Complex processing method of carbon-silicic black-shale ores

FIELD: metallurgy.

SUBSTANCE: invention refers to complex processing method of carbon-silicic black-shale ores, which contain vanadium, uranium, molybdenum and rare-earth elements. The above method involves ore crushing to the particle size of not more than 0.2 mm and two leaching stages. Oxidation sulphuric-acid leaching is performed at atmospheric pressure. Autoclave oxidation sulphuric-acid leaching is performed at the temperature of 130-150°C in presence of oxygen-containing gas and addition of a substance forming nitrogen oxide, as a catalyst of oxygen oxidation. Ion-exchange sorption of uranium, molybdenum, vanadium and rare-earth elements is performed from the obtained product solution.

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

 

The invention relates to the field of hydrometallurgy and can be used for complex processing of carbon-silica ores.

It is known that the hard carbon-siliceous black shale ore, in particular, the ore deposits of Malasauskas (North-Western Karatau), contain vanadium, and uranium, molybdenum and rare earth elements (REE).

The main part of vanadium (55%) mentioned the ore is contained in the form of sulfides (petronic V5S5; Vx2+Sy), 35% in the form of CR # (V2+O·V23+O3); montroseite (V, Fe)O·OH), and the remaining 10% are presented sredneetazhnye micas MeV3+[V4+·Si3O10]·[OH]2; Famicom BAV display3+2(Si·V4+)4O10·4H2O; bronzes (MeV4+-V5+O4); kazachstanicum (Fe3V4+·V5+12O23·8,55H2O) and soluble minerals - vanadates MeV5+O4and hewettite CaV6O16·9H2O. Thus, the main form of vanadium mineralization in black shales is patronic.

Sulfides and Spinelli are refractory (resistant) and their oxidation and dissolution occurs only in relatively harsh conditions, at elevated temperature (>100°C) and concentrations of solvent. This fact largely determines not the residual degree of extraction of vanadium (52-82%) in sulfuric acid leaching of black shale ores.

There is a method of processing vanadium-containing raw materials, including carbon quartzite Karatau (EN 2374344 C2, NGO vanadium catalyst"; "Firm "Balausa", 27.11.2009). This technology involves a two-stage heap (percolation) leaching of vanadium from ores hole size (0.01 to 0.6 m) by laying it in a heap with simultaneous mixing with concentrated sulfuric acid with a flow rate of at least 30 kg/t and leaching of vanadium in the first stage, working parent sorption density of irrigation 3.5-4.5 l/m2and the number of cycles of at least three, doreplace the reverse of the manifold sorption sulfuric acid to its content of 8.0-8.5% and feed them to the pile in the second stage leach. The sorption of vanadium is carried out at a pH of not more than 1.3 and 1.5.

The disadvantages of this method are the low extraction of vanadium from ores downhole particle size of about 75%, and the absence of associated extraction of other valuable metals (uranium, molybdenum, REE).

There is also known a method for integrated processing of carbon vanadium-uranium ore Karatau (V.A. Kozlov and other Complex processing quartzite Karatau. VIII all-Russian conference 26-29 September 2000, houseboy. Vanadium, chemistry, technology, applications. Abstracts, p.146). The method comprises grinding the ore to a particle size of 50-70 mm, heap leaching concrete is sulfuric acid, subsequent conditioning solutions and sorption of vanadium and uranium anion exchanger AMP. Their subsequent desorption is carried out separately - uranium solution of ammonium nitrate and sulfuric acid at a pH of 1-1,5, and vanadium solution of ammonium nitrate and ammonia at a pH of 8.2 is 8.7. Uranium and vanadium decorate can be recycled to the commodity nitrous-oxide of uranium and vanadium pentoxide by known methods. Quartzite after heap leaching can be utilized as a flux in obtaining high-carbon ferrochrome and yellow phosphorus.

The disadvantage of this method is the unattainability of a sufficiently high extraction of vanadium, uranium and other valuable components of the pieces of ore so large (50-70 mm) (≥70%)in which the diffusion of oxidant and solvent to a significant portion of the target mineralization is almost impossible for any affordable length of the process. In addition, there is accompanying extraction of scarce and expensive metals such as molybdenum and rare earth elements (lanthanides + yttrium).

The method for extracting uranium, molybdenum and vanadium from silicate ores (EN 2211253 C2, sue VNIIHT", 27.08.2003), in which the oxidant is used, the anion exchange resin in OH-form when creating the oxidation-reduction potential (ORP) -50 to +150 mV. Such redox potential does not allow Vyselki is the substance of the uranium, molybdenum, vanadium and REE from shale ores, for which it is necessary to maintain the value of the redox potential for leaching within 400-470 mV. In addition, in this method, the sorption of metals from the ore pulp, not from solutions leads to increased specific consumption of the anion due to its abrasion (grinding).

The known method for integrated processing of uranium-vanadium ore deposits Ore (Central desert), containing ~0.1 and 1.0% of the uranium and vanadium, respectively (Smirnov I.P., and other Modern trends in the development of the technology integrated use of uranium-vanadium and non-traditional (man-made) vanadium raw materials. Strategy use and development of mineral resources of rare metals of Russia in XXI century. Volume 2. Reports of the International Symposium, 5-9 October 1998, M.: "minerals", No. 7, VIMS, 2000, s-175). Rocks are represented carbonaceous shales. The main part of vanadium (~80%) is in the form of a relatively hard mineralization - roscoelite and detonite, while the smaller part is in the form of lewkowskiej of organovanadium - carnotite and tyuyamunite. Vanadium minerals are predominantly micron particle size and dispersed in the ore body. It is suggested to sulfuric acid oxidizing leaching of vanadium and uranium from ore at 130-150°C and the residual acidity of the pulp 15-20 sec with the addition of potassium compounds for the deposition of trivalent iron in the form of potassium jarosite to a residual concentration of iron 1-3 g/l, and then spend the sorption of uranium and vanadium from the pulp of obtaining their merchandise oxides. This method allows to achieve maximum extraction of uranium and vanadium in commodity products, respectively, 97%and 80%.

