Method of producing ultramicrodispersed nickel oxide powder using ac
SUBSTANCE: method of producing ultramicrodispersed nickel oxide powder includes electrolysis in 17 M sodium hydroxide solution under alternating sinusoidal current at 20Hz with nickel electrodes. The process of electrolysis is carried out at temperature of 20-30°C and voltage across the electrodes of 4V.
EFFECT: method for producing ultramicrodispersed nickel oxide powder suitable for use in catalytic production of nanocarbon materials by pyrolysis of hydrocarbons while reducing heating costs and simplifying its cell structure.
The invention relates to methods for producing powders of metal oxides, and in particular to methods of obtaining ultramicrobacteria powder of Nickel oxide. The resulting powder can be used to prepare the catalysts used in the synthesis of carbon nanotubes.
There are different ways of obtaining ultramicrobacteria particles of Nickel and its oxides. They can be divided into three large groups: chemical, physical and physico-chemical methods.
1. Chemical methods
These include vapor deposition, recovery in solid and liquid phase pyrolysis, Sol-gel technology.
Method for the synthesis of nanosized particles of Nickel oxide is in the deposition of nitric acid solution in ethanol medium (ethanol, propanol), a diluted solution of sodium hydroxide at a temperature of 60...80°C, followed by washing precipitation with water, and drying at 50°C. the Obtained hydrated oxides of Nickel NiO·nH2O have a specific surface area of 280 mg/cm2[L.N. Trushnikova, V.V. Sokolov, V.V. Bukovec. Obtaining nanosized particles of oxides of cerium, copper, cobalt and Nickel // the Second all-Russian conference on nanomaterials, "Nano-2007". 13-16 March 2007. Novosibirsk. S]. One of the problems of receiving such materials from aqueous solutions is the agglomeration of ultram the nkiye particles. To prevent clumping use organic liquids, including alcohol. This expensive and inefficient method finds application in laboratories and for special purposes.
There is a method for the synthesis of nanosized powder of Nickel oxide deposition from solution and in which as initial reagents used nitrate of Nickel, and the precipitant is ammonium carbonate [A.G. Belous, AS Yanchevskii, ALEXANDER Kramarenko. Getting nanomateriales oxides of Nickel and cobalt from solutions // Journal of applied chemistry, 2006, №3. S.353-357]. Formed during thermal decomposition of basic carbonate particles of Nickel oxide have a rounded shape with particle sizes of 5-10 nm.
Nanoparticles of Nickel synthesize traditionally-chemical method in reverse micelles [SV Gornostaeva, A.A. Revin. Synthesis and properties of nano-size particles of Nickel and nanocomposites // physical chemistry of surfaces and protection of materials. 2008. No. 4. S.400-403]. To prepare the solution using hydrated nitrate Nickel and trichitillomania water. To obtain reverse micelles as a surface-active composition used a solution of bis(2-ethylhexyl) and sulfosuccinate sodium in isooctane. Adsorption of nanoparticles of Nickel is carried out on silochrome. The prepared solution is irradiated on the installation RKHM-γ-20 (source60/sup> Co). Absorption of radiation dose on ferrosulfate the dosimeter equal 0,26 G/C. Zlecenia dose - of 17.8 kGy. The resulting Nickel nanoparticles have a spherical shape and sizes of the order of 1 to 100 nm. Found that the oxygen of the metallic Nickel particles are oxidized to nanoparticles of Nickel oxide (II).
Method for obtaining nanosized particles of Nickel oxide chemical recovery from aqueous solutions of salts of Nickel [A.L. Novozhilov, GV Narseev, L.V. Serov. Obtaining nanoparticles of Nickel // VII international conference. Moscow - Stavropol: Sevkat, 2007. - 510]. As a stabilizer using 1% aqueous solution of polyvinyl alcohol as a reducing agent used sodium borohydride. The concentration of Nickel sulfate range from 0.1 to 0.001 mol/DM3, sodium borohydride is from 1.0 to 0.01 mol/DM3. The resulting suspension is very stable and remain in suspension for more than a week. The sizes of the particles in this solution, have an average radius of 280 nm, with a large asymmetry of the distribution curve in the direction of increasing particle size.
