Metallurgy
Abdykirova G.Zh., Tanekeyeva M.Sh., Tojlanbaj G.A., Sydykov A.E.The prospects of obtaining manganese concentrate from secondary raw material
Title | The prospects of obtaining manganese concentrate from secondary raw material |
Authors | Abdykirova G.Zh., Tanekeyeva M.Sh., Tojlanbaj G.A., Sydykov A.E. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, lab of flotation reagents and benefication, Almaty Abdykirova G.Zh., Cand Tech.Sci, leading scientific worker Tanekeyeva M.Sh., scientific worker, This email address is being protected from spambots. You need JavaScript enabled to view it.”>maira.shaimardan@gmail.com Tojlanbaj G.A., leading engineer Sydykov A.E., engineer |
Summary | The method of chemical beneficiation of manganese-containing secondary raw material to produce a high-quality concentrate of non-phosphorus oxide using a non-fired scheme was developed. The first step of the method is a hydro-chemical treatment of grinded slime using nitrate leaching to transfer manganese into solution; the second is purification of solution from iron, phosphorus, silica and sulfur impurities; ballast salts; followed by precipitation of manganese from the solution in the form of an oxide concentrate. The optimum conditions for leaching the slime by using nitric acid and sodium chloride are: concentration of HNO3 – 700 g/dm3, temperature – 90 °C, the ratio S:L = 1:2 and duration – 2 hours. The main parameters of the precipitation of manganese from leaching solution of ammonium hydroxide with stirring and aeration by air were determined: pH 9,5-10,0; temperature – 90 °C, duration – 60 minutes, the extraction of manganese – 95 %. During the slime processing, chemical precipitation was used to obtain experimental sample of manganese concentrate containing 65 % manganese and 0,002 % phosphorus that fully meets the requirements of steel industry. According to an X-ray analysis, manganese concentrate has a crystal structure of hausmannite Mn3O4. The proposed technological scheme is simple to implement, an environmentally friendly and allows reaching the following characteristics: an open-ended extraction of manganese from slime to concentrate – 77-78 %; the manganese content in the productive solution – 41-43 g/dm3; the degree of dephosphorization of solution – 99 %. Obtained manganese concentrates have a high manganese content and low phosphorus content and suitable for smelting all types of ferroalloys. |
Key words | manganese-containing slime, chemical concentration, leaching, nitrate solution, purification, precipitation, thermal decomposition, manganese concentrate. |
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Bochevskaya E.G., Abisheva Z.S., Karshigina Z.B., Turdalieva B.D., Kvyatkovskaya M.N.Behavior of rare earth elements at the nitrate acid leaching of slag from phosphorus production
Title | Behavior of rare earth elements at the nitrate acid leaching of slag from phosphorus production |
Authors | Bochevskaya E.G., Abisheva Z.S., Karshigina Z.B., Turdalieva B.D., Kvyatkovskaya M.N. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, lab. of rare and scattered elements, Almaty Bochevskaya E.G., Cand Tech.Sci, leading scientific worker, elena_bochevskaya@ mail.ru Abisheva Z.S., Dr. Tech.Sci, Corresponding member of RK NAS, Director of Mines-Metallurgical Institute named after O.Bajkonurov of KazNRTU named after K.I.Satpaev Karshigina Z.B., junior scientific worker Turdalieva B.D., undergraduate for master’s degree Lab of physical methods of analysis Kvyatkovskaya M.N., scientific worker |
Summary | The article presents the results of determining the mode of the leaching process of rare earth metals (REMs) during the nitric acid decomposition of slag from phosphorus production. According to scientific and technical publications, phosphorus containing raw materials such as apatite ores, concentrates, or intermediate products of their processing are used for production of rare-earth metals. Processing by nitric acid is the most suitable for phosphorus slag leaching. An experimental data was analyzed by using method of “initial rate” – the equation of formal kinetics and criterion-Pilling-Bedford’s (zP-B). It was shown that REMs in the slag is presented by carbonate-apatite Ca10[PO4]6CO3 or rare earth apatite and compound La2S3. The choice of the nitric acid concentration for slag leaching with a maximum transfer REM into solution was substantiated. The dependence of the ΣREMs recovery into solution on mixing intensity and duration was