Lithium mica flotation collector, and preparation method and application thereof

Abstract

The application provides a lithium mica flotation collector and a preparation method and application thereof, and relates to the technical field of mineral flotation. The preparation method of the lithium mica flotation collector comprises the following steps: S1, uniformly mixing methanol and concentrated sulfuric acid to obtain solution A; S2, adding modified salicylhydroxamic acid to the solution A and uniformly mixing to obtain solution B; S3, adding water, sulfonated oleic acid and fatty alcohol polyoxyethylene ether to the solution B and uniformly mixing to obtain solution C, and heating and stirring the solution C to obtain the lithium mica flotation collector. The lithium mica flotation collector realizes effective flotation of lithium mica and improves the recovery rate of lithium mica.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mineral flotation, in particular to a lepidolite flotation collector and a preparation method and application thereof. BACKGROUND

[0002] With the increasing global attention to clean energy, new energy industries such as electric vehicles and energy storage systems have developed rapidly. As a key energy storage component in these fields, the demand for lithium-ion batteries has grown explosively. As one of the important sources of lithium resources, the study of lepidolite ore is a necessary requirement to meet the growing demand for lithium. For example, a certain amount of lithium element is contained in the lithium-ion battery required by an ordinary electric vehicle, and the rich lithium resources in lepidolite ore can provide guarantee for battery production.

[0003] Lithium is considered a strategic resource in modern industry. Countries have realized the importance of lithium resources, not only in the energy field, but also in many high-tech fields such as aerospace and electronics. The traditional supply of lithium resources mainly depends on salt lake brine and spodumene, but with the rapid growth of market demand, these resources are facing problems such as increasing mining difficulty, rising cost and gradual scarcity. Lepidolite ore is relatively widely distributed, which can alleviate the situation of tight supply of lithium resources to a certain extent. Through the study of lepidolite ore, more efficient beneficiation and extraction processes can be developed to expand the supply channel of lithium resources. There are differences in mineral structure, physical and chemical properties between lepidolite and spodumene, which requires collectors with different selectivity and collecting ability. The design and formula of the collector need to be adjusted accordingly for different minerals to achieve the best flotation effect and improve the overall utilization efficiency of resources. SUMMARY

[0004] Based on the technical problems existing in the background art, the present application provides a lepidolite flotation collector and a preparation method and application thereof.

[0005] The preparation method of the lepidolite flotation collector provided by the present application comprises the following steps:

[0006] S1, uniformly mixing methanol and concentrated sulfuric acid to obtain solution A;

[0007] S2, adding modified salicylhydroxamic acid to solution A and mixing uniformly to obtain solution B;

[0008] S3, adding water, sulfonated oleic acid and fatty alcohol polyoxyethylene ether to solution B and mixing uniformly to obtain solution C, and heating and stirring solution C to obtain the lepidolite flotation collector.

[0009] The prepared lithium mica flotation collector has stable properties, and through the synergistic effect of different reagents, effective flotation of lithium mica is realized, and the recovery rate of lithium mica is improved.

[0010] Preferably, in S1, the mass ratio of methanol to concentrated sulfuric acid is (2-4):1.

[0011] After mixing the methanol and concentrated sulfuric acid in a certain mass ratio, the solubility is better, which is beneficial to the subsequent reaction.

[0012] Preferably, in S2, the content of modified salicylhydroxamic acid in solution B is 40-80 g / L.

[0013] Preferably, in S2, the preparation method of modified salicylhydroxamic acid comprises the following steps: dissolving salicylhydroxamic acid in a solvent, adding acetic anhydride and concentrated sulfuric acid, heating and stirring uniformly, cooling to room temperature, adding a pH buffer solution to adjust the pH to neutral, washing and separating the organic phase, drying and evaporating to obtain modified salicylhydroxamic acid.

[0014] By esterification reaction, the acetyl group in acetic anhydride is introduced into the modified salicylhydroxamic acid molecule, which can change its chemical structure and properties. This modification can enhance the selectivity and collecting ability of modified salicylhydroxamic acid to specific minerals, and improve the flotation effect.

