Preparation Method of a Flotation Capture Agent and Its Application in Flotation of Lepidolite

Abstract

The present invention relates to the technical field of ore dressing, and discloses a preparation method of a flotation capture agent and its application in the flotation of lepidolite. In the present invention, cardanol glycidyl ether and 1,8-diamino-3,6-dioxaoctane are subjected to an epoxy ring-opening reaction, and then a substitution reaction is carried out with sodium chloroacetate to obtain a cardanol-based anionic flotation capture agent. The flotation capture agent is compounded with dodecylamine to form a cationic-anionic composite capture agent, which improves the hydrophobicity and flotability of the mineral surface and facilitates the subsequent froth flotation process. The cardanol-based anionic flotation capture agent has strong surface activity ability. When compounded with dodecylamine to form a cationic-anionic composite capture system, it has stronger foaming performance, a large foam volume, a high foam half-life, and good foam stability. It can promote the contact between the foam and the lepidolite mineral, improve the collecting performance of the foam for lepidolite, and significantly improve the recovery rate of Li 2 O minerals and the grade of lepidolite concentrate.

Description

Technical Field

[0001] The present invention relates to the technical field of ore dressing, and specifically to a preparation method of a flotation collector and its application in the flotation of lepidolite. Background Art

[0002] Lepidolite is a common lithium-containing mineral and one of the important raw materials of lithium resources in China. With the continuous development of medium and high-grade lepidolite, its reserves are gradually decreasing, and the rational development and utilization of lepidolite resources are imminent. Among them, the flotation method is one of the main treatment technologies for lepidolite minerals. Common reagents used in flotation include collectors, frothers, inhibitors, pH adjusters, flocculants, etc. The surfactant with a trapping effect adsorbs on the surface of the target ore powder, and at the same time, the hydrophobic end of the surfactant facing outwards inserts into the bubble, so that the bubble can carry away the specified ore powder to achieve the purpose of ore dressing.

[0003] The collector in the flotation process plays a key role in mineral treatment. Common collectors for lepidolite minerals mainly include hydroxamic acid collectors, cationic collectors, etc. Patent CN114160313B discloses using alkyl sulfonates, sodium oleate, alkyl polyamine ethers, polyoxyethylene sorbitan fatty acid esters, tannins, etc. as flotation collectors for lepidolite, which has the advantages of high flotation efficiency, high adaptability to slime, and large recovery rate of Li 2 O. Compared with a single collector system, the anion-cation composite collector is a new type of flotation system in recent years, which has the advantages of good surface activity ability, strong foaming performance, high adaptability to acidity and alkalinity, and has broad prospects in the field of lepidolite flotation. Summary of the Invention

[0004] (I) Technical Problems to be Solved

[0005] Aiming at the deficiencies of the prior art, the present invention provides a sodium bis-cashew phenol carboxylate flotation collector, which forms an anion-cation collector system with dodecylamine, realizes the efficient flotation of lepidolite, and improves the grade of Li 2 O in the obtained lepidolite concentrate.

[0006] (II) Technical Solutions

[0007] A preparation method of a flotation collector:

[0008] Step (1): Add tetrahydrofuran, cashew phenol glycidyl ether, and 1,8-diamino-3,6-dioxaoctane to a flask, stir and react, then distill under reduced pressure, wash with n-hexane, and recrystallize the product in dichloromethane to obtain intermediate A. The reaction formula is as follows:

[0009]

[0010] Step (2): Add ethanol, intermediate A, sodium chloroacetate, and an aqueous solution of sodium carbonate into the flask. After stirring and reacting, distill off ethanol under reduced pressure. Then extract with dichloromethane. After separation, add anhydrous sodium sulfate to the dichloromethane organic phase to remove water, then filter. The filtrate is recrystallized to obtain the flotation collector. The reaction formula is as follows:

[0011]

[0012] Further, in step (1), the ratio of cardanol glycidyl ether to 1,8-diamino-3,6-dioxaoctane is (2 - 2.2) mol: 1 mol.

[0013] Further, in step (1), the reaction is carried out at 40 - 45 °C for 3 - 5 h.

[0014] Further, in step (2), the ratio of intermediate A, sodium chloroacetate, and sodium carbonate is 1 mol: (2 - 2.4) mol: (4 - 5) mol.

[0015] Further, in step (2), the reaction is carried out at 50 - 60 °C for 4 - 7 h.

