Method of processing natural-origin uranium-bearing ore
SUBSTANCE: proposed method comprises leaching the stock nitric acid solution to obtain suspension, introducing coprecipitator therein at 30-50°C and mixing. Then, clarified solution is separated from insoluble residue and directed for extraction. Said coprecipitator represents fresh solution of copolymer of acrylamide and chloride trimethyl ammonium ethyl acrylate of molecular weight of 3-15 millions with low charge density. Copolymer is introduced to concentration of 5.95-11.9 mg/l of insoluble residue. Prior to separation of clarified solution from insoluble residue settling is performed for 30-40 minutes.
EFFECT: lower processing costs.
3 cl, 1 dwg, 1 tbl
The invention relates to the processing of uranium-containing raw materials of natural origin, which includes impurities of various substances (mainly metals).
At dissolution (leaching) of uranium-containing materials, which comprises the admixture of various substances in solutions of nitric acid insoluble residue. In the process of extraction refining insoluble residues contribute to the formation of nerasseivayushchee emulsions (jellyfish) of the aqueous phase with the extractant - 30%TBP in a hydrocarbon diluent, which leads to disruption of the extraction process. Therefore, if the extraction production is focused on the processing of solutions that do not contain a solid phase, insoluble residues should be removed from solutions. It uses a variety of techniques, most often, sedimentation, filtration and/or centrifugation.
For example, in the method of chemical processing of natural uranium concentrate (NUC) [RF Patent №2398036, IPC SW 60/02, publ. 27.08.2010] source uranyl nitrate solution was prepared by dissolving NUC in nitric acid solution and separated from the resulting insoluble residue by decantation.
The method of processing of concentrated natural uranium oxides [RF Patent №2323883, IPC C01G 43/01, publ. 10.05.2008] includes leaching of uranium kontsentrirovano the th nitric acid at elevated temperature and separating the aqueous phase from the insoluble residue by filtration through a polyester cloth, PE-100 after settling for several hours or by centrifugation.
Closest to the claimed method is the processing of uranium raw materials, including leaching of uranium-containing raw material with a solution of nitric acid and separating the resulting slurry into solid and liquid components [Kozyrev, A.S., Ciceron YEAR, Ryabov A.S., Shamin, V., Mikhailova N.A., Skuratov MV intensification of the processes of separation of highly concentrated solutions of uranyl and fine suspended solids. Bulletin of the Tomsk Polytechnic University. - 2007. - 311 so. No. 3. - Page 16-19]. In this way in the nitric acid solution of uranyl nitrate, obtained by leaching (dissolution) of the concentrate in the form U3O8(the impurities are 12% by weight of the sample) with the concentration of uranium 300-450 g/l of nitric acid 0.7 to 3.0 mol/l, enter the primary coagulant cationic type FLOQULAT™ FL 45 in the amount of 100-200 mg/l for the destabilization of the colloidal system. Then, the suspension is injected secondary cationic flocculant FO 4140 PWG in the amount of 5-10 mg/l for the formation of macrolophus. The process is carried out at a temperature of 30-50°C. After injection of coagulant and flocculant insoluble residue (mass which does not exceed 0.6% by weight of the sample) was separated from solution by filtration, to obtain a transparent solution of uranyl nitrate, suitable for the extraction process. This method is chosen for the prototype.
The disadvantages of this method to the convicts who are stated in the process of separating the insoluble residue from the suspension time-consuming because it requires the use of several types of coosawatee and additional costs for instrumentation process.
Object of the invention is the intensification of the process of separation obtained in the leaching of uranium feedstock suspensions clarified water and the insoluble residue, namely, an increase in the speed of lightening suspension and reducing the amount of insoluble residue.
The set task is solved by the fact that in the method for processing of uranium-containing raw materials of natural origin, including leaching solution of nitric acid to obtain a suspension, an introduction to the suspension of shoesadidas at a temperature of 30-50°C, stirring, separating the clarified solution from the insoluble residue and the extraction solution, the suspension is injected freshly prepared solution of a copolymer of acrylamide and trimethylammoniumchloride chloride with a molecular mass of from 3 to 15 million, with a low charge density. Copolymer of acrylamide and trimethylammoniumchloride chloride is introduced into the suspension to its concentration 5,95 is 11.9 mg/g of insoluble residue. The Department clarified solution from the insoluble residue is carried out after sludge within 30-40 minutes.
