Preparation method of lithium extraction aluminum adsorbent

Abstract

The invention discloses a preparation method of a lithium extraction aluminum adsorbent, which comprises the following steps of: mixing and calcining aluminum oxide, aluminum silicate, lithium oxide or lithium hydroxide, lanthanum oxide, cerium oxide, magnesium oxide, zinc oxide and zirconium oxide serving as raw materials to obtain a precursor, washing and activating by acid and alkali, and replacing lithium ions in the material to form a space vacancy, thereby obtaining the lithium extraction aluminum adsorbent. The adsorbent performance is improved. According to the invention, the adsorption capacity, selectivity and stability of the adsorbent are improved, the production cost is reduced, and a more efficient and economical method is provided for extraction of lithium resources.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium resource extraction, and in particular to a method for preparing an aluminum-based adsorbent for lithium extraction, aiming to improve the extraction efficiency of lithium resources and the stability of the adsorbent. Background Art

[0002] As global demand for clean energy increases, lithium, a key raw material, is increasingly used in batteries, energy storage, and other fields. Traditional lithium extraction methods suffer from high energy consumption and low efficiency. Aluminum-based adsorbents are widely used in lithium extraction due to their low cost and excellent adsorption properties. However, existing aluminum-based adsorbents are prone to problems such as low adsorption capacity and insufficient stability during long-term use. Summary of the Invention

[0003] The present invention addresses the shortcomings of the prior art by providing a method for preparing an aluminum-based adsorbent for lithium extraction. By optimizing the adsorbent's composition and preparation process, the present invention aims to improve the adsorption capacity, selectivity, and stability of the adsorbent, reduce production costs, and enhance the efficiency of lithium resource extraction.

[0004] To solve the above problems, the present invention adopts the following solution: A method for preparing a lithium-extracting aluminum-based adsorbent, characterized in that it comprises the following steps: A: Evenly mix the main material, active ingredient, modifier and additives, wherein the main material accounts for 40%-80% of the total mass, the active ingredient accounts for 10%-30% of the total mass, the modifier accounts for 10%-40% of the total mass, and the additives account for 0%-10% of the total mass; B: Grind the mixed materials to increase the reaction rate between the materials, increase the embedding amount of active ingredients, and improve the adsorption capacity; C: Mix the ground mixture with water to form a slurry, ensuring that all components can be fully mixed and reacted; D: Stir the slurry thoroughly and continuously, and then dehydrate it by spraying; E: The dehydrated particles are sintered at high temperature, and ion migration occurs in the molten state to form an adsorbent precursor; F: The adsorbent precursor is sequentially acid-washed and alkaline-washed to remove impurities, purify components, increase the effective adsorption sites of the precursor, and improve adsorption performance; G: Lithium ions in the structure are released by water washing to form memory vacancies; H: Aluminum-based lithium adsorbent has the structure of Li / Al LDH and the chemical formula is LiCl·2Al(OH)3·nH2O; Among them, the main material is aluminum oxide, the modifier is aluminum silicate, the active ingredient is one or both of lithium oxide and lithium hydroxide, and the auxiliary agent is one or more of lanthanum oxide, cerium oxide, magnesium oxide, zinc oxide, and zirconium oxide.

[0005] Furthermore, the preparation method of the lithium-extracting aluminum-based adsorbent is characterized in that the particle size of the mixed material after grinding is 0.1~1000μm; the solid-liquid ratio of the crushed material to water is 1:10-10:1; the sintering temperature is 500-1500℃, and the calcination time is 1-10h; hydrochloric acid is used for acid washing with an acid concentration of 0.1-10mol / L, and sodium hydroxide is used for alkaline washing with an alkali concentration of 0.1-10mol / L; the drying temperature is 50-100℃, and the drying time is 2-10h.