The Nickel powder is produced by recovery from solutions of salts of Nickel, elemental phosphorus, taken in its active form in an alkaline environment, and before recovery to the original solution injected silicone grease [A.S. No. 1479539, to the. SI 23/04, 16.03.87, publ. 15.05.89]. The resulting powders have a high ferromagnetic properties, and low bulk weight.
A known method of extraction of the Nickel powder from waste solutions chemical Nickel plating, including his recovery from solutions by hypophosphite sodium, characterized in that to reduce the content of Nickel ions in the solution to the maximum permissible concentrations in the waste electroplating plants recovery of Nickel is carried out in the presence of the Nickel powder at a pH of 6.5...7,0, temperatures 65...70°C, and the ratio of the content of Nickel ions and hypophosphite sodium 1:5 [A.S. No. 1673616, CL C22B 3//44,C22B23/00, 31.05.89, publ. 30.08.91].
Known methods for producing the Nickel powder by restoring its salts with hydrogen by the method [Application Germany No. 2244746, CL C22B 23/04, publ. 10.07.75] solution douglasthe Nickel is treated with gaseous ammonia or aqueous ammonia solution, the precipitate Ni(NH3)6Cl2separated by filtration, dried to a partial transformation in Ni(NH3)2Cl2and restore at 450...1000°C hydrogen; by the way [France Application No. 2227336, CL C22B23/04, B22A 9/00, publ. 27.12.75] the source of Nickel salt solution is treated with alkali metal oxalate, restore the sediment in the autoclave with hydrogen in the presence of a hydroxide of an alkali metal.>
Method for obtaining Nickel powder by hydrogen deposition in an autoclave at elevated temperature and pressure [A.S. No. 1126374, CL B22F 9/24, C22B23/04, 18.05.82. publ. 30.11.84]. With the aim of increasing the activity of powder and cheaper process, the deposition of lead from aqueous slurry of Nickel carbonate with the addition of sulfate ion in the amount equivalent to 0.05 mol of Nickel per 1 mol of Nickel carbonate, and after deposition of the slurry is injected inhibitor with restorative properties. As an inhibitor use formic acid in the amount of 0.5 to 2 g per 1 DM3slurry of Nickel powder.
2. Physical methods
These include techniques based on the processes of evaporation and condensation. The powders are formed as a result of the phase transition of vapor - solid or vapor - solid - liquid in the gas volume or on the surface to be cooled.
Developed a new process of manufacturing a Nickel nano-powder in an atmosphere of various gases (air, argon, nitrogen, helium, xenon. The process is the evaporation of solid natural or technogenic raw materials, followed by rapid cooling of high-temperature steam and condensation of matter in the form of nanoparticles [S. p. Bardachanov, A. I. Korchagin, NICHOLAS Kuksov, A. Lavrukhin, R.A. Salimov, S.N. Fadeev, V.V. Shards. Getting managesearch powders on a powerful mustache is oritel electrons at atmospheric conditions // Laurentian reading, mathematics, mechanics and physics. Novosibirsk, 27-31 may, 2005 http://www.ict.nsc.m/ws/show_abstract.dhtml?ru+120+66]. The latter can have different sizes from 10 to 500 of them. The process provides a temperature sufficient to vaporize any material at the heating temperature of more than 1000 K/s Additional advantage is fewer production stages.
Obtaining a powder of Nickel oxide is also an electric explosion of Nickel wire with different diameters and length [Y.A Kotov, A.V. Bagazeev, IV Beketov. Characterization of powders of Nickel oxide obtained by electrical explosion of wire // Journal of technical physics. 2005, volume 75, issue 10. P.39-41.]. Apply discharge circuit with an inductance of 0.5 μh, and the capacitance of the capacitor Bank 3,2 international film festival. Charging voltage change from 10 to 33 kV. The explosion is carried out at normal pressure in a mixture of nitrogen and oxygen and the change in concentrations of from 10 to 30%. The resulting particles have different shapes both monocrystalline and polycrystalline structure with a particle size of about 100 nm.
3. Physico-chemical methods
These include the processes of evaporation - condensation involving chemical reactions, electro-deposition, drying - freezing.
