Reverse flotation collecting agent and preparation method and application thereof

Abstract

The invention relates to a reverse flotation collecting agent and a preparation method and application thereof, and belongs to the technical field of bauxite reverse flotation desilicication. The reverse flotation collecting agent has a chemical structural formula as shown in a formula (I): R1-NH-R2-NH2. In the formula (I), R1 and / or R2 comprises at least one of the following functional groups: a-CN3H4 functional group and a-SO3H functional group. A diamine group and-CN3H4 in the reverse flotation collecting agent can enhance the action with groups such as hydroxyl, silicon and oxygen on the surface of the aluminosilicate mineral, and the selectivity of the reverse flotation collecting agent is improved; the interaction between-SO3H and metal ions in hard water can be reduced, the hard water resistance is improved, the adaptability of the collecting agent in the hard water is improved, meanwhile, alkyl non-polar macromolecular chains in R1 and / or R2 strengthen the hydrophobicity of the surfaces of ore grains after the collecting agent acts, and the collecting capacity of the reverse flotation collecting agent is improved. Therefore, the reverse flotation collecting agent gives consideration to selectivity and adaptability to minerals.

Description

Technical Field

[0001] The present application relates to the technical field of bauxite reverse flotation desiliconization, and in particular to a reverse flotation collector and a preparation method and application thereof. Background Art

[0002] Bauxite reverse flotation desiliconization technology is a commonly used method in bauxite beneficiation. Its main purpose is to improve the grade of alumina and reduce the silicon content to meet the raw material requirements of alumina production. Compared with the direct flotation desiliconization technology, the reverse flotation desiliconization technology of bauxite has obvious advantages, especially when dealing with bauxite with a large difference in grindability between diaspore and silicate minerals, it can effectively avoid the mudding problem caused by over-grinding, reduce mechanical entrainment and reagent dosage, and comply with the flotation principle of "more suppression and less floating".

[0003] Bauxite reverse flotation collectors need to have a high degree of selectivity for useful minerals and gangue minerals in bauxite, but in practice it is often difficult to achieve ideal selectivity, resulting in the loss of useful minerals or excessive flotation of gangue minerals, and poor selectivity; some collectors have poor solubility and dispersibility in hard water and poor hard water resistance, which limits their application under specific water quality conditions. At the same time, some collectors may cause pollution to the environment during the preparation process and do not meet environmental protection requirements. Summary of the invention

[0004] The present application provides a reverse flotation collector and a preparation method and application thereof, in order to solve the following technical problem: how to improve the selectivity and adaptability of the reverse flotation collector to minerals.

[0005] In a first aspect, an embodiment of the present application provides a reverse flotation collector, wherein the reverse flotation collector has a chemical structure shown in formula (I):

[0006] R1-NH-R2-NH2

[0007] Formula (I)

[0008] In formula (I), R1 and / or R2 include at least one of the following functional groups: -CN3H4 functional group, -SO3H functional group.

[0009] Optionally, the carbon number of R1 is 2 to 10; and / or;

[0010] The carbon number of R2 is 2-5.

[0011] Optionally, the reverse flotation collector includes at least one of the following: N-decanedisulfonate ethylenediamine, N-methylguanidine pentamethylenediamine, N-butyl-2-sulfonate-1,3-propylenediamine, N-hexyl-3-guanidine-1,5-pentanediamine, N-(2-sulfonate)propylpropylenediamine, and N-ethylguanidine-2-sulfonate propylenediamine.

[0012] In a second aspect, an embodiment of the present application provides a method for preparing a reverse flotation collector according to any one of the embodiments of the first aspect, the method comprising:

[0013] Obtain diamine organic matter;

[0014] A -CN3H4 functional group and / or a -SO3H functional group are introduced into the diamine organic matter to obtain a reverse flotation collector.

[0015] Optionally, the diamine organic compound includes at least one of the following: ethylenediamine, pentamethylenediamine, and propylenediamine.

[0016] Optionally, the diamine organic compound is obtained, comprising:

[0017] The -NH2 functional group is introduced into the monoamine organic compound to obtain the diamine organic compound.

[0018] Optionally, the monoamine organic substance includes at least one of the following: ethanolamine, dimethylamine, n-propylamine, isopropylamine, n-pentylamine, and isopentylamine.

[0019] In a third aspect, an embodiment of the present application provides a method for reverse flotation desiliconization of bauxite, the method comprising:

[0020] Adjusting the pH value of the bauxite slurry;

[0021] An inhibitor and the reverse flotation collector described in any one of the embodiments of the first aspect are sequentially added to the bauxite slurry after pH adjustment to perform reverse flotation desiliconization to obtain a desiliconized slurry.

[0022] Optionally, the weight of particles with a particle size of less than 0.074 mm in the bauxite slurry is ≥ 75.0%.

[0023] Optionally, the end point pH of the pH adjustment is 4 to 10; and / or,

[0024] The inhibitor is added in an amount of 20 g / t dry ore to 100 g / t dry ore; and / or,

[0025] The reverse flotation desiliconization temperature is 15°C to 50°C; and / or,

[0026] The added amount of the reverse flotation collector is 300.0 g / t to 800.0 g / t of ore pulp.

