Zirconium powder manufacturing process

FIELD: nonferrous metallurgy.

SUBSTANCE: invention relates to manufacturing zirconium powder for making pyrotechnic articles, in particular explosive and inflammable mixtures. By-layers prepared powered mixture of potassium fluorocirconate and alkali metal chloride, preferably sodium chloride, at ratio 1:(0.15-0.6) and sodium metal in amount exceeding its stoichiometrically required amount by 10-20%. Preparation involves grinding of potassium fluorocirconate and alkali metal chloride to fineness below 50 μm as well as preliminary recrystallization of potassium fluorocirconate. Charge is heated to temperature 450-600°C, at which reduction reaction starts and during this reaction reaction mixture heats to 700-800°C and reduction of potassium fluorocirconate takes place. Reaction products are cooled to 400-650°C and freed of sodium through vacuum distillation at residual pressure 1.3-13.3 Pa for 0.5-2.0 h, after which they are discharged from reaction vessel and ground. Zirconium powder is washed with water to remove fluoride and chloride salts and then dried. Zirconium powder contains 95-98% of fine fractions, including fraction below 10 μm in amount 45-55%.

EFFECT: enhanced fineness of prepared zirconium powder end assured fire safety of the process.

8 cl, 3 ex

 

The invention relates to ferrous metallurgy and can be used to obtain powders of zirconium for the manufacture of fireworks, in particular various explosive and flammable mixtures.

The main method of obtaining such powders is recovering ftorotsirkonatov potassium sodium reaction:

K2ZrF6+4Na=Zr+2KF+4NaF.

The recovery process is carried out with excess sodium in the charge, usually more than 20%. Excess sodium leads to ignition of the powder of zirconium in the process of extraction and crushing of the reaction mass and makes explosive washing powder of zirconium from other salts. Thus obtained powders arbitrary particle size distribution. At the same time, some applications require a powder in which the number of particle size less than 10 μm is more than 40%.

A method of obtaining powder of zirconium (see Zelikman A.I., Meyerson GA metallurgy of rare metals. - M.: metallurgy, 1973. - s) by restoring ftorotsirkonatov potassium sodium in a steel pressure reactor type "bomb" in a vacuum or argon at a temperature of 800-900°C. the Number of used metallic sodium at 20-30% above the stoichiometric required. After cooling, the fused mass is extracted, crushed, treated with a solution of ammonium chloride H 4Cl to remove excess sodium, crushed and washed with water to remove salts. Then the powder is treated with diluted hydrochloric acid to remove iron, washed with water and dried at 60°C.

The disadvantages of this method are the possibility of ignition of sodium and powder of zirconium when removing and crushing the reaction mass and explosion hazard when removing excess sodium solution of ammonium chloride. You get a powder arbitrary particle size distribution. Due to the high temperature process, the powders have insufficient content of particles less than 10 microns.

Also known is a method of obtaining powder of zirconium (see Wachs INC., Pepelyaev E.A., Vedyashkina L.A. Getting Zirconia restoration ftorotsirkonatov potassium metal sodium // proceedings of Giredmet (, 1931-1956). T.1. Technology. - M.: Metallurgizdat, 1959. - S-519), including accommodation in a steel crucible of ftorotsirkonatov potassium and metallic sodium in the form of alternating layers, on top of which poured a layer of potassium chloride to create sealing, and heating the mixture up to 800-850°With recovery ftorotsirkonatov. Upon completion of the reduction reaction of the crucible is cooled, the reaction mass is extracted and crushed. To remove excess sodium mass is treated with a solution of ammonium chloride. After that, the products p the action is crushed to a particle size less than 60 mesh, the Zirconia powder is washed with water to remove fluoride and chloride salts to the negative reactions of ions of chlorine and fluorine in the wash water. To remove iron and other impurities, the Zirconia powder is treated with a weak hydrochloric acid at 70-80°C for 20 minutes and Then produce washing powder water from chloride salts and dried.

