A flotation reagent and a method for the flotation separation of fine-grained cassiterite from magnesium-containing gangue minerals

Abstract

The application discloses a kind of floatation reagent and the method for microfine tin stone and magnesium-containing gangue mineral floatation separation, belong to mineral processing technical field.The floatation reagent includes collector and inhibitor;Collector is phosphonic acid nanocolloid collector, and phosphonic acid nanocolloid collector is assembled by phosphonic acid compound and divalent metal ion coordination;Inhibitor is hydroxyl polysaccharide compound;The collector can promote the targeted aggregation of microfine tin stone, realize the effective collection of microfine tin stone, the inhibitor can selectively occur hydroxyl activation and isosite adsorption on the magnesium site on the surface of magnesium-containing gangue, realize the hydrophilic activation and flocculation activation of magnesium-containing gangue mineral, realize the selective inhibition of magnesium-containing gangue mineral, so as to be under the joint action of both, strengthen the efficient floatation separation of microfine tin stone and magnesium-containing gangue mineral.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of floatation reagent, in particular to a kind of floatation reagent for micro fine tin stone and magnesium gangue mineral separation, further relates to a kind of micro fine tin stone and magnesium gangue mineral floatation separation reagent and method, belongs to mineral floatation technical field. BACKGROUND

[0002] Tin stone (SnO2) is the most important raw material for extracting tin metal in industry, and the tin metal extracted from tin stone is widely used in soldering, photoelectric, catalysis, tin chemical products and tin-plated sheet, etc. fields, and is one of the important resources for scientific and technological development. However, most of the tin resources exist in primary ore deposits. Such tin resources are mainly formed in the process of magmatic hydrothermal evolution. When the tin-containing hydrothermal fluid meets magnesium-iron-containing minerals such as biotite, it can be replaced to form magnesium-rich chlorite and other minerals, or it can be in contact with carbonatite country rock to form magnesium-rich tourmaline and other gangue minerals in the hydrothermal and country rock contact zone. The tin resources formed in this way have the disadvantages of fine dissemination size and complex associated components, and must be subjected to crushing and grinding operation before mineral separation. Tin stone is brittle and easy to be slimed, and the crushing and grinding operation will inevitably cause the sliming of part of the tin stone, making it difficult to recover and resulting in the loss of tin resources. In addition, magnesium-rich tourmaline and magnesium-rich chlorite and other magnesium-containing clay gangue minerals also have the characteristics of easy sliming, which further hinders the recovery of micro fine tin stone.

[0003] At present, with the aggravation of the shortage of tin resources, attempts have been made in industry to recover micro fine tin-containing resources. The commonly used tin stone collector at present is hydroxamic acid collector. Such reagent has good collecting property and selectivity in collecting conventional particle size tin stone, but its collecting property and selectivity are obviously insufficient in the process of micro fine tin stone flotation. Therefore, the development of a collector suitable for micro fine tin stone is one of the key points for the recovery of micro fine tin resources. In addition, the flotation separation of magnesium-containing gangue minerals and micro fine tin stone is also one of the research focuses. At present, common inhibitors such as water glass, sodium fluosilicate and nano alkaline earth metal fluoride colloidal particles (CN109985731B) can achieve the inhibition of magnesium-containing gangue minerals to some extent by enhancing the hydrophilicity of magnesium-containing gangue minerals. However, such inhibitors cannot effectively prevent the micro fine magnesium-containing gangue minerals suspended in the ore pulp from entering the concentrate product with the fluid and foam layer, and it is difficult to achieve the effective enrichment and recovery of micro fine tin stone. Therefore, the further development of reagents and methods for the flotation separation of micro fine tin stone and magnesium-containing gangue minerals to achieve the efficient flotation enrichment of micro fine tin stone and the efficient inhibition of magnesium-containing gangue minerals is of great significance for the development and utilization of micro fine tin-containing resources. SUMMARY

[0004] In view of the technical problems existing in the existing fine-grained cassiterite and magnesium-containing gangue minerals and the flotation separation process, a first object of the present application is to provide a flotation reagent for separating fine-grained cassiterite from magnesium-containing gangue minerals, wherein the collector can realize the targeted aggregation of fine-grained cassiterite, increase the size of fine-grained cassiterite, and has the advantages of strong collecting property, and the inhibitor used in combination can selectively cause hydroxyl activation and isotope adsorption on the magnesium sites on the surface of magnesium-containing gangue, realize the hydrophilic activation and flocculation activation of magnesium-containing gangue minerals, and thus the combination of the two can realize the selective inhibition of magnesium-containing gangue minerals.