studied. By applying graphic method, rates of interaction of the REM-containing compounds with a solution of nitric acid, depending on the temperature of leaching were calculated. It is shown that an increase in temperature from 60 to 90 °C virtually have no effect on the recovery of ΣREMs into solution (~ 97 – 98%). By applying the logarithmic dependence lgw – 1/T, the value of apparent activation energy ~ 2.4 kJ/mol was determined. The phase composition of cakes was studied by using X-ray and infrared spectroscopic analysis. It was determined that during the process of slag leaching by solution of nitric acid, gel of silicic acid – nSiO2∙mH2O is being formed. The silica gel is conducive to covering slag particles and prevents access to them of nitric acid solution. The obtained experimental data represents that the leaching process takes place in internal diffusion area. |
Key words | phosphorus slag, leaching, rare-earth metals, recovery, cake, rate, activation energy |
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Kovzalenko V.A., Sadykov N.M-K., Manapov I.Zh.Processing of kaolin clays by fluoride method with obtaining compounds of silicon
Title | Processing of kaolin clays by fluoride method with obtaining compounds of silicon |
Authors | Kovzalenko V.A., Sadykov N.M-K., Manapov I.Zh. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, lab of alumina and aluminium, Almaty Kovzalenko V.A., Cand Tech.Sci, leading scientific worker, kovza40@mail.ru Sadykov N.M-K., scientific worker Manapov I.Zh, undergraduate for master’s degree |
Summary | Processing of kaolin by fluoride method with obtaining compounds of silicon – ammonium hexafluorosilicate and amorphous silica is investigated. Kaolin clay sintering with fluoride – ammonium hydrogen difluoride with a separation of charge to the gas phase in the form of ammonium hexafluorosilicate and nonvolatile solid fluorides was carried out. Sintering is realized in a high-temperature electric furnace with reactor communicates with desublimator for collecting, cooling and condensation of the gaseous phase. The thermodynamic parameters of possible reactions and changes of the Gibbs energy were analyzed. An analysis showed that in the process of sintering the main minerals of the kaolinite clays interact with NH4HF2, and all of the reactions are exothermic. The optimum technological conditions of the fluorination process: temperature stepped rising from 230 up to 550 oC, time 240 minutes, ratio of kaolin clay to the ammonium bifluoride 1 : 2 were determined. Extraction of the silicon into the gas phase with forming ammonium hexafluorosilicate (NH4)2SiF6 was – 98,6 %. At reaction of dissolved ammonium hexafluorosilicate with a concentrated solution of ammonia was burned at temperature 800 °C. At that form of amorphous silica and water communication is changed from a strong chemical and coordination to the weak adsorption. Burned amorphous silica is amorphous single phase – β-SiO2 – cristobalite dispersed. By the method of Brunauer – Emmett – Teller specific surface is determined and calculated the size of particles of amorphous silica. As the work result carbon white of BS-120 brand was obtained. |
Key words | kaolinite clay, ammonium difluoride, caking, ammonium hexafluorosilicate, ammonia solution, amorphous silica, carbon white. |
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Naimanbayev M.A., Lokhova N.G., Baltabekova Zh.A., Abisheva A.E., Maldybaev G.K.Production of titanium dioxide at processing titaniferous magnetite concentrate of of Tymlaj deposit
Title | Production of titanium dioxide at processing titaniferous magnetite concentrate of of Tymlaj deposit |
Authors | Naimanbayev M.A., Lokhova N.G., Baltabekova Zh.A., Abisheva A.E., Maldybaev G.K. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, lab of titanium and rare refractory metals, Almaty Naimanbayev M.A., Cand. Tech. Sci., head of lab., madali_2011@inbox.ru Lokhova N.G., senior scientific worker Baltabekova Zh.A., scientific worker Abisheva A.E., junior scientific worker Maldybaev G.K. doctoral student KazNRTU, leading engineer |
