CN108330298B - Method for extracting rubidium, cesium, lithium and potassium from polymetallic mica ore - Google Patents

Abstract

The invention discloses a method for extracting rubidium, cesium, lithium and potassium from polymetallic mica ore, which comprises the following steps: s1, uniformly mixing the polymetallic mica ore and more than two of sodium salt, potassium salt or calcium salt serving as a roasting additive, roasting, and crushing to obtain roasted sand; s2, adding water into the calcine for leaching to obtain a leaching solution; s3, removing impurities from the leachate, concentrating and salting out to obtain Na₂SO₄、K₂SO₄Mixing salt and a purifying solution; s4, adding Na into the purified liquid₂CO₃Then filtering, washing and drying to obtain Li₂CO₃And contain Rb⁺And Cs⁺The solution of (1). The method is environment-friendly and realizes the comprehensive utilization of multi-metal mica ore resources.

Description

Method for extracting rubidium, cesium, lithium and potassium from polymetallic mica ore

Technical Field

The invention relates to the field of mineral processing, in particular to a method for extracting rubidium, cesium, lithium and potassium from polymetallic mica ore.

Background

Rubidium and cesium are typical rare dispersion elements and have unique properties. Cesium and rubidium have few independent deposits, usually associated with polymetallic mica ores, and are difficult to separate. Lithium is an important metal element and has wide application in the fields of energy, chemical engineering, electronics, medicine and the like. The potassium sulfate is an excellent potassium fertilizer, is particularly suitable for crops with chlorine-repellent property, and needs to be imported by about 50 ten thousand tons each year in China. Therefore, the method has important significance for researching the separation and extraction technology of rubidium, cesium, lithium and potassium in the polymetallic mica ore. At present, the method for extracting elements such as lithium from polymetallic mica ore mainly comprises a lime roasting method, a pressure cooking method, a sulfuric acid method and the like.

The limestone roasting method is that limestone and lithium-containing mineral are mixed according to a certain mass ratio, wet ball milling is carried out under the condition of a certain ore pulp concentration to fine particles, the concentration is thickened, additives are added, sintering is carried out for a certain time at high temperature, water is added for leaching, filtering is carried out to obtain lithium leaching liquid, impurities are removed and purified to obtain lithium hydroxide solution, and finally, concentration crystallization or carbonization is carried out to obtain the lithium product. The method has the disadvantages of low lithium content in the leaching solution, large material flux, large energy consumption and low recovery rate; there are also drawbacks in terms of process: the aluminum removing effect is poor; the evaporation efficiency is low; the evaporation energy consumption is large; the recrystallization method has long working time for processing coarse crystals and is easy to block pipelines.

The pressure boiling method is that the polymetallic mica ore is defluorinated and roasted at high temperature in a rotary kiln, then sodium chloride, sodium carbonate or sodium hydroxide is added to the high-temperature and pressure boiling for a certain time, the leachate is purified and concentrated, and then is treated by sodium carbonate, such as sodium carbonate, to obtain lithium carbonate. The existing method for extracting lithium from polymetallic mica ore to prepare lithium carbonate mainly comprises the following steps: high-temperature roasting defluorination, grinding and pressing boiling: putting the ground polymetallic mica ore, calcium oxide and sodium salt into a high-pressure reaction kettle for pressure boiling, decomposing the polymetallic mica ore under the condition of continuous stirring, carrying out ion exchange on alkali metal in the polymetallic mica ore to convert into salt for dissolving out, removing impurities, concentrating, freezing and precipitating sodium, and finally introducing CO into a sodium precipitation mother solution₂Precipitating lithium carbonate. The disadvantages are low lithium recovery rate, high operating requirement and CO production, and the autoclave leaching is carried out at high temperature and high pressure₂And a gas regeneration system increases the production cost.

