Preparation method of durable high-adsorption-capacity titanium lithium ion sieve

Abstract

The application discloses a preparation method of titanium lithium ion sieve, which comprises the following steps: mixing lithium salt, titanium salt and a dispersing agent to perform a hydrothermal synthesis reaction, drying and calcining a powder obtained after the hydrothermal synthesis to obtain a titanium lithium ion sieve precursor, adding EVOH (ethylene-vinyl alcohol copolymer) composite glue into the precursor, and performing extrusion molding and granulation and then performing acidification treatment to obtain the titanium lithium ion sieve with high adsorption capacity and high durability. The method has the advantages of simple process and low cost, the service life of the adsorbent can be prolonged by using the EVOH composite glue as a binder, and the method has a good industrial application prospect.

Description

Technical Field

[0001] This article relates to the field of lithium-ion sieve technology, specifically to a method for preparing a titanium-based lithium-ion sieve with high durability and high adsorption capacity. Background Technology

[0002] Lithium resources in nature are mainly distributed in ores and salt lake brines. The lithium resources in salt lake brines are much higher than those in ores, and the cost of lithium extraction from salt lakes is only half that of lithium extraction from ores. Therefore, in terms of both resource quantity and cost, lithium extraction from salt lakes is the main direction for future lithium resource acquisition.

[0003] my country's salt lakes generally suffer from a high magnesium-to-lithium ratio, making them unsuitable for traditional evaporation methods. Currently, the main methods for lithium extraction from Chinese salt lakes include calcination leaching, membrane separation, salting out, solvent extraction, and ion exchange and adsorption. Among these, calcination leaching is limited by high water evaporation, high energy consumption, and equipment corrosion. Membrane separation, while simple, is limited by high cost and the risk of membrane poisoning. Salting out has stringent environmental requirements and low lithium yield, hindering industrial application. Extraction methods currently commonly use tributyl phosphate as the extractant, but the back-extraction process requires hydrochloric acid, which corrodes equipment and limits its development and application.

[0004] The currently proven global lithium reserves, calculated in terms of metallic lithium, are approximately 48.46 million tons. Of these, Chile, Bolivia, and Argentina account for 33.02%, 18.57%, and 13.41% of the total reserves, respectively, totaling two-thirds of the world's reserves, and are recognized globally as the "Lithium Triangle."

[0005] my country's lithium reserves account for approximately 22.12% of the global total, with preliminary estimates suggesting potential lithium salt reserves of tens of millions of tons. These reserves are mainly distributed in Qinghai and Tibet. Qinghai's lithium resources are primarily sulfate-type, concentrated in the Qaidam Basin and the northern part of the carbonate-type lithium resource belt in northern Tibet. Tibet's lithium resources are mainly carbonate-type, concentrated in the Zabuye Salt Lake in western northern Tibet and the Bangordujiali Lake in eastern northern Tibet. Among these, the Qaidam Basin in Qinghai and the Zabuye Salt Lake in Tibet possess large and high-grade lithium reserves, making them important resource bases for China's future development of the lithium salt industry.

[0006] Lithium extraction via adsorption technology originates from the aluminum salt precipitation process. The basic principle is to select an adsorbent with selective lithium adsorption capacity to adsorb lithium ions, followed by desorption to separate them. This method is suitable for lithium extraction from salt lakes with high magnesium-to-lithium ratios. The key to adsorption is finding an adsorbent with high adsorption capacity and strong lithium selectivity to eliminate interference from other metal ions in the salt lake, while also being cost-effective and pollution-free. Currently, manganese-based, titanium-based, and aluminum-based adsorbents are widely studied. Aluminum-based adsorbents have low adsorption capacity, and manganese-based adsorbents have high solubility; therefore, titanium-based adsorbents are currently a research hotspot and have broad application prospects.

[0007] Patent CN113041988A discloses a method for hydrothermal synthesis using LiOH, Al2O3, and anatase TiO2. The resulting powder is then calcined to obtain a titanium-based lithium-ion sieve precursor. However, experiments have shown that the hydrothermal synthesis temperature mentioned in this patent is relatively low, and no dispersant is added. After drying and calcination, agglomeration easily occurs, affecting the adsorbent performance. Patent CN116196882A discloses a method using potassium acetate as a potassium source, which is slurried with metatitanic acid, dried, and calcined at high temperature to prepare a potassium metatitanic acid precursor. This patent uses a slurry mixing method to mix the raw materials, resulting in problems such as low product purity, poor dispersibility, and difficulty in controlling particle size. Summary of the Invention

[0008] The purpose of this invention is to provide a method for preparing titanium-based lithium ion sieves with high adsorption capacity, low cost, and high selectivity.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A method for preparing a titanium-based lithium-ion sieve: a lithium-containing compound, a titanium-containing compound, polyethylene glycol PEG400, and water are mixed and subjected to a hydrothermal reaction. The product is dried and calcined to obtain a precursor. The precursor is mixed with EVOH composite adhesive, extruded and granulated, dried, and acidified to obtain the titanium-based lithium-ion sieve.

