The way hydroxide nickel (ii)
(57) Abstract:The invention relates to the field of producing compounds of Nickel, in particular to technology hydroxide Nickel (II) used for current sources, for example, in the composition of the active mass of the positive electrodes of alkaline batteries. The invention consists in the method of producing Nickel hydroxide (II) for current sources, including the preparation of the initial solution of the hydroxide of alkali metal salt of Nickel (II) and barium hydroxide, mixing them, the precipitation of the hydroxide of Nickel (II) separating the mother liquor, sludge treatment with alkali in an autoclave at a temperature of 130-200oWith, washing the precipitate and drying. The alkali treatment is carried out at the concentration of hydroxyl ions in the liquid phase of the pulp, 0.05-0.3 g-ion/liter Washing of the precipitate is carried out in three stages: the first stage of water in the second stage with a solution of barium hydroxide with a concentration of 2-6% and in an amount to provide a mass ratio of the solution to precipitate (1-2):1, and in the third stage, again with water. The method is simple, eliminates the time-consuming and energy-intensive operation of the sludge drying before washing. The product reduces the content of water-soluble impurities anions SO42-Cl-. 2 C.p. STI to technology hydroxide Nickel (II), used for current sources, for example, in the composition of the active mass of the positive electrodes of alkaline batteries.Prior art
The known method hydroxide Nickel (II) used for alkaline batteries (M. A. Dalian, Century Century novoderezhkin and F. F. Tomaszewski "Manufacture of electric accumulators", M., "Higher school", 1977, pp. 260-277). The method involves the preparation of initial solutions of sodium hydroxide, sulfate Nickel (II) and barium hydroxide as adjuvants and the mixture of them. The precipitate is separated by filtration, then is subjected to the first drying, washing from sulfate ions, the second drying and grinding. The disadvantages of the method are its duration and large energy costs associated with the need to double-dried product obtained.A method of obtaining Nickel (II) hydroxide, which includes the injection of a solution of Nickel sulphate in alkaline solution, ochiltree and drying the precipitate, washing from sodium sulfate, re-drying, treatment with alkali boiling, washing with water and final drying (ed. mon. SU 51380, 1937). Three drying makes the process very long and labor - intensive.Famous t is yuusei Supplement containing barium ions. This is followed by precipitation, separation of the mother liquor, centrifuge sludge is first dried to a certain moisture, washing away impurities and the second drying. After first drying the resulting paste is injected with a solution containing ions of cobalt (patent RU N 2138447). The method has the same drawbacks as in the previous case. In particular, each of the two stages of drying lasts about 24 hours.The invention
The proposed method significantly reduces the duration of the process and reduce the cost of obtaining hydroxide Nickel (II) with a simultaneous increase of its quality.The way hydroxide Nickel (II) current sources includes the preparation of the initial solution of the hydroxide of alkali metal salt of Nickel (II) and barium hydroxide (adjuvants), mixing them, sedimentation and separation of the mother liquor, subsequent washing of the precipitate and drying. When this residue before washing processed with alkali in an autoclave (hydrothermal treatment). The treatment is carried out at T=130-200oC, maintaining the concentration of hydroxyl ions in the liquid phase of the pulp 0.1-0.5 g-ion/literWashing the precipitate preferably conducted in three stages: the first stage of water in the second stage solution and in the third stage, again with water.In the first stage of washing separates the main mass of the soluble salts, the impurity metals in the second stage, additional extraction in solid phase remaining in the liquid phase in the pores of the sediment sulfate ions due to the formation of low-solubility of barium sulfate in the third stage - goatmilk sludge from cations of barium and soluble salts.The positive effect of hydrothermal processing on the proposed method is called with the result of this processing by changing the composition and structure of the sediment and the resulting properties (specific volume, the electrochemical capacity, the content of impurity anions included in the structure of the sediment in the form of basic sulfates of the type (3-6)Ni(OH)2With NISO4and the basic chloride of type (1-3)Ni(OH)2NiCl2and also in the form of soluble sulfates and chlorides, adsorbed to sediment). Presumably, this change occurs by the following mechanisms: the ordering patterns of sediment (transition from x-ray amorphous state to crystalline), collective recrystalization and dehydration emitting adsorbed salts and water and basic hydrolysis of salts emitting structural sulfate and chloride ions in the liquid phase.the ü the content of water-soluble impurities anions SO42-and Cl-in the hydroxide Ni (II) and its specific volume, and improve the electrochemical capacity of the product. In addition, obtaining hydroxide Ni (II), according to the invention, reduces the technological process by eliminating the operation of drying before washing the hydroxide precipitate Ni (II) from impurities.Information confirming the possibility of carrying out the invention