[0016] Further, the application of the flotation collector in the flotation of lepidolite. The process of lepidolite flotation is as follows: Crush the original lepidolite ore to a particle size of ≤ 2 mm, then grind it until the particle size of ≤ 74 μm accounts for 70 - 75%; then add it to a flotation cell, add deionized water and stir to make pulp. Control the air flow rate at 0.6 - 0.8 m³ / min, and the stirring speed at 1200 - 1500 rpm; add a pH adjuster to adjust the pH of the pulp to 7 - 8.5; add dodecylamine; after stirring, add the flotation collector; after stirring, add the inhibitor sodium hexametaphosphate, and carry out flotation and foam scraping; after flotation, collect the foam and the pulp in the cell; filter the foam, dehydrate and dry it to obtain the lepidolite concentrate.

[0017] Further, the pH adjuster is sodium carbonate or sodium hydroxide.

[0018] Further, the mass concentration of the flotation collector in the pulp is 20 - 35 mg / L; the mass concentration of dodecylamine is 7 - 13 mg / L.

[0019] Further, the mass concentration of the inhibitor sodium hexametaphosphate in the pulp is 100 - 150 mg / L.

[0020] (III) Technical effects: The present invention uses cardanol glycidyl ether and 1,8-diamino-3,6-dioxaoctane to carry out an epoxy ring-opening reaction, and then a substitution reaction with sodium chloroacetate to obtain a cardanol-based anionic flotation collector.

[0021] The cardanol-based flotation collector of the present invention is compounded with dodecylamine to form a cationic-anionic composite collector. During the flotation process, the dodecylamine cationic collector can interact with the negative charges on the surface of the lepidolite mineral and adsorb on the surface of the lepidolite mineral. Then, the cardanol-based flotation collector contains multiple sodium carboxylate anion groups and undergoes co-adsorption on the lepidolite mineral through a strong electro-neutralization effect. Moreover, the cardanol-based flotation collector contains hydroxyl groups, which have certain hydrogen bond and other interaction forces with the surface of the lepidolite mineral, further improving the adsorption performance of the flotation collector on the surface of the lepidolite mineral; under the synergistic effect of the cardanol-based flotation collector and dodecylamine, the hydrophobicity and flotability of the mineral surface are improved, facilitating the subsequent froth flotation process.

[0022] The cardanol-based anionic flotation collector of the present invention contains a double-cardanol hydrophobic structure, multiple sodium carboxylate and hydroxyl hydrophilic groups, and hydrophilic ether bonds. Therefore, it has strong surface activity, can reduce the surface tension of the solution, improve the foaming ability, and the low surface tension can reduce the internal and external pressure difference of the foam in the solution, thereby improving the stability of the foam. At the same time, it is compounded with dodecylamine to form a cationic-anionic composite capture system, which has stronger foaming performance, a large foam volume, a high foam half-life, and good foam stability, can promote the contact between the foam and the lepidolite mineral, improve the collection performance of the foam for lepidolite, and thus improve the recovery rate of Li 2 O minerals and the grade of lepidolite concentrate. Specific embodiments

[0023] The present invention will be described in detail below by combining specific embodiments, which can more clearly show the content and advantages of the present invention, but do not limit the conditions of the present invention in any way.

[0024] Example 1

[0025] Step (1): Add 250 mL of tetrahydrofuran, 100 mmol of cardanol glycidyl ether, and 50 mmol of 1,8-diamino-3,6-dioxaoctane to a flask, heat to 40 °C, stir and react for 5 h, distill under reduced pressure, wash with n-hexane, and recrystallize the product in dichloromethane to obtain intermediate A.

[0026] Step (2): Add 500 mL of ethanol, 40 mmol of intermediate A, 80 mmol of sodium chloroacetate, and 220 mL of an aqueous solution containing 200 mmol of sodium carbonate to a flask, heat to 60 °C, stir and react for 7 h, then distill off the ethanol under reduced pressure, extract with dichloromethane, add anhydrous sodium sulfate to the dichloromethane organic phase to remove water after separation, then filter, and recrystallize the filtrate to obtain the flotation collector.

[0027] Example 2

[0028] Step (1): Add tetrahydrofuran, 110 mmol of cardanol glycidyl ether, and 50 mmol of 1,8-diamino-3,6-dioxaoctane into a flask, heat to 45 °C, stir and react for 3 h, perform vacuum distillation, wash with n-hexane, and recrystallize the product from dichloromethane to obtain intermediate A.

