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Method of loparite concentrate processing Pyrometallurgical processing comprises three steps: reduction, smelting and oxidation. Reduction step comprises carbothermic reduction of concentrate at limited amount of carbon in the system to reduce solely refractory metals (RM) to their carbides to get the process mix of oxides of rare-earth elements (RE) and RM carbides. Smelting step separates RE from TM carbides. Said separation consists in dissolution of RM in liquid iron. This brings about iron containing RM and slag composed by target product, i.e. RE oxides. Third oxidation step consists in processing RM-bearing iron with oxygen to produce steel and iron on the base of RM oxides. |
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Treatment method of mixture of niobium and/or tantalum and titanium oxides Treatment method of a mixture of niobium and/or tantalum and titanium oxides for separation of niobium and/or tantalum from titanium involves dilution of the mixture at heating in the hydrofluoric acid solution so that a fluoride solution is obtained. A tetramethylammonium hydroxide solution or its salt is added at mixing to the obtained fluoride solution and evaporated to dryness. Formed complex fluorides of niobium and/or tantalum and tantalum with a tetramethylammonium cation are treated by low-molecular aliphatic ketone for extraction of complex niobium and/or tantalum fluorides in the form of tetramethylammonium hexafluoroniobate and/or hexafluorotantalate to the solution. Tetramethylammonium hexafluorotitanate is obtained in the deposit. |
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Method for opening perovskite concentrate Method involves carbothermal vacuum treatment. Prior to carbothermal treatment, a charge is prepared, which consists of perovskite concentrate and carbon-containing material in the ratio suitable for formation of calcium carbide, and titanium carbides and oxycarbides. Opening is performed in one unit in two stages. At the first stage, carbothermal treatment is performed at the temperature of 1100-1300°C and residual pressure of 10-100 Pa so that solid mixture of calcium carbides and titanium carbides and oxycarbides is obtained. The second stage is performed at the temperature of 1400-1500°C and pressure of 5-10 Pa for dissociation of calcium carbide and its stripping so that elementary calcium and carbon is obtained and with concentration in the residue of precious components of titanium, tantalum, niobium and rare-earth metals, which are contained in perovskite concentrate and are subject to chlorination. |
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Tantalum-base alloy refining method Tantalum-base alloy refining method involves vacuum electronic beam remelting in a horizontal crystalliser of the charge placed into it so that fumes of its metallic impurities are released on the surface that condenses them, and fumes of gas-containing impurities and production of a tantalum ingot by movement of an electronic beam from the beginning to the end of the crystalliser throughout the charge surface with its further switch-off. The charge contains metallic impurities of high-melting metals with the melting temperature close to that of tantalum. Vacuum electronic beam remelting is performed in two stages. The tantalum ingot produced at the first stage and containing impurities of high-melting metals is subject to electrochemical processing with release of tantalum-containing cathode residue that is subject to the second remelting stage so that an ingot of conditioned tantalum and fumes containing tantalum, which are returned to electrochemical processing, are obtained. From the first stage of the remelting process to the second one the specific power of an electronic beam is increased from 0.024-0.035 to 0.040-0.045 kW/mm2, and beam travel speed is decreased from 40-60 to 4-6 mm/min. |
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Method for obtaining pure niobium Method involves reduction of niobium pentoxide by means of aluminium and calcium so that rough niobium billets are obtained, their heat treatment and further multiple electron-beam melting of rough billets so that mainly non-oxidised fumes are formed after it is completed. Reduction is performed so that the above fumes are added. Prior to reduction the fumes formed after performance of the second and the next electron-beam melts are heated to the temperature of 600-800°C at residual pressure of not more than 0.1 mm Hg at least during one hour and hydrated at least during 12 hours. After hydration they are crushed till the size of ~1 mm, dehydrated and added to initial niobium pentoxide in the amount of 5-10% in relation to the weight of niobium pentoxide. Reduction process is performed at the following component ratio, wt %: Nb2O5:Al:Ca=1:0.22-0.24:0.27-0.29. |
