A method for extracting lithium from a clay-type lithium ore

Abstract

The application provides a lithium extraction method of clay type lithium ore and relates to the technical field of lithium resource recovery. The clay type lithium ore powder, a sulfate, concentrated sulfuric acid and water are mixed, roasting (holding temperature 480-750 DEG C) is carried out, and roasting clinker and roasting flue gas are obtained respectively; the mass ratio of the clay type lithium ore powder, the sulfate and the sulfuric acid is 1:0.03-0.25:0.18-0.6; the roasting clinker is subjected to water immersion, and a lithium leaching solution is obtained. The application uses the clay type lithium ore as raw material, realizes lithium recovery through roasting and water immersion, and the lithium extraction process flow is simple; by controlling the dosage ratio of the clay type lithium ore powder, the sulfate and the sulfuric acid and the roasting temperature, the lithium leaching rate is greatly improved; the dosages of the sulfate and the concentrated sulfuric acid are small, the roasting temperature is low, energy consumption is low, the acidity of the leaching solution is weak, the consumption of the subsequent lithium extraction and impurity removal alkali can be greatly reduced, the lithium extraction process cost is greatly reduced; the roasting flue gas is absorbed by water or dilute sulfuric acid, and the recycling of sulfuric acid is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lithium resource recovery, in particular to a lithium extraction method for clay-type lithium ore. BACKGROUND

[0002] Lithium is known as a key strategic resource in the development of high-tech in the 21st century, is an ideal electrode material for batteries, and is a core metal supporting the development of lithium battery new energy industry. Clay-type lithium ore is a new type of lithium ore, and with the popularization of new energy electric vehicles in recent years, its production and consumption are increasing year by year. Extracting lithium from clay-type lithium ore will be one of the important sources of lithium. At present, the methods for extracting lithium from lithium ore mainly include limestone calcination, sulfuric acid method, sulfate mixed roasting, and chlorination roasting.

[0003] Chinese patent CN103849761A discloses a method for extracting lithium from low-grade lithium-containing clay ore, which includes the following steps: crushing the potassium-containing clay ore to 2mm, mixing the crushed ore with calcium sulfate, calcium fluoride and sodium sulfate in a mass ratio of 1:0.7:0.2:0.5, and then calcining the mixture at 800℃ for 2-3h. The calcined material is granulated and leached, and the highest lithium leaching rate is 91.78%. The prior art process is complex, the calcination temperature is high, the energy consumption is high, the consumption of calcination additives such as calcium sulfate, calcium fluoride and sodium sulfate is large, and the cost is high.

[0004] Chinese patent CN114892024A discloses a method for extracting lithium from lithium-containing clay by low-temperature calcination, which includes the following steps: mixing 98% sulfuric acid with lithium-containing clay in a liquid-solid ratio of 0.5:1-1:2, and then calcining the mixture at a temperature of 180-250℃. The calcined product is subjected to water leaching and then suction filtration to obtain a lithium-containing filtrate. In the prior art, the lithium leaching rate is below 89.32%, the lithium leaching rate is low, the acidity is strong, a large amount of alkali is consumed for subsequent lithium extraction and impurity removal, and the lithium extraction process cost is high.

[0005] Chinese patent CN113104867A discloses a method for preparing lithium carbonate from composite sulfate acid roasting lepidolite, which comprises the following steps: mixing 55-65 parts by mass of lepidolite ore powder, 25-35 parts by mass of composite sulfate, and 2-5 parts by mass of auxiliary agent uniformly, then putting into high-performance ball milling equipment for mechanical activation treatment, then adding 1-4 parts by mass of concentrated sulfuric acid and mixing uniformly, and then entering a rotary kiln at a uniform speed at 830-880 DEG C for roasting, crushing the clinker after roasting, leaching, impurity removal, and preparing lithium carbonate product; wherein the composite sulfate is at least two of potassium sulfate, sodium sulfate, calcium sulfate, barium sulfate, and iron sulfate, and the auxiliary agent is barium carbonate and / or calcium carbonate; the mass ratio of lepidolite ore powder: composite sulfate: auxiliary agent = 1:0.39-0.64:0.03-0.09, and the highest lithium leaching rate is 92%. The prior art has the problems of large amount of composite sulfate, the need for high-performance ball milling equipment for mechanical activation treatment after mixing, complex process, and high energy consumption of the rotary kiln at 830-880 DEG C for roasting.