The disadvantages of this method are the possibility of ignition of sodium and powder of zirconium when removing and crushing the reaction mass and explosion hazard when removing excess sodium solution of ammonium chloride. The obtained powders due to the high process temperature have insufficient content of particles less than 10 microns.

The present invention is directed to the achievement of the technical result consists in the provision of fire-fighting fashion with increasing content of fine fraction in the resulting powder of Zirconia.

The technical result is achieved in that in the method of producing Zirconia powder comprising placing in a reaction vessel charge of ftorotsirkonatov potassium, metallic sodium and chloride of an alkali metal, heating the mixture, recovering ftorotsirkonatov, cooling the reaction products, removing them from the reaction vessel, the removal of excess sodium, grinding of the reaction products, washing powder of zirconium from f origny and chloride salts and drying of the powder, according to the invention, the reaction products are cooled to amounts to 400-650°and the removal of excess sodium carried out by vacuum distillation at a residual pressure of 1.3 to 13.3 PA, and the removal of sodium lead before removing the reaction products from the reaction vessel.

The technical result is also achieved by the fact that florocarbon potassium and chloride of an alkali metal pre-ground to a particle size less than 50 microns.

The technical result is also achieved by the fact that florocarbon potassium before grinding is subjected to recrystallization.

The technical result is achieved by the fact that before placing in the reaction vessel florocarbon potassium mixed with the alkali metal chloride in a ratio of 1:0,15-0,6.

On the technical achievement of the aims that as alkali metal chloride using sodium chloride.

On the achievement of the technical result is also aimed that the charge is heated to 450-600°C.

On the achievement of the technical result is also aimed that the recovery ftorotsirkonatov potassium is carried out at a temperature of 700-800°C.

The achievement of the technical result is driven by the fact that the vacuum distillation are within 0.5 to 2.0 hours

Cooling the reaction products to amounts to 400-650°before removing excess sodium is because when the temperature is ISA 650° With the rate of removal of sodium excessively large, which complicates the condensation of sodium vapor. At temperatures below 400°With the rate of removal of excess sodium is low, which significantly lengthens the process and reduces the completeness of the removal of sodium.

Remove excess sodium vacuum distillation before removing the reaction products from the reaction vessel allows you to safely unload and crushing reaction products. There is no ignition of the powder and the allocation of aerosols oxides of the alkali metal in the environment, and eliminates the explosion hazard when washing powder from zirconium fluoride and chloride salts. In addition, increases the output of the Zirconia powder and the content of the fine fraction.

The implementation of vacuum distillation at a residual pressure of 1.3 to 13.3 PA provides the necessary completeness of the removal of excess sodium. At a residual pressure of more than 13.3 PA, the rate of distillation from sodium vapor is greatly reduced, which is undesirable. Providing a residual pressure of less than 1.3 PA impractical because unnecessarily complicates the way in the absence of any significant effect.

The combination of the above features is necessary and sufficient to achieve the technical result of the invention to provide fire-fighting method when increasing the attachment content of the fine fraction in the resulting powder of zirconium. This increases the safety of the method and improve working conditions.

The grinding ftorotsirkonatov of potassium and chloride of an alkali metal to a size less than 50 microns increases the fraction content of Zirconia powder with a particle size less than 10 microns.

Recrystallization of ftorotsirkonatov potassium helps to lower the strength of its crystalline particles, which enhances the grinding ftorotsirkonatov potassium to a particle size less than 50 microns.

Premixing of ftorotsirkonatov potassium chloride of an alkali metal has a positive effect on the increase of the content of fractions of powder with particle size less than 10 μm, as the chloride of the alkali metal plays the role of thermal ballast, reducing the maximum temperature of the recovery process and reduces the number of contact points between particles ftorotsirkonatov. When the ratio of ftorotsirkonatov of potassium and chloride of an alkali metal is less than 1:0,15 enlarging of the powder particles by increasing the process temperature and the number of contact points between particles ftorotsirkonatov. When the ratio of ftorotsirkonatov of potassium and chloride of an alkali metal more than 1:0.6 to reduced output of powder due to incomplete reaction of the restoration.

