Method of integrated processing of magnesium-chrome crude ore
SUBSTANCE: invention can be used for production of high-purity silicon dioxide within integrated processing of magnesium-chrome crude ore that is mixed serpentinite, chromite, pyroxene and other minerals. Method of integrated processing of magnesium-chrome crude ore includes as follows. Crude ore is decomposed by solution of mineral acids. Produced suspension is filtered, and insoluble residue is processed. Filtrate neutralisation is accompanied with sedimentation of contained metal hydroxides with washing and drying of produced end-products. Processing of insoluble residue includes annealing at temperature 350-600°C, following dissolution in caustic soda to residual alkalinity 40-60 g/l NaOH, filtering of prepared suspension, washing of residue that is chrome ore concentrate and sedimentation of silicon dioxide from produced filtrate with solution of hydrochloric acid to residual acidity 2-15 g/l HCl.
EFFECT: higher separation integrity of silica component with simultaneous integrated extraction of other components of crude ore that provides extended application of base mixtures.
6 tbl, 2 ex
The invention relates to the field of hydrometallurgical processing of non-metallic minerals and can be used to obtain high-purity silicon dioxide (analog white soot) in the processes of complex processing magnirostris ore raw materials (a mixture consisting of serpentinite, chromite, pyroxene, chlorite and other minerals).
When processing natural or man-made materials, which includes silica (SiO2) or silicon dioxide in the form of silicic acid (SiO2×nH2O), silica component has traditionally been viewed as ballast and troublesome part. However, in various industries in large quantities, highly dispersed amorphous silicon dioxide, which is produced on the basis of the acid processing of expensive liquid glass.
There are a number of minerals such as nepheline, eudialyte, feldspar, olivine, serpentine and others, acid and alkaline decomposition which is accompanied by a translation into the solution not only of metal salts, and silica in the form of silicic acid. Therefore, in the processing of such raw materials, the actual problem is the allocation of the silica component in the form of a high-quality product is silicon dioxide, widely used in several industries - electron is Oh, chemical, tire, etc. to obtain silicate materials with unique properties: fiber optic cable (device for the directional transmission of light energy), semiconductors, additives to improve the physical-mechanical properties of polymers and rubbers and other
There is a method of processing non-metallic minerals, in particular acidic mineral wool rock (pumice stone or obsidian), with the aim of obtaining silicon dioxide, including the grinding, leaching with alkali solution (concentration 130-260 g/l NaOH) at 100-180°and the ratio of W:T=1:(2-4), filtering the suspension, electromagnetic processing of the filtrate to clean from micaceous iron impurities, the deposition of the gel, silicic acid from the filtrate a solution of mineral acids (hydrochloric or nitric) to pH=6,5-7,0 followed by filtering the suspension, washing and drying silicon dioxide. (SU 1791383 A1, 01 33/12, publ. 30.01.1993,)
However, using this method of processing for minichromosomes of ore containing magnetic and non-magnetic minerals type of fibrous asbestos, forsterite, chlorite, pyroxene, chromite, etc., inefficient, because the electromagnetic method of purification of the filtrate (liquid glass) from the undecomposed part of the raw materials will not allow to obtain a high yield of silicon dioxide with a low content of impurities.
The known method p is rerabotka silicate raw materials, in particular nepheline concentrate, including: the decomposition of raw materials with sulfuric or hydrochloric acid (5,0-30,0%concentration), filtering the suspension, heat treatment (dehydration) of the filtrate 80-300°With, cleaning digidratirovannogo product from impurities leaching with hot water or weak acid solution, filtering the suspension, and separating the silica from the liquid phase, drying and packing of the finished product. (EN 2179527, IPC 01 33/187, publ. 20.02.2002,)
The finished product is characterized by good physical and chemical properties: large specific surface (not less than 100 m2/g) and high silicon dioxide content (not less than 90%).
The shortcoming of the above method is that it is suitable for processing of mineral raw materials, well-degradable weak solutions of mineral acids (5,0-30,0%concentration), such as nepheline, eudialyte, feldspars and other minerals, with the formation of water-soluble silicates of potassium or sodium, and may not be used in the processing of the serpentine-chromite ore mixture, because the minerals that are included in its composition (chromite, chronicity, olivine, pyroxene, forsterite, and others), such weak solutions of acids is practically not opened.
The closest in technical essence analog is the way complex processing of the hammer is of TINIT.(RU # 20973322, IPC 01 33/142, publ. 27.11.1997,)
The method consists in the following.
Crushed to particle sizes 0,074 mm serpentinite decompose sulfuric acid concentration of 20-50%, and filtering the resulting suspension. In the first stage receive the precipitate, consisting of amorphous silica and undecomposed minerals, and the filtrate. The residue is subjected to magnetic separation to separate chromomagnetic concentrate from silicon dioxide. The filtrate is neutralized to pH 7.0-8.5 in, precipitated hydroxides of Fe3+, Al3+, Cr3+, Ni2+. Of the remaining filtrate by the method of carbonization, followed by sedimentation and filtration, receive magnesium carbonate, which calcination is transferred to burnt magnesia, sintered or fused periclase. Silicon dioxide, after the electromagnetic separation from undecomposed raw materials washed from water-soluble salts, dried and calcined.
