A lithium extraction from salt lake titanium-based adsorption material and its preparation method

Abstract

The present invention relates to a titanium-based adsorption material for extracting lithium from salt lakes and a preparation method thereof, belonging to the technical field of adsorption materials. The preparation method of the titanium-based adsorption material for extracting lithium from salt lakes comprises the following steps: mixing a titanium source and a lithium source, and then performing first magnetic field sintering to obtain a first precursor; performing second magnetic field sintering on the first precursor to obtain a second precursor; performing third magnetic field sintering on the second precursor to obtain a third precursor; adding the third precursor into an acidic solution for acidification, and then filtering and drying to obtain the titanium-based adsorption material for extracting lithium from salt lakes. The present invention adopts a three-stage magnetic field sintering method, and by controlling the condition parameters of each stage, the lithium element adsorption capacity and desorption rate of the obtained titanium-based adsorption material are significantly improved, providing an efficient and stable titanium-based adsorption material for the field of extracting lithium from salt lakes and making up for the deficiencies of the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of adsorption materials, and particularly relates to a titanium-based adsorption material for extracting lithium from salt lakes and a preparation method thereof. Background Art

[0002] With the increasing global demand for renewable energy, lithium, as a key material, has become increasingly important in battery technology and energy storage systems. However, traditional lithium extraction methods, such as the metal magnesium method or chemical method, face many challenges in terms of environment, cost, and resource utilization. Especially for extracting lithium from salt lake brines, the technical difficulty and economic cost are even more significant. Therefore, it is particularly important to develop efficient, environmentally friendly, and sustainable lithium extraction technologies.

[0003] In existing salt lake lithium extraction technologies, solvent extraction, precipitation crystallization, membrane separation, etc. each have their own advantages and disadvantages, but all have limitations to varying degrees. Although solvent extraction has certain applications in salt lake systems with a high magnesium-lithium ratio, its potential for generating three phases, corroding process equipment, and leaking solutions to pollute the environment limits its popularization and application. Although membrane separation technology is efficient and environmentally friendly, problems such as high energy consumption and unsatisfactory membrane durability also hinder its industrialization process. In contrast, adsorption methods have developed rapidly in the field of salt lake lithium extraction in recent years due to their advantages such as low cost, simple operation, environmental friendliness, high selectivity, and wide application range. The core of the adsorption method lies in selecting or designing and synthesizing an adsorption material with high-efficiency recognition ability for lithium ions, and realizing the selective separation and recovery of lithium ions through specific physical or chemical actions.

[0004] Among adsorption materials, titanium-based adsorbents have attracted much attention due to their unique properties. As a new type of lithium ion adsorbent, titanium-based materials have good cycle stability and high specific surface area, and can effectively adsorb and release lithium ions. In addition, titanium-based adsorbents also have the characteristics of controllable preparation, and can adjust their morphology and structure according to different application requirements. These advantages make titanium-based adsorbents show great application potential in the field of salt lake lithium extraction. However, existing titanium-based adsorption materials often have problems such as limited adsorption capacity and low desorption rate during the preparation process, making it difficult to meet the requirements of industrial production of salt lake lithium extraction. Summary of the Invention

[0005] To solve the above problems, the present invention provides a titanium-based adsorption material for extracting lithium from salt lakes and a preparation method thereof.

[0006] In the first aspect, the present invention provides a preparation method of a titanium-based adsorption material for extracting lithium from salt lakes, and the preparation method of the titanium-based adsorption material for extracting lithium from salt lakes includes the following steps:

[0007] Mix a titanium source and a lithium source, and then perform first magnetic field sintering to obtain a first precursor;

[0008] Subject the first precursor to a second magnetic field sintering to obtain a second precursor;

[0009] Subject the second precursor to a third magnetic field sintering to obtain a third precursor;

[0010] Add the third precursor into an acidic solution for acidification, then filter and dry to obtain the lithium extraction from salt lake titanium-based adsorbent material;

[0011] The working condition parameters of the first magnetic field sintering include: the magnetic flux coil current is 2.5 - 5 A, the temperature is 200 - 280 °C, and the time is 1 - 2 hours;

[0012] The working condition parameters of the second magnetic field sintering include: the magnetic flux coil current is 12 - 15 A, the temperature is 670 - 750 °C, and the time is 4 - 6 hours;

[0013] The working condition parameters of the third magnetic field sintering include: the magnetic flux coil current is 6 - 10 A, the temperature is 300 - 400 °C, and the time is 1 - 2 hours.

