Method of phosphogypsum processing for manufacture of concentrate of rare-earth elements and gypsum |
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IPC classes for russian patent Method of phosphogypsum processing for manufacture of concentrate of rare-earth elements and gypsum (RU 2458999):
Method of processing phosphogypsum with extraction of rare-earth elements and phosphorus / 2457267
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.
 Extraction method of amount of rare-earth elements from solutions / 2457266
Extraction method of rare-earth elements from solutions containing multiple excess iron (III) and aluminium, with pH=0.5÷2.5 involves sorption using macroporous sulfocationite as sorbent. At that, as sorbent there used is macroporous sulfocationite containing more than 12 to 20% of divinyl benzene.
 Method of extracting cerium from salt solutions / 2456359
Method of extracting cerium cations from aqueous solutions of its salts involves use of a sodium dodecyl sulphate surfactant collector with concentration corresponding to the reaction stoichiometry: Ce+3+3DS-=Ce[DS-]3, where Ce+3 is a cerium cation, DS- is a dodecyl sulphate ion. Cerium cations are extracted via flotoextraction in an organic phase at pH=7.6-8.3. The organic phase used is isooctyl alcohol.
Method of processing of phospho-gypsum / 2456358
Method of processing of phospho-gypsum involves processing with an aqueous solution containing alkali metal carbonate, heating followed by separation of calcium carbonates and strontium. Before treatment phospho-gypsum is bioleached using bacterial complexes consists of several kinds of acidophilic thion bacteria in an active growth phase and adapted to phospho-gypsum. Bioleaching is carried out in a vat mode when a ratio of S:L = 1:5-1:9, temperature is 15-45°C and aeration is for 3-30 days with transfer of rare earth elements and phosphorus to the liquid phase. The resulting cake is treated with an aqueous solution containing potassium carbonate as an alkali metal carbonate.
Method for extracting scandium from pyroxenite raw material / 2448176
Method involves opening of raw material and leaching of scandium with further separation of solid and liquid phases. As initial raw material there used is scandium-containing pyroxenite refuse ore with fineness of less than 1 mm. Opening of raw material and leaching of scandium is performed using biocomplex of iron oxidating acidophilic thionic bacteria Acidithiobacillus thiooxidahs, Acidithiobacillus ferrooxidans, Leptospirillum ferrooxidans extracted and grown from natural strains of microorganisms incidental to the used initial raw material and adapted with cultures from museum collection, with bacteria population of 107 cells/ml at S:L=1:5-1:7, temperature of 15-45°C, initial Eh 650 mV, pH 1.5-2.15, Fe3+ concentration of 13-17 g/l, Fe2+ - 1.5-3 g/l and at atmospheric pressure. After separation of solid and liquid phases the latter is supplied for obtaining scandium fluoride.
 Method of extracting rare-earth metals yttrium (iii), cerium (iii) and erbium (iii) from water solutions / 2441087
Proposed method comprises contact of extragent containing rapic acid and inert latent solvent with water solution, mixing obtained mix, settling and phase separation. Kerosene is used as said inert latent solvent. Extraction is performed for 10-15 min in two steps at pH=4.5-5.5 and extragent-to-water solution ratio of 1:10. In first step, extraction is carried out at content of rapic acid in extragent of 5-7 vol. % with separation of cerium (III) and mix of yttrium (III) and erbium (III). In second step, extraction is carried out at content of rapic acid in extragent of 15-17 vol. % with separation of yttrium (III) and erbium (III).
 Method of extracting ions of erbium from water solutions using sodium dodecyl sulphate / 2440853
Invention relates to production of pure rare-earth metals or their oxides from low-grade or technogenic stock by ion flotation. Said ion flotation comprises using sodium dodecyl sulphate as a collector in concentration corresponding to stoichiometric reaction: Me+3+3DS-=Me[DS-]3, where Me+3 is metal cation, DS- is dodecyl sulphate-ion. Erbium salts are used as extracted ions. Note here that maximum yield of erbium is reached at pH=6.4.
