Combined collecting agent for neutral flotation of lepidolite, preparation method and application
By combining amine cations with glycine amphoteric collectors, the problems of equipment corrosion and poor selectivity in lepidolite flotation are solved, achieving efficient lepidolite separation under neutral or weakly alkaline conditions, improving recovery rate and foam flowability, and exhibiting environmentally friendly characteristics.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-21
- Publication Date
- 2026-03-10
AI Technical Summary
Existing lepidolite flotation collectors corrode equipment in strongly acidic media, have poor selectivity, and produce high foam viscosity, making it difficult to efficiently separate fine-particle lepidolite under neutral or weakly alkaline conditions.
A combination of amine cationic collectors and glycine amphoteric collectors is used, with the addition of inhibitors such as water glass or sodium hexametaphosphate, to form synergistic adsorption on the surface of lepidolite, thereby improving selectivity and foam flowability. This method is suitable for neutral to weakly alkaline environments.
It significantly improves the recovery rate of fine-particle lithium mica, has a stable foam layer structure, reduces resource loss, and is environmentally friendly.
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Figure CN121623960A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of mineral flotation, and particularly relates to a combined collector for neutral flotation of lepidolite, a preparation method and application. BACKGROUND
[0002] Lithium is the core raw material of lithium batteries in the fields of new energy vehicles and energy storage devices. With the acceleration of global energy transformation, the demand for lithium resources continues to grow rapidly. As one of the important lithium-containing minerals, lepidolite is particularly rich in granitic pegmatite, and its economic and efficient separation and extraction technology has strategic significance for ensuring stable supply of lithium resources.
[0003] However, lithium mica ore is usually low in grade, and often closely associated with gangue minerals such as feldspar, quartz and mica, with complex mineral composition, which brings great challenges to efficient separation. Flotation is a key method for separating lepidolite, and the core is the selective collecting ability of the collector for lepidolite. Currently, amine cation collectors such as coconut amine and dodecylamine are commonly used in industry to float lepidolite, but such reagents have significant limitations in practical application: first, the best flotation activity usually depends on strong acid medium conditions, which not only aggravates the corrosion of the beneficiation equipment, but also brings environmental and cost pressures; second, when targeting micro-fine particles or severely weathered ores, the selectivity often decreases, and the inhibition effect on gangue minerals is poor, making it difficult to improve the concentrate grade; third, the foam produced by amine collectors is often too viscous and has poor flowability, which is not conducive to the transportation and concentration of the foam, affecting the separation efficiency and operation stability.
[0004] In order to overcome the defects of single collector, combined reagents have become an important direction of flotation reagent research and development. Through the synergistic effect of different reagents, it is expected to achieve efficient and selective collection of target minerals under mild conditions. Therefore, developing a new type of combined collector that can efficiently float in neutral or weak alkaline environment, with good selectivity and foam performance, is of urgent need and important application value for simplifying the lepidolite flotation process, reducing reagent consumption and improving resource utilization. SUMMARY
[0005] In view of the technical defects of the existing lithium mica flotation collector, such as poor selectivity, high foam viscosity, and corrosion of equipment in a strong acid environment, the application provides a combined collector for neutral flotation of lithium mica, a preparation method and application. The combined collector is an amine cationic collector such as dodecylamine, octadecylamine or coconut amine, and a glycine amphoteric collector such as N-lauroylsarcosine sodium, N-cocoylglycine sodium or N-stearoylglycine sodium, which are compounded in a certain amount ratio, and an appropriate amount of water glass, sodium hexametaphosphate and other inhibitors are added. The combined collector significantly enhances the selective collection ability of lithium mica in neutral to weak alkaline slurry through the synergistic adsorption effect on the surface of lithium mica. The problems of traditional amine collectors, such as sticky foam, poor selectivity, and the need for strong acid medium, are solved. The lithium mica is efficiently recovered, and the combined collector has the advantages of good water solubility, low foam viscosity, simple preparation, light equipment corrosion and environmental friendliness, and has great application potential.
[0006] To solve the above technical problems, the basic idea of the technical solution of the application is:
[0007] A combined collector for neutral flotation of lithium mica ore, the combined lithium mica collector includes an amine cationic collector, a glycine amphoteric collector and an inhibitor.