[0014] Further, the working condition parameters of the first magnetic field sintering include: the magnetic flux coil current is 4 A, the temperature is 260 °C, and the time is 1 - 2 hours.

[0015] Further, the working condition parameters of the second magnetic field sintering include: the magnetic flux coil current is 13 A, the temperature is 720 °C, and the time is 4 - 6 hours.

[0016] Further, the working condition parameters of the third magnetic field sintering include: the magnetic flux coil current is 8 A, the temperature is 380 °C, and the time is 1 - 2 hours.

[0017] Further, the molar ratio of Ti in the titanium source to Li in the lithium source is 1:(2 - 2.2).

[0018] Further, the titanium source includes at least one of titanium dioxide, metatitanic acid, titanium chloride, titanium sulfate, and tetrabutyl titanate.

[0019] Further, the lithium source includes at least one of lithium carbonate, lithium hydroxide, lithium chloride, lithium acetate, and lithium nitrate.

[0020] Further, the working condition parameters of the acidification include: the acidification temperature is 45 - 55 °C, and the acidification time is 10 - 20 hours.

[0021] Further, the acidic solution uses a hydrochloric acid solution with a molar concentration of 0.01 - 0.1 mol / L.

[0022] In a second aspect, the present invention provides a titanium-based adsorbent material for extracting lithium from salt lakes, and the titanium-based adsorbent material for extracting lithium from salt lakes is prepared by using the preparation method described in any one of the first aspect.

[0023] The above technical solutions provided by the embodiments of the present invention have at least the following advantages compared with the prior art:

[0024] The embodiments of the present invention provide a titanium-based adsorbent material for extracting lithium from salt lakes and a preparation method thereof. The present invention adopts a three-stage magnetic field sintering method. By controlling the condition parameters of each stage, the lithium element adsorption capacity and desorption rate of the obtained titanium-based adsorbent material are significantly improved, providing an efficient and stable titanium-based adsorbent material for the field of extracting lithium from salt lakes and making up for the deficiencies of the prior art. Specifically:

[0025] The first stage: Select appropriate titanium sources (such as titanium dioxide, titanate, etc.) and lithium sources (such as lithium carbonate, lithium hydroxide, etc.) for mixing, and conduct preliminary sintering under the first magnetic field sintering conditions. This step aims to promote the preliminary chemical reaction between the titanium source and the lithium source. The introduction of the magnetic field can promote the formation of a more ordered structure, initially form a precursor structure, avoid the premature formation of a dense structure that hinders subsequent reactions, and lay the foundation for the subsequent steps.

[0026] The second stage: On the basis of the first precursor, adjust the magnetic field intensity and sintering temperature for the second magnetic field sintering. The main purpose of this stage is to further optimize the crystal structure of the material, enhance the stability and specific surface area of the material. The continuous action of the magnetic field helps to refine the grains, increase the porosity and active sites of the material, and is beneficial to improving the lithium element adsorption capacity of the titanium-based adsorbent material.

[0027] The third stage: After the first two sinterings, the third magnetic field sintering stage further consolidates and optimizes the structural characteristics of the material, and at the same time fine-tunes the surface properties of the material by adjusting the sintering conditions (such as reducing the temperature, changing the magnetic field intensity), making it more conducive to the adsorption and desorption of lithium ions and improving the material stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings here are incorporated into the description and form a part of this description, showing embodiments in line with the present invention, and are used together with the description to explain the principles of the present invention.

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1Schematic flow chart of a method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes provided by an embodiment of the present invention.

[0031] Figure 2 Electron microscopy characterization diagram of the titanium-based adsorbent material for lithium extraction from salt lakes provided by Embodiment 1 of the present invention.

[0032] Figure 3 Electron microscopy characterization diagram of the titanium-based adsorbent material for lithium extraction from salt lakes provided by Comparative Example 1 of the present invention.

