Method for extracting lithium and aluminum from red mud in cooperation with lithium porcelain stone

Abstract

The present disclosure belongs to the field of lithium ore metallurgy. The present disclosure provides a method for extracting lithium and aluminum from red mud and lithium pegmatite, which comprises mixing lithium pegmatite with red mud for primary roasting, soaking the mixture in water to obtain a soaked material, and then performing secondary roasting, followed by primary leaching of the secondary roasting, and then obtaining a qualified lithium liquid product after impurity removal of the leaching solution, and obtaining an aluminum solution with high aluminum content after secondary leaching of the leaching residue, thereby realizing simultaneous extraction of lithium and aluminum and effectively separating the two. The method uses red mud, which is also an industrial solid waste, as a raw material to extract lithium directly from lithium pegmatite ore raw materials. The process is simple and reliable, the production cost is low, the lithium recovery rate is high and can reach more than 98.7%, it is conducive to large-scale industrialization, and it makes full use of industrial solid waste, which is more green and environmentally friendly, and has considerable economic benefits.

Description

Technical Field

[0001] This disclosure pertains to the field of metallurgical production and relates to a lithium extraction technology from lithium ore, particularly a method for extracting lithium and aluminum using red mud in conjunction with lithium ceramic stone. Background Technology

[0002] Currently, the production of high-purity lithium products (lithium extraction technology) mainly falls into two categories: lithium extraction from lithium ore and lithium extraction from salt lakes. Among these, the production share of lithium extracted from salt lakes has always been relatively low, mainly due to the following two factors: ① Salt lake resources are generally concentrated in high-altitude areas, which have harsh climate conditions and inconvenient transportation; ② The extraction technology of high lithium-magnesium ratio brine is still in the initial exploration stage.

[0003] Therefore, lithium extraction from ore still dominates the market. Currently, the main raw materials for lithium extraction from ore are spodumene and lithium clay. However, lithium ore resources are limited, and in the future, they will inevitably face the unfavorable situation of declining grade and resource depletion.

[0004] Lithium porcelain stone is a type of lithium ore; however, its chemical composition and microstructure differ from spodumene and lithium clay. Lithium porcelain stone has a lower lithium content than spodumene and a more complex microstructure. Currently used lithium extraction methods are not suitable for lithium porcelain stone, making lithium extraction from it quite difficult and often requiring specific solutions.

[0005] Currently, lithium extraction from lithium porcelain stone generally involves two steps: first, extracting lepidolite from the ore through mineral processing; then, extracting lithium from the lepidolite. CN108014901A discloses a process for extracting lepidolite from lithium porcelain stone ore. This method uses impact ore particles, gravity flotation, and continuous high-gradient strong magnetic purification to finally obtain feldspar and lepidolite; however, this method has a complex processing flow and only yields lepidolite concentrate. CN113957268A discloses a method for extracting lithium from lithium porcelain stone raw materials, which uses a composite salt composed of sodium sulfate, calcium sulfate, and calcium carbonate as a roasting material; however, this method generates a large amount of calcium silicate waste residue, which is difficult to treat.

[0006] It can be seen that the existing technology generates a large amount of tailings in the process of obtaining lepidolite from lithium porcelain stone, which consumes a lot of energy and manpower, resulting in high costs. Moreover, the lithium recovery rate in the complete lithium extraction process from lithium porcelain stone is only about 65%, which will cause a lot of waste of resources.

[0007] Therefore, it is necessary to develop a new scheme for lithium extraction from lithium porcelain stone ore to provide a new way to extract and produce lithium, thereby alleviating the tight supply of lithium from ore and ensuring a low-cost and stable supply of lithium-containing products. Summary of the Invention

[0008] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims.

[0009] The purpose of this disclosure is to provide a method for lithium and aluminum extraction using red mud in conjunction with lithium porcelain stone. The method involves first mixing lithium porcelain stone and red mud and roasting them once, then soaking them in water to obtain a leached material, followed by a second roasting. The second roasted material is then leached once, and the resulting leachate is purified to obtain a qualified lithium solution. The leaching residue is then leached a second time to obtain an aluminum solution with a high aluminum content, thus achieving simultaneous lithium and aluminum extraction and effective separation of the two. This method utilizes red mud, also an industrial solid waste, as a raw material to directly extract lithium from lithium porcelain stone ore. The process is simple and reliable, with low production costs and a high lithium recovery rate, reaching up to 98.7% or more. It is suitable for large-scale industrialization and makes extensive use of industrial solid waste, making it more environmentally friendly and offering considerable economic benefits.

[0010] To achieve this objective, the present disclosure adopts the following technical solution:

[0011] This disclosure provides a method for lithium and aluminum extraction using red mud in conjunction with lithium ceramic stone, comprising the following steps:

[0012] S1: Lithium ceramic stone is mixed with red mud and then roasted once to obtain a first-roasted material;

[0013] S2: Mix the first-fired material with red mud and soak it to obtain the soaked material;

[0014] S3: The soaked material is roasted a second time to obtain the roasted material;

[0015] S4: Perform a first leaching of the secondary roasted material to obtain leachate and leachate residue;

[0016] S5: Remove impurities from the leachate to obtain metallurgical slag and lithium liquid products;

[0017] S6: The leaching residue is leached a second time to obtain silicon slag and aluminum solution;

[0018] Steps S5 and S6 are not in any particular order.