[0027] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0028] The reverse flotation collector provided in the embodiment of the present application has a chemical structure shown in formula (I): R1-NH-R2-NH2. Formula (I) contains two amine groups in the molecular structure of the reverse flotation collector, which can provide more active sites to react with the mineral surface. The amine groups NH and NH2 can both produce strong physical adsorption with the surface of silicate minerals. The two amine groups are more likely to produce physical adsorption with the surface of silicate mineral particles, increase the hydrophobicity of silicate minerals, and thus enhance the collection capacity of the reverse flotation collector; R1 and / or R2 include at least one of the following functional groups: -CN3H4 functional group, -SO3H functional group. The nitrogen atom in the -CN3H4 functional group is negatively charged due to its large electronegativity. Through acid-base reaction, the reverse flotation collector It exists in the form of cations, while the surface charge of silicate minerals is negative, so that there is electrostatic attraction between the reverse flotation collector and the surface of silicate minerals, thereby enhancing the interaction between the reverse flotation collector and silicate minerals; the acidity of the -SO3H functional group enables the -SO3H functional group to form ionic bonds on the mineral surface, enhancing the interaction between the reverse flotation collector and the mineral surface, thereby improving the adsorption capacity and selectivity of the reverse flotation collector, while the -SO3H functional group maintains good solubility and dispersibility in water, which can reduce the influence of calcium and magnesium ions on the performance of the reverse flotation collector and enhance the hard water adaptability of the reverse flotation collector; therefore, the -CN3H4 functional group and / or the -SO3H functional group can enhance the collection capacity, selectivity and adaptability of the reverse flotation collector. In summary, the selectivity and adaptability of the reverse flotation collector to minerals are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0031] Figure 1 A schematic flow chart of a method for preparing a reverse flotation collector provided in an embodiment of the present application;

[0032] Figure 2 A schematic flow chart of a method for reverse flotation desiliconization of bauxite provided in an embodiment of the present application;

[0033] Figure 3 A flow chart of the test of "one roughing, one cleaning and one scavenging" for the method of reverse flotation desiliconization of bauxite provided in the embodiment of the present application;

[0034] Figure 4 This is a flow chart of the "one roughing, two cleanings, and one scavenging" test of the bauxite reverse flotation desiliconization method provided in the embodiments of the present application. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0036] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0037] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the description of the specification of the present application, the terms "include", "comprise", etc. refer to "including but not limited to". In this article, "and / or" describes the association relationship of the associated objects, indicating that there may be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A and B can be singular or plural. In this article, "at least one" refers to one or more, and "multiple" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can all represent: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0038] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0039] In a first aspect, an embodiment of the present application provides a reverse flotation collector, wherein the reverse flotation collector has a chemical structure shown in formula (I):

[0040] R1-NH-R2-NH2 Formula (Ⅰ)

[0041] In formula (I), R1 and / or R2 include at least one of the following functional groups: -CN3H4 functional group, -SO3H functional group.

[0042] In the embodiments of the present application, in view of the poor selectivity and poor adaptability of the existing bauxite reverse flotation collectors, the mineral components and the charged properties of the minerals in the slurry and the characteristics of the mineral cleavage planes are investigated by conducting mineral analysis on bauxite, and the diamines are obtained by introducing -NH2 into the monoamine compounds, and on this basis, -CN3H4 and -SO3H functional groups are introduced to obtain guanidine (sulfonic acid) diamine novel reverse flotation collectors. Compared with monoamine compounds, diamine compounds can provide more active sites to interact with the mineral surface due to the presence of two amine groups in the molecular structure, thereby enhancing the capture ability of the collector. This is because during the flotation process, the collector needs to form a stable adsorption layer with the mineral surface, and the diamine compounds can interact with the mineral surface more effectively due to having more active sites, thereby improving the capture efficiency; and the introduction of specific functional groups, such as -CN3H4 functional groups and / or -SO3H functional groups, can enhance the capture ability, selectivity and adaptability of the collector. Among them, the introduction of diamine groups and -CN3H4 in the reverse flotation collector can enhance the interaction with hydroxyl, silicon, oxygen and other groups on the surface of aluminosilicate minerals, and improve the selectivity of the reverse flotation collector; the introduction of -SO3H can reduce the interaction with metal ions in hard water, improve the hard water resistance, and improve the adaptability of the collector in hard water. At the same time, the hydrocarbon non-polar macromolecular chain in R1 and / or R2 strengthens the hydrophobicity of the surface of the mineral particles after the collector acts, and improves the collection capacity. Compared with conventional monoamines (such as fatty amines, alkylamines) and pyridine reverse flotation collectors, it has the advantages of high selectivity, low collector dosage, and strong adaptability. Therefore, through the design and optimization of functional groups, the adaptability and synergistic effect of the collector are improved.