Figure 1 shows graphs of the time full oswell is of the slurry from the concentration of coosawatee, used in the claimed method and the prototype.
In order to intensify the process of separation obtained in the leaching of uranium feedstock suspensions clarified water and the insoluble residue studies have been conducted on the selection of coosawatee suitable for separating the insoluble residue from the suspensions obtained by the leaching of uranium-bearing materials, and optimal conditions of separation.
As source material used peroxide uranium UO4·2H2O (piroxicamnova acid (H2UO5·H2O). The chemical composition of this raw material is characterized by a significant content of the following impurities: iron, aluminum, calcium, sulfur, molybdenum (number of impurities 30% by weight of the sample).
Suspension of uranyl nitrate was obtained by dissolution of the feedstock in the solution of nitric acid. The dissolution process was carried out at a temperature of 60-95°C with constant stirring system with a mechanical stirrer at 1000 rpm the resulting suspension had a characteristic brown-orange color of ferric hydroxide on the background of yellow-green highly concentrated solution of uranyl nitrate. The uranium concentration in the aqueous phase of the resulting suspension was in the range of 200-450 g/l, the concentration of free nitric acid of 0.1-1 mol/l Insoluble residue was 1,53% of mA the son of a sample.
The resulting suspension was divided into three parts: one control, the rest is added freshly prepared solutions:
1. In the first series of experiments the polymer complex (high charge density) on the basis of diallyldimethylammonium chloride in the form of vinylpyridine (activation of the polymer shown by formula 1), then the cationic flocculant (low charge density), which is a chlorinated polymer of an organic Quaternary ammonium bases, in the amount of 5-10 mg/l In the experiments of this series are similar to the prototype used a solution of coagulant VPK-402 and flocculant FO 4140 PWG, possessing the above characteristics.
where R is a hydrocarbon skeleton and an inactive functional group
2. In the second series of experiments the solution of a copolymer of acrylamide and trimethylammoniumchloride chloride [(C3H5NO)x-(C8H15NO2Cl)y], where x=57000 11000..., y=57000 11000...with a molecular mass of from 3 to 15 million, with a low charge density (activation is represented by formula 2). In the experiments in this series were used flocculant solution FO 4190, possessing the above characteristics.
To determine the speed of achieving a complete clarification of the suspension was measured optical density of solutions. For full clarification of the suspension took the time what I when the optical density of the solution became constant.
Experiments were performed as follows. Immediately after the dissolution of the original uranium-containing raw materials each piece resulting suspension was mixed and divided into 13 equal portions of 50 ml each.
From the first portions of each part of the resulting suspension immediately after separation (i.e., without exposure of suspension) were selected from the top 25 ml of suspension, the sample was mixed and measured the optical density of the sample fotoelektrokalorimetry. Then at set intervals of time(5, 10, 15, 20, 30, 40, 60, 90, 120, 150, 180 minutes in a day) conducted similar measurements with the other portions.
During the experiments it was noted that in the control part of the suspension is approximately 1/3 of the volume of the insoluble residue during the day, defended and represented very mobile, easy vspuchivanie sediment, 2/3 of the volume of the insoluble residue formed by solution sedimentation-sustainable system that 3-4 days Svetlanas 25-30%.
It was also noted that with the introduction of coosawatee all insoluble residue in the system almost immediately becomes flaky. The combined use of coagulant VPK-402 and flocculant FO 4140 reduces the time of the full clarification to 2.5 hours. The introduction of the flocculant FO 4190 allows you to reduce the time of the full clarification of the solution to 30 minutes.
The graphs presented in figure 1 show that with the introduction of the flocculant FO 4190 (claimed invention) the speed of lightening suspension is higher than with the introduction of the coagulant VPK-402 (prototype)at any concentration of shoesadidas and despite the fact that in the method according to the prototype to improve process efficiency and reduce the dosage of coagulant to the minimum number required for destabilization of the suspension system further added flocculant FO 4140.
During experiments it was found that the smallest time clarification of the suspension corresponds to the concentration in the system flocculant FO 4190 equal 95-110 mg/l, which is 5,95 is 11.9 mg/g of insoluble residue.