[0019] Red mud is an industrial solid waste discharged during the extraction of alumina in the aluminum industry. Due to its high iron oxide content, it resembles reddish soil in appearance, hence the name "red mud." However, some varieties, with lower iron oxide content, are brown or even grayish-white. Red mud is an insoluble residue and can be classified into sintering process red mud, Bayer process red mud, and combined process red mud. Its main components are SiO2, Al2O3, CaO, and Fe2O3. With the increasing amount of red mud stockpiles and the growing environmental pollution they cause, maximizing its resource utilization is now imperative.

[0020] This disclosure proposes a method for the efficient extraction of lithium and aluminum through the synergistic use of red mud and lithium porcelain stone ore. The method employs a pyrometallurgical process for lithium extraction, leveraging the high-temperature ion displacement mechanism to achieve efficient lithium extraction. First, lithium porcelain stone and red mud are mixed to ensure thorough contact. Then, the mixture is roasted once. At high temperatures, the crystal structure of the lithium porcelain stone ore changes, and the ion bonds break, leading to the extraction of lithium. + It readily substitutes for metal ions such as Fe, Na, and K in red mud. Then, the primary roasted material is mixed with red mud and soaked in water. Red mud itself is strongly alkaline, and after a second roasting, the ionic bonds break more thoroughly, resulting in better lithium extraction. Finally, under the action of a leaching agent, lithium is dissolved in the solution for leaching (i.e., primary leaching). The resulting leachate is a lithium solution with a high lithium content. Further purification of the lithium solution yields the lithium product, which can be directly used for lithium precipitation. Of course, those skilled in the art can also perform other treatments or uses on the high-lithium leachate according to actual needs. This disclosure allows for the selective extraction of aluminum from the primary leaching material through a secondary leaching process. The method has a high lithium extraction rate, reaching up to 98.7% or more, and the resulting aluminum solution has a high aluminum content, which can be further applied.

[0021] It should be noted that this disclosure adds red mud in two steps to avoid the problem of excessive red mud addition in a single step, which would result in hard roasted residue that would be difficult to process later. Therefore, adding it in two steps is more reasonable, with the second step primarily aimed at ensuring a more complete reaction. Similarly, if red mud is added in two steps but the total amount added is excessive, it will not only lead to waste but also cause severe material agglomeration, making subsequent processing cumbersome and increasing processing costs, and it will also affect the leaching rate.

[0022] This disclosure aims to address the problems of complex processes, long workflows, low lithium recovery rates, and difficulty in resource utilization of waste residue in traditional lithium ceramic stone extraction processes. The method described in this disclosure not only makes large-scale use of industrial solid waste red mud but also enables direct lithium extraction from lithium ceramic stone ore. The process is simple, reliable, and cost-effective, with a high lithium recovery rate, making it easy to scale up for industrial production. It has broad applicability, aligns with green development, and represents a leading-edge innovation.

[0023] The following are optional technical solutions of this disclosure, but are not intended to limit the technical solutions provided by this disclosure. The technical objectives and beneficial effects of this disclosure can be better achieved through the following technical solutions.

[0024] As an optional technical solution of this disclosure, the lithium ceramic stone and red mud described in step S1 are first mixed and crushed, and then roasted once.

[0025] In one embodiment, after the mixing and crushing, the particle size of the lithium ceramic stone and the red mud is 150-300 mesh, such as 150 mesh, 160 mesh, 170 mesh, 180 mesh, 190 mesh, 200 mesh, 210 mesh, 220 mesh, 230 mesh, 240 mesh, 250 mesh, 260 mesh, 270 mesh, 280 mesh, 290 mesh or 300 mesh, etc., and can be selected as 200-250 mesh, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0026] As an optional technical solution of this disclosure, the mass ratio of lithium ceramic stone to red mud in step S1 is 1:(0.2~0.8), such as 1:0.2, 1:0.25, 1:0.3, 1:0.35, 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, 1:0.65, 1:0.7, 1:0.75 or 1:0.8, etc., and can be selected as 1:(0.4~0.6), but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0027] As an optional technical solution of this disclosure, the temperature of the first roasting in step S1 is 750-950℃, such as 750℃, 760℃, 770℃, 780℃, 790℃, 800℃, 810℃, 820℃, 830℃, 840℃, 850℃, 860℃, 870℃, 880℃, 890℃, 900℃, 910℃, 920℃, 930℃, 940℃ or 950℃, etc., and can be selected as 800-850℃, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0028] If the temperature of the first roasting is too low, the roasting effect will be poor, and if the temperature is too high, the leaching rate will not be significantly improved.

[0029] In one embodiment, the roasting time in step S1 is 1 to 3 hours, such as 1 hour, 1.2 hours, 1.4 hours, 1.6 hours, 1.8 hours, 2 hours, 2.2 hours, 2.4 hours, 2.6 hours, 2.8 hours, or 3 hours, and can be selected as 1.5 to 2.5 hours, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0030] As an optional technical solution of this disclosure, the red mud mentioned in step S2 is red mud with a particle size of 150 to 300 mesh after crushing, such as 150 mesh, 160 mesh, 170 mesh, 180 mesh, 190 mesh, 200 mesh, 210 mesh, 220 mesh, 230 mesh, 240 mesh, 250 mesh, 260 mesh, 270 mesh, 280 mesh, 290 mesh or 300 mesh, etc. It can be selected as 200 to 250 mesh, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0031] As an optional technical solution of this disclosure, the mass ratio of the primary roasting material to the red mud in step S2 is 1:(0.2~0.8), such as 1:0.2, 1:0.25, 1:0.3, 1:0.35, 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, 1:0.65, 1:0.7, 1:0.75 or 1:0.8, etc., and can be selected as 1:(0.4~0.6), but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0032] As an optional technical solution of this disclosure, the soaking solution in step S2 includes water.

