Collecting agent for flotation of spodumene, flotation reagent and preparation method of collecting agent and flotation reagent

Abstract

The invention belongs to the field of mineral flotation, and particularly relates to a collecting agent for flotation of spodumene, a flotation reagent and preparation and methods of the collecting agent and the flotation reagent, and the collecting agent is a compound with the structure of the formula 1 # imgabs0 #. Researches show that the compound with the special structure and shown in the formula 1 has excellent collecting capacity and selectivity on spodumene, and the good collecting capacity and selectivity can also be obtained even at the low temperature.

Description

Technical Field

[0001] The invention belongs to the technical field of mineral flotation, and in particular relates to the flotation field of spodumene. Background Art

[0002] Spodumene (LiAl(SiO3)2) is the main mineral source of lithium metal and its compounds in industry. Lithium is widely used in high-energy batteries, aerospace, ceramic manufacturing, and pharmaceuticals. With the rapid development of the new energy industry, the demand for lithium continues to increase, showing a significant growth trend. As one of the key mineral raw materials, the efficient recovery and comprehensive utilization of spodumene is of great significance to ensuring the supply of lithium resources.

[0003] At present, the prior art generally adopts flotation method to recycle spodumene, and the collector used is mostly based on contrast collector a, and is supplemented with other types of collectors for compounding. However, this type of traditional collector has problems such as low temperature intolerance, large dosage, poor selectivity and weak collection ability. At the same time, with the gradual decline of the quality of the raw ore, the actual lithium oxide recovery rate and the concentrate grade are both on the low side, resulting in a serious waste of spodumene resources. How to achieve efficient flotation separation of spodumene and silicate gangue minerals is still one of the technical problems to be solved in the current mineral processing field.

[0004] At present, in spodumene beneficiation plants, the commonly used process flow includes the following steps: first, the slurry is stirred for a long time and at high intensity under strong alkaline conditions; then, a depressant represented by water glass or lignin is added; then, an activator represented by calcium ions or magnesium ions is added; finally, a fatty acid collector is added to complete the flotation process. However, this process has the following problems: on the one hand, in a strong alkaline environment, silicate sludge will generate secondary water glass, which makes it difficult for suspended matter to settle naturally, thereby causing problems such as difficulty in tailings settling and limited wastewater reuse; on the other hand, the depressant used has poor selectivity and a large dosage, which is easy to inhibit part of the spodumene, thereby reducing its recovery rate; in addition, fatty acid collectors perform poorly in terms of low temperature resistance, collection capacity and selectivity, resulting in the spodumene concentrate grade failing to meet product standards, resulting in a serious waste of spodumene resources. Therefore, in order to achieve efficient utilization of spodumene resources, it is urgent to develop a new type of low-temperature resistant and efficient spodumene collector to effectively respond to the above challenges. Summary of the invention

[0005] In view of the problems faced by the existing spodumene flotation, the first object of the present invention is to provide a collector for flotation of spodumene, aiming to provide a collector with excellent spodumene collection ability and selectivity.

[0006] The second purpose of the present invention is to provide a method for preparing the collector.

[0007] The third object of the present invention is to provide a flotation reagent for spodumene containing the collector.

[0008] The fourth object of the present invention is to provide a method for flotation of spodumene.

[0009] A collector for flotation of spodumene is a compound having the structure of Formula 1;

[0010]

[0011] The R1 is a saturated carbon chain or a partially unsaturated carbon chain of C6 - C; 22 The R2 is a halogen (X) or a haloalkyl; M is H, Na, K or NH4.

[0012] Research of the present invention shows that the compound of Formula 1 with the special structure has excellent collecting ability and selectivity for spodumene, and can also obtain good collecting ability and selectivity even at low temperature and low dosage of the reagent.