[0033] Figure 4 Electron microscopy characterization diagram of the titanium-based adsorbent material for lithium extraction from salt lakes provided by Comparative Example 2 of the present invention. Detailed implementation manners

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0035] Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the present invention can be obtained through market purchases or can be prepared by existing methods.

[0036] In a first aspect, the present invention provides a method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes, as Figure 1 shown, the method for preparing the titanium-based adsorbent material for lithium extraction from salt lakes includes the following steps:

[0037] Mix a titanium source and a lithium source, and then perform first magnetic field sintering to obtain a first precursor;

[0038] Perform second magnetic field sintering on the first precursor to obtain a second precursor;

[0039] Perform third magnetic field sintering on the second precursor to obtain a third precursor;

[0040] Add the third precursor to an acidic solution for acidification, and then filter and dry to obtain the titanium-based adsorbent material for lithium extraction from salt lakes;

[0041] The working condition parameters of the first magnetic field sintering include: the magnetic flux coil current is 2.5 - 5 A, the temperature is 200 - 280 °C, and the time is 1 - 2 hours;

[0042] The working condition parameters of the second magnetic field sintering include: the magnetic flux coil current is 12 - 15 A, the temperature is 670 - 750 °C, and the time is 4 - 6 hours;

[0043] The working condition parameters of the third magnetic field sintering include: the magnetic flux coil current is 6 - 10 A, the temperature is 300 - 400 °C, and the time is 1 - 2 hours.

[0044] The embodiment of the present invention provides a preparation method of a titanium - based adsorption material for lithium extraction from salt lakes. The present invention adopts a three - stage magnetic field sintering method. By controlling the condition parameters of each stage, the lithium element adsorption capacity and desorption rate of the obtained titanium - based adsorption material are significantly improved, providing an efficient and stable titanium - based adsorption material for the field of lithium extraction from salt lakes and making up for the deficiencies of the prior art. Specifically:

[0045] The first stage: Select appropriate titanium sources (such as titanium dioxide, titanate, etc.) and lithium sources (such as lithium carbonate, lithium hydroxide, etc.) for mixing, and conduct preliminary sintering under the first magnetic field sintering conditions. This step aims to promote the preliminary chemical reaction between the titanium source and the lithium source. The introduction of the magnetic field can promote the formation of a more ordered structure, initially form a precursor structure, avoid the premature formation of a dense structure that hinders subsequent reactions, and lay a foundation for the subsequent steps.

[0046] The second stage: On the basis of the first precursor, adjust the magnetic field intensity and sintering temperature for the second magnetic field sintering. The main purpose of this stage is to further optimize the crystal structure of the material, enhance the stability and specific surface area of the material. The continuous action of the magnetic field helps to refine the grains, increase the porosity and active sites of the material, which is beneficial to improving the lithium element adsorption capacity of the titanium - based adsorption material.

[0047] The third stage: After the first two sinterings, the third magnetic field sintering stage further consolidates and optimizes the structural characteristics of the material. At the same time, by adjusting the sintering conditions (such as reducing the temperature, changing the magnetic field intensity), the surface properties of the material are finely adjusted to make it more conducive to the adsorption and desorption of lithium ions and improve the material stability.

[0048] In some specific embodiments, the working condition parameters of the first magnetic field sintering include: the magnetic flux coil current is 4 A, the temperature is 260 °C, and the time is 1 - 2 hours.

[0049] In some specific embodiments, the working condition parameters of the second magnetic field sintering include: the magnetic flux coil current is 13 A, the temperature is 720 °C, and the time is 4 - 6 hours.

[0050] In some specific embodiments, the working condition parameters of the third magnetic field sintering include: the magnetic flux coil current is 8 A, the temperature is 380 °C, and the time is 1 - 2 hours.

[0051] In some specific embodiments, the molar ratio of Ti in the titanium source to Li in the lithium source is 1:(2 - 2.2), preferably 1:2.1.

[0052] In some specific embodiments, the titanium source includes at least one of titanium dioxide, metatitanic acid, titanium chloride, titanium sulfate, and tetrabutyl titanate.