The use of sodium chloride as the chloride of the alkali metal due to the higher the Oh melting point of sodium chloride in comparison with other chlorides of alkali metals, which improves the dispersibility of the powder. In General, as the chloride of the alkali metal can be used potassium chloride with some deterioration of the dispersibility of the obtained Zirconia powder.

Heating the mixture to a temperature of 450-600°allows you to initiate the reaction and recovery to hold it in optimum temperature range. Upon heating the mixture to a temperature of less than 450°to initiate the reaction of the recovery is difficult. The final temperature of the reaction mass when it reaches 700°and the recovery will be incomplete. Heating the mixture to temperatures above 600°will lead to the fact that the final temperature of the reaction mass will exceed 800°and is formed With a powder of poor quality.

Carrying out the recovery process at a temperature of 700-800°allows you to optimize the particle size of the powder and to provide a high degree of recovery of zirconium. At temperatures below 700°With part of ftorotsirkonatov is not restored, which reduces the extraction of zirconium and reduces the quality of the powder. At temperatures above 800°is formed With powder unsatisfactory particle size distribution with a low content of particles less than 10 microns.

Carrying out vacuum distillation for 0.5-2.0 hours provides the necessary completeness of the removal of tochnogo sodium. At the time of distillation is less than 0.5 h the removal of excess sodium is not complete and the increase in time distillation over 2 h technologically and economically unjustified.

The above private features of the invention allow a method to optimally from the point of view of ensuring explosion and fire safety of the method and increase in the content of the fine fraction in the resulting powder of Zirconia.

In General, the method of producing Zirconia powder according to the invention is as follows.

In a cylindrical reaction vessel load layers prepared powdery mixture of ftorotsirkonatov of potassium and chloride of an alkali metal, preferably sodium chloride, taken in the ratio 1:0,15-0,6, and metallic sodium, taken in excess of the stoichiometric required by 10-20%. The preparation of the mixture may include grinding ftorotsirkonatov of potassium and chloride of an alkali metal to a size less than 50 microns, and optionally pre-recrystallization of ftorotsirkonatov potassium. The reaction vessel installed in the retort with water-cooled flange and close the lid with pipe. The retort is placed in a furnace and heated the mixture to a temperature of 450-600°at which the reaction begins recovery. In the course of the reaction is heated the reaction mass to t is mperature 700-800° With and restore ftorotsirkonatov potassium. Then the retort with the reaction products are cooled to amounts to 400-650°s With the nozzle on the lid of the retort is connected to the vacuum system and produce a distillation of sodium at a residual pressure of 1.3 to 13.3 PA for 0.5 to 2.0 hours After removal of the sodium, the retort is cooled to room temperature, taken out of the reaction vessel, extract the reaction products, crushed to a particle size less than 10 mm and loaded into a container of water. Then the pulp overload in the mill, where the reaction products optionally milled to a particle size less than 0.5 mm, the Liquid phase is decanted and the solid is loaded into the vessel with water for final washing of salts. If necessary, the obtained Zirconia powder can be processed 10-15% hydrochloric acid to remove metallic impurities, mainly iron with subsequent washing with distilled water until neutral. The Zirconia powder is filtered off, washed on the filter with distilled water and dried at a temperature of 60°in a vacuum Cabinet.

The nature and advantages of the invention can be illustrated by the following examples of carrying out the invention.

Example 1. 200 g of ftorotsirkonatov potassium particle size of 70 μm, dried at a temperature of 200°C, mixed with 30 g of sodium chloride, dried at a temperature of 600° (a ratio of 1:0.15 in), and see what camping loaded in layers with metallic sodium, taken in quantity to 71.5 g, which is 10% greater than the stoichiometric required in a steel cylindrical Cup with a diameter of 80 mm and a height of 130 mm Glass set in a retort made of stainless steel with water-cooled flange and close the lid with pipe. The retort is placed in a resistance furnace and heated to the temperature of the charge 600°C. Upon reaching this temperature, the reaction begins recovery. In the course of the reaction is heated the reaction mass to a temperature of 800°and restoring ftorotsirkonatov potassium. Then the retort with the reaction products are cooled to 650°s With the nozzle on the lid of the retort is connected to the vacuum system and produce a distillation of sodium at a residual pressure of 13.3 PA for 0.5 hours