The sulfuric acid process is to react polymetallic mica ore powder with sulfuric acid at relatively low temperature to produce rubidium sulfate, cesium sulfate, lithium sulfate, potassium sulfate, calcium sulfate and magnesium sulfate, and to separate potassium, rubidium sulfate and cesium sulfate to produce lithium carbonate precipitate. The method for preparing lithium carbonate from polymetallic mica ore by using the existing sulfuric acid roasting method mainly comprises the following process flows: roasting and defluorinating; cooling and grinding; mixing slurry; roasting at low temperature; leaching and separating; removing impurities; concentrating; freezing; and carbonizing and depositing lithium to obtain a lithium carbonate product. The conventional mica treatment process for preparing lithium carbonate by using multi-metal mica ore mainly comprises the following steps: adding polymetallic mica ore-dilute sulfuric acid into a reaction kettle according to a certain proportion at high temperature and normal pressure for reaction, drying, roasting, leaching, cooling, crystallizing, removing impurities, concentrating, and precipitating lithium to obtain a lithium carbonate product. The disadvantages are that the using amount of the sulfuric acid is large, acid mist is generated during roasting, air pollution is caused, and equipment is easy to be seriously corroded. In addition, when the sulfuric acid method is used for treating the polymetallic mica ore, lithium, potassium and cesium can be released while the original ore phase structure is damaged, and a large amount of alkali is consumed for neutralizing excessive sulfuric acid subsequently.

Disclosure of Invention

In order to solve the technical problems of low comprehensive utilization rate and environmental friendliness of the polymetallic mica ore, the invention provides a method for extracting rubidium, cesium, lithium and potassium from the polymetallic mica ore.

The technical problem of the invention is solved by the following technical scheme:

a method for extracting rubidium, cesium, lithium and potassium from polymetallic mica ore comprises the following steps:

s1, uniformly mixing the polymetallic mica ore and more than two of sodium salt, potassium salt or calcium salt serving as a roasting additive, roasting, and crushing to obtain roasted sand;

s2, adding water into the calcine for leaching to obtain a leaching solution;

s3, removing impurities from the leachate, concentrating and salting out to obtain Na₂SO₄、K₂SO₄Mixing salt and a purifying solution;

s4, adding Na into the purified liquid₂CO₃Then filtering, washing and drying to obtain Li₂CO₃And contain Rb⁺And Cs⁺The solution of (1).

Preferably, in step S1, the sodium salt in the roasting additive includes NaCl and/or Na₂SO₄The potassium salt comprises KCl, and the calcium salt comprises CaCl₂And/or CaSO₄。

Preferably, in step S1, the roasting additive includes NaCl and CaSO₄Mixed salt, or CaCl₂With Na₂SO₄Mixing the salts.

Preferably, in step S1, the polymetallic mica ore and the NaCl and CaSO₄The mass ratio of the mixed salt is 1: 0.3-1: 1.2, and preferably 1: 0.5-1: 1.2; and/or the roasting temperature is 780-1000 ℃, and the preferable roasting temperature is 830-930 ℃; and/or the roasting time is 15-90 minutes, and the preferable roasting time is 30-90 minutes.

Preferably, in step S1, the polymetallic mica ore comprises Li-containing₂O is 1 to 5 percent, Rb is₂O is 0.1 to 1 percent, and Cs₂0.1 to 1 percent of O and K₂The O is 2 to 5 percent of polymetallic mica ore.

Preferably, in step S2, the liquid-solid mass ratio of the water to the calcine is 1:1 to 4:1, and the liquid-solid mass ratio of the water to the calcine is preferably 2: 1; and/or the leaching temperature is 30-80 ℃; and/or the leaching time is 2-30 minutes, and preferably the leaching time is 15-30 minutes.

Further, in step S3, the removing the impurities includes: adding NaOH with the mass fraction of 5% -30% to adjust the pH value of the leaching solution to 10-12, reacting for 5-90 minutes, and filtering to obtainRemoval of Mg²⁺And Mn²⁺The leachate of (2); and/or the salting out comprises: adding ethanol into the concentrated leachate, and filtering to obtain Na₂SO₄、K₂SO₄And mixing salt, wherein the mass ratio of the concentrated leachate to the ethanol is 1: 0.05-1: 0.2.