The finished product is characterized by a high content of SiO2:
- not below 87,7% (dried at 105°),
- 99,0% (calcined at 900-1000°).
Reasons preventing the wide use of the above method are as follows:
- the method of separation of part of undecomposed raw materials from silica magnetic separation can be used in the processing of ore mixtures containing minerals with magnetic properties is. For example, such as magnetite, avenet and other minerals, as well as chronicity and chromite-rich inclusions of iron oxides FeO and Fe2About3. It is the presence of chrome-spinel impregnated iron oxide imparts magnetic properties;
- application of the method of magnetic separation to separate the poor chromite ore mixtures containing non-magnetic or weakly magnetic minerals type serpentinite, olivine, pyroxene, chlorite, etc. is not economically feasible because it requires the use of expensive, complex and inefficient equipment. It was established experimentally that even the use of such equipment for the electromagnetic separation of the precipitate after leaching serpentine-chromite ore mineral acid does not guarantee the obtaining of silicon dioxide that is free of impurities (like 1);
- leaching of serpentinite particle size less than 0,074 mm creates great difficulties for filtering suspensions and requires additional costs for grinding the ore mixture.
An object of the invention is to develop a cost-effective method for integrated processing of minichromosomes ore raw material that ensures maximum extraction of valuable components of raw materials (magnesium, chromium, silicon, manganese, iron) and receipt of any of serpentine ru is different mixtures (including from such which do not contain minerals with magnetic properties) highly dispersed silicon dioxide.
The technical result from the use of the invention is to provide the most complete selection of raw materials silica component with simultaneous integrated extraction of valuable components of the raw material that ensures expansion of the use of poor ore mixtures.
The technical result is achieved due to the fact that in the method for integrated processing of minichromosomes of ore, including the decomposition of the raw material solution of a mineral acid, filtering the resulting suspension, the processing of the insoluble residue, the neutralization of the filtrate from the precipitation of hydroxides contained metals, washing and drying the resulting final products, processing of the insoluble residue is firing it at a temperature of 350-600°C, followed by dissolution in caustic soda with a residual alkalinity of 40-60 g/l NaOH, filtering the resulting suspension, laundering sediment - chromite concentrate, and deposition of silicon dioxide from the resulting filtrate with hydrochloric acid to a residual the acidity of the mother liquor 2-15 g/l HCl.
The method is as follows: natural serpentine-chromite ore mixture (mineral and chemical composition see table 1) are ground to a particle size IU is 2 mm and leached mineral acids (sulfuric 40-42% H 2SO4or a salt 10-20% HCl at 60-80°in the ratio t:W in the reaction zone 1:(2,5-4,0) for 1-2 hours until the residual acidity in suspension (4,0-6,0 g/l H2SO4or 1.0-3.0 g/l HCl). After that, the suspension is filtered.
The filtrate is a solution of sulphate (chlorides) of magnesium, iron, aluminium and manganese neutralized in 2 stages: up to pH=7.0-8.5 in order to precipitate the hydroxides of Fe3+, Al3+, Cr3+, Mn2+and to pH=9,0-11,0 to obtain magnesium hydroxide. The neutralization is carried out with a solution of soda ash.
From hydroxides of Fe3+, Al3+, Cr3+, Mn2+get modified micaceous iron pigments and hydroxide of Mg2+- periclase.
To obtain high-purity silicon dioxide, free of impurities chromite, pyroxene and other minerals, insoluble residue - KEK 1, obtained after sulfuric acid (or hydrochloric acid) leaching the ore mixture containing a mixture of amorphous silica and nerastvorim minerals (chromite, pyroxene, chlorite, and others), washed from water-soluble salts (sulfates or chlorides), dried at 105-110°C, calcined at 350 to 600°C for 2 hours to dehydration cake, dehydration of silica SiO2×4H2O and destruction of the structure of amorphous silica (table 2, 3, 4 shows the mineral and disperse the chemical composition of nearest Oronogo balance - cake 1). It is established that silicon dioxide (silica) after this treatment gets increased ability to dissolve in alkali.
Next KEK 1 is treated with sodium hydroxide solution (concentration 140-180 g/l NaOH) for 15-30 minutes at 50-70°and the ratio of t:W=1:4, to the content of NaOH in suspension not less than 40-60 g/l, the Suspension is filtered, the insoluble residue - chromite concentrate, cleaned from impurities by repulpable in hot water, dried and stariway. The finished product contains not less than 55,0-58,0% Cr2About3.