 Procedure for processing grinding wastes from manufacture of permanent magnets / 2431691
Invention refers to procedure of extraction of rare earth elements (REE) from grinding wastes of manufacture of permanent magnets. The procedure consists in dissolving grinding wastes in sulphuric acid, in extraction of double salts and sodium REE-Na by sedimentation and in washing double salts. Further, double salts are conversed in hydroxide of REE and hydroxides of REE are washed. Upon washing hydroxides of REE are oxalate conversed, dried and burned producing sum of REE oxides. After sedimentation of double salts of rare earth elements and sodium REE-Na mother solutions are processed producing ferriferous and cobalt cakes.
 Method of cleaning fluorine-containing rare-earth concentrate / 2429199
Concentrate obtained when processing apatite is treated with concentrated sulphuric acid in the presence of hydrated silica at 95-130°C with transition of fluorine to gaseous phase and obtaining a sulphate-phosphate rare-earth concentrate which is leached with water to obtain a sulphate rare-earth concentrate free from fluorine and phosphorus and a sulphate-phosphate solution.
 Procedure for separation of actinoide from lanthanide in water medium by complexation and membrane filtration / 2427658
Procedure consists in stage of introduction of complex forming compound to contact with water medium containing said actinoid and one or more lanthanides. Also, the said complex forming compound in not complexated state is not retained with the said membrane and is capable to form complex with said actinoid containing the said element and at least two molecules of the said complex forming compound, also, complex is capable to be retained with the membrane. Further, there is performed the stage of water medium passing through the membrane for formation of filtrate containing water effluent depleted with said actinoid from one side, and retentate containing the said complex.
 Multicolumn sequential extraction of ionic metal derivative / 2458725
Invention may be used in hydrometallurgy. Proposed invention allows separating such metals as uranium, nickel, copper and cobalt present in liquid wastes of ore leaching. Solution containing metal ions is forced through stationary layer of resin, Particularly, through, at least, three zones. Note here that solution drive appliances are arranged between adjacent zones and between last and first zones. Proposed method comprises several sequences, each comprising, at least, one step selected from steps of adsorption, washing and desorption. Every next sequence is performed by shifting fronts into zones downstream of circuit with identical increment unless cyclic shift of inlet and discharge points.
 Method of ion-exchange uranium extraction from sulfuric solutions and pulps / 2458164
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.
Method of gold extraction from mercury-containing cyanic solutions / 2458160
Method of gold extraction from mercury-containing cyanic solutions consists in sorption by ion-exchange resin of AM-2B mark. Then mercury de-sorption is carried out from saturated ion-exchange resin at a temperature 40-50°C and for 6 hours and aurum de-sorption. Note that mercury de-sorption is done by solution containing sulfuric acid 30-50 g/l with the presence of hydrogen peroxide 5-10 g/l.
Extraction method of amount of rare-earth elements from solutions / 2457266
Extraction method of rare-earth elements from solutions containing multiple excess iron (III) and aluminium, with pH=0.5÷2.5 involves sorption using macroporous sulfocationite as sorbent. At that, as sorbent there used is macroporous sulfocationite containing more than 12 to 20% of divinyl benzene.
 Method for extracting metals from depulped ores / 2454470
Method for extracting metals from depulped ores involves crushing, ore depulping in leached solution and sorption of metal. Leaching is performed in ultrasound pulp cavitation mode. Metal sorption on ion-exchange resin is performed from pulp filtration solution in intensity field of alternating current in sorption activation mode of extracted metal and suppression of sorption of impurities. At that, polarity of electrodes is constantly changed to avoid deposition of metal on cathode. Leaching and sorption of metal is performed in a unit providing solution circulation till the specified completeness of leaching from ore and its complete sorption on ion-exchange resin is achieved.
Method for sorption extraction of iron from nitrate salt solutions / 2453368
Invention relates to ion exchange and can be used for sorption extraction of iron from salt solutions formed when processing aluminium-containing material using acid techniques. Extraction of iron to residual content of Fe2O3 in the purified solution of not more than 0.001% is carried out through sorption of iron with a cationite in H-form, containing aminodiacetic functional groups. The iron sorption and desorption steps are alternated without intermediate washing of the cationite. Iron is desorbed in counterflow conditions with nitric acid solution.