[0005] In order to achieve the above technical purpose, the present application provides a flotation reagent for separating fine-grained cassiterite from magnesium-containing gangue minerals, which comprises a collector and an inhibitor; the collector is a phosphonic acid nanocolloid collector; the phosphonic acid nanocolloid collector is assembled by coordination of a phosphonic acid compound and a divalent or higher metal ion; the phosphonic acid compound contains at least one C6-C 18 long-chain alkyl group and at least one phosphonic acid group; and the inhibitor is a hydroxyl polysaccharide compound.

[0006] The flotation reagent provided by the present application contains a phosphonic acid nanocolloid collector and a hydroxyl polysaccharide inhibitor, the phosphonic acid nanocolloid collector has a targeted aggregation effect on fine-grained cassiterite, and the hydroxyl polysaccharide compound has a hydrophilic activation and flocculation activation effect on magnesium-containing gangue minerals, the combination of the two can strengthen the flotation separation of fine-grained cassiterite from magnesium-containing gangue minerals, and achieve a good separation effect. The phosphonic acid nanocolloid collector is assembled by chelation between a phosphonic acid compound and a high-valence metal ion to form a phosphonic acid nanocolloid, the obtained phosphonic acid nanocolloid has multiple active sites, which can realize the targeted attraction between the phosphonic acid nanocolloids and between the phosphonic acid nanocolloids and fine-grained cassiterite, thereby promoting the targeted aggregation of fine-grained cassiterite, realizing the efficient collection and recovery of fine-grained cassiterite, and the hydroxyl and carboxyl groups contained in the hydroxyl polysaccharide compound can cause hydroxyl activation and isotope adsorption on the abundant magnesium sites on the surface of magnesium-containing gangue minerals, realize the hydrophilic activation and flocculation activation of magnesium-containing gangue minerals, increase the particle size and hydrophilic activity of magnesium-containing gangue minerals, and reduce the floatability of magnesium-containing gangue minerals, thereby realizing the inhibition of magnesium-containing gangue minerals.

[0007] The C6-C 18 long-chain alkyl group in the phosphonic acid compound can be a straight-chain alkyl group or a branched-chain alkyl group.

[0008] As a preferred scheme, the phosphonic acid compound comprises at least one of hexyl phosphonic acid, heptyl phosphonic acid, octyl phosphonic acid, dodecyl amine-based bis-methylene phosphonic acid, dioctyl phosphonic acid, 2-butyl octyl phosphonic acid, and alpha-hydroxy hexyl phosphonic acid.

[0009] The phosphonic acid nanocolloid collector of the present application is assembled by coordination of phosphonic acid compound and divalent or higher metal ions, and there are multiple coordination assembly modes of the phosphonic acid compound and divalent or higher metal ions simultaneously, and the phosphonic acid nanocolloid collector can be a mixture of multiple coordination assemblies or a single coordination assembly, and the coordination assembly of divalent metal ions and long-chain alkyl phosphonic acid is taken as an example for illustration, and the typical coordination assembly structure formula is as follows: and the like; wherein, M is divalent or higher metal ions; R is C6-C 18 alkyl chain.

[0010] As a preferred scheme, the divalent or higher metal ions are at least one of Pb 2+ , Zn 2+ , Cu 2+ , Fe 3+ Different central metal ions have different effects on the tin stone.

[0011] As a preferred scheme, the coordination mass ratio of the phosphonic acid compound and divalent or higher metal ions is 0.5:1-2:1.