Further, in step S3, the method further comprises removing Mg from the substrate²⁺And Mn²⁺Ca is added to the leachate²⁺With Na₂CO₃In a mass ratio of 1:1 to 1:1.5, adding Na₂CO₃Controlling the temperature to be 30-80 ℃, and reacting for 5-60 minutes to remove Ca²⁺。

Further, the method also comprises the step of obtaining Na in step S3₂SO₄、K₂SO₄Mixed salt recrystallization treatment comprising: according to the formula Na₂SO₄、K₂SO₄Na in mixed salt₂SO₄KCl is added to prepare a saturated solution at a ratio of the KCl to the KCl in an amount of 1: 1-1: 3, and methanol is added for salting out to obtain a salted-out substance; adding the salting-out material as Na₂SO₄、K₂SO₄K in mixed salt₂SO₄With Na₂SO₄KCl is added in a ratio of 1: 1-1: 3, and the mixture is prepared into a saturated solution at 50-90 ℃, and then the saturated solution is kept stand for recrystallization to obtain K₂SO₄And (4) crystals.

Preferably, in step S4, the Na₂CO₃Has a mass concentration of 10% to 25%, wherein Li in the purification liquid⁺With said Na₂CO₃The amount ratio of the substances is 1: 0.5-1: 1, the reaction temperature is 60-95 ℃, and the reaction time is 5-30 minutes.

The invention also provides a preparation method of the Rb-containing material prepared by any one of the methods⁺And Cs⁺Use of the solution of (a) for the production of a rubidium salt and/or a cesium salt. The rubidium cesium salt can be prepared by adopting t-BAMAP as an extracting agent, one or more of sulfonated kerosene, xylene and diethylbenzene as a diluent, and hydrochloric acid, sulfuric acid, carbon dioxide and the like as a back-extraction agent. The t-BAMAP in the present invention is 4-tertButyl-2- (α -methylbenzyl) phenol.

Compared with the prior art, the invention has the advantages that: the invention adopts a method for extracting rubidium, cesium, lithium and potassium from multi-metal mica ore, more than two of added sodium salt, potassium salt and calcium salt are roasted with valuable metals in the multi-metal mica ore, an ion exchange reaction is generated, and no acidic gas such as hydrogen chloride, sulfur dioxide and the like is generated in the roasting process; water is used as a leaching agent, and no acid or alkali is added, so that the corrosion of equipment is reduced, and the method is environment-friendly; removing impurities from the leaching solution, concentrating, and salting out to obtain Na₂SO₄、K₂SO₄After mixing the salts, Na is continuously added into the purified liquid₂CO₃Then filtering, washing and drying to obtain Li₂CO₃And contain Rb⁺And Cs⁺In the preparation of Li₂CO₃Simultaneous preparation of Na from the product₂SO₄、K₂SO₄Mixing with salt to obtain final leachate with high Rb content⁺And Cs⁺The leachate can be used for extracting rubidium salt and cesium salt, and comprehensive utilization of polymetallic mica ore resources is realized.

Other beneficial effects include:

1. the leaching rate of rubidium, cesium and lithium is high: in the roasting process, the roasting additive and metal elements in the ore generate ion exchange action, the lattice structure of the ore is damaged, and the coating of the gangue on rubidium, cesium and lithium is removed. Sodium salt and calcium salt are used as combined roasting additives, which is beneficial to destroying various lattice structures in ores, thereby realizing high-efficiency extraction of rubidium, cesium and lithium. In some preferred schemes, the leaching rate of rubidium, cesium and lithium can exceed 90%, and potassium in potassium feldspar in mica ore is leached out.

2. The amount of waste residue in the purification process is reduced: because the leaching process adopts water leaching, impurity ions in the leaching solution are less, the amount of slag generated in the impurity removal process is very small, the waste slag does not contain dangerous substances, the material flow in the whole process is low, the investment of equipment, fields and manpower is greatly reduced, and the production cost is saved.

3. High purity is obtainedK₂SO₄Crystal: mixing Na₂SO₄、K₂SO₄Recrystallizing the mixed salt, and adding a certain amount of KCl twice to obtain K with purity of 95%₂SO₄And (4) crystals.

Drawings

FIG. 1 is a process flow diagram for extracting rubidium, cesium, lithium and potassium from polymetallic mica ore in an embodiment of the present invention.

