A method for extracting lithium from aluminum-based lithium-rich ore

Abstract

The present application relates to the technical field of lithium ore extraction, and in particular to a method for extracting lithium from aluminum-based lithium-rich ore; the lithium extraction method comprises: mixing a lithium extraction agent and aluminum-based lithium-rich ore particles to obtain a first mixed material; heating and stirring the first mixed material to perform a double decomposition lithium extraction reaction to obtain a second mixed material; and performing solid-liquid separation on the second mixed material to obtain a lithium-rich solution; wherein the lithium extraction agent is a compound containing calcium element; the method can achieve the dual effects of efficiently extracting lithium from aluminum-based lithium concentrate and synergistically purifying carbonate impurity ions, thereby achieving efficient, low-energy and simple extraction of lithium.

Description

Technical Field

[0001] The present application relates to the technical field of lithium ore extraction, and in particular to a method for extracting lithium from aluminum-based lithium-rich ore. Background Art

[0002] Lithium is a key strategic metal and a strategic mineral resource for every country. Therefore, it holds significant strategic importance for the national economy and national defense and military development. However, China's dependence on foreign raw materials for lithium production exceeds 70%, making the secure supply of lithium resources a significant constraint on the development of China's new energy industry. Lithium carbonate, the fundamental raw material for the production of secondary lithium salts and lithium metal, is the most fundamental and important product in the lithium industry. Currently, lithium carbonate is widely used in numerous fields, including electronic materials, chemistry, medicine, industrial ceramics, and metallurgy. However, with the rapid development of high-tech industries such as information technology, electric vehicles, and green energy, the market demand for lithium and its compounds is surging, and supply is currently outstripping supply, keeping prices high. Currently, high-quality lithium ore resources are scarce in China. The difficulty in separating magnesium from lithium in high-magnesium brines in domestic salt lakes, coupled with limited capacity expansion by international lithium giants, has led to insufficient lithium resources. Therefore, the development of lithium resources through multiple channels is the future trend of the lithium extraction industry.

[0003] Domestic bauxite is rich in associated lithium resources. High-lithium bauxite contains greater than 0.1% Li₂O. In the Bayer process for alumina production, approximately 80% of the lithium enters the solution during the Bayer process, ultimately ending up in the alumina product. Therefore, alumina produced from this type of bauxite has a high lithium content. Since alumina is a raw material for aluminum electrolysis, long-term use of high-lithium alumina as an electrolyte, when the lithium fluoride content exceeds 5%, can severely impact the electrolysis process, leading to reduced electrolysis temperature, deterioration of furnace regularity, decreased electrolysis stability, reduced current efficiency, and increased energy consumption. Furthermore, domestic alumina plants generally contain high levels of Li₂O. If the Li₂O content of alumina is estimated at 0.1% and annual alumina production is estimated at 12 million tons, the annual removal of Li₂CO₃ from metallurgical-grade alumina would amount to 63,428 tons, resulting in a significant waste of lithium resources. Therefore, efficient recycling and utilization of lithium resources in the alumina production process will not only help improve the quality of alumina products and eliminate the adverse effects on downstream aluminum electrolysis, but also open up new ways for the economic and efficient utilization of low-grade lithium-rich bauxite, and is also of great significance to the strategic security of lithium resources.

[0004] Industrial methods for producing lithium salts fall into two main categories: one involves extracting and utilizing other valuable metal minerals from lithium-containing brines to enrich the lithium in the brine, ultimately yielding lithium salt products such as Li2CO3 or Li2SO4·H2O. However, due to the low magnesium-to-lithium ratio of most domestic salt lake brines, development is challenging, and industrial implementation of lithium extraction from brines is difficult. The other method involves pyrometallurgical or hydrometallurgical treatment of the primary lithium-containing ores—spodumene and lepidolite—to destroy their original gangue structure, dissolving the Li2O contained therein as soluble lithium salts, resulting in lithium salts such as Li2SO4 and other forms. Lithium extraction from spodumene is currently the most widely used method due to its advantages, such as low material throughput, high production efficiency, low energy consumption, and high lithium recovery rate. Currently, the main methods for extracting lithium from spodumene are the sulfuric acid method and the lime method. The lime method has been less used due to its high energy consumption, low recovery rate, and high production costs. The sulfuric acid method, on the other hand, consumes large amounts of sulfuric acid, resulting in high extraction temperatures, low efficiency, high energy consumption, a long industrial process, high equipment requirements, and environmental pollution. Therefore, providing a method for extracting lithium from aluminum-based lithium-rich ores that achieves efficient, low-energy, and simple lithium extraction is a pressing technical challenge. Summary of the Invention