 Method for extraction of palladium (ii) from wasted catalysts / 2442833
The invention relates to hydrometallurgy of precious metals and can be used to extract palladium from wasted catalysts, including catalysts of low-temperature oxidation of carbon oxide (II) based on γ-Al2O3, containing palladium chloride (II) and cupric bromide (II). The method includes acid leaching of palladium from wasted catalysts from the chloride solution. Furthermore, the acid leaching is carried out by 1 M solution of hydrochloric acid. The resulting solution is diluted with water to pH 1. The sorption of palladium is carried out from the diluted solution using chemically modified silica containing grafted groups of γ-aminopropyltriethoxysilane.
Extraction of gold, palladium and platinum from chloride solution / 2441929
invention refers to the area of the extraction of gold, palladium and platinum from hydrochloric solutions. The method comprises their anionite sorption and desorption. The sorption shall be performed with low-basic anionites. After sorption, desorption with a mixture of sodium sulfite salts mixture Na2SO3 and sodium nitrite NaNo2.
 Method of separating platinum (ii, iv) and rhodium (iii) in aqueous chloride solutions / 2439175
Method involves sorption of platinum (II, IV) and rhodium (III) through contact of the solution with a strongly basic anionite and then desorption from the anionite. Sorption is carried out from freshly prepared and held solutions on a Purolite A-500 anionite, containing a quaternary ammonium base as a functional group. Desorption from the anionite is carried out in two steps: at the first step - 24 hours after contact with 2M NH4SCN solution or 2M KNO3 solution to extract platinum. At the second step - after a further 24 hours with 2M HCl solution or 1M thiourea solution in 2M H2SO4 solution to extract rhodium.
 Procedure for processing vanadium containing raw material / 2437946
Procedure consists in preparation of water pulp from raw material, in introduction of sulphuric acid and anionite into it for leaching and in extraction of vanadium from pulp by sorption. Upon sorption saturated anionite is withdrawn and washed; vanadium is de-sorbed from anionite and regenerated anionite is introduced to the stage of leaching and sorption. Also, water vanadium pulp is prepared from vanadium containing raw material. As such there is used oxidised slag or slime at pH 11.5-7.5. Sulphuric acid is introduced into prepared water pulp at S:L=1:2 to pH 4.5-4.0. Vanadium is extracted from pulp by counter-flow sorption at pH 4.5-1.8 with following saturated ionite washing at drainage. Value of pH in pulp is maintained at 4.5-4.0 at withdrawal of saturated anionite, while at introduction of regenerated anionite - 2.0-1.8.
 Method of producing vanadium oxide / 2454369
Invention relates to vanadium oxide extraction. The method of producing vanadium oxide involves preparation of starting vanadium-containing material for burning, burning with lime treatment, leaching with sulphuric acid, separating the solid substance and liquid, precipitation of ammonium polyvanadate with an ammonium salt and removing ammonia by calcination or reduction to obtain vanadium oxide. The solid starting material used at said steps has total amount of alkali metal of not more than 0.3 wt % and total amount of Cl- and NO3 - ions of not more than 0.1 wt %, and the liquid starting material has total amount of alkali metal of not more than 0.1 g/l and total amount of of Cl- and NO3 - ions of not more than 0.1 g/l.