[0008] The combined collector provided by the application utilizes the negative electricity carried by lithium mica under weak alkaline conditions to produce electrostatic adsorption with positively charged amine cation. The glycine amphoteric collector on the surface of lithium mica produces a synergistic effect with the amine cationic collector. The glycine amphoteric collector is inserted into the gaps in the surface of lithium mica that has adsorbed the amine cationic collector. On the one hand, it reduces the mutual repulsion between amine cation molecules on the surface of lithium mica, and on the other hand, it increases the collector density on the surface of lithium mica and increases the hydrophobicity of the surface of lithium mica, thereby improving the selectivity.
[0009] The application uses an amine cationic collector as the main collector and a glycine amphoteric collector as the auxiliary collector, which are compounded in a certain mass ratio to form a combined collector. The combined collector strengthens the flotation separation of low-grade lithium mica and gangue minerals under near-neutral conditions, improves the viscosity and fluidity of the flotation foam, and realizes the recycling of low-grade lithium resources.
[0010] In a preferred example, the glycine amphoteric collector has the general formula RCONHCH2COO - M +wherein R is C8-C18 alkyl or alkenyl group, and M is sodium, potassium or ammonium ion. Specifically, the glycine amphoteric collector is selected from at least one of sodium N-lauroyl sarcosinate, sodium N-cocoyl glycinate, sodium N-stearoyl glycinate. The glycine amphoteric collector in the present application can effectively increase the solubility of the multi-component combined collector, so that the combined collector has better foaming capacity and the foam is fine and easy to break, thereby effectively reducing the viscosity of the flotation foam.
[0011] In the preferred examples, the mass ratio of the amine cationic collector to the glycine amphoteric collector is (1.5-3):1, preferably 2:1.
[0012] In the preferred examples, the amine cationic collector is selected from at least one of dodecylamine, octadecylamine, and cocoylamine.
[0013] In the preferred examples, the depressant is selected from at least one of water glass and sodium hexametaphosphate.
[0014] In the preferred examples, the mass ratio of the depressant to the amine cationic collector to the glycine amphoteric collector is (0.2-0.8):(1.5-3):1.
[0015] A preparation method of a combined collector includes the following steps: mixing 1.5-3 parts by mass of an amine cationic collector with 0.2-0.5 parts by mass of hydrochloric acid, adding 150-300 parts by mass of deionized water, and stirring at a speed of 250-350 r / min for 5-10 min; then adding 1 part by mass of a glycine amphoteric collector and (0.2-0.8) parts by mass of a depressant, and 150-300 parts by mass of deionized water, and continuing to stir for 5-10 min to obtain a combined collector solution.
[0016] A combined collector is used for recovering lithium mica minerals under neutral to weak alkaline conditions.
[0017] In the preferred examples, the flotation method includes: crushing and grinding the lithium mica ore to a suitable particle size, adjusting the pulp to be neutral to weak alkaline, adding the combined collector and the depressant, and then performing roughing, cleaning and scavenging after stirring and aeration to obtain a lithium mica concentrate.
[0018] In the preferred examples, the total amount of the combined collector is 300-800 g / t of raw ore.
[0019] Compared with the prior art, the present application has the following beneficial effects.
[0020] (1) Compared with the traditional flotation method, the recovery rate of micro-fine particle lithium mica is significantly improved, and the loss of lithium mica resources in the beneficiation process is effectively reduced.
[0021] (2) has obvious process advantage: the foam layer structure is stable and has no adhesion phenomenon, the flotation condition is mild (natural pH), and has the environment-friendly characteristics.
[0022] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS
[0023] The accompanying drawings, which are part of this application, serve to provide further understanding of the present application, and the illustrative embodiments of the present application and their description serve to explain the present application, but do not constitute improper limitations on the present application. Obviously, the drawings described below are only some embodiments, and other drawings can be obtained by those skilled in the art without creative labor. In the drawings:
[0024] Figure 1 is the AFM morphology and 3D image of the surface of lepidolite before and after the action of the preferred example.
[0025] Figure 2 is the AFM morphology and 3D image of the surface of quartz before and after the action of the preferred example.
[0026] Figure 3 is the AFM morphology and 3D image of the surface of feldspar before and after the action of the preferred example.
[0027] Figure 4 is the contact angle of the three minerals before and after the action of the preferred example.
[0028] It should be noted that these drawings and written descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION
[0029] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments will be clearly and completely described below with reference to the drawings of the embodiments of the present application. The following embodiments are used to illustrate the present application, but not to limit the scope of the present application.