[0043] The molecular structure of the reverse flotation collector contains two amine groups, NH and NH2, which can interact with the mineral surface and provide more active sites. The active sites are like "connection points" that can interact with specific areas on the mineral surface, increase the chances of the reverse flotation collector contacting and reacting with the mineral, and thus improve the selectivity of the reverse flotation collector. NH and NH2 can produce strong physical adsorption on the surface of silicate minerals based on intermolecular forces, especially van der Waals forces and electrostatic attraction between the lone pair of electrons of nitrogen atoms in the amine group and the active sites on the mineral surface or partially positively charged areas, and the presence of two amine groups further enhances the physical adsorption effect. The two amine groups can interact with different sites on the surface of mineral particles at the same time, making the adsorption more solid and covering a wider range. With the enhancement of physical adsorption, the properties of the mineral particle surface change, and the hydrophobicity of the mineral increases. In the reverse flotation process, mineral particles with good hydrophobicity are more likely to adhere to bubbles, and thus separated from the slurry with the help of bubble buoyancy, which directly enhances the collection capacity of the reverse flotation collector.

[0044] The nitrogen atom in the -CN3H4 functional group is negatively charged due to its high electronegativity. Electronegativity is the ability of an atom to attract electrons. The relatively high electronegativity of the nitrogen atom increases the density of the electron cloud around it, presenting a negative charge state. Under a specific acid-base environment, through the action of acid and base, the entire reverse flotation collector exists in the form of cations. Since the surface charge of silicate minerals is negative, according to the principle of mutual attraction of opposite charges in electrostatics, there is an electrostatic attraction between the positively charged reverse flotation collector (which is in the form of cations due to the related action of the -CN3H4 functional group) and the negatively charged silicate mineral surface. This electrostatic attraction can shorten the distance between the collector and the mineral, making it easier for the two to approach each other and act, thereby enhancing the interaction between the reverse flotation collector and the silicate mineral. For example, in a slurry system, this attraction can guide the collector to move and attach preferentially to silicate minerals, and has a stronger tendency to "capture" silicate minerals among many mineral particles.

[0045] The -SO3H functional group is acidic. When it comes into contact with the mineral surface, it can form ionic bonds with some ions or active sites on the mineral surface through chemical reaction processes such as losing protons. Ionic bonds are stronger chemical bonds. Compared with physical adsorption and other effects, they can more firmly connect the collector to the mineral surface, thereby significantly enhancing the interaction between the reverse flotation collector and the mineral surface. The -SO3H functional group maintains good solubility and dispersibility in water. Good solubility can ensure that the collector is evenly dispersed in the slurry solution, so that it can fully contact with the mineral particles, avoiding the situation where the local concentration is too high or too low and affects the collection effect. Good dispersibility can prevent the collector from agglomerating itself, ensuring that it exists in the form of a single molecule or a small molecular aggregate, so as to play a better role. At the same time, it can reduce the impact of calcium and magnesium ions on the performance of reverse flotation collectors. Under hard water conditions, a large amount of calcium and magnesium ions in the water are prone to adverse chemical reactions with the collector, such as forming precipitation or interfering with the normal adsorption functions of the collector. However, the -SO3H functional group can reduce this interference by virtue of its own characteristics, enhance the hard water adaptability of the reverse flotation collector, and enable the collector to work more stably and effectively in slurry environments with different water qualities, thus broadening its application range.

[0046] Therefore, the -CN3H4 functional group and the -SO3H functional group, through their respective mechanisms of action, enhance the interaction with the mineral surface, improve the adsorption capacity, enhance the selectivity, and improve the adaptability to different water qualities, thereby jointly enhancing the collection capacity, selectivity, and adaptability of the reverse flotation collector, and ultimately achieving the important goal of improving the selectivity of the reverse flotation collector for minerals, so that the target minerals can be more accurately separated from other impurity minerals in the reverse flotation process, which is of great significance for improving the quality and efficiency of mineral processing.

[0047] In some embodiments, the carbon number of R1 is 2 to 10; and / or;

[0048] The carbon number of R2 is 2-5.

[0049] In the embodiment of the present application, the number of carbon atoms of R1 can be 2 to 10, and the number of carbon atoms of R2 can be 2 to 5, which can make the reverse flotation collector have good selectivity. The number of carbon atoms of R1 and R2 is regulated to regulate the length of the carbon chain of the collector. This is because the length of the carbon chain has an important influence on the hydrophobic effect and spatial effect of the collector. The appropriate carbon chain length can enhance the interaction between the collector and the mineral surface and improve the flotation efficiency of the reverse flotation collector. If the number of carbon atoms of R1 is higher than 10 or the number of carbon atoms of R2 is higher than 5, the solubility of the reverse flotation collector may decrease, and the amount of reverse flotation collector may be increased; and the interaction between the collector molecules may be increased, and the adsorption capacity of the collector on the mineral surface may be reduced, thereby weakening the flotation effect; if the number of carbon atoms of R1 is lower than 2 or the number of carbon atoms of R2 is lower than 2, the hydrophobic effect of the collector may be insufficient, and the adsorption capacity of the collector on the mineral surface may be reduced, thereby reducing the flotation efficiency. Illustratively, the number of carbon atoms in R1 can be 2, 4, 5, 6, 7, 8, 9, 10, etc.; the number of carbon atoms in R2 can be 2, 4, 5, etc.