Obtaining a minimum amount of insoluble residue leads to an increase in yield of purified solution and contributes to the intensification of the process of separation obtained in the leaching of uranium feedstock suspensions clarified water and the insoluble residue. In the process of conducting experiments have been marked changes in volume of the thick part of the suspension depending on shoesadidas and exposure time. The measurement results are shown in table 1.
|The volume change novellen the second part of the suspension depending on shoesadidas|
|The concentration of nitric acid, mol/l||The volume of the thick part of the suspension, % vol.|
|10 min||30 min|
|Without the use of coosawatee||Concentration VPK - 402 in the system of 100 mg/l and FO 4140 PWG 5 mg/l||The concentration FO 4190 PWG in the system of 100mg/l||Without the use of coosawatee||Concentration VPK - 402 in the system of 100 mg/l and FO 4140 PWG 5 mg/l||The concentration FO 4190 PWG in the system of 100 mg/l|
The data presented in table 1 allow us to draw the following conclusions. The introduction of a copolymer of acrylamide and trimethylammoniumchloride chloride allows you to receive less than the introduction of polymer complex on the basis of diallyldimethylammonium chloride and optionally chlorinated polymeric organic Quaternary ammonium bases, the volume is not clarified part of the suspension. And for achieving this result requires nitric acid of lower concentration.
After separation of the suspension into clarified water and the insoluble residue, the insoluble residue was separated from the solution by filtration. The measurement of the velocities of the filter showed that the combined use of coagulant VPK-402 and flocculant FO 4140 allows you to increase the filtration rate from 20 to 75 ml/min, and added to a suspension of flocculant FO 4190 increases the speed to 110 ml/min
After separation of the suspension, the resulting solution was sent to extract the Y. During the process of education nerasseivayushchee emulsions were observed.
The experiments prove that the use as shoesadidas separating suspensions solution (low charge density) [- (C3H5NO)x-(C8H15NO2Cl)y], where x=57000 11000..., y=57000 11000...with a molecular mass of from 3 to 15 million resulting from the copolymerization of acrylamide and trimethylammoniumchloride chloride, reduces the amount of time the bleaching solutions and ensures the formation of a smaller amount.
Implementation of the proposed method of separation of insoluble residues from suspensions of uranyl nitrate will significantly reduce the time of settling and filtration, which in turn will have a positive impact on cost of capital and, consequently, will reduce the cost of processing the entire circuit as a whole.
1. Method for processing of uranium-containing raw materials of natural origin, comprising leaching the material with a solution of nitric acid to obtain a suspension, an introduction to the suspension of shoesadidas at a temperature of 30-50°C, stirring, separating the clarified solution from the insoluble residue and the direction of the solution on the extraction, characterized in that the suspension is as shoesadidas impose a freshly prepared solution of copolymer acrylamide of trimethylammoniumchloride chloride with a molecular mass of from 3 to 15 million and with a low charge density.
2. The method according to claim 1, characterized in that the copolymer of acrylamide and trimethylammoniumchloride chloride is introduced into the suspension to its concentration 5,95 is 11.9 mg/g of insoluble residue.
3. The method according to claim 1, characterized in that before separating the clarified solution from the insoluble residue conduct advocacy for 30-40 minutes
SUBSTANCE: composition contains a compound of formula (I)
as a complexing component, where R is a C1-C12 alkyl, in percentage content of 1-99%, and the rest of the polymer matrix is a macroporous spherical granular copolymer of styrene with divinyl benzene LPS-500 with granule size of 40-200 mcm.
EFFECT: high sorption capacity with respect to Mo-99.