The disadvantages of this method include the additional use of potassium compounds is not high enough the extraction of vanadium from ores.

Closest to the proposed invention to the technical essence and the achieved result is a method for processing refractory carbon-siliceous black shale ores described in Ambatovy ACTING "Development of technology of production of metavanadate ammonium from black shale deposits of Malasauskas". The dissertation on competition of a scientific degree of candidate of technical Sciences, Republic of Kazakhstan, Almaty, 2010 - prototype.

According to the method prototype black shale ore (containing ~1,1% V2O5and humidity ~10%) crush (crush) particle size up to 25 mm, then the crushed ore is treated for 2 h with sulfuric acid (flow rate of 140 kg/t) in order to saturate its pores and cracks of the lumps of ore, the temperature rises to 45°C. Then, this ore is subjected to heat treatment preferably at 140°C and atmospheric pressure for 4 h (in particular in a rotary kiln), the so-called sulfatization, with the aim of opening (oxidative destruction) is of levidow and CR#, containing vanadium in the lower (V2+; V3+) oxidation States and its transfer in acid-soluble form of sulphate vanadyl VOSO4when the redox potential is not higher than 450 mV, with no oxidation of the vanadium to the pentavalent state.

The thus prepared black shale ore is formed in the ore pile and subjected to heap leaching in two stages: the first stage of water at T:W=1:2 with obtaining productive solution having a pH of 1.4 and concentration 2,39 g/l V2O5when the degree of extraction of vanadium from ores 43,8% and in the second stage leach solution with a concentration of 30 g/l H2SO4if T:W=1:0.5 to obtaining a productive solution (pH 0,8)containing 1,93 g/l V2O5. In the two-stage leach, the average concentration of components in a productive solution is, g/l: 2,10 V2O4; 0,06 U; 0,06 Mo; 0,01 Σ; 60 Fe; 63,4 Al; 91,5 P.

The extraction of vanadium, uranium and molybdenum from the pregnant solution is carried out by anion-exchange sorption. First by collective anion-exchange sorption of uranium and molybdenum at a pH of 1.3-1.5, in particular, with the use of anion exchange resin Ambersep 920. Then spend the conditioning of mother solutions in the pH value with NaHCO3(flow rate of 8 kg/m3) and ORP using hydrogen peroxide (flow rate 60%H2 2equal to 1 l/m3for oxidation of vanadium in the pentavalent state. Then from the mother liquor absorb vanadium anion exchange resin Ambersep 920 with its saturation up to 300-350 kg/t V2O5. The mother liquor sorption sent for heap leaching, and the anion on Considine its vanadium up to 400-450 kg/t V2O5using synthetic solution with a concentration of decavanadate acid (H6V10O28equal to ~15 g/l and at a pH of 2.5-3.5. This allows taking into account the subsequent leaching sulfuric acid solution saturated vanadium anion exchange resin at T:W=1:3 to achieve a high (98%) purity of the anion and vanadium product from impurities, including phosphorus.

Desorption of vanadium spend solution mixtures of ammonium nitrate (150-200 g/l) and ammonia at a pH of 8.5 and a temperature of 30-35°C with separation in the solid phase metavanadate ammonium NH4VO3formed within 15 hours. After filtering receive metavanadate as a ready-vanadium product and the filtrate, which is used in the turnover for the preparation of Stripping solution. The anion exchange resin after Stripping of vanadium recharges in SO42-form using a sulfuric acid solution and recycle on stage sorption of vanadium.

The main disadvantages of the prototype method are low vanadium recovery from the carbon-silica Chernokozovo the ore, equal to about 52%, the expenditure of significant amounts of sodium bicarbonate (8 kg/m3productive solution), and the absence of associated extraction of scarce and expensive REE.

Patent-pending method for integrated processing of carbon-siliceous black shale ores containing vanadium, uranium, molybdenum, rare earth elements, includes the following operations:

the ore grinding to particle sizes not exceeding 0.2 mm;

campaign oxidative acid leaching of the ore tetravalent vanadium, uranium, molybdenum, rare earth elements at atmospheric pressure obtaining sulphate pulp;

air conditioning sulfate pulp to a pH of 1.8 to 2.2;

dividing the pulp into a productive solution containing tetravalent vanadium, uranium, molybdenum, rare earth elements, and a solid phase;

autoclave oxidative acid leaching of the solid phase of vanadium, uranium, molybdenum, rare earth elements at the final concentration of sulfuric acid 35-45 g/l, a temperature of 130-150°C, in the presence of oxygen-containing gas and the substance that forms nitric oxide as catalyst for the oxygen oxidation with getting leached pulp and waste gases containing nitrogen oxides;

the separation of the leached pulp liquor containing vanadium, uranium, mo is ebden, rare earth elements, which are served at the above-mentioned agitation leaching of ore at atmospheric pressure, and the insoluble residue, which is washed and sent for recycling;

the feed autoclave leaching products purification of exhaust gases containing nitrogen oxides, and water from washing the insoluble residue;

anion-exchange sorption of uranium together with molybdenum with getting the mother liquor and the anion exchange resin saturated with uranium and molybdenum, their desorption and obtaining uranium and molybdenum products in a known manner;

the oxidation of tetravalent vanadium to its pentavalent state in the mother solution, sorption of uranium and molybdenum and anion-exchange sorption of vanadium with obtaining stock solution and saturated vanadium anion exchange resin, the desorption of vanadium from the anion exchange resin and obtaining vanadium product in a known manner;

cation exchange sorption of rare earth elements from the mother liquor sorption of vanadium with getting the mother liquor and the cation exchanger, which is rich in rare earth elements, desorption from the cation and extraction of rare-earth products in a known manner, the utilization of the resulting stock solution in a known manner.