The filtrate, after separation of chromite concentrate, the so-called silica solution in caustic soda (or water glass), NaOH concentration of not less than 40% is treated with hydrochloric acid solution (20% HCl) at 70% to a residual acidity in the mother solution of 2.0-15.0 g/l HCl. The suspension is filtered, the precipitated residue of silica is separated from the mother liquor of sodium chloride by filtration, washed from water-soluble salts with hot water and repulpable, dried at 105°C, calcined at 900°and stariway. To obtain high purity silicon dioxide, containing a minimum concentration of impurities precipitate silica washed so much water that the amount of wash water would be 1.8 to 3.0 times the amount of the filtered suspension.
The finished product is characterized by high physical and mechanical properties of the (see table 5, 6).
Table 1 presents the mineral and chemical compositions of the original serpentine-chromite ore mixture.
2, 3 shows the mineral and chemical composition of the insoluble residue (cake 1).
In table 4 - mineral and chemical composition of non-magnetic product, the resulting electromagnetic separation of amorphous silica from undissolved minerals in the cake 1.
In table 5 the technological parameters of process of separating silica from alkaline solutions.
In table 6 the physical-chemical properties of silicon dioxide, obtained by the claimed method and calcined at 900°C.
Example 1 (poor serpentine-chromite ore conducted by the technology prototype):
1000 grams of serpentine-chromite ore mixture, the particle size is 0,074 mm is treated with a solution of sulfuric acid concentration of 520 g/l at 80-90°C for 2 hours. The suspension is filtered with the filtering rate = 0,021 cm/min, the Filtrate is sent for further processing to identify valuable components: magnesium, iron, aluminum and other Insoluble residue (KEK 1) the weight equal to 530 g consisting of amorphous silicon dioxide and part of nerastvorimogo raw, washed with hot water repulpable and sent for electromagnetic separation with the aim of separating silica from chromite, magnetite is in, pyroxene and other minerals (mineral and chemical composition of the insoluble residue, dried at 105°With, before and after electromagnetic separation - see table 2-4).
Electromagnetic separation carried out on a laboratory rotary separator with special cassettes, in which the separated mixture is divided into magnetic and non-magnetic products. After the electromagnetic separation of non-magnetic product is dried and the quality of the finished product stariway.
Comparing tables 2, 3, 4, it is seen that the electromagnetic separation of cake 1 does not lead to a complete separation of silica from undecomposed minerals and as a result cannot provide high-quality silicon dioxide (the quality of the finished product, see table 6).
In addition, the disadvantage of this technology is the very low rate of filtration of the suspension (0,021 cm/min), the reason of which is the fine grinding of the original ore mixture fed to the leaching.
Example 2. 1000 g of serpentinous ore mixture (composition see table 1) particle size of 2 mm is treated with a solution of sulfuric acid (3.7 litre, the concentration of 42% H2SO4). The suspension is filtered with a speed of 2.1 cm/min, the filtrate is sent for further processing to obtain oxides of Fe3+, Al3+, Mg2+and the insoluble residue (a mixture of amorphous oxide, PU glue, which I chromite and other minerals (see table 2, 3)) weight 480 g of thoroughly washed from the sulphates of iron, magnesium and other soluble salts, dried at 105°C and calcined at 550°C. After the heat treatment KEK 1 is dissolved in caustic soda for 30 min at 70°and t:W=1:4, to the content of NaOH in the besieged solution (suspension) - 49,0 g/l, the Suspension is filtered, the insoluble chromite concentrate is cleaned from impurities, dried and stariway. The filtrate is "liquid glass", the concentration is 49.0 g/l NaOH precipitated by hydrochloric acid with a solution of 20% HCl at 70°to a residual acidity in the mother solution of 10.2 g/l HCl. The suspension is filtered with the filtering rate of 2.1 cm/min. and the precipitation of the silica is washed with hot water of 2.1 times the amount of the filtered suspension. Next, the washed silica dried at 105°and calcined at 900°C. the quality of the finished product are shown in table 5, 6.
Example 3. Mass, mineral, chemical and dispersion compositions of the ore mixture similar PR, the mixture is treated with 3.7 liters of hydrochloric acid (concentration of 220 g/l HCl), the filtrate is sent for further processing to obtain oxides of Mg2+, Fe3+and others, and the insoluble residue weight 530 g washed from the chlorides of magnesium, iron and other soluble salts, dried at 105°C and calcined at 600°C. Next, the insoluble residue is treated with the Birmingham, similar PR.
Properties of silicon dioxide, see table 5, 6. From table 5 and 6 shows that the leaching process serpentine-chromite ore mixture is preferable to carry out the sulfuric acid solution.
Example 4. Mass, mineral, chemical and dispersion compositions of the ore mixture and sulfuric acid concentration and temperature of baking cake 1 similar PR. Changed the concentration of NaOH in the besieged suspension - 60,0 g/l NaOH, and the thoroughness of washing the silica with hot water: the volume of wash water was 3.0 times the amount of the filtered suspension, after washing the slurry on the filter were repurpose. The result was obtained silicon dioxide maximum purity is the content of SiO2=99,97%.