[0006] JULingyan et al. (JULingyan, LIANGXianzhi, LIUYeLong, et al. Lithium extraction process of medium and low grade lepidolite by Na2SO4-H2SO4 mixed roasting [J]. Nonferrous Metals Engineering, 2021, 11(11): 48-55.) discloses a lithium extraction process of medium and low grade lepidolite by Na2SO4-H2SO4 mixed roasting, which comprises the following steps: weighing a certain amount of lepidolite ore, adding a pre-prepared sulfuric acid solution in a mass ratio of 1:1, adding a certain amount of sodium sulfate, mixing the materials thoroughly, transferring the materials to a muffle furnace for pre-roasting at 280 DEG C for 2h, then quickly taking out the materials and crushing them into blocks, then continuing to put the crushed materials into the muffle furnace and heating to 800-1000 DEG C for roasting for 2h, then cooling the materials, grinding them to a certain particle size with a grinder, and then leaching with hot water; when the sulfuric acid concentration is 70% and the mass ratio of lepidolite ore:sodium sulfate = 1:0.2, the highest lithium leaching rate can reach 90%. The prior art adopts two-stage roasting, which has a complex process flow and high energy consumption.

[0007] Therefore, it is of great significance to provide a lithium recovery method with high lithium leaching rate and low cost. SUMMARY

[0008] Therefore, it is of great significance to provide a lithium recovery method with high lithium leaching rate and low cost.

[0009] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical solutions:

[0010] The present application provides a lithium extraction method of clay type lithium ore, which comprises the following steps:

[0011] (1) mixing clay-type lithium ore powder, sulfate, concentrated sulfuric acid and water, roasting to obtain roasted clinker and roasted flue gas respectively; the mass ratio of the clay-type lithium ore powder and the sulfate is 1:0.03-0.25, and the mass ratio of the clay-type lithium ore powder and the concentrated sulfuric acid is 1:0.18-0.6; the roasting temperature is 480-750℃;

[0012] (2) water leaching the roasted clinker to obtain a lithium leaching solution.

[0013] Preferably, in step (1), the mass fraction of the concentrated sulfuric acid is ≥90%.

[0014] Preferably, in step (1), the sulfate includes sodium sulfate and / or potassium sulfate.

[0015] Preferably, in step (1), the mass ratio of the clay-type lithium ore powder and water is 1:0.05-0.6.

[0016] Preferably, in step (1), the holding time of the roasting is 2-8h.

[0017] Preferably, in step (1), the temperature rising rate from room temperature to the roasting temperature is 10-20℃ / min.

[0018] Preferably, in step (2), the mass ratio of the roasted clinker and water is 1:2-4.

[0019] Preferably, in step (2), the water leaching temperature is 15-100℃, and the time is 0.5-2h.

[0020] Preferably, the lithium extraction method further comprises:

[0021] (3) using water or dilute sulfuric acid to absorb the roasted flue gas to obtain a sulfuric acid solution; when the mass fraction of the sulfuric acid solution is ≥90%, it is used as concentrated sulfuric acid in step (1);

[0022] Step (2) and step (3) have no time sequence.

[0023] Preferably, the mass fraction of the dilute sulfuric acid is 0.5-10%.