Summary | Deficit of ilmenite raw materials in the Republic of Kazakhstan for titanium slag melting challenges the search of alternative titanium-containing raw materials, titaniferous magnetites in particular. Tymlaj deposit in the South-Eastern part of Chu-Ili watershed is of particular interest, within the Karasaj ore unit with iron content of 30,4 and titanium dioxide – 10 %. And after beneficiation titaniferous magnetite concentrate contains Fe – 52,4; TiO2 – 16,06 %. Titanium slag obtained at electric smelting of titaniferous magnetite concentrate from Tymlaj deposit was used for the studies. Slag produced at ore-thermal smelting of titaniferous magnetite consists mainly of aluminum silicates and sodium silicotitanates, magnesium and calcium titanates, titanium dioxide and lower titanium oxides. In this regard, chemical beneficiation is the main task at solving the problem of low titanium slags processing. Following operations were carried out to improve titanium slag quality: slag sintering with sodium hydroxide; cake leaching with water to remove water-soluble impurities. To reduce the number of operations impurities leaching with hydrochloric acid was combined with pyrohydrolysis of titanic acid; desiliconization of produced rutile concentrate (85 % TiO2, 7,66 % SiO2) was carried out by sodium hydroxide solution treatment. Finally conditional rutile concentrate with titanium dioxide content 91-92 and silica – 1,7-2,0 % was produced. Based on the results of conducted studies the process flow diagram for saleable rutile concentrate obtaining from low-titanium-containing slag was offered. |
Key words | titaniferous magnetite, titanium slag, chemical beneficiation, desiliconization, rutile |
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Sarsenbay G., Kovzalenko V.A., Abdulvaliev R.A., Sadykov N. M.-K., Imangalieva L.M.Alkaline solution concentration influence on the process of leaching of clay fraction of Alekseev deposit's kaolinite clay
Title | Alkaline solution concentration influence on the process of leaching of clay fraction of Alekseev deposit’s kaolinite clay |
Authors | Sarsenbay G., Kovzalenko V.A., Abdulvaliev R.A., Sadykov N. M.-K., Imangalieva L.M. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, lab of alumina and aluminium, Almaty Sarsenbay G., Cand Tech.Sci, senior scientific worker, mer-pa@mail.ru Kovzalenko V.A., Cand Tech.Sci, leading scientific worker Abdulvaliev R.A., Cand. Tech. Sci., head of lab. Sadykov N. M.-K., scientific worker Imangalieva L.M., leading engineer |
Summary | Results of the physicochemical studies of kaolinite clay from Alekseev deposit indicates that this clay belongs to the group of sandy, and is useful for preparing silicate products and alumina concentrate. Separation of kaolinite clay to obtain sand and clay fractions carried out by elutriation. The sand fraction comprises a monophase of quartz. At the study of enriched clay fraction was found that it includes the following phases, %: kaolinite – 63.2; quartz – 21.6; muscovite – 15.3. The effect of the concentration of sodium hydroxide ([Na2O] 30 – 190 g/dm3) to leaching the clay fraction were studied. The process was carried out at a temperature of 90 °C, duration 60 minutes and a ratio L : S = 10: 1. As a result of leaching of the clay fraction of kaolin clay it was found that the extraction of silica and alumina into the solution is relatively small. In this connection, calcining of the clay fraction was carried out at a temperature 1050 °C and duration 90 min. As a result of calcining the clay fraction decomposed into quartz – 75.3 %, mullite – 23.7 % and cristobalite – 0.9 %. At that, according to the results of X-ray diffraction, the main phase of clay – kaolinite (Al2 (Si2O5) (OH) 4) transforms to the active form of silicon oxide, soluble in an alkaline solution and the aluminum oxide stabilizes into reaction passive mullite (3Al2O3∙2SiO2). Analysis of the solutions and cakes after leaching of calcined clay fraction showed that selective extraction of silicon oxide SiO2 into the solution of sodium hydroxide and concentration of aluminum oxide Al2O3 in cake occurs at the Na2O concentrations 110 g/dm3. Thus, leaching of the clay fraction without preliminary calcining is inexpedient for selective extraction of silica. |
Key words | kaolinite clay, silicon oxide, alumina, silica, sodium hydroxide solution, concentration, extraction, leaching, calcining. |
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Smirnov K.M., Krylova O.K., Zaytseva A.V., Zyukova G.A.Recycling of silicomanganese production's waste with obtaining of manganese-containing solutions for produce of high-quality manganese concentrates
Title | Recycling of silicomanganese production’s waste with obtaining of manganese-containing solutions for produce of high-quality manganese concentrates |
Authors | Smirnov K.M., Krylova O.K., Zaytseva A.V., Zyukova G.A. |