After removal of the sodium, the retort is cooled to room temperature, take out the steel glass, extract the reaction products in the form of a sintered mass composed of a mixture of salts (NaF, KF, NaCl) with zirconium metal powder. The mass is crushed to a particle size less than 10 mm and loaded into a container of water. Then the pulp overload in the mill, where the reaction products optionally milled to a particle size less than 0.5 mm, the Liquid phase is decanted and the solid is loaded into the vessel with water for final washing of salts. The Zirconia powder is filtered off, washed on the filter with distilled water and is dried at a temperature of 60° With in a vacuum Cabinet. Get the powder of zirconium in the number 62,9 g with a particle size of less than 50 μm and content of particles less than 10 ám 45%. The output of the Zirconia powder was 98%.

When discharging reaction products and their crushing of spontaneous combustion of sodium and Zirconia powder was observed, and the interaction of the reaction products with water was not accompanied by explosive phenomena caused by the release of hydrogen.

Example 2. 200 g of ftorotsirkonatov potassium, pre-crushed to a particle size less than 50 μm and dried at a temperature of 200°C, mixed with 120 g of sodium chloride, dried at a temperature of 600°and crushed to a particle size less than 50 μm (ratio of 1:0.6 to). The mixture is loaded in layers with metallic sodium, taken in an amount 74,8 g, which is 15% higher than the stoichiometric required in a steel cylindrical Cup with a diameter of 80 mm and a height of 130 mm Glass set in a retort made of stainless steel with water-cooled flange and close the lid with pipe. The retort is placed in a resistance furnace and heated to the temperature of the charge 450°C. Upon reaching this temperature, the reaction begins recovery. In the course of the reaction is heated the reaction mass to a temperature of 700°and restoring ftorotsirkonatov potassium. Then the retort with the reaction products are cooled to 400°S, Patra is OK on the lid of the retort is connected to the vacuum system and produce a distillation of sodium at a residual pressure of 1.3 PA for 2 hours

Further, the process is carried out analogously to Example 1. Get the Zirconia powder in the amount of 61 g with a particle size of less than 50 μm and content of particles less than 10 microns - 55%. The output of the Zirconia powder was 95%.

When discharging reaction products and their crushing of spontaneous combustion of sodium and Zirconia powder was observed, and the interaction of the reaction products with water was not accompanied by explosive phenomena caused by the release of hydrogen.

Example 3. 200 g of recrystallized ftorotsirkonatov potassium, crushed to a particle size less than 50 μm and dried at a temperature of 200°C, mixed with 60 g of sodium chloride, dried at a temperature of 600°and crushed to a particle size less than 50 μm (ratio of 1:0,3). The mixture is loaded in layers with metallic sodium, taken in the amount of 78 g, which is 20% more than the stoichiometric required in a steel cylindrical Cup with a diameter of 80 mm and a height of 130 mm Glass set in a retort made of stainless steel with water-cooled flange and close the lid with pipe. The retort is placed in a resistance furnace and heated to the temperature of the charge 550°C. Upon reaching this temperature, the reaction begins recovery. In the course of the reaction is heated the reaction mass to a temperature of 750°and restoring ftorotsirkonatov potassium. Then the retort with the products of the reactions is cooled to 560° With the nozzle on the lid of the retort is connected to the vacuum system and produce a distillation of sodium at a residual pressure of 9 PA within 1 hour

Further, the process is carried out analogously to Example 1. Get the powder of zirconium in the number of 62.3 g with a particle size of less than 50 μm and content of particles less than 10 microns - 50%. The output of the Zirconia powder was 97%.

When discharging reaction products and their crushing of spontaneous combustion of sodium and Zirconia powder was observed, and the interaction of the reaction products with water was not accompanied by explosive phenomena caused by the release of hydrogen.

