Method of extraction of rich components from production solutions for processing of black-shale ores

FIELD: metallurgy.

SUBSTANCE: method includes sorption of rich components from production solutions by ion-exchange material counterflow under controlled pH of environment and oxidation-reduction potential Eh. Sorption is performed by ion-exchange materials in stages from production solutions containing uranium, molybdenum, vanadium and rare earth elements. At the first stage uranium and molybdenum are extracted by anion-exchange material sorption. At the second stage vanadium is extracted by anion-exchange material sorption with hydrogen dioxide available at Eh of 750-800 mV, pH of 1.8-2.0 and temperature of 60°C, at that vanadium sorption is performed till complete destruction of hydrogen dioxide and till Eh is below 400 mV. Then barren solutions are transferred to cationite at pH of 2.0-2.5 and Eh of 300-350 mV for extraction of rare earth elements.

EFFECT: sorption concentration and selective separation of uranium and molybdenum from vanadium, and vanadium from rare earth elements, and rare earth elements from iron and aluminium, intensification of sorption process, reduction of flow diagram and possibility of environmentally sound oxidants use.

1 dwg, 4 tbl, 1 ex

 

The invention relates to the field of hydrometallurgy, namely, to methods for recovery of rare and radioactive elements.

A known method for concentrating uranium from dilute solutions, in which the sorption of uranium anion exchange resin, washing the anion exchange resin from impurities, Considine of the anion uranium by its contact with part of the uranium decorate, desorption of uranium acid-salt solutions and the deposition of the commodity decorate of pereskia uranium peroxide (patent RU No. 2404126, IPC C01G 43/00, publ. 20.11.2010).

The disadvantage of this method is the impossibility of selective separation of uranium from anionic impurities, reducing the intensity of the sorption process.

The known method for the selective extraction of uranium from ores in which the ore is subjected to after grinding the leaching to produce pulp at a pH of 4.2-2.2 and later at pH 4.6-2.0 leaching combined with countercurrent sorption of uranium, while maintaining the desired value of temperature and pH in the course of the pulp. As the oxidant used manganese compounds, desorption of uranium from a busy ion exchanger exercise sulfate solutions (patent RU NO. 2094512 MPC SW 60/02, publ. 27.10.1997).

The disadvantage of this method is the absence of selective separation of uranium from anionic impurities, and the introduction as oxidant compounds manganese does not allow you to keep the van is Dios in oxidation state (+IV) and to achieve selective extraction of valuable components (uranium and molybdenum).

The method for extracting uranium, molybdenum and vanadium from ores, which includes grinding and leaching of valuable components of mineral acid and subsequent sorption extraction of dissolved uranium, molybdenum and vanadium from the pulp. Before leaching the crushed ore in the form of an aqueous slurry oxidized by treatment with anion exchange resin in OH-form at pH 8.5-11.6, redox potential (ORP) -50 to +150 mV at a temperature of 30-80°C, and the leaching and sorption extraction of lead by adding oxidized slurry with sulfuric acid to pH 1.5-3.5 and anion exchange resin in the sulfate form (patent RU №2211253, IPC SW 60/02, publ. 27.08.2003).

However, this method does not allow to oxidize compounds of rare metals in the lower degrees of spinelide black shale anion exchange resin in OH-form.

The technical result of the invention is a sorption preconcentration and selective separation of uranium and molybdenum from vanadium and vanadium from rare earth elements and rare earth elements from iron and aluminum, the increasing intensification of the sorption process, the reduction of the technological scheme and the use of environmentally friendly oxidants.

