Porous oriented metatitanic acid adsorbent as well as preparation method and lithium extraction application thereof
Porous oriented metatitanic acid adsorbents were prepared by soft chemical topological synthesis, which solved the problems of small specific surface area and slow mass transfer rate of traditional titanium-based adsorbents, and achieved high-capacity and rapid lithium-ion adsorption, which is suitable for lithium extraction processes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-06
- Publication Date
- 2026-03-13
AI Technical Summary
Existing titanium-based lithium-ion sieve adsorbents have small specific surface areas and slow mass transfer rates, making it difficult to meet the requirements of rapid adsorption-desorption in industrial applications. Furthermore, their cycle stability and selectivity are insufficient.
Porous oriented metatitanic acid adsorbents were prepared by soft chemical topological synthesis. Through the controllable transformation and structural recombination of molecular precursors, a porous structure with significantly increased specific surface area and internal interconnection was formed, achieving high adsorption capacity and fast adsorption rate.
It significantly improves the adsorption capacity and selectivity of lithium ions, shortens the ion diffusion path, and enhances the cycling stability and adsorption rate of the material, making it suitable for efficient and economical lithium extraction processes.
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Figure CN121648868A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of lithium extraction adsorbent materials technology, specifically to a porous oriented metatitanic acid adsorbent, its preparation method, and its lithium extraction application. Background Technology
[0002] With the explosive growth in global demand for lithium resources, the efficient and economical extraction of lithium from liquid lithium deposits such as salt lake brines has become a key technology for the development of the new energy industry. Among the many lithium extraction technologies, adsorption is considered the most promising due to its advantages such as simple operation, good selectivity, and environmental friendliness. Its core lies in the development of high-performance adsorption materials.
[0003] Currently, widely studied inorganic lithium extraction adsorbents mainly include manganese-based, aluminum-based, and titanium-based lithium-ion sieves. Among them, manganese-based lithium-ion sieves (such as λ-MnO2) have a high theoretical adsorption capacity, but they suffer from severe manganese dissolution during acid leaching delithiation, leading to structural collapse and a sharp decline in adsorption performance, resulting in poor cycle stability. Aluminum-based adsorbents (such as aluminum salt complexes) have lower costs, but their adsorption capacity is limited, their adsorption rate is slow, and their selectivity in high magnesium-to-lithium ratio brines is not ideal, restricting their practical application. In contrast, titanium-based lithium-ion sieves (such as H2TiO3) exhibit excellent cycle stability and resistance to dissolution, but their specific surface area is usually small, and the diffusion path of powder materials prepared by traditional high-temperature solid-state methods is long, resulting in an insufficient adsorption rate that cannot meet the requirements of rapid adsorption-desorption processes in industrial applications.
[0004] Therefore, developing a novel titanium-based adsorbent that combines high adsorption capacity, fast adsorption kinetics, and excellent structural stability is currently a research hotspot and challenge in this field. Summary of the Invention
[0005] To address the shortcomings of current lithium extraction adsorbents, this invention innovatively employs a soft chemical topological synthesis method to successfully prepare a porous, oriented titanic acid (H₂TiO₃) adsorbent. This method, under mild conditions, achieves precise control over the material's microstructure through the controllable transformation and structural recombination of molecular precursors. The prepared adsorbent exhibits a significantly increased specific surface area, providing abundant active sites for lithium ion adsorption, thus achieving high adsorption capacity. Simultaneously, its interconnected and oriented porous structure greatly shortens the ion diffusion path, significantly enhancing the adsorption rate. This invention effectively overcomes the drawbacks of traditional titanium-based adsorbents, such as small specific surface area and slow mass transfer rate, developing an adsorbent material with higher capacity, longer lifespan, and excellent selective adsorption, providing an ideal material solution for developing next-generation high-performance lithium extraction technologies.