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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
The invention relates to the technology of complex processing of phosphogypsum produced in sulfuric acid production of mineral fertilizers from phosphate rock, and can be used to concentrate production of rare earth elements and gypsum building materials and cement. When sulfuric acid processing of Apatite concentrate on mineral fertilizers produced waste phosphogypsum, which gets a significant amount of REE. Known methods of processing of phosphogypsum are not effective enough. The main reasons for this is the inability of phosphogypsum processing (postopera and fotodigital with getting rich REE concentrates suitable for further processing. The competitiveness reserve phosphogypsum may be the development of more universal technology of its processing that obtains a plaster, suitable for the production of gypsum building materials and cement, the increase in the content of REE in the resulting concentrate and increase the extraction of lanthanides average (samarium, europium, gadolinium, terbium, dysprosium and yttrium (yttrium, holmium, erbium, ytterbium) groups. The known method of phosphogypsum processing for the production of REE concentrate and gypsum (see Ciurla Z., Grudzewski W. Ekonomiczne problemy odzyskiwania ziem rzadkich z fosfogipsów. I. Utylizacia fosfbipsów z odzyskiwaniem lantanowców. // Gosp. surow. miner. 1990. V.6, №4. S-828), including the leaching of phosphogypsum 10 wt.% H2SO4for 1 hour at 60°C and the ratio of T:W=1:2,5 translation of phosphorus and REE in the leaching solution and obtaining a precipitate of gypsum, sludge separation of gypsum from the leaching solution, washing of the gypsum from the rest of the leaching solution by repulpable in water, separation of REE concentrate from the leaching solution by ammonization of leaching solution to provide a pH of 8-9 with precipitation of hydroxides REE and separating the precipitate of the hydroxides of the REE from the mother liquor. To be utilized dilute solution of ammonium sulfate evaporated. The degree of extraction of REE in the leaching solution is not more than 45%. The disadvantages of this method include that it is characterized by a relatively low degree of REE extraction in the leaching solution and correspondingly low content of REE in hydroxide concentrate. Sulfuric acid leaching solution is neutralized with ammonia, which leads to a high consumption of sulfuric acid and ammonia. In addition, the necessity of heating used for leaching sulfuric acid solution to 60°C and evaporation of the resulting dilute solution of ammonium sulfate lead to large energy costs. Known also adopted as about what atipa way of phosphogypsum processing for the production of REE concentrate and gypsum (see Pat. 2337879 of the Russian Federation, IPC C01F 11/46 (2006.01), 2008), including the leaching of phosphogypsum 22-30 wt.% a solution of sulfuric acid for 20-25 minutes with the transfer of phosphorus and REE in supersaturated by REE solution leaching and obtaining a precipitate of gypsum, which is separated from the leaching solution by centrifugation to provide a residual moisture content of the residue is not more than 20%. Recovery of REE in the leaching solution is 64,6-82,1%. From the leaching solution by crystallization allocate the REE concentrate and separate it from the mother liquor. The resulting concentrate is based on the double sulphates REE and sodium contains up to 29.4% ΣTr2O3. The precipitated gypsum is treated with a basic calcium compound (slaked or unslaked lime or limestone) to a pH of more than 5. Uterine sulfate solution control on the content of impurity is phosphorus, is subjected, if necessary, cleaned and sent to the leaching of phosphogypsum. The disadvantages of this method are relatively low REE content in the resulting concentrate, and lack of average recovery of REE and yttrium groups. In addition, leaching of phosphogypsum used sulfuric acid solution of high concentration (22-30 wt.%), that requires greater consumption of basic compounds of calcium in the gypsum sludge treatment to a pH of more than 5 and the use of complex equipment (centrifuges) to ensure the ecene a residual moisture content of gypsum is not more than 20%. The present invention is directed to the achievement of the technical result consists in increasing the efficiency of processing of phosphogypsum by increasing the content of REE in the resulting hydroxide and carbonate concentrates and increase of REE extraction medium and yttrium groups, as well as by reducing the neutralizing calcium. The technical result is achieved in that in the method of phosphogypsum processing for concentrate production of rare earth elements (REE) and gypsum, including the leaching of phosphogypsum with a solution of sulfuric acid with the transfer of phosphorus and REE in solution and obtaining a precipitate gypsum, recovery of REE from the solution and neutralization precipitate gypsum basic calcium compound, according to the invention, the leaching is carried out with a solution of sulfuric acid with a concentration of 1-5 wt.%, recovery of REE from solution leaching carried out by sorption using sulfonic cation exchanger in the hydrogen or ammonium form, with subsequent desorption of the REE solution of ammonium sulfate and introduction to the received desorbed ammonia or ammonium carbonate deposition and separation of the hydroxide or carbonate of REE concentrate. The achievement of the technical result contributes to the fact that leaching of phosphogypsum carried out by passing a solution of sulfuric acid through the layer of phosphogypsum is about a rate of 0.5-1.25 m 31 m2a day or by agitation leaching. The achievement of the technical result also contributes to the fact that for desorption REE use of ammonium sulfate solution with a concentration of 200-300 g/l The achievement of the technical result is also that ammonia or ammonium carbonate is introduced into desorbed to provide a pH of at least 7. The essential features of the claimed invention, determining the amount of the requested legal protection and sufficient to obtain the above-mentioned technical result relate to the technical result is as follows. The use of leaching solution of sulfuric acid with a concentration of 1-5 wt.