[0053] In some specific embodiments, the lithium source includes at least one of lithium carbonate, lithium hydroxide, lithium chloride, lithium acetate, and lithium nitrate.

[0054] In some specific embodiments, the working condition parameters of acidification include: the acidification temperature is 45 - 55 °C, and the acidification time is 10 - 20 hours.

[0055] In some specific embodiments, the acidic solution uses a hydrochloric acid solution with a molar concentration of 0.01 - 0.1 mol / L, and a hydrochloric acid solution with a molar concentration of 0.01 mol / L is optional.

[0056] In a second aspect, based on the same inventive concept, the present invention provides a titanium-based adsorbent material for extracting lithium from salt lakes, and the titanium-based adsorbent material for extracting lithium from salt lakes is prepared by using the preparation method described in any item of the first aspect.

[0057] The titanium-based adsorbent material for extracting lithium from salt lakes provided by the present invention is realized based on the preparation method described in any item of the first aspect. Therefore, the titanium-based adsorbent material for extracting lithium from salt lakes at least has the beneficial effects of the technical solutions described in any item of the first aspect, which will not be elaborated one by one here.

[0058] It should be noted that for the component raw materials involved in the titanium-based adsorbent material for extracting lithium from salt lakes and its preparation method provided in the embodiments of the present invention, without special limitations or specific descriptions, commercially available products can be directly used or self-made by using existing publicly disclosed preparation methods; meanwhile, for the steps and parameters involved, without special limitations or specific descriptions, they can be carried out according to the processing technology of existing titanium-based adsorbent materials or directly using existing equipment, which will not be elaborated one by one in this invention document.

[0059] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. The experimental methods without specific conditions noted in the following embodiments are usually determined according to national standards. If there are no corresponding national standards, they are carried out according to general international standards, conventional conditions, or the conditions recommended by the manufacturer.

[0060] Example 1

[0061] This example provides a titanium-based adsorbent material for extracting lithium from salt lakes, and the preparation method of the titanium-based adsorbent material for extracting lithium from salt lakes includes the following steps:

[0062] Step (1): Mix the titanium source (specifically metatitanic acid) and the lithium source (specifically lithium carbonate), then add them into a magnetic field sintering furnace. Conduct the first magnetic field sintering at a magnetic flux coil current of 4 A, heating from room temperature to 260 °C at a rate of 10 °C / min for 1.5 hours, and then cool with the furnace to obtain the first precursor; wherein, the molar ratio of Ti in the titanium source to Li in the lithium source is 1:2.1;

[0063] Step (2): Conduct the second magnetic field sintering on the first precursor obtained in step (1) at a magnetic flux coil current of 13 A, heating from room temperature to 720 °C at a rate of 10 °C / min for 5 hours, and then cool with the furnace to obtain the second precursor;

[0064] Step (3): Conduct the third magnetic field sintering on the second precursor obtained in step (2) at a magnetic flux coil current of 8 A, heating from room temperature to 380 °C at a rate of 10 °C / min for 1.5 hours, and then cool with the furnace to obtain the third precursor;

[0065] Step (4): Immerse the third precursor obtained in step (3) in a 0.01 mol / L hydrochloric acid solution for acidification. The acidification temperature is 50 °C and the acidification time is 18 hours. Then filter and vacuum dry the obtained solid at 50 °C until constant weight to obtain the lithium extraction from salt lake titanium-based adsorbent material.

[0066] Example 2

[0067] This example provides a lithium extraction from salt lake titanium-based adsorbent material. The preparation method of the lithium extraction from salt lake titanium-based adsorbent material includes the following steps:

[0068] Step (1): Mix the titanium source (specifically metatitanic acid) and the lithium source (specifically lithium carbonate), then add them into a magnetic field sintering furnace. Conduct the first magnetic field sintering at a magnetic flux coil current of 2.5 A, heating from room temperature to 280 °C at a rate of 10 °C / min for 1.5 hours, and then cool with the furnace to obtain the first precursor; wherein, the molar ratio of Ti in the titanium source to Li in the lithium source is 1:2.1;

