko. Nitric Acid Treatment of Olympiada Deposit Refractory Gold-Bearing Concentrate. Materials Science Forum 2019, 946, 541 -546.
AMA StyleR.E. Rusalev, Denis Rogozhnikov, Stanislav S. Naboichenko. Nitric Acid Treatment of Olympiada Deposit Refractory Gold-Bearing Concentrate. Materials Science Forum. 2019; 946 ():541-546.
Chicago/Turabian StyleR.E. Rusalev; Denis Rogozhnikov; Stanislav S. Naboichenko. 2019. "Nitric Acid Treatment of Olympiada Deposit Refractory Gold-Bearing Concentrate." Materials Science Forum 946, no. : 541-546.
This study investigates the use of red muds as adsorbents for As (V) removal. Red mud is a waste that contains a large amount of iron oxides and hydroxides, which are excellent adsorbents of arsenic, especially those possessing magnetic properties and a large specific surface area. The purpose of the experiments was to study the possibility of obtaining an effective adsorbent by the direct extraction of alumina from bauxite using the caustic alkali fusion method and to compare the arsenic removal effectiveness and other properties of these red muds with industrial samples. Red muds were described using methods such as X-ray diffraction spectrometry (XRD), X-ray fluorescence spectrometry (XRF), SEM, vibrating sample magnetometry (VSM), and the Brunauer–Emmett–Teller (BET) method. The main iron-containing phase of the red muds obtained by fusing bauxite with caustic alkali is maghemite, which has a large specific surface area. The specific surface area of the obtained samples varied in the range of 6.1–54.9 m2/g. Arsenic adsorption experiments were carried out using five different types of red muds: industrial Bayer, industrial sintering, and red mud obtained through bauxite alkali fusion at 300, 500, and 700 °C. The red muds obtained by fusing bauxite with caustic alkali at 300 and 500 °C had the highest effectiveness removing arsenic; their As(V) uptake capacity was over 30 mg/g.
Andrei A. Shoppert; Irina V. Loginova; Denis A. Rogozhnikov; Kirill A. Karimov; Leonid I. Chaikin. Increased As Adsorption on Maghemite-Containing Red Mud Prepared by the Alkali Fusion-Leaching Method. Minerals 2019, 9, 60 .
AMA StyleAndrei A. Shoppert, Irina V. Loginova, Denis A. Rogozhnikov, Kirill A. Karimov, Leonid I. Chaikin. Increased As Adsorption on Maghemite-Containing Red Mud Prepared by the Alkali Fusion-Leaching Method. Minerals. 2019; 9 (1):60.
Chicago/Turabian StyleAndrei A. Shoppert; Irina V. Loginova; Denis A. Rogozhnikov; Kirill A. Karimov; Leonid I. Chaikin. 2019. "Increased As Adsorption on Maghemite-Containing Red Mud Prepared by the Alkali Fusion-Leaching Method." Minerals 9, no. 1: 60.
This paper examines the most popular techniques of processing rebellious goldcontaining materials that cannot be cyanided using conventional techniques due to gold nanoparticles disseminated in the sulfide minerals. To loosen such rebellious concentrates, it is proposed to use nitric acid, which is an effective oxidizer and leaching agent. A gold sulphide concentrate from the Udereysk deposit was used in the study, which had been subjected to selective separation of antimony in alkaline sulphide solutions. The main gold-containing minerals in the concentrate include pyrite and arsenopyrite. The paper looks at the standard reactions between these minerals and nitric acid. The authors found a rather high thermodynamic probability of these reactions within a broad temperature range. Through building Pourbaix diagrams for arsenic and iron compounds in the considered heterogeneous systems, the authors demonstrate that in order to obtain the desired products from the interactions in view, the oxidation potential of the system should be maintained at the minimum level of 0.6 V. With the help of the mathematical methods of experiment design, the authors selected the nitric acid leaching parameters applicable to the test material: liquid-to-solid ratio = 8:1; nitric acid concentration — 6 mol/dm3; process duration — 75 minutes. The adequacy of the obtained data is confirmed by the calculated values of the determination coefficients, which were close to 100%. The extraction of iron and arsenic into the solution was around 97 and 92%, respectively. The obtained solid leaching residues, in which the concentration of gold can reach 100 g/t, are then sent to further extraction by conventional techniques. The leaching solutions containing iron and arsenic are neutralized and precipitate as low-solubility compounds. This research was funded by the Russian Science Foundation (Project No. 18-19- 00186). The study of the thermodynamics of the processes under consideration was funded under the Governmental Assignment No. 11.4797.2017/8.9.