% provides the necessary degree of leaching of REE and phosphorus from phosphogypsum with obtaining solutions which can effectively adsorb REE-sulfonic cation exchanger. The decrease in the concentration of sulfuric acid is less than 1 wt.% reduces the recovery of REE in the leaching solution and allows you to get purified gypsum content of P2O5not more than 0.5-0.6 wt.%, that is a necessary condition for its use in the production of gypsum building materials and cement. Increasing the concentration of sulfuric acid above 5 wt.%, without impacting significantly on the increase of REE extraction, particularly in the middle and yttrium groups, and phosphorus from phosphogypsum in races is a thief leaching, complicates the sorption of REE-sulfonic cation exchanger and increases the consumption of basic calcium compounds to neutralize sulfuric acid to precipitate gypsum. The use of sulfonic cation exchanger in the hydrogen or ammonium form, containing functional group SO2H or SO3NH4provides almost complete sorption of REE from sulfuric acid leaching solution with simultaneous separation of a significant portion of the phosphorus, fluorine and other cationic impurities. Use for desorption REE solution of ammonium sulfate provides a high degree of extraction in desorbed amount REE, including average REE and yttrium groups. Introduction to desorbed ammonia or ammonium carbonate provides getting rich hydroxide and carbonate concentrates suitable for further processing on individual REE with simultaneous separation of a significant portion of the cations of calcium. The resulting solution of ammonium sulfate can be used in circulation. The combination of the above features is necessary and sufficient to achieve the technical result of the invention to increase the content of REE in the resulting hydroxide and carbonate concentrates and the increase of REE extraction medium and yttrium groups, as well as in the reduction of neutralizing calcium. All this paragraph is increases the efficiency of phosphogypsum processing. In some cases, of the preferred embodiment of the invention the following specific operations and operational parameters. Leaching of phosphogypsum by passing a sulfuric acid solution through a fixed bed of phosphogypsum at a rate of 0.5-1.25 m31 m2the day provides an effective leaching is isomorphic decrystallizing REE and phosphorus from fotodigital without the use of mixing pulp, which reduces the energy consumption by sulfuric acid leaching. In addition, this approach can be applied for the organization of geotechnical processing of phosphogypsum dumps. Acid treatment of phosphogypsum by agitation leaching preferred for processing fresh phosphogypsum formed when sulfuric acid processing of Apatite concentrate on mineral fertilizers. Use for desorption REE of ammonium sulfate with a concentration of 200-300 g/l due to the fact that at this concentration of ammonium sulfate solubility REE maximum. This facilitates desorption by reducing the volume of solution used. At least 200 g/l and most 300 g/l of the ammonium sulfate concentration decreases the solubility of REE, which is undesirable. The introduction of ammonia or ammonium carbonate in desorbed to pH not less than 7 provides almost complete precipitation of REE with about the education of ammonium sulfate. The above private features of the invention allow a method to optimally from the point of view of increasing REE content in the resulting hydroxide and carbonate concentrates and increase of REE extraction medium and yttrium groups. Example 1. 3.35 kg phosphogypsum load in a polyethylene column internal diameter 36 mm, Height of the layer of phosphogypsum 1.5 m, composition, wt.%: CaSO4·2H2O - base, P2O5- 1,05, the sum of the REE oxides (ΣTr2O3) - 0,432, Na of 0.24. Conduct leaching of phosphogypsum 6.7 l sulfuric acid solution with a concentration of 4 wt.% within 4 days. The leaching is carried out by passing the solution of sulphuric acid by gravity through the layer of phosphogypsum with a speed of 1.25 m31 m2a day in the leaching solution separated from the precipitate gypsum spontaneously. Get 5,07 liter of leaching solution with concentration, g/l: P2O3- 4,8, ΣTr2O3- 1,649, Na2O - 2,5 and 3.33 kg sludge gypsum with residual moisture 48,9%. Recovery of REE in the leaching solution was 53,54%. The precipitated gypsum is neutralized to pH 7 by adding 37,2 g (11.1 g per 1 kg of phosphogypsum) basic compound of calcium in the form of quicklime. Get in terms of air-dry the product 3,444 kg gypsum content, wt.%: P2O5- 0.32 and F - 0,045. Low content of phosphorus and fluorine in plaster of 0.41 wt.% P 2O5and 0.06 wt.% F in terms of CaSO4the permissible content of each is not more than 0.5 wt.%) allows you to successfully use gypsum for the production of building materials and cement. The leaching solution is passed at a rate of 2.4 cm/min through a plastic column with an inner diameter of 36 mm, filled to a height of 600 mm sulfonic cation exchanger KU-2-8 emergencies in hydrogen H+the form, with the formation of sulfuric acid solution containing 4.8 g/l P2O5. The degree of sorption of REE from solution was 99.6% and almost the same for all REE. Then carry out desorption of the REE from the saturated sulfonic cation exchanger by treatment with 2 l of a solution of ammonium sulfate (NH4)2SO4concentration of 300 g/L. the Degree of desorption ΣTr2O3was 85.2%, the degree of desorption of individual REE are shown in Table 1.