[0033] In one embodiment, the mass ratio of the total mass of the primary roasting material and the red mud to the mass of water is (0.8 to 1.5):1, for example, 0.8:1, 0.85:1, 0.9:1, 0.95:1, 1:1, 1.05:1, 1.1:1, 1.15:1, 1.2:1, 1.25:1, 1.3:1, 1.35:1, 1.4:1, 1.45:1, or 1.5:1, etc., and can be selected as (0.8 to 1):1, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0034] The soaking material obtained by this disclosure is similar to a soft dough or thin dough made by mixing flour and water, so there is no need to separate the solid and liquid components, and it can be directly roasted a second time.

[0035] As an optional technical solution of this disclosure, the secondary calcination in step S3 is carried out under vacuum.

[0036] The secondary calcination is carried out under vacuum to apply high pressure to the material, making ion exchange more thorough and thus improving the leaching rate. At this time, the vacuum degree can be adjusted as needed, and sintering can be carried out using a conventional vacuum furnace.

[0037] In one embodiment, the temperature of the secondary calcination is 850–1000°C, such as 850°C, 860°C, 870°C, 880°C, 890°C, 900°C, 910°C, 920°C, 930°C, 940°C, 950°C, 960°C, 970°C, 980°C, 990°C, or 1000°C, etc. It can be selected as 850–950°C, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0038] In one embodiment, the secondary roasting time is 2 to 5 hours, such as 2 hours, 2.2 hours, 2.4 hours, 2.6 hours, 2.8 hours, 3 hours, 3.2 hours, 3.4 hours, 3.6 hours, 3.8 hours, 4 hours, 4.2 hours, 4.4 hours, 4.6 hours, 4.8 hours, or 5 hours, and may be selected as 3 to 4.5 hours, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0039] As an optional technical solution of this disclosure, the primary leaching in step S4 and the secondary leaching in step S6 involve mixing the secondary roasted material and the leaching residue with the leaching agent respectively, and then performing solid-liquid separation after leaching is completed.

[0040] In one embodiment, the leaching agent comprises any one or a combination of at least two of water, hydrochloric acid solution, or sulfuric acid solution, with typical but non-limiting examples including combinations of water and hydrochloric acid solution, water and sulfuric acid solution, or hydrochloric acid solution and sulfuric acid solution, optionally a sulfuric acid solution.

[0041] In one embodiment, when the leaching agent comprises hydrochloric acid solution and / or sulfuric acid solution, the concentration of the leaching agent is 6 to 12 mol / L, such as 6 mol / L, 6.5 mol / L, 7 mol / L, 7.5 mol / L, 8 mol / L, 8.5 mol / L, 9 mol / L, 9.5 mol / L, 10 mol / L, 10.5 mol / L, 11 mol / L, 11.5 mol / L, or 12 mol / L, etc., and may be selected as 8 to 10 mol / L, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0042] In one embodiment, in the primary leaching and the secondary leaching, the liquid-to-solid ratio of the leaching agent to the secondary roasted material and the leaching residue is (3-5) mL:1g, for example, 3mL:1g, 3.2mL:1g, 3.4mL:1g, 3.6mL:1g, 3.8mL:1g, 4mL:1g, 4.2mL:1g, 4.4mL:1g, 4.6mL:1g, 4.8mL:1g or 5mL:1g, etc. 3mL:1g can be selected, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0043] As an optional technical solution of this disclosure, the impurity removal method in step S5 includes removing nickel, cobalt and manganese by adding liquid alkali using a chemical method, and then removing calcium and magnesium by deep resin removal.

[0044] The purpose of the impurity removal is to transform the leachate into a lithium liquid product that meets the requirements for lithium precipitation. It mainly removes impurity elements such as nickel, cobalt, manganese, calcium, magnesium, phosphorus, and fluorine. The resulting metallurgical slag is mainly a solid slag produced during the impurity removal process, and its components include nickel, cobalt, and manganese hydroxide, calcium fluoride, etc.

[0045] As an optional technical solution of this disclosure, the method includes the following steps:

[0046] (1) Lithium porcelain stone and red mud are mixed and crushed in a mass ratio of 1:(0.4~0.6) to obtain mixed crushed material, wherein the particle size of lithium porcelain stone and red mud is 200~250 mesh. The mixed crushed material is calcined at 800~850℃ for 1.5~2.5h to obtain calcined material.

[0047] (2) Take red mud with a particle size of 200-250 mesh after crushing, mix the primary roasting material with the red mud at a mass ratio of 1:(0.4-0.6), and soak it in water. Control the mass ratio of the total mass of the primary roasting material and the red mud to the mass of water to be (0.8-1):1 to obtain the soaked material.

[0048] (3) The soaked material is subjected to secondary calcination under vacuum at 850-950℃ for 3-4.5h to obtain secondary calcined material;

[0049] (4) Mix the secondary roasted material with a leaching agent, wherein the leaching agent includes water, or any one or a combination of at least two of hydrochloric acid solution or sulfuric acid solution with a concentration of 8-10 mol / L, and control the liquid-solid ratio of the leaching agent to the secondary roasted material to be (3-5) mL:1g. The secondary roasted material is leached once, and after solid-liquid separation, leaching solution and leaching residue are obtained.