[0006] To achieve the above objectives, on the one hand, the present invention provides a method for preparing a porous oriented metatitanic acid adsorbent, which includes: taking H... 1.07 Ti1.73 O4, H2Ti2O5, H2Ti4O9, H2Ti5O 11 At least one layered titanate in the mixture is treated with hydrogen peroxide solution (an aqueous solution of hydrogen peroxide), dried, and then mixed and ground evenly with Li2CO3. The ground mixture is then heat-treated at 480~800 ℃ to form Li2TiO3 with a porous structure. Then, it is treated with a low-concentration acid solution to obtain porous H2TiO3, which is a porous oriented metatitanic acid adsorbent.
[0007] As a further preferred technical solution of the present invention, the concentration of hydrogen peroxide solution is 20~40wt%.
[0008] As a further preferred embodiment of the present invention, the Li / Ti molar ratio of the layered titanate to Li2CO3 is 1.5~2.5:1.
[0009] As a further preferred embodiment of the present invention, the heat treatment temperature is 500~700 ℃.
[0010] As a further preferred embodiment of the present invention, the heat treatment time is 1 to 5 hours.
[0011] As a further preferred embodiment of the present invention, the low-concentration acid solution is at least one of acetic acid, hydrochloric acid, and sulfuric acid solution, with a concentration of 0.05~1 mol / L. -1 .
[0012] As a further preferred embodiment of the present invention, the porous H2TiO3 has an orientation in the
[010] crystal axis direction.
[0013] As a further preferred embodiment of the present invention, the layered titanate is selected as H... 1.07 Ti 1.73 O4 or H2Ti2O5 were used to obtain porous H2TiO3 with a porous plate-like structure; the layered titanate was selected as H2Ti4O9 or H2Ti5O. 11 The resulting porous H2TiO3 has a porous rod-like structure.
[0014] According to a second aspect of the present invention, the present invention also provides a porous oriented metatitanic acid adsorbent, which is prepared by the above-described preparation method.
[0015] According to a third aspect of the present invention, the present invention also provides the application of a porous oriented metatitanic acid adsorbent in lithium extraction.
[0016] As a further preferred technical solution of the present invention, porous H₂TiO₃ is placed in a solution containing lithium ions to achieve the adsorption of lithium ions, and then placed in a solution with a concentration of 0.05~1.0 mol / L. -1In a hydrochloric acid solution, lithium ions are desorbed.
[0017] Compared with the prior art, the present invention can achieve the following beneficial effects:
[0018] Traditional methods for preparing lithium extraction adsorbents are complex and have low adsorption capacity and poor selectivity. In contrast, the method for preparing lithium extraction adsorbents of this invention is simple and easy to mass-produce. It achieves efficient, high-capacity and high-selectivity adsorption of lithium ions through ion exchange reaction and pore size coordinated adsorption. Attached Figure Description
[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0020] Figure 1 The image shows the XRD pattern of the porous H2TiO3 obtained in Example 1.
[0021] Figure 2 TEM images of porous H2TiO3 obtained in Examples 1-3.
[0022] Figure 3 The image shown is a SAED diagram of H2TiO3 obtained in Example 1.
[0023] Figure 4 The adsorption capacity curves of porous H2TiO3 for lithium ions obtained in Examples 1-4 are shown.
[0024] Figure 5 A comparison of the adsorption capacity curves of lithium ions for layered titanium peroxide, porous Li2TiO3 and H2TiO3 obtained in Example 1, and H2TiO3 obtained in Comparative Example 1.
[0025] Figure 6 The adsorption selectivity comparison curves of layered titanic acid peroxide and porous H2TiO3 obtained in Example 1 in mixed ionic solutions are shown.
[0026] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0027] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.
[0028] Unless otherwise defined, the technical terms used in the following embodiments have the same meanings as commonly understood by those skilled in the art to which this invention pertains. Unless otherwise specified, the experimental reagents used in the following embodiments are conventional biochemical reagents; and the experimental methods described are conventional methods.