[0015] More preferably, the solvent is selected from one or more of toluene, cumene, propyl alcohol, and isopropyl alcohol.

[0016] More preferably, the mass-volume ratio of salicylhydroxamic acid to solvent, acetic anhydride, and concentrated sulfuric acid is (80-120):(100-300):50:(1-10).

[0017] More preferably, the heating temperature is 80-150 DEG C, and the heating time is 6-10 h.

[0018] More preferably, the stirring speed is 200-500 r / min.

[0019] More preferably, the pH buffer solution is a sodium hydroxide solution.

[0020] More preferably, the washing detergent is selected from one or more of saturated brine and ethyl acetate.

[0021] Preferably, in S3, the mass ratio of water, sulfonated oleic acid, and fatty alcohol polyoxyethylene ether is (1-3):1:1.

[0022] Controlling the mass ratio within a certain range helps to improve the collecting ability, in which sulfonated oleic acid dissociates anions in the ore pulp, and the anions can be adsorbed on the surface of the lithium mica with positive charge through electrostatic action. The electrostatic adsorption can increase the negative charge density of the mineral surface and improve the electrostatic attraction between the mineral and the bubble.

[0023] Preferably, in the S3, the content of the modified salicylhydroxamic acid in the solution C is 40-80 mg / L.

[0024] Preferably, in the S3, the heating temperature is 40-80 DEG C, and the heating time is 10-60 min.

[0025] The heating can improve the solubility in the solution and make the reaction more sufficient, and controlling the heating temperature can make the reaction proceed at a more ideal rate. Too high temperature can cause an increase in side reactions, decomposition of reactants or deterioration of products, while too low temperature can make the reaction rate too slow, affecting the production efficiency. Controlling the reaction time can ensure that the reactants are fully converted into products. Too short time can cause incomplete reaction and reduce the yield, while too long time can waste energy and time, and even can cause decomposition of products or occurrence of side reactions.

[0026] The application further provides a lithium mica flotation collector prepared by the preparation method.

[0027] The application further provides application of the lithium mica flotation collector prepared by the preparation method in lithium mica ore flotation, comprising the following steps:

[0028] S1, after grinding the lithium mica ore, adding water to make slurry, adding gangue mineral inhibitor and collector for once roughing and three times of cleaning to obtain lithium concentrate and middlings;

[0029] S2, after regrinding the middlings, adding water to make slurry, adding gangue mineral inhibitor and collector for once roughing and twice scavenging to obtain lithium concentrate and gangue minerals.

[0030] The lithium mica flotation collector prepared by the application can be used in the lithium mica ore flotation, and the lithium mica flotation collector is matched with the processes of grinding, slurry making, staged grinding and staged flotation, so that the selective separation between the lithium mica and the gangue minerals such as feldspar and quartz can be effectively realized.

[0031] Preferably, in the S1, the grinding is performed to a particle size of-0.074 mm content of 40%-60%.

[0032] Controlling the particle size of the ground lithium mica ore within a certain range helps the mineral to achieve partial monomer dissociation and does not cause overgrinding; this makes the target mineral and gangue mineral better separated, improving the effect of subsequent beneficiation operations such as flotation.

[0033] Preferably, in S1 and S2, the pulp conditioning is such that the solid content is 40%-60%.

[0034] The solid content within a certain range helps to form a relatively stable flotation froth, so that the fluidity and stability of the ore pulp reach a good balance.

[0035] Preferably, in S1 and S2, the pH value is adjusted to 8-9 during the pulp conditioning process using sodium hydroxide.

[0036] Preferably, in S1 and S2, the gangue mineral depressant is selected from one or more of sodium silicate, sodium humate, and sodium hexametaphosphate.

[0037] Preferably, in S1, the amount of gangue mineral depressant used is 500-700 g / t.