[0050] (5) Remove impurities from the leachate to obtain metallurgical slag and lithium liquid products;

[0051] (6) Mix the leaching residue with the leaching agent, wherein the leaching agent includes water, or any one or a combination of at least two of hydrochloric acid solution or sulfuric acid solution with a concentration of 8-10 mol / L, and control the liquid-solid ratio of the leaching agent to the leaching residue to be (3-5) mL:1g, and perform secondary leaching on the leaching residue. After solid-liquid separation, silicon slag and aluminum solution are obtained.

[0052] Steps S5 and S6 are not in any particular order.

[0053] Compared with existing technical solutions, this disclosure has at least the following beneficial effects:

[0054] The method for lithium-aluminum extraction using red mud in conjunction with lithium ceramic stone disclosed herein can solve the problems of complex processes, long procedures, low lithium recovery rates, and difficulty in resource utilization of waste residue in traditional lithium ceramic stone lithium extraction processes. This method not only makes large-scale use of industrial solid waste red mud, but also enables direct extraction of lithium from lithium ceramic stone ore. The process is simple, reliable, and has low production costs. Furthermore, the lithium recovery rate is very high, reaching up to 98.7% or more. The resulting aluminum solution is a high-alumina solution, and the obtained silicon slag is silicon slag. This method is easy to industrialize, has wide applicability, conforms to green development, and has considerable economic benefits.

[0055] After reading and understanding the accompanying diagrams and detailed descriptions, the other aspects can be understood. Attached Figure Description

[0056] The accompanying drawings are used to provide a further understanding of the technical solutions in this paper and form part of the specification. They are used together with the embodiments of this application to explain the technical solutions in this paper and do not constitute a limitation on the technical solutions in this paper.

[0057] Figure 1 This is a schematic flowchart of the method for lithium and aluminum extraction using red mud in conjunction with lithium ceramic stone in Example 1. Detailed Implementation

[0058] The technical solutions of this disclosure will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of this disclosure and should not be construed as specific limitations thereof.

[0059] Example 1

[0060] This embodiment provides a method for lithium and aluminum extraction using red mud in conjunction with lithium ceramic stone, such as... Figure 1 As shown, the method includes the following steps:

[0061] S1: Mix 500g of lithium porcelain stone ore and 250g of red mud with a crusher and crush to 200 mesh. The mass ratio of lithium porcelain stone to red mud is 1:0.5 to obtain mixed crushed material. Add the obtained mixed crushed material to a roasting furnace for primary roasting. The roasting temperature of the roasting furnace is 850℃ and the roasting time is 2h to obtain primary roasted material.

[0062] S2: Add the primary roasted material obtained in S1 to the 200-mesh red mud mixture, and then soak it in deionized water. The mass ratio of the primary roasted material to the red mud is 1:0.5, and the mass ratio of the mixture to the deionized water is 1:1 to obtain the soaked material.

[0063] S3: The soaked material of S2 is added to a vacuum furnace for secondary roasting. The vacuum furnace roasting temperature is 950℃ and the roasting time is 4h to obtain the secondary roasted material.

[0064] S4: Mix the leaching agent with the secondary roasted material of S3 at a liquid-solid ratio of 3mL:1g. The leaching agent is sulfuric acid with a concentration of 8mol / L. Perform a single leaching. After solid-liquid separation, obtain the leaching solution and leaching residue.

[0065] S5: Remove impurities from the leachate obtained in S4 to obtain qualified lithium liquid product and metallurgical slag;

[0066] S6: Mix the leaching agent with the leaching residue obtained in S4 at a liquid-solid ratio of 3 mL: 1 g. Use sulfuric acid as the leaching agent with a concentration of 8 mol / L for secondary leaching. After solid-liquid separation, aluminum solution and silicon slag are obtained.

[0067] Example 2

[0068] This embodiment provides a method for lithium and aluminum extraction using red mud in conjunction with lithium ceramic stone, the method comprising the following steps:

[0069] S1: Mix 500g of lithium porcelain stone ore and 100g of red mud with a crusher and crush to 200 mesh. The mass ratio of lithium porcelain stone to red mud is 1:0.2 to obtain mixed crushed material. Add the obtained mixed crushed material to a roasting furnace for primary roasting. The roasting temperature of the roasting furnace is 950℃ and the roasting time is 3h to obtain primary roasted material.

[0070] S2: Add the primary roasted material obtained in S1 to the 200-mesh red mud mixture, and then soak it in deionized water. The mass ratio of the primary roasted material to the red mud is 1:0.6, and the mass ratio of the mixture to the deionized water is 1:0.8 to obtain the soaked material.

[0071] S3: Add the soaked material from S2 to a vacuum furnace for secondary roasting. The vacuum furnace roasting temperature is 1000℃ and the roasting time is 5h to obtain the secondary roasted material.

[0072] S4: Mix the leaching agent with the secondary roasted material of S3 at a liquid-solid ratio of 3mL:1g. The leaching agent is sulfuric acid with a concentration of 12mol / L. Perform a single leaching. After solid-liquid separation, obtain the leaching solution and leaching residue.

[0073] S5: Remove impurities from the leachate obtained in S4 to obtain qualified lithium liquid product and metallurgical slag;

[0074] S6: Mix the leaching agent with the leaching residue obtained in S4 at a liquid-solid ratio of 3 mL: 1 g. Use sulfuric acid as the leaching agent with a concentration of 12 mol / L for secondary leaching. After solid-liquid separation, aluminum solution and silicon slag are obtained.