Ultramicrobacteria powder of Nickel oxide can be obtained by the method of freeze-drying [Roehrig F.K., Wright .R. Freeze drying: a unigue aproach to the synthesis of ultrafme powders. - J. Vac. Sci. and Techn., 1972. 9. No. 6. P.1368-1372]. Of raw materials, in particular metal salts, prepare a solution of the required composition, which quickly freezes by spraying into the chamber with a cryogenic environment (e.g., liquid nitrogen). Then the pressure of the gaseous medium above the frozen granules is reduced so that it was below the equilibrium point formed by the cooling system, and the material is heated in a vacuum to the sublimation of the solvent. The resulting product consists of a very thin porous granules of the same composition. Further processing depends on the purpose of the final powder. Calcination of the pellets in the air, you can get the oxides of Nickel, recovery powder suitable metal.
The Nickel powder is produced by electrolysis of ammonium sulfate solutions of Nickel (the source material is with NISO4·7H2O). The electrolyte contains 5...15 g/DM3Nickel (Ni % 75...80 g/DM3ammonium sulfate, 2...3 g/DM3sulfuric acid, 40...50 g/DM3ammonium chloride and 200 g/DM3sodium chloride. The electrolysis is conducted at the temperature of the electrolyte 35...55°C, current density of 1000...3000 a/m2and the voltage on the tub 10...15 Century, the current Output is up to 90...94%, and the power consumption of about 3000 kWh/t [Libenson GA Fundamentals of powder metallurgy. M: Metallurgy. 1975. s].
The described process is perceived by the Oia powders of oxides of Nickel by electrolysis on a symmetric alternating current (50 Hz), according to which the maximum rate of destruction of the Nickel - 20 mg/(cm2·h) was observed in 46% sodium hydroxide solution at current density of 2.5 a/cm, the electrolyte temperature 70°C [V.V. Korobkin. The destruction of Nickel and cadmium in the electrolysis of alternating current of industrial frequency // Bulletin of the Tomsk Polytechnic University. 2003. No. 1. P.23-24].
The closest in technical essence and the resulting effect to the claimed method is a method of obtaining Nickel oxide, described in [EJ Nikiforova and other "Development of an electrochemical method of producing ultramicrobacteria powder of Nickel oxide by electrolysis in an alternating sinusoidal current". Proceedings of the II all-Russian scientific-innovative youth conference with international participation "Modern solid state technology: theory, practice and innovation management". - Moscow: Publishing house of the GOU VPO TSTU, 2010. - S-237] (prototype). The method is carried out in a thermostatted cell 17 M solution of sodium hydroxide at a current frequency of 20 Hz and the voltage on the electrodes 4 Century. a Constant solution temperature of 70°C in a cell support with the help of a thermostat with an accuracy of 0.5°C.
Our proposed method of obtaining ultramicrobacteria powder of Nickel oxide on an alternating sinusoidal current with Nickel electrodes is 17 M solution of hydro is sid sodium, when the current frequency of 20 Hz, a temperature of 20-30°C and a voltage of 4 C. the Rate of destruction of the Nickel electrodes (education ultramicrobacteria powder of Nickel oxide) is not reduced in comparison with the prototype.
The method is as follows.
The electrolysis is performed on an alternating sinusoidal current at the Nickel electrode, the cell volume of 200 cm3at a current density of 2.5 a/cm2, frequency current of 20 Hz and a temperature of 20-30°C, when the voltage at the electrodes 4 C. the Electrode and thermometer fixed in the insulating cover, for example, PTFE or polypropylene. After a predetermined time process, the electrodes are removed from the cell, washed with distilled water and alcohol, and then weighed on an analytical balance. The resulting powder was separated by filtration, washed with distilled water, dried and weighed. The rate of destruction of Nickel and education ultramicrobacteria powder of Nickel oxide determined by the gravimetric method.
A distinctive feature of the proposed method is:
is that the electrolysis process is carried out at a temperature of 20-30°C and the voltage on the electrodes 4 Century
The proposed method of obtaining powder of Nickel oxide is illustrated by the following examples:
Electrolysis 17 M sodium hydroxide solution with an alternating current spending is in the electrochemical cell the Nickel electrodes. The temperature of the starting solution is 20°C, the voltage at the electrodes is 4 Century, the Rate of destruction of Nickel determined by the gravimetric method. The surface speed of the destruction of Nickel is 75 mg/(cm2·h).