The method can be characterized by the fact that the operation of the agitation leaching at atmospheric pressure is avodat at a pH of 1.2-1.6, redox potential (ORP) 400-450 mV, the temperature of 60-70°C, the ratio of solid: liquid = 1:(1-2), duration 2-4 hours and the use of ferric ions as an oxidant.

The method can be characterized and the fact that the said agitation leaching is carried out at a pH of 1.3-1.5, ORP=400-430 mV, the temperature of 60-70°C, the ratio of solid: liquid = 1:1.5, duration 3 h, and the use of ferric ions as an oxidant.

The method may also be characterized as those mentioned autoclave leaching is carried out at ORP=430-470 mV, the ratio of solid: liquid = 1:(1.0 to 2.0), and duration of 2-3 hours, and the fact that the mentioned autoclave leaching is carried out at a temperature of 140°C, ORP=450-460 mV, the ratio of solid: liquid = 1:(1.0 to 2.0), and duration of 2-3 hours

The method can be characterized, moreover, by the fact that as a substance that forms nitric oxide, use acid blend (89% HNO3) or nitric acid or sodium nitrite.

The method can be characterized by the fact that the separation of the air-conditioned pulp to a productive solution and the solid phase is produced by filtering, and the fact that the separation of the air-conditioned pulp to a productive solution and the solid phase is carried out by condensation with obtaining clarified productive solution is thickened suspension, which is filtered to obtain productive solution and solid phase in the form of a cake.

The method can be characterized also by the fact that the separation of the leached pulp liquor and insoluble residue produced by countercurrent decantation and then filtering the thickened suspension, as well as the fact that the washing of the insoluble residue is produced on the filter mother liquor sorption of rare earth elements, and optionally water.

The method may be characterized, in addition, the fact that the anion-exchange sorption of uranium together with molybdenum conduct of productive solution at a pH of 1.8 to 2.2, ORP=400-430 mV and a temperature not exceeding 60°C, and that the oxidation of tetravalent vanadium to its pentavalent state in the mother solution to produce hydrogen peroxide.

The method can be characterized and the fact that the anion-exchange sorption of vanadium from the oxidized mother liquor is carried out at a pH of 1.8 to 2.2, ORP=750-800 mW and a temperature not exceeding 60°C, and the fact that cation exchange sorption of rare earth elements from the mother liquor vanadium sorption is carried out at a pH of 1.8 to 2.2, the AFP is not above 350 mV and a temperature not exceeding 60°C.

The method can be characterized by the fact that anion-exchange sorption of uranium together with molybdenum spend on anion exchangers AMP or Ambersep 920, as well as the fact that the anion-exchange sorption of vanadium spend on anyone the e Ambersep 920, moreover, the fact that cation exchange sorption of rare earth elements is performed on cationite KU-2-8h or Ambersep n.

The technical result of the invention is to increase the degree of extraction of vanadium up to 95%, uranium, molybdenum, up to 90%, increasing the complexity of application of ore due to the associated ~80%of REE extraction. Additional technical result - the greening process by purification of exhaust gases from nitrogen oxides with obtaining nitrogen compounds used in autoclave leaching.

Thus, the distinctive features of the process are: grinding the carbon-siliceous black shale ore to a particle size of the particles not exceeding 0.2 mm; two-stage leaching of vanadium, uranium, molybdenum and rare earth elements, in which the first stage holding campaign oxidative acid leaching at atmospheric pressure, pH of 1.2-1.6, ORP=400-450 mV when using ferric ions as an oxidant; air conditioning resulting slurry to a pH of 1.8 to 2.2, is favorable for the sorption of U, Mo, V, and REE, and the separation of the pulp to a productive solution and a solid phase; autoclave oxidative acid leaching vanadium, uranium, molybdenum, REE from the solid phase at a temperature of 130-150°C and a final concentration of sulfuric acid 35-45 g/l and ORP=430-470 mV in the presence of oxygen and the use of nitric oxide as catalyst for the oxygen oxidation; feed liquor obtained in autoclave leaching to the first stage leach; technological parameters of sorption of uranium, molybdenum, vanadium, REE; additional cation exchange sorption of REE from the mother liquor sorption of vanadium.

The invention is illustrated in the figure is a schematic diagram of the processing of carbon - siliceous black shale ores.

An example of a preferred implementation of the invention.

Carbon-siliceous black shale ore containing, in wt.%; 0,52 V; ~0,02 U; 0,03 Mo and ~0,06 Σ, represented mainly by dysprosium (0,010-0,020%), gadolinium (0,025%), samarium (0,020%); and 0,012% yttrium and about 10% carbon, crushed up by 0.2 mm In the form of a slurry at T:W=1:0,8 crushed ore is fed to the first stage oxidizing sulfuric acid leaching of vanadium, uranium, molybdenum, REE when mixed with sulfuric acid liquor of the second stage of leaching at atmospheric pressure, T:W=1:1,5; a temperature of 60-70°C, pH of 1.3-1.5; ORP=400-430 mV for 2 h in the presence of ferric ions (and possibly ions, pentavalent vanadium) as oxidant.