[0030] The example of the present application provides a combined collector, which comprises a glycine amphoteric collector, an amine cationic collector and an inhibitor.
[0031] Example 1
[0032] The 2 parts by mass of dodecylamine and 0.2 parts by mass of hydrochloric acid are mixed at room temperature, 400 parts by mass of water is added, and stirred at a speed of 250 r / min for 5 min, 1 part by mass of N-lauroylsarcosine sodium, 0.3 parts by mass of water glass and 600 parts by mass of water are further added, and stirred at a speed of 2500 r / min for 5 min to obtain a combined collector solution. The pure minerals of lithium mica, quartz and feldspar are crushed and ground to -75+38 μm, the ball-milled samples are mixed with water at room temperature respectively, and 40 mL of 5% mass percent pulp is prepared, the mixing time is 2 min, then 70 mg / L of the above combined collector solution is added to the pulp, and after 3 min, the flotation is scraped for 3 min to obtain the products in the flotation tank and the foam products. The recovery rates of lithium mica, quartz and feldspar are 98.7%, 33.8% and 34.0% respectively. The efficient separation of lithium mica from quartz and feldspar can be achieved. The AFM planar graph and 3D image of the surface of lithium mica, quartz and feldspar before and after the action of Example 1 are shown in Figs. Figure 1 、 2 3. The AFM test results show that after adding the combined collector, uniform size spots appear on the surface of lithium mica, and in the 3D image, the peaks are different in height. In addition, the surface height of lithium mica changes from 1.19 nm to 6.5 nm. The adsorption effect of the combined collector on lithium mica is the best, followed by feldspar, and the effect on quartz is the worst. The contact angles of the three minerals before and after the action of Example 1 are shown in Figure 4 . From the contact angle test results, it can be seen that the contact angle of lithium mica changes greatly after the adsorption of the combined collector, followed by feldspar, and finally quartz. Moreover, the contact angles of quartz and feldspar after adding the combined collector are both less than 45°, and the surfaces are still hydrophilic, while the surface of lithium mica presents hydrophobicity.
[0033] Example 2
[0034] This example is used to investigate the influence of the type of glycine amphoteric collector on the flotation performance of the combined collector. The implementation steps are exactly the same as those of Example 1, and the only difference is that 1 part by mass of N-lauroylsarcosine sodium is replaced by 1 part by mass of N-cocoyl glycine sodium. The flotation results are as follows: the recovery rates of lithium mica, quartz and feldspar are 97.5%, 38.1% and 39.0% respectively.
[0035] Example 3
[0036] This example is used to investigate the influence of the type of glycine amphoteric collector on the flotation performance of the combined collector. The implementation steps are exactly the same as those of Example 1, and the only difference is that 1 part by mass of N-lauroylsarcosine sodium is replaced by 1 part by mass of N-stearoyl glycine sodium. The flotation results are as follows: the recovery rates of lithium mica, quartz and feldspar are 96.1%, 36.5% and 37.5% respectively.
[0037] Example 4
[0038] This example is used to investigate the effect of inhibitor type on the flotation performance of the combined collector. The implementation steps are exactly the same as those of Example 1, the only difference being that 0.3 parts by mass of water glass is replaced by 0.3 parts by mass of sodium hexametaphosphate. The flotation results are: the recovery rates of lepidolite, quartz and feldspar are 94.3%, 33.2% and 33.1%, respectively.
[0039] Example 5
[0040] This example is used to investigate the flotation performance of the combined collector on artificial mixed ore. The implementation steps are exactly the same as those of Example 1, the difference being that the artificial mixed ore sample is prepared by mixing lepidolite, quartz and feldspar pure minerals at a ratio of 1:1:1 at room temperature, and then mixed with water to prepare a 40 mL pulp with a mass percentage of 5%, the pulp conditioning time being 2 min. Then, 70 mg / L of the above-mentioned combined collector solution is added to the pulp, and the flotation is carried out after 3 min of action and 3 min of froth scraping. The final lepidolite concentrate with a Li2O grade of 1.99% and a recovery rate of 92.3% is obtained.