From the analysis above examples show that the proposed method provides explosion safety upon receipt of the Zirconia powder. The method allows to obtain a Zirconia powder with a particle size of less than 50 μm and content of particles less than 10 microns - 45-55% at high (95-98%) output powder.

1. The method of producing Zirconia powder comprising placing in a reaction vessel charge of ftorotsirkonatov potassium, metallic sodium and chloride of an alkali metal, heating the mixture, recovering ftorotsirkonatov, cooling the reaction products, removing them from the reaction vessel, the removal of excess sodium, grinding of the reaction products, washing powder from zirconium fluoride and chloride salts and drying powder, characterized in that the product of the s reaction is cooled to amounts to 400-650° And the removal of excess sodium carried out by vacuum distillation at a residual pressure of 1.3 to 13.3 PA, and the removal of sodium lead before removing the reaction products from the reaction vessel.

2. The method according to claim 1, characterized in that florocarbon potassium and chloride of an alkali metal pre-ground to a particle size less than 50 microns.

3. The method according to claim 2, characterized in that florocarbon potassium before grinding is subjected to recrystallization.

4. The method of claim 1 or 2, characterized in that before placing in the reaction vessel florocarbon potassium is mixed with alkali metal chloride in a ratio of 1:0,15-0,6.

5. The method according to claim 4, characterized in that the alkali metal chloride using sodium chloride.

6. The method according to claim 1, characterized in that the mixture is heated to 450-600°C.

7. The method according to claim 1 or 6, characterized in that the restoring ftorotsirkonatov potassium is carried out at a temperature of 700-800°C.

8. The method according to claim 1, characterized in that the vacuum distillation are within 0.5 to 2.0 hours



 

Same patents:

FIELD: metallurgy of refractory metals, possibly hydro-metallurgical processing of baddeleyite for producing zirconium dioxide of nuclear purity degree.

SUBSTANCE: method comprises steps of adding potassium ion in the form of potassium fluoride after complete dissolving of baddeleyite in acid and returning filtrate containing hydrofluoric acid to step of baddeleyite dissolving. Zirconium hydroxide is obtained by processing recrystallized crystals with solution of potassium hydroxide and prepared pulp is filtered. 1/3 of filtrate volume is returned to step of producing potassium fluorozirconate and 2/3 of filtrate volume is directed to step of recovering potassium fluoride. The last is recovered from filtrate due to processing filtrate with calcium hydroxide for producing potassium hydroxide. Generated calcium fluoride is directed to step of recovery where it is subjected to processing with sulfuric acid for producing hydrofluoric acid to be returned to step of dissolving baddeleyite. Potassium sulfate is used for different purposes in national economy.

EFFECT: reduced cost price of produced zirconium dioxide of nuclear purity, lowered consumption of chemical compounds, improved ecology of the whole process, decreased volume of sewage water.

3 cl, 1 dwg, 1 ex

FIELD: inorganic chemistry, hydrometallurgy, chemical technology.

SUBSTANCE: invention relates to a method for separation of hafnium and zirconium. Method involves extraction step of the parent aqueous mixture containing zirconium oxychloride, hafnium oxychloride and thiocyanate salt with a thiocyanate-containing organic solvent for preparing zirconium-containing aqueous raffinate flow and hafnium-containing organic raffinate flow, separation of organic raffinate flow from aqueous raffinate flow. In the aqueous parent mixture the ratio value of total acidity to the total sum of zirconium and hafnium oxides (TA/MO2) in maintained in the range from about above 2.55 to about less 3.5. Method provides optimization process for separating zirconium from hafnium by extraction procedure.

EFFECT: improved separating method.

21 cl, 2 dwg, 1 ex

FIELD: iodide refining of hafnium.

SUBSTANCE: interaction of iodine with black metal is carried out at temperature of 250-350°C. Sedimentation of refined hafnium is carried out at temperature of 1200-1600°C on heater (filament) made from molybdenum or zirconium wire in form of one or several loops connected to electrode end-pieces. Heater is formed in iodide refining apparatus in such way that lower part of each wire loop is suspended above insulator surface at clearance equal to 1/3-1/2 of final thickness of bar. Proposed method may be used for production of iodide hafnium bars more than 17 mm in diameter at height of heater loop more than 0.8 m.

