Processing method of black-shale ores

FIELD: metallurgy.

SUBSTANCE: processing method of black-shale ores includes crushing, counterflow two-stage leaching by sulfuric acid solution upon heating, separation of pulps formed after leaching at both stages by filtration. Then valuable soluble materials are washed from deposit at the second stage with strengthened and washing solutions being produced, marketable filtrate is clarified at the first stage for its further processing. Ore is crushed till the size of 0.2 mm, leaching at the first stage is performed by cycling acid solution with vanadium under atmospheric pressure, temperature of 65-95°C during 2-3 hours, till residual content of free sulphuric acid is equal to 5-15 g/l. Leaching at the second stage is performed at sulphuric acid rate of 9-12% from the quantity of initial hard material under pressure of 10-15 atm and temperature of 140-160°C during 2-3 hours. Cake filtered after the first stage is unpulped by part of strengthened solution which content is specified within 35-45% of total quantity.

EFFECT: high-efficiency extraction of rich components, possibility of pulps separation by filtration after leaching with high properties thus reducing costs for separation processes.

3 cl, 1 dwg, 1 tbl

 

The invention relates to the extraction of valuable substances - aluminum, vanadium, uranium, molybdenum and rare earth metals from black shale ores of Kazakhstan. The lower Cambrian carbon-silica rocks, known as black shales, stretching over 2 km from the North to the South of Kazakhstan in the form of two arcs from Ishim Luke to Zailiyskiy Alatau, characterized by an abnormally high content of vanadium, uranium, molybdenum, rare earth elements and have no analogues in the world.

Known combined method of leaching of the ore components, including a two-stage leaching of valuable components, in which the first stage leach is carried out at atmospheric pressure, and the second stage leaching is carried out under high pressure in an autoclave (patent RU №2398901, publ. 10.09.10, IPC SW 3/08, SW 23/00).

The disadvantage of this method is that it is characterized by a low efficiency of extraction of valuable substances from ores, as takes place in conditions of flow motion of the interacting phases.

The closest in technical essence and the achieved effect to the present invention is a method for processing cobalt-rich ferromanganese crust formations, which includes the steps of grinding the feedstock to a particle size 90% - 0.074 mm, two-stage protevtion the e leaching of valuable components (cobalt, Nickel, manganese and copper) with a solution of sulfuric acid at atmospheric pressure, the division formed after leaching effluents at both stages by filtration to obtain commercial filtrate for further processing (patent RU №2261923, opuv. 10.10.05, IPC SW 3/08, SW 4/00).

The disadvantage of this method of processing is that when it is used due to the relatively "soft" conditions of leaching at atmospheric pressure is not achieved high recovery of valuable components and primarily vanadium. The disadvantage lies in the fact that after the leaching of valuable components from the black shale ores are formed at both stages of the pulp filtered with a low performance, which increases the costs of organizing separation processes by filtering.

The technical result of the invention is highly efficient extraction of valuable components - aluminum, vanadium, uranium, molybdenum, rare earth metals from black shale ores, as well as the possibility of separating the sludge by filtration after leaching with high performance, which reduces the cost of separation processes.

The technical result is achieved in the method of processing black shale ore comprising grinding the ore to a particle size of 0.2 mm, two-stage countercurrent videla is ivanie sulfate solution when heated, the division formed after leaching effluents at both stages by filtration, washing the precipitate of the second stage leaching of soluble substances valuable components with getting strengthened and the first leaching solutions, lighting control commodity filter at the first stage of leaching and processing for extraction of valuable components, while leaching in the first stage, carry out the reverse vanadium sulfate solution in the form of fortified solution and part of the leaching solution at atmospheric pressure, a temperature of 85-95°C to a residual content of free sulfuric acid 5-15 g/l for 2-3 hours, and leaching in the second stage is carried out at a flow rate of sulfuric acid 9-12% of the number of the original solid under the pressure of 10-15 ATM, a temperature of 140-160°C for 2-3 hours, filtered after the first stage KEK Rasulova fortified part of the solution, the value of which is set in the range of 35-45% of its total amount.

In addition, when filtered through both stages use supplements flocculants are two types of nonionic and cationic, the pulp after the second stage of leaching before filtering the diluted first proryvnym solution to the ratio of W:T=1.4-1.6:1, and the pulp after the first stage before being filtered thicken with the addition of nonionic and cat the district flocculates to the ratio of W:T=1.4-1.6:1.