[0029] Example 1
[0030] This embodiment provides a method for preparing porous, oriented plate-like H2TiO3, as detailed below:
[0031] 1) Mix 2g potassium carbonate, 0.36g lithium carbonate, 5g titanium dioxide, and 20g potassium molybdate, then ball-mill until homogeneous. The resulting powder mixture is then calcined at 900℃ for 10 h to obtain layered titanate H. 1.07 Ti 1.73 O4;
[0032] 2) Add 1 g of layered titanate H 1.07 Ti 1.73 O4 was added to 50 mL of 30 wt.% hydrogen peroxide solution to react, and then the mixture was filtered and washed to obtain layered titanic acid peroxide.
[0033] 3) Mix 0.5 g of layered titanic acid peroxide and 0.21 g of lithium carbonate (Li / Ti=2:1) and ball mill them. Then calcine the resulting mixture powder at 500 °C for 3 h to obtain porous plate-like Li2TiO3.
[0034] 4) The porous plate-shaped Li₂TiO₃ was placed in 0.2 mol L⁻¹ -1 After stirring in HCl solution for 8 h, porous plate-like H2TiO3 was obtained.
[0035] The XRD pattern of H2TiO3 obtained in Example 1 is as follows: Figure 1 As shown, it is consistent with the PDF080249 card. Its pore size was measured to be 10 nm, as shown in the figure. Figure 2 As shown in Figure a. Figure 3 The selected area electron diffraction pattern of the porous plate-shaped H2TiO3 obtained in Example 1 shows that H2TiO3 has an orientation along the
[010] crystal axis.
[0036] The lithium extraction adsorbent sample prepared in Example 1 was subjected to the following experimental tests:
[0037] Adsorption experiment: 0.1 g of porous plate-shaped H2TiO3 adsorbent was placed in 100 mL of 1000 mg / L lithium chloride solution and reacted at room temperature for 10 min. After the reaction was completed, layered titanate with intercalated lithium ions was obtained.
[0038] ICP testing was performed on the initial lithium chloride solution and the filtrate collected by vacuum filtration after the reaction to detect the change in lithium ion concentration before and after the reaction, combined with the formula... (Where Q is the adsorption capacity, C0 is the initial lithium ion concentration in the solution, C is the lithium ion concentration in the solution after the reaction, m is the adsorbent mass, and V is the initial solution volume.) Calculate the adsorption capacity. Assuming the adsorbent m is 0.1 g, the initial lithium ion concentration C0 is 1000 mg / L, the lithium ion concentration in the solution after the reaction is 780.26 mg / L, and V is 100 mL, the adsorption capacity is calculated to be 219.74 mg / g according to the formula.
[0039] Desorption experiment: Layered titanate with intercalated lithium ions obtained from the adsorption experiment was placed in 0.1 mol L... -1 After stirring in HCl for 30 min, an ICP test was performed, which showed that lithium ions were completely extracted from the interlayer.
[0040] Selective adsorption experiment; porous H2TiO3 was placed in 100 mg L -1 Contains Li + Na + K + Ca 2+ Mg 2+ The mixture was stirred for 12 hours, the filtrate was collected, and ICP testing was performed. The experimental results are as follows: Figure 6 As shown, the porous H2TiO3 obtained in Example 1 exhibited high selective adsorption of Li+.
[0041] Stability assessment experiment: The above adsorption-desorption experiment was repeated 30 times. The final experimental results showed that after 30 desorption cycles, the layered titanic acid peroxide could still achieve efficient adsorption within 10 min, which was basically the same as the initial effect, proving that it has good cycle stability. The adsorption capacity and adsorption rate remained unchanged after repeated cycles.
[0042] Example 2
[0043] This embodiment provides a method for preparing porous, oriented plate-like H₂TiO₃, which differs from Example 1 only in that the calcination process in step 3) is changed to calcination at 600 °C for 3 h, while the remaining processes are consistent with Example 1. The porous plate-like H₂TiO₃ obtained in Example 2 has a pore size of 12 nm, such as... Figure 2 As shown in b.
