Method for preparing silicon-aluminum micro-powder by using triethanolamine mechanically activated lithium slag and product thereof

Abstract

The application discloses a method for preparing silicon-aluminum micro-powder by mechanically activating lithium residue with triethanolamine and a product thereof, and relates to the technical field of recycling of lithium residue; the method mixes lithium residue with a triethanolamine solution and performs ball milling, so that the flowability and dispersibility of the material are improved, the 'buffer layer' effect in the grinding process is reduced, the lithium residue can reach an ideal fineness distribution in a relatively short grinding time, the grinding efficiency is remarkably improved, and the production cycle is shortened; moreover, under the synergistic action of mechanical force, the complexing and dispersing action of triethanolamine on sulfate radicals and iron ions is utilized, the efficiency of dissociation of fine-grained sulfur and iron minerals from the main silicon-aluminum phase is remarkably improved, and the purity of the obtained silicon-aluminum micro-powder product is remarkably improved; the method has the advantages of simple process, good controllability, stable product quality, low energy consumption, short production cycle and the like, and is suitable for large-scale production of high-quality silicon-aluminum micro-powder from lithium residue.

Description

Technical Field

[0001] This invention relates to the field of industrial solid waste treatment technology, mainly to the field of lithium slag recycling technology, and specifically to a method for preparing silicon-aluminum micro powder by mechanically activating lithium slag with triethanolamine and the product thereof. Background Technology

[0002] Lithium slag is a typical industrial waste generated during lithium salt production. Taking the spodumene process for lithium extraction as an example, approximately 8-10 tons of lithium slag are generated for every ton of battery-grade lithium carbonate produced. Based on my country's annual lithium salt production, the annual discharge of lithium slag has reached several million tons and continues to grow. Currently, a large amount of lithium slag is still mainly stored in the open, which not only occupies valuable land resources but also easily causes problems such as dust, heavy metal leakage, and alkali spillage, posing potential pollution risks to the surrounding soil, groundwater, and atmosphere. Therefore, promoting the efficient resource utilization of lithium slag has become a prominent issue that urgently needs to be addressed in the green development and environmental governance of the lithium salt industry.

[0003] From a resource endowment perspective, the total content of SiO2 and Al2O3 in lithium slag can typically reach over 70%, and it possesses potential pozzolanic activity, theoretically making it usable as a cement admixture, concrete additive, or functional filler. However, due to the inherent physical defects of virgin lithium slag, its large-scale and high-value application faces three major technical bottlenecks: First, its coarse particles and dense structure make it difficult to fully dissociate by mechanical force, resulting in the pozzolanic activity not being fully released; second, it contains a certain amount of iron minerals (mainly Fe2O3), leading to a yellowish or grayish base color and low whiteness, and conventional magnetic separation is ineffective in removing iron, severely restricting its application in high-end building materials with high color requirements, such as white silicate cement and decorative concrete; third, the high residual amount of sulfate (calculated as SO3) easily causes sulfate erosion or poor volume stability in concrete, posing a threat to long-term durability.

[0004] To address the aforementioned issues, various modification technologies have been employed for optimization, but each existing technology has its limitations. Traditional physical grinding primarily improves fineness and activity by extending grinding time, but suffers from drawbacks such as high energy consumption, low unit output, and inability to simultaneously reduce sulfur and iron content, resulting in poor economic efficiency. Chemical activation methods (such as adding alkaline activators) can enhance pozzolanic activity to some extent, but often introduce additional sodium and potassium ions, potentially affecting the long-term durability of cement products. A few studies have attempted to remove impurities through acid washing or high-temperature calcination, but these methods are complex, costly, and carry a high risk of secondary pollution, making it difficult to balance efficiency and economy in practical operation.

[0005] Therefore, the current field of lithium slag resource utilization urgently needs a green preparation method that combines efficient grinding, low-energy operation, simultaneous desulfurization and iron removal, and high-purity output. This method should be able to fully dissociate and retain the active silicon and aluminum components under low energy consumption conditions, while efficiently removing harmful impurities such as sulfur and iron, significantly improving the whiteness, purity, and pozzolanic activity of the product, truly realizing the high-value transformation of lithium slag from "low-value disposal" to "high-quality building material functional filler." Summary of the Invention

[0006] The purpose of this invention is to overcome the above-mentioned problems in existing methods for the resource utilization of lithium slag, and to propose a method for preparing silica-alumina micro powder and its product by mechanically activating lithium slag with triethanolamine.