Author´s information | Scientific Research Institute for Chemical Technology, State corporation “Rosatom”, Department for Complex processing of mineral raw materials, lab. of Leaching technology and separation processes, Moscow, Russia Smirnov K.M., Cand. Tech. Sci., division head, smirnov@vniiht.ru Krylova O.K., head of lab Zaytseva A.V., senior scientific worker Zyukova G.A. , senior scientific worker |
Summary | Adaptation laboratory researches on hydrometallurgical processing of filter dusts from gas dry purification at the silicomanganese production to produce manganese commodity products were conducted. The possibility of using different methods of manganese ore material leaching for the processing of industrial waste was shown. Dry gas cleaning filter dust by mineral composition can be attributed to a mixed oxide-manganese silicate type of material. Optimum conditions for the preparation of manganese-containing solutions of the dusts from gas treatment are found: sulfuric acid reductive leaching at 80 0C; the ratio S : L = 1 : 3; the duration of 2 hours; using iron sulfate (II) as a reducing agent, and subsequent neutralizing by lime milk and filtration at pressure. Contents of the main component and impurities in the manganese solution were, g/dm3: 64-67 Mn; 1.0-2.0 Fetotal; 6.9-7.6 Zn; 0,7 Ca; 0,0002 Cu; <0,01 Ni; 0,001 P; 0,03 SiO2. Solutions have satisfactory contents of copper, nickel, phosphorus and iron, but a high content of zinc. Zinc recovery rate is ~ 30 %. Further purification of leached solutions was studied by using liquid silica glass. The mode at which the degree of zinc precipitation 82 % was chosen. Zinc residual content in the solution decreased up to 1,2-1,5 г/дм3, and in the obtained salts (the carbonate and the basic carbonate of manganese) – to 1,0-1,2 %. Thus, as a result of improvement of technology for processing of the dusts from dry gas purification zinc content in manganese commodity products decreased 5-6 times. |
Key words | dry gas cleaning dust, silicomanganese production wastes, manganese solutions, rare earth metals impurity, degree of precipitation, zinc, liquid silica glass. |
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Ul'tarakova A.A., Naimanbayev M.A., Onayev M.I., Maldybayev G.K., Alzhanbayeva N.Sh.Determination of optimum conditions for reductive roasting and magnetic separation of titaniferous magnetites with low titanium content
Title | Determination of optimum conditions for reductive roasting and magnetic separation of titaniferous magnetites with low titanium content |
Authors | Ul’tarakova A.A., Naimanbayev M.A., Onayev M.I., Maldybayev G.K., Alzhanbayeva N.Sh. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, lab of titanium and rare refractory metals, Almaty Ul’tarakova A.A., Cand Tech.Sci, senior scientific worker, ult.alma@mail.ru Naimanbayev M.A., Cand Tech.Sci, head of lab. Onayev M.I., Cand Tech.Sci, leading scientific worker Maldybayev G.K., doctoral student, leading engineer Alzhanbayeva N.Sh. , leading engineer |
Summary | The main stages of technology for complex processing of titaniferous magnetites of deposit Masalskij are reduction sintering and wet magnetic separation to maximize of iron and vanadium transfer into metallic fraction. Shubarkul coal and anthracite were used as a solid reductant. Experiments on solid phase reductive roasting of concentrate of Masalskij titaniferous magnetite with Shubarkul coal were carried out at temperatures from 600 to 1400 °C. Then wet magnetic separation of cinder of class -0.1 mm at magnetic field strength 200 Oe was conducted. With increase of temperature during sintering the metallization degree increases from 2.4 to 93.0 %. Starting from 1200 °C metal fraction +0.1 mm was formed. Among fraction +0.1 mm metal particles with size 1-2 mm were revealed at temperature 1300 °C. To compare the parameters of reductive roasting of the titaniferous magnetite concentrate (TMC) with different types of reductants next experiments were conducted with anthracite as reductant in the temperature range from 700 to 1400 °C. After cinders grinding to class -0.1 mm they were subjected to wet magnetic separation at magnetic field strength 200 Oe. With increase of sintering temperature the metallization degree increases from 1.4 up to 95.6 %. Starting from 1200 °C metal fraction +0.1 mm was formed. Among fraction +0.1 mm metal particles with size 1 mm were formed at temperature 1400 °C. Experiments on TMC reductive roasting were carried out in same conditions