[0012] The phosphonic acid nanocolloid collector of the present application is assembled by coordination chelation of phosphonic acid compound and divalent or higher metal ions to form a complex with certain spatial structure, and these complexes have nanocolloid properties, large specific surface area, and a large number of active sites on the surface, and can realize target attraction between the phosphonic acid nanocolloid itself and between the phosphonic acid nanocolloid and the micro-fine tin stone, promote the target aggregation of the micro-fine tin stone, and thus realize high-efficiency collection of the micro-fine tin stone.

[0013] As a preferred scheme, the hydroxyl polysaccharide compound is at least one of carboxymethyl cellulose, sodium carboxymethyl cellulose, and guar gum. The preferred hydroxyl polysaccharide compound has hydroxyl activation and isosite adsorption on the magnesium sites on the surface of tourmaline and chlorite minerals, can realize hydrophilic activation and flocculation activation of the surfaces of these minerals, increase the particle size and hydrophilic activity of these minerals, and thus inhibit the floatability thereof.

[0014] The present application also provides a method for flotation separation of micro-fine tin stone and magnesium-containing gangue minerals, which comprises the following steps: sequentially performing magnetic separation for removing iron and flotation for removing sulfur on low-grade micro-fine tin ore containing magnesium-containing gangue minerals, and then performing flotation separation by using the flotation reagent to obtain micro-fine tin concentrate.

[0015] As a preferred scheme, the magnesium-containing gangue mineral is at least one of tourmaline and chlorite.

[0016] As a preferred scheme, the flotation separation comprises one roughing and 3-5 times of cleaning.

[0017] As a preferred scheme, the flotation reagent system in the roughing process is as follows: collector 500-1000 g / t; depressant 40-200 g / t. The collector is added in the form of a solution with a mass concentration of 2.5-5%. The depressant is added in the form of a solution with a mass concentration of 0.2-0.5%. Sodium carbonate is also used as a pH adjuster in the roughing process, and the amount of sodium carbonate used ranges from 500 to 1000 g / t.

[0018] As a preferred scheme, the flotation reagent system in the roughing process is as follows: collector 500-1000 g / t; depressant 40-200 g / t. The collector is added in the form of a solution with a mass concentration of 2.5-5%. The depressant is added in the form of a solution with a mass concentration of 0.2-0.5%. Sodium carbonate is also used as a pH adjuster in the roughing process, and the amount of sodium carbonate used ranges from 500 to 1000 g / t.

[0019] Under the preferred flotation process and reagent system, the final flotation froth concentrate product is a cassiterite concentrate with a tin grade of 5.55-10.24% and a tin recovery rate of 31.65%-45.37%.

[0020] The specific steps of the method for floating and separating micro-fine cassiterite from magnesium-containing gangue minerals are as follows:

[0021] (1) Iron removal: The low-grade micro-fine tin-containing raw ore is first subjected to magnetic separation for iron removal, with a magnetic field strength of 1-1.2 T. The non-magnetic product obtained is subjected to concentration treatment, and the concentration of the concentrated ore slurry is 40-50%, to obtain the flotation raw ore.

[0022] (2) Desulfurization: The flotation raw ore obtained in step (1) is subjected to reverse flotation desulfurization treatment to remove sulfide minerals from the flotation raw ore, to obtain froth tailings and tank desulfurization concentrate. The desulfurization process is a conventional operation in the prior art.

[0023] (3) Tin flotation: Sodium carbonate as a pH adjuster is added to the desulfurization concentrate obtained in step (2) and stirred for 3-4 min. A hydroxyl polysaccharide compound as a depressant is added and stirred for 3-4 min. A phosphonic acid nanocolloid collector is added and stirred for 4-6 min. A frother is added and stirred for 0.5-1 min. The flotation time is 4-6 min, to obtain a flotation froth concentrate. The pH adjuster, sodium carbonate, is added in the form of a sodium carbonate solution with a mass percentage concentration of 1-10%, and the pure dry weight is 500-1000 g / (t·flotation raw ore). The depressant, hydroxyl polysaccharide compound, is added in the form of a hydroxyl polysaccharide solution with a mass percentage concentration of 0.2-0.5%, and the pure dry weight of the hydroxyl polysaccharide compound is 40-200 g / (t·flotation raw ore). The phosphonic acid nanocolloid collector is added in the form of a nanocolloid solution with a mass concentration of 2.5-5%, and the pure dry weight of the phosphonic acid nanocolloid collector is 500-1000 g / (t·flotation raw ore). The pH adjuster is sodium carbonate with a mass concentration of 5-10%, and the ratio of the amount of sodium carbonate to the amount of collector ranges from 0.8:1 to 1.2:1. The rotation speed of the flotation machine is 1900-2100 r / min.