For the deposition of Nickel hydroxide (II) the known methods has prepared the following solutions:
the sodium hydroxide solution with a concentration of 26.5%, the specific gravity of the solution 1295 kg/m3at T=15oC;
a solution of Nickel sulfate (II) with a concentration of 15.5%, the specific gravity of the solution 1175 kg/m3at T=15oC;
a solution of barium hydroxide (activator) with a concentration of 4%, the specific gravity of a solution of 1100 kg/m3at T=70oC.In a reactor with a capacity of 1.2 m3equipped with a mechanical stirrer and a heater, poured the prepared solution of sodium hydroxide in a volume of 150 liters and heated to 50oC. Then with stirring for 1 hour the reactor was simultaneously filed a pre-warmed to 50oC solution of Nickel sulfate and 75oC solution of barium hydroxide in quantities 460 l and 25 l of sootvetsvenno and determined the content of sodium hydroxide in the liquid phase, which must be at the level of 4-10 g/l In these conditions the deposition it was 6.2 g/L.After the deposition of the slurry with a temperature of 60oC sent to the filtering centrifuge, in which the separated mother liquor from the precipitate. Pressed on the centrifuge sludge with a moisture content of 15-20% was collected in tank reulator V=1 m3where filed an aqueous solution of sodium hydroxide with a concentration of 0.2 g-EQ/l to establish the ratio of T:W=1:(5-6). After stirring for 10 minutes, took away the pulp sample and determined the concentration of hydroxyl ions in the liquid phase, which under these conditions amounted to 0.18 g-ion/l Then the slurry from the tank-repulper pump filed in the autoclave (V=0,385 m3) equipped with stirring and heating devices. In the autoclave spent processing the pulp with alkali at T=170oC for 1 hour.After treatment with alkali slurry of Nickel hydroxide was cooled to 80-90oC and transferred into the supply tank (V=1 m3) before separating the solid and liquid phases. Separating the mother liquor from the precipitate conducted on the filtration centrifuge, where filed cooled to 70-80oC the pulp from the supply tank.Pressed on the centrifuge sludge with humidity is pout stage wash led purified water at the rate of 2 kg per 1 kg of dry sludge, in the second stage, a solution of 4% barium hydroxide in the amount of 1.5 kg of solution per 1 kg of dry sediment and the third stage is again purified water at the rate of 1.5 kg per 1 kg of dry sediment.The washed sludge with a moisture content of 15-20% from the centrifuge was transferred to vibrating dryer, where he spent his drying at T=120oC to a moisture content of less than 2%. The dried product was analyzed on the performance of the regulated requirements hydroxide Nickel (II) used for the manufacture of current sources. The results of physico-chemical control of the product obtained had the following characteristics: mass fraction of the sum of Nickel and cobalt - 57,8%, the oxide of Nickel is absent, the mass fraction of barium, related to the mass fraction of the sum of Nickel and cobalt - 2,1%; mass fraction of the sum of the anions Cl-and SO42-(free), related to the mass fraction of Nickel and cobalt - 0,34%, the amorphous phase is missing, the specific volume is 0.65 cm3/g, electrochemical capacitance - 0,166 a/h 1,Getting hydroxide Ni (II) proposed way faster and cheaper process, as it eliminates lengthy and energy-intensive operation of the sludge drying before washing hydroxide Ni (II) from impurities. In addition, the final product is Holocene hydroxide Nickel (II) current sources, including the preparation of the initial solution of the hydroxide of alkali metal salt of Nickel (II) and barium hydroxide, mixing them, the precipitation of the hydroxide of Nickel (II) separating the mother liquor, washing the precipitate and drying, characterized in that before washing the residue is treated with alkali in an autoclave at a temperature of 130-200oC.2. The method according to p. 1, characterized in that the alkali treatment is carried out at the concentration of hydroxyl ions in the liquid phase of the pulp, 0.05-0.3 g-ion/liter3. The method according to p. 1, characterized in that the washing of the precipitate are in three stages: the first stage of water in the second stage with a solution of barium hydroxide with a concentration of 2-6% and in an amount to provide a mass ratio of the solution to precipitate (1-2):1, and in the third stage, again with water.
FIELD: process engineering.
SUBSTANCE: invention relates to device and method of producing compounds by precipitation of solid substances. Proposed device comprises reactor provided with inclined settler. Proposed method comprises mixing initial substances in reactor, precipitation of compounds in reaction zone, partial separation of mother leach from precipitated product in inclined settler, separation of product suspension, its filtration and drying. Invention covers also mixed powder of nickel-cobalt hydroxide with WET-surface of less than 20 m2/g and impact density exceeding 2.4 g/cm3.
EFFECT: suspension with concentration exceeding stoichiometric one.
29 cl, 13 dwg, 5 ex
FIELD: power engineering.
