Cationic amine collecting agent as well as preparation method and application thereof

Abstract

The invention discloses a cationic amine collecting agent which has the following structure: # imgabs0 #. The invention further discloses a preparation method of the cationic amine collecting agent and application of the cationic amine collecting agent in lepidolite flotation, an organic synthesis method is applied, a group-carboxyl group in an anionic collecting agent is introduced into the cationic amine collecting agent, and the cationic amine collecting agent is obtained. The novel collecting agent for lithium ore flotation is designed and synthesized, higher activity and selectivity are achieved in the aspect of target mineral collection, and the concentrate grade and the recovery rate of lithium ore can be remarkably improved.

Description

Technical Field

[0001] The invention relates to a cationic amine collector, a preparation method and application thereof. Background Art

[0002] Lithium occupies a pivotal position in today's world. It is the lightest metal element with unique chemical properties. In the energy field, lithium is a key component of lithium-ion batteries, providing powerful power support for various mobile devices, electric vehicles and energy storage systems. As the global demand for clean energy continues to grow, the importance of lithium has become increasingly prominent, and it has become an important force in promoting energy transformation. As the main source of lithium, the importance of lithium ore is self-evident. Abundant lithium ore resources can ensure the country's energy security and strategic needs. The development of lithium mines can not only drive the development of related industries and create a large number of employment opportunities, but also inject new impetus into economic growth.

[0003] In the mining and processing of lithium ore, flotation reagents play a vital role. Suitable flotation reagents can effectively improve the recovery rate and grade of lithium ore and reduce production costs. It can selectively adsorb on the surface of lithium minerals, making them hydrophobic and thus separating them from other minerals.

[0004] Cationic amine flotation agents have unique advantages in lithium ore flotation. They have a high collection capacity for lithium minerals and can float lithium minerals in complex ore systems. By rationally selecting and using amine flotation agents, the flotation efficiency and quality of lithium ore can be greatly improved, providing a strong guarantee for the efficient development and utilization of lithium resources.

[0005] However, lithium ore amine collectors have poor selectivity and are sensitive to water quality, and often need to be mixed with anionic collectors in actual production applications. Summary of the invention

[0006] The main purpose of the present invention is to provide a cationic amine collector, a preparation method and application thereof, aiming to solve the above technical problems.

[0007] To achieve the above object, the present invention provides a method for preparing a cationic amine collector, which specifically comprises:

[0008] Add compound A dropwise to compound B, stir at 0°C under argon for 1 hour, return to room temperature, and stir at room temperature for 2 hours to obtain compound C; then use ethyl acetate, saturated saline, saturated NaHCO3 aqueous solution and deionized water to dry the reaction mixture over anhydrous sodium sulfate column before use in the next reaction;

[0009] At 0°C and argon, a solution of compound C was added to ultra-dry CH2Cl2, and BOC2O was gradually added to protect the amino group of compound C; the solution was gradually heated to room temperature and stirred overnight, the reaction mixture was concentrated in vacuo, and the resulting reaction solution was purified by flash column chromatography using a hexane / AcOEt gradient to obtain compound D as a colorless oil;

[0010] Compound D was placed in a dry reactor in a glove box, NaIO4 and RuCl3 were added thereto, and then a mixture of AcOEt / MeCN / H2O was added in batches, and stirred at room temperature for 3 h. After the reaction, isopropanol was added to quench the reaction;

[0011] The reaction solution was first filtered on a celite pad, the filtrate was concentrated in vacuo, the aqueous phase was extracted with AcOEt, the combined organic extracts were washed with brine, dried over Na2SO4, concentrated in vacuo, and flash column chromatographed on SiO2 using a n-hexane / AcOEt gradient to give compound E as a colorless oil;

[0012] Compound E was dissolved in 4 mol / L hydrochloric acid and dioxane was added. The mixture was stirred at room temperature under argon for 2 h. The reaction mixture was cooled to 0°C and diluted with Et2O. The precipitate was filtered, washed with cold Et2O, and dried in vacuo to obtain carboxylic acid F as a white solid.

[0013] Wherein, the chemical structure formula of compound A is:

[0014]

[0015] The general chemical structure formula of compound B is:

[0016]

[0017] The general chemical structure formula of compound C is:

[0018]

[0019] The general chemical structure formula of compound D is:

[0020]

[0021] The general chemical structure formula of compound E is:

[0022]

[0023] The general chemical structure formula of compound F is:

[0024]

[0025] in:

[0026] R1 is alkane, alkene, or alkyne;

[0027] R2 is an alkane, an alkene, an alkyne, a benzene ring and its derivatives.