SUBSTANCE: invention refers to metallurgy, particularly to hydrometallurgical methods of processing and deactivation of radioactive waste at rare metal production. The method includes hydro washing away of spent melt of saline spraying filter (SSF), the chlorination process of loparit concentrates, treatment of produced suspension with alkaline reagent, mixing with iron containing shop flush waters, separation of radioactive sediment from the mother solution and transporting of radioactive sediment into a special waste storage (SWS). Prior to treatment with the alkaline reagent the suspension, produced after hydro washing away of spent melt SSF, is mixed at a ratio 1:(0.8-1.2) with the solution, containing 250-300 g/dm3 chlorides of alkali metals, and is heated to 85±5°C. With the use of solution of sodium hydroxide as the alkaline reagent treatment of the suspension is performed to pH 2.0+0.5, then this solution is held for 0.5+0.1 hr, then solution of high molecular flocculant- hydrolysed oilacrilamid - is introduced and is held without mixing for 2.0±0.5 hrs. After that the thickened part of the suspension is fed to a nutsch-filter, the produced sediment - rare metal concentrate - is dried, tempered and transfered to chlorination of source loparit concentrates. Filtrate is combined with clarified portion of the suspension, heated to 80±10°C and treated with solution of sodium hydroxide to pH 12.0±0.5. Produced oxihydrate pulp is held at 80±10°C for 1.0±0.5 hrs and is fed to a filter-press-I; the extracted radioactive sediment is washed out at the filter-press-I 3-4 volumes of water, and process water is merged with shop flush water. The washed out sediment is blown out with a compressed air at the filter-press-I, then unloaded and transported to SWS, while mother solution is mixed at a ratio of 1:(10-20) with iron containing shop flush water. Produced radioactive chloride solution is heated to 80±10°C and treated with solution of sodium hydroxide to pH 12.0±0.5, the resulted pulp is held at 80±10°C and pumped to a filter-press-II with production of deactivating solution, which is discharged to a shop drainage, and with production of sediment; the latter is merged with the sediment - rare metal concentrate, extracted out of suspension after dissolving of the spent melt SSF; the said sediment is heat treated and partially neutralized, then dried, tempered and transferred to chlorinating in saline chlorinators together with the source loparit concentrate.
EFFECT: upgraded degree of deactivation of solutions and discharge waters and additional extraction of valuable elements.
2 dwg, 1 ex
FIELD: radiochemistry; analytical chemistry.
SUBSTANCE: proposed method consists in treatment of solution containing elements to be separated, diethylene triamine, pentaacetic acid, carbamide or formic acid, extracting agent in form of solution of chlorinated cobalt dicarbollide and polyethylene glycol in organic solvent or solution of cobalt dicarbollide, zirconium slat of dibutyl phosphoric acid and polyethylene glycol in organic solvent. Americian passes into organic solution at higher degree as compared with curium. Proposed method takes into account factor of separation of americian and curium and facilitates the process due to avoidance of salting-out agent.
EFFECT: enhanced efficiency.
4 cl, 2 tbl, 2 ex
FIELD: reprocessing of worked-out equipment, contaminated with radioactive impurities.
SUBSTANCE: claimed method includes deactivation of contaminated equipment in assembly, disassembling, fragmentation, separation of surface-contaminated fragments, deactivation thereof, classification of metal kinds and groups, and acceptance of mechanical and physical alterations. Fragments satisfied to acceptance results are deactivated without changing form and metal structure thereof and separated into fragments for direct application and for technological update. Fragments not satisfied to acceptance results are used as debris of metal radwastes in metallurgy to produce steel and alloys. Method for production of steel and alloys includes batch preparing, additive introducing during melting process and casting of finished metal. Necessary debris amount to produce desired chemical element content in specific grade of steel or alloy is predetermined followed by calculation of dilution coefficient and upper limit value of debris specific activity. Then debris with specific activity of not more than calculated upper limit value is fed in founding as the base metal and/or addition alloy.
EFFECT: simplified and economy reprocessing method; increased metal amount recycled into national economy, and reduced solid radwaste amount.
3 cl, 2 ex
SUBSTANCE: method includes grinding of initial material, cyanide leaching with production of a product solution of gold with mercury admixtures, introduction of a sulfide-containing reagent for mercury deposition, sorption of gold onto activated coal with return of the reuse cyanide solution for leaching, desorption of gold and electrolysis of gold from a strippant. The sulfide-containing reagent is introduced in the form of an aqueous solution of a mixture of sodium sulfide and calcium oxide at their mass ratio of 4.3-4.4 per 900-1100 wt parts of the reuse cyanide solution. After separation of mercury in the form of a sparingly soluble residue, the suspension is separated to produce a clarified solution, from which the gold is adsorbed onto activated coal.
EFFECT: practically complete separation of mercury without negative impact at gold sorption.