[0050] In some embodiments, the reverse flotation collector includes at least one of the following: N-decanedisulfonate ethylenediamine, N-methylguanidine pentamethylenediamine, N-butyl-2-sulfonate-1,3-propylenediamine, N-hexyl-3-guanidine-1,5-pentanediamine, N-(2-sulfonate)propylpropylenediamine, and N-ethylguanidine-2-sulfonate propylenediamine.

[0051] In the embodiment of the present application, the reverse flotation collector can be N-decanesulfonic acid ethylenediamine (HO3S-C 10 H 20 -NH-C2H4-NH2),

[0052] N-Methylguanidinopentanediamine

[0053] Butyl-2-sulfonyl-1,3-propylenediamine

[0054] N-Hexyl-3-guanidino-1,5-pentanediamine N-(2-sulfonic acid)propylpropylenediamine N-ethylguanidino-2-sulfonic acid propanediol

[0055] amine The use of the above reverse flotation collector can improve the efficiency and selectivity of flotation desiliconization, enhance the hard water resistance, increase the aluminum-silicon ratio of the concentrate, reduce the dosage of reagents, and improve resource utilization.

[0056] In a second aspect, the present application provides a method for preparing the reverse flotation collector described in any one of the embodiments of the first aspect, Figure 1A schematic diagram of a method for preparing a reverse flotation collector provided in an embodiment of the present application; see Figure 1 , the method comprising:

[0057] S1, obtaining diamine organic matter;

[0058] S2. Introducing a -CN3H4 functional group and / or a -SO3H functional group into the diamine organic matter to obtain a reverse flotation collector.

[0059] In some embodiments, the diamine organic compound includes at least one of the following: ethylenediamine, pentamethylenediamine, and propylenediamine.

[0060] In some embodiments, the step of obtaining a diamine organic compound comprises:

[0061] The -NH2 functional group is introduced into the monoamine organic compound to obtain the diamine organic compound.

[0062] In some embodiments, the monoamine organic compound includes at least one of the following: ethanolamine, dimethylamine, n-propylamine, isopropylamine, n-pentylamine, and isopentylamine.

[0063] In an embodiment of the present application, a diamine compound is synthesized by a monoamine compound to increase the collection capacity of the reverse flotation collector, and then different functional groups -CN3H4 functional groups and / or -SO3H functional groups are introduced into the diamine compound to improve the selectivity and adaptability of the reverse flotation collector. The diamine organic matter can be a combination of one or more of ethylenediamine, pentamethylenediamine, and propylenediamine; the monoamine organic matter can be a combination of one or more of ethanolamine, dimethylamine, n-propylamine, isopropylamine, n-pentylamine, and isopentylamine. Exemplarily, the preparation method of N-decanesulfonic acid ethylenediamine comprises: first dehydrogenating ethanolamine under the action of a catalyst to generate aldehyde, and then dehydrating the aldehyde with ammonia to obtain ethylenediamine; ethylenediamine and 11-oxodecane-1-sulfonic acid are subjected to an aldehyde condensation reaction to obtain N-decanesulfonic acid ethylenediamine.

[0064] The preparation method of the reverse flotation collector is realized based on the above-mentioned reverse flotation collector. The specific structure of the reverse flotation collector can refer to the above-mentioned embodiment. Since the preparation method of the reverse flotation collector adopts part or all of the technical solutions of the above-mentioned embodiment, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiment, which will not be described one by one here.

[0065] In a third aspect, the present application provides a method for reverse flotation desiliconization of bauxite. Figure 2 A schematic diagram of a method for reverse flotation desiliconization of bauxite provided in an embodiment of the present application; see Figure 2 , the method comprising:

[0066] S1', adjusting the pH value of the bauxite slurry;

[0067] S2', sequentially adding an inhibitor and the reverse flotation collector described in any one of the embodiments of the first aspect to the bauxite slurry after pH adjustment to perform reverse flotation desiliconization to obtain a desiliconized slurry.

[0068] In some embodiments, the weight of particles in the bauxite slurry having a particle size of < 0.074 mm is ≥ 75.0%.

[0069] In the embodiment of the present application, the above reverse flotation collector is applied to a method for reverse flotation desiliconization of bauxite. The desiliconized slurry is separated to obtain flotation concentrate and flotation tailings.

[0070] The weight of particles with a particle size of <0.074mm in the bauxite slurry can be ≥75.0%. Bauxite is usually a collection of multiple minerals, and different minerals coexist closely. Minerals are dissociated by grinding. When the weight of particles with a particle size of <0.074mm is ≥75.0%, silicon-containing minerals in bauxite can be better separated from aluminum minerals such as diaspore, and the mineral monomers are more fully dissociated, so that the reverse flotation collector can be more accurately adsorbed on the surface of silicon-containing minerals, which is conducive to the reverse flotation collector to act on the target mineral in a targeted manner to float it out, thereby improving the grade of bauxite. At the same time, when the proportion of fine particles is high, the specific surface area of ​​the mineral is increased, which greatly increases the contact opportunity between the mineral and the reverse flotation collector, exposes more active sites, and the reagent can be more effectively adsorbed on the mineral surface, enhancing the flotation effect. Illustratively, the weight of particles with a particle size of <0.074 mm in the bauxite slurry may be 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, etc.