[0013] In the present invention, the R1 is a straight-chain saturated carbon chain of C - C or a carbon chain with 1 - 3 unsaturated double bonds. Further, the R1 is a straight-chain carbon chain with 16 - 20 carbon atoms and having an unsaturated double bond at the 6 - 12 positions. 10 ~C 20 The combination and synergy of the halogenated R2 and the overall structure of the present invention are the key to improving the collecting ability and selectivity of spodumene at low temperature and low reagent dosage.

[0014] In the present invention, the R2 is a haloalkyl of C1 - C3; wherein, the halogen is at least one of fluorine, chlorine, bromine or iodine;

[0015] Preferably, the collector is a compound of Formula 1A;

[0016]

[0017]

[0018] In Formula 1A, R3 and R4 are H or X; the X is F, Cl, Br or I.

[0019] The present invention also provides a preparation method of the collector for flotation of spodumene, which is obtained by condensation of Formula 2 and Formula 3;

[0020]

[0021] R5 is OH or X; R1, R2, M are the same as in Formula 1. The X is F, Cl, Br or I.

[0022] As an alternative, the R5 in Formula 2 can be X.

[0023] The molar ratio of Formula 3 to Formula 2 can be 1:1 to 1.1.

[0024] In the present invention, a deacidifying agent is also allowed to be added during the condensation reaction. The deacidifying agent can be an alkaline component such as triethylamine, ammonia water, sodium carbonate, etc. The pH during the condensation reaction is controlled at 9 to 11.

[0025] The present invention also provides a flotation reagent for spodumene, which includes the collector described in the present invention and also includes other flotation reagents; the other flotation reagents include at least one of a pH regulator, an activator, a foaming agent, and an inhibitor.

[0026] Furthermore, the other flotation reagents include a pH regulator and an activator.

[0027] The pH regulator can be any acidic or alkaline component for adjusting the pH.

[0028] In the present invention, the activator includes at least one of water-soluble calcium salts such as calcium chloride, calcium chlorate, calcium carbonate, calcium ammonium phosphate, and calcium lactate.

[0029] The present invention also provides a method for flotation of spodumene. The mineral to be selected containing spodumene and the flotation reagent are mixed for rough selection to obtain a rough selection concentrate enriched with spodumene.

[0030] In the present invention, during the rough selection process, the dosage of the collector is 150 to 600 g / t; further, it can be 300 to 500 g / t. In the present invention, due to the innovative use of the collector of Formula 1, it can obtain excellent spodumene collecting ability and selectivity even at a lower dosage of the collecting reagent.

[0031] Preferably, the dosage of the activator is 100 to 400 g / t; further, it can be 150 to 250 g / t. The present invention can also obtain excellent spodumene collecting ability and selectivity at a low dosage of the reagent.

[0032] In the present invention, the pH during the rough selection process is 6.5 to 8; further, it can be 6.8 to 7.5. The present invention can perform flotation under neutral and near-neutral conditions, which is beneficial for controlling process wastewater and facilitating industrial implementation.

[0033] In the present invention, the temperature during the rough selection process is 0 to 40 °C, and further is 1 to 15 °C. The flotation reagent described in the present invention can meet the application requirements of a wide temperature range. Especially for the low-temperature flotation scenario, it can achieve better effects than the prior art.

[0034] In the present invention, the rough selection concentrate is subjected to cleaning treatment to obtain a cleaned concentrate of spodumene. During the cleaning process of the present invention, no flotation reagent needs to be added.

[0035] Preferably, the preliminarily selected tailings are scavenged. In the present invention, the dosage of the scavenging agent can be 30-60% of the dosage of the flotation agent used in the rough selection.

[0036] Beneficial effects

[0037] 1. The compound with the structure of Formula 1 involved in the present invention is used as a collector for spodumene flotation for the first time, realizing the efficient separation of spodumene from silicate gangue minerals under low-temperature conditions, and improving the grade and recovery rate of Li2O in the final spodumene concentrate.