[0044] Example 3
[0045] This embodiment provides a method for preparing porous, oriented plate-like H₂TiO₃, which differs from Example 1 only in that the calcination process in step 3) is changed to calcination at 700 °C for 3 h, while the remaining processes are consistent with Example 1. The porous plate-like H₂TiO₃ obtained in Example 2 has a pore size of 15 nm, such as... Figure 2 As shown in c.
[0046] Example 4
[0047] This embodiment provides a method for preparing porous, oriented plate-like H2TiO3, which differs from Example 1 only in that the calcination process in step 3) is changed to calcination at 800 °C for 3 h, while the remaining processes are consistent with Example 1. The porous plate-like H2TiO3 obtained in Example 2 has a pore size of 40 nm. Figure 2 As shown in d.
[0048] Comparative Example 1
[0049] The comparative example provides a method for preparing plate-shaped H2TiO3, which omits the peroxidation treatment step compared to Example 1. The specific preparation method is as follows:
[0050] 1) Mix 2g potassium carbonate, 0.36g lithium carbonate, 5g titanium dioxide, and 20g potassium molybdate, then ball-mill until homogeneous. The resulting powder mixture is then calcined at 900℃ for 10 h to obtain layered titanate H. 1.07 Ti 1.73 O4;
[0051] 3) Mix 0.5 g of layered titanic acid and 0.21 g of lithium carbonate and ball mill them. Then calcine the resulting mixture powder at 600 °C for 2 h to obtain plate-like Li2TiO3.
[0052] 4) Plate-shaped Li₂TiO₃ was placed in 0.5 mol L⁻¹ -1 After stirring in HCl for 24 h, plate-shaped H2TiO3 with plate-like morphology but no pores on the surface was obtained.
[0053] The lithium extraction and adsorption performance of the H2TiO samples prepared above was compared and tested as follows. Specifically, 0.1 g of the sample was placed in 100 mL of 1000 mg / L lithium chloride solution and reacted at room temperature for 10 min. The adsorption capacity of each sample was calculated by ICP test, and the results are shown in Table 1.
[0054] Figure 4 The figure compares the lithium adsorption capacity of the porous plate-shaped H2TiO3 obtained in Examples 1-4. It can be seen from the figure that the porous plate-shaped H2TiO3 obtained in Example 1 has a higher capacity than that in Examples 2-4. Combined with the data in Table 1, this indicates that the smaller pore size of the porous plate-shaped H2TiO3 is beneficial for lithium ion adsorption. Although lowering the calcination temperature can yield metatitanic acid with even smaller pore sizes, after multiple experimental attempts, it was found that porous plate-shaped H2TiO3 products cannot be formed at temperatures below 480 degrees Celsius. Therefore, this invention selects a calcination temperature above 480 degrees Celsius. To consider the molding rate and pore size, the preferred calcination temperature is 500~700 degrees Celsius.
[0055] Table 1 Comparison of pore size and lithium extraction adsorption capacity of H2TiO3 obtained under different conditions
[0056]
[0057] To further demonstrate the beneficial technical effects of the present invention, the peroxide layered titanate H2O2-H involved in Example 1 is used as an example. 1.07 Ti 1.73 O4, porous Li2TiO3, porous H2TiO3 samples, and the plate-shaped H2TiO3 sample of Comparative Example 1 were used as test objects to test their respective lithium extraction adsorption capacities. Specifically, 0.1 g of the sample was placed in 100 mL of 1000 mg / L lithium chloride solution and reacted at room temperature for 10 min. The adsorption capacity of each sample was obtained by ICP test and calculation, and the results are shown in Table 2.