[0071] In some embodiments, the endpoint pH of the pH adjustment is 4 to 10; and / or,

[0072] The inhibitor is added in an amount of 20 g / t dry ore to 100 g / t dry ore; and / or,

[0073] The reverse flotation desiliconization temperature is 15°C to 50°C; and / or,

[0074] The added amount of the reverse flotation collector is 300.0 g / t to 800.0 g / t of ore pulp.

[0075] In the embodiment of the present application, the endpoint pH of pH adjustment can be 4 to 10. The electrical properties of the surfaces of aluminum-containing minerals such as diaspore and silicon-containing minerals in the slurry are quite different. The surface of silicon-containing minerals is usually negatively charged, and the reverse flotation collector is mostly cationic, which is easier to adsorb on the surface of negatively charged silicon-containing minerals, which is conducive to selective flotation, thereby floating it out and realizing aluminum-silicon separation; at the same time, the stability and activity of the reverse flotation collector are better within the endpoint pH range, and it can maintain an appropriate degree of ionization, and it is easier to interact with the surface of the target mineral. If the endpoint pH is higher than 10 or the endpoint pH is lower than 4, the reverse flotation collector may be hydrolyzed, precipitated or lose activity, thereby affecting the flotation effect. Exemplarily, the endpoint pH of the pH adjustment can be 4, 5, 6, 7, 8, 9, 10, etc.

[0076] The amount of inhibitor added can be 20g / t dry ore to 100g / t dry ore. During the reverse flotation of bauxite, the role of the inhibitor is to cover or change the properties of the active sites on the surface of aluminum-containing minerals, thereby reducing their interaction with the reverse flotation collector and preventing them from floating out with silicon-containing minerals. If the amount of the inhibitor added is less than 20g / t dry ore, it may be difficult to completely suppress the aluminum-containing minerals, resulting in the mixing of aluminum-containing minerals into the foam product, reducing the grade of the bauxite concentrate; if the amount of the inhibitor added is higher than 100g / t dry ore, excessive suppression may occur, which will not only suppress the minerals that do not need to float, but also suppress the silicon-containing minerals that need to float, affecting the flotation effect. Exemplarily, the amount of the inhibitor added can be 20 g / t dry ore, 30 g / t dry ore, 40 g / t dry ore, 50 g / t dry ore, 60 g / t dry ore, 70 g / t dry ore, 80 g / t dry ore, 90 g / t dry ore, 100 g / t dry ore, etc. The inhibitor can be one or a combination of sodium hexametaphosphate, starch, dextrin, and cationic polyacrylamide.

[0077] The temperature of reverse flotation desiliconization can be 15°C to 50°C, and the solubility and selectivity of the collector will be improved, and it has strong adaptability. If the temperature of the reverse flotation desiliconization is lower than 15°C, the solubility of the collector may be reduced, and the amount of the collector may be increased; if the temperature of the reverse flotation desiliconization is higher than 50°C, the stability and selectivity of the collector may be affected, resulting in a decrease in the flotation effect. Exemplarily, the temperature of the reverse flotation desiliconization can be 15°C, 18°C, 20°C, 23°C, 25°C, 28°C, 30°C, 33°C, 35°C, 38°C, 40°C, 43°C, 45°C, 48°C, 50°C, etc.

[0078] The amount of the reverse flotation collector added can be 300.0 g / t slurry to 800.0 g / t slurry, which can obtain a higher aluminum concentrate recovery rate under the premise of ensuring a better aluminum concentrate grade, effectively float gangue minerals, and ensure the concentrate grade and aluminum-silicon ratio. Exemplarily, the amount of the reverse flotation collector added can be 300.0 g / t slurry, 350 g / t slurry, 400 g / t slurry, 450 g / t slurry, 500 g / t slurry, 550 g / t slurry, 600 g / t slurry, 650 g / t slurry, 700 g / t slurry, 750 g / t slurry, 800 g / t slurry, etc.

[0079] The method for reverse flotation desiliconization of bauxite is implemented based on the above-mentioned reverse flotation collector. The specific structure of the reverse flotation collector can refer to the above-mentioned embodiment. Since the method for reverse flotation desiliconization of bauxite adopts part or all of the technical solutions of the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0080] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for the unrecorded specific conditions in the following examples are usually measured according to national standards. If there is no corresponding national standard, then carry out according to general international standards, normal conditions or according to the conditions recommended by the manufacturer.

[0081] Example 1

[0082] A reverse flotation collector, the flotation desiliconization collector is N-butyl-2-sulfonic acid-1,3-propylenediamine.