[0069] Step (2): Conduct the second magnetic field sintering on the first precursor obtained in step (1) at a magnetic flux coil current of 15 A, heating from room temperature to 670 °C at a rate of 10 °C / min for 6 hours, and then cool with the furnace to obtain the second precursor;

[0070] Step (3): Conduct the third magnetic field sintering on the second precursor obtained in step (2) at a magnetic flux coil current of 6 A, heating from room temperature to 300 °C at a rate of 10 °C / min for 1.5 hours, and then cool with the furnace to obtain the third precursor;

[0071] Step (4): Immerse the third precursor obtained in step (3) in a 0.01 mol / L hydrochloric acid solution for acidification. The acidification temperature is 50 °C and the acidification time is 18 hours. Then, filter and vacuum-dry the obtained solid at 50 °C until constant weight to obtain the lithium extraction from salt lake titanium-based adsorbent material.

[0072] Example 3

[0073] This example provides a lithium extraction from salt lake titanium-based adsorbent material. The preparation method of the lithium extraction from salt lake titanium-based adsorbent material includes the following steps:

[0074] Step (1): Mix a titanium source (specifically metatitanic acid) and a lithium source (specifically lithium carbonate), then add them into a magnetic field sintering furnace. Perform the first magnetic field sintering at a magnetic flux coil current of 5 A and a heating rate of 10 °C / min from room temperature to 200 °C for 1.5 hours, and then cool with the furnace to obtain the first precursor. Among them, the molar ratio of Ti in the titanium source to Li in the lithium source is 1:2.1.

[0075] Step (2): Perform the second magnetic field sintering on the first precursor obtained in step (1) at a magnetic flux coil current of 12 A and a heating rate of 10 °C / min from room temperature to 750 °C for 4 hours, and then cool with the furnace to obtain the second precursor.

[0076] Step (3): Perform the third magnetic field sintering on the second precursor obtained in step (2) at a magnetic flux coil current of 10 A and a heating rate of 10 °C / min from room temperature to 400 °C for 1.5 hours, and then cool with the furnace to obtain the third precursor.

[0077] Step (4): Immerse the third precursor obtained in step (3) in a 0.01 mol / L hydrochloric acid solution for acidification. The acidification temperature is 50 °C and the acidification time is 18 hours. Then, filter and vacuum-dry the obtained solid at 50 °C until constant weight to obtain the lithium extraction from salt lake titanium-based adsorbent material.

[0078] Comparative Example 1

[0079] This example provides a lithium extraction from salt lake titanium-based adsorbent material and its preparation method. The difference from Example 1 is only that: the magnetic flux coil currents of the first magnetic field sintering and the second magnetic field sintering are both 13 A, and the temperatures are both 720 °C; the remaining steps and parameters are the same.

[0080] The preparation method of the above lithium extraction from salt lake titanium-based adsorbent material includes the following steps:

[0081] Step (1): Mix a titanium source (specifically metatitanic acid) and a lithium source (specifically lithium carbonate), then add them into a magnetic field sintering furnace. Conduct the first magnetic field sintering for 1.5 hours at a magnetic flux coil current of 13 A, heating from room temperature to 720 °C at a rate of 10 °C / min, and then cool with the furnace to obtain a first precursor; wherein, the molar ratio of Ti in the titanium source to Li in the lithium source is 1:2.1;

[0082] Step (2): Subject the first precursor obtained in step (1) to a second magnetic field sintering for 5 hours at a magnetic flux coil current of 13 A, heating from room temperature to 720 °C at a rate of 10 °C / min, and then cool with the furnace to obtain a second precursor;

[0083] Step (3): Subject the second precursor obtained in step (2) to a third magnetic field sintering for 1.5 hours at a magnetic flux coil current of 13 A, heating from room temperature to 720 °C at a rate of 10 °C / min, and then cool with the furnace to obtain a third precursor;

[0084] Step (4): Immerse the third precursor obtained in step (3) in a 0.01 mol / L hydrochloric acid solution for acidification. The acidification temperature is 50 °C and the acidification time is 18 hours. Then filter and vacuum dry the obtained solid at 50 °C until constant weight to obtain the lithium extraction from salt lake titanium-based adsorbent material.