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Method of producing niobium powder Invention relates to nonferrous metallurgy and may be used for metallothermic production of nanocrystalline niobium powders, mainly, for electrolytic capacitors. Niobium oxide compound, magnesium or calcium niobate, is reduced by vapors of magnesium or calcium. Reduction by magnesium vapors is carried at 600-950°C and by calcium vapors at 950-1050°C for 2-9 hours. Said reduction is performed in either vacuum at residual pressure of 1.3-13.3 Pa or atmosphere of argon or helium at 1-50 kPa. Reduction products are processed by solution of mineral acid to remove formed magnesium or calcium oxides. Obtained powder is flushed with deionised water to neutral state and dried. |
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Processing method of scraps of anodes of tantalum oxide-semiconductor capacitors Method involves cleaning of scraps by acid treatment with removal of manganese dioxide. Then, deoxidation of cleaned scraps, its hydration, grinding, dehydration at increased temperature is performed so that tantalum hydride powder is agglomerated and tantalum capacitor powder is obtained. At that, acid treatment is performed at room temperature using the solution containing 100-300 g/l of sulphuric acid and 110-300 g/l of hydrogen dioxide, or the solution containing 30-150 g/l of hydrochloric acid and 75-225 g/l of hydrogen dioxide. Scrap hydration is performed by treatment using the solution of hydrofluoric acid with concentration of 1-5%. The obtained capacitor tantalum powder provides specific charge of up to 7300 mcC/g, breakdown voltage of more than 200 V and leakage current of 0.0001-0.0003 mcA/mcC when being used in anodes of tantalum oxide-semiconductor capacitors. |
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Procedure for extraction of niobium and tantalum from titanium containing rare earth concentrate consists in treatment of fine crumbled concentrate with reagent containing octanol-1 saturated with fluoro-hydrogen acid with production of pulp by mixing; in transition of main part of niobium and tantalum and part of titanium in form of fluoro-metallate acids into extract and in concentrating residual part of niobium fluorides and tantalum in solid phase and another part of titanium in form of its fluoride compound. Further, pulp is settled and extract is separated from solid phase. Loparite concentrate is used as titanium containing rare earth metal concentrate. Titanium is concentrated in solid phase in form of non-hydrated fluoro-titanate of sodium. Octanol-1 saturated with fluoro-hydrogen acid to concentration 110-140 g/l is used as reagent, while treatment of concentrate is carried out at initial temperature 10-20°C. |
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Invention relates to metallurgy, namely, to producing barrier metal powders. Mix containing precursor of barrier metal and nonreacting liquid diluter is fused in first reactor. Said mix is placed in at least second reactor to add reducing agent therein. Reduction of barrier metal precursor to barrier metal is conducted at temperature and in interval that allow initiating reduction reaction. Produced powder features particle shape factor f defined from REM-images in the range of 0.65≤f≤1.00. |
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Extraction method of niobium (v) from fluorine-containing water solution Invention refers to extraction of niobium (V) from water fluorine-containing solution with the use of sorbents and can be used in non-ferrous and ferrous metallurgy, as well as for cleaning of industrial and domestic sewage systems. Method involves sorption by contact of solution and anionite. At that, sorption is performed at pH=1-4 with AM-2b anionite pre-treated with acid or water, and containing the following exchange groups: -CH2-N(CH3)2, -CH2-N(CH3)3. |
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Procedure for extraction of niobium from water solution containing fluorine Procedure for extraction of niobium from water solution containing fluorine consists in sorption by contacting solution and anionite. Anionite is subjected to acidic or water treatment before sorption. Sorption is carried out with anionite of grade ANP containing exchange groups at pH=2-4. |