by using Shubarkul coal with addition of soda in the temperature range 600-1400 °C. Sinters of class -0.1 mm were subjected to wet magnetic separation. With increasing sintering temperature from 600 up to 1400 °C degree of iron metallization increases from 3.8 up to 91.4 %. Temperature mode for reductive roasting of Masalskij TMC: heating to 900 °C and holding for 60 min, then raising the temperature up to 1450 ° C and holding for 20 min. The optimum composition of the charge for sintering titaniferous magnetite concentrate, %: 77.2 TMC; 17.2 anthracite; 4 soda and 1.6 binder. At that a metallization degree of iron is 98%. Optimal parameters of magnetic separation for efficient division of fractions is the magnetic field strength of 200 Oe. |
Key words | titanium magnetite, metallic iron, vanadium, reduction roasting, cinder, magnetic separation |
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Physical-chemical studies
Burabayeva N.M., Volodin V.N., Trebukhov S.A., Ersajynova A.A.Thermodynamics of formation and evaporation of selenium - sulfur melts
Title | Thermodynamics of formation and evaporation of selenium – sulfur melts |
Authors | Burabayeva N.M., Volodin V.N., Trebukhov S.A., Ersajynova A.A. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, lab of vacuum processes, Almaty Burabayeva N.M., Cand. Tech. Sci, scientific worker, Nuri_eng@mail.ru Volodin V.N., Dr. Tech.Sci., Dr. Phys. Math. Sci. chief scientific worker Trebukhov S.A., Cand. Tech. Sci., head of lab. Ersajynova A.A., undergraduate for master’s degree |
Summary | On the basis of temperature and concentration dependences of partial pressure of saturated vapor of components of selenium-sulfur system and their activities in the liquid condensed phase thermodynamic functions of mixing and evaporation of the alloys are determined. The thermodynamic activity of sulfur in Se-S system is obtained on the basis of the value of a partial vapor pressure as ratio of the value of vapor pressure over an alloy to value of vapor pressure over pure component. The system is characterized by a strong negative deviation from the idealness. Partial and integral mixing enthalpy changes are negative in all concentration range, that is, the formation of liquid solutions of selenium-sulfur comes with heat elimination. The minimum on the curve of mixing integral enthalpy change is -9.67 kJ/mol. Change of entropy of alloys formation has positive and insignificant value, a maximum corresponds to 2,01 J/(mol•К). Extremum on the curve corresponds to the cumulative change of the Se3S7composition, which is consistent with an earlier data obtained by mass spectrometric studies. The concentration dependences of the enthalpy and entropy of vaporization have a complicated shape that is apparently conditioned by the variety of the molecular composition of liquid solutions and the vapor phase. Determined partial thermodynamic functions of formation and evaporation of melts of selenium-sulfur system and integrated constants can be used in thermodynamic calculations, and also to enrich physicochemical and reference data base of thermodynamic quantities. |
Key words | sulfur, selenium, vapor pressure, activity, entropy, enthalpy, partial functions, integrated functions, mixture, evaporation. |
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Zlobina E.V., Pak L.O.The overall extraction of scandium and rare earth metals by binary extraction
Title | The overall extraction of scandium and rare earth metals by binary extraction |
Authors | Zlobina E.V., Pak L.O. |
Author´s information | Al-Farabi Kazakh National University, Faculty of analytical, colloidal chemistry and technology of rare elements, Almaty Zlobina E.V., Cand. Chem. Sci, docent, senior scientific worker, zeva65@mail.ru “Center of Earth sciences, metallurgy and ore benefication” JSC, chemical analytical lab. Almaty Pak L.O., мaster of chemistry, junior scientific worker |