[0024] The application provides a lithium extraction method of clay-type lithium ore, comprising the following steps: (1) mixing clay-type lithium ore powder, sulfate, concentrated sulfuric acid and water, and performing roasting to obtain roasting clinker and roasting flue gas respectively; the mass ratio of the clay-type lithium ore powder and the sulfate is 1:0.03-0.25, and the mass ratio of the clay-type lithium ore powder and the concentrated sulfuric acid is 1:0.18-0.6; the roasting temperature is 480-750 DEG C; (2) performing water immersion on the roasting clinker to obtain a lithium leaching solution. The lithium recovery can be realized by roasting and water immersion of the clay-type lithium ore as raw material, and the lithium extraction process flow is simple; by controlling the dosage ratio of the clay-type lithium ore powder, the sulfate and the sulfuric acid and the roasting temperature, the lithium leaching rate is greatly improved; moreover, the dosages of the sulfate and the concentrated sulfuric acid are small, the roasting temperature is low, the energy consumption is low, the acidity of the leaching solution is weak, the subsequent lithium extraction and impurity removal alkali consumption can be greatly reduced, and the lithium extraction process cost is greatly reduced. As shown in the test results of the examples, the lithium extraction method provided by the application has a lithium leaching rate of 96.66%, and the pH value of the lithium leaching solution is above 3.2.

[0025] Further, the lithium extraction method provided by the application recovers the roasting flue gas by using water or dilute sulfuric acid, and when the mass fraction of the sulfuric acid solution is greater than or equal to 90%, the concentrated sulfuric acid is reused in step (1), the recycling of the sulfuric acid is realized, and the lithium extraction cost is reduced. DETAILED DESCRIPTION

[0026] The application provides a lithium extraction method of clay-type lithium ore, comprising the following steps:

[0027] (1) mixing clay-type lithium ore powder, sulfate, concentrated sulfuric acid and water, and performing roasting to obtain roasting clinker and roasting flue gas respectively; the mass ratio of the clay-type lithium ore powder: the sulfate and the sulfuric acid is 1:0.03-0.25:0.18-0.6; the roasting temperature is 480-750 DEG C;

[0028] (2) performing water immersion on the roasting clinker to obtain a lithium leaching solution.

[0029] Unless otherwise specified, the raw materials used in the application are all commercially available goods.

[0030] The application mixes clay-type lithium ore powder, sulfate, concentrated sulfuric acid and water, and performs roasting to obtain roasting clinker and roasting flue gas respectively.

[0031] In the application, the mass percentage content of particle size <0.074 mm in the clay-type lithium ore powder is greater than or equal to 65%; the clay-type lithium ore powder is preferably obtained by crushing clay-type lithium ore; and the crushing mode is preferably grinding.

[0032] In the present application, the mass fraction of the concentrated sulfuric acid is preferably ≥ 90%, more preferably 90-98%, and further preferably 95-98%. In the present application, the mass ratio of the clay-type lithium ore powder to the concentrated sulfuric acid is preferably 1:0.18-0.6, more preferably 1:0.2-0.5, and further preferably 1:0.3-0.4.

[0033] In the present application, the sulfate preferably includes sodium sulfate and / or potassium sulfate. In the present application, the mass ratio of the clay-type lithium ore powder to the sulfate is preferably 1:0.03-0.25, more preferably 1:0.1-0.2, and further preferably 1:0.15-0.2. In the present application, when the sulfate preferably includes sodium sulfate and potassium sulfate, the mass ratio of the clay-type lithium ore powder to the sulfate is more preferably 1:0.03-0.1, and further preferably 1:0.05-0.1.

[0034] In the present application, the mass ratio of the clay-type lithium ore powder to water is preferably 1:0.05-0.6, more preferably 1:0.1-0.45, and particularly preferably 1:0.11, 1:0.21, 1:0.23, 1:0.25, 1:0.27, 1:0.32, 1:0.42, 1:0.45, or 1:0.6.

[0035] The mixing in the present application is not particularly limited, and the raw materials can be mixed uniformly, for example, by stirring.