[0085] Comparative Example 2

[0086] This example provides a lithium extraction from salt lake titanium-based adsorbent material and its preparation method. The difference from Example 1 is only that: sintering is not carried out in a magnetic field atmosphere; the remaining steps and parameters are the same.

[0087] The preparation method of the above-mentioned lithium extraction from salt lake titanium-based adsorbent material includes the following steps:

[0088] Step (1): Mix a titanium source (specifically metatitanic acid) and a lithium source (specifically lithium carbonate), then add them into a sintering furnace. Conduct the first sintering for 1.5 hours at a rate of 10 °C / min, heating from room temperature to 260 °C, and then cool with the furnace to obtain a first precursor; wherein, the molar ratio of Ti in the titanium source to Li in the lithium source is 1:2.1;

[0089] Step (2): Subject the first precursor obtained in step (1) to a second sintering for 5 hours at a rate of 10 °C / min, heating from room temperature to 720 °C, and then cool with the furnace to obtain a second precursor;

[0090] Step (3): Subject the second precursor obtained in step (2) to a third sintering for 1.5 hours at a rate of 10 °C / min, heating from room temperature to 380 °C, and then cool with the furnace to obtain a third precursor;

[0091] Step (4): Immerse the third precursor obtained in step (3) in a 0.01 mol / L hydrochloric acid solution for acidification. The acidification temperature is 50 °C and the acidification time is 18 hours. Then, filter and vacuum dry the obtained solid at 50 °C until constant weight to obtain the lithium extraction from salt lake titanium-based adsorbent material.

[0092] Test Example

[0093] In this example, the lithium extraction from salt lake titanium-based adsorbent materials obtained in Examples 1-3 and Comparative Examples 1-2 above were tested for performance according to the existing test methods.

[0094] Test method: 1) Prepare a high-concentration brine to simulate the salt lake water environment, and its composition mainly includes: Na with a concentration of 16,870 ppm + , Li with a concentration of 320 ppm + , K with a concentration of 2,450 ppm + , Mg with a concentration of 940 ppm 2+ ; 2) Weigh 1 g of the lithium extraction from salt lake titanium-based adsorbent materials obtained in Examples 1-3 and Comparative Examples 1-2 above and put them into 200 mL of brine for stirring for 3 hours. Then, filter to obtain the adsorption filtrate respectively, measure the ion content using an inductively coupled plasma spectrometer, and calculate the adsorption capacity of the Li salt lake lithium extraction titanium-based adsorbent materials provided in each example and comparative example according to Formula 1; 3) Wash each filtered solid phase (i.e., adsorbent) with 1 L of pure water and dry it at 60 °C. Weigh 0.5 g of the solid phase and put it into 100 mL of hydrochloric acid solution with pH = 1, and desorb it at 40 °C for 1 h. After the reaction, filter to obtain the desorption filtrate, measure the ion content using an inductively coupled plasma spectrometer, and calculate the desorption capacity of the Li salt lake lithium extraction titanium-based adsorbent materials provided in each example and comparative example according to Formula 2, and calculate the Li desorption rate of the Li salt lake lithium extraction titanium-based adsorbent materials provided in each example and comparative example according to Formula 3; Among them, Formula 1: Li adsorption capacity (mg / g) = (Li concentration before adsorption test - Li concentration after adsorption test) × 0.2 ÷ 1; Formula 2: Li desorption capacity (mg / g) = (Li concentration in the desorption solution × 0.1) ÷ 0.5; Formula 3: Li desorption rate (%) = (Li desorption capacity ÷ Li adsorption capacity) × 100%.

[0095] The test results are shown in Table 1.