Detailed Description

The invention is further described below in connection with specific examples, which may be carried out in any of the ways described in the summary of the invention and which are given by way of illustration and not by way of limitation.

The polymetallic mica ore in the present embodiment means a mica ore containing a plurality of valuable metals, and the polymetallic mica ore usually contains Li₂O is 1 to 5 percent, Rb is₂O is 0.1 to 1 percent, and Cs₂0.1 to 1 percent of O and K₂The O is 2 to 5 percent of polymetallic mica ore.

The main components and contents (%) of the polymetallic mica ore used in the examples are shown in table 1.

TABLE 1

Components	Li2O	Rb2O	Cs2O	SiO2	Al2O3	K2O	Na2O	Others
									Content (wt.)	1.36	0.42	0.46	66.18	16.95	3.72	2.61	8.3

Example 1

Mixing multi-metal mica ore with different roasting additives (NaCl, CaCl)₂、Na₂SO₄、CaSO₄NaCl and CaSO₄Mixed salt, or CaCl₂With Na₂SO₄Mixed salt) is uniformly mixed according to the mass ratio of 1:1, wherein, the baking additives of NaCl and CaSO are added₄NaCl and CaSO in mixed salt₄In a mass ratio of 1:1, roasting additives of NaCl and CaSO₄CaCl in mixed salt₂With Na₂SO₄The mass ratio of (A) to (B) is 1:1. Placing the mixture in a roasting furnace at 880 ℃ for reacting for 45 minutes, taking out the mixture after the reaction is completed, cooling to normal temperature, crushing, adding water according to the liquid-solid mass ratio of 3:1 for leaching, wherein the leaching temperature is 70 ℃, the leaching time is 20 minutes, the mechanical stirring frequency is 250 r/min, and filtering to obtain a leaching solution containing rubidium, cesium, lithium and potassium salt, wherein the leaching rates of lithium, rubidium and cesium are shown in table 2. As can be seen from Table 2, NaCl and CaSO were used₄Or CaCl₂With Na₂SO₄For roasting the additive, the leaching rate of rubidium, cesium and lithium is obviously higher than that of the additive singly usedOne of the additives is calcined. The detection of the gas generated in the roasting process shows that when NaCl is used as a roasting additive, hydrogen chloride exists in the gas; and other roasting additives are adopted, so that no hydrogen chloride gas escapes. When the roasting additive is NaCl and CaSO₄The reason why no hydrogen chloride gas escapes may be that sodium chloride is used in a relatively small amount and the generated hydrogen chloride reacts with alkali metals in the ore.

TABLE 2 results of the influence of different roasting additives on leaching yield

Example 2

Mixing the multi-metal mica ore with roasting additives NaCl and CaSO₄Uniformly mixing the mixed salt according to different mass ratios (1: 0.3-1: 1.2), and roasting NaCl and CaSO in the additive₄Placing the mixture in a roasting furnace at 880 ℃ for reacting for 45 minutes at a mass ratio of 1:1, taking out the mixture after the reaction is completed, cooling to normal temperature, crushing, adding water according to a liquid-solid mass ratio of 3:1 for leaching, wherein the leaching temperature is 70 ℃, the leaching time is 20 minutes, the mechanical stirring frequency is 250 r/min, and filtering to obtain a leaching solution containing rubidium, cesium, lithium and potassium salt, wherein the leaching rates of lithium, rubidium and cesium are shown in Table 3. As can be seen from Table 3, when the mass ratio of the polymetallic mica ore to the roasting additive is 1:0.5, the leaching rates of lithium, rubidium and cesium are all over 80%, and when the mass ratio is 1:0.7, the leaching rates of lithium and cesium are more than 90% and the leaching rate of rubidium is close to 90%.

