Preparation method and application of supported silicon-based manganese lithium ion sieve
The preparation of supported silicon-based manganese lithium-ion sieves by urea co-precipitation solves the problems of high manganese dissolution rate, adsorption capacity decay and poor structural stability of manganese lithium-ion sieves in the process of lithium extraction from salt lakes, and realizes efficient and environmentally friendly development of salt lake lithium resources.
Patent Information
- Application Number
- CN202511064069.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-31
- Publication Date
- 2025-11-07
AI Technical Summary
Existing manganese-based lithium ion sieves suffer from problems such as high manganese dissolution rate, severe adsorption capacity decay, poor structural stability, and easy agglomeration of powdered adsorbents during lithium extraction from salt lakes, which limits their industrial application.
A supported silicon-based manganese lithium ion sieve was prepared by urea co-precipitation. Through hydrothermal reaction and vacuum drying processes, combined with dilute hydrochloric acid leaching treatment, a regular porous structure was formed, which improved the adsorption performance and stability of the manganese lithium ion sieve and prevented powder agglomeration.
It significantly enhances the adsorption capacity and selectivity of manganese-based lithium ion sieves, solves the problem of lithium extraction from salt lake brines with high magnesium-to-lithium ratios, and provides potential for low-cost and high-efficiency industrial applications.
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Figure CN120903515A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of hydrometallurgy, and particularly relates to a preparation method and application of a loaded silicon-based manganese lithium ion sieve. BACKGROUND
[0002] About 72% of global lithium resources exist in salt lake brine, and the lithium reserves in salt lake brine in China account for 79%. However, there are problems such as high magnesium-lithium ratio, high concentration of impurity ions, and high difficulty in separation. Traditional lithium extraction methods such as solvent extraction have problems such as high toxicity of extractant and poor adaptability to high magnesium-lithium ratio. Membrane separation is limited by high membrane cost and easy pollution. Ion exchange resin method has low adsorption capacity. The coprecipitation method consumes a large amount of precipitating agent and has low product purity. The adsorption method has attracted much attention in recent years due to its simple process, low cost, and low environmental hazard. It is crucial to develop an adsorbent material with high adsorption activity, high acid-base tolerance, simple process, and low preparation and use cost for the industrialization of salt lake lithium resources.
[0003] In the current adsorption technology, manganese lithium ion sieve has become a research hotspot for lithium extraction from salt lake due to its high theoretical adsorption capacity and excellent selectivity. However, the existing manganese lithium ion sieve still has the following technical bottlenecks: 1) serious Li capacity attenuation, with more than 20% attenuation after 5 cycles; 2) poor structural stability, with similar radius of Mg 2+ and Li+ ions, leading to pore blockage of the adsorbent; 3) limited industrial application: the powder adsorbent is easy to agglomerate, and the dynamic adsorption column has large pressure drop. The existing improvement technology has not effectively solved the technical bottlenecks of the existing technology, such as the reduction of adsorption capacity caused by Fe / Co doping, and the problem of mass transfer efficiency reduction caused by pore blockage of the silicon-based molecular sieve.
[0004] Therefore, it is urgent to develop a new adsorbent material with high adsorption capacity and low manganese dissolution rate. In view of the present situation, the application aims to provide a preparation method of a loaded silicon-based manganese lithium ion sieve. SUMMARY
[0005] The application proposes a loaded silicon-based manganese lithium ion sieve prepared based on a urea coprecipitation method to optimize the technical bottlenecks of the existing technology such as complex preparation process and low adsorption capacity.
[0006] The technical scheme adopted by the application is as follows:
[0007] A loaded silicon-based manganese lithium ion sieve, and a preparation method thereof, includes the following steps:
[0008] 1) Preparation of precursor: lithium salt, manganese salt and deionized water are mixed and dissolved, excess urea is added to form a metal complex, silicon sol is added dropwise, after reaching the ratio, hydrothermal reaction is carried out, the obtained precipitate is dehydrated by rotary evaporation and then vacuum dried at 60-80℃ for 8 hours, the powder is ground to obtain the precursor, the powder is calcined and cooled to obtain the precursor;
[0009] 2) Preparation of ion sieve: the precursor obtained in step 1) is stirred and acid leached with dilute hydrochloric acid solution, the solid phase is taken by centrifugation, vacuum dried at 60-90℃ for 10 hours to obtain a loaded silicon-based manganese lithium ion sieve (ULMO).