Electrolysis 17 M sodium hydroxide solution, with an alternating current, is carried out in the electrochemical cell the Nickel electrodes. The temperature of the starting solution is 25°C, the voltage on the electrodes is 4 Century, the Rate of destruction of Nickel determined by the gravimetric method. The surface speed of the destruction of Nickel is 75 mg/(cm2·h).
Electrolysis 17 M sodium hydroxide solution, with an alternating current, is carried out in the electrochemical cell the Nickel electrodes. The temperature of the starting solution is 30°C, the voltage at the electrodes is 4 Century, the Rate of destruction of Nickel determined by the gravimetric method. The surface speed of the destruction of Nickel is 75 mg/(cm2·h).
The method of obtaining ultramicrobacteria powder of Nickel oxide in 17 M solution of sodium hydroxide by electrolysis of an alternating sinusoidal current with frequency of 20 Hz with Nickel electrodes, characterized in that the electrolysis process is carried out at a temperature of 20-30°C and the voltage on the electrodes 4 Century
SUBSTANCE: cathode comprises current lead and working surface composed of the surface of sharpened elements isolated by dielectric. Said dielectric is a bulky figure with sharpened element ends located on its surface. Note here that the area of said elements is minimum.
EFFECT: faster process.
1 dwg, 2 ex
SUBSTANCE: procedure consists in electrolysis with asymmetrical alternate current of 50 Hz frequency at heating in alkali medium. Electrolysis is carried out at density of current of anode and cathode half-periods 2.5 A/cm2 and 0.5…2 A/cm2 correspondingly, while size of parts of produced nickel oxide is 9…20 nm.
EFFECT: production of ultra-micro-dispersed powder of nickel oxide applicable for usage in catalytic production of nano carbon materials by pyrolysis of hydrocarbon raw stock.
2 cl, 4 ex
SUBSTANCE: there are used soluble and insoluble anodes connected to separate sources of current for control over soluble anode dissolution during process of electrolysis and concentration of ions of metal in solution by means of correcting ratio of anode strengths of current of soluble and insoluble anodes at constant value of cathode density of current. Also, constant value of cathode density of current is achieved by constant area of cathode and sum of current strength on the soluble and insoluble anodes.
EFFECT: avoiding labour-intense operation of correction of electrolyte due to equalising cathode and anode current outputs at production of powders of metal.
8 dwg, 3 ex
SUBSTANCE: metal particles from electrolyte are deposited on substrate till the stage of formation of icosahedral micro- and nano-particles is ended. Then, particles are subject to annealing in neutral medium at temperature of 450-500°C with exposure during 25-60 minutes. Heating to annealing temperature is performed with speed of 5-15°C/min. After annealing the conditions for particle destruction are created. Obtained micro- and nanoparticles are separated from substrate prior to annealing or after annealing.
EFFECT: enlarging specific surface area of obtained powders and improving efficiency of their use.
3 cl, 4 dwg
SUBSTANCE: invention relates to production of copper nanoparticles to be used as biocide component in medicine and veterinary science. Proposed method comprises dissolving stabilising components in solvent, introducing anode nanoparticles, in the form of copper plate and node, into stabiliser solution, and electrochemical dissolution of anode in causing stabilised direct current to flow through the solution. Note here that distilled water is used as a solvent, while organic and inorganic stabilising components are used as stabilisers. Dissolution of stabilising components is carried out in two stages. Note here that, first, in heating and mixing, organic stabilising components are dissolved, and, then after cooling at mixing, inorganic components are dissolved. Note also that stainless steel plate is used as cathode.
EFFECT: copper nanoparticles are produced in aqueous medium that features high stability.
1 tbl, 6 ex
SUBSTANCE: invention relates to production of copper nanoparticles to be used as biocide component in medicine and veterinary science, etc. Proposed method comprises dissolving stabilising components in solvent, introducing anode nanoparticles, in the form of copper plate and node, into stabiliser solution, and electrochemical dissolution of anode in causing stabilised direct current to flow through the solution. Note here that distilled water is used as a solvent, while organic and inorganic stabilising components are used as stabilisers. Dissolution of stabilising components is carried out in two stages. Note here that, first, in heating and mixing, organic stabilising components are dissolved, and, then after cooling at mixing, inorganic components are dissolved. Note also that stainless steel plate is used as cathode.