[0041] Example 6
[0042] This example is used to investigate the flotation performance of the combined collector on lepidolite ore from a certain place in Hunan. At room temperature, 2 parts by mass of dodecylamine is mixed with 0.2 parts by mass of hydrochloric acid, and 400 parts by mass of water is added, and stirred at a speed of 250 r / min for 5 min. Then, 1 part by mass of N-lauroylsarcosine sodium, 0.3 parts by mass of water glass and 600 parts by mass of water are added, and the stirring is continued at a speed of 2500 r / min for 5 min to obtain a combined collector solution. The lepidolite ore from a certain place in Hunan (with a Li2O grade of 0.4%) is crushed and ground to 75% passing 75 μm, and then mixed with water at room temperature to prepare a 1000 mL pulp with a mass percentage of 30%. A closed-circuit operation of one roughing-two cleaning-one scavenging is carried out. In the roughing operation, the above-mentioned combined collector is used, and the combined collector dosage is 300 g / t, and the inhibitor water glass dosage is 500 g / t. In the scavenging operation, the above-mentioned combined collector is used, and the dosage is 150 g / t. In the cleaning operation, the inhibitor water glass is used, and the water glass dosage is 125-250 g / t. The final lepidolite concentrate with a Li2O grade of 1.81% and a recovery rate of 83.5% is obtained. Efficient separation of lepidolite from quartz and feldspar can be achieved.
[0043] Example 7
[0044] The embodiment is used for investigating the flotation performance of the combined collector on the fine slime of lepidolite in a certain place in Hunan. 2 parts by mass of dodecylamine is mixed with 0.2 parts by mass of hydrochloric acid, 400 parts by mass of water is added, stirring at a speed of 250 r / min for 5 min, then 1 part by mass of N-lauroylsarcosine sodium, 0.3 parts by mass of water glass and 600 parts by mass of water are added, and stirring is continued at a speed of 2500 r / min for 5 min to obtain a combined collector solution. The fine slime (Li2O grade of 0.22%, -25 μm accounting for 90%) of lepidolite in a certain place in Hunan is removed by flotation, and is mixed with water to prepare a 1000 mL pulp with a mass percentage of 20%. The pulp concentration is controlled at 25%, and a closed-circuit operation of one roughing-two cleaning-one scavenging is carried out. In the roughing operation, the combined collector is used, and the combined collector dosage is 300 g / t, and the water glass inhibitor is used in an amount of 500 g / t; in the scavenging operation, the combined collector is used, and the dosage is 150 g / t; and in the cleaning operation, the water glass inhibitor is used, and the water glass inhibitor dosage is 125-250 g / t. Finally, a lepidolite concentrate with a Li2O grade of 1.81% and a recovery rate of 73.5% is obtained. Efficient separation of lepidolite from quartz and feldspar can be achieved.
[0045] Comparative Example 1
[0046] The comparative example is used for investigating the flotation performance of dodecylamine and the combined collector on the artificial mixed ore. The implementation steps are completely same as those of Example 5, except that the combined collector solution is replaced by a 2 parts by mass of dodecylamine and 0.2 parts by mass of hydrochloric acid mixed solution. The artificial mixed ore sample is prepared by mixing lepidolite, quartz and feldspar pure minerals at a ratio of 1:1:1 at room temperature, and then mixed with water to prepare a 40 mL pulp with a mass percentage of 5%. Hydrochloric acid is used to adjust the ore pH to about 2, and the pulp mixing time is 2 min. Then, 70 mg / L of dodecylamine collector solution is added to the pulp, and the action time is 3 min. After 3 min of flotation and bubble scraping, the product in the flotation tank and the foam product are obtained. Finally, a lepidolite concentrate with a Li2O grade of 1.39% and a recovery rate of 82.3% is obtained. Compared with the combined collector of the application, the flotation index of dodecylamine is poorer.
[0047] Comparative Example 2
[0048] The comparative example is used for investigating the flotation performance of dodecylamine / sodium oleate combined reagent and the combined collector on the artificial mixed ore. The implementation steps are completely same as those of example 5, and the difference is that the combined collector solution is changed into a mixed solution of 2 parts by mass of dodecylamine, 0.2 parts by mass of hydrochloric acid and 2 parts by mass of sodium oleate. After the lithium mica, quartz and feldspar pure minerals are mixed in a ratio of 1:1:1 to prepare an artificial mixed ore sample, the sample is mixed with water, and a 40 mL pulp with a mass percentage of 5% is prepared. The pH of the ore is adjusted to about 3.5 by using hydrochloric acid, the slurry time is 2 min, then 70 mg / L of dodecylamine / sodium oleate combined collector solution is added to the pulp, and the flotation is carried out after 3 min of action, and the product in the flotation tank and the foam product are obtained after 3 min of scraping foam. Finally, the lithium mica concentrate with a Li2O grade of 1.51% and a recovery rate of 72.3% is obtained. Compared with the combined collector of the present application, the flotation index of the dodecylamine / sodium oleate combined reagent is poorer.