D. A. Rogozhnikov; R. E. Rusalev; Oleg Dizer; S. S. Naboychenko. Nitric acid loosening of rebellious sulphide concentrates containing precious metals. Tsvetnye Metally 2018, 38 -44.
AMA StyleD. A. Rogozhnikov, R. E. Rusalev, Oleg Dizer, S. S. Naboychenko. Nitric acid loosening of rebellious sulphide concentrates containing precious metals. Tsvetnye Metally. 2018; ():38-44.
Chicago/Turabian StyleD. A. Rogozhnikov; R. E. Rusalev; Oleg Dizer; S. S. Naboychenko. 2018. "Nitric acid loosening of rebellious sulphide concentrates containing precious metals." Tsvetnye Metally , no. : 38-44.
Autoclave ammonia leaching of silver from low-grade copper concentrates is studied with use of Zhezkazgan concentrates of the following composition, %: 9.55 Cu, Fe 4.84, S 5.6, 27.03 Si, 109.6 g/ton Ag. According to X-ray phase analysis the main minerals present in the concentrate are, %: 29 quartz (SiO2 ), 33 plagioclase ((Ca, Na)(Al, Si)AlSi2O6 ), 16 mica, 10 chalcocite (Cu2S), 2 chalcopyrite (CuFeS2 ), and 7 pyrite (FeS2 ). It is shown that during ore processing in which gold and silver are in close association with sulfide minerals, precious metals are not extracted by cyaniding even after ultrafine grinding. The proportion of such persistent raw materials is more than 30% of the total ore reserves containing precious metals in the world. Use of the most common technologies of autoclave sulphuric acid and neutral leaching for quantitative oxidation of gold and silver containing sulphides in this case is limited due to the formation of argentojarosite, inert with respect to the cyanide ion. In order to avoid its formation and to increase the degree of leaching silver directly at the autoclave stage, its extraction in ammonia is investigated. With direct autoclave leaching copper extraction into solution is 93–97%, while silver extraction is not observed in some experiments, which may be due to the sorption activity of aluminum and silicon compounds present in the concentrate. Preliminary mechanical activation and surface resynthesis have a favorable effect on recovery rates of copper and silver in solution. An additional operation of concentrate silica removal provides extraction of 97% copper and 83% silver into solution with [NH4OH] = 7 mole/dm3, L:S = 10:1, τ = 3 h, pO2 = 0.6 MPa, t = 140°С.
K. A. Karimov; Denis Rogozhnikov; S. S. Naboichenko; L. M. Karimova; S. V. Zakhar’Yan. Autoclave Ammonia Leaching of Silver from Low-Grade Copper Concentrates. Metallurgist 2018, 62, 783 -789.
AMA StyleK. A. Karimov, Denis Rogozhnikov, S. S. Naboichenko, L. M. Karimova, S. V. Zakhar’Yan. Autoclave Ammonia Leaching of Silver from Low-Grade Copper Concentrates. Metallurgist. 2018; 62 (7-8):783-789.
Chicago/Turabian StyleK. A. Karimov; Denis Rogozhnikov; S. S. Naboichenko; L. M. Karimova; S. V. Zakhar’Yan. 2018. "Autoclave Ammonia Leaching of Silver from Low-Grade Copper Concentrates." Metallurgist 62, no. 7-8: 783-789.
This paper details the hydrometallurgical method of processing of refractory gold antimony flotation concentrate. Investigation of feed material has been occurred. Mineralogical analyses (XRD, SEM-EDS) and chemical analyses of the concentrate have been studied. Mainly, the material consists of compounds of antimony, silicon, calcium, sulfur and iron. The main phases are quartz, stibnite, calcium carbonate and ankerite, pyrite and arsenopyrite have been found as well. The feature of antimonite’s dissolving in alkaline solutions has been reviewed. The dependences of effects of the temperature, time, L/S ratio and NaOH concentration on the antimony and sulfur extraction from the feed flotation concentrate have been determined. During alkaline sulphide leaching of the starting material several physicochemical characteristics of gold dissolution have been identified. Agitated cyanide gold leaching test of the pre-treated cake was conducted. Gold recovery was 32.2%. The obtained low indexes of gold recovery are based on cyanidation. A nitric acid leaching of disantimonied cake was proposed.