[0029] Step (2): Add 600 mL of ethanol, 40 mmol of intermediate A, 96 mmol of sodium chloroacetate, and 200 mL of an aqueous solution containing 180 mmol of sodium carbonate into a flask, heat to 55 °C, stir and react for 4 h, then perform vacuum distillation to remove ethanol, then extract with dichloromethane. After separation, add anhydrous sodium sulfate to the dichloromethane organic phase to remove water, then filter, and recrystallize the filtrate to obtain the flotation collector.

[0030] Example 3

[0031] Step (1): Add tetrahydrofuran, 110 mmol of cardanol glycidyl ether, and 50 mmol of 1,8-diamino-3,6-dioxaoctane into a flask, heat to 45 °C, stir and react for 4 h, perform vacuum distillation, wash with n-hexane, and recrystallize the product from dichloromethane to obtain intermediate A.

[0032] Step (2): Add 600 mL of ethanol, 40 mmol of intermediate A, 88 mmol of sodium chloroacetate, and 200 mL of an aqueous solution containing 160 mmol of sodium carbonate into a flask, heat to 50 °C, stir and react for 4 h, then perform vacuum distillation to remove ethanol, then extract with dichloromethane. After separation, add anhydrous sodium sulfate to the dichloromethane organic phase to remove water, then filter, and recrystallize the filtrate to obtain the flotation collector.

[0033] Example 4

[0034] Crush the raw lepidolite ore to a particle size of ≤ 2 mm, then grind it until the particle size of ≤ 74 μm accounts for 70%; then add it to a hanging-cell flotation machine, add deionized water and stir for 3 min to make a pulp with a mass concentration of 55 g / L, control the air flow rate at 0.8 m³ / min, and the stirring speed at 1200 rpm; add the pH regulator sodium carbonate to adjust the pH of the pulp to 7; add dodecylamine, control the mass concentration at 7 mg / L; stir for 2 min, then add the flotation collector (prepared according to the method of Example 1), control the mass concentration at 20 mg / L; stir for 2 min, then add the inhibitor sodium hexametaphosphate, control the mass concentration at 120 mg / L, and perform flotation and foam scraping for 3 min; after flotation, collect the foam and the pulp in the cell; filter the foam and dry it to obtain the lepidolite concentrate.

[0035] Example 5

[0036] The raw lepidolite ore is crushed to a particle size of ≤2 mm, then ground until the particle size of ≤74 μm accounts for 70%; then it is added to a flotation cell, deionized water is added and stirred for 3 min to make a pulp with a mass concentration of 55 g / L, the air flow rate is controlled at 0.6 m³ / min, and the stirring speed is 1200 rpm; the pH adjuster sodium hydroxide is added to adjust the pH of the pulp to 8.5; dodecylamine is added, and the mass concentration is controlled at 8.5 mg / L; after stirring for 2 min, a flotation collector (prepared according to the method of Example 1) is added, and the mass concentration is controlled at 24 mg / L; after stirring for 2 min, the inhibitor sodium hexametaphosphate is added, and the mass concentration is controlled at 150 mg / L, and flotation and foam scraping are carried out for 3 min; after flotation, the foam and the pulp in the cell are collected; the foam is filtered and dried to obtain lepidolite concentrate.

[0037] Example 6

[0038] The raw lepidolite ore is crushed to a particle size of ≤2 mm, then ground until the particle size of ≤74 μm accounts for 70%; then it is added to a flotation cell, deionized water is added and stirred for 3 min to make a pulp with a mass concentration of 55 g / L, the air flow rate is controlled at 0.7 m³ / min, and the stirring speed is 1200 rpm; the pH adjuster sodium carbonate is added to adjust the pH of the pulp to 7.5; dodecylamine is added, and the mass concentration is controlled at 10 mg / L; after stirring for 2 min, a flotation collector (prepared according to the method of Example 1) is added, and the mass concentration is controlled at 28 mg / L; after stirring for 2 min, the inhibitor sodium hexametaphosphate is added, and the mass concentration is controlled at 100 mg / L, and flotation and foam scraping are carried out for 3 min; after flotation, the foam and the pulp in the cell are collected; the foam is filtered and dried to obtain lepidolite concentrate.