[0096] Table 1

[0097] Test sample Li adsorption capacity (mg / g) Li desorption capacity (mg / g) Li desorption rate (%) Example 1 32.1 31.7 98.8 Example 2 24.9 22.5 90.4 Example 3 25.2 23.2 92.1 Comparative example 1 19.5 11.4 58.5 Comparative example 2 17.8 7.7 43.3

[0098] As can be seen from Table 1, compared with Comparative Examples 1-2, the lithium extraction from salt lake titanium-based adsorbent materials provided in the examples of the present invention have higher Li adsorption capacity and Li desorption rate, which can meet the requirements of industrial production of lithium extraction from salt lake, and the effect of Example 1 is the best. In addition, the electron microscope characterizations of the lithium extraction from salt lake titanium-based adsorbent materials obtained in Example 1, Comparative Example 1 and Comparative Example 2 of the present invention are respectively as Figure 2 , Figure 3 and Figure 4 shown. By comparison, it can be seen that the lithium extraction from salt lake titanium-based adsorbent materials obtained in the examples of the present invention not only have smaller particle sizes, with particle sizes in the range of 30-50 nm, but also have an ordered structure and better morphology.

[0099] In summary, the examples of the present invention provide a lithium extraction from salt lake titanium-based adsorbent material and a preparation method thereof. The present invention adopts a three-stage magnetic field sintering method, and by controlling the condition parameters of each stage, the lithium element adsorption capacity and desorption rate of the obtained titanium-based adsorbent material are significantly improved, providing an efficient and stable titanium-based adsorbent material for the field of lithium extraction from salt lake, and making up for the deficiencies of the prior art.

[0100] The various embodiments of the present invention may exist 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 construed as a rigid limitation on the scope of the present invention; therefore, it should be considered that the described range description has specifically disclosed all possible sub-ranges and single values within that range. For example, it should be considered that the range description from 1 to 6 has 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., and single numbers within that range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. In addition, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.

[0101] The above are only specific embodiments of the present invention, enabling those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for preparing a lithium-titanium adsorption material from a salt lake, characterized in that: The method for preparing the titanium-based adsorption material for lithium extraction from salt lakes comprises the following steps: A titanium source and a lithium source are mixed, and then subjected to a first magnetic field sintering to obtain a first precursor; Sintering the first precursor in a second magnetic field to obtain a second precursor; sintering the second precursor in a third magnetic field to obtain a third precursor; Adding the third precursor into an acidic solution for acidification, filtering and drying, and obtaining the salt lake lithium-extracting titanium-based adsorption material; The working condition parameters of the first magnetic field sintering include: the flux coil current is 2.5-5A, the temperature is 200-280°C, and the time is 1-2 hours; The working condition parameters of the second magnetic field sintering include: the flux coil current is 12-15A, the temperature is 670-750°C, and the time is 4-6 hours; The working condition parameters of the third magnetic field sintering include: the flux coil current is 6-10A, the temperature is 300-400°C, and the time is 1-2 hours.

2. The method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes according to claim 1, characterized in that: The working condition parameters of the first magnetic field sintering include: the flux coil current is 4A, the temperature is 260°C, and the time is 1 to 2 hours.

3. The method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes according to claim 1, characterized in that: The working condition parameters of the second magnetic field sintering include: the flux coil current is 13A, the temperature is 720°C, and the time is 4 to 6 hours.

4. The method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes according to claim 1, characterized in that: The working condition parameters of the third magnetic field sintering include: the flux coil current is 8A, the temperature is 380°C, and the time is 1 to 2 hours.

5. The method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes according to claim 1, characterized in that: The molar ratio of Ti in the titanium source to Li in the lithium source is 1:(2-2.2).

6. The method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes according to claim 1, characterized in that: The titanium source includes at least one of titanium dioxide, metatitanic acid, titanium chloride, titanium sulfate and tetrabutyl titanate.

7. The method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes according to claim 1, characterized in that: The lithium source includes at least one of lithium carbonate, lithium hydroxide, lithium chloride, lithium acetate and lithium nitrate.

8. The method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes according to claim 1, characterized in that: The working condition parameters of the acidification include: the acidification temperature is 45 to 55° C., and the acidification time is 10 to 20 hours.

9. The method for preparing a titanium-based adsorbent material for lithium extraction from salt lakes according to claim 1, characterized in that: The acidic solution is a hydrochloric acid solution with a molar concentration of 0.01-0.1 mol / L.

10. A titanium-based adsorption material for lithium extraction from salt lakes, characterized in that: The titanium-based adsorption material for lithium extraction from salt lakes is prepared by the preparation method described in any one of claims 1 to 9.

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