[0006] The technical effects of the present invention are as follows: the aluminum-based composite adsorbent of the present invention increases the mass ratio of the active component in the unit mass of the adsorbent by introducing aluminum silicate, active components and auxiliary agents, and is activated by acid and alkali washing, and then increases the adsorption active sites through modifiers and auxiliary agents, strengthens the structural strength and stability of the adsorbent, and significantly improves the adsorption capacity, selectivity and regeneration performance of the adsorbent; the preparation method is simple, easy to industrialize, and environmentally friendly; the adsorbent has excellent stability and durability, can be reused many times, and reduces production costs; it realizes efficient and green extraction of lithium resources, which is conducive to promoting the sustainable development of the new energy industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 The present invention is a flow chart of a lithium-aluminum adsorbent and a preparation method thereof.

[0008] Figure 2 Example 1: Line graph of adsorption capacity changes during cyclic testing.

[0009] Figure 3 This is the XRD spectrum of the lithium-aluminum adsorbent before and after adsorption in brine. DETAILED DESCRIPTION

[0010] The present invention will be further described in detail below with reference to the accompanying drawings. Example

[0011] 1) Aluminum oxide accounting for 50%-70% of the total mass, aluminum silicate accounting for 10%-30% of the total mass, aluminum oxide and lithium hydroxide accounting for 5%-20% of the total mass, and additives accounting for 0%-5% of the total mass are mixed uniformly to obtain a mixed material.

[0012] 2) Grinding the mixture in step 1) to obtain a fine powder material with a size of 0.5-500 μm.

[0013] 3) The fine powder material in step 2) is mixed with deionized water at a solid-liquid ratio of 0.5:1 to 5:1 to form a uniform slurry.

[0014] 4) The slurry in step 3) is spray-dried to obtain dry particles.

[0015] 5) The dried particles in step 4) are calcined in a muffle furnace at 800-1200° C. for 2-5 hours to obtain a composite adsorbent precursor.

[0016] 6) The composite adsorbent precursor in step 5) is washed and activated in a 1 mol / L hydrochloric acid solution and a sodium hydroxide solution to remove impurities and improve adsorption performance.

[0017] 7) The adsorbent after impurity removal in step 6) is washed with deionized water and dried at 50-80° C. for 2-4 hours, and then sieved to obtain the product.

[0018] The present invention will be further described below with reference to specific embodiments: Example 1

[0019] 60% aluminum oxide, 10% sodium silicate, 25% lithium oxide and 5% lanthanum oxide were mixed evenly to obtain a mixed powder. The mixed powder was added to an appropriate amount of deionized water, stirred evenly and spray-dried to obtain dry particles. The dry particles were calcined at 800°C for 2 hours to obtain a precursor. The precursor was sequentially treated with 1 mol / L hydrochloric acid pickling and 1 mol / L sodium hydroxide alkaline washing, and finally dried and sieved to obtain the final product. 100mL of adsorbent was filled into the chromatography column, and 10L of salt lake brine (water quality as shown in Table 1) was treated with the adsorbent at a flow rate of 5BV / h, and then eluted with 50°C hot water. The lithium concentration of the eluate was measured, and the results are shown in Table 2. The structural characteristics of the lithium-extracting aluminum adsorbent before and after adsorption in the brine were obtained by X-ray diffraction technology, and the results are shown in Table 2. Figure 3 Repeat the adsorption and elution steps and test the adsorption capacity changes cyclically. The results are shown in Figure 2 shown. Example 2

[0020] Similar to Example 1, the difference lies in the component ratio and calcination conditions. Specifically, 55% of aluminum oxide, 20% of sodium silicate, 20% of lithium hydroxide and 5% of cerium oxide are mixed uniformly to obtain a mixed powder. The subsequent steps are the same as in Example 1. However, the calcination temperature is adjusted to 900°C, and the calcination time is adjusted to 3 hours. Take 100mL of adsorbent and fill it into the chromatography column. 10L of salt lake brine (water quality is shown in Table 1) is treated with the adsorbent at a flow rate of 5BV / h, and then eluted with 50°C hot water. The lithium concentration of the eluate is measured, and the results are shown in Table 2. Example 3