Summary | In the technology of rare earth metals (REM) obtaining main methods of separation and concentration are extraction and precipitation. The use of binary extractants can increase the distribution and separation coefficients, simplify of the reextraction. In this work binary extractant – di-2-ethyl-hexyl-phosphate of three-alkyl-benzyl-ammonium (TABAH-D2EHPA) was synthesized. Preparation of extractant was confirmed by the study of the extraction equilibria in the system “strong mineral acid – binary extractant”. The regularities of binary extraction of scandium, yttrium, thorium and rare earth elements were studied depending on various factors: concentration of nitric acid, nature of the anion and concomitant metals. Extraction of scandium, thorium, yttrium, rare-earth metals by binary extractant TABAH-D2EHPA does not depend on the concentration of nitric acid in the range 0,01-2 M. The degree of extraction from model solutions, %: thorium and scandium is more than 95; Yb is 58; Er, Y – 30; Tb, La, Gd, Eu – 18. The simultaneous presence of metals does not effect on the degree of extraction of scandium, yttrium and rare earth elements. Metals extraction by binary extractant increase in the following order: La, Eu, Gd |
Key words | binary extraction, rare earth elements, scandium, di-2-ethyl-hexyl-phosphoric acid, three-alkyl-benzyl-ammonium chloride. |
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Materials technology
Uskenbayeva A.M., Shamel'khanova N.A., Volochko A.T.Spectral researches of carbonic nanostructures used as cast iron modifiers
Title | Spectral researches of carbonic nanostructures used as cast iron modifiers |
Authors | Uskenbayeva A.M., Shamel’khanova N.A., Volochko A.T. |
Author´s information | K.I. Satpaev’s Kazakh National Research Technical University, Institute of industrial engineering, faculty of Machine-tool construction, materials science and technology of machine-building manufacture, Almaty Uskenbayeva A.M., doctoral student Shamel’khanova N.A., Cand Tech.Sci, Doctor of Education, professor Physicotechnical institute of the National academy of sciences of Byelorussia, lab. of Amorphous and microcrystalline materials Minsk, Belarus Volochko A.T., Dr. Tech.Sci., head of lab, Professor |
Summary | The results of spectral studies of the structure of various nano structured forms of carbon (graphene, carbon nanotubes, fullerene black) are presented in the article. They are added into the composition of complex modifier in order to produce high-quality iron castings with favorable structure of graphite and metal matrix. The carbon nanomaterials used as nanoadditives to modifier of cast irons relate to modifiers of new generation. They applied because of carbon is the strongest graphitizing material, which is part of many promising complex modifiers. The quality of these modifiers is connected with their structure, dispersion and content of harmful impurities. Obtained by Raman spectroscopy (RS) data are necessary for qualitative assessment of structural defects of the tested nano-additives. Detailed information about the structure of the materials, including vibration characteristics of atoms gives information about the degree of order and uniformity of the structure. RS results showed that various carbon nano-additives are characterized by heterogeneous structure at microlevel and contain defects as distortions, which forms carbon spectrum. It can be concluded by ratio ID/IG that the carbon nanotubes have smallest structure defect. Information about defects of selected sp2-carbon materials is important at the development of mechanisms of nanomodification. They are associated with adoption by melt the modifier, containing nano-additives of carbon and increase of the number of nucleation of graphite in cast iron, due to formation of new carbon-carbon bonds. |
Key words | nanomodification, carbon nanostructures, Raman spectroscopy, cast iron, graphene, carbon nanotubes, fullerene black |
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Investigation of electrochemical process
Kenzhaliyev B.K., Berkinbayeva A.N., Dosymbayeva Z.D., Sharipov R.H., Suleimenov E.N.The change in the parameters of the aqueous solutions during the electrochemical leaching of the secondary raw materials by using sulfur-graphite electrode
Title | The change in the parameters of the aqueous solutions during the electrochemical leaching of the secondary raw materials by using sulfur-graphite electrode |
Authors | Kenzhaliyev B.K., Berkinbayeva A.N., Dosymbayeva Z.D., Sharipov R.H., Suleimenov E.N. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, Almaty Kenzhaliyev B.K., Dr. Tech.Sci., рrofessor, president of “CESMOB” JSC Kazakh-British Technical University, Testing lab. of Perspective materials and technologies, Almaty Berkinbayeva A.N., Cand Tech.Sci, senior scientific worker, freedom.k@mail.ru Dosymbayeva Z.D., scientific worker Sharipov R.H., doctoral student, junior scientific worker Suleimenov E.N. ,Dr. Tech.Sci., head of lab., professor of cath. |