[0028] In addition, the present invention also provides a cationic amine collector, wherein the cationic amine collector F is a compound having the following chemical structural formula or its chemical isomer or salt thereof:

[0029]

[0030] in:

[0031] R1 is alkane, alkene, or alkyne;

[0032] R2 is an alkane, an alkene, an alkyne, a benzene ring and its derivatives.

[0033] In one embodiment, the compound A1 is And the compound B is

[0034] When the corresponding compound F is

[0035]

[0036] The compound A1 is And the compound B is

[0037]

[0038] When the corresponding compound F is

[0039]

[0040] The compound A1 is And the compound B is

[0041]

[0042] When the corresponding compound F is

[0043]

[0044] The compound A1 is And the compound B is When the corresponding compound F is

[0045]

[0046] In addition, the present invention also provides an application of a cationic amine collector in the flotation of lepidolite. The cationic amine collector is applied in the flotation process of lepidolite.

[0047] In the technical solution of the present invention, the carboxyl group in the anionic collector is introduced into the cationic amine collector by using an organic synthesis method, and a new collector for lithium ore flotation is designed and synthesized. The new collector has higher activity and selectivity in collecting target minerals, and can significantly improve the concentrate grade and recovery rate of lithium ore. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0050] Furthermore, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in the field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0051] The present invention provides a method for preparing a cationic amine collector, comprising:

[0052] Add compound A dropwise to compound B, stir at 0°C under argon for 1 hour, return to room temperature, and stir at room temperature for 2 hours to obtain compound C; then use ethyl acetate, saturated saline, saturated NaHCO3 aqueous solution and deionized water to dry the reaction mixture over anhydrous sodium sulfate column before use in the next reaction;

[0053] At 0°C and argon, a solution of compound C was added to ultra-dry CH2Cl2, and BOC2O was gradually added to protect the amino group of compound C; the solution was gradually heated to room temperature and stirred overnight, the reaction mixture was concentrated in vacuo, and the resulting reaction solution was purified by flash column chromatography using a hexane / AcOEt gradient to obtain compound D as a colorless oil;

[0054] Compound D was placed in a dry reactor in a glove box, NaIO4 and RuCl3 were added thereto, and then a mixture of AcOEt / MeCN / H2O was added in batches, and stirred at room temperature for 3 h. After the reaction, isopropanol was added to quench the reaction;

[0055] The reaction solution was first filtered on a celite pad, the filtrate was concentrated in vacuo, the aqueous phase was extracted with AcOEt, the combined organic extracts were washed with brine, dried over Na2SO4, concentrated in vacuo, and flash column chromatographed on SiO2 using a n-hexane / AcOEt gradient to give compound E as a colorless oil;

[0056] Compound E was dissolved in 4 mol / L hydrochloric acid and dioxane was added. The mixture was stirred at room temperature under argon for 2 h. The reaction mixture was cooled to 0°C and diluted with Et2O. The precipitate was filtered, washed with cold Et2O, and dried in vacuo to obtain carboxylic acid F as a white solid.

[0057] Wherein, the chemical structure formula of compound A is:

[0058]

[0059] The general chemical structure formula of compound B is:

[0060]

[0061] The general chemical structure formula of compound C is:

[0062]

[0063] The general chemical structure formula of compound D is:

[0064]

[0065] The general chemical structure formula of compound E is:

[0066]

[0067] The general chemical structure formula of compound F is:

[0068]

[0069] in:

[0070] R1 is alkane, alkene, or alkyne;

[0071] R2 is an alkane, an alkene, an alkyne, a benzene ring and its derivatives. In this embodiment, the synthesis route of compound F is as follows:

[0072]

[0073] In an optional embodiment, R1 in compound F can be methyl, ethyl, propyl, butyl, pentane, etc. or a benzene ring. R2 can be methyl, ethyl, propyl, butyl, pentane, etc. or a benzene ring.

[0074] Exemplarily, the compound A1 is And the compound B is

[0075] When the corresponding compound F is

[0076]

[0077] The compound A1 is And the compound B is

[0078]

[0079] When the corresponding compound F is

[0080]

[0081] The compound A1 is And the compound B is

[0082]

[0083] When the corresponding compound F is

[0084]

[0085] The compound A1 is And the compound B is When the corresponding compound F is

[0086]

[0087] The structure of compound F is similar to that of oleic acid except that it contains a quaternary amine and a primary amine. Compound F is similar to N-dodecyl-1,3-propylenediamine except that it contains a carboxyl group. Therefore, cationic collector N-dodecyl-1,3-propylenediamine and anionic collector oleic acid were selected as the comparison group to compare the flotation performance of the three reagents.