[0011] The mass ratio of polyethylene glycol (PEG400), total lithium-containing compounds and titanium-containing compounds to water is 0.02–0.03:1:2.8–4:

[0012] The molar ratio of lithium to titanium in lithium-containing and titanium-containing compounds is 1.9–2.2:1;

[0013] The mass ratio of the EVOH composite adhesive to the precursor is 1:9 to 11;

[0014] The EVOH composite adhesive contains EVOH, γ-butyrolactone, and water, with a mass ratio of EVOH, γ-butyrolactone, and water of 0.1–0.33:0.055–0.067:1.

[0015] Some specific preparation methods involve lithium compounds being one or more of lithium hydroxide, lithium carbonate, and lithium chloride, and titanium compounds being one or more of metatitanic acid, titanium dioxide, and titanic acid.

[0016] Some specific preparation methods involve a hydrothermal reaction temperature of 160℃~200℃, a hydrothermal reaction time of 6~18h, and a stirring speed of 200~250r / min.

[0017] Some specific preparation methods involve drying at 100℃~120℃, calcining at 600℃~700℃, calcining for 4~8h, and heating at a rate of 3~5℃ / min during calcination.

[0018] In some specific preparation methods, when acidification is performed using hydrochloric acid or sulfuric acid with a concentration of 0.1–0.2 mol / L, the temperature is controlled at 40–50℃.

[0019] Some specific preparation methods involve drying at a temperature of 90℃~100℃.

[0020] Some specific preparation methods involve extruding and granulating the material, followed by drying at 90℃~100℃ to remove the pore-forming agent.

[0021] Some specific preparation methods involve acidification treatment where the solution is kept at pH between 1.5 and 2.5, and the acidification process ends when the pH does not change within 1 hour.

[0022] A titanium-based lithium-ion sieve prepared using the aforementioned preparation method.

[0023] Application of the titanium-based lithium-ion sieve in lithium extraction from salt lakes

[0024] The beneficial effects of this invention are as follows:

[0025] 1) This invention uses EVOH as the main component of the composite adhesive for molding. Compared with other polymers, EVOH exhibits better strength, elastic modulus, and flexural properties after molding. Furthermore, EVOH possesses excellent anti-aging and weather resistance, with minimal changes in gloss and mechanical properties over extended use. When used as an adhesive for ion sieve molding, it allows the molded adsorbent to have a longer service life.

[0026] 2) Titanium-based lithium-ion sieve precursors are prepared by hydrothermal synthesis, which has the advantages of high product purity, good dispersibility and easy particle size control.

[0027] 3) PEG400 was added as a dispersant to make the powder dispersed evenly and prevent agglomeration after calcination.

[0028] 4) The preparation method of the present invention is low in cost and simple in process, suitable for large-scale production, and ensures high selectivity for Li element while having high adsorption capacity. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0030] Figure 1 This is a scanning electron microscope image of a titanium-based lithium-ion sieve precursor.

[0031] Figure 2 This is the experimental result diagram for test example 2.

[0032] Figure 3 This is the experimental result diagram for test example 3. Detailed Implementation

[0033] The embodiments and comparative examples further illustrate the implementation methods and effects of the present invention, but the scope of protection of the present invention is not limited to the contents listed in the embodiments.

[0034] Example 1

[0035] Weigh 1.7 kg of lithium hydroxide monohydrate powder, 1.9 kg of metatitanic acid powder, 72 g of polyethylene glycol PEG400, and 12.2 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reactor was subjected to hydrothermal reaction at 200 r / min and 160℃ for 6 h. The hydrothermal reaction material was filtered and dried in an oven at 120℃ for 8 h. The dried powder was then calcined in a muffle furnace to obtain the ion sieve precursor at 600℃ for 4 h with a heating rate of 5℃ / min.

[0036] Dissolve 60g EVOH in 300g deionized water, add 20g porogen γ-butyrolactone to prepare a composite adhesive, mix the ion sieve precursor with the prepared composite adhesive evenly, then extrude and granulate, and dry at 100℃ to remove the porogen to obtain the ion sieve.

[0037] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash with water until neutral, and dry to obtain titanium-based lithium ion sieve.