[0007] To achieve the above objectives, the present invention provides a method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag, comprising the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder; (2) The lithium slag powder was mixed with hydrochloric acid and reacted. After the reaction was completed, the mixture was filtered to obtain pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution, mechanical ball milling was performed to obtain a slurry; (4) Place the slurry at 50~70℃ to carry out a complexation reaction to obtain a complexation solution; (5) Add deionized water to the complex solution to precipitate, and obtain the silicon-aluminum micro powder product by solid-liquid separation and drying.

[0008] This invention discloses a method for preparing silica-alumina micropowder using triethanolamine mechanical activation of lithium slag. By mixing and ball-milling lithium slag with a triethanolamine solution, the flowability and dispersibility of the material are improved, reducing the "buffer layer" effect during grinding. This allows the lithium slag to achieve an ideal fineness distribution in a shorter grinding time, significantly improving grinding efficiency and shortening the production cycle. Furthermore, under the synergistic effect of mechanical force, the complexing and dispersing effect of triethanolamine on sulfate and iron ions significantly improves the efficiency of the dissociation of fine-grained sulfur and iron minerals from the main silica-alumina phase, thereby significantly improving the purity of the obtained silica-alumina micropowder product. This invention offers a simple process, good controllability, stable product quality, low energy consumption, and a short production cycle, making it suitable for large-scale production of high-quality silica-alumina micropowder from lithium slag.

[0009] In step (1), preferably, the particle size of the lithium slag powder is no greater than 100 μm; the preferred particle size can better facilitate the reaction and reduce the impurity content in the silicon-aluminum micro powder.

[0010] In step (2), preferably, the concentration of hydrochloric acid is 0.08-0.12 mol / L; the solid-liquid ratio (mass to volume ratio) of the lithium slag powder to hydrochloric acid is 1:8-12 (g / ml); the preferred concentration and amount of hydrochloric acid can better and more thoroughly remove reactive impurities in the lithium slag.

[0011] Preferably, the reaction temperature is 35-45℃ and the time is 20-40 min; the preferred reaction temperature and time result in a more thorough reaction, better removal of reactive impurities, high reaction efficiency, and low energy consumption.

[0012] In step (3), preferably, the concentration of the triethanolamine solution is 1~3 mol / L, and the solid-liquid ratio (mass to volume ratio) of the pretreated lithium slag to the triethanolamine solution is 1:1~3 (g / ml). The preferred triethanolamine can better improve the flowability and dispersibility of the material, thereby more thoroughly dissociating impurities (sulfur and iron minerals) in the silicon-aluminum phase, improving grinding efficiency and product purity.

[0013] Preferably, the ball (mass of grinding balls) to material (mass of pretreated lithium slag) ratio in the mechanical ball mill is 10~20:1; the preferred ball-to-material ratio results in higher ball milling efficiency, which helps to reduce energy consumption and shorten the production cycle.

[0014] Preferably, the speed of the mechanical ball mill is 200-400 r / min, and the time is 4-8 h; the preferred ball milling parameters result in high ball milling efficiency, low energy consumption, and a short ball milling cycle.

[0015] In step (4), preferably, the complexation reaction time is 20-40 min; the preferred complexation time can make the complexation reaction more thorough, which is beneficial to improving product yield and purity.

[0016] In step (5), preferably, the amount of deionized water added is based on the formation of a white flocculent precipitate in the complex solution; that is, when visible, suspended white flocculent matter first appears in the complex solution, and the flocculent matter no longer completely dissolves under stirring, the addition of deionized water should be stopped immediately; the addition of deionized water dilutes and disrupts the complexation-dissolution balance in the original complex solution, and causes the pH value of the system to decrease, resulting in the metal ions (mainly Al) becoming more concentrated. 3+ It settles out.

[0017] Preferably, the precipitate obtained from solid-liquid separation is rinsed at least once with deionized water and anhydrous ethanol alternately.

[0018] To achieve the above objectives, the present invention further provides a silicon-aluminum micro powder product, which is prepared by the above method.

[0019] Preferably, the silica-alumina micro powder product has an SO3 content of less than 0.2 wt%, an Fe2O3 content of less than 0.5 wt%, and a whiteness greater than 78. The preferred silica-alumina micro powder has less impurity content and higher whiteness, making it more suitable for high-performance concrete, white silicate cement, grouting materials and other fields, and thus has a higher market value.