[0010] Further, in the above-mentioned one kind of loaded silicon-based manganese lithium ion sieve, in step 1), the lithium salt is one or a mixture of two or more of lithium nitrate (LiNO3), lithium carbonate (Li2CO3) and lithium acetate (LiCH3COO).
[0011] Further, in the above-mentioned one kind of loaded silicon-based manganese lithium ion sieve, in step 1), the manganese salt is one or a mixture of two or more of manganese nitrate (Mn(NO3)2), manganese sulfate (MnSO4) and manganese acetate (Mn(CH3COO)2).
[0012] Further, in the above-mentioned one kind of loaded silicon-based manganese lithium ion sieve, in step 1), the silicon sol is silica (SiO2) sol with a concentration of 9-31 wt.%; the flow rate of the added silicon sol is 2-3 mL / min.
[0013] Further, in the above-mentioned one kind of loaded silicon-based manganese lithium ion sieve, in step 1), the molar ratio of lithium salt to manganese salt is 3:10-8:10, and the molar ratio of silicon dioxide to manganese salt is 3:2.
[0014] Further, in the above-mentioned one kind of loaded silicon-based manganese lithium ion sieve, in step 1), the hydrothermal reaction temperature is 90-95℃, and the time is 16-18 hours.
[0015] Further, in the above-mentioned one kind of loaded silicon-based manganese lithium ion sieve, in step 1), the calcination is heated to 480-550℃ at a heating rate of 10-20℃ / min, and the calcination is 5-7h.
[0016] Further, in the above-mentioned one kind of loaded silicon-based manganese lithium ion sieve, in step 2), the concentration of the dilute hydrochloric acid solution is 3-4 wt.%; the solid-liquid mass ratio of the precursor to the dilute hydrochloric acid solution is 1:10-1:15.
[0017] Further, in the above-mentioned one kind of loaded silicon-based manganese lithium ion sieve, in step 2), the stirring acid leaching temperature is 20-25℃, and the time is 2-4 hours.
[0018] Application of any of the above-mentioned supported silicon-based manganese lithium-ion sieves in lithium extraction from brine.
[0019] The beneficial effects of this invention are as follows: This invention inhibits the manganese disproportionation reaction through the confinement effect of silicon-based molecular sieves, and improves mass transfer efficiency by combining hierarchical porous structure, significantly enhancing adsorption capacity and selectivity, and effectively solving the problem of lithium extraction from high magnesium-to-lithium ratio salt lake brine; its urea co-precipitation-hydrothermal method preparation process is simple and low-cost, and the resulting supported ion sieve has excellent adsorption performance, the acid leaching delithiation process is mild, and the silicon-based support design avoids the problem of powder agglomeration, providing industrial application potential for the efficient and environmentally friendly development of salt lake lithium resources. Attached Figure Description
[0020] Figure 1 Scanning electron microscope image of the supported silicon-based manganese lithium-ion sieve prepared in Example 1.
[0021] Figure 2 The X-ray diffraction patterns are those of the supported silicon-based manganese lithium-ion sieves prepared in Examples 1, 2, and 3, respectively.
[0022] Figure 3 Fourier transform infrared spectra of the supported silicon-based manganese lithium-ion sieves prepared in Examples 1, 2, and 3, respectively.
[0023] Figure 4 The curves showing the relationship between adsorption capacity and adsorption time for the supported silicon-based manganese lithium-ion sieves prepared in Examples 1, 2, and 3, respectively. Detailed Implementation
[0024] The following specific embodiments further illustrate the content of the present invention, but should not be construed as limiting the present invention. Any modifications or substitutions made to the methods, steps, or conditions of the present invention without departing from the spirit and substance of the present invention should be covered within the scope of the claims of the present invention.
[0025] Example 1
[0026] 1) Preparation of precursors
[0027] Lithium nitrate (LiNO3) and manganese nitrate (Mn(NO3)2) were dissolved in deionized water, and excess urea was added to form a metal complex. Silica sol with a concentration of 9 wt.% was added dropwise at a flow rate of 3 mL / min. The molar ratio of silica, lithium nitrate, and manganese nitrate was 15:5:10. The mixture was subjected to a hydrothermal reaction at 90 °C for 18 hours. The resulting precipitate was dehydrated by rotary evaporation and then vacuum dried at 60 °C for 8 hours. The precipitate was then ground to obtain a precursor powder. The powder was heated to 480 °C at a heating rate of 10 °C / min and calcined for 7 hours. After cooling, the precursor was obtained.