[0075] Example 3

[0076] This embodiment provides a method for lithium and aluminum extraction using red mud in conjunction with lithium ceramic stone, the method comprising the following steps:

[0077] S1: 500g of lithium porcelain stone ore and 400g of red mud are mixed and crushed to 200 mesh using a crusher. The mass ratio of lithium porcelain stone to red mud is 1:0.8 to obtain mixed crushed material. The mixed crushed material is added to a roasting furnace for primary roasting. The roasting temperature of the roasting furnace is 750℃ and the roasting time is 1h to obtain primary roasted material.

[0078] S2: Add the primary roasted material obtained in S1 to the 200-mesh red mud mixture, and then soak it in deionized water. The mass ratio of the primary roasted material to the red mud is 1:0.5, and the mass ratio of the mixture to the deionized water is 1:0.8 to obtain the soaked material.

[0079] S3: The soaking material of S2 is added to a vacuum furnace for secondary roasting. The vacuum furnace roasting temperature is 850℃ and the roasting time is 2h to obtain the secondary roasted material.

[0080] S4: Mix the leaching agent with the secondary roasted material of S3 at a liquid-solid ratio of 3mL:1g. The leaching agent is sulfuric acid with a concentration of 6mol / L. Perform a single leaching. After solid-liquid separation, obtain the leaching solution and leaching residue.

[0081] S5: Remove impurities from the leachate obtained in S4 to obtain qualified lithium liquid product and metallurgical slag;

[0082] S6: Mix the leaching agent with the leaching residue obtained in S4 at a liquid-solid ratio of 3 mL: 1 g. Use sulfuric acid as the leaching agent with a concentration of 6 mol / L for secondary leaching. After solid-liquid separation, aluminum solution and silicon slag are obtained.

[0083] Example 4

[0084] This embodiment provides a method for lithium and aluminum extraction using red mud in conjunction with lithium ceramic stone, the method comprising the following steps:

[0085] S1: Mix 500g of lithium porcelain stone ore and 250g of red mud with a crusher and crush to 200 mesh. The mass ratio of lithium porcelain stone to red mud is 1:0.5 to obtain mixed crushed material. Add the obtained mixed crushed material to a roasting furnace for primary roasting. The roasting temperature of the roasting furnace is 850℃ and the roasting time is 1h to obtain primary roasted material.

[0086] S2: Add the primary roasted material obtained in S1 to the 200-mesh red mud mixture, and then soak it in deionized water. The mass ratio of the primary roasted material to the red mud is 1:0.5, and the mass ratio of the mixture to the deionized water is 1:0.8 to obtain the soaked material.

[0087] S3: The soaking material of S2 is added to a vacuum furnace for secondary roasting. The vacuum furnace roasting temperature is 850℃ and the roasting time is 2h to obtain the secondary roasted material.

[0088] S4: Mix the leaching agent with the secondary roasted material of S3 at a liquid-solid ratio of 3mL:1g. The leaching agent is hydrochloric acid with a concentration of 6mol / L. Perform a single leaching. After solid-liquid separation, obtain the leaching solution and leaching residue.

[0089] S5: Remove impurities from the leachate obtained in S4 to obtain qualified lithium liquid product and metallurgical slag;

[0090] S6: Mix the leaching agent with the leaching residue obtained in S4 at a liquid-solid ratio of 3 mL: 1 g. Use hydrochloric acid as the leaching agent with a concentration of 6 mol / L for secondary leaching. After solid-liquid separation, aluminum solution and silicon slag are obtained.

[0091] Example 5

[0092] This embodiment provides a method for lithium and aluminum extraction using red mud in conjunction with lithium ceramic stone, the method comprising the following steps:

[0093] S1: Mix 500g of lithium porcelain stone ore and 250g of red mud with a crusher and crush to 200 mesh. The mass ratio of lithium porcelain stone to red mud is 1:0.5 to obtain mixed crushed material. Add the obtained mixed crushed material to a roasting furnace for primary roasting. The roasting temperature of the roasting furnace is 850℃ and the roasting time is 1h to obtain primary roasted material.

[0094] S2: Add the primary roasted material obtained in S1 to the 200-mesh red mud mixture, and then soak it in deionized water. The mass ratio of the primary roasted material to the red mud is 1:0.5, and the mass ratio of the mixture to the deionized water is 1:0.8 to obtain the soaked material.

[0095] S3: The soaking material of S2 is added to a vacuum furnace for secondary roasting. The vacuum furnace roasting temperature is 850℃ and the roasting time is 2h to obtain the secondary roasted material.

[0096] S4: Mix the leaching agent with the secondary roasted material of S3 at a liquid-solid ratio of 3mL:1g. Use pure water as the leaching agent and perform a single leaching. After solid-liquid separation, obtain the leaching solution and leaching residue.

[0097] S5: Remove impurities from the leachate obtained in S4 to obtain qualified lithium liquid product and metallurgical slag;

[0098] S6: Mix the leaching agent with the leaching residue obtained in S4 at a liquid-solid ratio of 3 mL: 1 g. Use hydrochloric acid as the leaching agent with a concentration of 6 mol / L for secondary leaching. After solid-liquid separation, aluminum solution and silicon slag are obtained.