The technical result is achieved by the method of extraction of valuable components from the pregnant solution processing of black shale ores, including sorption of valuable components in the Otok exchange resin at controlled pH solutions and redox potential Eh, this sorption was carried out multi-stage ion from the pregnant solution containing uranium, molybdenum, vanadium and rare earth elements in the first stage adsorption on the anion exchange resin extract the uranium and molybdenum, in the second stage adsorption on the anion exchange resin extract the vanadium in the presence of hydrogen peroxide at Eh 750-800 mV, pH of 1.8-2.0 and at a temperature of 60°C and lead sorption of vanadium to the complete destruction of hydrogen peroxide and to lower Eh below 400 mV, then the manifold sorption sent to the cation exchanger at a pH of 2.0 to 2.5 and Eh 300-350 mV for extraction of rare earth elements.

The proposed method includes the interaction in the sorption column in counter-current with the complex anion salt solutions, and the interaction is carried out in a variable interval of values of redox potential (Eh) and pH of the environment in which the extracted metals are dissolved.

The initial composition of the solution entering the sorption redistribution shown in table 1

Table 1
pH 1,2Eh 350-450 mVSalinity 220-280 g/l
Components
H2SO4VO2+UO22+MoO22+REE3+PO43-Fe3+Al3+
Content, g/l153,50,150,200,302,58-1212-15

Shows the composition of the ionic forms of the elements in the solution does not allow to choose one property and on its basis to create technology for complex extraction and separation. To resolve this issue, you must apply a number of combined techniques of chemistry. It is known that the behavior of multivalent ions of elements in solutions depends on the ionic potential, determined by the ratio of charge to ionic radius. Figure grouped properties of rare metals, depending on the ionic potential. Metals with ionic potential is less than 3-cations (8-electron configuration in the outer shell). Metals with very high ionic potential - more than 10, form a stable complex anions with covalent bonds: (PO4) , (VO4)3-UO22+, MoO22+. At ion potential 3-10 are metal ions with amphoteric properties. In addition, it is known that Eh and pH affect poliyadernogo ionic forms and the kinetics of their mutual transition.

The method of extraction of valuable components from the pregnant solution processing chernoslantsevykh ores for the extraction of uranium, molybdenum, vanadium and rare earth elements is that in the first stage sorption oxidation of uranium and molybdenum hold iron (+III) and vanadium (+IV), and the second stage sorption oxidation of vanadium (+IV) are hydrogen peroxide, and sorption of rare earth elements is carried out after the destruction of the peroxide.

Concentration and selective extraction of uranium and molybdenum on an anion exchange resin, moved countercurrent to the solution, leading to the conditions under which Eh support wustite iron (Fe2+within 350-400 mV (Fe3+/Fe2+=20:1) and pH 1.0 to 1.5, vanadium reliably retained in solution in the form of a pair of V4+/V3+that prevents V5+.

The occurrence of vanadium in the highest degree of oxidation caused by two unwanted process, on the one hand, the transition of vanadium on the anion exchange resin together with uranium and molybdenum (broken selectivity of the process), and on the other hand, the precipitation of sparingly soluble is integral salts of iron and vanadium. At lower Eh less than 350 mB decreases the intensity of sorption extraction, and increasing Eh more than 400 mB and pH more than 1.6 leads to the precipitation of sparingly soluble salts.

Selective separation of vanadium from rare earth elements is achieved by the introduction of hydrogen peroxide (H2O2), playing the role as oxidant and reductant. When the concentration of H2O21.0-1.5 g/l or redox potential Eh 750-800 mV and a pH of 1.8-2.0 vanadium is extracted from the solution to the content of 0.008 g/L. In the process of adsorption of vanadium at a temperature of 60°C is the destruction of vanadium peroxide, the hydrogen peroxide is removed and the solution Eh decreases to values less than 400 mV.

An example of the method.