EFFECT: production of nanoparticles with strongly pronounced bactericidal Catalytic, antirust and magnetic properties.
1 tbl, 6 ex
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, in particular, to production of electrolytic powders. To produce silver powders, silver is settled down from electrolyte containing hydrogen nitrate silver nitrate at electrolyser plant comprising soluble anode made from silver and cathode. Flocculants "АК" or "Магнафлок" are added as polyacrylamide-based surfactants into electrolyte in amount of 30-200 mg per 1 kg of produced silver powder. Deposition is performed at revering current and periodic change of anode and cathode polarity.
EFFECT: high yield of powders.
1 tbl, 1 ex
SUBSTANCE: invention relates to powder metallurgy, particularly to silver powders for electrodes of chemical current source and metalceramic contacs and method of its receiving. It is precipitated silver hydroxyde from the solution of silver nitrate by solution of potassium hydroxide. Received silver hydroxyde is flushed and thermally disintegrated for silver oxide and water. Received silver oxide is mechanically treated and it is implemented thermal reconditioning up to metallic silver. Received powder is flushed from potassium hydroxyde at temperature 60÷80°C during 30÷60 minutes, crushed and compacted in ball crusher during 15÷20 minutes and separated for particle fractions by sizes. Received silver powder consists of cellular particles of value less than 56 mcm, with pores size in particles 0.3-3.0 mcm, allows specific surface area 0.07-0.12 m2/g and packed density 1.4-1.7 g/cm3 or from porous particles of size 56-160 mcm, with pores size in particles 0.3-5.0 mcm, allows specific surface area 0.1-0.2 m2/g, packed density 1.8-2.4 g/cm3 and fluidity 7-12 g/s or from porous particles of value 160-450 mcm, with pores size in particles 0.3-5.0 mcm, allows specific surface area 0.15-0.25 m2/g, packed density 1.8-2.7 g/cm3 and fluidity 8-14 g/s.
EFFECT: it is provided receiving of powder with defined structural and processing characteristics.
10 cl, 3 dwg, 1 tbl, 1 ex
SUBSTANCE: invention can be used for electrochemical isolation of metal chosen from the group consisting of copper, tin, manganese, zinc, nickel, chrome and cobalt, from solutions, containing metal ions. Cell contains anode chamber, cathode chamber allowing falling cathode layer in the form of growing metal balls and separated from the anode chamber by means of electrically isolating diaphragm and vertical external pipeline for passing of upstream of metal balls and electrolyte, directed for feeding of cathode layer. At least one ejector located inside external pipeline nearby its foundation or nearby the bottom of cathode chamber or on the outside of the cell in hydraulic communication with the bottom of cathode chamber is provided for installation of metallic balls and electrolyte upstream. Cell is described by process continuity of metal extraction, more simple for control and operation.
EFFECT: providing of process continuity of metal extraction.
17 cl, 5 dwg
SUBSTANCE: invention relates to methods for obtaining nanoparticles of platinum metals - iron alloy. The method includes electrochemical dissolution of iron - platinum metal alloy, at controllable value of anode potential from +0.1 to +0.6 V with production of nanoparticles of the size of 0.5 - 10 nanometers in the form of non-dissolved deposit with of iron content of up to 40% from the sediment mass. At electrochemical dissolution of the iron-platinum metal alloy with the content of platinum metal of up to 10 wt % in sulphate-chloride dissolvent, anode potential is set to a value of +0.1 V to produce nanoparticles of the size of 5-10 nanometers with the iron content of up to 40 % from the sediment mass of the deposit, and to a value of +0.6 V to produce nanoparticles of the size of 0.5-5 nanometers with iron content of up to 10% from deposit mass. At electrochemical dissolution of iron-platinum-palladium-rhodium-iridium alloy with platinum content of 2.5%, palladium content of 2.5%, rhodium content of 2.5% and iridium content of 2.5% from mass of the alloy, anode potential is set to a value of +0.6 V to produce nanoparticles of the size of 1-5 nanometers with iron content of 10% from the sediment mass. The technical result is the possibility to produce nanoparticles of necessary composition and structure adjusting potential of the anode.