Received in 2 l desorbed enter the ammonium carbonate to provide a pH of 7 with precipitation and separation of carbonate REE concentrate. Recovery of REE from decorate in carbonate concentrate containing, calculated on the amount of anhydrous oxides of at least 90 wt.% ΣTr2O3that was 99.2%. Extracting rare earth elements from phosphogypsum in carbonate concentrate is 48.7 percent, while the average recovery of REE and yttrium groups was 41 and 28%. Example 2. 3.64 kg phosphogypsum load in a polyethylene column internal diameter 36 mm, Height of the layer of phosphogypsum 1,62 is, composition, wt.%: CaSO4·2H2O - base, P2O5- 0,87, ΣTr2O3- 0,412, Na of 0.24. Conduct leaching of phosphogypsum 7,28 l sulfuric acid solution with a concentration of 1 wt.% within 10 days. The leaching is carried out by passing the solution of sulphuric acid by gravity through the layer of phosphogypsum with a speed of 0.5 m31 m2a day in the leaching solution separated from the precipitate gypsum spontaneously. Get 5,72 liter of leaching solution with concentration, g/l: P2O3- 3,13, ΣTr2O3- 1,56, Na2O - 2,3 and 3,624 kg sludge gypsum with a residual moisture content of 43.1%. Recovery of REE in the leaching solution was 59.5%. The precipitate gypsum neutralized to pH 6.5 by the addition of 8.9 g (4.4 g per 1 kg of phosphogypsum) basic compound of calcium in the form of quicklime. Receive 3.64 kg of gypsum content in terms of air-dry the product, wt.%: P2O3is 0.38, F - not found. Low phosphorus content in the gypsum (0.48 wt.% P2O5in terms of CaSO4the permissible content of not more than 0.5 wt.%) and the absence of fluorine can be successfully used gypsum for the production of building materials and cement. The leaching solution is passed at a rate of 2.4 cm/min through a plastic column with an inner diameter of 36 mm, filled to a height of 600 mm sulfonic cation exchanger KU-2-8 emergency in ammonium H 4+the form, with the formation of sulfuric acid solution containing 3.13 g/l P2O5. The degree of sorption amounts of REE from solution was 98.4%, with the degree of sorption of yttrium, average REE and yttrium groups was not less than 99%. Then carry out desorption of the REE from the saturated sulfonic cation exchanger by processing it in 3.5 l of a solution of ammonium sulfate (NH4)2SO4a concentration of 200 g/L. the Degree of desorption ΣTr2O3amounted to 93.3%, the degree of desorption of individual REE are shown in Table 2.