[0005] The present application provides a method for extracting lithium from aluminum-based lithium-rich ore to solve the technical problems in the prior art of extracting lithium from spodumene using the sulfuric acid method, such as high extraction temperature, low efficiency, high energy consumption, long industrial process, high equipment requirements, and environmental pollution.

[0006] In a first aspect, the present application provides a method for extracting lithium from an aluminum-based lithium-rich ore, the method comprising:

[0007] mixing a lithium extraction agent and aluminum-based lithium-rich ore particles to obtain a first mixed material;

[0008] heating and stirring the first mixed material to perform a double decomposition reaction to extract lithium, thereby obtaining a second mixed material;

[0009] performing solid-liquid separation on the second mixed material to obtain a lithium-rich solution;

[0010] Wherein, the lithium extracting agent is a compound containing calcium element.

[0011] Optionally, the heating and stirring temperature is 50° C. to 150° C., and the heating and stirring time is 0.5 h to 3 h.

[0012] Optionally, the compound containing calcium element includes calcium salt.

[0013] Optionally, the lithium-extracting agent includes at least one of calcium acetate, calcium chloride, calcium nitrate, calcium bicarbonate, calcium bisulfate, calcium iodide and calcium bromide.

[0014] Optionally, the amounts of calcium ions and anions in the first mixed material are the same.

[0015] Optionally, the liquid-to-solid ratio of the first mixed material is 1-15.

[0016] Optionally, the particle size of the aluminum-based lithium-rich ore particles is less than 150 mesh.

[0017] Optionally, the lithium extraction method further comprises:

[0018] The aluminum-based lithium-rich ore coarse particles are dried and then ground to obtain aluminum-based lithium-rich ore particles.

[0019] Optionally, the drying temperature is 100°C to 110°C.

[0020] Optionally, the drying time is 2 hours to 4 hours.

[0021] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0022] The present invention provides a method for extracting lithium from aluminum-based lithium-rich ore, which uses a compound containing calcium as a lithium-extracting agent. Since the lithium in the aluminum-based lithium-rich ore will be converted into Li2Al4(CO3)OH in the solution, 12 3H2O, and the calcium ions released by the lithium extractor will react with Li2Al4(CO3)OH 12 ·3H2O reacts, thereby making Li + At the same time, carbonate ions also enter the solution and react with calcium ions to precipitate, synergistically removing carbonate ions from the solution, thereby achieving the dual effects of efficiently extracting lithium from aluminum-based lithium concentrate and synergistically purifying carbonate impurity ions. Therefore, efficient, low-energy and simple extraction of lithium can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0025] Figure 1A schematic flow chart of a method for extracting lithium from an aluminum-based lithium-rich ore provided in an embodiment of the present application;

[0026] Figure 2 A detailed flow chart of a method for extracting lithium from an aluminum-based lithium-rich ore provided in an embodiment of the present application. DETAILED DESCRIPTION

[0027] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0028] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0029] like Figure 1 As shown, the embodiment of the present application provides a method for extracting lithium from an aluminum-based lithium-rich ore, the lithium extraction method comprising:

[0030] S1. Mixing a lithium extraction agent and aluminum-based lithium-rich ore particles to obtain a first mixed material;

[0031] S2. The first mixed material is heated and stirred to perform a double decomposition reaction to extract lithium to obtain a second mixed material;

[0032] S3. The second mixed material is subjected to solid-liquid separation to obtain a lithium-rich solution;

[0033] Wherein, the lithium extracting agent is a compound containing calcium element.