Summary | The research was conducted to develop a process of extracting non-ferrous metals from secondary raw material using the method of combined electrochemical reactions. The changes in the parameters (pH, conductivity, oxygen concentration) of an inorganic aqueous solution during leaching brass by using sulfur-graphite electrode (SGE) were investigated. Physicochemical characteristics of inorganic aqueous solutions obtained at the electrochemical leaching of metals from the alloy were determined. It was shown, how these parameters can be change by using SGE as a cathode and a brass (alloy of copper and zinc) as an anode. The electrochemical leaching of test alloy was performed in a temperature-controlled cell. SGE composition contains 65 % sulfur and 35 % graphite. Silver chloride electrode was used as a comparison – electrode, as an auxiliary – brass. During the experiment, the volume of the alkaline solution in the reaction vessel was 0.15 dm3 of sodium hydroxide, current density – 100 – 150 A/m2, rate of stirring – 480 rev/min., the leaching time – 5-6 hours. Initial alkali concentration in the leaching solution was 0.1, 0.2, 0.5, 1.0 M. The results of an X-ray analysis showed that during the leaching process, there is a division of initial components of the alloy into separately components containing copper and zinc. It was shown that a change in potential of the electrodes during the leaching can be used to regulate an extraction of various metals into an aqueous solution. Changes in the main characteristics of solution are irregular and independent from the metals and sulfur amount passing to solution and cannot be explained in terms of spontaneous electrolytic dissociation of components of solution microstructure. |
Key words | electrochemical leaching, sulfur-graphite electrode, oxygen concentration, electrical conductivity of solution. |
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Kilibayeva C.K., Yakhiyayeva Zh.Ye., Agapova L.Ya., Abisheva Z.S., Altenova A.N.Kinetics of cathodic reduction of ions of nickel, rhenium, tungsten and molybdenum from sulfuric acid electrolytes
Title | Kinetics of cathodic reduction of ions of nickel, rhenium, tungsten and molybdenum from sulfuric acid electrolytes |
Authors | Kilibayeva C.K., Yakhiyayeva Zh.Ye., Agapova L.Ya., Abisheva Z.S., Altenova A.N. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, lab of rare scattered elements, Almaty Kilibayeva C.K., Cand Tech.Sci, scientific worker Yakhiyayeva Zh.Ye., engineer Agapova L.Ya., Dr. Tech.Sci., head of lab, assistant professor, rm.303.imo@mail.ru Abisheva Z.S., Dr. Tech.Sci, Corresponding member of RK NAS, Director of Mines-Metallurgical Institute named after O.Bajkonurov of KazNRTU named after K.I.Satpaev Altenova A.N. leading engineer |
Summary | The results of research of kinetics of Ni, Re, W and Mo ions cathodic reduction from sulfuric acid fluoride and ammonium sulphate electrolytes in conditions of membrane electrolysis are presented in the article. The kinetics of cathodic reduction processes was studied for ions of metals individually and at their joint presence by volumetry method based on measure of amount of hydrogen evolved at the cathode depending on the process time. The values of the partial current densities and effective activation energy (Eph) of the processes of cathodic reduction of metals ions, and their mixtures in the temperature range 20-50 °C were calculated. It was found that in the sulfuric fluoride electrolytes the process of cathodic reduction of metals ions and their mixtures proceeds in the diffusion (Eeff 10,0-19,9 kJ/mol) and in the diffusion-kinetic (Eeff 37,4-47,4 kJ/mol) fields. In the temperature range of 30-50 °C the process of cathodic reduction of ions of Re, W, Mo and their mixtures is complicated because of formation of fluoride and sulfate inactive metals complexes or sedimentation of oxides on the cathode. In the temperature range of 20-40 °C in the ammonium sulfate-sulfuric acid electrolyte the process of cathode recovery of ions of Ni, Re, W, Mo and their mixtures flows in the kinetic region (Eeff 41,6-110,6 kJ/mol). In the temperature range of 40-50 °C the value of effective activation energy (58.2 kJ/mol) of cathodic reduction of W ions indicates on the kinetic nature of the process, and for ions of Ni, Re and mixtures of all metals ions the cathode recovery process is limited by diffusion difficulties (Eeff 8,3-33,2 kJ/mol). The current efficiency (СE) of metals at their cathodic reduction was determined depending on the composition of the electrolyte and cathode current density. The cathodic CE of metals from sulfuric acid fluoride electrolytes is higher than from ammonium sulphate solutions. |