Received in the amount of 3.5 l desorbed injected ammonia to provide a pH of 7.2 with precipitation and separation hydroxide REE concentrate. Recovery of REE from decorate in hydroxide concentrate, containing, calculated on the amount of anhydrous oxides of at least 90 wt.% ΣTr2O3was 99.5%. Extracting rare earth elements from phosphogypsum hydroxide concentrate is 54.7 per cent, while the average recovery of REE and yttrium groups amounted to 48.6 and 31.3%. Example 3. 3.7 kg of phosphogypsum load in a polyethylene column internal diameter 36 mm, Height of the layer of phosphogypsum 1,58 m, composition, wt.%: CaSO4·2H2O - base, P2O5- 0,84, ΣTr2O3- 0,57, Na of 0.25. Conduct leaching of phosphogypsum 14,1 l sulfuric acid solution with a concentration of 5 wt.% within 10 days. The leaching is carried out by passing the solution of sulphuric acid by gravity through the fixed layer Fosfor the dog with a speed of 1 m 31 m2a day in the leaching solution separated from the precipitate gypsum spontaneously. Get a 12.5 liter of leaching solution with concentration, g/l: P2O5- 2,04, ΣTr2O3- 1,18, Na2O - 1,14 and 3,665 kg sludge gypsum with residual moisture 43,6%. Recovery of REE in the leaching solution was 64.6%. The precipitate gypsum neutralized to pH 5.5 by adding 59 g (15.9 g per 1 kg of phosphogypsum) basic compound of calcium in the form of slaked lime. Get 3,81 kg gypsum content in terms of air-dry the product, wt.%: P2O5to 0.15, F - not found. Low phosphorus content in the gypsum (to 0.19 wt.% P2O5in terms of CaSO4the permissible content of not more than 0.5 wt.%) and the absence of fluorine can be successfully used gypsum for the production of building materials and cement. The leaching solution is passed at a rate of 2.4 cm/min through a plastic column with an inner diameter of 36 mm, filled to a height of 600 mm sulfonic cation exchanger KU-2-8 emergencies in hydrogen H+form, with the formation of sulfuric acid solution containing 2,04 g/l P2O5. The degree of sorption amounts of REE from the solution amounted to 96.9%, the degree of sorption of yttrium, average REE and yttrium groups was not less than 99%. Then carry out desorption of the REE from the saturated sulfonic cation exchanger by processing its 3.5 l p is the target of ammonium sulfate (NH 4)2SO4a concentration of 250 g/L. the Degree of desorption ΣTr2O3amounted to 94.4%, degree of desorption of individual REE are shown in Table 3.
Received in the amount of 3.5 l desorbed injected ammonia to provide a pH of 7.4 with precipitation and separation hydroxide REE concentrate. Recovery of REE from decorate in hydroxide concentrate, containing, calculated on the amount of anhydrous oxides of at least 90 wt.% ΣTr2O3that was 99.6%. Extracting rare earth elements from phosphogypsum hydroxide concentrate equal to 58.8%, while the average recovery of REE and yttrium groups was 67 and 51.4%. Example 4. 1 kg of phosphogypsum containing CaSO4·2H2O - base, P2O5- 0.84 wt.%, ΣTr2O3- 0,57 wt.%, Na 0.25 wt.%, and 2 l of sulfuric acid solution with a concentration of 3 wt.% loaded into a reactor with a stirrer, conduct leaching of phosphogypsum for 1 hour with the transfer of phosphorus and REE in the leaching solution and obtaining a precipitate gypsum. The leaching solution separated from the precipitate gypsum vacuum filtration. Get 1,65 l solution leaching concentration, g/l: P2O5- 3,45, ΣTr2O3- 1,80, Na2O -1,51 and 0,996 kg sludge gypsum with a residual humidity of 35%. Recovery of REE into solution leaching amounted to 63.2%. The precipitate gypsum neutralized to pH 7.5 by addition of 10.8 g (10.8 g per 1 kg of phosphogypsum) basic compound of calcium in the form of limestone. Get 1,03 kg Gipsy content in terms of air-dry the product, wt.%: P2O5is 0.27, F - not found. Low phosphorus content in the gypsum (0,34 wt.% P2About5in terms of CaSO4the permissible content of not more than 0.5 wt.%) and the absence of fluorine can be successfully used gypsum for the production of building materials and cement. The leaching solution is passed at a rate of 2.4 cm/min through a plastic column with an inner diameter of 36 mm, filled to a height of 600 mm sulfonic cation exchanger KU-2-8 emergencies in hydrogen H+form, with the formation of sulfuric acid solution containing of 3.45 g/l P2O5. The degree of sorption amounts of REE from the solution amounted to 96.5%, and the degree of sorption of yttrium, average REE and yttrium groups was not less than 99%. Then carry out desorption of the REE from the saturated sulfonic cation exchanger by treatment of 3 l of a solution of ammonium sulfate (NH4)2SO4with a concentration of 300 g/L. the Degree of desorption ΣTr2O3accounted for 93.4%, the degree of desorption of individual REE are given in Table 4.