TABLE 3 results of the leaching rate effect of different mass ratios of polymetallic mica ore to roasting additive

Example 3

Mixing the multi-metal mica ore with roasting additives NaCl and CaSO₄Uniformly mixing the mixed salt according to the mass ratio of 1:0.7, and roasting NaCl and CaSO in the additive₄The mass ratio is 1:1, the mixture is placed in roasting furnaces with different temperatures for reaction for 45 minutes until the reaction is completeAnd then taking out, cooling to normal temperature, crushing, adding water according to the liquid-solid mass ratio of 3:1 for leaching, wherein the leaching temperature is 70 ℃, the leaching time is 20 minutes, the mechanical stirring frequency is 250 r/min, and filtering to obtain a leaching solution containing rubidium, cesium, lithium and potassium salt, wherein the leaching rates of lithium, rubidium and cesium are shown in table 4. As can be seen from Table 4, the leaching rates of lithium, rubidium and cesium are all higher than 80% at the roasting temperature of 830-930 ℃, the operable temperature range is large, and when the roasting temperature is 880 ℃, the leaching rates of lithium, rubidium and cesium are all higher than 90%.

TABLE 4 results of the influence of different calcination temperatures on leaching efficiency

Example 4

Mixing the multi-metal mica ore with roasting additives NaCl and CaSO₄Uniformly mixing the mixed salt according to the mass ratio of 1:0.7, and roasting NaCl and CaSO in the additive₄Placing the materials in a roasting furnace at 880 ℃ for different times in a mass ratio of 1:2, reacting for different times, taking out the materials after the reaction is completed, cooling to normal temperature, crushing, adding water according to a liquid-solid mass ratio of 3:1 for leaching, wherein the leaching temperature is 70 ℃, the leaching time is 20 minutes, the mechanical stirring frequency is 250 r/min, and filtering to obtain a leaching solution containing rubidium, cesium, lithium and potassium salts, wherein the leaching rates of lithium, rubidium and cesium are shown in Table 5. As can be seen from Table 5, when the calcination time was longer than 30 minutes, the leaching rates of lithium, rubidium and cesium were all higher than 90%.

TABLE 5 results of the influence of different calcination times on the leaching efficiency

Example 5

Mixing the multi-metal mica ore with roasting additives NaCl and CaSO₄Uniformly mixing the mixed salt according to the mass ratio of 1:0.7, and roasting NaCl and CaSO in the additive₄Placing the mixture in a roasting furnace at 880 ℃ for reacting for 45 minutes at a mass ratio of 1:2, taking out the mixture after the reaction is completed, cooling to normal temperature, crushing, adding water to perform leaching at a liquid-solid mass ratio of 3:1, wherein the leaching temperature is 70 ℃, and taking out the mixtureAnd (3) filtering the mixture for different leaching times at a mechanical stirring frequency of 250 r/min to obtain leachate containing rubidium, cesium, lithium and potassium salts, wherein the leaching rates of lithium, rubidium and cesium are shown in table 6. As can be seen from Table 6, when the leaching time is longer than 15 minutes, the leaching rates of lithium, rubidium and cesium are all larger than 90%.

TABLE 6 results of the influence of different leaching times on leaching yield

Example 6

Mixing the multi-metal mica ore with roasting additives NaCl and CaSO₄Uniformly mixing the mixed salt according to the mass ratio of 1:0.7, and roasting NaCl and CaSO in the additive₄Placing the materials in a roasting furnace at 880 ℃ for reacting for 45 minutes at a mass ratio of 1:2, taking out the materials after the reaction is completed, cooling to normal temperature, crushing, adding water according to different liquid-solid mass ratios for leaching, wherein the leaching temperature is 70 ℃, the leaching time is 15 minutes, the mechanical stirring frequency is 250 r/min, and filtering to obtain leachate containing rubidium, cesium, lithium and potassium salts, wherein the leaching rates of lithium, rubidium and cesium are shown in table 7. As can be seen from Table 7, when the liquid-solid ratio is 2:1, the leaching rates of lithium and cesium are greater than 90%, the leaching rate of rubidium is close to 90%, and the leaching rates of the three are greater than 90%.