Key words | kinetics, nickel, rhenium, tungsten, molybdenum, solutions, cathodic reduction, partial current density, current efficiency, activation energy |
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High-resistant refractories production
Biryukova A.A., Tikhonova T.A., Akchulakova S.T., Vakalova T.V., Govorova L.P.Influence of fluorinated additives on synthesis and properties of mullite ceramics based on silica-alumina raw materials of Kazakhstan
Title | Influence of fluorinated additives on synthesis and properties of mullite ceramics based on silica-alumina raw materials of Kazakhstan |
Authors | Biryukova A.A., Tikhonova T.A., Akchulakova S.T., Vakalova T.V., Govorova L.P. |
Author´s information | “Center of Earth sciences, metallurgy and ore benefication” JSC, Lab. of Metallurgical science, Almaty Biryukova A.A., Cand Tech.Sci, leading scientific worker, biryuk.silikat@mail.ru Tikhonova T.A., scientific worker Akchulakova S.T. , Cand Tech.Sci, leading scientific worker Tomsk Polytechnic University, Faculty of silicates technology and nano-materials, Tomsk, Russia Vakalova T.V., Dr. Tech. Sci., professor Govorova L.P. graduate student |
Summary | The chemical and mineralogical composition of refractory clays of Arkalyk and bauxites of Krasnooktyabrsk deposits is studied. It is established that the main rock-forming mineral of Arkalyk clay is kaolinite which at heat treatment of raw materials in the range of 1200-1500 OC will be transformed into mullite and cristobalite. The main mineral of the Krasnooktyabrsk bauxites is gibbsite. In the impurities there are high content of iron oxides in the form of hematite and low – of kaolinite. Corundum (Al2O3), mullite (3Al2O3 2SiO2), solid solution of iron in mullite and hercynite (Fe2Al2O3) are formed at heat treatment of bauxite in the range of 1150-1400 OC. Influence of fluorinated additives NH4FHF, MgF2, CaF2 on activation of processes of synthesis, agglomeration and hardening of structure of mullite ceramics on the basis of silica-alumina raw materials of Kazakhstan is studied. It is revealed that in compositions without additives the intensive mullite forming proceeds at 1350-1450 ОC, and in the presence of fluorinated additives – at temperature 1250-1400 OC. It is established that additives of NH4FHF, MgF2, CaF2 promote increase of the content of mullite at synthesis of silica-alumina ceramics on the basis of refractory clay and bauxite from 58-67 % up to 78-85 %. It is shown that fluorinated additives intensify processes of agglomeration and hardening of silica-alumina composition on the basis of Arkalyk clay and bauxite. Additives of fluorinated compounds allowed to reduce water absorption of silica-alumina ceramics from 5 to 0,5-2 %, and to increase durability on compression from 58 MPa up to 65-86 MPa. |
Key words | clay, bauxite, kaolinite, gibbsite synthesis, phase, mineralizing additive, sintering, water absorption, structure, strength |
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Industrial waste utilization
Kogan. V.S., Raikhman G.O.Hydrometallurgical recovery of copper, tin and silver from product of physical-mechanical processing of electronic scrap
Title | Hydrometallurgical recovery of copper, tin and silver from product of physical-mechanical processing of electronic scrap |
Authors | Kogan. V.S., Raikhman G.O. |
Author´s information | All Trade Recycling Ltd. company, research division, Petakh Tikva, Israel Коgan. V.S., Cand. Chem. Sci, head of division, Vladimir@atrecycling.com Raikhman G.O. general director of comp. |
Summary | The thermodynamics and kinetics of tin, copper and silver leaching from the light fraction of electronic scrap was investigated. The kinetic process is limited by diffusion of hydronium ions (H3O+) inside the tin solder particles and gaseous product of the acid dissolution of tin (H2) from the reaction slurry through the pores of the solid material. Generation of strong oxidizer as Cl2 in the slurry increases the rate of anodic processes on copper and silver. Formation of anionic complexes of Ag (I), which stability increases with increasing coordination number in the range AgCl2– |
Key words | combined physical-mechanical technology, electronic scrap, hydrometallurgy, thermodynamics, kinetics, leaching, copper, tin, silver, liquid-liquid extraction. |
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