EFFECT: chances to obtain nanoparticles of necessary structure and composition by adjusting anode potential value.
4 cl, 4 ex
SUBSTANCE: proposed method comprises anodic oxidation of melt in acid electrolyte at application of electric current. Note here that said anodic oxidation is carried out in acid electrolyte containing 150 g/l of H2SO4+50 g/l HCl. Applied direct electric current features density of 250-300 mA/cm2. Application of said current is conducted at 20-40°C.
EFFECT: notable increase in anodic oxidation rate.
3 tbl, 2 ex
SUBSTANCE: method involves using a double-chamber electrochemical module containing sulphuric acid solution, having two cation-exchange membranes and a lead anode in the rear chamber. Each of the chambers of the electrochemical module contains sulphuric acid solution with concentration of 50-200 g/l. Current density on the lead anode is equal to 2.5-7.5 A/dm2. An indicator lead anode is placed in the front chamber, said indicator anode signalling the need to move the sulphuric acid solution from the rear chamber into the front chamber and fill the rear chamber with fresh sulphuric acid solution, wherein the surface area of the indicator anode is equal to 0.5-2% of the surface area of the main anode, and current density thereon is equal to that on the main anode.
EFFECT: method prevents decomposition of the main lead anode and minimises consumption of sulphuric acid used to prepare and replace solutions in both chambers of the module.
1 dwg, 2 ex
SUBSTANCE: proposed method comprises dissolving wastes in acid electrolyte by applying AC electric field thereto. Dissolving is performed in nitrate or sulphate electrolyte on applying half-wave asymmetric AC industrial-frequency current and on using second electrode made from tantalum or niobium plates. Note here that anodic dissolution is carried at acidity of nitrate electrolyte at the level of 200-250 g/l HNO3, while that of sulphate electrolyte making 150-200 g/l H2SO4 at 20-40°C and current of at least 1 kA.
EFFECT: increased process rate, better ecology.
3 cl, 3 tbl, 3 ex
SUBSTANCE: method includes electrolysis from electrolyte made of purified sulphate solutions with insoluble leady anodes. Additionally electrolysis is implemented at electrolyte circulation with keeping of pH 4.5-5.5; temperature is in the range 59.5-65°C and concentration of nickel ions (II) in the initial electrolyte 100-110 g/dm3, and in the waste 40-50 g/dm3. Concentration of nickel ions (II) in the initial electrolyte is kept by means of inlet 20-48% of waste electrolyte from circulation system. Uninterruptedly it is measured pH of solution and it is automatically kept during the electrolysis process by means of acidity adjustment. Electrolyte is fed into interelectrode spacing on surface of bath through graduated branch pipes. In the capacity of cathode there are used reusable cathodes - matrix, implemented from titanium.
EFFECT: method reduction in price, increasing of engineering-and-economical performance of electrolysis process.
4 cl, 1 tbl
SUBSTANCE: invention relates to structures of diaphragm cells for electrolytic extraction of nickel from water solutions, particularly anode kettle. Anode kettle for electro-separation of non-ferrous metals by means of electrolysis in bath, allowing cathode chamber with catholyte, containing rigid-jointed framework, diaphragm bag, insoluble anode, contrivance for prevention of anode touch to diaphragm bag, facility for anolyte withdrawal and extracted on anode gaseous substances ensured by depression, implemented in the form of connecting pipe with inner diametre 5-12 mm, rigid in framework of anode kettle to bottom hole edge of connecting pipe is at the distance h from top edge of the kettle, defined from the formula: h=a+b, where a - distance between kettle edge to the level of catholyte in bath; b - level difference between catholyte and anolyte. Device preventing touch of anode with diaphragm bag is implemented in the form of grid from vertically located rods of thickness k=10-15 mm, manufactured from dielectric material and fixed on two horizontal abutment blocks with interval equal to 10*k.
EFFECT: providing of exclusion of anode touch to diaphragm bag and defined level difference between catholyte and anolyte.