[0036] In the present application, the temperature of the calcination is preferably 480-750°C, more preferably 550-700°C, and further preferably 600-650°C; the temperature increase rate from room temperature to the temperature of the calcination is preferably 10-20°C / min, more preferably 12-18°C / min, and further 15°C / min; and the holding time of the calcination is preferably 2-8h, more preferably 2-5h, and further preferably 2-3h.

[0037] After the calcination is completed, the present application preferably further includes cooling the obtained calcined material to room temperature and then crushing it to a mass percentage content of particles with a particle size <0.074mm of ≥ 50%. The cooling in the present application is not particularly limited, and any cooling method known to those skilled in the art can be used, for example, natural cooling. In the present application, the crushing method is preferably grinding.

[0038] After the calcined material is obtained, the present application performs water leaching on the calcined material to obtain a lithium leaching solution.

[0039] In the present application, the mass ratio of the calcined material to water is preferably 1:2-4, more preferably 1:2.5-3.5, and further preferably 1:3.

[0040] In the present application, the temperature of the water immersion is preferably 15-100℃, more preferably 30-90℃, and further preferably 50-80℃; and the time of the water immersion is preferably 0.5-2h, more preferably 1-1.5h.

[0041] After the water immersion, the present application preferably further comprises solid-liquid separation, and the obtained liquid component is a lithium leaching solution. The present application does not have special limitations on the solid-liquid separation, and any leaching method known to those skilled in the art can be used, such as filtration, suction filtration or centrifugal separation. In the present application, the pH value of the lithium leaching solution is preferably ≥3.0, more preferably 3.0-4.5, and further preferably 3.2-4.3.

[0042] After obtaining the roasting flue gas, the present application preferably further comprises absorbing the roasting flue gas with water or dilute sulfuric acid to obtain a sulfuric acid solution; when the mass fraction of the sulfuric acid solution is ≥90%, it is used as concentrated sulfuric acid in step (1); in the present application, the mass fraction of the dilute sulfuric acid is preferably 0.5-10%, more preferably 1-8%, and further preferably 3-5%.

[0043] The lithium extraction method for clay-type lithium ore provided by the present application will be described in detail below in conjunction with examples, but they should not be understood as limitations on the scope of protection of the present application.

[0044] Example 1

[0045] Table 1 Multi-element analysis (wt%) of clay-type lithium ore

[0046] Element Li2O Al2O3 SiO2 [TFe2O3] TiO2 CaO MgO K2O Na2O MnO2 TS Content 0.55 21.2 52.49 7.15 0.88 5.05 0.35 1.32 0.08 0.1 0.046

[0047] (1) The clay-type lithium ore shown in Table 1 was ground and crushed to a mass content of ≥65% in the -0.074mm particle size fraction to obtain a clay-type lithium ore powder; the clay-type lithium ore powder, sulfate, 98wt% concentrated sulfuric acid and water were thoroughly stirred and mixed, heated to the roasting temperature at a heating rate of 15℃ / min, and then held for 3h to obtain a roasting clinker and roasting flue gas, respectively; the mass ratio of the clay-type lithium ore powder, sulfate, 98wt% concentrated sulfuric acid and water, and the roasting temperature are shown in Table 2.

[0048] (2) The roasting clinker was cooled to room temperature and then ground to a mass content of ≥50% in the -0.074mm particle size fraction, water immersed at 80℃ for 1h, and then filtered, and the obtained liquid component was a lithium leaching solution; the mass ratio of the roasting clinker to the water for water immersion was 1:3; the lithium leaching rate and the pH value of the lithium leaching solution are shown in Table 2.

[0049] (3) The roasting flue gas was absorbed with 5wt% dilute sulfuric acid to obtain a sulfuric acid solution; when the mass fraction of the sulfuric acid solution was ≥90%, it was used as concentrated sulfuric acid in step (1);

[0050] Examples 2-7

[0051] The lithium extraction was carried out according to the method of Example 1, with the difference in the conditions of the lithium extraction method of Example 1 as shown in Table 2, and the lithium leaching rate and the pH value of the lithium leaching solution as shown in Table 2.