The resulting slurry is conditioned to pH 1.8-to 2.2-crushed original ore (or other alkaline neutralizer character) and divide it by filtering the productive solution containing Vana is s (4+) in the form of VOSO 4, uranium, molybdenum, REE and a solid phase in the form of a cake. KEK is directed to the second stage leach - autoclave oxidative acid leaching at a temperature of 140°C, T:W=1:(1.0 to 2.0), the final concentration of sulfuric acid 40 g/l, with a duration of 2 h in the presence of oxygen-containing gas (technical oxygen or compressed air) as the oxidant, with the addition in the leach slurry nitrogen-containing substances, in particular, acid blend (89% HNO3) or nitric acid or sodium nitrite (or other substances)that form in the leaching of nitrogen oxide as catalyst for the oxygen oxidation while maintaining the redox potential of the aqueous phase of the pulp, equal 430-450 mV.

The total consumption of sulfuric acid in the first and second stages of leaching is ~140 kg/t ore. In the second stage of leaching is also served with wash water generated during the washing of the insoluble residue autoclave leaching and nitrogen-containing substances generated during the cleaning of waste gases from nitrogen oxides.

The presence of oxygen in the gas-vapor phase of the autoclave causes the oxidation formed during leaching practically insoluble in the aqueous phase of the pulp of nitric oxide NO:

2NO+O2=2NO2.

Subsequent contact NO2with NO and water vapor and pulp is riodic to the formation of nitric acid and reactive oxidant, as nitrous acid, HNO2:

2NO2+H2O=HNO3+HNO2;

NO+NO2=N2O3;

N2O3+H2O=2HNO2.

Thus, there is a continuous regeneration of nitric oxide with oxygen as oxidant in HNO3(and HNO2)that allows the use of NO as a catalyst for the oxidation of vanadium (2+) (3+) vanadium (4+), and sulfides.

Received leached slurry is separated using a filter on the liquor content, g/l: 2,6 V; 0,15 U; 0,17 Mo; 0,28 Σ which is sent to the first stage leaching is relatively easily soluble parts of vanadium and excess sulfuric acid, and the insoluble residue, which is washed with (a part of the mother liquor sorption of REE and additionally water). Then, the washing water is served on the second stage of leaching, and the washed insoluble residue sent for recycling in a known manner. The residual content in the insoluble residue, %: 0,03 V; 0,003 U; 0,006 Mo; 0,0128 Σ.

Thus, the degree of extraction of shale ore target metals in the pregnant solution, %: 92,8 V; 91,2 U; 90,8 Mo; 81,2 Σ.

Exhaust nitrous gases of the second stage leaching clear of nitrogen oxides in a known manner and the resulting nitrogen-containing substances are served by autoclave leaching. So, the content is existing in the exhaust gas nitrogen oxides convert (regenerate) in nitric acid in a known manner, for example, described in patent US 6264909, Drinkard, 24.07.2001.

This method of regeneration of HNO3involves the oxidation of nitric oxide 5-65%nitric acid:

4NO(g)+2HNO3(in)→3N2O3(b)+H2O

with the formation of the oxide from the oxidation of nitrogen equal to 3.

In the case of the presence of additives dissolved in the aqueous phase of such catalysts, as nitrite ionsNO-2or N2O3the reaction of NO oxidation proceeds rapidly and quantitatively.

Simultaneously in the aqueous phase flows through the redox reaction between dissolved N2O3and O2:

N2O3(in)+O2(in)+H2O→2HNO3(in)

and the response:

3NO2(in)+H2O→2HNO3+NO(in)

2NO2(in)+H2O→HNO3+HNO2

with the formation of nitric and nitrous acids, which are used for autoclave leaching of vanadium and other target metals.

Thus, the regeneration of nitric acid allows you to provide a return (recycling) of its principal amount (not less than 75-80%) in the process of leaching the ore.

From the pregnant solution containing ≤130 g/l of sulfate ions, first extract by anion-exchange sorption together with uranium and molybdenum at a pH of 1.8 to 2.2 and ORP solution of about 430 mV and a temperature not above 60°C. as a sorbent can be the used in particular, the anion exchange resin AMP or Ambersep 920.

Saturated with uranium and molybdenum anion exchange resin are sent to their desorption and obtaining uranium and molybdenum products by known methods. The regenerated anion exchange resin return on the operation of the sorption of uranium and molybdenum.

In the mother solution, sorption of uranium together with the molybdenum containing 3 mg/l U, 4 mg/l Mo and having a pH of 1.8 to 2.2, oxidize vanadium (4+) to vanadium (5+) by bringing the ORP of the solution to 750-800 mW using, in particular, hydrogen peroxide. The concentration of H2O2in the solution may range from 1.0 to 1.5 g/l and a flow rate of 60%H2O2about 1 l/m3. After that absorb vanadium (5+) at a temperature not exceeding 60°C, in particular, the anion exchange resin Ambersep 920.

Then saturated vanadium up to 350 kg/t of anion exchange resin Donatist vanadium up to 650 kg/t with part V of decorativ or vanadium-containing solution obtained by dissolving a certain amount of crystals metavanadate ammonium, preferably their fines. Considine of the anion vanadium greatly pre decarbonate of his limited impurities including phosphorus.

Subsequent desorption of vanadium in a known manner, for example, at a temperature of 30-35°C with solutions of ammonium nitrate (150-200 g/l), brought to pH 8.5 with ammonia, allows you to achieve virtually the ski quantitative solid-phase desorption of vanadium (99%) obtaining crystals of metavanadate ammonium NH 4VO3(MVA) of the desired high quality.

After desorption, the anion of the form nitrate translate (recharge) in the sulfate form by treatment with a solution of sulfuric acid and recycle on the operation of the sorption of vanadium.