[0028] 2) Preparation of supported silicon-based manganese lithium ion sieve
[0029] The precursor obtained in step 1) was stirred with a dilute hydrochloric acid solution with a concentration of 3 wt.% at 20°C for 2 hours at a solid-liquid mass ratio of 1:10, the solid phase was obtained by centrifugation, and vacuum drying at 60°C for 10 hours to obtain the supported silicon-based manganese lithium ion sieve (ULMO-1).
[0030] The scanning electron microscope results are shown in Figure 1 As can be seen from the figure, the ion sieve prepared has a regular shape and presents a regular hexahedral structure, and the length of the regular hexahedron is about 4 μm. As can be seen from the enlarged view of the manganese lithium ion sieve prepared by the urea coprecipitation method, the surface of the regular hexahedron presents a loose and porous feature, the diameter of the surface particles is about 10 nm, the particle size is uniform, and the micropores are uniformly dispersed.
[0031] Example 2
[0032] 1) Preparation of precursor
[0033] Lithium carbonate (Li2CO3), manganese sulfate (MnSO4) and deionized water were mixed and dissolved, an excess of urea was added to form a metal complex, and a 20 wt.% silica sol was added dropwise at a flow rate of 2.5 mL / min, the molar ratio of silica, lithium carbonate and manganese sulfate was 15:3:10, and the hydrothermal reaction was carried out at a temperature of 95°C for 16 hours. The obtained precipitate was dehydrated by rotary evaporation and vacuum dried at 80°C for 8 hours, and the powder was ground to obtain the precursor powder. The powder was heated to 500°C at a heating rate of 15°C / min, calcined for 6h, and cooled to obtain the precursor.
[0034] 2) Preparation of supported silicon-based manganese lithium ion sieve
[0035] The precursor obtained in step 1) was stirred with a dilute hydrochloric acid solution with a concentration of 3.5 wt.% at 23°C for 3 hours at a solid-liquid mass ratio of 1:13, the solid phase was obtained by centrifugation, and vacuum drying at 80°C for 10 hours to obtain the supported silicon-based manganese lithium ion sieve (ULMO-2).
[0036] Example 3
[0037] 1) Preparation of precursor
[0038] Lithium acetate (LiCH3COO), manganese acetate (Mn(CH3COO)2) and deionized water were mixed and dissolved, excess urea was added to form a metal complex, and a silica sol with a concentration of 31 wt.% was added dropwise at a flow rate of 2 mL / min, the molar ratio of silica, lithium acetate and manganese acetate was 15:8:10, the hydrothermal reaction was carried out at a temperature of 95℃ for 16 hours, the obtained precipitate was dehydrated by rotary evaporation and then vacuum dried at 80℃ for 8 hours, and the powder was obtained by grinding, and the powder was heated to 550℃ at a heating rate of 20℃ / min, and calcined for 5h, and then cooled to obtain the precursor.
[0039] 2) Preparation of supported silicon-based manganese lithium ion sieve
[0040] The precursor obtained in step 1) was stirred with dilute hydrochloric acid with a concentration of 4 wt.% at a solid-liquid mass ratio of 1:15 at 25℃ for 2 hours, the solid phase was obtained by centrifugation, and the supported silicon-based manganese lithium ion sieve (ULMO-3) was obtained by vacuum drying at 80℃ for 10 hours.
[0041] The X-ray diffraction analysis spectrum thereof is shown in Figure 2 From the figure, it can be seen that on the basis of the large peak of silicon dioxide, there are special peaks of ion sieve, and the peak type of the crystal synthesized by this method meets the characteristic peaks of Li4Mn5O 12 (JCPDS 46-0810), and the supported silicon-based manganese lithium ion sieve is successfully synthesized by the urea coprecipitation method. 12 belongs to the Fd-3m space group, and the unit cell parameter a = 8.162, which proves that the supported silicon-based manganese lithium ion sieve is successfully synthesized by the urea coprecipitation method.
[0042] The Fourier transform infrared spectrum thereof is shown in Figure 3 (corresponding to ULMO-2), from the figure, it can be seen that there are symmetric stretching vibration peaks of Si-O-Si at 800cm -1 , bending vibration peaks of Si-O bond at 480cm -1 , special vibration peaks of LiO4 at 526cm -1 , and special vibration peaks of MnO3 -1 and LiO4 at 646cm +6 , and the supported silicon-based manganese lithium ion sieve is successfully synthesized by the urea coprecipitation method.