Example 5-13. Leaching was carried out with sulfuric acid with different variations:
- temperature baking cake 1 - 300-700°C
the concentration of NaOH in the besieged suspension - 32,2-70,0 g/l,
residual acidity of HCl to 1.0-16.0 g/l,
- the relationship of the volume of wash water to the volume of the filtered suspension - 1,0-3,0 + repulpable.
As can be seen from table 5:
1) the speed of filtration of silica suspensions depends on:
- temperature firing cake 1 (when the firing temperature below 350°and above 600°With the rate of filtration decreases),
- the concentration of NaOH in the besieged suspension (NaOH content below 40 g/l filtering rate is practically equal to zero, the use of suspension with NaOH concentration above 60 g/l is not economically feasible);
2) the silicon dioxide content in the calcined silica at 900°depends on the residual concentration of hydrochloric acid in the mother filtrate (2-15 g/l HCl) after deposition of silica and the amount of wash water, which should be 1.8-3 times the volume of the filtrate. The use of a suspension of the HCl concentration in the mother solution above 15.0 g/l HCl is not economically feasible, and less than 2 g/l leads to a low content of silica in the final product and high content of impurities (oxides of Fe3+, Cr3+, Al3+, Mg2+Cs2+and other (see table 6)).
At low filtration rate (op, 10) sediment practically not formed and all silica component remains in the mother solution.
|Mineral and chemical composition of serpentine-chromite ore mixture|
|Name of minerals||Sod-e %||Name of the components and their content, %|
|2. Olivine (forsterite)||8,0||0,08||3,47||3,6||0,5||-||-||0,16||-|
|3. Chromite (chronicity)||10,0||1,5||1,0||0,05||2,5||5,98||-||-||-|
|The mineral composition of the insoluble residue (KEK 1)|
|Name of minerals||Content, %|
|1. Chronicity (chromite)||18,9|
|2. Forsterite (olivine)||the 3.8|
|5. Quartz||the 3.8|
|The chemical composition of the insoluble residue (KEK 1)|
|Name of the component||Content %|
|7. unrecorded, SPT||2,74|
|Mineral and chemical compositions of the non-magnetic product|
|Name of minerals||sod-e %||Name of the components and their contents in %|
|SiO2||Al2O3||CaO||MgO||Cr2About3||Fe2About3||MnO||volatile and ignoramus.||H2O|
|5. roentgen amorphous phase||95,5||79,56||0,54||0,87||1,18||0,23||0,46||0,01||-||-|
|Technological parameters of the process of separating silica from alkali solutions|
|no examples||The firing temperature of cake 1, °||The concentration of NaOH in the besieged suspension, g/l||Residual concentration of HCl in the fallopian R-re, g/l||The rate of filtration of a suspension of silicon dioxide in caustic soda, cm/min||The ratio of the volume of wash water to the volume of the filtered suspension||The content of SiO2in the sediment, %|
|dried at 105°||calcined at 900°|
|1||The experiment was conducted on technology prototype||2,0||82,0||89,43|
|4||550||60,0||15,2||2,3||3.0 + repulpable||94,36||99,90|
|7||350||53,6||10,4||1,35||3.0 + repulpable||86,4||91,26|
|8||300||55.0||15,8||0,88||3.0 + repulpable||50.15||58,64|
|12||700||50,0||15,0||1,1||3.0 + repurpose/td>||at 88.1||93,51|
|13||600||60,0||16||2,5||3.0 + repulpable||95,1||of 99.97|
|Physico-chemical properties of silicon dioxide, calcined at 900°|
|Defined indicators||no examples|
|1. Mass fraction of SiO2, %||89,43||99,57||98,29||99,99||82,3|
|2. Mass fraction of moisture, %||-||-||-||-||-|
|3. Loss in weight on ignition||-||-||-||-||-|
|4. Mass fraction of iron in terms of Fe2O3, %||of 2.26||0,09||0,04||0,01||3.1|
|5. Mass fraction of aluminum in terms of Al2O3, %||1,02||0,03||0,1||0,06||5.4|
|6. Mass fraction of chlorides or sulphates, %||2,49||0,02||0,08||0,02||2,3|
|7. Mass fraction of calcium-magnesium in terms of Cao, %||3,60||0,18||1,28||0,01||5,2|
|8. Mass fraction of chromium in terms of Cr2O3, %||1,2||0,11||0,21||no||1,7|
|9. Specific surface area by VET, m2/g||56,0||341,0||327,9||351,0||to 12.0|
|10. the pH of aqueous extract||7,5||7,0||5,5||8,0||7,8|
Method for integrated processing of minichromosomes of ore, including its decomposition solution of mineral acid, filtering the resulting suspension, the processing of the insoluble residue, the neutralization of the filtrate from the precipitation of hydroxides contained metals, washing and drying the resulting end products, characterized in that the processing of the insoluble residue is firing it at a temperature of 350-600°C, followed by dissolution in caustic soda with a residual alkalinity of 40-60 g/l NaOH, filtering the resulting suspension, laundering balance - chromite concentrate and deposition of silicon dioxide from the resulting f is ltrate solution of hydrochloric acid to a residual acidity of 2-15 g/l HCl.