Anion-exchange sorption using anion-exchange Ambersep 920 allows you to ensure the extraction of vanadium from the oxidized solution in the range of 96-98%, and the vanadium concentration in the mother solution is 60 to 80 mg/L. Considering the issue of reducing the concentration of vanadium in the mother solution at its anion-exchange sorption, it is necessary to note that when Cv≤1·10-3mol/l and pH 2-3 vanadium (5+is in cationic form VO2+forming unstable anionic complexes with sulfate ions VO2SO4-(see, Ivakin A.A., Voronova AM, J. Norgan. chem., 1973, V.28, No. 7, s). Only when the concentration of vanadium (5+in the solution flows through the reversible reaction of polymerization of dissocation VO2+with the formation of a stable decavanadate anions H2V10O284-

10VO+2+8H2O↔H2V10O284-+14H+

You should also consider not only the concentration of vanadium (5+in solution, but also the impact on the equilibrium of this reaction, and the presence in the solution of SO42-ions, the actuator is related to the decrease in the concentration of H 2V10O284-anions due to the formation of sulfate complexes with dioxaborinane vanadium (5+).

Maintaining in the mother solution, sorption of vanadium temperature up to 60°C leads to the destruction of residual hydrogen peroxide and reduction of the redox potential to ≤350 mV.

From mother solutions sorption produce vanadium cation exchange sorption of REE at pH 1.8-to 2.2, the AFP is not above 350 mV and a temperature not exceeding 60°C, in particular, cation exchange resin KU-2-8h or Ambersep 1200 N. the degree of REE extraction from the solution reaches ~98%, and their residual concentration in the mother solution, sorption 6-10 mg/L. Rich REE cation sent to their desorption and obtaining the target product in a known manner, and the cation exchanger after desorption recycle again to the operation of sorption. One part stock solution sorption of REE may apply to the washing of the insoluble residue from the liquor, and the other part - for recycling in a known manner, for example, to obtain alum or lime to precipitate impurities (Fe, Al, and others) and purified water to return it to the process (ore preparation, water washing the insoluble residue).

It should be noted that the ion exchange sorption and desorption of uranium, molybdenum, vanadium, REE is carried out in the units column type in the columns of the CPC, INPM, CDS and other fixed layer and the Nita, showed high efficacy (see Nesterov Y. Methods of processing multicomponent productive solutions. In kN. Underground leaching multi-element ores. Under. Ed. by Acad. Laverov N.P.): From the Academy of mining Sciences, 1998, s-224; Nesterov Y. Ion exchangers and ion exchange. Sorption technology in the extraction of uranium and other metals by the method of underground leaching. - M.: OOO UNICOR-IZDAT", 2007, s).

The total degree of extraction of the target metals on the operations of the leaching and sorption, %: 91,8 V; 94,2 U; 93,8 Mo; 78,2 Σ, i.e. in comparison with the method of the prototype, the degree of extraction of the ore, vanadium, uranium and molybdenum respectively 1.76, 1,26 of 1.88 and time when the specific consumption of sulfuric acid (about 140 kg/t ore), not exceeding such on the prototype method.

Thus, patent-pending method for processing carbon-siliceous black shale ores can significantly increase the degree of extraction of valuable metals such as vanadium, uranium, molybdenum, and increase the complexity of application of ore due to the additional associated for rare-earth product with a relatively high degree of extraction of the sum of the REE (~78%).

1. Method for integrated processing of carbon-siliceous black shale ores containing vanadium, uranium, molybdenum, rare earth elements, including grinding the ore to cropnet the particles is not more than 0.2 mm, campaign oxidative acid leaching of the ore tetravalent vanadium, uranium, molybdenum, rare earth elements at atmospheric pressure obtaining sulphate pulp, air conditioning sulfate pulp to a pH of 1.8 to 2.2, dividing the pulp into a productive solution containing tetravalent vanadium, uranium, molybdenum and rare earth elements, and a solid phase, autoclave oxidative acid leaching of the solid phase of vanadium, uranium, molybdenum, rare earth elements at the final concentration of sulfuric acid 35-45 g/l, a temperature of 130-150°C in the presence of oxygen-containing gas and the substance that forms nitric oxide, as a catalyst for oxidation with oxygen getting leached pulp and waste gases containing nitrogen oxides, the separation of the leached pulp liquor containing vanadium, uranium, molybdenum, rare earth elements, which are served at the above-mentioned agitation leaching of ore at atmospheric pressure, and the insoluble residue, which is washed and sent for recycling, the supply mentioned autoclave leaching products purification of exhaust gases containing nitrogen oxides, and water from washing the insoluble residue, anion-exchange sorption of uranium together with the molybdenum from the pregnant solution with obtaining matchevaluator and anion exchange resin, rich in uranium and molybdenum, their desorption and obtaining uranium and molybdenum products, the oxidation of tetravalent vanadium to its pentavalent state in the mother solution, sorption of uranium and molybdenum and anion-exchange sorption of vanadium with obtaining stock solution and saturated vanadium anion exchange resin, the desorption of vanadium from the anion exchange resin and obtaining vanadium product, cation exchange sorption of rare earth elements from the mother liquor sorption of vanadium with getting the mother liquor and the cation exchanger, which is rich in rare earth elements, desorption them from the cation exchanger with obtaining rare earth production and disposal of the resulting mother liquor.

2. The method according to claim 1, in which the aforementioned agitation leaching at atmospheric pressure is carried out at a pH of 1.2-1.6, redox potential (ORP) 400-450 mV, the temperature of 60-70°C, the ratio of solid: liquid = 1:(1-2), duration 2-4 hours and the use of ferric ions as an oxidant.

3. The method according to claim 1, in which the aforementioned agitation leaching at atmospheric pressure is carried out at a pH of 1.3-1.5, ORP=400-430 mV, the temperature of 60-70°C, the ratio of solid: liquid = 1:1.5, duration 3 h, and the use of ferric ions as an oxidant.