[0038] Compared with the existing conventional fatty acid collectors, the collector of Formula 1 described in the present invention can still obtain better spodumene collecting ability and selectivity at lower dosages and lower flotation temperatures.

[0039] 2. The preparation process of the collector involved in the present invention is simple, the raw materials are widely sourced and easily obtainable, and it has the characteristics of being non-toxic, harmless, having strong low-temperature resistance and wide adaptability. At the same time, the dosage is small, showing significant application value in actual production.

[0040] 3. The collector involved in the present invention exhibits excellent collecting performance and selectivity in a neutral environment. Even without adding inhibitors, good separation effects can still be achieved; this not only helps to improve the separation efficiency, but also has a positive promoting effect on subsequent tailings sedimentation, tail water treatment and recycling. Description of the drawings

[0041] Figure 1 1H NMR and 13C NMR spectra of the acidification product; among them, (a) is the 1H NMR spectrum; (b) is the 13C NMR spectrum;

[0042] Figure 2 Infrared spectrum of the collector of Formula 1A;

[0043] Figure 3 Flotation flow chart used in Example 1; Detailed implementation manners

[0044] The technical solutions of the present invention will be clearly and comprehensively described below in conjunction with the drawings in the embodiments of the present invention. It should be noted that the described embodiments are only partial examples of the present invention, not all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments provided by the present invention without creative work shall fall within the protection scope of the present invention. In addition, unless otherwise specifically stated, various raw materials, reagents, instruments and equipment involved in the present invention can be purchased through the market or prepared according to existing technologies.

[0045] An optional preparation method of the collector of Formula 1 described in the present invention includes the following steps:

[0046] Step (1) - Acylation reaction:

[0047] Mix R1-COOH and PCl3 at a molar ratio of 1:0.9 - 1.5, control the reaction temperature at 40 - 60 °C, and the reaction time at 2 - 4 h. Remove the lower layer of phosphorous acid by-products through liquid separation to obtain R1-COCl.

[0048] Step (2) - Condensation reaction:

[0049] Mix (with a molar ratio of 1:1 - 1.1 to R1-COOH) and water at a mass ratio of 1:8 - 16, then add the mixture to a four-necked flask. Slowly add the R1-COCl obtained in step (1) to the flask using a dropping funnel, and at the same time slowly add triethylamine to neutralize the hydrochloric acid generated during the reaction. Control the pH within the range of 9.0 - 11.0, and the dropping time within 0.5 - 1 h. After completion, continue the reaction for 3 - 5 h.

[0050] Step (3) - Acidification reaction:

[0051] Dropwise add 0.8 - 1.2 mol / L sulfuric acid to the mixture obtained in step (2) to adjust the pH of the reaction system to 1.0 - 3.0. An oily product will appear in the reaction mixture. Let it stand and cool at room temperature, then collect the oily product using a separating funnel. Finally, wash and dry the oily product.

[0052] Step (4) - Saponification reaction:

[0053] Mix the oily product obtained in step (3) with a basic oxide (such as sodium hydroxide, potassium hydroxide, ammonia water) at a molar ratio of 1:0.8 - 1.2, add the mixture to a single-necked flask, then add water with the same mass as the mixture and stir. Control the reaction temperature at 40 - 60 °C and the reaction time at 1 - 3 h. Dry the reaction product to finally obtain a solid collector with the structural formula of formula 1.

[0054] For example, as an optional scheme, the collector of formula 1 takes formula 1A as an example, and its preparation steps are as follows:

[0055]

[0056] Its optional specific synthesis process is as follows:

[0057] Mix 0.33 mol of formula 2A with phosphorus trichloride at a molar ratio of 1:1.2, add the mixture to a flask, control the reaction temperature at 50 °C, and the reaction time at 3 h. Remove the lower layer of phosphorous acid using a separating funnel, and the upper layer of smoking oily substance is the required acylation product.