SUBSTANCE: invention concerns hydrometallurgy and ore benefication, extraction of nonferrous, less-common and noble metals from sulfide minerals, reprocessing of ore, concentrates and withdrawals of ore-dressing and metallurgical manufacturing, including concentrates, middlings, tails, slags, sludges and others. Technical effect of current invention is increasing of metals extraction from concentrates, decreasing of leaching time, decreasing of energy consumption used for leaching. Method of hydrometallurgical reprocessing of sulfide concentrates includes initial regrinding of concentrate in ball mill till size 60÷100% minus 0.044 mm at ratio of solid and liquid phases equal to 1:1÷2. Regrinding is being implemented during 4÷15 minutes. Then it is implemented leaching at solid phase content 9÷30 wt % in water solution of inorganic acid by concentration from 2.0÷150.0 g/dm3 at presence of ferric iron ions by concentration 3÷20 g/dm3 with usage of harmless compounds, containing active oxygen. Extraction of metals is implemented from leaching products.
EFFECT: increasing of metals extraction from concentrates, reduction of leaching time, decreasing of power consumption for leaching.
10 cl, 3 ex
SUBSTANCE: invention refers to hydrometallurgy of noble metals and can be used at processing of gold-silver alloys. The method includes dissolving of granulated gold-silver alloy with chloronitric acid and separation of silver chloride. Before sediment of gold out of the produced solution it is treated with carbamide powder, then settled during 12-24 hours and the sediment of silver chloride is repeatedly separated. The settled gold is washed with concentrated hydrochloric acid during 4-5 hours at the temperature of 50-60°, and after cooling of the washing solution, washed with water.
EFFECT: reduction of "back remaining" of gold in the process, increased output of available product, including reduction of material and labour consumption required for obtaining of final product.
1 tbl, 2 ex
SUBSTANCE: invention refers to hydro metallurgical process and can be used for extraction of non-ferrous, rare and noble metals out of sulphide minerals and concentrates. The method includes oxidation of the primary raw material in the form of pulp with use of oxidising agents, containing nitrogen oxides; it also includes regeneration of lower nitrogen oxides to higher ones by oxidation. Pulp is subject to oxidation under the condition of controlled acidity with constant neutralisation of created as the result of sulphides oxidation sulphur acid to such level of acidity when formation of elemental sulphur is eliminated; as neutralisers, natural or artificial substances are used chosen from CaCO3, MgCO3, Ca(OH)2, CaO, NaOH, CaHPO4 depending on the necessity of producing products with specified physic and chemical properties such as: filterability, condensability, insolubility of arsenic, and nontoxicity. Oxidation is carried out at mixing which facilitates an adequate mass transfer and effective behavior of chemical reactions within a temperature range of 20-90°C, predominantly in the interval of 65-85°.
EFFECT: creating conditions for most complete extraction of metals excluding formation of elemental sulphur.
9 cl, 3 dwg
FIELD: nonferrous metallurgy.
SUBSTANCE: invention relates to processing nickel-containing intermediate products, namely ferriferous cakes obtained in hydrometallurgical nickel production process. Method comprises repulping of cakes with acid solution containing alkaline metal salts at elevated temperature and maintaining pH of pulp between 1.2 and 1.6. Repulping is effected in reactor provided with mechanical stirring means at specific stirring power in first stage 500-1000 W/m3 and in second stage 5-100 W/m3.
EFFECT: enhanced removal of nickel and improved filterability of products.
8 cl, 5 tbl
FIELD: nonferrous hydrometallurgy; other industries; methods of reprocessing of materials containing nickel in its protoxide form.
SUBSTANCE: invention is pertaining to the hydrometallurgy of non-ferrous metals and may be used at development of the production processes of refining of the converter mattes and reprocessing of other material containing nickel in its protoxide form. The method includes dissolution of these products in solutions of inorganic acids at potential of no less than 1.2 V of the hydrogen electrode, for what they introduce into the initial mash the oxidant, which if necessary is used in the course of production process for maintaining of the necessary value of the redox potential. The method allows to leach the persistent mineral forms containing nickel protoxide in the atmospheric conditions with production of solutions, containing less than 10 g/dm3 of the free acid at the variable concentration of nickel. The technical result of the invention is the increased extraction of the nickel into the solution at simplification of the production method.
EFFECT: invention ensures the increased extraction of the nickel into the solution at simplification of the production method.
2 cl, 3 tbl, 4 ex
FIELD: precious metal technologies.