[0049] Comparative example 3
[0050] The present example is used for investigating the flotation performance of dodecylamine and the combined collector on the lithium mica ore in a certain place in Hunan. The implementation steps are completely same as those of example 6, and the difference is that the combined collector solution is changed into a mixed solution of 2 parts by mass of dodecylamine and 0.2 parts by mass of hydrochloric acid. Finally, the lithium mica concentrate with a Li2O grade of 1.01% and a recovery rate of 63.5% is obtained. Compared with the combined collector of the present application, the flotation index of dodecylamine is poorer.
[0051] Comparative example 4
[0052] The present example is used for investigating the flotation performance of dodecylamine / sodium oleate combined reagent and the combined collector on the lithium mica ore in a certain place in Hunan. The implementation steps are completely same as those of example 6, and the difference is that the combined collector solution is changed into a mixed solution of 2 parts by mass of dodecylamine, 0.2 parts by mass of hydrochloric acid and 2 parts by mass of sodium oleate. Finally, the lithium mica concentrate with a Li2O grade of 1.42% and a recovery rate of 53.5% is obtained. Compared with the combined collector of the present application, the flotation index of the dodecylamine / sodium oleate combined reagent is poorer.
[0053] The above only is the preferred embodiment of the present application, and does not limit the present application in any form, although the present application has been disclosed as above with the preferred embodiment, however, it is not used to limit the present application, any skilled person in the art can make some changes or modifications for the equivalent embodiments with the above-mentioned technical content without departing from the technical solution range of the present application, but any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present application, all still belong to the range of the present application.
Claims
1. A combination collector for neutral flotation of lepidolite ore, characterized in that, The combination collector is prepared from the following components: an amine cationic collector, a glycine amphoteric collector, and an inhibitor. The mass ratio of the amine cationic collector, the glycine amphoteric collector, and the inhibitor is (1.5-3):1:(0.2-0.8).
2. A combination collector for neutral flotation of lepidolite ores according to claim 1, characterized in that: The amine cationic collector is selected from one or any combination of dodecylamine, octadecylamine, and coconut amine.
3. A combination collector for neutral floatation of lepidolite ore as claimed in claim 1, wherein: The glycine-based amphoteric collector has the general formula RCONHCH2COO - M + wherein R is a C8-C18 alkyl or alkenyl group and M is a sodium, potassium or ammonium ion.
4. A combination collector for neutral floatation of lepidolite ore as claimed in claim 1, wherein: The glycine amphoteric collector is selected from one or any combination of N-lauroylsarcosine sodium, N-cocoyl glycine sodium, and N-stearoyl glycine sodium.
5. A combination collector for neutral floatation of lepidolite ore as claimed in claim 1, wherein: The inhibitor is selected from one or any combination of water glass and sodium hexametaphosphate.
6. A combination collector for neutral flotation of lepidolite ores according to claim 1, characterized in that: The mass ratio of the amine cationic collector, the glycine amphoteric collector, and the inhibitor is 2:1:0.
3.
7. A process for the preparation of the combined collector as claimed in any one of claims 1 to 6, characterized in that, The preparation process is as follows: 1.5-3 parts by mass of the amine cationic collector is mixed with 0.2-0.5 parts by mass of hydrochloric acid, 150-300 parts by mass of deionized water is added, and stirring is performed at a rotation speed of 250-350 r / min for 5-10 min; then 1 part by mass of the glycine amphoteric collector and (0.2-0.8) parts by mass of the inhibitor, and 150-300 parts by mass of deionized water are added, and stirring is continued for 5-10 min to obtain the combination collector solution.
8. Use of the combination collector of any one of claims 1-6 or prepared according to the method of claim 7 in the flotation recovery of lithium mica minerals under neutral to weak alkaline conditions.
9. Use according to claim 8, characterized in that, The flotation method comprises: crushing and grinding the lithium mica ore to a suitable particle size, adding the combination collector and the inhibitor, and performing roughing, cleaning, and scavenging after stirring and aeration to obtain a lithium mica concentrate.
10. Use according to claim 8 or 9, characterized in that, The total amount of the combination collector used is 300-800 g / t.