[0038] Controlling the amount of gangue mineral depressant within a certain range helps to inhibit the floating of gangue minerals; for some gangue minerals that coexist with the target mineral and are easily mixed into the concentrate during flotation, such as quartz and feldspar, the depressant can selectively adsorb on the surface of the gangue mineral, making it hydrophilic and remaining in the ore pulp, thereby improving the selectivity of flotation and ensuring the grade of the concentrate.

[0039] Preferably, in S1, the first roughing operation is: 500-700 g / t of gangue mineral depressant, 300-400 g / t of collector, stirring time of 3-10 min, and flotation time of 3-10 min.

[0040] Preferably, in S1, the three times of cleaning operation is: stirring time of 1-5 min, and flotation time of 1-5 min.

[0041] After one roughing operation, most of the valuable minerals can be quickly separated from the gangue, and the target mineral can be preliminarily enriched. Three times of cleaning operation can further purify and finely process the concentrate obtained by roughing. Each cleaning operation can remove more impurities and associated minerals, continuously increasing the content of target minerals in the concentrate, thereby significantly improving the grade of the mineral.

[0042] Preferably, in S2, the grinding is performed to a particle size of -0.074 mm content of 70%-80%.

[0043] The granularity of -0.074 mm content of 70% to 80% means that the mineral particles are very fine, and at this granularity, the mineral can be more fully dissociated; this makes the separation of the target mineral and the gangue mineral more thorough, provides a good foundation for subsequent beneficiation operations, and greatly improves the selectivity and recovery rate of the flotation process.

[0044] Preferably, in S2, the amount of gangue mineral inhibitor is 200-400 g / t.

[0045] Some gangue minerals that have not been completely separated may still exist in the slurry at this stage, and controlling the amount of gangue mineral inhibitor within a certain range can more effectively inhibit the floating of the gangue minerals, improve the separation effect of the target mineral and the gangue mineral, and thus improve the recovery rate and concentrate grade of the scavenging.

[0046] Preferably, in S2, the first roughing operation is: 200-400 g / t of gangue mineral inhibitor, 200-400 g / t of collector, stirring time 1-5 min, and flotation time 1-5 min.

[0047] Preferably, in S2, the second scavenging operation is: 100-200 g / t of gangue mineral inhibitor, 100-200 g / t of collector for the first time, 50-100 g / t of gangue mineral inhibitor, 50-100 g / t of collector for the second time, stirring time 1-5 min, and flotation time 1-5 min.

[0048] The second scavenging can maximize the recovery of the target mineral lost in the roughing and cleaning processes. The scavenging operation can treat the tailings again to recover the target mineral with insufficient recovery or insufficient dissociation degree to the beneficiation process.

[0049] The beneficial effects of the present application are:

[0050] The present application provides a lithium mica flotation collector, which is prepared by using methanol and sulfuric acid as solution regulators, and cooperatively modifying salicylhydroxamic acid, sulfonated oleic acid and fatty alcohol polyoxyethylene ether, so as to achieve selective collection of lithium mica. By using a ball mill for pre-grinding, slurry preparation, dosing, and a process of staged flotation and regrinding of middlings, the separation of lithium mica from gangue minerals such as feldspar and quartz can be effectively realized, and the recovery rate of lithium mica is improved. There is a synergistic effect between sulfonated oleic acid and modified salicylhydroxamic acid, which can be adsorbed on the surface of lithium mica together, forming a more stable adsorption layer, and enhancing the hydrophobicity and floatability of the mineral. At the same time, sulfonated oleic acid can also interact with fatty alcohol polyoxyethylene ether, further improving the performance of the collector. The amount of collector used in the flotation process is relatively small, which successfully solves the problems of poor solubility and unsatisfactory collection effect of traditional lithium mica collectors, and can effectively improve the grade of lithium mica in the flotation concentrate.