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Procedure for production of primary refractory metal (versions) Procedure consists in heating chemically active gas containing gaseous hydrogen. Further, the procedure consists in bringing oxide of refractory metal to contact with said heated gas in form of particles of pentaoxide of tantalum for reduction of tantalum pentaoxide in form of particles. Also, weight ratio of gaseous atomic hydrogen and tantalum pentaoxide in form of particles is over 1.5:1 at temperature from 1900 °K to 2900 °K with formation of primary metal of tantalum. Another version of the procedure consists in heating chemically active gas containing gaseous hydrogen. Oxide of refractory metal is brought into contact with said heated gas in form of particles of niobium oxide chosen from a group containing of niobium dioxide, niobium pentaoxide and their combination for reduction of said niobium oxide in form of particles. Weight ratio of gaseous hydrogen and niobium oxide in from of particles is at least 9:1 at temperature from 2100°K to 2700°K with formation of primary metal of niobium. |
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Producing barrier metal powders with improved physical and electrical properties Invention relates to production of barrier metal powder to be used as anode material for electrolytic capacitors. Proposed method comprises feeding first barrier metal powder and reducing component into reactor with hot zone, making said powder and said reducing component interact in nonstatic conditions sufficient for simultaneous agglomeration of first barrier metal powder and reduction in oxygen content in said powder. Said interaction produces component consisting of second barrier metal powder containing barrier metal particles with reduced oxygen content. Note here that nonstatic conditions include agitating, dropping, rotating and combination thereof. Note also that reducing component is selected from the group comprising magnesium, calcium, aluminium, lithium, barium and strontium reducing components and combination thereof. |
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Removal of magnesium from powders recovered by magnesium Invention relates to production of high-quality powders of heat-resistant metals. In compliance with proposed method, powder containing magnesium tantalate and/or niobate is produced. Said powder is heated in inert atmosphere in the presence of magnesium, calcium and/or aluminium to temperature sufficient for removal of magnesium tantalate and/or magnesium niobate from the powder, and/or it is heated in vacuum to temperature sufficient for removal of magnesium tantalate and/or magnesium niobate from the powder. Note that heating is carried out in whatever sequence. |
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Method of producing valve metal powder Present invention relates to a method of reducing primary powder of valve metals and tantalum powder, suitable for use as anode material for electrolytic capacitors. The powder of valve metals is reduced by reducing metals such as aluminium, magnesium, calcium, barium and/or lanthanum and/or their hydrides, in an atmosphere of an inert carrier gas. Reduction is carried out without contact between the reduced powder of valve metals and the liquid reducing metal/metal hydride. The powdered metal and reducing metal/metal hydride are put into a reactor in different places so that the reducing metal/metal hydride can reach the powdered metal only in vapour form. Tantalum with specific surface area of 4-8 m2/g is pressed to density of 5 g/cm3 and sintered at 1210°C for 10 minutes. The obtained anode is formed at formation anode of up to 10 V has specific capacitance of 220000-350000 mcFV/g. Tantalum powder with specific surface area of 3.5-6 m2/g is pressed to density of 5 g/cm3 and sintered at 1210°C for 10 minutes. The obtained anode which is formed at formation voltage of up to 10 V has specific capacitance of 180000-250000 mcFV/g. |
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Reclamation of barrier metal powders Invention relates to reclamation of barrier metal powders, namely those of niobium, tantalum or alloys thereof. For this, metal is heated to temperature that exceeds melting point of reclaiming material. The latter is most frequently represented by lanthanum, yttrium or cerium. In using lanthanum, reclamation is performed at 940-1150°C. Besides reclamation is carried out in two stage. Note that barrier metal powder is reclaimed that has been produced in reclaiming barrier metal oxide by gaseous lanthanum, yttrium or cerium. |