[0083] The preparation method of N-butyl-2-sulfonic acid-1,3-propylenediamine is specifically as follows: acrylonitrile is reacted with ammonia to prepare 3-aminopropionitrile, and then catalytic hydrogenation is performed to obtain 1,3-propylenediamine; under alkaline conditions, 1,3-propylenediamine is subjected to a ring-opening reaction with butyl sultone to obtain an N-butylsulfonyl-protected 1,3-propylenediamine intermediate, and then the protecting group is removed by hydrolysis to obtain N-butyl-2-sulfonic acid-1,3-propylenediamine.

[0084] A method for desiliconization of bauxite by reverse flotation, comprising:

[0085] Adjusting the pH value of the bauxite slurry;

[0086] The inhibitor and the reverse flotation collector are sequentially added to the pH-adjusted bauxite slurry to perform reverse flotation desiliconization to obtain a desiliconized slurry.

[0087] Specifically, the raw bauxite ore with an Al2O3 content of 50.34% and an aluminum-silicon ratio of 4.37 was ground, the test water was tap water, the grinding fineness was 75.07% (<0.074mm), the reverse flotation temperature was 30°C, Na2CO3 was added to adjust the pH value of the slurry to 9.0, and then 100g / t of sodium hexametaphosphate inhibitor and 350g / t of reverse flotation desiliconization collector N-butyl-2-sulfonic acid-1,3-propylenediamine were added in sequence. Figure 3 The test flow of "one roughing, one cleaning and one scavenging" of the bauxite reverse flotation desiliconization method provided in the embodiment of the present application is tested.

[0088] Example 2

[0089] A reverse flotation collector is disclosed. The flotation desiliconization collector is N-decanesulfonic acid ethylenediamine and N-methylguanidinylpentanediamine, and the weight ratio of N-decanesulfonic acid ethylenediamine to N-methylguanidinylpentanediamine is 1:1.

[0090] The preparation method of N-decanesulfonic acid ethylenediamine comprises: firstly subjecting ethanolamine to a dehydrogenation reaction under the action of a catalyst to generate an aldehyde, and then subjecting ethanolamine to a dehydration reaction with ammonia to obtain ethylenediamine; and subjecting ethylenediamine to an aldehyde condensation reaction with 11-oxodecane-1-sulfonic acid to obtain N-decanesulfonic acid ethylenediamine.

[0091] The preparation method of N-methylguanidine pentamethylenediamine comprises: carrying out coupling reaction of appropriate amount of monopentylamine and catalyst (hydrochloric acid / sulfuric acid) to obtain pentamethylenediamine; mixing pentamethylenediamine with guanidinating agent (such as methylguanidine), adding catalyst, and carrying out chemical reaction, and purifying after reaction to obtain N-methylguanidine pentamethylenediamine.

[0092] A method for reverse flotation desiliconization of bauxite, comprising:

[0093] Adjusting the pH value of the bauxite slurry;

[0094] The inhibitor and the reverse flotation collector are sequentially added to the pH-adjusted bauxite slurry to perform reverse flotation desiliconization to obtain a desiliconized slurry.

[0095] Specifically, the raw bauxite ore with an Al2O3 content of 31.57% and an aluminum-silicon ratio of 3.26 was ground, the test water was tap water, the grinding fineness was 62.13% (<0.074mm), the reverse flotation temperature was 15°C, hydrochloric acid was added to adjust the pH value of the slurry to 9.0, and the inhibitor cationic polyacrylamide 85g / t, reverse flotation desiliconization collectors N-decanesulfonic acid ethylenediamine and N-methylguanidine pentamethylenediamine (1:1) were added in sequence, with a total amount of 800g / t, and the reaction temperature was 15°C. Figure 4 The test flow of "one roughing, two cleanings and one scavenging" of the bauxite reverse flotation desiliconization method provided in the embodiment of the present application is tested.

[0096] Example 3

[0097] A reverse flotation collector, wherein the flotation desiliconization collector is N-hexyl-3-guanidino-1,5-pentanediamine.

[0098] The preparation method of N-hexyl-3-guanidino-1,5-pentanediamine comprises: subjecting 1-aminopentane and 1-chlorohexane hexylating agent (such as hexyl halide) to alkylation reaction under alkaline conditions to obtain N-hexyl monoamine; converting N-hexyl monoamine to obtain N-hexyl-1,5-pentanediamine through coupling reaction; reacting N-hexyl-1,5-pentanediamine with cyanamide to form an intermediate containing guanidine group, and then subjecting the intermediate containing guanidine group to necessary modification, such as adjusting the substitution position, etc., to obtain N-hexyl-3-guanidino-1,5-pentanediamine.

[0099] A method for reverse flotation desiliconization of bauxite, comprising:

[0100] Adjusting the pH value of the bauxite slurry;

[0101] The inhibitor and the reverse flotation collector are sequentially added to the pH-adjusted bauxite slurry to perform reverse flotation desiliconization to obtain a desiliconized slurry.