TABLE 7 results of the influence of different liquid-solid ratios on leaching rate

Example 7

Mixing multi-metal mica ore, NaCl, CaSO₄Uniformly mixing the raw materials according to the mass ratio of 1.00:0.23:0.46, placing the mixture in a roasting furnace at 880 ℃ for reaction for 45 minutes, taking the mixture out after the reaction is completed, cooling the mixture to normal temperature, crushing the mixture, adding water according to the liquid-solid mass ratio of 3:1 for leaching, wherein the leaching temperature is 70 ℃, the leaching time is 20 minutes, and the mechanical stirring frequency is as follows: filtering at 250 r/min to obtain leachate containing rubidium, cesium, lithium and potassium salt, wherein the leaching rates of lithium, rubidium and cesium are 93.77%, 91.12% and 92.81%, respectively.

Get onDropwise adding a NaOH solution with the mass fraction of 5% into the leachate under the condition of mechanical stirring (250 r/min) until the pH value is 11, reacting for 60 min, and filtering. Then adding Ca into the filtrate according to the mass ratio of the substances²⁺:Na₂CO₃Adding Na in the ratio of 1:1.1₂CO₃Solid, reaction temperature 60 ℃, reaction time 15 minutes, filtering. Concentrating the filtrate in the previous step until precipitation just occurs, dropwise adding ethanol into the concentrated solution according to the mass ratio of 1:0.1 under the condition of mechanical stirring (250 r/min), and filtering after the reaction is completed to obtain a solid Na₂SO₄、K₂SO₄Mixing salts, and filtering to obtain filtrate containing lithium, rubidium and cesium with high concentration.

The obtained Na₂SO₄、K₂SO₄Mixed salt according to Na therein₂SO₄Adding KCl to prepare a saturated solution, dropwise adding methanol into the saturated solution according to the volume fraction of 50% of the saturated solution under the condition of stirring, reacting for 60 minutes, filtering and drying. Drying the salted-out material at 90 deg.C according to K₂SO₄，Na₂SO₄KCl is added to prepare a saturated solution with the ratio of the total substance amount to the KCl substance amount of 1:1.2, and the saturated solution is kept stand at 5 ℃ and recrystallized to obtain K with the purity of 85.12 percent₂SO₄And (5) producing the product.

Taking the filtrate, distilling and recovering ethanol for the previous step, and then mechanically stirring (250 r/min) according to the mass ratio of Li⁺:Na₂CO₃Na with the mass fraction of 20 percent is dropwise added at the ratio of 1:0.55₂CO₃The solution is reacted at 90 ℃ for 10 minutes and filtered after the reaction is completed to obtain Li with the purity of 96.64 percent₂CO₃Products and compositions containing higher concentrations of Rb⁺、Cs⁺The solution can be used as a raw material solution for extracting rubidium salt and cesium salt.

Example 8

Mixing multi-metal mica ore and CaCl₂、Na₂SO₄Uniformly mixing the raw materials according to the mass ratio of 1:0.55:0.45, placing the mixture in a roasting furnace at 900 ℃ for reacting for 60 minutes until the mixture is ready for useTaking out after the reaction is completed, cooling to normal temperature, crushing, adding water according to the liquid-solid mass ratio of 2:1 for leaching, wherein the leaching temperature is 60 ℃, the leaching time is 15 minutes, and the mechanical stirring frequency is as follows: filtering at 200 r/min to obtain leachate containing rubidium, cesium, lithium and potassium salt, wherein leaching rates of lithium, rubidium and cesium are respectively 92.71%, 93.77% and 94.70%.

And (3) dropwise adding a 10% NaOH solution into the leachate under the condition of mechanical stirring (200 r/min) until the pH value is 12, reacting for 90 min, and filtering. Then adding Ca into the filtrate according to the mass ratio of the substances²⁺:Na₂CO₃Adding Na in the ratio of 1:1.2₂CO₃Solid, reaction temperature 60 ℃, reaction time 15 minutes, filtering. Concentrating the filtrate in the previous step until precipitation just occurs, dropwise adding ethanol into the concentrated solution according to the mass ratio of 1:0.08 under the condition of mechanical stirring (200 r/min), and filtering after the reaction is completed to obtain a solid Na₂SO₄、K₂SO₄Mixing salts, and filtering to obtain filtrate containing lithium, rubidium and cesium with high concentration.