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Metallothermic reduction of refractory metal oxides Invention relates to powder metallurgy. Component of oxide particles is mixed with reducing agent to form homogeneous mix. Obtained mix is fed into furnace for it to be ignited to initiate the exothermal reaction and produce high-temperature flashout. Note here that said mix is fed by disperser other than rotor/stator disperser to distribute it uniformly over the furnace cross section area, while mix furnace reaction zone location time TR varies from 0.1 s to 30 s. Oxide particles are selected from the group including refractory metal oxides, particles of refractory metal oxide alloys, powders of refractory metal sub oxides, powders of refractory metal sub oxides alloys and mixes thereof. Reducing agent is selected from the group including magnesium, aluminium, potassium and mixes thereof. In compliance with one of the versions, exothermal reaction is initiated at constant rate, while reaction zone temperature equal to flashout temperature is set to be constant. Besides exothermal reaction is initiated by heating the mix to ignition temperature or adding another reagent or catalyst. |
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Procedure for production of niobium and tantalum powders Invention refers to production of powders of valve metals, particularly to niobium and tantalum powders. Powders of oxides of corresponding valve metals are reduced by means of vaporous reducing metals and/or their hydrides, preferably at presence of inert gas-carrier. Reduction is carried out at partial pressure of reducing metal/metal hydride from 5 to 110 gPa and general pressure less 1000 gPa. Tantalum powder with specific surface 0.9-6 m2/g w reveals stability of agglomerates determined as ratio D50-value according to ASTM B 822 and value D50uv less, than 2, is more preferable; less, than 1.7, the most preferable, less, than 1.5 measured after ultrasonic treatment. |
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Method of processing perovskite concentrate with extraction of niobium and tantalum Method involves treatment of fine-grained concentrate by extracting agent - aliphatic alcohol saturated with hydrogen fluoride acid so that pulp is used. It is exposed and mixed with conversion of the main part of niobium and tantalum fluorides to organic phase, and titanium, calcium, lanthanides and the rest part of niobium and tantalum fluorides are concentrated in solid phase. Then pulp is clarified and extract is removed from solid phase. As extracting agent there used is pentanol or its mixture with octanol-1 or decanol at pentanol content in mixture of not less than 20% and at saturation of extracting agent with hydrogen fluoride acid till concentration is 119-184 g/l. Treatment of the concentrate with extracting agent is performed at the ratio S:L=1:7.5-10. |
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Method of fabrication of tantalum or niobium powder Method includes heating of charge, containing oxygenous or oxygenous and oxygen-free composition of tantalum or niobium and halogenide of alkali metal with formation of melt. Into melt it is introduced alkali metal at blending and it is implemented reduction of tantalum or niobium at temperature 550-850°C. Additionally amount of oxygen in melt is regulated by means of changing of ratio of components of harge according to relation where n(O) - amount of oxygen, mol, k - empirically determined coefficient, k=60-350 mol, m1 and M1 - mass and molar mass of oxycompound of tantalum or niobium correspondingly in kg and kg/mol, m2 and M2 - mass and molar mass of oxygen-free composition of tantalum or niobium correspondingly in kg and kg/mol, m3 and M3 - mass and molar mass of alkali metal halogenide correspondingly in kg and kg/mol. |
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Device for receiving of tantalum powder of condensing type Invention elates to metallurgical field, particularly to device for receiving of tantalum powder of condensing grade by magnesium-thermal recovery. Device contains heated rotating tubular reactor with rotating drive and magnesium evaporator. Reactor allows on inner surface of rib. Additionally evaporator and reactor are implemented in the form of sections of united horizontally located block, divided to each other by partition with central opening and are placed into waterproof vessel. Additionally vessel is outfitted by thermal shield, located from the side of input of rotating drive and is heated by furnace with zonal heating. |