R.E. Rusalev; Denis Rogozhnikov; S.S. Naboichenko. Investigation of Complex Treatment of the Gold-Bearing Antimony Flotation Concentrate. Solid State Phenomena 2018, 284, 863 -869.
AMA StyleR.E. Rusalev, Denis Rogozhnikov, S.S. Naboichenko. Investigation of Complex Treatment of the Gold-Bearing Antimony Flotation Concentrate. Solid State Phenomena. 2018; 284 ():863-869.
Chicago/Turabian StyleR.E. Rusalev; Denis Rogozhnikov; S.S. Naboichenko. 2018. "Investigation of Complex Treatment of the Gold-Bearing Antimony Flotation Concentrate." Solid State Phenomena 284, no. : 863-869.
Sulfatization roasting of refractory copper-zinc sulphide raw material is studied. Test material chemical and phase compositions are examined. Thermodynamic calculations of possible sulfatization reactions are performed. Phase transformations, mechanisms of decomposition, and oxidation of sulphide minerals are studied using thermogravimetric and differential-thermal analyses. Equilibrium distribution of the system components during copper-zinc sulphide raw material roasting is modelled using an HSC Chemistry 6.0 computer program. Optimum conditions are established for roasting in which copper and zinc sulphide minerals are converted into sulphate form and iron is converted into oxide. Consolidated tests of sulfatizing roasting of copper-zinc sulphide middlings confirm results of experimental studies.
D. A. Rogozhnikov; D. L. Tropnikov; S. V. Mamyachenkov; Oleg Dizer. Improvement of Sulfatizing Roasting of Refractory Copper-Zinc Sulphide Raw Material. Metallurgist 2017, 61, 703 -709.
AMA StyleD. A. Rogozhnikov, D. L. Tropnikov, S. V. Mamyachenkov, Oleg Dizer. Improvement of Sulfatizing Roasting of Refractory Copper-Zinc Sulphide Raw Material. Metallurgist. 2017; 61 (7-8):703-709.
Chicago/Turabian StyleD. A. Rogozhnikov; D. L. Tropnikov; S. V. Mamyachenkov; Oleg Dizer. 2017. "Improvement of Sulfatizing Roasting of Refractory Copper-Zinc Sulphide Raw Material." Metallurgist 61, no. 7-8: 703-709.
Thermodynamic and kinetic features studies of polymetallic sulfide industrial waste nitric acid leaching were carried out. Elemental and phase composition of investigated raw material were studied with X-ray diffraction and electron microscopy methods. Calculations of the Gibbs energy change for the likely reactions of sulfide minerals with nitric acid were performed. In order to determine the most probable conditions of the sulfide industrial waste leaching in nitric acid, as well as the mutual influence of the produced pulp components on the performance of the process, the kinetics evaluation of multicomponent sulfide industrial waste in a nitric medium was studied using mathematical methods.
Rogozhnikov D.A.; Dizer O.A.; Shoppert A.A.. Research of Polymetallic Sulfide Industrial Waste Nitric Acid Treatment. KnE Materials Science 2017, 2, 174 .
AMA StyleRogozhnikov D.A., Dizer O.A., Shoppert A.A.. Research of Polymetallic Sulfide Industrial Waste Nitric Acid Treatment. KnE Materials Science. 2017; 2 (2):174.
Chicago/Turabian StyleRogozhnikov D.A.; Dizer O.A.; Shoppert A.A.. 2017. "Research of Polymetallic Sulfide Industrial Waste Nitric Acid Treatment." KnE Materials Science 2, no. 2: 174.