[0102] Specifically, the raw bauxite ore with an Al2O3 content of 44.59% and an aluminum-silicon ratio of 4.58 was ground, the test water was tap water, the grinding fineness was 95.83% (<0.074mm), the reverse flotation temperature was 50°C, hydrochloric acid was added to adjust the pH value of the slurry to 4, dextrin inhibitor 65g / t and reverse flotation desiliconization collector N-hexyl-3-guanidino-1,5-pentanediamine 500g / t were added in sequence, and the reaction mixture was stirred for 24 hours. Figure 4 The test flow of "one roughing, two cleanings and one scavenging" of the bauxite reverse flotation desiliconization method provided in the embodiment of the present application is tested.

[0103] Example 4

[0104] A reverse flotation collector is disclosed. The flotation desiliconization collector is N-hexyl-3-guanidine-1,5-pentanediamine and N-(2-sulfonic acid group)propyl propylene diamine, and the weight ratio of N-hexyl-3-guanidine-1,5-pentanediamine to N-(2-sulfonic acid group)propyl propylene diamine is 2:1.

[0105] The preparation method of N-(2-sulfonic acid)propyl propylene diamine comprises: subjecting N-methyl propylamine to a reduction amination reaction with formaldehyde or acetone to obtain N,N-dimethyl-1,3-propylene diamine; subjecting N,N-dimethyl-1,3-propylene diamine to a sulfonation reaction with a sulfonating agent (concentrated sulfuric acid or chlorosulfonic acid) to introduce a sulfonic acid group into a specific position to obtain N-(2-sulfonic acid)propyl propylene diamine.

[0106] A method for desiliconization of bauxite by reverse flotation, comprising:

[0107] Adjusting the pH value of the bauxite slurry;

[0108] The inhibitor and the reverse flotation collector are sequentially added to the pH-adjusted bauxite slurry to perform reverse flotation desiliconization to obtain a desiliconized slurry.

[0109] Specifically, the raw bauxite ore with an Al2O3 content of 37.92% and an aluminum-silicon ratio of 3.47 was ground. The test water was tap water, the grinding fineness was 82.76% (<0.074mm), the reverse flotation temperature was 45°C, NaOH was added to adjust the pH value of the slurry to 7.5, and inhibitors such as sodium hexametaphosphate and starch (mass ratio 1:1) were added in sequence. 20g / t and reverse flotation desiliconization collectors N-hexyl-3-guanidino-1,5-pentanediamine and N-(2-sulfonic acid)propylpropylenediamine (2:1) were added in a total amount of 300g / t. Figure 3 The test flow of "one roughing, one cleaning and one scavenging" of the bauxite reverse flotation desiliconization method provided in the embodiment of the present application is tested.

[0110] Example 5

[0111] A reverse flotation collector, wherein the flotation desiliconization collector is N-ethylguanidino-2-sulfonic acid propylene diamine.

[0112] The preparation method of N-ethylguanidino-2-sulfonic acid propylene diamine comprises: carrying out a reduction amination reaction of ethylamine and acrolein in the presence of a catalyst to obtain N-ethyl-1,3-propylene diamine; carrying out a sulfonation reaction of N-ethyl-1,3-propylene diamine and a sulfonating agent chlorosulfonic acid to obtain N-ethyl-2-sulfonic acid propylene diamine; carrying out a chemical reaction of sulfonic acid diamine and cyanamide to introduce a guanidine group at a specific position, and purifying after the reaction to obtain N-ethylguanidino-2-sulfonic acid propylene diamine.

[0113] A method for desiliconization of bauxite by reverse flotation, comprising:

[0114] Adjusting the pH value of the bauxite slurry;

[0115] A depressant and a reverse flotation collector are sequentially added to the bauxite slurry after pH adjustment to perform reverse flotation desiliconization to obtain a desiliconized slurry.

[0116] Specifically, the raw bauxite ore with an Al2O3 content of 53.35% and an aluminum-silicon ratio of 4.61 was ground, the test water was tap water, the grinding fineness was 86.49% (<0.074mm), the reverse flotation temperature was 20°C, NaCO3 and NaOH (weight ratio 1:1) were added to adjust the slurry pH value to 10, and 50g / t of inhibitor starch and 650g / t of reverse flotation desiliconization collector N-ethylguanidino-2-sulfonic acid propylene diamine were added in sequence. Figure 3 The test flow of "one roughing, one cleaning and one scavenging" of the bauxite reverse flotation desiliconization method provided in the embodiment of the present application is tested.

[0117] Comparative Example 1

[0118] A method for desiliconization of bauxite by reverse flotation, comprising:

[0119] A bauxite ore with an Al2O3 content of 53.35% and an aluminum-silicon ratio of 4.61 was used, and the test water was deionized water. The preparation method of a bauxite reverse flotation collector in Chinese invention patent application CN102407189B was used for reverse flotation desiliconization. The aluminum-silicon ratio of the obtained flotation concentrate was 7.21, the aluminum oxide recovery rate was 80.54%, and the aluminum-silicon ratio of the tailings was 1.48.