[0051] Due to the characteristics of lithium mica, the collector of the present application contains specific chemical substances or functional groups, which can better interact with the surface of lithium mica. The collector specially designed for lithium mica can better adapt to the mineral characteristics of lithium mica, improve the flotation recovery rate and grade. Compared with traditional collectors, the amount of reagent and energy consumption in the flotation process can be reduced. The complex application can further enhance the performance of the collector, improve the flotation efficiency of lithium mica, and reduce the production cost. The collector of the present application focuses on the selectivity of lithium mica in design, which can effectively separate lithium mica from other minerals and improve the purity of the product. The collector of the present application has stronger selectivity for lithium mica, reduces the mixing of impurities, and improves the efficiency and quality of subsequent processing.

[0052] The lithium mica flotation collector and its preparation method and application provided by the present application provide a new technical means for the development and utilization of lithium mica resources. The present application expands the application range of the collector, which is not only suitable for specific lithium mica ores, but also can be adjusted and optimized according to different ore properties. The present application brings new development opportunities for the lithium mica flotation industry, and helps to improve the competitiveness of China in the field of lithium resource development. DETAILED DESCRIPTION

[0053] The technical solutions of the present application are described in detail through specific embodiments.

[0054] The materials, reagents and the like used in the following examples and comparative examples can be obtained from commercial channels unless otherwise specified.

[0055] Sulfonated oleic acid: Shandong Guohua Chemical Co., Ltd.

[0056] Fatty alcohol polyoxyethylene ether: Liaoning Kelong Fine Chemical Co., Ltd., CAS No. 71060-57-6.

[0057] Lepidolite ore raw material: raw ore containing lepidolite and gangue minerals in Yichun area, the grade of Li2O is 0.32%, which is the main mineral to be recovered, and exists in the form of independent mineral in lepidolite, and a small amount exists in the form of isomorphism in biotite and muscovite, SiO2 is the main gangue mineral, mainly existing in the form of quartz. The rest of the gangue minerals are mainly plagioclase, potassium feldspar, etc.

[0058] Example 1

[0059] A preparation method of a lepidolite flotation collector, comprising the following steps:

[0060] S1, uniformly mix methanol and concentrated sulfuric acid according to a mass ratio of 2:1 to obtain solution A;

[0061] S2, add modified salicylhydroxamic acid to solution A to obtain solution B, the concentration of modified salicylhydroxamic acid in solution A is 40g / L;

[0062] S3, add water, sulfonated oleic acid and fatty alcohol polyoxyethylene ether to solution B according to a mass ratio of 2:1:1, mix uniformly to obtain solution C, heat and stir solution C at 60℃ for 30min to obtain a lepidolite flotation collector, wherein the content of modified salicylhydroxamic acid in solution C is 40mg / L.

[0063] The preparation method of modified salicylhydroxamic acid comprises the following steps: 100g of salicylhydroxamic acid is dissolved in 200ml of toluene, 50ml of acetic anhydride and 5ml of concentrated sulfuric acid are added, the temperature is raised to 100℃, the stirring speed is adjusted to 300r / min, heating and stirring is carried out for 8h, the temperature is cooled to room temperature, a 10% sodium hydroxide solution is added to adjust the pH to 7, the reaction mixture is poured into a separatory funnel, washed with 100ml of saturated brine and 100ml of ethyl acetate in turn, the washing is repeated for 3 times, the organic phase is separated, dried with 20g of anhydrous sodium sulfate, the residual water is removed, the solvent is removed at 50℃ by a rotary evaporator, and modified salicylhydroxamic acid is obtained.

[0064] The application of the lepidolite flotation collector in lepidolite ore flotation comprises the following steps:

[0065] S1, the lepidolite ore is put into a ball mill for primary grinding treatment until the particle size is-0.074mm and the content is 50%, water is added to adjust the pulp concentration to 50%, sodium hydroxide is used to adjust the pH value of the ore pulp to 8.5, 600g / t of sodium silicate and 400g / t of the collector are added for primary roughing, the stirring time is 5min, the flotation time is 5min, the stirring time is 3min, and the flotation time is 3min for three times of cleaning operation, and the lithium concentrate and middlings are obtained.