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Production of valve metal powders Invention is related to production of valve metal powders. Valve metal compounds are reduced by alkaline metal in the presence of thinner salt. Reduction is done in the presence of substance that helps to decrease granules, which is added to reaction mixture periodically or continuously. Valve metal compound used is K2TaF7, Na2TaF7 or their mixture. Substance used to assist in decrease of granules, sulfur-containing, phosphor-containing, boron-containing and/or silicon-containing compounds are used. |
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Processing method of plumb-microlitic concentrate Concentrate is grinned up to size not more than 0.32 mm and treated by mixture 18-35% of nitrogenous and 40-45% hydrofluoric acids at mass correlation of acids 2.7-5.3:1, "Т:Ж"=1:3-5 and temeprature 90-120°C with formation of pulp. Nitro-acid lead (II), undecomposed minerals and radionuclides are transferred into sedimentation, and tantalum and niobium - into fluoride - nitro-acid solution. Pulp is cooled up to 10-20°C, lead-bearing deposit is separated and washed it by 35-50% nitric acid at "Т:Ж"=1:1.5-2.0. Scrub solution is affixed to fluoride - nitro-acid solution. From washed sediment it is leached nitro-acid lead (II) by water at correlation "Т:Ж"=1:5-10 and temperature 50-60°C with separation of undecomposed minerals and radionuclides and receiving of nitro-acid lead solution. From combined fluoride - nitro-acid solution it is implemented extraction of tantalum and niobium by neutral extragent. In the capacity of neutral extragent it is used triiso-amyl-phosphate or octanol-1. Extraction is implemented on 2-6 stages at O:B=1.5-2.0:1 with transferring of tantalum into organic phase and niobium - into aqueous. Extraction by triiso-amyl-phosphate is implemented at 2-4 stages, and extraction by octanol-1 - at 5-6 stages. |
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Method of manufacturing tantalum powder and facility for its implementation Method includes sodium-reduced reduction of potassium fluorine- tantalat while its fractional or continuous batching into alloyed sodium. Reduction is implemented at the temperature from 400 till 600°C and ratio sodium / potassium fluorine- tantalat from 5 till 10. Facility contains heated reaction vessel with cover, degassing system, letting in and exhaust of argon, control system and keeping of pressure of argon inside the facility. It is additionally outfitted by joint by means of pipeline for sodium movement with reaction vessel with the second heated vessel with beveled bottom and allowing cover with facility of sodium charge, connecting pipe of sodium feeding and degassing and connecting pipe of sodium discharge. At that reaction vessel is implemented with beveled bottom and has implemented as perforated storage tank of reduced product. Cover of reaction vessel is outfitted by charging connecting pipe of potassium fluorine- tantalat. |
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Invention concerns rare-metal industry. Particularly it concerns receiving of metallic tantalum by metallothermic reduction of its salts. For receiving of metallic tantalum charge, containing mixture of double complex chloride salt of tantalum - KTaCl6 and potassium chloride - KCl in ratio 1:(0.2÷0.5) by mass are fed by portions or uninterruptedly in the form of powder or melt on melt mirror of metallic sodium, taken in excess 60-80% of stoichiometrically necessary amount. Reduction is implemented at temperature 550-650°C, with speed of charge feeding 15-20 g/cm2·hour of area melt mirror of metallic sodium melt. Received reduced reactionary mass is subject to vacuum- thermal processing at temperature 500-540°C and residual pressure, not exceeding equilibrium pressure of sodium steams at temperature of vacuum- thermal processing of unreacted sodium. After vacuum- thermal processing it is implemented hydro metallurgical treatment of reactionary mass. |