[0099] Example 6

[0100] This embodiment provides a method for extracting lithium and aluminum using red mud in conjunction with lithium ceramic stone. The method is exactly the same as in Embodiment 1 except that in step S1, the amount of red mud is adjusted from 250g to 150g, so that the mass ratio of lithium ceramic stone to red mud changes from 1:0.5 to 1:0.3.

[0101] Example 7

[0102] This embodiment provides a method for extracting lithium and aluminum using red mud in conjunction with lithium ceramic stone. The method is exactly the same as in Embodiment 1, except that in step S1, the amount of red mud is adjusted from 250g to 425g, so that the mass ratio of lithium ceramic stone to red mud changes from 1:0.5 to 1:0.85.

[0103] Example 8

[0104] This embodiment provides a method for extracting lithium and aluminum using red mud in conjunction with lithium ceramic stone. The method is exactly the same as that in Embodiment 1, except that the temperature of the first roasting is adjusted from 850°C to 700°C in step S1.

[0105] Example 9

[0106] This embodiment provides a method for extracting lithium and aluminum using red mud in conjunction with lithium ceramic stone. The method is exactly the same as that in Embodiment 1, except that the temperature of the first roasting is adjusted from 850°C to 1000°C in step S1.

[0107] Example 10

[0108] This embodiment provides a method for lithium-aluminum extraction using red mud in conjunction with lithium ceramic stone. Except for adjusting the amount of red mud in step S2 so that the mass ratio of primary roasting material to red mud changes from 1:0.5 to 1:0.15, the other conditions are exactly the same as in Embodiment 1.

[0109] Example 11

[0110] This embodiment provides a method for lithium-aluminum extraction using red mud in conjunction with lithium ceramic stone. Except for adjusting the amount of red mud in step S2 so that the mass ratio of primary roasting material to red mud changes from 1:0.5 to 1:0.85, the other conditions are exactly the same as in Embodiment 1.

[0111] Example 12

[0112] This embodiment provides a method for extracting lithium and aluminum using red mud in conjunction with lithium ceramic stone. The method is exactly the same as that in Embodiment 1, except that the temperature of the secondary roasting is adjusted from 950°C to 800°C in step S3.

[0113] Example 13

[0114] This embodiment provides a method for extracting lithium and aluminum using red mud in conjunction with lithium ceramic stone. The method is exactly the same as that in Embodiment 1, except that the temperature of the secondary roasting is adjusted from 950°C to 1050°C in step S3.

[0115] Example 14

[0116] This embodiment provides a method for extracting lithium and aluminum using red mud in conjunction with lithium ceramic stone. The secondary roasting in step S3 of the method is carried out in a roasting furnace, not in a vacuum furnace, that is, without applying a vacuum environment. Apart from this, the other conditions are exactly the same as in embodiment 1.

[0117] Comparative Example 1

[0118] This comparative example provides a method for lithium-aluminum extraction using lithium ceramic stone. The method does not use red mud in step S1 and uses pure water leaching in step S6. The method includes the following steps:

[0119] S1: Crush 500g of lithium porcelain stone ore to 200 mesh using a crusher to obtain crushed material; add the crushed material to a roasting furnace for primary roasting at a roasting temperature of 850℃ for 2 hours to obtain primary roasted material.

[0120] S2: Add the primary roasted material obtained in S1 to the 200-mesh red mud mixture, and then soak it in deionized water. The mass ratio of the primary roasted material to the red mud is 1:0.5, and the mass ratio of the mixture to the deionized water is 1:0.8 to obtain the soaked material.

[0121] S3: The soaked material of S2 is added to a vacuum furnace for secondary roasting. The vacuum furnace roasting temperature is 950℃ and the roasting time is 4h to obtain the secondary roasted material.

[0122] S4: Mix the leaching agent with the secondary roasted material of S3 at a liquid-solid ratio of 3mL:1g. The leaching agent is hydrochloric acid with a concentration of 8mol / L. Perform a single leaching. After solid-liquid separation, obtain the leaching solution and leaching residue.

[0123] S5: Remove impurities from the leachate obtained in S4 to obtain lithium liquid product and metallurgical slag;

[0124] S6: Mix the leaching agent with the leaching residue obtained in S4 at a liquid-solid ratio of 3mL:1g. Use pure water as the leaching agent and perform a second leaching. After solid-liquid separation, aluminum solution and silicon slag are obtained.

[0125] Comparative Example 2

[0126] This comparative example provides a method for lithium-aluminum extraction using lithium ceramic stone, wherein red mud is not used in step S2, i.e., step S2 is as follows:

[0127] The primary calcined material obtained from S1 was soaked in deionized water at a mass ratio of 1:1 to the primary calcined material and deionized water to obtain the soaked material.

[0128] Apart from this, all other conditions are exactly the same as in Example 1.

[0129] Comparative Example 3

[0130] This comparative example provides a method for lithium-aluminum extraction using lithium ceramic stone, wherein red mud is not used in step S1, i.e., step S1 is as follows:

[0131] 500g of lithium porcelain stone ore was crushed to 200 mesh using a crusher to obtain crushed material; the crushed material was added to a roasting furnace for primary roasting at a roasting temperature of 850℃ for 2 hours to obtain primary roasted material.

[0132] Apart from this, all other conditions are exactly the same as in Example 1.

[0133] Comparative Example 4

[0134] This comparative example provides a method for extracting lithium and aluminum using lithium ceramic stone. In step S2, the method does not use deionized water for soaking. Instead, the primary roasted material obtained in S1 is directly added to 200-mesh red mud at a mass ratio of 1:0.5 and mixed. The resulting mixture is then directly roasted again in S3.