[0066] S2, regrinding the middlings to a particle size of -0.074 mm content of 75%, adding water to adjust the ore mass percentage concentration to 50%, using sodium hydroxide to adjust the pH value of the ore slurry to 8.5, adding 300g / t sodium silicate, 300g / t collector for one roughing stirring time 3min, flotation time 3min; twice cleaning operation includes: the first cleaning 150g / t sodium silicate, 150g / t collector, the second cleaning 75g / t sodium silicate, 75g / t collector, stirring time 3min, flotation time 3min; get lithium concentrate, gangue minerals; using the closed circuit process of middlings step by step return.

[0067] After detection, the grade of the obtained lithium concentrate is 1.83%, and the recovery rate is 69.12%.

[0068] Example 2

[0069] A preparation method of a lepidolite flotation collector, comprising the following steps:

[0070] S1, mixing methanol and concentrated sulfuric acid uniformly according to a mass ratio of 2:1 to obtain solution A;

[0071] S2, adding modified salicylhydroxamic acid to solution A to obtain solution B, the concentration of modified salicylhydroxamic acid in solution A is 60g / L;

[0072] S3, adding water, sulfonated oleic acid and fatty alcohol polyoxyethylene ether to solution B according to a mass ratio of 2:1:1, mixing uniformly to obtain solution C, heating and stirring solution C at 60℃ for 30min to obtain a lepidolite flotation collector, wherein the content of modified salicylhydroxamic acid in solution C is 60mg / L.

[0073] The preparation method of modified salicylhydroxamic acid is the same as that of example 1.

[0074] The application of the lepidolite flotation collector in lepidolite ore flotation is different from that of example 1 only in that the collector is different, and the others are the same as those of example 1.

[0075] After detection, the grade of the obtained lithium concentrate is 2.03%, and the recovery rate is 72.31%.

[0076] Example 3

[0077] A preparation method of a lepidolite flotation collector, comprising the following steps:

[0078] S1, mixing methanol and concentrated sulfuric acid uniformly according to a mass ratio of 2:1 to obtain solution A;

[0079] S2, adding modified salicylhydroxamic acid to solution A to obtain solution B, the concentration of modified salicylhydroxamic acid in solution A is 80g / L;

[0080] S3, water, sulfonated oleic acid, fatty alcohol polyoxyethylene ether are added into solution B according to a mass ratio of 2:1:1, mixed uniformly to obtain solution C, and solution C is heated and stirred at 60 DEG C for 30 min to obtain a lithium mica flotation collector, wherein the content of the modified salicylhydroxamic acid in solution C is 80 mg / L.

[0081] The preparation method of the modified salicylhydroxamic acid is the same as that in Example 1.

[0082] The lithium mica flotation collector is applied in the flotation of lithium mica ore, and the difference from Example 1 is only that the collector is different, and the others are the same as those in Example 1.

[0083] It is detected that the grade of the obtained lithium concentrate is 1.91%, and the recovery rate is 70.22%.

[0084] Comparative Example 1

[0085] The lithium mica flotation collector is applied in the flotation of lithium mica ore, and the difference from Example 1 is only that the collector is different, and the others are the same as those in Example 1.

[0086] S1, the lithium mica ore is placed into a ball mill for once grinding treatment until the particle size is-0.074 mm and the content is 50%, water is added to adjust the pulp concentration to 50%, 600 g / t of gangue mineral inhibitor sodium silicate and 400 g / t of traditional lithium mica collector 8-1 (Jinjuyuan) are added, and once concentration stirring is performed for 5 min and flotation is performed for 5 min; three times of concentration operation stirring is performed for 3 min and flotation is performed for 3 min to obtain lithium concentrate and middlings;

[0087] S2, the middlings are re-ground to a particle size of-0.074 mm and the content is 75%, water is added to adjust the pulp concentration to 50%, 300 g / t of sodium silicate and 300 g / t of traditional lithium mica collector 8-1 (Jinjuyuan) are added, and once concentration stirring is performed for 3 min and flotation is performed for 3 min; two times of scavenging operation including: 150 g / t of sodium silicate and 150 g / t of collector are added for the first time of scavenging, 75 g / t of sodium silicate and 75 g / t of collector are added for the second time of scavenging, stirring is performed for 3 min, and flotation is performed for 3 min to obtain lithium concentrate and gangue minerals; a closed circuit process of returning the middlings step by step is adopted.

