Combined collecting agent for direct flotation of lepidolite and application of combined collecting agent

Abstract

The invention discloses a combined collecting agent for direct flotation of lepidolite and application of the combined collecting agent. The combined collecting agent is formed by compounding hexadecylsulfonic acid sodium salt and lauryl amine according to the molar ratio of 1: 3-3: 1. And lepidolite ore samples to be separated and water are mixed and stirred to be uniform, flotation ore pulp is obtained, after the pH value of the ore pulp is adjusted to the required pH value, the combined collecting agent is added, direct flotation desilicication is conducted, and a lepidolite concentrate product is obtained. The combined collecting agent shows good selectivity and excellent separation performance when being applied to the field of direct flotation desilicication of lepidolite, and has the advantages that the agents are easy to obtain, the preparation process is simple, and the dosage of the agents is small.

Description

Technical Field

[0001] The invention belongs to the technical field of mineral flotation separation, relates to the separation and quality improvement of lepidolite ore, and specifically relates to a lepidolite positive flotation combined collector and application thereof. Background Art

[0002] In recent years, with the rapid development of the lithium battery industry, the global demand for lithium resources has continued to rise, and the competition for lithium resources has become increasingly fierce among countries around the world. Although my country is not short of lithium resources, due to the limitations of traditional separation technology, resource advantages have been difficult to play, and supply risks are prominent. For this reason, a large amount of imports are carried out, and the external dependence is as high as more than 60%. Therefore, the efficient development of lithium mineral resources is of great strategic significance.

[0003] Lepidolite is a lithium-containing clay mineral and an important component of lithium resources. At present, flotation is an important means of separating and upgrading lepidolite ores. Since lepidolite and its associated siliceous gangue minerals (such as feldspar, etc.) have similar surface physical and chemical properties and similar floatability, the flotation separation of minerals is difficult. Cationic collectors such as fatty amines are often used in industry to float lepidolite, but the separation effect is poor due to the poor selectivity of amine collectors and their sensitivity to mineral mud. Therefore, there is an urgent need to develop highly selective collectors to achieve efficient flotation separation of lepidolite and siliceous gangue minerals. Summary of the invention

[0004] In view of the problems of poor selectivity and separation efficiency in the flotation process of lepidolite when a single amine collector is used, the present invention provides a lepidolite positive flotation combined collector and application thereof. The separation effect is improved through the synergistic effect of the two collectors, and the flotation process is simple, so as to achieve the purpose of efficient lepidolite positive flotation desiliconization.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] In the first aspect, the present invention provides a lithium mica positive flotation combined collector, which is composed of sodium hexadecyl sulfonate and dodecylamine in a molar ratio of 1:3 to 3:1. Dodecylamine and sodium hexadecyl sulfonate in the combined collector component are respectively a cationic collector and an anionic collector, and the two collectors are electrically complementary and synergistic, which is specifically manifested in that the collectors with opposite electrical properties can produce a charge compensation effect, and molecular association is easy to occur. The combined collector is co-adsorbed on the surface of the target mineral lithium mica, has good selectivity, can selectively capture lithium mica minerals, and realize efficient flotation separation of lithium mica and siliceous gangue mineral feldspar.

[0007] In a second aspect, the present invention provides the use of the above-mentioned combined collector in the positive flotation desiliconization of lepidolite.

[0008] Specifically, the steps include:

[0009] Step 1: Grind

[0010] The raw lepidolite or the mixed mineral sample of lepidolite and feldspar is crushed and ground, and the ore sample with a particle size of less than 0.105 mm is obtained after screening;

[0011] Step 2: Mixing the slurry

[0012] The ore sample screened in step 1 is mixed with water, added into the flotation equipment, and stirred evenly to obtain a slurry with a mass concentration of 5 to 30%;

[0013] Step 3: Flotation

[0014] At room temperature, adjust the pH of the slurry to 3-11.5 and stir evenly; add the collector sodium hexadecyl sulfonate to the slurry with a pH of 3-11.5 and stir for 2 minutes; then add the collector dodecylamine and stir for 2 minutes before flotation separation.

[0015] In step 2, the flotation equipment is preferably a stirring flotation machine with a rotation speed of 1500-2000 r / min and a flotation time of 3-5 min.

[0016] In step 3, the stirring rate is 1500-2000 r / min, and the stirring time is 2-3 min.

[0017] In step 3, the pH value is preferably 5.

[0018] In step 3, the total amount of the combined collector sodium hexadecyl sulfonate and dodecylamine is preferably 3×10 - 4 mol / L~5×10 -4 mol / L.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention develops a combined collector of dodecylamine and sodium hexadecyl sulfonate for positive flotation desiliconization of lepidolite. The collectors sodium hexadecyl sulfonate and dodecylamine are added in sequence during the flotation process. Through the synergistic effect of the combined collectors, the lepidolite is selectively captured, and the efficient flotation separation of lepidolite and siliceous gangue mineral feldspar is achieved. Finally, a lepidolite concentrate with a lepidolite recovery rate of more than 95% and a Li2O grade of more than 4.0% can be obtained.