[0135] Apart from this, all other conditions are exactly the same as in Example 1.

[0136] Comparative Example 5

[0137] This comparative example provides a method for extracting lithium aluminum using lithium ceramic stone. In step S1, the method does not involve a single roasting. Instead, the resulting mixed crushed material is directly mixed with 200-mesh red mud in step S2, and the mass ratio of the mixed crushed material to the red mud is controlled to be 1:0.5. Then, it is soaked in deionized water.

[0138] Apart from this, all other conditions are exactly the same as in Example 1.

[0139] Comparative Example 6

[0140] This comparative example provides a method for lithium aluminum extraction using lithium ceramic stone. In step S3, the method does not perform secondary roasting, but dries the soaking material from S2 at 100-120°C, and the resulting dried material is directly leached once in step S4.

[0141] Apart from this, all other conditions are exactly the same as in Example 1.

[0142] The lithium porcelain stone, red mud, leaching residue, leachate, lithium liquid product, and aluminum solution disclosed herein were all tested using an atomic absorption spectrophotometer according to the national standard GB / T 15337-2008. The lithium content in the lithium porcelain stone used in the examples and comparative examples was found to be 0.56 wt%, and the aluminum content in the red mud was 15 wt%. The lithium-aluminum leaching rate was calculated using the following formula:

[0143] Lithium leaching rate = (volume of lithium-containing leachate * lithium concentration in leachate) / (mass of lithium ceramic stone * percentage of lithium in lithium ceramic stone); lithium-containing leachate is the lithium liquid product mentioned above;

[0144] Aluminum leaching rate = (volume of aluminum-containing leachate * aluminum concentration in leachate) / ((mass of red mud in mixed crushed material + mass of red mud added to the mixture before leaching) * percentage of aluminum content in red mud); the aluminum-containing leachate is the aluminum solution.

[0145] The results are recorded in Tables 1 and 2.

[0146] Table 1 Results of a single leaching step

[0147]

[0148]

[0149] Table 2 Results of secondary leaching

[0150]

[0151] As can be seen from Tables 1 and 2:

[0152] The method disclosed herein can alter the crystal structure of lithium porcelain stone ore under high temperatures during primary and secondary roasting, causing the ionic bonds to break and Li... + It readily substitutes for metal ions such as Fe, Na, and K, thereby increasing the final leaching rate of lithium. A comparison of Examples 1, 2, and 3 shows that the optimal leaching results are achieved when the mass ratio of lithium ceramic stone to red mud is 1:0.5, the mass ratio of primary roasted material to red mud is 1:0.5, and an 8 mol / L sulfuric acid solution is used, resulting in a maximum lithium leaching rate of 98.74% and an aluminum leaching rate of 99.16%. Example 4 uses hydrochloric acid as the leaching agent, achieving a lithium leaching rate of 87.60% and an aluminum leaching rate of 86.93%.

[0153] In Comparative Example 1, no red mud was added during crushing, and pure water was used for the secondary leaching. Combined with Example 5, leaching with pure water proved difficult for aluminum, while lithium could be leached effectively with pure water. In Comparative Example 2, no red mud was added to the primary roasted material for soaking, resulting in a lower leaching rate. The lithium leaching rate was only 77.38%, while the aluminum leaching rate was 81.81%. This indicates that the ionic bonds were not completely broken during the primary roasting, leading to the lower leaching rate.

[0154] Comparing Example 1 with Examples 6 and 7, it was found that: if the amount of red mud added in the first roasting was too small, the leaching rate would be low and the reaction would be incomplete; if the amount of red mud added was too large, the material would clump together severely, making subsequent leaching difficult and affecting the leaching rate.

[0155] Comparing Example 1 with Examples 8 and 9, it was found that the primary roasting temperature has a significant impact on the leaching rate of the materials. At low temperatures, the leaching rates of Li and Al are only about 87%, while high temperatures have little effect on the leaching rate.

[0156] Comparing Example 1 with Examples 10 and 11, it was found that: adding too little red mud in vacuum furnace roasting leads to insufficient reaction, with Li and Al leaching rates of only about 85%; adding too much red mud results in severe material agglomeration, making subsequent leaching difficult and affecting the leaching rate.

[0157] Comparing Example 1 with Examples 12 and 13, it was found that: high vacuum calcination temperature does not have a significant effect on the leaching rate of Li and Al, while low temperature leads to a decrease in the leaching rate;

[0158] Comparing Example 1 with Example 14, it was found that the leaching rate decreased sharply, with the leaching rates of Li and Al being around 85%, indicating that the vacuum environment promotes ion exchange.

[0159] Comparing Example 1 with Comparative Examples 3-6, it was found that: without adding red mud during the first roasting, without roasting in a roasting furnace, and without roasting in a vacuum furnace, the leaching rate will directly decrease, with the leaching rates of Li and Al being only about 60%. The effect of not soaking is not very obvious, with the leaching rate of Li being 88.74% and the leaching rate of Al being 92.37%.