SUBSTANCE: invention relates to recovery of precious metals from of sulfuric acid production ash waste obtained from sulfuric pyrite firing stage. Method contemplates mixing ashes with a reagent, irradiating resulting mixture by microwave field, and separating it into non-magnetic residue and magnetic fraction. The latter is treated with acid and/or oxidant solution. Precious metals are sorbed from solution and suspension obtained by a sorbent, which is further burned off to give concentrate of precious metals containing notably Pt, Pd, Rh, Au, and Ag. Above-mentioned reagent is selected from potassium hydroxide and mixtures thereof with sodium formate or sodium carbonate, or potassium nitrate, or with oxalic acid, mixtures of oxalic acid with sodium formate, zinc powder with tin dichloride, and sodium peroxide with sodium carbonate. Sorbent is selected from 1,1-bis(perhydro-1,3,5-dithiazinin-5-yl)ethane, 1-hydroxy-2-(perhydro-1,3,5-dithiazinin-5-yl)ethane, 2-(perhydro-1,3,5-dithiazinin-5-yl)acetic acid, and polydithiopropane.
EFFECT: increased degree of Pt, Pd, and Rh recovery from ash pyrites.
6 cl, 1 tbl
FIELD: extraction of valuable metals from super-alloys by electrochemical decomposition.
SUBSTANCE: super-alloy is used as both electrodes, anode and cathode. Electrochemical decomposition is realized at changing polarity of electric current with frequency 0.005 - 5 Hz while using non-organic acid as electrolyte.
EFFECT: possibility for extracting valuable metals in industrial scale, lowered cost of simplified extraction process, effective solution of part of metals, separation of metal groups.
6 cl, 2 dwg, 1 ex
FIELD: hydrometallurgical processing of sludges, for example electrolysis sludges of copper-nickel process.
SUBSTANCE: proposed method includes treatment of sludges by oxidant in acid medium for converting silver into solution. Prior to treatment of sludges, they are reduced for converting silver and platinoids into metal powders; treatment is carried out in sulfamic acid medium. Used as oxidant is hydrogen peroxide of potassium or ammonium persulfate; treatment is accompanied by heating. Proposed method makes it possible to separate and clean silver from non-noble metals and accompanying metal of platinum group and gold due to obtaining selective solutions concentrated in silver.
EFFECT: chemically and ecologically safe technology; low cost of reagents.
2 cl, 2 tbl, 2 ex
FIELD: non-ferrous metallurgy; methods of refining gallium.
SUBSTANCE: proposed method includes treatment of gallium with acid at mixing in drum-type reactor. Treatment is carried out at temperature of 40-60°C and rotational speed of reactor of 1-20 rpm.
EFFECT: high degree of cleaning; increased good-to-bad yield; reduced losses of gallium.
1 dwg, 1 tbl, 1 ex
FIELD: chemical industry; methods of extraction of the noble metals from production of the ash-wastes of the sulfuric acid.
SUBSTANCE: the invention is pertaining to extraction of noble metals (Pt, Pd, Rh, Au and Ag) from the ash-waste of production of the sulfuric acid received at the calcination of the sulfuric pyrites. The ash-waste at first is subjected to the UHF irradiation and then it is separated into the magnetic fraction and the nonmagnetic residual. Then the nonmagnetic residual is used as the source material at treatment with the solution of the acid and-or as the oxidizing agent - at the UHF irradiation with transfer of the noble metals into the solution and suspension. The noble metals are subjected to the sorption from the solution and suspension using the sorbent, which then is burnt with production of the concentrate of the noble metals. The concentrate contains Pt, Pd, Rh, Au and Ag. The magnetic fraction contains wustite, haematite and magnetite. As the acid at the treatment use HCl, the mixture of HCl and HF, the mixture HCl and-H2SO4, the mixture of HCl and HBr, the mixture of HCl and HJ, and as the oxidizing agent useН2О2,Cl2,Br2, NaClO3, HNO3, the mixture of NaClO3 and the mixture ofNaCl03 andI2 or the mixtureofCl2 and Br2. As the sorbent use 1,2-bis-( perhydro-1,3,5- dithiazin-5-silt)ethane, 1- oxy-2-( perhydro-1,3,5- dithiazin-5-silt)ethane, 2 (perhydro-1,3,5- dithiazin-5-silt) acetic acid, polypolydithiopropane. The technical result of the invention is the increased degree of extraction of the noble metals into the concentrate.
EFFECT: the invention ensures the increased degree of extraction of the noble metals into the concentrate.
6 cl, 1 tbl, 1 ex
SUBSTANCE: invention concerns industrial sanitation and environmental protection field, at usage in manufacturing and in domestic conditions of metallic mercury, its containing devices and facilities, and also of amalgams, and is intended for neutralisation of mercury at its ingress both on surfaces of different materials and into volumes (material, brick, concrete and so forth). Neutralisation technique of metallic mercury by immobilisation includes its oxidation by means of treatment by water solution of hydrogen peroxide. At that additionally to oxidation it is implemented mercury deposition by means of simultaneous or successive treatment by water solution of reagent, transferring metallic mercury into insoluble or sparingly soluble in water compound of natural or anthropogenic composition. In the capacity of reagent there are used water-soluble compounds of alkaline or alkaline-earth metals for instance, sulphates, phosphates or carbonates.