[0043] Example 4 Application of supported silicon-based manganese lithium ion sieve ULMO in lithium extraction from salt lake brine
[0044] Experimental method:
[0045] 1) Adsorption: Take 1.0 g of ULMO, 100 mL of salt lake brine, adsorb with ULMO at room temperature without adjusting pH, and measure the content of Li in it by atomic absorption spectrometer. +
[0046] 2) Desorption: Transfer ULMO to the elution tank, add 3.5 wt.% dilute hydrochloric acid at a solid-liquid mass ratio of 1:10, and stir for 3 hours at room temperature.
[0047] The adsorption capacity-time relationship curve thereof is shown in Figure 4 From the figure, it can be seen that the adsorption performance curve of the silicon-based molecular sieve prepared by the urea coprecipitation method for lithium shows that the adsorption rate is relatively fast from 0 to 960 min, the adsorption rate gradually decreases from 960 to 3000 min, and gradually tends to adsorption dynamic equilibrium. The three kinds of loaded silicon-based manganese lithium ion sieve take 1440 min to reach the adsorption equilibrium, and the adsorption capacities of ULMO-1, ULMO-2 and ULMO-3 when reaching the equilibrium are respectively 22.20 mg·g -1 , 20.64 mg·g -1 and 20.88 mg·g -1 .
Claims
1. A supported silicon-based manganese lithium ion-sieve, characterized in that, The preparation method comprises the following steps: 1) precursor preparation: lithium salt, manganese salt and deionized water are mixed and dissolved, excess urea is added to form a metal complex, silica sol is added dropwise, after reaching the proportion, hydrothermal reaction is carried out, the obtained precipitate is dehydrated by rotary evaporation and then vacuum dried at 60-80℃ for 8 hours, and the powder is ground to obtain a precursor powder, which is calcined to obtain the precursor after cooling; 2) preparation of ion sieve: the precursor obtained in step 1) is stirred and acid soaked with a dilute hydrochloric acid solution, the solid phase is taken by centrifugation, and a loaded silicon-based manganese lithium ion sieve ULMO is obtained by vacuum drying at 60-90℃ for 10 hours.
2. The supported silicon-based manganese lithium ion-sieve according to claim 1, wherein, In step 1), the lithium salt is one or a mixture of two or more of lithium nitrate, lithium carbonate and lithium acetate. 3.The load-type silicon-based manganese lithium ion sieve according to claim 1, characterized in that, In step 1), the manganese salt is one or a mixture of two or more of manganese nitrate, manganese sulfate and manganese acetate.
4. The supported silicon-based manganese lithium ion-sieve of claim 1, wherein, In step 1), the silica sol is silica sol with a concentration of 9-31wt.%; the flow rate of adding silica sol is 2-3mL / min.
5. The supported silicon-based manganese lithium ion-sieve of claim 4, wherein the silica support is selected from the group consisting of fumed silica, colloidal silica, precipitated silica, and mixtures thereof. In step 1), the molar ratio of lithium salt to manganese salt is 3:10-8:10, and the molar ratio of silica to manganese salt is 3:
2.
6. The supported silicon-based manganese lithium ion-sieve of claim 1, wherein, In step 1), the hydrothermal reaction temperature is 90-95℃, and the time is 16-18 hours.
7. The supported silicon-based manganese lithium ion-sieve of claim 1, wherein the silica support is selected from the group consisting of fumed silica, colloidal silica, precipitated silica, and mixtures thereof. In step 1), the calcination is heated to 480-550℃ at a heating rate of 10-20℃ / min, and calcined for 5-7h. 8.The load-type silicon-based manganese lithium ion sieve according to claim 1, characterized in that, In step 2), the concentration of the dilute hydrochloric acid solution is 3-4wt.%; the solid-liquid mass ratio of the precursor to the dilute hydrochloric acid solution is 1:10-1:
15. 9.The supported silicon-based manganese lithium ion-sieve according to claim 1, wherein, In step 2), the stirring acid soaking temperature is 20-25℃, and the time is 2-4 hours.
10. The use of the loaded silicon-based manganese lithium ion sieve according to any one of claims 1-9 in the lithium extraction from brine.