Claims

1. A method for lithium and aluminum extraction using red mud in conjunction with lithium ceramic stone, comprising the following steps: S1: Lithium ceramic stone and red mud are mixed and then roasted once to obtain a first-roasted material; the mass ratio of lithium ceramic stone to red mud is 1:(0.2~0.8); the temperature of the first roasting is 750~950℃; S2: The primary roasted material is mixed with red mud and soaked to obtain soaked material; the mass ratio of the primary roasted material to the red mud is 1:(0.2~0.8); the soaking solution used for soaking includes water; S3: The soaked material is subjected to secondary roasting to obtain secondary roasted material; the secondary roasting is carried out under vacuum; the temperature of the secondary roasting is 850~1000℃. S4: Perform a first leaching of the secondary roasted material to obtain leachate and leachate residue; S5: Remove impurities from the leachate to obtain metallurgical slag and lithium liquid products; S6: The leaching residue is leached a second time to obtain silicon slag and aluminum solution; in, Steps S5 and S6 are not sequential; and the first leaching in step S4 and the second leaching in step S6 involve mixing the secondary roasted material and the leaching residue with the leaching agent respectively, and then performing solid-liquid separation after leaching; the leaching agent for the first leaching includes any one or a combination of at least two of water, hydrochloric acid solution or sulfuric acid solution; the leaching agent for the second leaching includes hydrochloric acid solution and / or sulfuric acid solution.

2. The method according to claim 1, wherein, In step S1, the lithium ceramic stone and red mud are first mixed and crushed, and then roasted once.

3. The method according to claim 2, wherein, After the mixture is crushed, the particle size of both the lithium ceramic stone and the red mud is 150-300 mesh.

4. The method according to claim 3, wherein, After the mixture is crushed, the particle size of both the lithium ceramic stone and the red mud is 200-250 mesh.

5. The method according to claim 1, wherein, The mass ratio of lithium ceramic stone to red mud in step S1 is 1:(0.4~0.6).

6. The method according to claim 1, wherein, The temperature of the first roasting in step S1 is 800~850℃.

7. The method according to claim 1, wherein, The roasting time in step S1 is 1 to 3 hours.

8. The method according to claim 7, wherein, The roasting time in step S1 is 1.5~2.5h.

9. The method according to claim 1, wherein, The red mud mentioned in step S2 is red mud with a particle size of 150~300 mesh after crushing.

10. The method according to claim 9, wherein, The red mud mentioned in step S2 has a particle size of 200-250 mesh after crushing.

11. The method according to claim 1, wherein, The mass ratio of the primary roasting material to the red mud in step S2 is 1:(0.4~0.6).

12. The method according to claim 1, wherein, The mass ratio of the total mass of the primary roasting material and the red mud mixed in step S2 to the mass of water is (0.8~1.5):

1.

13. The method according to claim 12, wherein, The mass ratio of the total mass of the primary roasting material and the red mud mixed in step S2 to the mass of water is (0.8~1):

1.

14. The method according to claim 1, wherein, The temperature for the secondary roasting is 850~950℃.

15. The method according to claim 1, wherein, The secondary roasting time is 2-5 hours.

16. The method according to claim 15, wherein, The secondary roasting time is 3 to 4.5 hours.

17. The method according to claim 1, wherein, The leaching agent in step S4 is a sulfuric acid solution.

18. The method according to claim 1, wherein, When the leaching agent includes hydrochloric acid solution and / or sulfuric acid solution, the concentration of the leaching agent is 6~12 mol / L.

19. The method according to claim 18, wherein, When the leaching agent includes hydrochloric acid solution and / or sulfuric acid solution, the concentration of the leaching agent is 8~10 mol / L.

20. The method according to claim 1, wherein, In the primary leaching and the secondary leaching, the liquid-to-solid ratio of the leaching agent to the secondary roasted material and the leaching residue is (3~5) mL:1g.

21. The method according to claim 20, wherein, In the primary leaching and the secondary leaching, the liquid-solid ratio of the leaching agent to the secondary roasted material and the leaching residue is 3 mL: 1 g, respectively.

22. The method according to claim 1, wherein, The method includes the following steps: S1: Lithium ceramic stone and red mud are mixed and crushed at a mass ratio of 1:(0.4~0.6) to obtain mixed crushed material, wherein the particle size of lithium ceramic stone and red mud is 200~250 mesh. The mixed crushed material is calcined at 800~850℃ for 1.5~2.5h to obtain calcined material. S2: Take red mud with a particle size of 200~250 mesh after crushing, mix the primary roasting material with the red mud at a mass ratio of 1:(0.4~0.6), and soak it in water. Control the mass ratio of the total mass of the primary roasting material and the red mud to the mass of water to be (0.8~1):1 to obtain the soaked material; S3: The soaked material is subjected to secondary calcination under vacuum at 850~950℃ for 3~4.5h to obtain the secondary calcined material; S4: Mix the secondary roasted material with a leaching agent, wherein the leaching agent includes water, or any one or a combination of at least two of the following: a hydrochloric acid solution with a concentration of 8-10 mol / L or a sulfuric acid solution with a concentration of 8-10 mol / L. Control the liquid-solid ratio of the leaching agent to the secondary roasted material to be (3-5) mL: 1 g. Perform a single leaching on the secondary roasted material. After solid-liquid separation, obtain the leaching solution and the leaching residue. S5: Remove impurities from the leachate to obtain metallurgical slag and lithium liquid products; S6: Mix the leaching residue with the leaching agent, wherein the leaching agent includes a hydrochloric acid solution with a concentration of 8~10 mol / L and / or a sulfuric acid solution with a concentration of 8~10 mol / L, and control the liquid-solid ratio of the leaching agent to the leaching residue to be (3~5) mL:1g, and perform secondary leaching on the leaching residue. After solid-liquid separation, silicon slag and aluminum solution are obtained. Steps S5 and S6 are not in any particular order.

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