[0020] The beneficial effects of this invention are: 1. This invention utilizes triethanolamine to mechanically activate lithium slag to prepare silicon-aluminum micro powder. By mixing and ball-milling lithium slag with triethanolamine solution, the flowability and dispersibility of the material are improved, and the "buffer layer" effect during the grinding process is reduced. This allows the lithium slag to achieve the ideal fineness distribution in a shorter grinding time, significantly improving grinding efficiency and shortening the production cycle.

[0021] 2. The present invention utilizes triethanolamine to mechanically activate lithium slag to prepare silica-alumina micro powder. Under the synergistic effect of mechanical force, the complexing and dispersing effect of triethanolamine on sulfate and iron ions significantly improves the efficiency of the dissociation of fine-grained sulfur and iron minerals from the main silica-alumina phase, thereby significantly improving the purity of the obtained silica-alumina micro powder product.

[0022] 3. The present invention provides a method for preparing silicon-aluminum micro powder by mechanically activating lithium slag with triethanolamine. The process is simple, controllable, produces stable product quality, consumes little energy, and has a short production cycle. It is suitable for large-scale production of high-quality silicon-aluminum micro powder from lithium slag.

[0023] 4. The silica-alumina micro powder product of this invention has low impurity content and high whiteness, making it suitable for high-performance concrete, white silicate cement, grouting materials and other fields, and thus has higher market value. Attached Figure Description

[0024] Figure 1 This is a process flow diagram of the method for preparing silicon-aluminum micropowder by mechanically activating lithium slag with triethanolamine in Example 1 of the present invention. Detailed Implementation

[0025] The technical solution of the present invention will be further described in detail below with reference to the embodiments.

[0026] The composition and whiteness of the lithium slag raw material used in the specific embodiments of the present invention are shown in Table 1: Table 1. Composition and whiteness of lithium slag raw materials

[0027] Example 1

[0028] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag (process flow as follows) Figure 1 (As shown), including the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0029] Example 2

[0030] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.12 mol / L) at a solid-liquid ratio of 1:8 (g / ml) and stirred (temperature 45℃, time 20 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (1 mol / L) at a solid-liquid ratio of 1:3 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 20:1; speed of 200 r / min; time of 8 h) to obtain slurry; (4) Place the slurry at 50°C and stir for 40 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase twice with deionized water and anhydrous ethanol alternately) and drying treatment (65℃, 2h).

[0031] Example 3

[0032] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.08 mol / L) at a solid-liquid ratio of 1:12 (g / ml) and stirred (at 35℃ for 40 min). After the reaction was completed, the mixture was filtered (vacuum filtered) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (3 mol / L) at a solid-liquid ratio of 1:1 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 10:1; speed of 400 r / min; time of 4 h) to obtain slurry; (4) Place the slurry at 70°C and stir for 20 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (55℃, 4h).

[0033] Example 4

[0034] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:1 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0035] Example 5

[0036] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:3 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0037] Example 6

[0038] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 10:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0039] Example 7

[0040] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 20:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0041] Example 8

[0042] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 4 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0043] Example 9

[0044] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 8 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0045] Example 10

[0046] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 50°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0047] Example 11

[0048] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 70°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0049] Example 12

[0050] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 20 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0051] Example 13

[0052] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 40 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0053] Comparative Example 1

[0054] A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) Mix lithium slag powder with deionized water at a solid-liquid ratio of 1:10 (g / ml) (temperature 40℃, time 30min), filter (vacuum filter) after the mixture is finished to obtain pretreated lithium slag; (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0055] Comparative Example 2

[0056] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with deionized water at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Stir the slurry at 60°C for 30 minutes to obtain a solution; (5) The solution is separated into solid and liquid phases (the solid phase is rinsed three times with deionized water and anhydrous ethanol alternately) and dried (60℃, 3h) to obtain the silicon-aluminum micro powder product.

[0057] Comparative Example 3

[0058] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) The slurry was separated into solid and liquid phases (the solid phase was rinsed three times with deionized water and anhydrous ethanol alternately) and dried (60℃, 3h) to obtain the silicon-aluminum micro powder product.