[0021] 2. The combined collector of dodecylamine and sodium hexadecyl sulfonate of the present invention is miscible with water, non-toxic and pollution-free, chemically stable, and has the advantages of simple preparation method, small dosage, good selectivity and high sorting efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1The present invention is a schematic diagram of a process flow of positive flotation desiliconization of lepidolite according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The following non-limiting embodiments may enable a person skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.

[0024] Unless otherwise specified, the reagents and materials described in the following examples can be obtained from commercial sources.

[0025] The ore samples in the following embodiments are artificial mixed ore samples prepared by mixing lepidolite and feldspar in a mass ratio of 1:1, wherein the lepidolite and feldspar are both taken from the lepidolite mining area in Jiangxi Province, and the sample particle size prepared after screening is 0.038-0.105 mm.

[0026] The XFGII hanging trough flotation machine used in the following examples was purchased from Jilin Province Prospecting Machinery Factory.

[0027] In the following examples, the collector dodecylamine was dissolved in water with hydrochloric acid in a molar ratio of 1:1 before use to prepare a 0.01-0.05 mol / L solution; the collector sodium hexadecyl sulfate was directly dissolved in water before use to prepare a 0.01-0.05 mol / L solution.

[0028] In the following Examples 1 to 5, a pH adjuster is used to adjust the pH value of the slurry. The acidic adjuster is hydrochloric acid with a concentration of 0.01 to 0.1 mol / L; the alkaline adjuster is sodium hydroxide with a concentration of 0.01 to 0.1 mol / L.

[0029] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Example 1

[0031] Step 1: Grind

[0032] The lithium mica and feldspar are crushed and ground, and after screening, the ore samples with a particle size of 0.038-0.105mm are obtained.

[0033] Step 2: Mixing the slurry

[0034] The mixed ore of lithium mica and feldspar and deionized water were added into the flotation equipment, mixed and stirred at a speed of 1500 r / min for 1 minute, and the slurry was adjusted to a slurry concentration of 5%.

[0035] Step 3: Flotation Separation

[0036] At room temperature, hydrochloric acid solution was added to the slurry to adjust the pH value of the slurry to 5.0, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 5.0.

[0037] Add the collector sodium hexadecyl sulfate to the slurry with a pH value of 5.0, stir for 2 minutes, and the flotation machine speed is 1500r / min. Then add the collector dodecylamine, mix and stir for 2 minutes at a speed of 1500r / min. The molar ratio of sodium hexadecyl sulfate to dodecylamine in the combined collector is 1:3, and the total amount of the combined collector is 4×10 -4 mol / L. Then flotation was carried out, and the foam was scraped every 10 seconds for 3 minutes. After the flotation, the foam product, i.e., concentrate, and the product in the tank, i.e., tailings, were dried and weighed respectively, and samples were taken for testing of Li2O grade, and the recovery rate was calculated. The recovery rate of lithium mica in the flotation concentrate was 58.44%, and the Li2O grade was 3.05%.

[0038] Example 2

[0039] Steps 1 and 2 are the same as steps 1 and 2 in Example 1.

[0040] Step 3: Flotation Separation

[0041] At room temperature, sodium hydroxide solution was added to the slurry to adjust the pH value of the slurry to 9.60, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 9.60.

[0042] Add the collector sodium hexadecyl sulfate to the slurry with a pH value of 9.6 and stir for 2 minutes. The speed of the flotation machine is 1500r / min. Then add the collector dodecylamine and mix and stir for 2 minutes at a speed of 1500r / min. The molar ratio of sodium hexadecyl sulfate to dodecylamine in the combined collector is 1:3, and the total amount of the combined collector is 4×10 -4 mol / L. Then flotation separation, scraping bubbles every 10s, scraping bubbles for 3min. After flotation, the foam product, i.e. concentrate, and the product in the tank, i.e. tailings, are dried and weighed respectively, and samples are taken for testing of Li2O grade, and the recovery rate is calculated. The recovery rate of lithium mica in the flotation concentrate is 60.51%, and the Li2O grade is 2.73%.

[0043] Example 3

[0044] Steps 1 and 2 are the same as steps 1 and 2 in Example 1.

[0045] Step 3: Flotation Separation

[0046] At room temperature, hydrochloric acid solution was added to the slurry to adjust the pH value of the slurry to 5.0, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 5.0.

[0047] Add the collector sodium hexadecyl sulfate to the pulp with a pH value of 5.0, stir for 2 minutes, and the flotation machine speed is 1500r / min. Then add the collector dodecylamine, mix and stir for 2 minutes at a speed of 1500r / min. The molar ratio of sodium hexadecyl sulfate to dodecylamine in the combined collector is 1:1, and the total amount of the combined collector is 4×10 -4 mol / L. Then flotation separation, scraping bubbles every 10s for 3min. After flotation, the foam product, i.e. concentrate, and the product in the tank, i.e. tailings, are dried and weighed respectively, and samples are taken for testing of Li2O grade, and the recovery rate is calculated. The recovery rate of lithium mica in the flotation concentrate is 69.89%, and the Li2O grade is 3.62%.