[0120] Comparative Example 2

[0121] A method for desiliconization of bauxite by reverse flotation, comprising:

[0122] The raw bauxite ore with Al2O3 content of 53.35% and aluminum-silicon ratio of 4.61 was deionized water, and reverse flotation desiliconization was performed using a reverse flotation collector and flotation method provided by a triquaternary ammonium salt compound for mineral flotation as disclosed in Chinese invention patent application CN107350084B. The aluminum-silicon ratio of the obtained flotation concentrate was 6.89, the aluminum oxide recovery rate was 76.38%, and the aluminum-silicon ratio of the tailings was 1.54.

[0123] The test results of a method for reverse flotation desiliconization of bauxite provided in Examples 1 to 5 and Comparative Examples 1 to 2 are shown in Table 1 below.

[0124] Table 1 Test results of the method for desiliconization of bauxite by reverse flotation

[0125]

[0126] It can be seen from Table 1 that the collector and reverse flotation method provided in the embodiment of the present application can achieve the indicators of concentrate alumina recovery rate ≥ 85% and tailings aluminum-silicon ratio ≤ 1.30. By comparing the data of Comparative Examples 1 and 2 with Example 5, it can be seen that the collector provided in the present application can achieve better flotation effect under lower dosage conditions, and the collector has strong hard water adaptability.

[0127] One or more technical solutions in the embodiments of the present application also have at least the following technical effects or advantages:

[0128] (1) The reverse flotation collector provided in the embodiment of the present application is obtained by introducing -NH into a monoamine compound, and then introducing -CN3H4 and -SO3H functional groups on this basis to obtain a guanidine (sulfonic acid) diamine novel reverse flotation collector;

[0129] (2) The introduction of diamine groups and -CN3H4 in the reverse flotation collector provided in the embodiments of the present application enhances the interaction with hydroxyl, silicon, oxygen and other groups on the surface of the aluminosilicate mineral, thereby improving the selectivity of the reverse flotation collector. The introduction of -SO3H reduces the interaction with metal ions in hard water, improves the hard water resistance, and improves the adaptability of the collector in hard water. At the same time, the hydrocarbon non-polar macromolecular chains in R1 and / or R2 enhance the hydrophobicity of the surface of the mineral particles after the collector acts, thereby improving the collection capacity of the reverse flotation collector.

[0130] (3) Compared with conventional monoamine (such as fatty amine, alkylamine) and pyridine reverse flotation collectors, the reverse flotation collector provided in the embodiments of the present application has the advantages of high selectivity, low collector dosage and strong adaptability;

[0131] (4) The reverse flotation collector provided in the embodiment of the present application is combined with the optimized reverse flotation desiliconization method to achieve an aluminum concentrate product alumina recovery rate of ≥85% and a tailings aluminum-silicon ratio of ≤1.3.

[0132] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features applied for herein.

Claims

1. A reverse flotation collector having a chemical structure as shown in formula (I): R1-NH-R2-NH2 Formula (I) In formula (I), R1 and / or R2 include at least one of the following functional groups: -CN3H4 functional group, -SO3H functional group.

2. The reverse flotation collector according to claim 1, characterized in that: The carbon number of R1 is 2 to 10; and / or; The carbon number of R2 is 2-5.

3. The reverse flotation collector according to claim 1 or 2, characterized in that: The reverse flotation collector includes at least one of the following: N-decanesulfonic acid ethylenediamine, N-methylguanidine pentamethylenediamine, N-butyl-2-sulfonic acid-1,3-propylenediamine, N-hexyl-3-guanidine-1,5-pentanediamine, N-(2-sulfonic acid)propylpropylenediamine, and N-ethylguanidine-2-sulfonic acid propylenediamine.

4. A method for preparing a reverse flotation collector according to any one of claims 1 to 3, the method comprising: Obtain diamine organic matter; A -CN3H4 functional group and / or a -SO3H functional group are introduced into the diamine organic matter to obtain a reverse flotation collector.

5. The method according to claim 4, characterized in that The diamine organic matter includes at least one of the following: ethylenediamine, pentamethylenediamine, and propylenediamine.

6. The method according to claim 4 or 5, characterized in that: The method for obtaining the diamine organic compound comprises: The -NH2 functional group is introduced into the monoamine organic compound to obtain the diamine organic compound.

7. The method according to claim 6, characterized in that The monoamine organic substance includes at least one of the following: ethanolamine, dimethylamine, n-propylamine, isopropylamine, n-pentylamine, and isopentylamine.

8. A method for desiliconization of bauxite by reverse flotation, the method comprising: Adjusting the pH value of the bauxite slurry; The inhibitor and the reverse flotation collector according to any one of claims 1 to 3 are sequentially added to the bauxite slurry after pH adjustment to perform reverse flotation desiliconization to obtain a desiliconized slurry.

9. The method according to claim 8, characterized in that The weight of particles with a particle size of less than 0.074 mm in the bauxite slurry is ≥ 75.0%.

10. The method according to claim 8 or 9, characterized in that: The end point pH of the pH adjustment is 4 to 10; and / or, The inhibitor is added in an amount of 20 g / t dry ore to 100 g / t dry ore; and / or, The reverse flotation desiliconization temperature is 15°C to 50°C; and / or, The added amount of the reverse flotation collector is 300.0 g / t to 800.0 g / t of ore pulp.

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