[0039] Example 7

[0040] The raw lepidolite ore is crushed to a particle size of ≤2 mm, then ground until the particle size of ≤74 μm accounts for 70%; then it is added to a flotation cell, deionized water is added and stirred for 3 min to make a pulp with a mass concentration of 55 g / L, the air flow rate is controlled at 0.8 m³ / min, and the stirring speed is 1200 rpm; the pH adjuster sodium carbonate is added to adjust the pH of the pulp to 7; dodecylamine is added, and the mass concentration is controlled at 11.5 mg / L; after stirring for 2 min, a flotation collector (prepared according to the method of Example 1) is added, and the mass concentration is controlled at 31 mg / L; after stirring for 2 min, the inhibitor sodium hexametaphosphate is added, and the mass concentration is controlled at 100 mg / L, and flotation and foam scraping are carried out for 3 min; after flotation, the foam and the pulp in the cell are collected; the foam is filtered and dried to obtain lepidolite concentrate.

[0041] Example 8

[0042] Crush the raw lepidolite ore to a particle size of ≤2 mm, then grind it until the particle size of ≤74 μm accounts for 75%; then add it to a flotation cell, add deionized water and stir for 3 min to make a pulp with a mass concentration of 55 g / L, control the air flow rate at 0.8 m³ / min, and the stirring speed at 1500 rpm; add the pH regulator sodium carbonate to adjust the pH of the pulp to 7; add dodecylamine, control the mass concentration at 13 mg / L; after stirring for 2 min, add a flotation collector (prepared according to the method of Example 1), control the mass concentration at 35 mg / L; after stirring for 2 min, add the inhibitor sodium hexametaphosphate, control the mass concentration at 150 mg / L, and carry out flotation and foam scraping for 3 min; after flotation, collect the foam and the pulp in the cell; filter the foam and dry it to obtain lepidolite concentrate.

[0043] Comparative Example 1

[0044] Crush the raw lepidolite ore to a particle size of ≤2 mm, then grind it until the particle size of ≤74 μm accounts for 70%; then add it to a flotation cell, add deionized water and stir for 3 min to make a pulp with a mass concentration of 55 g / L, control the air flow rate at 0.8 m³ / min, and the stirring speed at 1200 rpm; add the pH regulator sodium carbonate to adjust the pH of the pulp to 7; add dodecylamine, control the mass concentration at 7 mg / L; after stirring for 2 min, add the inhibitor sodium hexametaphosphate, control the mass concentration at 120 mg / L, and carry out flotation and foam scraping for 3 min; after flotation, collect the foam and the pulp in the cell; filter the foam and dry it to obtain lepidolite concentrate.

[0045] Comparative Example 2

[0046] Crush the raw lepidolite ore to a particle size of ≤2 mm, then grind it until the particle size of ≤74 μm accounts for 70%; then add it to a flotation cell, add deionized water and stir for 3 min to make a pulp with a mass concentration of 55 g / L, control the air flow rate at 0.8 m³ / min, and the stirring speed at 1200 rpm; add the pH regulator sodium carbonate to adjust the pH of the pulp to 7; add dodecylamine, control the mass concentration at 7 mg / L; after stirring for 2 min, add intermediate A (prepared according to the method of Example 1), control the mass concentration at 20 mg / L; after stirring for 2 min, add the inhibitor sodium hexametaphosphate, control the mass concentration at 120 mg / L, and carry out flotation and foam scraping for 3 min; after flotation, collect the foam and the pulp in the cell; filter the foam and dry it to obtain lepidolite concentrate.

[0047] Comparative Example 3

[0048] The raw lepidolite ore is crushed to a particle size of ≤2 mm, and then ground until the particle size of ≤74 μm accounts for 70%; then it is added to a flotation cell, deionized water is added and stirred for 3 min to prepare a pulp with a mass concentration of 55 g / L, the air flow rate is controlled at 0.8 m³ / min, and the stirring speed is 1200 rpm; the pH regulator sodium carbonate is added to adjust the pH of the pulp to 7; dodecylamine is added, and the mass concentration is controlled at 7 mg / L; after stirring for 2 min, the flotation collector sodium oleate is added, and the mass concentration is controlled at 20 mg / L; after stirring for 2 min, the inhibitor sodium hexametaphosphate is added, and the mass concentration is controlled at 120 mg / L, and flotation and skimming are carried out for 3 min; after flotation, the foam and the pulp in the cell are collected; the foam is filtered and dried to obtain lepidolite concentrate.