[0021] Similar to Example 1, the difference lies in the component ratio and calcination conditions. Specifically, 60% aluminum oxide, 15% sodium silicate, 20% lithium oxide and 5% cerium oxide were mixed uniformly to obtain a mixed powder. The subsequent steps were the same as in Example 1, but the calcination temperature was adjusted to 800°C and the calcination time was adjusted to 3 hours. 100 mL of adsorbent was filled into the chromatography column, and 10 L of salt lake brine (water quality as shown in Table 1) was treated with the adsorbent at a flow rate of 5 BV / h, and then eluted with 50°C hot water. The lithium concentration of the eluate was measured, and the results are shown in Table 2. Example 4

[0022] Similar to Example 1, the difference lies in the component ratio and calcination conditions. Specifically, 55% of aluminum oxide, 15% of sodium silicate, 25% of lithium hydroxide and 5% of cerium oxide were mixed uniformly to obtain a mixed powder. The subsequent steps were the same as in Example 1, but the calcination temperature was adjusted to 900°C and the calcination time was adjusted to 4 hours. 100 mL of adsorbent was filled into the chromatography column, and 10 L of salt lake brine (water quality as shown in Table 1) was treated with the adsorbent at a flow rate of 5 BV / h, and then eluted with 50°C hot water. The lithium concentration of the eluate was measured, and the results are shown in Table 2.

[0023] Table 1 Salt lake brine water quality Table 2 Adsorption capacity of adsorbent and comparison of water quality before and after adsorption The aluminum-based adsorbent for lithium extraction and its preparation method of the present invention have significant technical benefits and broad application prospects. By optimizing the composition and preparation process, the adsorbent's adsorption capacity, selectivity, and stability are improved, while production costs are reduced, providing a more efficient and economical method for lithium resource extraction.

Claims

1. A method for preparing a lithium-extracting aluminum-based adsorbent, characterized in that: The following steps are involved: A: Evenly mix the main material, active ingredient, modifier and additives, wherein the main material accounts for 40%-80% of the total mass, the active ingredient accounts for 10%-30% of the total mass, the modifier accounts for 10%-40% of the total mass, and the additives account for 0%-10% of the total mass; B: Grind the mixed materials to increase the reaction rate between the materials, increase the embedding amount of active ingredients, and improve the adsorption capacity; C: Mix the ground mixture with water to form a slurry, ensuring that all components can be fully mixed and reacted; D: Stir the slurry thoroughly and continuously, and then dehydrate it by spraying; E: The dehydrated particles are sintered at high temperature, and ion migration occurs in the molten state to form an adsorbent precursor; F: The adsorbent precursor is sequentially acid-washed and alkaline-washed to remove impurities, purify components, increase the effective adsorption sites of the precursor, and improve adsorption performance; G: Lithium ions in the structure are released by water washing to form memory vacancies; H: Obtain aluminum-based lithium extraction adsorbent with the structure of Li / Al-LDH and the chemical formula of LiCl·2Al(OH)3·nH2O; Among them, the main material is aluminum oxide, the modifier is aluminum silicate, the active ingredient is one or both of lithium oxide and lithium hydroxide, and the auxiliary agent is one or more of lanthanum oxide, cerium oxide, magnesium oxide, zinc oxide, and zirconium oxide.

2. The method for preparing the aluminum-based adsorbent for lithium extraction according to claim 1, wherein: The particle size of the mixed material after grinding is 0.1-1000 μm; the solid-liquid ratio of the crushed material to water is 1:10-10:1; the sintering temperature is 500-1500° C., and the calcination time is 1-10 hours; the acid concentration of the pickling is 0.1-10 mol / L, and the alkali concentration of the alkali washing is 0.1-10 mol / L; the drying temperature is 50-100° C., and the drying time is 2-10 hours.

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