The obtained Na₂SO₄、K₂SO₄Mixed salt according to Na therein₂SO₄Adding KCl to prepare a saturated solution, dropwise adding methanol according to the volume fraction of 60% of the saturated solution under the condition of stirring, reacting for 60 minutes, filtering and drying. Drying the salted-out material at 90 deg.C according to K₂SO₄，Na₂SO₄Adding KCl to obtain saturated solution at a ratio of total mass to KCl mass of 1:2, standing at 5 deg.C, and recrystallizing to obtain K with purity of 88.59%₂SO₄Recrystallizing the crude product again to obtain K with purity of more than 95%₂SO₄And (5) producing the product.

Taking the filtrate, and mechanically stirring (200 r/min) according to the mass ratio Li⁺:Na₂CO₃Slowly add Na ═ 1:0.6₂CO₃Solid, the reaction temperature is 85 ℃, the reaction time is 15 minutes, and after the reaction is completed, the solid is filtered to obtain Li with the purity of 93.21 percent₂CO₃Products and compositions containing higher concentrations of Rb⁺、Cs⁺The solution can be used as a raw material solution for extracting rubidium salt and cesium salt.

Example 9

Mixing multi-metal mica ore and CaCl₂、Na₂SO₄KCl is uniformly mixed according to the mass ratio of 1:0.55:0.45:0.15, the mixture is placed in a roasting furnace at 880 ℃ for reaction for 45 minutes, the mixture is taken out after the reaction is completed, the temperature is reduced to the normal temperature, the crushing is carried out, water is added according to the liquid-solid mass ratio of 2:1 for leaching, the leaching temperature is 70 ℃, the leaching time is 15 minutes, the mechanical stirring frequency is 220 r/minute, and the filtration is carried out to obtain leachate containing rubidium, cesium, lithium and sylvite, wherein the leaching rates of the lithium, rubidium and cesium are 94.92%, 90.11% and 94.75% respectively, and the leaching rate of the potassium is 33.12%.

And (3) dropwise adding a NaOH solution with the mass fraction of 20% into the leachate under the condition of mechanical stirring (220 r/min) until the pH value is 12, reacting for 60 min, and filtering. Then adding Ca into the filtrate according to the mass ratio of the substances²⁺:Na₂CO₃Adding Na in the ratio of 1:1.1₂CO₃Solid, reaction temperature 60 ℃, reaction time 15 minutes, filtering. Concentrating the filtrate in the previous step until precipitation just occurs, dropwise adding ethanol into the concentrated solution according to the mass ratio of 1:0.15 under the condition of mechanical stirring (220 r/min), and filtering after the reaction is completed to obtain a solid Na₂SO₄、K₂SO₄Mixing salts, and filtering to obtain filtrate containing lithium, rubidium and cesium with high concentration.

The obtained Na₂SO₄、K₂SO₄Mixed salt according to Na therein₂SO₄Adding KCl to prepare a saturated solution, dropwise adding methanol into the saturated solution according to the volume fraction of 50% of the saturated solution under the condition of stirring, reacting for 90 minutes, filtering and drying. Drying the salted-out material at 80 deg.C according to K₂SO₄，Na₂SO₄Adding KCl to obtain saturated solution at a ratio of total mass to KCl mass of 1:2, standing at 10 deg.C, and recrystallizing to obtain K with purity of 83.12%₂SO₄Coarse product, re-treating the coarse productPerforming secondary recrystallization to obtain K with the purity of more than 95 percent₂SO₄And (5) producing the product.