Take a productive solution, whose composition is given in table 1., spend countercurrent sorption column filled with anion exchange resin S-p in the amount of 10 ml at pH 1.2 and Eh 400 mV in a dynamic environment, and ignore the 1 liter of solution. The mother liquor sorption control on the content of uranium (U) and molybdenum (Mo). The process of sorption finish when the content in the manifold U is not more than 4 mg/l and Mo 8 mg/liter Resin contains U 14.5 kg/t and Mo 17.5 kg/so

Further, the mother liquor sorption containing 3.5 g/l V2O5, is treated with a solution of KOH to pH 1.9 and hydrogen peroxide (H2O2the rate of 1.0 g/l to Eh 750 mV. The solution is passed through a new batch of the Academy of Sciences of Anita to a residual content of V 2O5in the manifold is not more than 0.01 g/L. the Process of sorption is carried out at a temperature of 60°C until complete destruction of the H2O2and lowering Eh less than 400 mV. The Queen cells sorption is passed through a cation exchange resin Ku-2 at pH 2.0 to 2.2 and Eh 300-350 mV for extraction of rare earth elements (REE). Removing Σ REE is about 90%.

The results of the sorption of metals are given in table 2, 3, 4

Table 2
The results of sorption extraction and separation of uranium and molybdenum from vanadium.
The mother liquor sorptionThe content on the anion exchange resin
Eh, mVpHUMoV2O5, g/lFeAl, g/lREE, g/lCC*, g/lThe ratio of Fe3+/Fe2+, g/lU Mo
mg/lWCI-e %mg/lWCI-e %Fe3+, g/lFe2+, g/lkg/t%kg/t%
3501,215,090,026,089,63,55,20,59,20,3114110,413,59017,487
4001,24,097,424,090,43,55,30,289,10,2515018,914,697,31,6 88
4501,22,098,721,0to 91.63,55,30,259,00,2614021,014,898,617,9to 89.5
4001,0to 12.092,025,090,63,55,20,209,10,2514326,013,892,0of 17.587,5
4001,253,098,021,0to 91.63,55,20,22 9,00,2415523,614,798,017,9to 89.5
4001,51,099,318,092,83,55,20,239,20,2315022,614,999,318,291
*CC - salinity

Table 3
The results of sorption extraction and separation of vanadium from rare earth elements (REE)
The original solutionThe mother liquor sorptionThe content on the anion exchange resin
H2O , g/lVREE, g/lFeAl, g/lP, g/lCC*, g/lV2O5
Eh, mVpHmg/lWCI-e %Fe3+, g/lFe2+, g/lkg/t%
7001,81,00,00997,30,225,30,0019,12,41140349,199,7
7501,81,50,00698,10,215,30,0029,02,34150 349,499,8
8001,82,00,00599,00,225,3-9,02,42142349,599,85
7501,62,00,00897,30,225,30,0019,12,45138349,299,7
7501,82,00,00698,10,225,3-9,22,35139349,499,82
7502,02,099,00,225,3-9,02,28138349,599,85
CC* - salinity

Table 4
The results of sorption extraction and separation of REE
Eh, mVpHThe mother liquor sorptionThe content on the anion exchange resin
REEFeH2O2, g/lREE
mg/lWCI-e %Fe3+, g/lFe2+, g/lkg/t%
3002,01892.05,1 0,21-20,292.0
3502,02290.05,00,18-19,890.0
4002,02688.05,00,20-19,488.0

The method of extraction of valuable components from the pregnant solution processing of black shale ores, including sorption valuable components by countercurrent exchange resin at controlled pH environment and redox potential Eh, while sorption was carried out multi-stage ion from the pregnant solution containing uranium, molybdenum, vanadium and rare earth elements in the first stage adsorption on the anion exchange resin extract the uranium and molybdenum, in the second stage adsorption on the anion exchange resin extract the vanadium in the presence of hydrogen peroxide at Eh 750-800 mV, pH of 1.8-2.0 and at a temperature of 60°C, and the sorption of vanadium lead to the complete destruction of hydrogen peroxide and to lower Eh below 400 mV, after h is a manifold sorption sent to the cation exchanger at a pH of 2.0 to 2.5 and Eh 300-350 mV for extraction of rare earth elements.



 

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3 ex, 1 tbl

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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: 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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