[0048] Example 4

[0049] Steps 1 and 2 are the same as steps 1 and 2 in Example 1.

[0050] Step 3: Flotation Separation

[0051] At room temperature, hydrochloric acid solution was added to the slurry to adjust the pH value of the slurry to 5.0, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 5.0.

[0052] Add the collector sodium hexadecyl sulfate to the pulp with a pH value of 5.0 and stir for 2 minutes. The speed of the flotation machine is 1500r / min. Then add the collector dodecylamine and mix and stir for 2 minutes at a speed of 1500r / min. The molar ratio of sodium hexadecyl sulfate to dodecylamine in the combined collector is 3:1, and the total amount of the combined collector is 4×10 -4 mol / L. Then flotation separation is performed, and the foam is scraped every 10 seconds for 3 minutes. After the flotation, the foam product, i.e., concentrate, and the product in the tank, i.e., tailings, are dried and weighed respectively, and samples are taken for testing of the Li2O grade, and the recovery rate is calculated. The recovery rate of lithium mica in the flotation concentrate is 98.12%, and the Li2O grade is 4.20%.

[0053] Example 5

[0054] Steps 1 and 2 are the same as steps 1 and 2 in Example 1.

[0055] Step 3: Flotation Separation

[0056] At room temperature, sodium hydroxide solution was added to the slurry to adjust the pH value of the slurry to 9.6, and the mixture was mixed and stirred at a speed of 1500 r / min for 1 min to obtain a slurry with a pH value of 9.6.

[0057] Add the collector sodium hexadecyl sulfate to the slurry with a pH value of 9.6 and stir for 2 minutes. The speed of the flotation machine is 1500r / min. Then add the collector dodecylamine and mix and stir for 2 minutes at a speed of 1500r / min. The molar ratio of sodium hexadecyl sulfate to dodecylamine in the combined collector is 1:1, and the total amount of the combined collector is 4×10 -4 mol / L. Then flotation separation, scraping bubbles every 10s, scraping bubbles for 3min. After flotation, the foam product, i.e. concentrate, and the product in the tank, i.e. tailings, are dried and weighed respectively, and samples are taken for testing of Li2O grade, and the recovery rate is calculated. The recovery rate of lithium mica in the flotation concentrate is 48.99%, and the Li2O grade is 2.54%.

[0058] Comparative Example 1

[0059] The difference between Comparative Example 1 and Example 4 is that only sodium hexadecyl sulfate was added as the collector, and the total amount of collector was 4×10 -4 mol / L.

[0060] The pulp was floated according to the method of Comparative Example 1, and the lithium mica recovery rate in the flotation concentrate was 77.61%, while the Li2O grade was only 2.87%.

[0061] Comparative Example 2

[0062] The difference between Comparative Example 2 and Example 4 is that only dodecylamine, a collector, is added, and the total amount of collector is 4×10 - 4 mol / L.

[0063] The pulp was floated according to the method of Comparative Example 2, and the lithium mica recovery rate in the flotation concentrate was 98.59%, while the Li2O grade was only 2.57%.

[0064] Compared with the use of sodium hexadecyl sulfonate or dodecylamine as a collector alone, the use of dodecylamine and sodium hexadecyl sulfonate as a combined collector can achieve a higher lepidolite recovery rate (greater than 95%) and significantly improve the Li2O grade of the flotation concentrate (greater than 4.20%).

[0065] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A combined collector for positive flotation of lepidolite, characterized in that: The invention is prepared by mixing sodium hexadecyl sulfonate and dodecylamine in a molar ratio of 1:3 to 3:

1.

2. Use of the combined collector according to claim 1 in the positive flotation desiliconization of lepidolite.

3. The use according to claim 2, characterized in that: The following steps are involved: Step 1: Grind The raw lepidolite or the mixed mineral sample of lepidolite and feldspar is crushed and ground, and the ore sample with a particle size of less than 0.105 mm is obtained after screening; Step 2: Mixing the slurry The ore sample screened in step 1 is mixed with water, added into the flotation equipment, and stirred evenly to obtain a slurry with a mass concentration of 5 to 30%; Step 3: Flotation At room temperature, adjust the pH of the slurry to 3-11.5 and stir evenly; add the collector sodium hexadecyl sulfonate to the slurry with a pH of 3-11.5 and stir for 2 minutes; then add the collector dodecylamine and stir for 2 minutes before flotation separation.

4. The use according to claim 3, characterized in that: In step 2, the flotation equipment is a stirring flotation machine with a rotation speed of 1500-2000 r / min and a flotation time of 3-5 min.

5. The use according to claim 3, characterized in that: In step 3, the stirring rate is 1500-2000 r / min, and the stirring time is 2-3 min.

6. The use according to claim 3, characterized in that: The pH value is 5.

7. The use according to claim 3, characterized in that: The total amount of the combined collector sodium hexadecyl sulfonate and dodecylamine is 3×10 -4 mol / L~5×10 -4 mol / L.

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