4. The method according to claim 1, in which kondicionirovanie the sulphate pulp produced by processing it crushed the original ore or other alkaline neutralizer character.

5. The method according to claim 1, in which the mentioned autoclave leaching is carried out at ORP=430-470 mV, the ratio of solid: liquid = 1:(1.0 to 2.0), and duration of 2-3 hours

6. The method according to claim 1, in which the mentioned autoclave leaching is carried out at a temperature of 140°C, ORP=450-460 mV, the ratio of solid: liquid = 1:(1.0 to 2.0), and duration of 2-3 hours

7. The method according to claim 1, in which the substance that forms nitric oxide, use acid blend (89% HNO3), or nitric acid, or sodium nitrite.

8. The method according to claim 1, in which the separation of the air-conditioned pulp to a productive solution and the solid phase is produced by filtering.

9. The method according to claim 1, in which the separation of the air-conditioned pulp to a productive solution and the solid phase is carried out by condensation with obtaining clarified productive solution and thickened suspension, which is filtered with getting productive solution and solid phase in the form of a cake.

10. The method according to claim 1, in which the separation of the leached pulp liquor and insoluble residue produced by countercurrent decantation and then filtering the thickened suspension.

11. The method according to claim 1, in which the washing of the insoluble residue is produced on the filter mother liquor sorption of rare earth elements, and optionally water.

12. The method according to claim 1, wherein the anion-exchange sorbl the uranium together with molybdenum conduct of productive solution at a pH of 1.8 to 2.2, AFP=400-430 mV and a temperature not exceeding 60°C.

13. The method according to claim 1, in which the oxidation of tetravalent vanadium to its pentavalent state in the mother solution to produce hydrogen peroxide.

14. The method according to claim 1, in which anion-exchange sorption of vanadium from the oxidized mother liquor is carried out at a pH of 1.8 to 2.2, ORP=750-800 mW and a temperature not exceeding 60°C.

15. The method according to claim 1, in which cation exchange sorption of rare earth elements from the mother liquor vanadium sorption is carried out at a pH of 1.8 to 2.2, the AFP is not above 350 mV and a temperature not exceeding 60°C.

16. The method according to item 12, in which anion-exchange sorption of uranium together with molybdenum spend on anion exchangers AMP or Ambersep 920.

17. The method according to 14, in which anion-exchange sorption of vanadium spend on the anion exchange resin Ambersep 920.

18. The method according to item 15, in which cation exchange sorption of rare earth elements is performed on the cation exchange resin KU-2-8h or Ambersep n.



 

Same patents:

FIELD: metallurgy.

SUBSTANCE: method includes uranium sorption by anion exchange resin, uranium de-sorption from saturated anion exchange resin by sulphuric acid and obtaining finished product from strippant. Note that uranium de-sorption from saturated anion exchange resin is done by sulphuric acid solution with concentration 70-100 g/l with the presence of 1-2 mole/l of ammonia sulphate.

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.

1 tbl, 3 ex, 2 dwg

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: process engineering.

SUBSTANCE: invention relates to processing natural uranium chemical concentrate. Proposed method comprises concentrate leaching by nitric acid solution to obtain suspension, adding coagulant into suspension and suspension separation. Clarified solution is separated from residue and directed to extraction. Note here that polyacrylamide-based anion coagulant is used and suspension with said coagulant is subjected to permanent magnetic field effects. Coagulant concentration and duration of magnetic field effects are selected to ensure concentration of insoluble residue now exceeding 100 mg/l in clarified solution. In extraction from clarified solution, no antifloating emulsions are observed.

EFFECT: solution suitable for further extraction.

3 cl, 2 tbl

FIELD: chemistry.

SUBSTANCE: method involves leaching the concentrate with aqueous nitric acid solution at high temperature to obtain a pulp consisting a solid and an aqueous phase. The aqueous phase is then separated by filtration from the solid phase in form of uranium nitrate solution. Uranium is then extracted from the nitrate solution using tributyl phosphate in a hydrocarbon solvent. The extract is washed and uranium is re-extracted. Leaching is carried out by adding nitric acid and water in an amount which enables to obtain a nitrate solution in the aqueous phase of the pulp, said nitrate solution containing dissolved silicon in concentration of 2.5-3.7 g/l. The solid phase, which consists of insoluble concentrate residues, is separated by filtration from the solution which contains dissolved silicon, uranium in concentration of 170-250 g/l and nitric acid in concentration of 80-120 g/l. Filtration is carried out not more than 24 hours after leaching, preferably not more than 5 hours after leaching.

EFFECT: obtaining clean nuclear materials, suitable for producing uranium hexafluoride for enrichment.

2 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: method involves leaching in order to dissolve uranium when the concentrate reacts with nitric acid solution to obtain pulp from the concentrate. Uranium is then extracted from the pulp using tributyl phosphate in a hydrocarbon solvent. The extract is washed and uranium is re-extracted. Extraction is carried out from freshly prepared pulp which is obtained through direct-flow reaction at temperature 20-65°C of a stream of a suspension of the concentrate in water which is prepared beforehand and a stream of nitric acid solution with flow rate ratio which ensures nitric acid concentration in the pulp of 25-120 g/l. The period from the beginning of leaching to the beginning of extraction is not more than 10 minutes.

EFFECT: protection of extraction from formation of non-demixing emulsions, providing given purity of uranium from ballast impurities and obtaining raffinates which can be removed into underground collector sand layers.

2 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to ecology and is aimed at preventing environmental pollution and radiation poisoning. The method of converting waste uranium hexafluoride into uranium metal and calcium fluoride involves reaction of uranium hexafluoride and calcium metal, where gaseous uranium hexafluoride is fed into molten calcium metal by bubbling, and operating temperature is kept higher than the melting point of calcium fluoride.