EFFECT: enhanced purity by admixtures.

4 cl, 1 tbl, 3 ex

FIELD: hydrometallurgy.

SUBSTANCE: invention relates to a method allowing separation of some metals, in particular zirconium and haffnium. Method comprises separating metal 1 from metal 2 in aqueous solution of these metals. Being in solution, metals form polymers and/or copolymers, which prevents their passage through nanofiltration membrane. Method involves following stages: treating aqueous medium with ligand such as amino acid or poly(amino acid) to form complex with metal 1 or metal 2 followed by passing treated aqueous medium through filtration membrane. Membrane permeates through ligand-metal complexes but retains non-liganded metals.

EFFECT: achieved effective separation of zirconium for haffnium or other metals, zirconium/haffnium separation in a mineral or a fraction, and reduced separation temperature and operative expenses.

21 cl, 2 dwg, 3 ex

FIELD: production of pure zirconium by iodide refining method.

SUBSTANCE: proposed apparatus has retort and cover making it hermetic, current leads, cooling system and mechanism for delivery of iodine to retort. Peripheral screen chambers located inside retort are used for pouring initial material. Trapezium-shaped multi-loop zirconium wire tightened in space between chambers is used for deposition of pure metal on it. Upper and lower horizontal sections of wire loop are secured to metal disks by means of hooks on which electric insulating rings are fitted; length of horizontal sections does not exceed double diameter of finished bar. Wire is stretched by lower metal disk whose mass ratio to initial mass of wire ranges from 2.0 to 3.0.

EFFECT: increased productivity of apparatus; reduced amount of substandard metal.

3 dwg, 1 tbl

FIELD: metallurgy of zirconium.

SUBSTANCE: magnesium-reduced method of production of sponge zirconium includes preparation of magnesium for process, reduction of zirconium from its tetrachloride in presence of magnesium concentrate and its chloride of previous processes, obtaining reaction mass, cleaning this mass by separation in vacuum at precipitation of magnesium condensate and its chloride in condenser. For reduction, use is made of condenser filled with magnesium condensate and its chloride after separation process at addition of refined magnesium in form of ingots before precipitation of magnesium condensate and its chloride. Addition of refined magnesium may be performed by pouring its melt on magnesium condensate and its chloride before reduction of zirconium. Device proposed for realization of this method includes apparatus placed in vacuum separation furnace and filled with reaction mass and condenser interconnected by means of heated vapor line fitted with valve. Condenser is made in form of retort closed with cover with reaction sleeve placed inside it. Reaction sleeve is closed with shield of bottom part of cover sunken in it.

EFFECT: reduced specific consumption of magnesium per ton of sponge zirconium; reduced labor consumption at servicing the device.

4 cl, 1 dwg, 2 ex

FIELD: production of refractory metals, namely zirconium by electrolysis of melt salts.

SUBSTANCE: process comprises steps of electrolysis of melt of fluoride-chloride electrolyte containing, mass %: zirconium, 3 - 5, chlorine, 8 - 13; sodium, 2 - 4; cyclically charging to melt potassium fluozirconate, potassium chloride and sodium chloride for sustaining predetermined content of electrolyte; further separation of zirconium powder by hydraulic metallurgy; performing electrolysis at adding to melt magnesium chloride additive in quantity providing mass content of magnesium in electrolyte 0.05 - 0.5%.

EFFECT: improved current yield of zirconium powder at electrolysis, extraction of zirconium from initial salt to powder, lowered specific consumption of DC power.

1 tbl, 1 ex

FIELD: nonferrous metallurgy.

SUBSTANCE: invention aims at recovering uncommon metals from silicate ores and concentrates in processing of zirconium concentrates. Method according to invention envisages treating cake obtained by caking zircon concentrate with calcium oxide in presence of nitric or sulfuric acid. Concentrated acid is added to water-slurried cake at constant speed during 30-60 min in two steps so that 18-25% of acid is added during first 30 min, whereupon zirconium is leached at 80-90оС.