Received in the amount of 3 l desorbed enter the ammonium carbonate to provide a pH of 7.3 with precipitation and separation of carbonate REE concentrate. Recovery of REE from decorate in carbonate concentrate containing, calculated on the amount of anhydrous oxides of at least 90 wt.% ΣTr2O3that was 99.4%. Extracting rare earth elements from phosphogypsum in carbonate concentrate is 56.6 per cent, while the average recovery of REE and yttrium g is PP stood at 64.5 and 49.5%. Example 5 (the prototype). 200 g of phosphogypsum containing CaSO4·2H2O - base, P2O5- of 1.29 wt.%, ΣTr2O3- of 0.51 wt.% and Na of 0.05 wt.%, and 400 ml H2SO4with a concentration of 26 wt.% loaded into a reactor with a stirrer and conduct the leaching of phosphogypsum for 20 minutes at T:W=1:2 with the transfer of phosphorus and REE in the leaching solution and obtaining a precipitate gypsum. The residue is separated from the leaching solution by centrifugation. Get 364 ml of sulfuric acid solution with concentration, g/l: P2O5- 5,02, ΣTr2O3- 1,89, Na2O - 1 and precipitate gypsum with a residual moisture content of 18%. Recovery of REE into solution leaching amounted to 74.1%. The precipitate gypsum neutralized to pH 8.5 by adding 10 g of limestone (50 g per 1 kg of phosphogypsum). Obtain 210 g of gypsum with the content of P2O5to 0.29 wt.% in terms of air-dry the product. Sulfuric acid solution was incubated for 2 hours with the crystallization of REE. The sediment REE filtered. The mass of air-dried concentrate REE - 2,4, After extracting REE receive 363 ml uterine sulfate solution with a residual content of REE - 0.14 g/l and impurities of phosphorus - 5,02 g/l when the concentration of free sulfuric acid and 24.5 wt.%. The obtained mother liquor is directed to the leaching of phosphogypsum. The chemical composition of REE concentrate, wt.%: ΣTr2O342-- 54,4; CaO To 8.0; P2O5to 0.3; Fe2O3- 0,37; Al2O3- 0.08 and SiO2of 0.47. The degree of extraction of rare earth elements in the concentrate was 68.5%, including removing the average REE and yttrium groups was 20.2 and 6.3%. The given Examples show that the inventive method allows to efficiently convert phosphogypsum to receive plaster with a low content of harmful impurities of phosphorus and fluorine, which allows its use for manufacture of building materials and cement, as well as to obtain high quality hydroxide or carbonate REE concentrate containing more than 90% ΣTr2O3. The average recovery of REE and yttrium groups in concentrates amounted to, respectively, 41-67% and 28-51,4%, whereas the prototype receive concentrates on the basis of double sulphates REE and sodium containing up to 29.4% ΣTr2O3that goes only 20.2% of REE average and 6.3% REE, yttrium groups. Specific neutralizing calcium per 1 kg of phosphogypsum decreased in the case of the use of limestone 4.6-4.9 times, quicklime - 1.6 times, slaked lime - 2.2 times. 1. The method of phosphogypsum processing for concentrate production of rare earth elements (REE) and gypsum, including the leaching of phosphogypsum with a solution of sulfuric acid with the transfer of phosphorus and REE p is the target and obtaining a precipitate of gypsum, recovery of REE from the solution and neutralization precipitate gypsum basic calcium compound, characterized in that the leaching is carried out with a solution of sulfuric acid with a concentration of 1-5 wt.%, recovery of REE from solution leaching carried out by sorption using sulfonic cation exchanger in the hydrogen or ammonium form, with subsequent desorption of the REE solution of ammonium sulfate and introduction to the received desorbed ammonia or ammonium carbonate deposition and separation of the hydroxide or carbonate of REE concentrate. 2. The method according to claim 1, characterized in that the leaching of phosphogypsum carried out by passing a solution of sulfuric acid through the layer of phosphogypsum at a rate of 0.5-1.25 m31 m2a day or by agitation leaching. 3. The method according to claim 1, characterized in that for desorption REE use of ammonium sulfate solution with a concentration of 200-300 g/l 4. The method according to claim 1, characterized in that ammonia or ammonium carbonate is introduced into desorbed to provide a pH of at least 7.
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