EFFECT: invention enables conversion of toxic radioactive uranium hexafluoride into an non-volatile compact product which is safe for storage.

1 ex

FIELD: metallurgy.

SUBSTANCE: intensified extraction of underground water is performed from used underground gas generator through the main water drain wells. Then, there created is cone of depression in the section of used underground gas generator for minimisation of underground water level and maintenance of maximum depression in the section of used underground gas generator. Treatment of ash-slag masses is performed using the solvent injected to the used underground gas generator, and leaching and collection of rare metal dissolved in the solvent extracted from underground gas generator is performed in surface chemical complex.

EFFECT: minimisation of negative environmental impact of solvent at leaching of rare metals from ash-slag masses owing to restricting the migration zone of solvent to the rock mass beyond the limits of underground gas generator.

4 cl, 1 dwg

FIELD: metallurgy.

SUBSTANCE: silicate uranium ore is crushed and crumbled; further, it is leached with sulphuric acid with addition of nitric acid as oxidant. Uranium is extracted and refined from impurities using mixture of extragents. Also as mixture of extragents there is used synergetic mixture containing di(2-ethyl-hexyl)phosphoric acid - 0.05-0.075 mole/l, tri-alkyl-amine - 0.05-0.075 mole/l in hydrocarbon dissolver at ratio of volumes of organic and water phases VO-VW= 1-3÷6. Upon extraction organic phase saturated with uranium is washed with solution of sulphuric acid. Further, uranium is re-extracted with solution of coal-ammonia salts producing crystals of ammonia-uranyl-tri-carbonate and is filtered. Produced crystals are tempered to production of protoxide-oxide of uranium.

EFFECT: output of finished product in form of protoxide-oxide of uranium of high quality.

2 tbl, 2 dwg, 3 ex

FIELD: metallurgy.

SUBSTANCE: processing method of nitric-acid solution of regenerated uranium involves uranium (VI) extraction with tributyl phosphate in organic diluter; flushing of extract with nitric-acid solution and re-extraction of uranium. At that, removal of technetium from uranium is performed by shifting technetium (VII) to non-extracted quadrivalent state in flushing zone of extraction cascade with the use of flushing solution containing 0.1-0.2 mol/l of carbohydrazide and 0.05-0.15 mol/l of nitric acid. Extract is flushed at the ratio of flows of organic and water phases, which is equal to 10-15. Method can be implemented in two versions. As per the first version, used flushing solution is supplied to feed stage of extraction cascade and technetium is removed to raffinate. As per the second version, used flushing solution is a separate flow from which uranium is extracted by contact with flow of fresh extractant; organic phase is connected to initial uranium extract prior to supply to flushing zone, and technetium is removed to separate product the volume of which is 5 times less than the raffinate volume.

EFFECT: increasing separation efficiency of uranium and technetium.

9 cl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to the technology of producing compounds of rare-earth elements during complex processing of apatites, particularly extraction of rare-earth elements from phosphogypsum. The method involves preparation of pulp from phosphogypsum and sorption of rare-earth elements on a sorbent. The pulp is prepared from ground phosphogypsum and sulphuric acid solution with pH=0.5-2.5 until achieving liquid:solid ratio of 4-7. Sorption is carried out directly from the phosphogypsum pulp on a sorbent with sulphuric acid functional groups for 5-7 hours with solid:sorbent ratio of 4-7.

EFFECT: high efficiency of the method owing to higher extraction of rare-earth elements without a filtration step.

6 tbl, 6 ex

FIELD: metallurgy.

SUBSTANCE: method involves selective extraction of salts in volumes of nanopores of nanoporous conducting materials due to effect of electrostatic interaction of dipole moments of solvated ionic complexes of transition, rare-earth and actinoid elements with electric field of double electric layer of "nanopore wall - solution" boundary line. The method is implemented by subsequent filling of nanopore of nanoporous conducting material with the solution containing ionic complexes of transition, and/or rare-earth and/or actinoid elements, displacement from nanopore of ionic complexes of transition, rare-earth and actinoid elements weakly localised in nanopores by means of pressure of gases or liquids, by filling of nanopore with solution of inorganic acid of high concentration, and by extracting from nanopores of residual ionic complexes of transition, rare-earth and actinoid elements by means of pressure of gases or liquids. The above method can be implemented in an electrochemical cell.

EFFECT: obtaining cheap and competitive compounds of the above elements of high technical purity.

45 cl, 18 dwg, 4 ex

FIELD: metallurgy.

SUBSTANCE: invention can be used in the technology of obtaining the compounds of rare-earth metals at complex processing of apatites, and namely for obtaining of concentrate of rare-earth metals (REM) from phosphogypsum. Method involves sorption of rare-earth metals. At that, prior to sorption, phosphogypsum is crushed in water so that pulp is obtained in the ratio Solid : Liquid=1:(5-10). Sorption is performed by introducing to the obtained pulp of sorbent containing sulphate and phosphate functional groups, at the ratio of Solid : Sorbent=1:(5-10) and mixing during 3-6 h.

EFFECT: increasing REM extraction degree to finished product.

5 tbl, 5 ex

FIELD: metallurgy.

SUBSTANCE: method involves oxidation of micro production wastes at temperature of 550-650°C in air atmosphere for destruction of crystal latitude Nd2Fe14B so that Fe2O3, Nd2O3, Fe2B is formed and moisture and oil is removed. Then, anhydrous fluorides of rare-earth metals are obtained and their metallothermic reduction is performed for production of constant magnets. After oxidation from oxidated microwastes is completed, rare-earth metals are leached with nitric acid with concentration of 1-2 mol/l at temperature of 20-80°C. Obtained nitrate solutions containing rare-earth metals and impurity elements are processed with solution of formic acid with extraction of formiates of rare-earth metals in the form of the deposit cleaned from impurity elements, which includes iron, aluminium, nickel, cobalt, copper and other transition metals.