[0038] Figure 1 This is a scanning electron microscope (SEM) image (Hitachi SU5000) of a titanium-based lithium-ion sieve precursor. The image shows tiny blocky structures, which are formed by a solid-state reaction between metatitanic acid and lithium hydroxide monohydrate under high-temperature calcination, resulting in Li₂TiO₃.

[0039] Example 2

[0040] Weigh 1.7 kg of lithium hydroxide monohydrate powder, 1.9 kg of metatitanic acid powder, 90 g of polyethylene glycol PEG400, and 14.4 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction was carried out at 200 r / min and 180℃ for 6 h. The hydrothermal reaction was then carried out in an oven at 120℃ for 8 h. After drying, the material was calcined in a muffle furnace to obtain the ion sieve precursor at 600℃ for 4 h with a heating rate of 5℃ / min.

[0041] 60g of EVOH was dissolved in 300g of deionized water, and 20g of γ-butyrolactone was added as a porogen to prepare a composite colloid. The prepared composite colloid was added to the ion sieve precursor, mixed evenly, extruded and granulated, and dried at 100℃ to remove the porogen to obtain the ion sieve.

[0042] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash with water until neutral, and dry to obtain titanium-based lithium ion sieve.

[0043] Example 3

[0044] Weigh 1.55 kg of lithium hydroxide monohydrate powder, 1.9 kg of metatitanic acid powder, 86 g of PEG400, and 10.35 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction speed is 200 r / min, the temperature is 200℃, and the hydrothermal reaction time is 6 h. The hydrothermally synthesized material is placed in an oven to dry at 120℃ for 8 h. After drying, it is placed in a muffle furnace for calcination to obtain the ion sieve precursor at 650℃ for 3 h with a heating rate of 5℃ / min.

[0045] 60g of EVOH was dissolved in 270g of deionized water, and 18g of γ-butyrolactone was added as a porogen to prepare a composite colloid. The prepared composite colloid was added to the ion sieve precursor, mixed evenly, extruded and granulated, and dried at 100℃ to remove the porogen to obtain the ion sieve.

[0046] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash with water until neutral, and dry to obtain titanium-based lithium ion sieve.

[0047] Example 4

[0048] Weigh 1.63 kg of lithium hydroxide monohydrate powder, 1.9 kg of metatitanic acid powder, 105 g of PEG400, and 12.2 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction was carried out at 200 r / min and 200℃ for 12 h. The hydrothermal synthesis material was then placed in an oven to dry at 120℃ for 8 h. After drying, the material was placed in a muffle furnace for calcination to obtain the ion sieve precursor at 600℃ for 4 h with a heating rate of 5℃ / min.

[0049] 60g of EVOH was dissolved in 300g of deionized water, and 20g of γ-butyrolactone was added as a porogen to prepare a composite colloid. The prepared composite colloid was added to the ion sieve precursor, mixed evenly, extruded and granulated, and dried at 100℃ to remove the porogen to obtain the ion sieve.

[0050] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash with water until neutral, and dry to obtain titanium-based lithium ion sieve.

[0051] Example 5

[0052] Weigh 1.79 kg of lithium hydroxide monohydrate powder, 1.9 kg of titanium dioxide powder, 82 g of PEG400, and 13.2 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction was carried out at 200 r / min and 200℃ for 20 h. The hydrothermal synthesis material was then placed in an oven to dry at 120℃ for 8 h. After drying, the material was placed in a muffle furnace for calcination to obtain the ion sieve precursor at 650℃ for 3 h with a heating rate of 5℃ / min.

[0053] 75g of EVOH was dissolved in 310g of deionized water, and 18g of γ-butyrolactone was added as a porogen to prepare a composite colloid. The prepared composite colloid was added to the ion sieve precursor, mixed evenly, extruded and granulated, and dried at 100℃ to remove the porogen to obtain the ion sieve.

[0054] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash with water until neutral, and dry to obtain titanium-based lithium ion sieve.

[0055] Example 6

[0056] Weigh 1.74 kg of lithium chloride powder, 1.9 kg of metatitanic acid powder, 73 g of PEG400, and 12.2 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction speed is 200 r / min, the temperature is 160℃, and the hydrothermal reaction time is 6 h. The hydrothermally synthesized material is placed in an oven to dry at 120℃ for 8 h. After drying, it is placed in a muffle furnace for calcination at 600℃ for 4 h to obtain the ion sieve precursor at a heating rate of 5℃ / min.