[0058] Then, 0.33 mol of Formula 3A and water were mixed at a mass ratio of 1:10 and added to a four-necked flask. The acylation product obtained from the previous reaction was slowly added dropwise to the flask using a dropping funnel, while triethylamine was slowly added dropwise to neutralize the hydrochloric acid generated in the reaction, controlling the pH at about 10.0. The dropping time was 0.8 h, and after completion, the reaction continued for 4 h. 1.0 mol / L sulfuric acid was added dropwise to the obtained mixed solution to adjust the pH of the reaction system to about 2.0. The oily product that appeared was washed with water and dried to obtain an acidified product (the product in Formula 1A where Na is H, and the hydrogen spectrum and carbon spectrum are shown in Figure 1 ); The obtained oily product was mixed with sodium hydroxide at a molar ratio of 1:1 and added to a single-necked flask, and then water with the same mass as the mixture was added for stirring. The reaction temperature was controlled at 50 °C, and the reaction time was 2 h. The reaction product was dried to obtain the collector used in the flotation test (the collector of Formula 1A).

[0059] The infrared spectrum of the collector of Formula 1A is as shown in Figure 2 shown.

[0060] In the present invention, the collector of Formula 1 described in the present invention can be used to perform flotation treatment on spodumene by means of conventional flotation means. For example, the optional flotation steps are as follows:

[0061] The low-grade pegmatite spodumene ore was subjected to grinding treatment, and a pH regulator (sodium carbonate and sodium hydroxide) was added to adjust the pulp, obtaining a pulp with a grinding fineness of -0.074 mm particle size accounting for 55% - 65%; The pulp was added to the flotation cell for strong stirring, and after standing, the fine mud was removed; The pH value of the pulp was adjusted to 6.5 - 8.0, then an activator (such as calcium chloride) was added to the pulp, and then at least one collector of Formula 1 structure was added for flotation; The flotation process includes roughing, cleaning, and scavenging carried out in sequence;

[0062] The dosage of the pH regulator is 300 - 1000 g / t. The dosage of the activator in the roughing process is 100 - 400 g / t, and the dosage of the collector is 150 - 600 g / t;

[0063] The "g / t" described in the present invention refers to the number of grams of the reagent required to be added per ton of spodumene raw ore treated.

[0064] Example 1

[0065] This collector was applied to a certain ultra-low-grade spodumene ore in Henan, where the grade of Li2O was 0.73%. The main target mineral of this lithium mineral was spodumene, and there were also a small amount of lepidolite and amblygonite. The main gangue minerals were feldspar, quartz, mica, etc. The collector described in the present invention was used for flotation of spodumene, and its process flow was as shown in Figure 3As shown below. The specific operation steps are as follows: The raw ore is first subjected to crushing and ball milling to make the particle size reach 60% with a particle size of 0.074 mm. Subsequently, the ground pulp is added to the flotation cell, and strong stirring is carried out for 10 minutes. Then it is left standing for 7 minutes, and the fine mud and bottom pulp are separated by siphoning. Then an appropriate amount of clear water is added to the bottom pulp, and a flotation test is carried out in the flotation cell. For this low-grade spodumene ore, a flotation process flow of one roughing, one scavenging, and three cleaning is adopted, and the pulp temperature is controlled at about 10 °C. The specific operation is as follows: In a single roughing operation, a regulator is added in sequence to maintain the pulp pH value at about 7.0 (stirring for 3 minutes), calcium chloride 200 g / t (stirring for 3 minutes), and a collector 400 g / t (stirring for 5 minutes), and then a 4-minute flotation process is carried out; In a single scavenging operation, calcium chloride 100 g / t (stirring for 2 minutes) and a collector 200 g / t (stirring for 3 minutes) are added in sequence, and a 3-minute flotation is carried out; No reagents are added in the three cleaning operations, only stirring for 2 minutes and flotation for 3 minutes are carried out respectively, and finally a lithium concentrate product is obtained, and the middlings are returned to the previous process in sequence. The flotation results are shown in Table 1. According to the data analysis in Table 1, the grade of Li2O in the lithium concentrate reaches 4.07%, and the recovery rate is 70.82%. This result fully shows that the collector adopted in the present invention still exhibits remarkable flotation performance for ultra-low-grade spodumene ore even under low-temperature conditions.