[0034] In the embodiment of the present application, since the aluminum in the aluminum-based lithium-rich ore hardly undergoes leaching reaction in the calcium ion solution, the sodium and potassium ions in the leachate have no effect on the subsequent lithium extraction process, so selective lithium extraction can be achieved through compounds containing calcium elements.

[0035] The lithium extraction agent can exist in the form of a solid reagent or a liquid reagent. For practical needs, such as convenience of storage and transportation, a solvent, such as water, can be adaptively added to the lithium extraction agent.

[0036] In some optional embodiments, the temperature of the heating and stirring is 50° C. to 150° C., and the time of the heating and stirring is 0.5 h to 3 h.

[0037] In the embodiment of the present application, the specific temperature and specific time of heating and stirring are controlled so that the lithium in the aluminum-based lithium-rich ore particles and the lithium extracting agent undergo a double decomposition reaction, so that the lithium is converted into Li2Al4(CO3)OH 12 ·3H2O exists, while calcium salt and Li2Al4(CO3)OH 12 ·3H2O reacts, thereby Li + Enter the solution to achieve efficient and selective extraction of lithium from aluminum-based lithium-rich ore. At the same time, carbonate also enters the solution, and calcium ions react with carbonate to precipitate to achieve Li + The solution is purified by reaction, and the content of impurities such as carbonate and aluminum ions in the solution after leaching is low, thereby obtaining a lithium-rich solution.

[0038] The temperature of the heating and stirring can be 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C.

[0039] The heating and stirring time can be 0.5 h, 1 h, 2 h, or 3 h.

[0040] In some optional embodiments, the compound containing calcium element includes a calcium salt.

[0041] In some optional embodiments, the lithium-extracting agent includes at least one of calcium acetate, calcium chloride, calcium nitrate, calcium bicarbonate, calcium bisulfate, calcium iodide, and calcium bromide.

[0042] In the embodiment of the present application, the specific composition of the compound containing calcium element is limited. Since calcium salt refers to an ionic compound composed of calcium ions and acid radical ions, which can generally be obtained by the reaction of calcium with acid, it can make Li + Better to go into solution.

[0043] In some optional embodiments, the amounts of calcium ions and anionic substances in the first mixed material are the same.

[0044] In the embodiment of the present application, the double decomposition reaction rate can be controlled by controlling the amount of calcium ions and anions in the first mixed material; if the amount of calcium ions is too low, the lithium leaching rate will be affected, and if the amount of calcium ions is too high, the solution viscosity will be increased, thereby reducing the lithium leaching rate.

[0045] In some optional embodiments, the liquid-to-solid ratio of the first mixed material is 1-15.

[0046] In the embodiment of the present application, controlling the specific solid-liquid ratio in the first mixed material can enable the double decomposition reaction to proceed smoothly; when the solid-liquid ratio is too large, the lithium concentration in the leachate is low, and when the solid-liquid ratio is too small, the reaction rate is affected and the lithium extraction efficiency is reduced.

[0047] The solid-liquid ratio can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, or 15.

[0048] In some optional embodiments, the particle size of the aluminum-based lithium-rich ore particles is less than 150 mesh.

[0049] In the embodiments of the present application, controlling the specific particle size of the aluminum-based lithium-rich ore particles can allow the lithium in the aluminum-based lithium-rich ore to quickly enter the solution, thereby improving the lithium leaching rate.

[0050] In some optional embodiments, the lithium extraction method further comprises:

[0051] S101. Dry the aluminum-based lithium-rich ore coarse particles, and then grind them to obtain aluminum-based lithium-rich ore particles.

[0052] In the embodiment of the present application, by drying and then grinding the aluminum-based lithium-rich ore coarse particles, the drying can be used to quickly lose moisture in the aluminum-based lithium-rich ore coarse particles, thereby improving the roughness of the aluminum-based lithium-rich ore coarse particles. During the grinding stage, the rough surface of the internal particles can be used to achieve self-grinding, thereby obtaining aluminum-based lithium-rich ore particles that meet the expected particle size.

[0053] In some optional embodiments, the drying temperature is 100°C to 110°C.

[0054] In some optional embodiments, the drying time is 2 hours to 4 hours.