[0057] 60g of EVOH was dissolved in 300g of deionized water, and 20g of γ-butyrolactone was added as a porogen to prepare a composite colloid. The prepared composite colloid was added to the ion sieve precursor, mixed evenly, extruded and granulated, and dried at 100℃ to remove the porogen to obtain the ion sieve.

[0058] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash with water until neutral, and dry to obtain titanium-based lithium ion sieve.

[0059] Comparative Example 1

[0060] Weigh 1.7 kg of lithium hydroxide powder, 1.9 kg of metatitanic acid powder, and 12.2 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction speed is 200 r / min, the temperature is 200℃, and the hydrothermal reaction time is 20 h. The hydrothermally synthesized material is placed in an oven to dry at 120℃ for 8 h. After drying, it is placed in a muffle furnace for calcination to obtain the ion sieve precursor. The calcination temperature is 600℃ for 4 h and the heating rate is 5℃ / min.

[0061] 60g of EVOH was dissolved in 300g of deionized water, and 20g of γ-butyrolactone was added as a porogen to prepare a composite colloid. The prepared composite colloid was added to the ion sieve precursor, mixed evenly, extruded and granulated, and dried at 100℃ to remove the porogen to obtain the ion sieve.

[0062] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash with water until neutral, and dry to obtain the ion sieve.

[0063] Comparative Example 2

[0064] Weigh 1.7 kg of lithium hydroxide powder, 1.9 kg of metatitanic acid powder, and 12.2 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction speed is 200 r / min, the temperature is 200℃, and the hydrothermal reaction time is 20 h. The hydrothermally synthesized material is placed in an oven to dry at 120℃ for 8 h. After drying, it is placed in a muffle furnace for calcination at 600℃ for 4 h to obtain the ion sieve precursor. The heating rate is 5℃ / min.

[0065] 60g of PVC was dissolved in 300g of deionized water, and 20g of γ-butyrolactone was added as a porogen to prepare a composite adhesive. The prepared composite adhesive was added to the ion sieve precursor, mixed evenly, extruded and granulated, and dried at 100℃ to remove the porogen to obtain the ion sieve.

[0066] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash with water until neutral, and dry to obtain the ion sieve.

[0067] Test Example 1

[0068] Preparation of simulated brine: The raw materials for preparing the brine and the content of various substances and elements in the brine are shown in Table 1.

[0069] Table 1. Brine preparation methods and ion content.

[0070] relative molecular mass raw material Content in brine (g / L) Element types Content in brine (g / L) 42.39 LiCl (anhydrous lithium chloride) 1.30 <![CDATA[Li + ]]> 0.21 58.44 NaCl (anhydrous sodium chloride) 15.00 <![CDATA[Na + ]]> 5.89 74.55 KCl (anhydrous potassium chloride) 8.00 K+ 4.178 111 CaCl2 (anhydrous calcium chloride) 0.60 <![CDATA[Ca 2+ ]]> 0.216 95.21 MgCl2 (anhydrous magnesium chloride) 5.50 <![CDATA[Mg 2+ ]]> 1.34 <![CDATA[Cl - ]]> 18.57

[0071] 1g of the ion sieves prepared in the examples and comparative examples were added to 200ml of simulated brine for adsorption experiments. The adsorption time was 3h. The change in lithium content in the brine was determined by ICP, and the adsorption capacity was calculated using the following formula:

[0072] Q=(p0-ρ1)V / m

[0073] Q represents the adsorption capacity (mg / g), ρ0 represents the initial lithium ion concentration in the solution (mg / L), ρ1 represents the lithium ion concentration after adsorption (mg / L), m represents the mass of the adsorbent (g), and V represents the volume of the adsorption solution (L). After adsorption, the adsorbent was washed and dried for desorption experiments. The desorption temperature was 50℃, the desorption time was 1 h, and the acid used for desorption was 0.1 mol / L hydrochloric acid. After desorption, the concentrations of lithium, sodium, potassium, calcium, and magnesium in the eluent were determined by ICP, and the concentrations of sodium, potassium, calcium, and magnesium were compared with the lithium concentration. The results are shown in Table 2.

[0074] Table 2 Adsorption capacity and selectivity data for the examples and comparative examples.

[0075]

[0076] Test Example 2

[0077] Weigh 1.7 kg of lithium chloride powder, 1.9 kg of metatitanic acid powder, 70 g of PEG400, and 12.2 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction speed is 200 r / min, the temperature is 160℃, and the hydrothermal reaction time is 6 h. The hydrothermally synthesized material is placed in an oven to dry at 120℃ for 8 h. After drying, it is placed in a muffle furnace for calcination at 600℃ for 4 h to obtain the ion sieve precursor at a heating rate of 5℃ / min.