It is established that a highly efficient extraction of valuable components from the black shale ores can only be implemented in the conditions of autoclave leaching under pressure. Only the application of pressure to 10-15 ATM, high temperature 140-160°C and the required flow rate of sulfuric acid, 9-12% of the original solid, allow to increase the speed of extraction of vanadium and other valuable components under conditions of countercurrent flow of material flows. However, when using a counter-current method of leaching under high pressure (autoclaves) are very serious difficulties associated with the separation of the liquid and solid phases. In autoclave leaching under conditions of high pressure, temperature, excessive content of sulfuric acid and intensive mixing is a partial dissolution and pereselenie solid phase with the formation of finely dispersed solid particles and a significant increase in the density and viscosity of the liquid phase. In this regard, the separation of such slurries by filtration under vacuum or pressure encountered significant difficulties when choosing hardware design of the filtering processes. Difficulties in choosing the types of filters to separate slurries are forced to give up sometimes from a highly effective method of leaching of trudnowski the ores by high pressure. The present invention allows to minimize and overcome the difficulties. This is achieved by the fact that in the first stage leaching is carried out under atmospheric pressure, under conditions of relatively "soft" impact on solid material and the proposed methods of application of flocculants two types allows to obtain relatively high performance of the filtration process. In the first stage leaching sulphuric acid is mainly spent on interaction with carbonates and kislotosoderjasimi minerals and practically not involved in the extraction process refractory minerals vanadium. And only on the second stage at high values of pressure, temperature, excessive acid content, the necessary residence time of the solid phase in the autoclave, and is the basic process of extraction of valuable components. Efficient leaching of valuable soluble substances from the black shale ores can be achieved with well-defined numerical values of the technological parameters of the process. So the recommended indicators fineness of grinding of raw materials - 0.2 mm are optimal. With increasing size of more than 0.2 mm slows down the kinetics of the leaching process, refractory minerals vanadium. By reducing the fineness of grinding of solid phases is up to 0.1 mm or less is formed up to 90% of finely dispersed hydrated particle class 0.074 mm, which is filtered with a very low performance. Consequently, for the industrial implementation of the processes of filtration would be required apparatus is unreasonably large. The leaching time of the original solid material with an excess amount of sulfuric acid in the first stage leach is also recommended that well defined within 2-3 hours. Time leaching less than two hours is not enough to complete the process of interaction of carbonates and other kislotoprovody minerals with acid. At the time of interaction more than three hours present in the raw materials kislotoproduktsii minerals have time mainly to react with the acid. Leaching in the first stage is carried out at a temperature of 65-95°C, the maximum possible at atmospheric pressure. When the temperature drops below 65°C the efficiency of interaction between the acid and the solid material is reduced. Leaching under pressure is carried out at quite some expense of sulfuric acid per 1 ton of solid material. For black shale ores this value is 9-12% by weight of solid material. With the high consumption of sulfuric acid after the 2nd stage leach, the content of sulfuric acid is between 45 and 75 g/l Remaining after the second stage leaching acid is directed to the first stage leach and spent the ri interaction with the solid source material. After the first stage leaching excess acid is at a level of 5-15 g/l At a flow rate of the acid is less than 9% and the reduction of the excessive acidity of less than 5 g/l, it is evident that the second stage leach was served insufficient amount of the original acid. It is quite certain values to improve the efficiency of extraction of vanadium have featured the pressure of 10-15 ATM and temperature of 140-160°C in partitioned autoclaves designed for a pressure of 20 ATM and a temperature of 200°C. Recommended for repulpable cake obtained after filtration of the slurry on the 1st stage of leaching, use fortified solution in the amount of 35-45% of its total number. This solution is essential to achieve this goal. The recommended percentage of the fortified solution in the amount of 35-45% determines the amount of liquid in the pulp ratio (W:T)supplied to the second stage leach. When the interest rate 35% pulp obtained maximum density, the ratio of W:T which is 0.6:1 (pulp density of 1700 kg/m3). With such a high density pulp and recommended the consumption of sulfuric acid 9-12% of the original solid, the concentration of sulfuric acid in the feed to the autoclave, the slurry obtained maximum and sufficient. If theconcentration acid ensures maximum extraction of valuable components. Despite such a high density, pulp remains flowable and suitable for mixing. As the process of leaching in an autoclave at recommended time 2-3 hours due to dissolution of the solid phase, the pulp becomes more diluted and the ratio of W:T it increases up to 0.8:1. With the increase in the percentage number of fortified solution over 45% pulp density, arriving in the autoclave is reduced. Accordingly decreases the concentration of acid in the liquid phase, which leads to a decrease in the efficiency of extraction of valuable components.