EFFECT: regeneration of rare-earth metals from production wastes of magnets and obtaining raw material containing rare-earth metals for reutilisation in production of rare-earth constant magnets.

2 cl, 2 tbl, 7 ex

FIELD: chemistry.

SUBSTANCE: invention relates to methods of extracting a concentrate of rare-earth elements from wet-process phosphoric acid, which is obtained in a dihydrate process of processing an apatite concentrate, and can be used in chemical and related industries. The method involves sorption of rare-earth elements and thorium contained in wet-process phosphoric acid at temperature 20-85°C, wherein the sorbent used is a sulphoxide cationite, washing the saturated sorbent with water, desorption of rare-earth elements and thorium with concentrated ammonium sulphate solution to form a desorbate, and treating the desorbate with an ammonia-containing precipitant in form of ammonium carbonate or ammonia gas, which is fed in two steps, wherein at the first step the precipitant is fed until achieving pH 4.5-5.0 with precipitation and separation of a thorium-containing precipitate, and at the second step - until achieving pH of not less than 7 with precipitation and separation of a concentrate of rare-earth elements.

EFFECT: invention increases extraction of rare-earth elements while obtaining a non-radioactive concentrate of rare-earth elements.

4 cl, 4 ex

FIELD: metallurgy.

SUBSTANCE: method to extract holmium (III) cations from nitrate solutions includes ion floatation using an anion-type surfactant as a collector. Besides, the collector is dodecyl sodium sulfate in a concentration corresponding to stoichiometry of the following reaction: Ho+3+3C12H25OSO3Na=Ho[C12H25OSO3]3+3Na+, where Ho+3 - holmium cation, C12H25OSO3Na - sodium dodecyl sulfate. Moreover, ion floatation is carried out at pH=6.6-7.4, which makes it possible to achieve 90% extraction of holmium from aqueous solutions of its salts.

EFFECT: higher extent of holmium extraction.

1 dwg, 1 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: invention relates to the method for production of pure lanthanum or its oxides from lean or industrial raw materials by method of ion floatation. The method to extract lanthanum La+3 cations from aqueous solutions of salts includes ion floatation using an anion-type surfactant as a collector. Besides, the collector is dodecyl sodium sulfate in a concentration corresponding to the stoichiometric reaction: La+3+3NaDS=La[DS]3+3Na+, where La+3 - lanthanum cation, NaDS - dodecyl sodium sulfate. Moreover, ion floatation is carried out at pH=7.8-8.1, which makes it possible to achieve 98% extraction of lanthanum from aqueous solutions of its salts.

EFFECT: higher extent of lanthanum extraction.

2 dwg, 1 ex

FIELD: metallurgy.

SUBSTANCE: method for extracting rare-earth elements from the technological and productive solutions containing iron (III) and aluminium, with a pH-0.5÷2.5, includes the sorption of rare-earth elements with strong-acid cation resin. As the strong-acid cation resin the microporous strong-acid cation resin is used based on hypercrosslinked polystyrene having a size of micropores 1-2 nm.

EFFECT: higher efficiency of the process due to greater sorption capacity of the said strong-acid cation resin, high kinetics of sorption and selectivity, improvement of the subsequent quality of eluates and simplification of the process of their further processing.

5 tbl, 5 ex

FIELD: metallurgy.

SUBSTANCE: method of phosphogypsum processing involves leaching of phosphogypsum with sulphuric acid solution with change-over of phosphorus and rare-earth elements to the solution, and gypsum residues is obtained, rare-earth elements are extracted from the solution and the gypsum residue is neutralised with the main calcium compound. In addition, leaching is performed with sulphuric acid solution with concentration of 1-5 wt %. After that, rare-earth elements are extracted from the solution by sorption using sulfocationite in hydrogen or ammonia form with further desorption of rare-earth elements with ammonia sulphate solution. After desorption to the obtained strippant there added is ammonia or ammonium carbonate with deposition and separation of hydroxide or carbon-bearing concentrate of rare-earth elements. Extraction of rare-earth elements of medium and yttrium groups to concentrates is 41-67% and 28-51.4% respectively. Specific consumption of neutralising calcium compound per 1 kg of phosphogypsum has been reduced at least by 1.6 times.

EFFECT: obtaining high-quality hydroxide or carbonate concentrate of rare-earth elements.

4 cl, 4 tbl, 4 ex

FIELD: metallurgy.

SUBSTANCE: method involves leaching rare-earth elements and phosphorus from phosphogypsum. Leaching is carried out using a bacterial complex consisting of several types of acidophilic thionic bacteria in the active growth phase, adapted for active transfer into the liquid phase of phosphorus and rare-earth elements. Leaching is carried out in tank conditions with bacterial population of 107 cells/ml, solid-to-liquid ratio 1:5-1:9, active or moderate aeration and temperature 15-45°C for 3-30 days.

EFFECT: high efficiency of the process of recycling phosphogypsum using a cheap and an ecologically safe method.

2 ex

FIELD: metallurgy.

SUBSTANCE: method involves distillation of vapours of molybdenum trioxide in vacuum at residual pressure of 1-15 mm Hg and condensation of formed vapours of molybdenum trioxide. Besides, initial tailings are dissolved in molten boron oxide. Distillation of vapours is performed from molten metal at temperature of more than 1350°C, and condensation of vapours is performed at temperature of 800-820°C.

EFFECT: simplifying the technology; improving the quality of trioxide owing to its obtaining in compact state; reducing the cost owing to reducing labour costs and power consumption; improving environmental conditions.

1 tbl, 2 ex

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