[0059] Comparative Example 4

[0060] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 80°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0061] Comparative Example 5

[0062] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 40°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0063] Comparative Example 6

[0064] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triisopropanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0065] Comparative Example 7

[0066] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 8:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0067] Comparative Example 8

[0068] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 25:1; speed of 300 r / min; time of 6 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0069] Comparative Example 9

[0070] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical stirring was carried out (speed 300r / min, time 6h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0071] Comparative Example 10

[0072] A method for preparing silica-alumina micro powder using lithium slag includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder (particle size not greater than 100μm). (2) The lithium slag powder was mixed with hydrochloric acid (0.1 mol / L) at a solid-liquid ratio of 1:10 (g / ml) and stirred (at 40℃ for 30 min). After the reaction was completed, the mixture was filtered (vacuum filtration) to obtain the pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution (2 mol / L) at a solid-liquid ratio of 1:2 (g / ml), mechanical ball milling was performed (ball-to-material ratio of 15:1; speed of 300 r / min; time of 10 h) to obtain slurry; (4) Place the slurry at 60°C and stir for 30 min to carry out a complexation reaction to obtain a complex solution; (5) Add deionized water to the complex solution for precipitation (stop when white flocculent precipitate is produced in the complex solution), and obtain the silicon-aluminum micro powder product by solid-liquid separation (washing the solid phase 3 times with deionized water and anhydrous ethanol alternately) and drying treatment (60℃, 3h).

[0073] Experimental example: The silicon-aluminum micro powder products prepared in Examples 1-13 and Comparative Examples 1-10 were subjected to composition and whiteness tests, and the yield of silicon-aluminum micro powder products was statistically analyzed. The results are shown in Table 2.

[0074] Table 2 Test results of silicon-aluminum micro powder products

[0075] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag, characterized in that, Includes the following steps: (1) The lithium slag is crushed and sieved to obtain lithium slag powder; (2) The lithium slag powder was mixed with hydrochloric acid and reacted. After the reaction was completed, the mixture was filtered to obtain pretreated lithium slag. (3) After mixing the pretreated lithium slag with triethanolamine solution, mechanical ball milling was performed to obtain a slurry; (4) Place the slurry at 50~70℃ to carry out a complexation reaction to obtain a complexation solution; (5) Add deionized water to the complex solution to precipitate, and obtain the silicon-aluminum micro powder product by solid-liquid separation and drying.

2. The method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag according to claim 1, characterized in that, In step (1), the particle size of the lithium slag powder is no greater than 100 μm.

3. The method for preparing silica-alumina micropowder using triethanolamine mechanical activation of lithium slag according to claim 1, characterized in that, In step (2), the concentration of hydrochloric acid is 0.08-0.12 mol / L; the solid-liquid ratio of lithium slag powder to hydrochloric acid is 1:8-12.

4. The method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag according to claim 1, characterized in that, In step (2), the reaction temperature is 35-45℃ and the time is 20-40min.

5. The method for preparing silica-alumina micropowder using triethanolamine mechanical activation of lithium slag according to claim 1, characterized in that, In step (3), the concentration of the triethanolamine solution is 1~3 mol / L, and the solid-liquid ratio of the pretreated lithium slag to the triethanolamine solution is 1:1~3.

6. The method for preparing silica-alumina micropowder using triethanolamine mechanically activated lithium slag according to claim 1, characterized in that, In step (3), the ball-to-material ratio of the mechanical ball mill is 10-20:1; the ball milling speed is 200-400 r / min; and the time is 4-8 h.

7. The method for preparing silica-alumina micropowder using triethanolamine mechanical activation of lithium slag according to claim 1, characterized in that, In step (4), the complexation reaction takes 20-40 minutes.

8. The method for preparing silica-alumina micropowder using triethanolamine mechanical activation of lithium slag according to claim 1, characterized in that, In step (5), the amount of deionized water added is based on the formation of a white flocculent precipitate in the complexed solution.

9. A silicon-aluminum micro powder product, characterized in that, The silicon-aluminum micro powder product is prepared by the method described in any one of claims 1-8, which uses triethanolamine to mechanically activate lithium slag to prepare silicon-aluminum micro powder.

10. The silicon-aluminum micro powder product according to claim 9, characterized in that, The silicon-aluminum micro powder product has an SO3 content of less than 0.2 wt%, an Fe2O3 content of less than 0.5 wt%, and a whiteness greater than 78.

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