A single inventive concept with the organization of leaching processes in counter-current mode and carrying out the second stage of the leaching process under high pressure and associated technical solutions ways of filtering slurries. As the proposed methods of leaching, and offer solutions in the field of filtration of slurries at both stages allow you to achieve the maximum efficiency of extraction of valuable components and reduce the overall costs of industrial implementation of the method of processing black shale ores. As already noted, the slurry formed after leaching processes black shale ores, are filtered with low. For example, when filtering under vacuum 0.85 kg/cm2in operation Baraba the nogo vacuum filter pulp with a density of 1370 kg/m 3formed after the first stage of leaching, filtration funnel 0.001 m2without the addition of flocculation reagents specific performance of the filtration process was only 1.78 t/m2in day. During the filtration process without the addition of flocculants, a precipitate of a thickness of 3 mm When the thickness of the sediment is not possible to use a drum or disk vacuum filters-machines continuous action that should be applied to continuous processing methods black shale for large-scale production.

To improve the performance of filtering processes slurries formed at both stages of leaching, the proposed use of the additive flocculants are two types of nonionic and cationic. When filtering this slurry under the same conditions with the addition of nonionic flocculant Praestol 2500 with a flow rate of 50 g/t solid and cationic flocculant Praestol 650 with a flow rate of 20 g/t of solid were obtained, the specific capacity of 5 t/m2a day and a sediment thickness of 12 mm, which allows the use of drum vacuum filter for filtering slurries after the 1st stage leach thickening of the pulp after the 1st stage of leaching before being filtered with the addition of these flocculants to the ratio of W:T=1.5:1 (pulp density 1420 kg/m3the unit manufacturer shall detelnosti of the filtering process increases to 5.8 t/m 2in the days when the sediment thickness 14 mm

During the filtration of the pulp obtained after the 2nd stage leach, along with the addition of two types of flocculation reagents nonionic and cationic proposed slurry to dilute the first proryvnym solution to that ratio W:T=1.4-1.6:1, and thickening of the pulp obtained after the 1st stage of leaching. When filtering the slurry with a density of 1670 kg/m3obtained after the second stage of leaching, belt vacuum filter with a three-stage countercurrent washing the cake on the filter surface, 0.001 m2with the addition of two types of flocculation reagents was obtained, the specific capacity of 5 t/m2in day. Upon dilution of the pulp to W:T=1.45:1 (pulp density 1430 kg/m3first proryvnym solution specific performance of the filtration process increases to 6.7 t/m2a day.

The proposed method is as follows. For the practical implementation of the proposed method of processing used unit, shown in the drawing.

The installation includes ball mill I vibration rumble 2, the thickener 3, a container 4 for the preparation of 0.1% solution of the flocculant, the reactor 5 to the atmospheric leaching solid material, a lamellar settling tank 6 for thickening the slurry before filtration, clearly the tee 7 and 8 for the preparation of 0.1% solutions of nonionic and cationic flocculants, the filter 9 for controlling the lightening solutions. The installation also includes drum vacuum filter 10, a receiver 11, a container 12, reactors 13 and 14. In the second stage in the unit consists of autoclave 15, the reactor-mixer 16 and containers for solutions flocculants 17 and 18 and belt vacuum filter 19.

Processing of black shale ores at the facility as follows.