[0088] The anionic collector can be selected from one or a mixture of sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate, fatty acid methyl ester sulfonic acid, sodium olefin sulfonate, oxidized paraffin soap, tall oil, peroxy fatty acid soap and rosin acid, cyclohexane acid soap, tall oil, peroxy fatty acid soap, salicylic acid hydroxamic acid, and benzoic acid hydroxamic acid.

[0089] The cationic collector can be selected from one or a mixture of dodecylamine, tetradecylamine, hexadecylamine, coconut amine, dodecyltrimethylammonium chloride, etc.

[0090] The flotation effects of the new collector, oleic acid collector, and N-dodecyl-1,3-propylenediamine collector are compared below. See Implementation Case 1 for further explanation.

[0091] The raw ore sample this time comes from the lithium mica ore sample in Yichun City, Jiangxi Province. According to the ICP test of Jiuling Research Institute, the Li2O grade of the raw ore is 0.73% (that is, the Li2O content in the raw ore is 0.73%).

[0092] Example 1

[0093] The large pieces of lithium mica are broken into pieces, and the broken pieces are put into a jaw crusher for crushing. The crushed mineral powder is sieved and sieved, and the unbroken small pieces are put into the crusher for crushing again. The crushed mineral powder is measured by a laser particle size analyzer, and the proportion of 200 mesh is measured to be 65.8%.

[0094] Weigh a certain weight of lithium mica ore respectively, pour it into three flotation tanks after crushing, stir it evenly for 5-20 minutes at room temperature and a stirring speed of 1200r / min, add the combined inhibitor, and stir it again.

[0095] Finally, the novel collector (compound F) prepared by the present invention, oleic acid collector and N-dodecyl-1,3-propylenediamine collector were added, and the stirring speed was adjusted from 1200 r / min to 1650 r / min. After stirring for 1-10 minutes, the air inlet valve was opened, and a proper amount of foam was generated on the water surface. The foam was scraped and collected with a scraper.

[0096] According to the experimental process of one coarse-one fine-one sweep, flotation was carried out with oleic acid collector and N-dodecyl-1,3-propylenediamine collector.

[0097] The collected lithium mica concentrate was dried in an oven overnight, collected and mixed, and sent for testing of the concentrate grade (i.e., the mass fraction of lithium compounds in the concentrate) and calculation of the lithium recovery rate (i.e., the percentage of lithium compounds obtained in the concentrate to the lithium compounds in the original ore). The results are shown in the table below.

[0098]

[0099] Table 1 Concentrate grade and lithium recovery rate of different collectors

[0100] From Table 1, we can see that the collection ability of N-dodecyl-1,3-propylenediamine collector is stronger than that of oleic acid collector, and the concentrate grade of the new collector is higher than that of N-dodecyl-1,3-propylenediamine collector.

[0101] The reason for this phenomenon is that amine substances are surfactants. When the oleic acid collector is switched to an amine collector, it can be observed in the experiment that the foam in the flotation tank increases, but the foam is too stable and still does not break up in the collector.

[0102] Excessive stable foam can carry with it other impurity minerals, soil and dust, resulting in a lower concentrate grade, as shown in Table 1.

[0103] We added carboxyl groups to the new collectors. The oxygen atoms in the carboxylic acid groups can form coordination bonds with metal ions on the surface of lepidolite to cause chemical adsorption. This chemical adsorption is stronger than electrostatic adsorption, and can more firmly adsorb carboxylic acid reagents on the surface of lepidolite, enhance the adsorption stability of reagents on the mineral surface, and improve the flotation recovery rate and concentrate grade of lepidolite.

[0104] Implementation Case 2

[0105] The novel collector prepared by the invention can achieve the effect of oleic acid collector and N-dodecyl-1,3-propylenediamine collector at a small dosage.

[0106] Weigh a certain weight of lepidolite ore respectively, pour it into the flotation tank after crushing, stir for 5-20 minutes, add inhibitor, and stir again. Add 300g / t of the new collector prepared by the present invention, and follow the experimental process of one coarse, one fine, and one sweep.