[0088] It is detected that the grade of the obtained lithium concentrate is 1.89%, and the recovery rate is 70.13%.

[0089] According to the above, the lithium mica flotation collector provided by the application realizes effective flotation of lithium mica and improves the recovery rate of lithium mica.

[0090] The above merely describes preferred specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art, according to the technical solution and inventive concept of the present application, makes equivalent replacement or change within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A process for the preparation of a lithium mica flotation collector, characterized in that, It comprises the following steps: S1, uniformly mixing methanol and concentrated sulfuric acid to obtain solution A; S2, adding modified salicylhydroxamic acid to solution A to obtain solution B; S3, adding water, sulfonated oleic acid and fatty alcohol polyoxyethylene ether to solution B to obtain solution C, and heating and stirring solution C to obtain lithium mica flotation collector; In S2, the preparation method of modified salicylhydroxamic acid comprises the following steps: dissolving salicylhydroxamic acid in a solvent, adding acetic anhydride and concentrated sulfuric acid, heating and stirring uniformly, cooling to room temperature, adjusting pH to neutral by adding pH buffer solution, washing and separating organic phase, drying and evaporating to obtain modified salicylhydroxamic acid.

2. The production method according to claim 1, characterized by, In S1, the mass ratio of methanol to concentrated sulfuric acid is 2-4:

1.

3. The preparation method according to claim 1, characterized in that, In the preparation of salicylhydroxamic acid, the mass-volume ratio of salicylhydroxamic acid to solvent, acetic anhydride, concentrated sulfuric acid is 80-120:100-300:50:1-10; the heating temperature is 80-150℃, and the heating time is 6-10h.

4. The method of claim 1, wherein, In S2, the content of modified salicylhydroxamic acid in solution B is 40-80g / L.

5. The preparation method according to claim 1, characterized in that, In S3, the mass ratio of water, sulfonated oleic acid and fatty alcohol polyoxyethylene ether is 1-3:1:1; the heating temperature is 40-80℃, and the heating time is 10-60min.

6. Use of the lithium mica flotation collector obtained by the production process according to any one of claims 1 to 5 in the flotation of lithium mica ores, characterized in that, It comprises the following steps: S1, after grinding and adding water to the lithium mica ore, adding gangue mineral inhibitor and collector for one roughing and three cleaning to obtain lithium concentrate and middlings; S2, after regrinding and adding water to the middlings, adding gangue mineral inhibitor and collector for one roughing and two scavenging to obtain lithium concentrate and gangue mineral.

7. Use according to claim 6, characterized in that, In S1, the grinding is to a particle size of-0.074mm content of 40%-60%; the dosage of gangue mineral inhibitor is 500-700g / t; the one roughing operation is: 500-700g / t of gangue mineral inhibitor, 300-400g / t of collector, stirring time of 3-10min, and flotation time of 3-10min.

8. Use according to claim 6, characterized in that, In S2, the grinding is to a particle size of-0.074mm content of 70%-80%; the dosage of gangue mineral inhibitor is 200-400g / t; the one roughing operation is: 200-400g / t of gangue mineral inhibitor, 200-400g / t of collector, stirring time of 1-5min, and flotation time of 1-5min; the two scavenging operation is: 100-200g / t of gangue mineral inhibitor and 100-200g / t of collector for the first scavenging, and 50-100g / t of gangue mineral inhibitor and 50-100g / t of collector for the second scavenging, stirring time of 1-5min, and flotation time of 1-5min.

9. Use according to claim 6, characterized in that, The gangue mineral inhibitor is selected from one or more of sodium silicate, sodium humate and sodium hexametaphosphate.