The source of the ore material is crushed to a particle size of 0.2 mm in a ball mill I, operating in closed circuit with a vibrating roar 2, which is fed into the circulating water. From the roar of the pulp is pumped to the thickener 3 with 0.1% solution of flocculant Praestol 2500 from the tank 4. Drain thickener enters into circulation, and the thickened slurry is transported to the first stage leach into the head reactor 5 cascade AIDS. Here comes the part of the filtrate (the fortified solution) from the second stage separation of the pulp, which is carried on a belt vacuum filter 19, and a portion of the leaching solution. In the stage apparatus 5 for 2-3 hours at a temperature of 65-95°C is the interaction of sulfuric acid contained in the filtrate and the washing solution with the original solid material. In the first stage leaching with acid interact carbonates and kislotoproduktsii minerals. Partially soluble solid material Formed after leaching, the pulp goes on thickening in lamellar settling tank 6. To increase the deposition rate of the solid phase of the tanks 7 and 8 in the pulp add 0.1% solutions flocculants are two types of nonionic Praestol 2500 and cationic Praestol 650. From a lamellar settling tank 6 the thickened slurry enters the drum vacuum filter 10 for filtering, and the upper drain is directed by gravity to control lighting in the filter 9 with a fibrous material. The filtrate from filter 10 goes into the receiver 11 and the tank 12, from which is fed to control lighting in the filter 9. The filtered cake is discharged into the reactor 13 and resultatives fortified solution formed by filtering the slurry in the second stage leach. Repulpable oxide in the reactor 13 is part of the fortified solution, which accounts for 35-45% of the total solution. Submission to repulpable such quantities allows to obtain a thick slurry with W:T=0,8:1, which is transported to the second stage leach into the reactor 14 for the preparation of the slurry to leaching in an autoclave 15. In reactor 14 also served the required amount of sulfuric acid. The dense slurry is transported under pressure in the autoclave 15, in which the leaching under pressure of 10-15 ATM, a temperature of 140-160°C for 2-3 hours and excessive content of sulfuric acid 45-75 g/liter autoclave leaching occurs Alu is INIA, vanadium, uranium, molybdenum and rare earth elements and partial dissolution of the solid phase. Then coming out of the autoclave, the slurry is cooled and supplied to the mixer 16, which is served with a certain flow flocculation agent reagents nonionic and cationic types of tanks 17 and 18 and part of the leaching solution. The flow of the leaching solution into circulation allows the diluted dense slurry to the ratio of W:T=1,45:1, which yields the flocculated pulp is filtered with the highest levels. At this ratio, W:T, a sufficient flow rate required flocculants, when mixed with a certain number of revolutions is formed the structure of the pulp, which is filtered with maximum performance. On belt vacuum filter 19 are filtering the original pulp at a temperature of 65°C and the three-step washing the resulting precipitate with a solution of sulfuric acid, resulting from the reverse clarified solutions. The washed precipitate after filtration is sent for further processing, as part of the filtrate is directed to the first stage leach head apparatus 5 cascade leaching. Here comes the first part of the leaching solution.

Example

Is the extraction of valuable soluble substances from the black shale ore Ball is saccadic (Kazakhstan).

The content of aluminium, vanadium, uranium, molybdenum and the amount of rare earths in the original ore is, %: 2,5; 0,5; 0,02; 0,3; and 0.15, respectively.

Sieve characteristics of the ground material to the recommended size of 0.2 mm is presented in table 1.

Table I
Sieve characteristics of the ground material
The original ore
Sieve composition, mmFractional composition
%V2O5, %C, %
+0,315-0,2383,0
-0,315+0,253,740,38612,5
-0,25+0,1611,020,26114,0
-0,16+0,1014,470,33514,5
-0,1+0,0749,89 0,35114,2
-0,074+0,07160,880,57518,0