[0066] Example 2

[0067] In this example, the preparation process of the collector is the same as that in Example 1. This example uses a low-grade spodumene ore in Xinjiang as the raw material, and the grade of Li2O in the sample is 0.95%. The main target mineral of this lithium mineral is spodumene, and the main gangue minerals are feldspar, quartz, mica, etc. The dosage of the activator in the roughing process is 180 g / t, the dosage of the collector is 350 g / t, the pH of flotation is 7.5, no reagents are added in the cleaning, and the scavenging is 45% of the dosage of the roughing reagents; Other flotation operation processes are the same as those in Example 1.

[0068] The flotation results are shown in Table 1. It can be seen from Table 1 that the grade and recovery rate of Li2O in the lithium concentrate reach 5.64% and 79.22% respectively. The results show that under low-temperature conditions, the collector adopted in the present invention has remarkable flotation performance for low-grade spodumene ore.

[0069] Example 3

[0070] In this example, the preparation process of the collector is the same as that in Example 1. In this example, a spodumene ore with a relatively low grade in Sichuan is used as the raw material, and the grade of Li2O in the sample is 1.22%. The main target mineral of this lithium mineral is spodumene, and the main gangue minerals are feldspar, quartz, mica, etc. The dosage of the activator in the roughing process is 220 g / t, the dosage of the collector is 420 g / t, the pH of flotation is 6.8, no reagent is added in the cleaning process, and the scavenging is 55% of the reagent dosage in the roughing; other flotation operation processes are the same as those in Example 1. As can be seen from Table 1, the grade and recovery rate of Li2O in the lithium concentrate are as high as 6.38% and 82.60% respectively. The results show that in a low-temperature environment, the collector used in the present invention has very remarkable flotation performance for low-grade spodumene ore.

[0071] Comparative Example 1

[0072] Compared with Example 1, the difference is only that the comparative collector a is used as the collector, and the dosage of the comparative collector a is increased. For example, in the first roughing: comparative collector a 1500 g / t; in the first scavenging: comparative collector a 750 g / t; other operations and parameters are the same as those in Example 1; the test results are shown in Table 1. According to the data analysis in Table 1, the grade and recovery rate of Li2O in the lithium concentrate are only 3.35% and 45.34% respectively, which indicates that the flotation effect of the comparative collector a as the collector on ultra-low-grade spodumene ore is significantly lower than that of the collector used in the present invention.

[0073] Comparative Example 2

[0074] Compared with Example 2, the difference is only that the comparative collector a is used as the collector, and the dosage of the comparative collector a is increased. For example, in the first roughing: comparative collector a 1500 g / t; in the first scavenging: comparative collector a 750 g / t; other operations and parameters are the same as those in Example 2; the test results are shown in Table 1. As can be seen from Table 1, when the comparative collector a is used as the collector, the grade of Li2O in the lithium concentrate is only 4.18%, and the recovery rate is only 50.02%. This result shows that there is a significant gap in the flotation effect of the comparative collector a on low-grade spodumene ore compared with the collector used in the present invention.

[0075] Comparative Example 3

[0076] Compared with Example 3, the difference is only that the comparative collector a is used as the collector, and the dosage of the comparative collector a The dosage is increased. For example, in the first rough selection: compared with collector a, 1500 g / t; in the first scavenging: compared with collector a, 750 g / t; other operations and parameters are the same as in Example 3; the test results are shown in Table 1. It can be seen from Table 1 that when using the comparative collector a as the collector, the grade of Li2O in the lithium concentrate is only 4.86%, and the recovery rate is only 52.93%. The above results show that compared with the collector used in the present invention, the comparative collector a has significant deficiencies in the flotation of spodumene ores with lower grades.