[0049] An on-line ore grade detector is used to detect the Li 2 O grade in the lepidolite concentrate. And calculate the Li 2 O recovery rate. The recovery rate = m / m 0 ×100%. m is the mass of Li 2 O in the lepidolite concentrate. m is the mass of Li 2 O in the raw lepidolite ore.

[0050] Foam property test: Taking Example 4 as an example: The raw lepidolite ore is crushed to a particle size of ≤2 mm, and then ground until the particle size of ≤74 μm accounts for 70%; then it is added to a flotation cell, deionized water is added and stirred for 3 min to prepare a pulp with a mass concentration of 55 g / L, the air flow rate is controlled at 0.8 m³ / min, and the stirring speed is 1200 rpm; the pH regulator sodium carbonate is added to adjust the pH of the pulp to 7; the flotation collector (prepared according to the method of Example 1) is added, and the mass concentration is controlled at 20 mg / L; after stirring for 2 min, dodecylamine is added, and the mass concentration is controlled at 7 mg / L; after stirring for 2 min, the inhibitor sodium hexametaphosphate is added, and the mass concentration is controlled at 120 mg / L. The pulp is placed in a sample tube, and a dynamic foam analyzer is used to test the foam properties of the pulp.

[0051] Surface tension test: Taking Example 4 as an example, the flotation collector (prepared according to the method of Example 1) is added to deionized water, and the mass concentration is controlled at 20 mg / L; after stirring for 2 min, dodecylamine is added, and the mass concentration is controlled at 7 mg / L; a surface tension detector is used to test the surface tension of the solution.

[0052] Table 1 Lepidolite concentrate Li 2 O grade test

[0053]

[0054] Table 2 Foam property and surface tension test

[0055]

[0056] As can be seen from Table 1 and Table 2, in Examples 4-8, the cardanol-based flotation collector containing sodium carboxylate was used as an anionic collector, and was compounded with dodecylamine to form an anion-cation composite collector. After flotation, the grade of Li 2 O in the lepidolite concentrate reached 3.17-4.73%, and the recovery rate of Li 2 O reached 80.86-96.01%. The main reason is that during the flotation process, the cardanol-based anionic flotation collector contains a double-cardanol hydrophobic structure, multiple sodium carboxylate and hydroxyl hydrophilic groups, and hydrophilic ether bonds. Therefore, it has strong surface activity, can reduce the surface tension of the solution, improve the foaming ability, and the low surface tension can reduce the internal and external pressure difference of the foam in the solution, thereby improving the foam stability; at the same time, it is compounded with dodecylamine to form an anion-cation composite capture system, which has stronger foaming performance, a large foam volume, and a high foam half-life and good foam stability, which can promote the contact between the foam and the lepidolite mineral, improve the collecting performance of the foam for lepidolite, and thus improve the recovery rate of Li 2 O minerals and the grade of lepidolite concentrate.

[0057] The cardanol-based flotation collector of the present invention is compounded with dodecylamine to form an anion-cation composite collector. During the flotation process, the dodecylamine cationic collector can interact with the negative charges on the surface of the lepidolite mineral and adsorb on the surface of the lepidolite mineral. Then, the cardanol-based flotation collector contains multiple sodium carboxylate anion groups, and through strong electro-neutralization, it co-adsorbs on the lepidolite mineral, and the cardanol-based flotation collector contains hydroxyl groups, which have certain hydrogen bond and other interactions with the surface of the lepidolite mineral; under the synergistic action of the cardanol-based flotation collector and dodecylamine, the hydrophobicity and flotability of the mineral surface are improved, facilitating the subsequent foam flotation process.

[0058] In Comparative Example 1, the cardanol-based flotation collector was not added; the intermediate A in Comparative Example 2 did not contain sodium carboxylate anions, had poor surface activity, and could not be compounded with dodecylamine to form an anion-cation composite capture system. The surface tensions of the collector systems of the two were relatively large, the foaming performance was poor, and the recovery rate of Li 2 O minerals and the grade of lepidolite concentrate were very low.