4 cl, 1 dwg, 1 ex
SUBSTANCE: invention relates to a method of producing bismuth potassium citrate. Bismuth potassium citrate is obtained by treating bismuth citrate with aqueous potassium hydroxide solution. The method is carried out with molar ratio of potassium hydroxide to bismuth citrate of 1.0-1.5, and with weight ratio of potassium hydroxide solution to bismuth citrate of 0.5-2.0. The product is obtained in form a paste.
EFFECT: simple process and reduced consumption of reactants.
1 tbl, 3 ex
SUBSTANCE: method of noble metal extraction from solid stock comprises dissolving of noble metal and base metals in acid. Noble metal is extracted with the help of substituted quaternary ammonium salts (SQAS). Noble metal can be oxidised and reduced. Said substituted quaternary ammonium salts represent the following form H0-3R4-1NX, where H= hydrogen, R= organic group, N= nitrogen and X= halogen. This method uses, for example, tetramethyl ammonium chloride. Au-SQAS is separated by flushing with solvent. Rh-SQAS is dissolved in acid and oxidised to precipitate the salts, and separated. SQAS is added to filtrate and cooled to precipitate Rh-AQAS to be separated. Rh-SQAS is cleaned before formation of final product. Other metals are separated by boiling the initial acid solution with precipitation of metal salts, cooling and separation. The pulp is separated by dissolution and separation.
EFFECT: simplified extraction.
20 cl, 4 dwg, 4 tbl, 2 ex
SUBSTANCE: method includes dilution of platinum and rhenium by chlorhydric acid, two-staged solution treatment using sodium hydroxide at the first stage with formation of Pt(OH)4 particles and sodium thiosulfate at the second stage with formation of ReS2 particles. Solution treatment with reagents is performed upon availability of cellulose fibres in it with formation of hard products of reaction in the form of composite materials consisting of cellulose fibres with Pt(OH)4 and ReS2 particles immobilised by them at their chemical deposition. Extraction of composite materials from liquid phase at stages is performed using pressure flotation method.
EFFECT: reducing reagents consumption, simplifying process, providing possibility of process performance in continuous mode.
4 cl, 1 dwg, 3 ex
SUBSTANCE: proposed method comprises REM and phosphorus leeching by sulfuric acid solution to obtain leaching solution and insoluble residue. Said insoluble solution is processed by calcium compound to pH over 5. PEM concentrate is extracted from said solution by crystallisation and fed to REM and phosphorus leaching stage. Prior to leaching phosphogypsum is subjected to flushing with water to obtain flushing solution containing REM and phosphorus. Said insoluble residue is flushed before processing by calcium compound. Obtained flushing solution is processed by calcium compound to produce pulp with pH not over that of REM phosphate precipitation beginning and combied with said flushing solution. REM is sorbed by cation exchangers and separated to desorb REM therefrom to produce desorbent and recovered cation exchanger. Said recovered cation exchanger is sent to REM sorption while desorbent is sent to REM concentrate production stage. Phosphorus and associated impurities are deposited from sorption mother pulp. Obtained pulp is separated in residue to be recovered and water phase to be used as circulating water.
EFFECT: higher efficiency lower loses.
12 cl, 1 dwg, 3 ex
SUBSTANCE: invention relates to production of high-strength inorganic pigments which can be used to produce paint materials. The method of producing an iron-calcium pigment involves neutralisation of iron-containing spent solutions, containing sulphuric acid, with a calcium-containing reagent with deposition of a precipitate, filtration and drying the precipitate. The iron-containing spent solution used is waste water from abandoned deposits of iron-copper-zinc sulphide ores containing iron (III) sulphate and sulphuric acid. The waste water is neutralised until achieving reaction mixture pH of 4-5.
EFFECT: simple process and recycling of under-waste dump and quarry water from spent complex deposits.
2 cl, 2 ex
SUBSTANCE: invention relates to a method of producing an anticorrosion pigment containing iron phosphate. The method involves adding phosphoric acid solution to iron (II) sulphate solution and neutralising the obtained solution with a product containing amine groups. Neutralisation is carried out until pH 5.5-8 is achieved and a precipitate is obtained. The precipitate is then filtered, washed and dried. The product containing amine groups used is polyethylene polyamine and the precipitate is dried at 50-65°C.
EFFECT: improved anticorrosion properties of the pigment and low production cost thereof.