[0055] In the embodiments of the present application, the specific temperature and specific time of drying are controlled to quickly lose moisture from the aluminum-based lithium-rich ore coarse particles, thereby improving the roughness of the aluminum-based lithium-rich ore coarse particles. During the grinding stage, the rough surfaces of the internal particles can be used to achieve self-grinding, thereby obtaining aluminum-based lithium-rich ore particles that meet the expected particle size.

[0056] The present application will be further described below in conjunction with specific examples. It should be understood that these examples are intended to illustrate the present application only and are not intended to limit the scope of the present application. The experimental methods in the following examples where specific conditions are not specified are usually measured in accordance with national standards. If there are no corresponding national standards, then the methods are carried out in accordance with general international standards, conventional conditions, or according to the conditions recommended by the manufacturer.

[0057] Example 1

[0058] A method for extracting lithium from an aluminum-based lithium-rich ore, the method comprising:

[0059] S101. The aluminum-based lithium-rich ore coarse particles are dried and then ground to obtain aluminum-based lithium-rich ore particles;

[0060] mixing a lithium extraction agent and aluminum-based lithium-rich ore particles to obtain a first mixed material;

[0061] S1. The first mixed material is heated and stirred to perform a double decomposition reaction to extract lithium to obtain a second mixed material;

[0062] S2. The second mixed material is subjected to solid-liquid separation, the solid is modified red mud, and the filtrate is a lithium-rich solution;

[0063] Wherein, the lithium extracting agent is calcium acetate.

[0064] The heating and stirring temperature is 50° C., and the heating and stirring time is 3 h.

[0065] The molar fraction of calcium ions in the first mixed material is 100%.

[0066] The liquid-to-solid ratio of the first mixed material is 1.

[0067] The particle size of the aluminum-based lithium-rich ore particles is less than 150 meshes.

[0068] The drying temperature is 100°C.

[0069] The drying time is 2 hours.

[0070] The lithium leaching rate in this example was 95.5%.

[0071] Example 2

[0072] Comparing Example 2 with Example 1, the difference between Example 2 and Example 1 is:

[0073] The lithium extracting agent is calcium acetate.

[0074] The heating and stirring temperature is 100° C., and the heating and stirring time is 2 h.

[0075] The liquid-to-solid ratio of the first mixed material is 5.

[0076] The drying temperature is 105°C.

[0077] The drying time is 3 hours.

[0078] The lithium leaching rate in this example was 96.1%.

[0079] Example 3

[0080] Comparing Example 3 with Example 1, the difference between Example 3 and Example 1 is:

[0081] The lithium-extracting agent includes calcium acetate.

[0082] The heating and stirring temperature is 120° C., and the heating and stirring time is 3 h.

[0083] The liquid-to-solid ratio of the first mixed material is 10.

[0084] The molar fraction of calcium ions in the first mixed material is 15%.

[0085] The drying temperature is 110°C.

[0086] The drying time is 4 hours.

[0087] The lithium leaching rate in this example was 97.5%.

[0088] Example 4

[0089] Comparing Example 4 with Example 1, the difference between Example 4 and Example 1 is:

[0090] The lithium extracting agent is calcium acetate.

[0091] The heating and stirring temperature is 150° C., and the heating and stirring time is 2 h.

[0092] The liquid-to-solid ratio of the first mixed material is 10.

[0093] The drying temperature is 110°C.

[0094] The drying time is 2 hours.

[0095] In this example, the lithium leaching rate was 98.3%.

[0096] Example 5

[0097] Comparing Example 5 with Example 1, the difference between Example 5 and Example 1 is:

[0098] The lithium extracting agent is calcium chloride.

[0099] The heating and stirring temperature is 135° C., and the heating and stirring time is 2 h.

[0100] The liquid-to-solid ratio of the first mixed material is 1.

[0101] The drying temperature is 105°C.

[0102] The drying time is 3 hours.

[0103] In this example, the lithium leaching rate was 99.2%.

[0104] Example 6

[0105] Comparing Example 6 with Example 1, the difference between Example 6 and Example 1 is:

[0106] The lithium extracting agent is calcium chloride.