1 dwg, 1 tbl
FIELD: non-ferrous metallurgy; production of cathode nickel from sulfide copper-nickel raw material.
SUBSTANCE: proposed method includes floatation separation of converter matte into copper and nickel concentrates, oxidizing annealing of nickel concentrate, reduction of nickel monoxide, leaching-out of reduced nickel monoxide, cleaning the leaching-out solutions in succession from iron, copper, cobalt and electrical extraction of nickel. Electrical extraction of nickel is carried out in the electrolysis baths provided with anode cells from nickel electrolyte containing 40-85 g/l of sulfate and no less than 45 g/l of chloride for production of electrolyte nickel of required grades; gas-and-liquid mixture thus formed is removed from anode cell and is separated into gas phase mainly containing chlorine which is used for chloride leaching-out of reduced nickel monoxide and acid anolyte which is used for diluting the leaching-out solution prior to cleaning from copper.
EFFECT: enhanced efficiency.
2 cl, 2 dwg, 2 tbl, 2 ex
FIELD: metallurgy, possibly processes related to electrolytic refining of nickel for making up its deficiency in solution, production of nickel salts.
SUBSTANCE: method comprises steps of preliminarily disintegrating scrap metallic nickel and cuttings of cathode nickel till size 5 - 20 mm; electrolytic dissolving of it by passing alternating current with current intensity 2500-20000 A/m2 in sulfur acid solution, 130 - 200 g/l.
EFFECT: short time periods for preparing additional volumes of solution used for nickel refining.
1 tbl, 12 ex
FIELD: methods of manufacture of cell diaphragm components for electrolytic extraction of metals from aqueous solutions.
SUBSTANCE: diaphragm component formed from diaphragm cloth has at least one side surface with vertical edges and horizontal edges; at least one edge has electric insulating section of preset width; specific electrical resistance of this section is lesser than electrical resistance of central section by 5 times.
EFFECT: reduced usage of materials; continuous operating cycle; improved quality of cathode metal.
17 cl, 11 dwg, 1 tbl,, 3 ex
FIELD: non-ferrous metallurgy, namely electrolytic production of nickel.
SUBSTANCE: method of electrolytic production of nickel by electrolysis of nickel from nickel electrolytes at adding surface active matter such as sulfonates (alkan- and alkyl aromatic acids salts) is realized at using as surface active matter "Sulphonol-P" (mixture of sodium salts of alkyl benzenesulfonic acids on base of n-paraffins CnH2n+1-C6H4-SO3Na where n = 10 - 13) supplied as aqueous solution with concentration 5 -10 kg/m3 to preliminarily cleaned from impurities nickel electrolyte (catholyte). When electrolysis of nickel is realized at using sulfate-chloride electrolyte and soluble nickel anodes, said mixture is supplied to electrolyte in quantity providing concentration of surface - active matter in it 4 - 5 g/m3. When electrolysis of nickel is realized at using sulfate electrolyte and non-soluble nickel anodes above mentioned mixture is supplied to electrolyte in quantity providing concentration of surface active matter in it 40 - 60 g/m3.
EFFECT: lowered consumption of surface-active matter, simplified technique of preparing and metering surface-active matter, reduced separation of nickel aerosols to air of working zone of electrolysis bathes, increased cathode electric current yield.
1 tbl, 19 ex
SUBSTANCE: proposed device comprises casing to accommodate cells connected in series and composed of cathode, anode, gastight membrane arranged there between, pump to circulate alkaline electrolyte, tanks with alkaline electrolyte, water feed system, device to separate oxygen from water and alkali vapors and device to separate hydrogen from water and alkaline vapors. Anode of every cell is composed of screen tube while cathode is composed of hollow cylinder made from porous water-repellant material. Note here that anode and cathode are located close to gastight membrane to form cathode gas chamber between outer side of cathodes and casing connected with hydroseal chamber, alkaline electrolyte tank and device separating hydrogen from water and alkali vapors. Cell anode chambers are connected with heat exchanger and alkaline electrolyte tank communicated with device separating oxygen from water and alkali vapors and water feed system.
EFFECT: power savings, higher efficiency, reliability and safety.
5 cl, 2 dwg