SUBSTANCE: method to produce a composite NiO/C material containing 15-60% NiO and representing crystallites β-NiO evenly distributed on a carbon carrier surface with the average size of 2-5 nm, is based on production of NiO nanoparticles as a result of electrochemical oxidation and destruction of two nickel electrodes in solutions of alkaline metal hydroxides with concentration of 2 mole/l under action of AC current with frequency of 50 Hz at average value of current referred to a unit of electrode surface area making 0.3-1.5 A/cm2, with simultaneous deposition of produced nickel oxide nanoparticles onto the carbon carrier, subsequent filtration of the produced suspension, washing of composite by distilled water and its drying at 80°C for 1 hour.
EFFECT: invention makes it possible to increase quality of produced material due to absence of admixtures and to reduce costs for its production.
SUBSTANCE: invention can be used in chemical industry. The method of producing nickel (II) hydroxide involves treatment of an acidic solution of nickel (II) sulphate in two steps, at the first step with ammonia water to pH 4-4.5, at the second step with sodium hydroxide to pH 11-12. At the second step, the process is carried out by feeding the suspension from the first step into the sodium hydroxide solution. Further, impurities are washed off from the residue in an ascending stream with variable hydrodynamic conditions. The residue is then pressed and dried.
EFFECT: invention increases purity of the product and uniformity of its grain-size distribution.
3 cl, 3 tbl, 3 ex
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.
SUBSTANCE: method comprises production of the nickel oxide powder from metal nickel electrodes by electrolysis in basic solution of sodium hydroxide. Process is executed at temperature 20-30°C upon simultaneous action on the electrodes of current with frequency 20 Hz. At that electrolysis is performed at asymmetrical alternating current with current density of anode and cathode half cycle 2.5 A/cm2 and 1 A/cm2, respectively, and at action on the electrodes of the ultrasound radiation with frequency from 150 to 300 kHz.
EFFECT: production of ultra-micro-dispersed powder of nickel oxide suitable for use during catalitic production of nano-carbon materials with maximum production of the target product, decreasing of power consumption.
FIELD: electrical engineering.
SUBSTANCE: invention relates to electrical engineering, namely to production of aqueous paste of nickelous hydroxide. As starting material used is alkaline industrial effluents directly from section of producing metal ceramic nickel oxide electrodes containing admixture KOH, K2SO4 and hydrate suspension, which are settled, then suspension is washed and filtered.
EFFECT: invention enables to obtain fine highly active fraction of nickelous hydroxide with simplification of method.
4 cl, 2 ex
SUBSTANCE: invention relates to electrochemical production of active forms of nanoparticles of metal oxides. Electrochemical method of producing nano-sized structures of nickel (II) oxide involves oxidation of anode in ionic liquid in an air atmosphere. Nickel anode and cathode are used. Oxidation is performed at temperature 20-25 °C for 2-20 minutes, with density of direct current of 5-10 mA/cm2 or at constant potential of 2.3-5 V. Ionic liquid is preferably with addition of distilled water or propylene glycol.
EFFECT: invention ensures production of highly ordered nano-sized structures.
4 cl, 5 dwg, 5 ex
SUBSTANCE: invention relates to a method of producing crystalline nanopowders of metals with the size of crystallites of less than ≤ 10 nm and can be used in chemical industry, for production of intermediate products for fine ceramic materials. Synthesis is carried out in a water-organic medium using as sources of metal nitrates, chlorides or acetates. For formation and stabilization of sol used are acetylacetone-alcoholic solutions of N,N-dimethyloctylamine, hexamethylene tetramine or monoethanolamine. As a complexing agent used is acetylacetone. Obtained sol through a jet nozzle is dispersed into liquid nitrogen, where at the cooling rate > 30° cryogranulating takes place. Produced granules are subjected to vacuum-sublimation drying to form a cryo-airgel, which is then annealed at 500 °C in air for 3 hours.
EFFECT: proposed method provides technologically effective and environmentally acceptable method of producing nanocrystalline of metal oxides.
4 cl, 8 dwg, 1 tbl, 6 ex
SUBSTANCE: method of producing nanodispersed metal oxides involves forming a reaction mixture by introducing metal and carbamide nitrates into the aqueous medium in a stoichiometric ratio. The reaction medium is exposed to microwave radiation. The reaction mixture is formed directly in the reaction volume at the following component ratio, wt %: a mixture of nitrate and carbamide 10-20, water - the rest. The exposure to microwave radiation is carried out with open access to the reaction medium in the reaction volume. The intermediate reaction product is dried at a temperature of, at least, 200°C. The dried product is ground to a particle size of not more than 20 nm. During the grinding of the dried product, a hydrophobizing treatment is carried out in parallel with a hydrophobizing mixture consisting of silanes and silicone oligomers taken in the ratio, wt %: silane 17-33, silicone oligomer 67-83.
EFFECT: complete conversion of metal nitrates to oxides having prolonged resistance to agglomeration, increasing the yield of products, excluding the presence of traces of the original components in the products.
4 cl, 6 tbl, 8 ex