1 tbl, 3 ex
FIELD: process engineering.
SUBSTANCE: invention relates to hydrometallurgy of copper and nickel and may be used for processing sulphate solutions of copper and nickel. Proposed method comprises nickel sulphate crystallisation. Note here that, prior to crystallisation, solution is processed by ammonia water to pH of 4-4.5 at not over 60°C. Nickel sulphate double salt is subjected to isohydric crystallisation with reaction volume cooling to 15-25°C and separation of crystallised double salt from amorphous phase of appropriate component and mother solution. Said separation is carried out in upflow at variable hydrodynamic conditions created by mother solution at its linear rate of 6-8 m/h.
EFFECT: simplified process, decrease fire hazard.
2 cl, 1 tbl, 4 ex
SUBSTANCE: method involves treatment of the sulphide concentrate with aqueous ammonia solution and with hydrogen peroxide solution after heating to obtain a solution containing rhenium and platinum. After treating the sulphide concentrate, an insoluble residue and the obtained solution which contains rhenium and platinum are separated, treated with sulphuric acid to pH 0.0-1.0. The solution is then heated and held and the formed residue of platinum compounds is separated from the rhenium solution.
EFFECT: possibility of separating platinum and rhenium at the step for extracting rhenium from sulphide concentrate.
1 tbl, 1 ex
SUBSTANCE: method involves simultaneous extraction of platinum and rhenium from acid solutions by introducing to the solution of sulphur-containing reducing agent (sodium thiosulfate). Then, deposit of sulphides and other connections of rhenium and platinum is separated from the solution. At that, sodium thiosulfate is added in the form of water solution by its uniform continuous supply to hot acid solution containing platinum and rhenium at the ratio of masses of reagent and soluble rhenium and platinum of 15 to 23.
EFFECT: reducing the flow of sulphur-containing reagent and increasing the extraction degree of platinum from acid solution to the concentrate owing to changing the procedure of introducing the precipitator reagent to acid solution containing platinum and rhenium.
1 tbl, 1 ex
SUBSTANCE: invention is meant for extracting rare-earth metals from phosphogypsum obtained in production of phosphorus fertiliser during sulphuric acid treatment of apatite. The method of extracting rare-earth metals from phosphogypsum involves converting phosphogypsum, dissolving the converted chalk to obtain an insoluble residue containing rare-earth metals. The obtained insoluble residue containing rare-earth metals is dissolved in nitric acid solution at solid-to-liquid ratio of 1:1.5 to obtain a solution and an insoluble residue. The insoluble residue is then washed with water; the obtained solution is mixed with the washing solution; the mixed solution is neutralised to acidity of 0.5-0.25 N with concentrated aqueous ammonia solution and taken for precipitation of rare-earth metal oxalates. The oxalates are precipitated with saturated oxalic acid solution; the residue is washed with 1.5-2.5% oxalic acid solution at solid-to-liquid ratio of 1:2-3. The oxalates are then dried and calcined until rare-earth metal oxides are obtained.
EFFECT: high efficiency of the process of extracting rare-earth metals by cutting duration of the process, the amount of reagents, the size of the equipment, energy resources and avoiding labour-consuming processes.
2 cl, 4 ex
SUBSTANCE: invention relates to methods of separating deactivated rare-earth elements during nitric acid treatment of apatite concentrate from nitrate-phosphate solutions. The method of treating a rare-earth phosphate concentrate isolated from apatite involves decomposition of the rare-earth phosphate concentrate with nitric acid, treating the obtained solution with oxalic acid with precipitation of rare-earth oxalates in two steps, at the first step of precipitation of oxalates of thorium and rare-earth elements, 5-10% oxalic acid in stoichiometric amount is added to rare-earth elements present in the solution, and at the second step of precipitation of rare-earth oxalates, 110-115% oxalic acid in stoichiometric amount is added to rare-earth elements present in the initial solution, and the rare-earth oxalates are then calcined to rare-earth oxides.
EFFECT: invention provides high economic efficiency of the process, which is achieved by avoiding the need to process and bury the precipitate containing thorium.
3 cl, 2 ex
SUBSTANCE: 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.
EFFECT: reduction of energy intensity and improvement of environmental friendliness of the process at its simultaneous simplification.
3 cl, 6 ex