A method of processing black shale ores is carried out in accordance with the proposed technical solution for the installation, ensure the performance of the original ore 48 tons per day. The original ore is crushed in a mill I, is classified to rumble 2 to a predetermined sieve characteristics (table) and with a density of 1200 kg/m3(F:T=2,6:1) is supplied to the operation of the thickening with the addition of flocculant Praestol 2500. The thickened slurry with a density of 1490 kg/m3(F:T=0.9:1) is pumped to the first stage leach process in the head of the reactor 5 cascade AIDS. Here come the filtrate in the amount of 1.23 m3/h obtained after filtration of the slurry from the second stage leach, and part of the leaching solution in the amount of 0.75 m3/h In the reactor 5 at a temperature of 90°C is the processing of raw ore with a solution of the acid contained in the filtrate and the washing solution (the first stage leaching) for 2.5 hours. As a result of the leaching process produces pulp with a density 1376 kg/m3(F:T=2:1), in the amount of 3.5 m3/H. With leaching on the 1st stage, the solid part in the amount of 3% of the original solid is dissolved. Bullets is and then from the tail reactor 5 comes with the addition of flocculants Praestol 2500 and Praestol 650 condensed in a lamellar settling tank 6, in which condenses to density W:T-1.5:1, and is supplied to the filtering drum vacuum filter 10 with surface filtration 10 m2. The filtrate from the filter through a hydraulic seal with the upper drain plate clarifier is fed to control lighting in the filter 9. As a result of processing 48 tons/day (2 t/h of raw material formed of 3 m3/h commodity solution with content (g/l): 3.5 vanadium 0.15 uranium, 0.25 molybdenum, 0.3 amount of rare earths. When filtering the flocculated thickened slurry under vacuum in the first stage with the costs of flocculants Praestol 2500 - 50 g/t and Praestol 650 - 20 g/t achieved specific performance 5.8 t/m2day. This gives the cake a thickness of 14 mm and 20%humidity. The cake in the reactor 13 resultatives fortified solution in the amount of 0.88 m3/h coming from the second stage of filtration. The amount of washing solution is supplied to repulpable is 35% of the total number of fortified solution. By filing such a large number of fortified mortar density of the pulp in the reactor 13 coming in the second stage of leaching into the reactor 14 and autoclave 15, is 1600 kg/m3(F:T=0,8:1). In reactor 14 is served, the initial acid number 0,23 t/h (11.4% of the original solid). In the autoclave is carried out leaching at a pressure of 13 ATM, pace is the atur 150°C for 2.5 hours. The residual content of acid after stage 2 leach -75 g/l In autoclave leaching is the dissolution of the solid phase in the amount of 4.2 tonnes leachate is formed pulp density 1672 kg/m3(F:T=1,14:1), the vanadium content in the liquid phase of the pulp is 6.5 g/l After leaching, the slurry is diluted proryvnym solution and with a flow rate of 2.2 m3/h is fed to the filtration and washing of soluble substances from the sludge on the belt vacuum filter surface of the filter 12 m2. On the filter, organized a three-stage countercurrent washing of soluble substances from the sediment at specific discharge of wash water 1 m3/t solid. To improve the performance of the filtering process is part of the leaching solution in the amount of 0.45 m3/h is fed into circulation in the reactor-mixer 16 for mixing with the original slurry entering the filter. Same here with the consumption of 200 g/t of solid serves flocculant Praestol 2500 and flocculant Praestol 650 with a flow rate of 150 g/t solid. In the reactor 16 is formed flocculated slurry ratio G:T=1,42:1, which is filtered with a high performance 6.7 t/m2day. During the filtration and washing of the formed cake thickness of 13 mm and a humidity of 25%. The vanadium content of moisture in the washed sediment - 0.05 g/L. the Effectiveness of washing vanadium and D. the natives valuable soluble substances 99,6%. In the filtering process formed the filtrate in the amount of 1.39 m3/h and a wash solution of volume 1.66 m3/H. As noted above, part of the fortified solution is supplied to repulpable oxide in the reactor 13, and the other part is fed to the first stage leach. Submission fortified solution in the amount of 0.88 m3/h (35% of the number of fortified solution) and allows you to get the 2nd stage leach pulp, high density W:T=0,8:1, with the aim of obtaining the maximum concentration of acid in the autoclave and the maximum recovery of valuable components.

The consumption of sulfuric acid in the process is carried out on the basis of control over excess (residual) content of sulfuric acid in the clarified solution (or filtrate)obtained in the first stage of filtration. The check digit is the acid content of 5-15 g/l At lower acid concentration of less than 5 g/l or no increase acid consumption on the 2nd stage. With the increase of excess acid concentration of more than 15 g/l, respectively, reduce the consumption of acid on the 2nd stage.

The utilization of the acid in the processing of raw materials in excess of the concentration of sulfuric acid on the 1st stage 15 g/l is 81,1%.

From the results of this work can be seen that the use proposed is the R technical solutions managed from refractory ore deposits of Malasauskas to achieve high extraction (%): aluminum - 75,0; vanadium - 91,0; uranium - 98,0; molybdenum - 85,0; and the amount of rare earths - 75,0.

As a result of applying the aggregate of distinctive features was able to achieve a high recovery of valuable components and to provide separation formed by the leaching of sludge by filtration with high performance, which will be used in the construction of large enterprise performance.

1. A method of processing black shale ore comprising grinding the ore to a particle size of 0.2 mm, two-stage countercurrent leaching sulfuric acid solution under heating, the division formed after leaching effluents at both stages by filtration, washing the precipitate of the second stage leaching of soluble substances valuable components with getting strengthened and the first leaching solutions, lighting control commodity filtrate in the first stage of leaching and processing for extraction of valuable components, while leaching in the first stage, carry out the reverse vanadium sulfate solution in the form of fortified solution and part of the first leaching solution at atmospheric pressure, a temperature of 85-95°C to a residual content of free sulfuric acid 5-15 g/l for 2-3 h, and leaching in the second stage is carried out at a flow rate of sulfuric acid 9-12% of the original solid under the pressure of 10-15 ATM., the temperature of 140-160°C for 2-3 h, while the filtered after the first stage KEK Rasulova fortified part of the solution, the value of which is set in the range of 35-45% of its total amount.