[0077] Comparative Example 4

[0078] Compared with Example 1, the difference is only that the comparative collector b is used as the collector, and other operations and parameters are the same as in Example 1; the test results are shown in Table 1. It can be seen from Table 1 that when using the comparative collector b as the collector, the grade of Li2O in the lithium concentrate is 3.65%, and the recovery rate is 57.78%. The results show that compared with the collector used in the present invention, there is still a certain gap in the effect of the comparative collector b in the flotation of ultra-low grade spodumene ores.

[0079] Table 1 Flotation test results of examples and comparative examples (10 °C)

[0080]

[0081]

[0082] Through the comparative analysis of the examples and comparative examples, it can be found that the collector prepared by the present invention exhibits more excellent low-temperature resistance performance. At the same time, this collector shows stronger collecting ability and higher selectivity for spodumene. It can obtain better collecting ability and selectivity at lower dosages. Moreover, it has good universality for different types of spodumene ores, and can obtain excellent collecting ability effects under low temperature and low reagent consumption.

[0083] The above content only describes the embodiments of the present invention, but does not mean a limitation on the scope of patent protection of the present invention. Professionals in the relevant technical fields should recognize that the present invention can be adjusted and modified in various ways. Under the core idea and basic principles of the present invention, any improvements, equivalent substitutions, and solutions directly or indirectly applied to other relevant technical fields based on the content of the specification and drawings should be included in the scope of patent protection of the present invention.

Claims

1. A collector for flotation of spodumene, characterized in that: is a compound having a structure of Formula 1; The R1 is C6~C 22 A saturated carbon chain or a partially unsaturated carbon chain; R2 is a halogen or a halogenated alkyl; M is H, Na, K or NH4.

2. The collector for flotation spodumene as claimed in claim 1, wherein The R1 is C 10 ~C 20 A straight saturated carbon chain or a carbon chain with 1 to 3 unsaturated double bonds; The R2 is a C1-C3 halogen alkyl group; wherein the halogen is at least one of fluorine, chlorine, bromine or iodine; Preferably, the collector is a compound of formula 1A; In Formula 1A, R3 and R4 are H or X; and X is F, Cl, Br or I.

3. A method for preparing a collector for flotation spodumene according to claim 1 or 2, characterized in that: It is obtained by condensing formula 2 and formula 3; R5 is OH or X; R1, R2, and M are the same as in Formula 1.

4. A flotation agent for flotation of spodumene, characterized in that: The collector according to claim 1 or 2 also includes other flotation agents; the other flotation agents include at least one of a pH regulator, an activator, a frother, and an inhibitor.

5. The flotation agent for flotation spodumene according to claim 4, characterized in that: The other flotation reagents include a pH regulator and an activator; wherein the activator includes at least one of water-soluble calcium salts such as calcium chloride, calcium chlorate, calcium carbonate, calcium ammonium phosphate, and calcium lactate.

6. A method for flotation of spodumene, characterized in that: The mineral to be selected containing spodumene and the flotation agent according to any one of claims 4 to 5 are mixed for roughing, so as to obtain a roughing concentrate enriched with spodumene.

7. The method for flotation of spodumene as claimed in claim 6, characterized in that: In the roughing process, the amount of collector used is 150-600 g / t; more preferably 300-500 g / t; Preferably, the amount of the activator used is 100-400 g / t.

8. The method for flotation of spodumene as claimed in claim 6, characterized in that: The pH during the roughing process is 6.5-8.

9. The method for flotation of spodumene as claimed in claim 6, characterized in that: The temperature during the roughing process is 0 to 40°C, and further 1 to 15°C.

10. The method for flotation of spodumene according to claim 6, characterized in that: The rougher concentrate is subjected to beneficiation treatment to obtain spodumene beneficiated concentrate; Preferably, the rougher tailings are subjected to scavenging treatment.

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