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Invention refers to powder metallurgy, particularly to method and device for production of tantalum powder of high chemical purity; suggested powder can be utilised at production of condensers. The method consists in sodium-reduced reduction of potassium fluor-tantalate by means of batched or continuous dosing of potassium fluor-tantalate. Also reduction is performed at free fall of potassium fluor-tantalate crystals in the medium of inert gas and sodium vapors. The device contains a furnace heated reaction vessel with a cover and a sleeve for sodium charge, a system of degassing, intake and exhaust of argon, a system of control and maintaining of inert gas pressure inside the device. The device is equipped with condenser of excessive sodium connected to the reaction vessel. The reaction vessel is made in form of a vertical retort with ratio of diameter/height within ranges from 0.15 to 0.30, height over 800 mm and diameter over 200 mm with an expander in the upper part forming a circular chute. It contains a perforated collector of reduced product. The cover of the reaction vessel is made conic and is equipped with a potassium fluor-tantalate charge sleeve. The heating furnace of the reaction vessel is equipped with the sodium evaporation zone and zone of maintaining sodium in vaporous state. |
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Method of fabrication of tantalum powder Method includes reduction of fluorine tantalite of potassium with liquid sodium in medium of melted saline bath of halogenides of alkali metals by means of alternate portioned dozing of sodium, and further - of fluorine tantalite of potassium. Fluorine tantalite of potassium is introduced into mixtures with part of the charge of halogenides of alkali metals, used for making of a saline bath. Amount of halogenides of alkali metals in the mixture introduced into melt with fluorine tantalite of potassium constitutes from 60 to 125% (wt) from weight of fluorine tantalite of potassium. |
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Invention refers to extraction and concentration of thorium out of process waste of loparit concentrates treatment - spent melt of saline sprinkler filter (SSF) of loparit concentrate chlorination process. The method includes preparation of suspension by means of discharge of spent melt of saline sprinkler filter (SSF) into water, incorporation of high molecular flocculant, of holding, filtering, separation of sediment, obtaining of chloride solution, and of treatment with steel scrap and metal magnesium. Prior to obtaining chloride solution the source suspension is heated to 60-90°C and treated with solution of sodium hydroxide to pH 1.5-2.0 and to 0.1-0.3% solution of high molecular flocculant at amount of 3-5% from the source volume of suspension; then suspension is held for 2-4 hrs. Chloride solution is received by means of filtration of spent suspension obtaining sediment of rare metals; chloride solution is then treated with steel scrap and metal magnesium; at that the solution is successively treated first with the steel scrap at amount of 3-5 mass fractions of iron per 1 fraction of iron ions (III) in chloride solution at 80-100°C for 1-3 hrs till achieving the value of pH in a pulp equal to 3.0-3.5. Then the pulp is separated from the non-reacted portion of the steel scrap and is treated with metal magnesium to pH 3.5-4.5, and further with 0.1-0.3% solution of high molecular flocculant taken at amount of 5-20% from the volume of chloride solution. Thus produced pulp is held without mixing for 1-4 hrs and filtered producing thorium containing sediment; the said sediment is washed at filter first with solution containing 1-5 g/dcm3 of sodium sulphite, then with water. Washed out sediment is repulped in solution of sodium hydroxide with concentration of 50-150g/dcm3 at a ratio of "Ж:Т"=3-5 at 60-90°C for 2-3 hrs, after what the pulp is filtered with separation of alkaline filtrate. Thorium containing sediment at the filter is washed with water, pressed at the filter and dried; the alkaline filtrate and process water are merged and mixed, then heated to 80-90°C, and treated with solution of sodium hydroxide to pH 11-13 with production of hydroxide pulp. Hydroxide pulp is filtered and then radioactive sediment is produced at the filter; it is washed out with water and transferred to a special wastes depositary, while filtrate is mixed with 10-20 volumes of shop flush water, heated to 80-90°C and again treated with solution of sodium hydroxide to pH 11-13. Obtained pulp is held and filtered thus producing sediment of rare metals and deactivated chloride solution which is discharged to drainage. Sediment of rare metals is unloaded from the filter, merged with sediment of rare metals extracted from the source suspension, dried, washed out and then transferred for preparation of charge for its further chlorination together with the loparit concentrate. |