The purpose of this work is the kinetic evaluation of reactions occurring during nitric acid leaching of pollymetallic sulfide middlings, for the most complete translation of copper, zinc and sulfur in solution and concentration of precious metals in residue. Methodology is pollymetallic sulfide middlings nitric acid leaching kinetics were studied using mathematical methods such as the experimental data numerical differentiation. Relevance/value is the main sulfide minerals kinetic characteristics were obtained for the studied materials, including the rate of the process, order of reaction, the rate constant for the forward and reverse reaction. Findings are the rate of the process is limited by kinetics. The calculated values of kinetic parameters showed that the process kinetics are influenced by such factors as the nature of leachable sulfide, nitric acid concentration, the surface area of the solid sulfide, the system approaches equilibrium at saturation of the liquid phase reaction products.
Denis Rogozhnikov; B.V. Kolmachikhin. Polymetallic Ore Concentration Middlings Nitric Acid Leaching Kinetics. Solid State Phenomena 2017, 265, 1065 -1070.
AMA StyleDenis Rogozhnikov, B.V. Kolmachikhin. Polymetallic Ore Concentration Middlings Nitric Acid Leaching Kinetics. Solid State Phenomena. 2017; 265 ():1065-1070.
Chicago/Turabian StyleDenis Rogozhnikov; B.V. Kolmachikhin. 2017. "Polymetallic Ore Concentration Middlings Nitric Acid Leaching Kinetics." Solid State Phenomena 265, no. : 1065-1070.
Results of an analysis of thermodynamic characteristic and the investigation into kinetic regularities of leaching a new type of sulfated copper–zinc middlings formed with the removal of sulfide materials that cannot be effectively selected by flotation are presented. When analyzing the kinetic curves, it is established that the reaction rate abruptly differs between the initial time period (30 min) and the subsequent period at any acid concentration in a range of 0–20 g/dm3. In the initial instant, the rate is controlled only by the external diffusion, while after 30 min of the process, the kinetic obstacles start to manifest themselves. Reaction orders of cinder leaching are determined to be as follows: 1.0 ± 0.1 for copper, 0.87 ± 0.1 for zinc, and 0.56 ± 0.1 for iron. A calculation of the apparent rate constant of the leaching reaction showed its weak temperature dependence, which correlates well with the thermodynamic analysis data.
A. M. Panshin; S. V. Mamyachenkov; D. L. Tropnikov; O. S. Anisimova; D. A. Rogozhnikov. Investigation into regularities of leaching sulfated cinders of roasting copper–zinc middlings. Russian Journal of Non-Ferrous Metals 2017, 58, 345 -350.
AMA StyleA. M. Panshin, S. V. Mamyachenkov, D. L. Tropnikov, O. S. Anisimova, D. A. Rogozhnikov. Investigation into regularities of leaching sulfated cinders of roasting copper–zinc middlings. Russian Journal of Non-Ferrous Metals. 2017; 58 (4):345-350.
Chicago/Turabian StyleA. M. Panshin; S. V. Mamyachenkov; D. L. Tropnikov; O. S. Anisimova; D. A. Rogozhnikov. 2017. "Investigation into regularities of leaching sulfated cinders of roasting copper–zinc middlings." Russian Journal of Non-Ferrous Metals 58, no. 4: 345-350.
Nitride leaching of copper-zinc sulfide middlings that are difficult to concentrate is studied with the aim of clarifying and supplementing results obtained previously. It is shown that organization of two-stage countercurrent leaching makes it possible to reduce the concentration of nitrate ions within leaching solution, to increase the degree of nitric acid regeneration, and to increase copper and zinc concentration in solution and precious metals in the residue.
D. A. Rogozhnikov; S. V. Mamyachenkov; O. S. Anisimova. Nitric Acid Leaching of Copper-Zinc Sulfide Middlings. Metallurgist 2016, 60, 229 -233.
AMA StyleD. A. Rogozhnikov, S. V. Mamyachenkov, O. S. Anisimova. Nitric Acid Leaching of Copper-Zinc Sulfide Middlings. Metallurgist. 2016; 60 (1):229-233.
Chicago/Turabian StyleD. A. Rogozhnikov; S. V. Mamyachenkov; O. S. Anisimova. 2016. "Nitric Acid Leaching of Copper-Zinc Sulfide Middlings." Metallurgist 60, no. 1: 229-233.