[0107] The heating and stirring temperature is 50° C. to 150° C., and the heating and stirring time is 0.5 h to 3 h.

[0108] The liquid-to-solid ratio of the first mixed material is 1-15.

[0109] The drying temperature is 100°C to 110°C.

[0110] The drying time is 2 hours to 4 hours.

[0111] The lithium leaching rate in this example was 99.6%.

[0112] Example 7

[0113] Comparing Example 7 with Example 1, the difference between Example 7 and Example 1 is:

[0114] The lithium extracting agent is calcium chloride.

[0115] The heating and stirring temperature is 140° C., and the heating and stirring time is 2 h.

[0116] The liquid-to-solid ratio of the first mixed material is 10.

[0117] The drying temperature is 105°C.

[0118] The drying time is 4 hours.

[0119] The lithium leaching rate in this example was 97.8%.

[0120] Example 8

[0121] Comparing Example 8 with Example 1, the difference between Example 8 and Example 1 is:

[0122] The lithium extracting agent is calcium chloride.

[0123] The heating and stirring temperature is 150° C., and the heating and stirring time is 2 h.

[0124] The liquid-to-solid ratio of the first mixed material is 15.

[0125] The drying temperature is 100°C.

[0126] The drying time is 4 hours.

[0127] The lithium leaching rate in this example was 97.8%.

[0128] In summary, the present invention provides a method for extracting lithium from aluminum-based lithium-rich ore, which uses a compound containing calcium as a lithium-extracting agent, so that the lithium in the aluminum-based lithium-rich ore is converted into Li2Al4(CO3)OH 12 ·3H2O exists, while calcium salt and Li2Al4(CO3)OH 12 ·3H2O reacts, thereby making Li + At the same time, carbonate ions also enter the solution and react with calcium ions for precipitation, synergistically removing carbonate ions from the solution, thereby achieving the dual effects of efficient lithium extraction from aluminum-based lithium concentrate and synergistic purification of carbonate impurity ions. The content of impurities such as silicon and aluminum in the extracted solution is low, which is conducive to the subsequent preparation of high-quality lithium salts.

[0129] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be understood as a hard limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numbers within the range. For example, the description of a range from 1 to 6 should be considered to have specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which applies regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0130] In this application, unless otherwise specified, the directional words used, such as "upper" and "lower", refer specifically to the directions of the drawings in the accompanying drawings. In addition, in the description of the present application specification, the terms "including", "comprising", etc. mean "including but not limited to". In this article, relational terms such as "first" and "second" are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. Wherein A and B can be singular or plural. In this article, "at least one" refers to one or more, and "plurality" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c", or "at least one of a, b and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple.

[0131] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. A method for extracting lithium from aluminum-based lithium-rich ore, characterized in that: The lithium extraction method comprises: The aluminum-based lithium-rich ore coarse particles are dried and then ground to obtain aluminum-based lithium-rich ore particles; Add solvent water to the lithium extraction agent, mix the lithium extraction agent and aluminum-based lithium-rich ore particles to obtain a first mixed material, wherein the lithium in the aluminum-based lithium-rich ore particles is converted into Li2Al4(CO3)OH in the solution. 12 ·Exists in the form of 3H2O; heating and stirring the first mixed material to perform a double decomposition reaction to extract lithium, thereby obtaining a second mixed material; performing solid-liquid separation on the second mixed material to obtain a lithium-rich solution; Wherein, the lithium extraction agent includes at least one of calcium acetate, calcium chloride, calcium nitrate, calcium bicarbonate, calcium bisulfate, calcium iodide and calcium bromide; The heating and stirring temperature is 50°C to 100°C, and the heating and stirring time is 0.5h to 3h; The particle size of the aluminum-based lithium-rich ore particles is less than 150 meshes.

2. The lithium extraction method according to claim 1, characterized in that The liquid-to-solid ratio of the first mixed material is 1-15.

3. The lithium extraction method according to claim 1, characterized in that The drying temperature is 100°C to 110°C.

4. The lithium extraction method according to claim 1, characterized in that The drying time is 2 hours to 4 hours.

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