[0058] Table 2 Comparison of adsorption capacity of different samples
[0059]
[0060] Figure 5 A comparison of the lithium-ion adsorption capacity curves of layered titanic acid peroxide, porous Li₂TiO₃ obtained in Example 1, porous H₂TiO₃, and plate-like H₂TiO₃ obtained in Comparative Example 1 is presented. From the figures and the data in Table 2, it can be seen that layered titanic acid peroxide exhibits the lowest adsorption capacity, proving that it is not suitable for lithium extraction. The adsorption capacity of porous Li₂TiO₃ is lower than that of porous H₂TiO₃ because the Li₂TiO₃ before acid exchange... + It is relatively stable in crystals because of the greater amount of Li. + It cannot enter the crystal lattice, but after acid exchange, the resulting H2TiO3 can adsorb more Li through ion exchange. + Furthermore, the adsorption capacity of H2TiO3 obtained in Comparative Example 1 is lower than that of porous H2TiO3, and surface pore formation is beneficial for Li... + Adsorption significantly increases its adsorption capacity.
[0061] Figure 6 The figure shows a comparison curve of the adsorption selectivity of layered titanic acid peroxide and porous H2TiO3 obtained in Example 1 in a mixed ion solution. As can be seen from the figure, in the mixed ion system, layered titanic acid peroxide exhibits selective adsorption of divalent Ca ions, while porous H2TiO3 obtained in Example 1 exhibits high selective adsorption of Li+. Layered titanic acid peroxide is not suitable for lithium extraction adsorption.
[0062] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and various changes or modifications can be made to these embodiments without departing from the principles and essence of the present invention. The scope of protection of the present invention is defined only by the appended claims.
Claims
1. A method for preparing a porous oriented metatitanic acid adsorbent, characterized in that, include: H 1.07 Ti 1.73 O4, H2Ti2O5, H2Ti4O9, H2Ti5O 11 At least one layered titanate in the mixture is treated with hydrogen peroxide solution, dried, and then mixed and ground with Li2CO3 until uniform. The ground mixture is then heat-treated at 480~800 ℃ to form Li2TiO3 with a porous structure. The mixture is then treated with a low-concentration acid solution to obtain porous H2TiO3, which is a porous oriented metatitanic acid adsorbent. The low-concentration acid solution is at least one of acetic acid, hydrochloric acid, and sulfuric acid solution.
2. The method for preparing the porous oriented metatitanic acid adsorbent according to claim 1, characterized in that, The Li / Ti molar ratio of the layered titanate to Li₂CO₃ is 1.5~2.5:
1.
3. The method for preparing the porous oriented metatitanic acid adsorbent according to claim 1, characterized in that, The heat treatment temperature is 500~700 ℃.
4. The method for preparing the porous oriented metatitanic acid adsorbent according to claim 1, characterized in that, The heat treatment time is 1 to 5 hours.
5. The method for preparing the porous oriented metatitanic acid adsorbent according to claim 1, characterized in that, The concentration of the low-concentration acid solution is 0.05~1 mol / L. -1 .
6. The method for preparing the porous oriented metatitanic acid adsorbent according to claim 1, characterized in that, The porous H2TiO3 has an orientation along the [010] crystal axis.
7. The method for preparing the porous oriented metatitanic acid adsorbent according to claim 1, characterized in that, Layered titanate was selected as H 1.07 Ti 1.73 O4 or H2Ti2O5 were used to obtain porous H2TiO3 with a porous plate-like structure; the layered titanate was selected as H2Ti4O9 or H2Ti5O. 11 The resulting porous H2TiO3 has a porous rod-like structure.
8. A porous, oriented metatitanic acid adsorbent, characterized in that, It is prepared by the preparation method according to any one of claims 1-7.
9. Application of a porous oriented metatitanic acid adsorbent in lithium extraction.
10. The application according to claim 9, characterized in that, Lithium ions were adsorbed by placing porous H₂TiO₃ in a solution containing lithium ions, and then placed in a solution with a concentration of 0.05–1.0 mol / L. -1 In a hydrochloric acid solution, lithium ions are desorbed.