Taking the filtrate, distilling and recovering ethanol for the previous step, and then mechanically stirring (220 r/min) according to the mass ratio of Li +: Na₂CO₃Na with the mass fraction of 25 percent is dropwise added at the ratio of 1:0.65₂CO₃The solution is reacted at 90 ℃ for 15 minutes and filtered after the reaction is completed to obtain Li with the purity of 95.61 percent₂CO₃Products and compositions containing higher concentrations of Rb⁺、Cs⁺The solution can be used as a raw material solution for extracting rubidium salt and cesium salt.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (8)

1. A method for extracting rubidium, cesium, lithium and potassium from polymetallic mica ore is characterized by comprising the following steps:

s1, uniformly mixing the polymetallic mica ore and a roasting additive, roasting, and crushing to obtain roasted sand; the polymetallic mica ore contains Li₂O is 1 to 5 percent, Rb is₂O is 0.1 to 1 percent, and Cs₂0.1 to 1 percent of O and K₂The O is 2 to 5 percent of polymetallic mica ore; the roasting addition is NaCl and CaSO₄Mixing salt;

s2, adding water into the calcine for leaching to obtain a leaching solution;

s3, removing impurities from the leachate, concentrating and salting out to obtain Na₂SO₄、K₂SO₄Mixing salt and a purifying solution; the salting-out comprises the following steps: adding ethanol into the concentrated leachate, and filtering to obtain Na₂SO₄、K₂SO₄Mixing salt, wherein the mass ratio of the concentrated leachate to the ethanol is 1: 0.05-1: 0.2;

s4, adding Na into the purified liquid₂CO₃Then filtering, washing and drying to obtain Li₂CO₃And contain Rb⁺And Cs⁺The solution of (1);

s5 in the above Na₂SO₄、K₂SO₄Adding KCl into the mixed salt to prepare a saturated solution, adding methanol for salting out to obtain a salted-out substance;

s6, adding KCl into the salted-out matter to prepare a saturated solution, standing for recrystallization to obtain K₂SO₄A crystal;

s7, preparing rubidium salt and cesium salt by taking 4-tert-butyl-2- (alpha-methylbenzyl) phenol as an extracting agent, one or more of sulfonated kerosene, xylene and diethylbenzene as a diluting agent and hydrochloric acid or sulfuric acid as a back-extracting agent.

2. The method of claim 1, wherein: in step S1, the polymetallic mica ore and the NaCl and CaSO₄The mass ratio of the mixed salt is 1: 0.3-1: 1.2; the roasting temperature is 780-1000 ℃; the roasting time is 15-90 minutes.

3. The method of claim 1, wherein: in step S1, the polymetallic mica ore and the NaCl and CaSO₄The mass ratio of the mixed salt is 1: 0.5-1: 1.2; the roasting temperature is 830-930 ℃; the roasting time is 30-90 minutes.

4. The method of claim 1, wherein: in step S2, the liquid-solid mass ratio of the water to the calcine is 1: 1-4: 1; the leaching temperature is 30-80 ℃; the leaching time is 2-30 minutes.

5. The method of claim 1, wherein: in step S2, the liquid-solid mass ratio of the water to the calcine is 2: 1; the leaching time is 15-30 minutes.

6. The method of claim 1, wherein: in step S3, the removing impurities includes: adding NaOH with the mass fraction of 5% -30% to adjust the pH value of the leaching solution to 10-12, reacting for 5-90 minutes, and filtering to obtain the product with Mg removed²⁺And Mn²⁺The leachate of (2); in step S3, the method further comprises removing Mg from the substrate²⁺And Mn²⁺Ca is added to the leachate²⁺With Na₂CO₃In a mass ratio of 1:1 to 1:1.5, adding Na₂CO₃Controlling the temperature to be 30-80 ℃, and reacting for 5-60 minutes to remove Ca²⁺。

7. The method of claim 1, wherein: in step S5, the Na content is adjusted to₂SO₄、K₂SO₄Na in mixed salt₂SO₄KCl is added to prepare a saturated solution, wherein the amount ratio of the KCl to the KCl is 1: 1-1: 3; in step S6, the salted-out material is added with Na₂SO₄、K₂SO₄K in mixed salt₂SO₄With Na₂SO₄The ratio of the total substance amount to the KCl substance amount is 1: 1-1: 3, KCl is added, and a saturated solution is prepared at 50-90 ℃.

8. The method of claim 1, wherein: in step S4, the Na₂CO₃Has a mass concentration of 10% to 25%, wherein Li in the purification liquid⁺With said Na₂CO₃The amount ratio of the substances is 1: 0.5-1: 1, the reaction temperature is 60-95 ℃, and the reaction time is 5-30 minutes.

Images