EFFECT: effectiveness increase of process at excluding of mercury - organic compounds formation.
5 cl, 5 ex
SUBSTANCE: method includes leaching of material with water solution of chemical reagent and successive treatment of produced pulp for extraction of germanium and zinc. At that leaching is carried out with mechanical, grinding and disintegrating effect, using as solution chemical reagent of solution, containing oxidant at amount from 1.8 to 2.5 kg per 1 kg of germanium contained in source material and hydroxide of alkali metal at amount maintaining medium pH from 12 to 14 at ratio of solid and liquid phases 1:(3-8). Germanium is sorption settled out of produced pulp by means of transmission of pulp through ion exchanging resin; alkali at amount facilitating 13.5-14 pH of medium and water at amount facilitating ratio of solid and liquid phases 1:(5-8) are added to pulp. Product received after sorption sedimentation of germanium is treated in autoclave at temperature of 120-250°C and pressure of 6-40 atm. Then liquid phase is separated out of which zinc is extracted while germanium is eluated out of ion exchanging resin. Germanium is extracted out of produced eluate.
EFFECT: increased degree of germanium and zinc extraction.
4 cl, 2 ex
SUBSTANCE: invention refers to extraction and concentration of thorium out of process waste of loparit concentrates treatment - spent melt of saline sprinkler filter (SSF) of loparit concentrate chlorination process. The method includes preparation of suspension by means of discharge of spent melt of saline sprinkler filter (SSF) into water, incorporation of high molecular flocculant, of holding, filtering, separation of sediment, obtaining of chloride solution, and of treatment with steel scrap and metal magnesium. Prior to obtaining chloride solution the source suspension is heated to 60-90°C and treated with solution of sodium hydroxide to pH 1.5-2.0 and to 0.1-0.3% solution of high molecular flocculant at amount of 3-5% from the source volume of suspension; then suspension is held for 2-4 hrs. Chloride solution is received by means of filtration of spent suspension obtaining sediment of rare metals; chloride solution is then treated with steel scrap and metal magnesium; at that the solution is successively treated first with the steel scrap at amount of 3-5 mass fractions of iron per 1 fraction of iron ions (III) in chloride solution at 80-100°C for 1-3 hrs till achieving the value of pH in a pulp equal to 3.0-3.5. Then the pulp is separated from the non-reacted portion of the steel scrap and is treated with metal magnesium to pH 3.5-4.5, and further with 0.1-0.3% solution of high molecular flocculant taken at amount of 5-20% from the volume of chloride solution. Thus produced pulp is held without mixing for 1-4 hrs and filtered producing thorium containing sediment; the said sediment is washed at filter first with solution containing 1-5 g/dcm3 of sodium sulphite, then with water. Washed out sediment is repulped in solution of sodium hydroxide with concentration of 50-150g/dcm3 at a ratio of "Ж:Т"=3-5 at 60-90°C for 2-3 hrs, after what the pulp is filtered with separation of alkaline filtrate. Thorium containing sediment at the filter is washed with water, pressed at the filter and dried; the alkaline filtrate and process water are merged and mixed, then heated to 80-90°C, and treated with solution of sodium hydroxide to pH 11-13 with production of hydroxide pulp. Hydroxide pulp is filtered and then radioactive sediment is produced at the filter; it is washed out with water and transferred to a special wastes depositary, while filtrate is mixed with 10-20 volumes of shop flush water, heated to 80-90°C and again treated with solution of sodium hydroxide to pH 11-13. Obtained pulp is held and filtered thus producing sediment of rare metals and deactivated chloride solution which is discharged to drainage. Sediment of rare metals is unloaded from the filter, merged with sediment of rare metals extracted from the source suspension, dried, washed out and then transferred for preparation of charge for its further chlorination together with the loparit concentrate.
EFFECT: upgraded efficiency of thorium extraction and simultaneously solving problem of neutralisation and utilisation of process waste.
1 dwg, 1 ex
SUBSTANCE: invention refers to non-ferrous metallurgy and can be used for extraction of vanadium out of ashes which is waste produced by burning of sulphuric vanadium containing black oil in heat engines of heat and hydropower stations. The method consists in the following: source ashes are mixed with sodium carbonate and water at a weight ratio of 100:(10-60):(30-50), then produced mixture is held at temperature of 100-150°C, preferably 115-120°C, during 2 hours. Vanadium is leached out of produced self-diffusing cake with water at temperature of 95-100° and a ratio of liquid: solid = (1.5-3):1.
EFFECT: avoiding of generating harmful gas exhausts at extraction of vanadium and implementation of available equipment.
1 tbl, 2 ex
SUBSTANCE: method for pile loosening by blasting in heap leaching (HP) of ores is used to intensify the HP process due to performing drilling-and-blasting works. The method for pile loosening by blasting in heap leaching of ores, whereby a pad is formed by protective drainage 14 and damp-proof layers 15 made of polymeric film, consists in drilling boreholes 2, placing low-density explosive charges into the boreholes 2 and blasting of said charges. The boreholes 2 are drilled to the depth of the protective and drainage layer 14, charges 9 and 12 are distributedly disposed in the boreholes 2. Pieces 13 and 11 of an expanded material, e.g., foamed polystyrene, are placed respectively in the lower part of the borehole and between the charges. The charges are blasted with time delaying beginning from the top charge 9 to the bottom one 12.