[0078] 60g of EVOH was dissolved in 300g of deionized water, and 20g of γ-butyrolactone was added as a porogen to prepare a composite colloid. The prepared composite colloid was added to the ion sieve precursor, mixed evenly, extruded and granulated, and dried at 100℃ to remove the porogen.

[0079] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash until neutral, and then dry.

[0080] The adsorption-desorption steps were repeated 140 times using the method described in Test 1. Adsorption capacity and adsorbent mass were recorded every 10 cycles. The initial adsorption capacity was 14.2 mg / g, and after 140 cycles, it decreased to 14.0 mg / g. The initial adsorbent mass was 10 g, which decreased to 9.9 g after 140 cycles. Specific data are as follows: Figure 2 As shown.

[0081] Test Example 3

[0082] Weigh out 1.7 kg of lithium hydroxide powder, 1.9 kg of metatitanic acid powder, and 12.2 kg of deionized water, mix them evenly, and put them into a high-pressure reactor. The reaction speed is 200 r / min, the temperature is 200℃, and the hydrothermal reaction time is 20 h. The hydrothermally synthesized material is placed in an oven to dry at 120℃ for 8 h. After drying, it is placed in a muffle furnace for calcination at 600℃ for 4 h with a heating rate of 5℃ / min.

[0083] Dissolve 60g of PVC in 300g of deionized water, add 20g of γ-butyrolactone as a porogen to prepare a composite adhesive, add the prepared composite adhesive to the ion sieve precursor, mix evenly, extrude and granulate, and dry at 100℃ to remove the porogen.

[0084] Acidification treatment: Add 10g of the prepared ion sieve to 200ml of deionized water, water bath temperature 50℃, add 0.15mol / L hydrochloric acid dropwise, and stop the acidification treatment when the pH value of the solution remains unchanged at 1.8 for one hour. Filter, wash until neutral, and then dry.

[0085] The adsorption-desorption steps were repeated 140 times using the method described in Test 1. Adsorption capacity and adsorbent mass were recorded every 10 cycles. The initial adsorption capacity was 12.3 mg / g, and after 140 cycles, it decreased to 11.2 mg / g. The initial adsorbent mass was 10 g, which decreased to 9.1 g after 140 cycles. Specific data are as follows: Figure 3 As shown.

Claims

1. A method of preparing a titanium-based lithium ion sieve, characterized by: The lithium-containing compound, the titanium-containing compound, polyethylene glycol PEG400 and water are mixed to perform a hydrothermal reaction, the product is dried and calcined to obtain a precursor, the precursor is mixed with EVOH compound adhesive to be extruded and granulated, and the granules are dried and treated by acidification to obtain the titanium-based lithium ion sieve; The mass ratio of the total amount of polyethylene glycol PEG400, the lithium-containing compound and the titanium-containing compound to water is 0.02-0.03:1:2.8-4; The molar ratio of lithium to titanium in the lithium-containing compound and the titanium-containing compound is 1.9-2.2:1; The mass ratio of the EVOH compound adhesive to the precursor is 1:9-11; The EVOH compound adhesive comprises EVOH, γ-butyrolactone and water, and the mass ratio of EVOH, γ-butyrolactone and water is 0.1-0.33:0.055-0.067:1; The temperature of the hydrothermal reaction is 160-200°C, and the time of the hydrothermal reaction is 6-18h.

2. The method for preparing a titanium-based lithium-ion sieve according to claim 1, characterized in that: The lithium-containing compound is one or more of lithium hydroxide, lithium carbonate and lithium chloride, and the titanium-containing compound is one or more of metatitanic acid, titanium dioxide and titanic acid.

3. The method for preparing a titanium-based lithium-ion sieve according to claim 1, characterized in that: The stirring speed of the hydrothermal reaction is 200-250r / min.

4. The method for preparing a titanium-based lithium-ion sieve according to claim 1, characterized in that: The drying temperature is 100-120°C, the calcination temperature is 600-700°C, the calcination time is 4-8h, and the heating rate during calcination is 3-5°C / min.

5. The method for preparing a titanium-based lithium-ion sieve according to claim 1, characterized in that: When the acidification treatment is performed by using hydrochloric acid or sulfuric acid with a concentration of 0.1-0.2mol / L, the temperature is controlled at 40-50°C.

6. The method for preparing a titanium-based lithium-ion sieve according to claim 1, characterized in that: The drying temperature is 90-100°C.

7. The titanium-based lithium ion sieve prepared by the preparation method according to any one of claims 1-6.

8. The titanium-based lithium ion sieve according to claim 7 in the application of salt lake lithium extraction.

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