[0059] Compared with Example 4, in Comparative Example 3, conventional sodium oleate was used as the anionic capturer. As can be seen from Table 2, the surface tension of the sodium oleate and dodecylamine solution is greater than that of Example 4. This is mainly because the cardanol-based flotation capturer contains a bis-cardanol hydrophobic structure and multiple carboxylate and hydroxyl hydrophilic groups, having stronger surface activity ability, which is beneficial to reducing the surface tension of the solution; resulting in the foaming performance of the capturer system in Comparative Example 3 being lower than that of Example 4, and the flotation performance being poor; and compared with sodium oleate, the multiple carboxylate and hydroxyl hydrophilic groups of the cardanol-based flotation capturer have a greater surface interaction force with the lepidolite mineral, and the hydrophobicity and flotability of the mineral surface are higher than those in Comparative Example 3, and the foam flotation performance is better; therefore, the recovery rate of Li 2 O minerals and the grade of the lepidolite concentrate in Comparative Example 3 are lower than those in Example 4.

[0060] This specific embodiment is only an interpretation of the present invention, and it is not a limitation of the present invention. After reading this specification, those skilled in the art can make modifications without creative contributions to this embodiment as needed, but as long as it is within the scope of the claims of the present invention, it is protected by the patent law.

Claims

1. A method for preparing a flotation capture agent, characterized in that: The preparation method of the flotation capture agent is: Step (1), adding tetrahydrofuran, cardanol glycidyl ether, and 1,8-diamino-3,6-dioxaoctane into a flask, stirring for reaction, and then distilling under reduced pressure, washing, and recrystallizing the product in dichloromethane to obtain intermediate A; Step (2), adding ethanol, intermediate A, sodium chloroacetate, and an aqueous solution of sodium carbonate into a flask, stirring the reaction, and then distilling under reduced pressure to remove ethanol, and then extracting with dichloromethane, and after separation, adding anhydrous sodium sulfate to the dichloromethane organic phase to remove water, and then filtering, and recrystallizing the filtrate to obtain a flotation capture agent; In the step (1), the ratio of cardanol glycidyl ether to 1,8-diamino-3,6-dioxaoctane is (2-2.2) mol:1 mol; The structural formula of the cardanol glycidyl ether is , where n is any integer between 0 and 3; The structural formula of the intermediate A is: , where n is any integer between 0 and 3; The structural formula of the flotation capture agent is: , where n is any integer between 0 and 3.

2. The method for preparing a flotation capture agent according to claim 1, characterized in that: In the step (1), the reaction is carried out at 40-45° C. for 3-5 hours.

3. The method for preparing a flotation capture agent according to claim 1, characterized in that: In the step (2), the ratio of intermediate A, sodium chloroacetate and sodium carbonate is 1 mol: (2-2.4) mol: (4-5) mol.

4. The method for preparing a flotation capture agent according to claim 1, characterized in that: In the step (2), the reaction is carried out at 50-60° C. for 4-7 hours.

5. Use of a flotation capture agent obtained by the preparation method according to any one of claims 1 to 4 in the flotation of lepidolite, characterized in that: The lithium mica flotation process is as follows: crushing the lithium mica ore to a particle size of ≤2 mm, then grinding the ore until the particle size of ≤74 μm accounts for 70-75%; then adding the ore to the hanging tank flotation machine, adding deionized water and stirring to form a pulp, and controlling the air flow rate at 0.6-0.8 m 3 / min, stirring speed is 1200-1500rpm; adding pH adjuster; adding dodecylamine; adding flotation capture agent after stirring; adding inhibitor after stirring, flotation scraping foam; collecting foam and ore pulp in the tank after flotation; filtering the foam, dehydrating and drying to obtain lithium mica concentrate.

6. The use of the flotation capture agent according to claim 5 in the flotation of lepidolite, characterized in that: The pH adjusting agent is added to adjust the pH of the slurry to 7-8.5; the pH adjusting agent is sodium carbonate or sodium hydroxide.

7. The use of the flotation capture agent according to claim 5 in the flotation of lepidolite, characterized in that: The mass concentration of the flotation capture agent in the ore pulp is 20-35 mg / L; the mass concentration of dodecylamine is 7-13 mg / L.

8. The use of the flotation capture agent according to claim 5 in the flotation of lepidolite, characterized in that: The mass concentration of the inhibitor in the slurry is 100-150 mg / L, and the inhibitor is sodium hexametaphosphate.

Images