2. The method according to claim 1, characterized in that during the filtration of slurries at both stages use supplements flocculants are two types of nonionic and cationic.

3. The method according to claim 1, characterized in that the pulp after the first stage of leaching before filtering thicken with the addition of nonionic and cationic flocculants to the ratio of W:T=1,4-1,6:1.

4. The method according to claim 1, characterized in that the pulp after the second stage of leaching before filtering the diluted first proryvnym solution to the ratio of W:T=1.4 to a 1.6:1.



 

Same patents:

FIELD: metallurgy.

SUBSTANCE: processing method of black-shale ores with rare metals extracting includes leaching of ore by sulphuric acid solution with dilution of rare metals. Leaching is performed in autoclave by sulphuric acid solution consisting of free and combined sulphuric acid with ratio of H2SO4(free):H2SO4(comb)=2:1, and containing 25-45 g/l of iron sulphate, 70-90 g/l of aluminium sulphate and 0.5 g/l of nitric acid. At that the process is performed under pressure in autoclave equal to 10-15 atm with mixing at temperature of 140-160°C in concentration range of general H2SO4(gen) equal to 350-450 g/l under pulp density S: L=1:0.7-0.9, preferably 1:0.8, under constant oxidation-reduction potential Eh in the system equal to 350-450 mV during 2-3 hours till residual concentration of free H2SO4(free) is within 45-75 g/l.

EFFECT: increasing break-down of ore and extraction of rare metals: vanadium, uranium, molybdenum and rare-earth elements, reducing consumption of acid and improving efficiency of autoclave volume usage.

1 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to the technology of processing chemical concentrates of natural uranium, involving leaching (dissolving) the concentrate and extracting uranium using tributyl phosphate in a hydrocarbon diluent. The method involves dissolving the concentrate using aqueous nitric acid solution, feeding the obtained aqueous uranyl nitrate solution to the extract outputting step of a stepped extraction unit and extracting uranium with tributyl phosphate in a hydrocarbon diluent. Extraction is carried out by counterflow interaction of the aqueous and organic phases. Concentrate containing thorium impurities in ratio of 1 wt % to uranium is used. During extraction at the extract outputting step, the step for saturating the extractant with uranium is kept at least 87% of the maximum saturation of the extractant with uranium, and a portion of the aqueous phase, which is not more than 60 vol. % of the uranyl nitrate solution fed to the extract outputting step, after one of the extraction steps is removed from the extraction process and fed for dissolving the uranium concentrate.

EFFECT: high extraction of uranium and nitric acid from the raffinate.

1 tbl

FIELD: metallurgy.

SUBSTANCE: method involves use of an unbalanced solution consisting of a solution from the washing process of anionite from the acid and filtrate from the filter press, and their removal from the process together with a mother solution from deposition of natural uranium concentrate through an additional saturation operation together with a marketable reclaimed product. For that purpose, the plant includes a local solution recirculation circuit in the form of a collector for solutions of unbalanced and mother concentrate from deposition, which is connected to pipelines of the above solutions and equipped with solution supply pipelines attaching the collector through a gravity tank to an additional saturation column from the marketable reclaimed product and to a solution return pipeline attaching the gravity tank to the solution collector of the local solution recirculation circuit.

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2 cl, 2 dwg, 1 tbl, 2 ex

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4 tbl, 4 ex

FIELD: chemistry.

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EFFECT: wider range of methods of extracting americium.

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EFFECT: increasing extraction degree of vanadium, uranium, molybdenum; improving the complexity of ore use owing to associated extraction of rare-earth elements.

18 cl, 1 dwg

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EFFECT: decrease of sulphuric acid content in desorbing solution and rich eluate and reduction of sulphuric acid consumption, decrease of desorbing solution flow and anion exchange resin ratio at de-sorption, increase of uranium content in rich eluate at decrease of rich eluate volume and decrease of uranium residual content by 1-2 levels in anion exchange resin after de-sorption.

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FIELD: chemistry.

SUBSTANCE: invention relates to chemical engineering of inorganic substances and can be used to produce uranium tetrafluoride. The method of producing uranium tetrafluoride involves reduction and fluorination of triuranium octoxide with vapour from decomposition of ammonium fluoride taken in excess of 100-130 mol. % of the stoichiometric amount at temperature in the range of 260-700°C.

EFFECT: invention provides a simple industrial method of producing uranium tetrafluoride and reduces the cost of the product.

3 ex

FIELD: metallurgy.