[0107] Repeat the above operation, add 1200g / t of oleic acid collector and N-dodecyl-1,3-propylenediamine collector respectively, and carry out flotation strictly according to the above stirring time and scraping time.

[0108] The collected lepidolite concentrate was dried in an oven overnight, collected and mixed, and sent for testing of concentrate grade and calculation of lithium recovery. The results are shown in the table below.

[0109]

[0110] Table 2 Concentrate grade and lithium recovery rate after flotation with different collector dosages

[0111] From the data in Table 2, it can be seen that the new collector has higher activity and selectivity in capturing target minerals. It can accurately interact with the mineral surface at a relatively low dosage to achieve effective separation of minerals and gangue, indicating that its molecular structure or mechanism of action may be more conducive to chemical bonding and adsorption with the target mineral surface, thereby efficiently floating out the target mineral.

[0112] The flotation effect of 300g / t new collector is similar to or even better than that of 1200g / t oleic acid collector and N-dodecyl-1,3-propylenediamine collector, which means lower reagent cost and less collector usage. In subsequent tailings treatment and other links, the impact of residual reagent on the environment will be relatively smaller.

[0113] In summary, the lepidolite flotation reagent containing the collector of the present invention has good selectivity, strong collecting ability, and lower reagent dosage.

[0114] In addition, the cationic amine collector provided by the present invention is the above-mentioned compound F, and the chemical formula of compound F is as follows:

[0115]

[0116] in:

[0117] R1 is alkane, alkene, or alkyne;

[0118] R2 is an alkane, an alkene, an alkyne, a benzene ring and its derivatives.

[0119] In summary, when the cationic amine collector provided by the present invention is applied to the flotation of lepidolite, it can greatly increase the collection effect, and the flotation process is more stable and efficient.

[0120] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for preparing a cationic amine collector, characterized in that: The preparation method of the cationic amine collector comprises: Add compound A dropwise to compound B, stir at 0°C under argon for 1 hour, return to room temperature, and stir at room temperature for 2 hours to obtain compound C; then use ethyl acetate, saturated saline, saturated NaHCO3 aqueous solution and deionized water to dry the reaction mixture over anhydrous sodium sulfate column before use in the next reaction; At 0°C and argon, a solution of compound C was added to ultra-dry CH2Cl2, and BOC2O was gradually added to protect the amino group of compound C; the solution was gradually heated to room temperature and stirred overnight, the reaction mixture was concentrated in vacuo, and the resulting reaction solution was purified by flash column chromatography using a hexane / AcOEt gradient to obtain compound D as a colorless oil; Compound D was placed in a dry reactor in a glove box, NaIO4 and RuCl3 were added thereto, and then a mixture of AcOEt / MeCN / H2O was added in batches, and stirred at room temperature for 3 h. After the reaction, isopropanol was added to quench the reaction; The reaction solution was first filtered on a celite pad, the filtrate was concentrated in vacuo, the aqueous phase was extracted with AcOEt, the combined organic extracts were washed with brine, dried over Na2SO4, concentrated in vacuo, and flash column chromatographed on SiO2 using a n-hexane / AcOEt gradient to give compound E as a colorless oil; Compound E was dissolved in 4 mol / L hydrochloric acid and dioxane was added. The mixture was stirred at room temperature under argon for 2 h. The reaction mixture was cooled to 0°C and diluted with Et2O. The precipitate was filtered, washed with cold Et2O, and dried in vacuo to obtain carboxylic acid F as a white solid. Wherein, the chemical structure formula of compound A is: The general chemical structure formula of compound B is: The general chemical structure formula of compound C is: The general chemical structure formula of compound D is: The general chemical structure formula of compound E is: The general chemical structure formula of compound F is: in: R1 is alkane, alkene, or alkyne; R2 is an alkane, an alkene, an alkyne, a benzene ring and its derivatives.

2. A cationic amine collector, characterized in that: The cationic amine collector F is a compound having the following chemical structural formula or its chemical isomer or salt: in: R1 is alkane, alkene, or alkyne; R2 is an alkane, an alkene, an alkyne, a benzene ring and its derivatives.

3. The cationic amine collector according to claim 2, characterized in that: The compound A1 is And the compound B is When the corresponding compound F is The compound A1 is And the compound B is When the corresponding compound F is The compound A1 is And the compound B is When the corresponding compound F is The compound A1 is And the compound B is When the corresponding compound F is 4. Application of a cationic amine collector in lepidolite flotation, characterized in that: The cationic amine collector as claimed in claim 2 is used in the flotation process of lepidolite.

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