EFFECT: increase in the efficiency of ore loosening; prevention of damage of the anti-seepage polymeric film membrane and of penetration of the toxic solution into ground waters.
SUBSTANCE: said utility invention relates to the field of noble metal metallurgy, in particular, to methods of recovery of osmium from non-ferrous metallurgy platinum-containing electrolytic slime processing products, namely, cakes containing selenium and non-ferrous metals. The cake is subjected to preliminary caustic treatment with caustic soda solution with a concentration of 180-220 g/dm3, and the residual matter resulting from the separation is heated at a temperature of 100 to 130°C. The heated residual matter is subjected to treatment with sulphuric acid and secondary caustic treatment. The osmium concentrate resulting from the caustic treatment is sent for the distillation of the osmium tetraoxide, with its recovery using ammonia solution and subsequent preparation of osmium salt.
EFFECT: increase in efficiency and maximum simplification of osmium recovery process.
4 cl, 3 dwg, 1 tbl, 11 ex
FIELD: hydrometallurgy and mining industry; ecological methods of extraction of metals.
SUBSTANCE: proposed method of extraction of metals from solid metal-containing materials or ores includes treatment or underground leaching-out with solution of reagent obtained by electrolysis treatment of solution containing halogenide-anion and separation of metal from this solution. Electrolysis treatment is carried out under condition of positive mass transfer on revolving electrode or on electrode moving at acceleration of no less than 0.1 m/s. After electrolysis treatment, water-soluble polymer used as surfactant is introduced into reagent solution in the amount of no less than 0.01%.
EFFECT: enhanced efficiency and ecological safety due to reduced power requirements, intensification of process, avoidance of toxic emissions and use of safe chemicals.
7 cl, 2 dwg, 6 ex
FIELD: hydrometallurgy of extraction of non-ferrous, rare-earth and noble metals from rebellious raw materials containing natural carbon or other rebellious compounds.
SUBSTANCE: proposed method includes treatment of rebellious carbon-containing mineral raw material by oxygen-containing oxidant followed by extraction of noble metal compounds from liquid phase. Treatment of carbon-containing mineral raw material by oxygen-containing oxidant is carried out in presence of reductants possessing donor-acceptor properties which are expressed in the fact that at first stage of chemical reactions, reductants give off their electrons to oxygen-containing oxidant, forming stronger oxidant as compared with first one in form of short-lived radicals and intermediate products of oxidation of donor-acceptor reductants which are also used as oxidants.
EFFECT: increased extraction of non-ferrous, rare-earth and noble metals; low cost of process.
FIELD: non-ferrous metallurgy; pressure hydrometallurgy and processing of oxidized silicate nickel ores enriched with magnesium.
SUBSTANCE: proposed method includes sulfidizing stage and oxidizing stage with the use of elemental sulfur at the sulfidizing stage in form of aqueous suspension and oxygen at the oxidizing stage. At the sulfidizing stage, use is made of solution of sulfates with bivalent cation and surfactant which facilitates hydrophilization of elemental sulfur; surfactant is fed to suspension at grinding the sulfur which makes it possible to perform both stages of pressure leaching at temperature below 200°C and total pressure in autoclave below 2.0 Mpa, thus ensuring high extraction of nickel into solution up to 93-97%.
EFFECT: considerable reduction of pressure leaching temperature and total pressure in autoclave at high extraction of nickel into solution.
2 cl, 4 ex
FIELD: leaching extraction of non-ferrous and precious metals from refractory ores by cyaniding process.
SUBSTANCE: method involves cyclical or continuous leaching of metal from ore-containing pulp; supersonic processing; collecting and processing pregnant solution; providing supersonic processing at cyclical leaching after first leaching process and at continuous leaching - before first leaching process by exposing to supersonic field having intensity of 1-70x104 W/m2 in hydrodynamic generator and simultaneously feeding air. Method allows efficiency of metal extraction process to be increased due to fundamental changing of supersonic process parameters, in particular, supersonic field intensity, increased concentration of solved and dispersed gaseous oxygen and products of acoustic-chemical reactions in pulp, and additional grinding of ore grain.
EFFECT: increased efficiency of process and reduced labor intensity due to the fact that generator functions in self-oscillating operational mode and does not need additional works, and simplified process.
SUBSTANCE: method to isolate silica from hydrothermal medium implies DC current treatment of thermal medium in electrodialysis apparatus with an anode, a cathode and a porous membrane, anodic current density being 10-40 А/m2.
EFFECT: increase in efficiency and degree of recovery of silica from hydrothermal fluids.
3 tbl, 1 dwg, 4 ex