SUBSTANCE: procedure for processing uranium hexafluoride involves supply of the main stream of gaseous uranium hexafluoride into uranium-fluorine plasma generator, supply of an additional flow of gaseous uranium hexafluoride into an additional circuit to the uranium-fluorine plasma generator, forming of a cluster of uranium-fluorine plasma out of the primary and secondary streams of uranium hexafluoride at the entrance to the uranium-fluorine plasma generator. Then uranium-fluorine plasma flow is formed in the separation chamber of the magnetic separator, removal of the neutral atomic fluorine from the uranium-fluorine plasma flow, condensation of uranium, collecting of molten metallic uranium, formation of a bar of metallic uranium and output of the formed uranium bar. The precession of a cluster of uranium-fluorine plasma is performed along a conical surface in the skin layer by means of magnetic and/or gas-dynamic scanning of additional flow of uranium hexafluoride. A device for implementation of the said procedure is also suggested.

EFFECT: increased stability of the radio frequency discharge by improving the communication of radio frequency generator with the load - the flow of uranium-fluorine plasma of uranium hexafluoride.

7 cl, 3 dwg

FIELD: metallurgy.

SUBSTANCE: processing method of black-shale ores with rare metals extracting includes leaching of ore by sulphuric acid solution with dilution of rare metals. Leaching is performed in autoclave by sulphuric acid solution consisting of free and combined sulphuric acid with ratio of H2SO4(free):H2SO4(comb)=2:1, and containing 25-45 g/l of iron sulphate, 70-90 g/l of aluminium sulphate and 0.5 g/l of nitric acid. At that the process is performed under pressure in autoclave equal to 10-15 atm with mixing at temperature of 140-160°C in concentration range of general H2SO4(gen) equal to 350-450 g/l under pulp density S: L=1:0.7-0.9, preferably 1:0.8, under constant oxidation-reduction potential Eh in the system equal to 350-450 mV during 2-3 hours till residual concentration of free H2SO4(free) is within 45-75 g/l.

EFFECT: increasing break-down of ore and extraction of rare metals: vanadium, uranium, molybdenum and rare-earth elements, reducing consumption of acid and improving efficiency of autoclave volume usage.

1 tbl, 1 ex

FIELD: metallurgy.

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

FIELD: chemistry.

SUBSTANCE: method includes leaching of rare-earth metals (REM) from phosphogypsum with 1-5% solution of sulphuric acid, REM sorption from leaching solution with cationite, REM desorption, precipitation of REM concentrate from desorbate, obtaining REM concentrate and mother liquor, which is used for REM desorption. Cationite after desorption is returned at sorption stage. Phosphor and fluorine are precipitated from mother liquor, phosphor -and fluorine-containing sediment are filtered and filtrate is used as return water in leaching. REM leaching and sorption are carried out simultaneously. Obtained pulp is filtered through mesh filter with separation of saturated REM cationite. After that, pulp is filtered with obtaining non-dissoluble residue and mother liquor of sorption. Before desorption cationite is treated with part of desorbate.

EFFECT: simplification of technology, reduction of duration of REM leaching and sorption, increased efficiency of sorption and desorption and concentrate quality.

12 cl, 1 dwg, 3 ex

FIELD: metallurgy.

SUBSTANCE: method includes dissolution of a sample of analysed alloy and separation of cerium from the base of the alloy and macrocomponents. At the same time the base and macrocomponents are separated from cerium by serial deposition and extraction of the alloy base and macrocomponents of the alloy from the solution. Deposition is carried out with sodium diethyldithiocarbamate, extraction - with dithizone in chloroform. After separation of the organic phase, the cerium content is detected in water phase with the spectrometric method.

EFFECT: elimination of harmful influence of high contents of iron and other components of steel and alloy base, improved quantitative analysis, higher accuracy and reproducibility of the analysis method.

1 tbl, 1 ex

FIELD: chemistry.

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

FIELD: metallurgy.

SUBSTANCE: solid extractant is proposed (SEX) for extraction of scandium from scandium-containing solutions, containing a styrene divinyl benzene matrix with di-(2-ethyl hexyl)phosphoric acid. At the same time it additionally contains dibenzo-18-crown-6 at the following ratio of components, wt %: di-(2-ethyl hexyl)phosphoric acid 28-30, dibenzo-18-crown-6 28-30, styrene divinyl benzene - balance, besides, the ratio of styrene and divinyl benzene in the matrix is equal to 65÷70:30÷35. There is a method also suggested for production of the above extractant.