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Group of inventions pertains to the metallurgy of rare metals, in particular to the method of chloric decomposition of polymetallic niobium-tantalum containing raw material with obtaining of chlorides of niobium and/or tantalum and a device (chlorinator) for carrying out the chlorination process. The method involves chlorinating polymetallic niobium and/or tantalum containing materials in molten chlorides using chlorine, condensation and separation of the obtained pentachlorides of niobium and/or tantalum and chlorides of admixtures and tapping of the melt. Chlorination is done in the layer of melt with height of 500-1000 mm, containing iron chloride (up to 25% iron) and/or copper (up to 40% copper), as well as sodium chloride in quantity of not less than 1.2 kg for 1 kg of iron and not less than 2.2 kg for 1 kg of aluminium in the initial materials. The process is carried out at 550-850°C with consumption of chlorine of 1.7-2.2 kg for 1 kg of the initial materials. Tapping of the melt is done from the upper level through a tapping line. The chlorinator is water cooled, lined with graphite and equipped with a separation chamber, located in the upper part of the chlorinator. The ratio of the diameter of the chlorinator to the diameter of the separation chamber is equal to (2÷2.5):3, and the ratio of their heights is (1÷2):1. There is a removable graphite pipe for supplying chlorine, which runs through a water cooled connection pipe, tightly joined to the cover of the chlorinator, to the bottom of the chlorinator. Tapping of the melt is done from the upper level through a heated tapping line, lined with graphite. |
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Valve metal powder production method Method is realized at using as corrosion protection means layer of halide of alkali metal formed on inner surface of vessel before creating in reaction vessel atmosphere of inert gas. Charge contains valve metal compound and halide of alkali metal. It is loaded into reaction vessel and restricted by protection layer of halide of alkali metal having melting temperature higher than that of charge by 50 - 400°C. Before loading charge, valve metal compound and alkali metal halide may be mixed one with other. Mass of protection layer of alkali metal halide Ml and charge mass Mc are selected in such a way that that to satisfy relation Ml = k Mc where k - empiric coefficient equal to 0.05 - 0.5. Gas atmosphere of reaction vessel contains argon, helium or their mixture. Fluorotantalate and(or) oxyfluorotantalate or fluoroniobate and(or) oxyfluoroniobate of potassium is used as valve metal compound. Sodium, potassium or their mixture is used as alkali metal. Chloride and(or) fluoride is used as alkali metal halide. Valve metal compound and alkali metal halide may contain alloying additives of phosphorus, sulfur, nitrogen at content of each additive in range 0.005 - 0.1% and 0.005 - 0.2% of mass valve metal compound respectively. Invention lowers by 1.3 - 2 times contamination of powder with metallic impurities penetrating from vessel material. Value of specific surface of powder is increased by 1.2 - 1.8 times, its charge is increased by 10 - 30 %, leakage current are reduced by 1.2 - 1.5 times. |
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Method of a loparite concentrate processing The invention is pertaining to the field of hydrometallurgy, in particular, to processing of the loparite concentrate. The method includes a decomposing of the loparite concentrate at the temperatures of 103-105°C and the concentration of hydrofluoric acid of 38-42 mass % with production of the pulp containing fluorides of titanium, rare earth elements (REE), niobium, tantalum and sodium. The pulp is filtered at the temperature of 90-95°C with extraction into the fluorotitanium solution of fluorides of niobium and tantalum and no less than 58 % of sodium in terms ofNa2O and separation of the sediment containing fluorides of rare earth elements (REE) and a residual sodium. The produced solution is cooled down to 18-24°C with separation of the second sediment of sodium fluorotitanate. After that they extract niobium and a tantalum from the solution by octanol-1 extraction at a ratio of the organic and water phases as 1.1 : 1. The sediment of REE fluorides is washed from fluorotitanate by sodium water in a single phase at the temperature of 90-95°C and at the solid :liquid ratio = 1:2-2.5. The cleansing solution is separated and evaporated with extraction of the additional sediment of sodium fluorotitanate. After extraction of niobium and tantalum the fluorotitanium solution is evaporated and filtered