[0052] Table 2 Conditions of lithium extraction, lithium leaching rate and pH value of lithium leaching solution in Examples 1-7

[0053]

[0054]

[0055] As can be seen from Table 2, the lithium extraction method provided by the present application has low roasting temperature, high lithium leaching rate and high pH value of the lithium leaching solution, and low lithium extraction cost.

[0056] Examples 8-39

[0057] The clay-type lithium ore shown in Table 3 was used to carry out lithium extraction according to the method of Example 1, with the difference in the conditions of the lithium extraction method of Example 1 as shown in Tables 4-5, and the lithium leaching rate and the pH value of the lithium leaching solution as shown in Tables 4-5.

[0058] Table 3 Multi-element analysis (wt%) of clay-type lithium ore

[0059] Element Li2O Al2O3 SiO2 [TFe2O3] CaO MgO K2O Na2O Content 0.83 24.07 43.70 3.20 9.77 0.44 1.63 0.10

[0060] Comparative Examples 1-20

[0061] The clay-type lithium ore shown in Table 3 was used to carry out lithium extraction according to the method of Example 1, with the difference in the conditions of the lithium extraction method of Example 1 as shown in Table 5, and the lithium leaching rate and the pH value of the lithium leaching solution as shown in Table 5.

[0062] Table 4 Conditions of lithium extraction, lithium leaching rate and pH value of lithium leaching solution in Examples 8-35 and Comparative Examples 1-19

[0063]

[0064]

[0065]

[0066] Table 5 Conditions of lithium extraction, lithium leaching rate and pH value of lithium leaching solution in Examples 36-39 and Comparative Example 20

[0067]

[0068]

[0069] As shown in Tables 4-5, the lithium extraction method provided by the application has low roasting temperature, high lithium leaching rate, high pH value of lithium leaching solution and low lithium extraction cost.

[0070] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered within the protection scope of the present application.

Claims

1. A method for lithium extraction from a clay-type lithium ore, characterized in that, The method comprises the following steps: (1) mixing clay-type lithium ore powder, sulfate, concentrated sulfuric acid and water, roasting to obtain roasted clinker and roasted flue gas, respectively; the mass ratio of the clay-type lithium ore powder to the sulfate is 1:0.03-0.25, and the mass ratio of the clay-type lithium ore powder to the concentrated sulfuric acid is 1:0.18-0.6; the roasting temperature is 480-750 ℃; the temperature rising rate from room temperature to the roasting temperature is 10-20 ℃ / min; the sulfate comprises sodium sulfate and / or potassium sulfate; (2) water leaching the roasted clinker to obtain a lithium leaching solution.

2. The method of claim 1, wherein, In step (1), the mass fraction of the concentrated sulfuric acid is ≥90%.

3. The lithium extraction method according to claim 1, characterized in that, In step (1), the mass ratio of the clay-type lithium ore powder to water is 1:0.05-0.

6.

4. The method of claim 1, wherein, In step (1), the holding time of the roasting is 2-8 h.

5. The method of claim 1, wherein, In step (2), the mass ratio of the roasted clinker to water is 1:2-4.

6. The method of claim 1 or 5, wherein, In step (2), the water leaching temperature is 15-100 ℃, and the time is 0.5-2 h.

7. The method for lithium extraction according to any one of claims 1 to 5, wherein The lithium extraction method further comprises: (3) using water or dilute sulfuric acid to absorb the roasted flue gas to obtain a sulfuric acid solution; when the mass fraction of the sulfuric acid solution is ≥90%, the sulfuric acid solution is used as concentrated sulfuric acid in step (1); Steps (2) and (3) have no time sequence.

8. The method of claim 7, wherein the lithium is extracted by, The mass fraction of the dilute sulfuric acid is 0.5-10%.

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