EFFECT: increased filtration velocity and simplified process due to reduced number of operations.

2 cl, 2 dwg, 4 ex

The invention relates to the metallurgy of rare metals, in particular to the field of reception of molten salt charterboat potassium - source materials for electrolytic or metallothermic Zirconia

The invention relates to the extraction and selective extraction of metal components, such as uranium, thorium, scandium and zirconium, from the source material, which consists of these components

FIELD: treatment of powdered, especially metal containing initial material introduced together with treating gas such as reducing gas for creating fluidized bed in fluidized bed chamber, for example in fluidized-bed reactor.

SUBSTANCE: treating gas at least after partial conversion in fluidized bed is removed out of fluidized bed and then outside fluidized bed it is partially recovered, preferably oxidized due to performing chemical, namely exothermal reaction with gaseous and(or) liquid oxidizer. Heat energy of such reaction at least partially is fed to fluidized-bed chamber, especially to fluidized bed or it is taken out of it. Cyclone is arranged over fluidized bed in fluidized-bed chamber. Powdered initial material is heated or cooled in zone of cyclone, namely near inlet opening of cyclone due to using treating gas at least partially recovered over fluidized bed in fluidized-bed chamber, possibly heated or cooled, and(or) due to using system for recovering treating gas.

EFFECT: possibility for decreasing caking on distributing collector of fluidized-bed reactor, lowered slagging in zone of fluidized bed.

10 cl, 1 dwg

FIELD: powder metallurgy, possibly production of finely dispersed powder of molybdenum, its composites with tungsten, namely for producing hard alloy materials on base of molybdenum and tungsten.

SUBSTANCE: method provides production of molybdenum and its composites with tungsten at temperature no more than 900°C and also production of materials in the form of finely dispersed powders. Method comprises steps of reducing compounds of molybdenum and tungsten (MoO3 and WO3) by metallic magnesium in medium of melt chlorides such NaCl, KCl or carbonates such as Na2CO3, K2CO3 or their binary mixtures such as NaCl - KCl, Na2CO3 - K2CO3, NaCl - Na2CO3, KCl - K2CO3 at temperature 770 -890°C. According to results of fineness analysis produced powder of molybdenum represents homogenous material having 80% of particles with fraction size 2.2 - 3 micrometers. Composition material depending upon Mo content includes particles with fraction size 5 - 15 micrometers.

EFFECT: enhanced efficiency of method.

1 tbl, 3 ex

FIELD: non-ferrous metallurgy, possibly production of highly purified powders of tantalum and niobium with large specific surface by metal thermal reduction.

SUBSTANCE: 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.

EFFECT: improved quality of valve metal powder, enhanced efficiency of process due to using heat separated at process of reducing valve metal for melting protection layer.

9 cl, 1 tbl, 4 ex

The invention relates to the metallurgy of tungsten, in particular the production of metallic tungsten from wolframalpha compounds, in particular SelidovUgol concentrate
The invention relates to powder metallurgy and can be used to obtain powder for capacitor production

The invention relates to ferrous metallurgy and can be used to obtain alloy powders of tantalum or niobium
The invention relates to metallurgy, in particular, to obtain granules and powders of rare and radioactive metals and their alloys

The invention relates to ferrous metallurgy and can be used to obtain high-purity powders of tantalum and niobium with a large specific surface for the production of capacitors

The invention relates to powder metallurgy and can be used to obtain high-purity powders of tantalum and niobium with a large specific surface for the production of capacitors
The invention relates to the field of powder metallurgy and concerns a method for obtaining powders of refractory compounds on the basis of a carbide or nitride of titanium compounds that can be used for the production of cutting tools, metal fittings, etc

FIELD: non-ferrous metallurgy, possibly production of highly purified powders of tantalum and niobium with large specific surface by metal thermal reduction.

SUBSTANCE: 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.

EFFECT: improved quality of valve metal powder, enhanced efficiency of process due to using heat separated at process of reducing valve metal for melting protection layer.

9 cl, 1 tbl, 4 ex

Up!