with separation of the first sediment of sodium fluorotitanate from the concentrated solution of fluorotitanium acid, which is directed to extraction of titanium. The gained first, second and additional sediments of sodium fluorotitanate are combined and subjected to conversion with production of sodium fluorosilicate and the conversional fluorotitanium acid added to fluorotitanium solution before its evaporation. The technical result of the invention is a decrease in 2.0-2.5 times of the volume of the cleansing solutions at provision of a high degree of extraction of compounds of titanium and other target products. The produced sodium fluorotitanate contains the decreased amount of the impurity ingredients of calcium and strontium. |
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Method for extraction separation of tantalum and niobium from acid fluoride-sulfate solution Invention relates to a method for extraction separation of tantalum and niobium. Method involves extraction separation of tantalum from niobium with organic solvent. As an organic solvent method involves using a mixture of methyl isobutyl ketone taken in the amount 40-80 vol.% with aliphatic (C7-C9)-alcohol taken in the amount 20-60 vol.%. At the extraction process tantalum transfers into organic phase and niobium - into aqueous phase. Then organic and aqueous phases are separated. Invention provides enhancing the extraction degree of tantalum into organic phase and to enhance the separation degree of tantalum and niobium in extraction. |
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Charge for production of niobium-bearing material and a method of its preparation The invention is dealt with production of niobium-bearing materials used for production of special steels. The technical result is an increased degree of transition of niobium into an alloy, decreased share of impurities in the alloy, decreased production costs. For this purpose the charge for production of a niobium-bearing material contains the raw material containing niobium pentaoxide, a nickel-bearing material, aluminum, calcium oxide, calcium fluoride and an exothermic oxidative additive. At that in the capacity of the exothermic oxidative additive it contains potassium chlorate with moisture of 2-12% at the following ratio in shares in respect to the total weight of the charge: niobium pentaoxide - 0.470-0.520, nickel - 0.190-0.270, aluminum - 0.180-0.200, calcium oxide - 0.030-0.040, calcium fluoride - 0.003-0.004, potassium chlorate with moisture of 2-12% - 0.043-0.049. At preparation of the charge after mixing of components it is exposed to compaction in the crucible up to the value of the plastic strength of 0.4-10.0 MPa. |
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Method for producing high-purity niobium ingots with normalized level of electrophysical properties Method comprises steps of electron-beam refining of consumable niobium blank; using blank of niobium of given kind containing niobium uniformly distributed along its length and produced by iodide refining as consumable blank in order to produce niobium ingots with predetermined (in range 200 - 500) relation of specific resistances at temperature values 193K and 9.2K; determining mass relation of niobium of given kind and niobium produced by iodide refining according to relation of specific resistances at temperature values 193 K and 9.2 K with use of expression mn/mu = (500 - ρ293/ρ9.2)/(800 + 2 x ρ293/ρ9.2) where mn - mass of niobium of given kind, g; mu - mass of niobium produced by iodide refining, g; ρ293 - specific resistance of niobium at temperature 193K, ohm x m2/m ; ρ9.2 - specific resistance of niobium at temperature 9.2K, ohm x m2/m. |
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Method for production of pure niobium Method includes reducing fusion of niobium pentoxide with aluminum and calcium to provide crude ingots followed by heat treatment and multiple electron beam refining. As an additional raw material in step of reducing fusion sublimates (preferably in non-oxidized form) from second and subsequent electron beam refining are used. Such sublimates are obtained by subsequent cooling of furnace smelting chamber under residual pressure of 10-2-10-4 mmHg for 1.0-3.0 h, letting-to-helium under 1-3 mmHg for 1.0-3.0 h, and letting-to-air for 20-40 min. Sublimates are added in amount of 4.5 % based to feeding niobium pentoxide. Claimed method affords the ability to increase niobium pentoxide consumption by 73 kg in respect to 1000 kg of pure niobium in crude ingots. |
Another patent 2513929.