EFFECT: quite high selectivity by scandium and efficient separation of scandium and yttrium with their joint existence in a solution.

2 cl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to hydrometallurgical processing of mineral material, particularly scandium-containing "tailings" obtained during beneficiation of titanium-magnetite ore by wet magnetic separation. The method of extracting scandium is three-step sulphuric acid leaching of scandium, wherein at the first step, leaching is carried out with recycled solution after extraction of scandium at temperature of 30-50°C and solid to liquid ratio of 1:6-7 for 3-4 hours; the pulp is then divided into a solid phase and a liquid phase; at the second step, a portion of the solution obtained from the first step is returned to the solid phase and sulphuric acid is added to concentration of 340-360 g/l and sodium fluoride is added in amount of 20-25 kg fluorine/t solid; leaching is carried out at temperature of 95-98°C and solid to liquid ratio of 1:2.5-3 for 3-4 hours; further, at the third step, the pulp is diluted in solid to liquid ratio of 1:6.5-7.5; treatment is carried out at temperature of 95-98°C for 3-4 hours.

EFFECT: invention increases extraction of scandium, cuts the overall duration of the leaching process and consumption of sulphuric acid and sodium fluoride.

3 ex, 1 tbl

FIELD: metallurgy.

SUBSTANCE: proposed method comprises sulfuric acid leaching of scandium from red mud, pulp filtration, scandium sorption from sulfuric acid solutions, desorption from organic phase by carbonate solution to obtain column effluent. Then, scandium poorly soluble compounds are precipitated from column effluent, precipitate is filtered out, flushed, dried and annealed to get scandium-bearing concentrate. Note here that said leaching is performed by 10.0-13.5%-sulfuric acid at pulp initial vibration cavitation at rotary velocity of 35-60 m/s for 15-35 min. Scandium is precipitated from column effluent by potassium caprinate in amount of 75-100 g/t of scandium at pH 3.5-4.5 and exposure for 15-25 min.

EFFECT: increased yield.

3 cl, 2 tbl, 2 ex

FIELD: metallurgy.

SUBSTANCE: proposed method comprises extraction of rare-earth metal cations by organic phase including extragent solution in inert diluter. Naphthenic acid is used as said extragent. Kerosene is used as inert diluter. Extraction is conducted in three stages at relationship between organic and aqueous phases O:A=1·(9-11) at every stage. Note here that, at first stage, europium cations (III) are extracted at content of naphthenic acid in kerosene of 10-13 vol. % and aqueous solution pH 5.0-5.1. At second stage, samarium cations (III) are extracted at content of naphthenic acid in kerosene of 13-16 vol. % and aqueous solution pH 4.6-4.7. At third stage cerium and lanthanum cations (III) are extracted at the same content of extragent and pH 5.0-5.1.

EFFECT: higher yield.

4 dwg, 1 ex

FIELD: metallurgy.

SUBSTANCE: method of extracting rare-earth metals from solutions containing iron (III) and aluminium comprises sorption of rare-earth metals on sorbent. Ampholyte with iminodiacetic functional groups is used as said sorbent. Sorption is carried out after preliminary neutralisation or acidification of solution to pH 4-5 by whatever alkaline or acid agent to add ampholyte in obtained pulp with separation of solid fraction. Sorption is conducted at ampholyte:pulp ratio of 1:50-1:150, phase contact time of 3-6 h and in the presence of reducing agent.

EFFECT: higher selectivity.

5 tbl, 5 ex

FIELD: metallurgy.

SUBSTANCE: processing method of black-shale ores with rare metals extracting includes leaching of ore by sulphuric acid solution with dilution of rare metals. Leaching is performed in autoclave by sulphuric acid solution consisting of free and combined sulphuric acid with ratio of H2SO4(free):H2SO4(comb)=2:1, and containing 25-45 g/l of iron sulphate, 70-90 g/l of aluminium sulphate and 0.5 g/l of nitric acid. At that the process is performed under pressure in autoclave equal to 10-15 atm with mixing at temperature of 140-160°C in concentration range of general H2SO4(gen) equal to 350-450 g/l under pulp density S: L=1:0.7-0.9, preferably 1:0.8, under constant oxidation-reduction potential Eh in the system equal to 350-450 mV during 2-3 hours till residual concentration of free H2SO4(free) is within 45-75 g/l.

EFFECT: increasing break-down of ore and extraction of rare metals: vanadium, uranium, molybdenum and rare-earth elements, reducing consumption of acid and improving efficiency of autoclave volume usage.

1 tbl, 1 ex

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