[0024] (4) Concentration: the flotation froth concentrate obtained in step (3) is taken as the raw ore for concentration, and 3-5 concentration operations are performed, each of which adds the inhibitor hydroxyl polysaccharide compound and performs pulp conditioning for 3 min, and the flotation time is 1-4 min, to obtain the final flotation froth concentrate. The hydroxyl polysaccharide compound is added in the form of a hydroxyl polysaccharide compound solution with a mass percentage concentration of 0.2-0.5%, and the pure dry weight of the hydroxyl polysaccharide compound is 0.1-50 g / (t· raw ore for flotation).

[0025] (5) Flotation product treatment: the final flotation froth concentrate product is filtered and dried to obtain a tin ore concentrate with a tin grade of 5.55-10.24% and a tin recovery rate of 31.65%-45.37%.

[0026] Compared with the prior art, the technical scheme of the present application has the following beneficial technical effects:

[0027] The flotation reagent for separating micro-fine tin ore from magnesium-containing gangue minerals provided by the present application comprises a novel phosphonic acid nanocolloid collector formed by coordination assembly of a phosphonic acid compound and a divalent or higher metal ion, can realize targeted aggregation of micro-fine tin ore and increase the size of the micro-fine tin ore, has the advantage of strong collecting property, can realize efficient collection of micro-fine tin ore, and contains a hydroxyl polysaccharide compound inhibitor, which can selectively cause hydroxyl activation and site adsorption on magnesium sites on the surface of magnesium-containing gangue, realize hydrophilic activation and flocculation activation of the magnesium-containing gangue minerals, realize selective inhibition of the magnesium-containing gangue minerals, and through the combined use of the phosphonic acid nanocolloid collector and the hydroxyl polysaccharide compound inhibitor, the flotation separation effect between the micro-fine tin ore and the magnesium-containing gangue can be strengthened, and finally a tin ore concentrate with a tin grade of 5.55-10.24% and a tin recovery rate of 31.65%-45.37% can be obtained. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a flotation process flowchart of Example 2 and Example 3.

[0029] Figure 2 It is a single mineral liberation diagram of tin ore in the micro-fine tin-containing raw ore of Example 2.

[0030] Figure 3 It is an infrared spectrum diagram of the preparation of the phosphonic acid nanocolloid collector in Example 1 (taking dodecylamine-based bis-methylene phosphonic acid and lead ions as an example for coordination); Figure 3 cm-1; 3199.91 cm-1 -1 cm-1; 2956.88 cm-1 -1 cm-1; 2922.16 cm-1 -1 cm-1; 2852.72 cm-1-1 peaks near 1454.33 cm -1 -1 peaks near 866.04 cm -1 peaks near 1120.64 cm -1 peaks near 1045.42 cm -1 peaks near 690.52 cm -1 peaks near 470.63 cm -1 peaks near 400.00 cm DETAILED DESCRIPTION

[0031] The present application will be further described with reference to the drawings and examples, but the scope of the present application is not limited to the following content.

[0032] Example 1

[0033] The synthesis method of phosphonic acid nanocolloid collector is as follows:

[0034] For example, the synthesis of phosphonic acid nanocolloid collector with dodecylamine dimethyl phosphonic acid and lead ions: dodecylamine dimethyl phosphonic acid is placed in a 5% sodium hydroxide solution to prepare a 1% dodecylamine dimethyl phosphonic acid solution, and a 0.07 mol / L lead nitrate solution is prepared with ultrapure water. 20g of dodecylamine dimethyl phosphonic acid solution is placed in a beaker, and the beaker is placed in a constant temperature water bath with an ultrasonic generator. The magnetic stirring system and ultrasonic generator are turned on and heated to 80°C. The lead ion solution is slowly added to the phosphonic acid solution under magnetic stirring at a rate of 0.01 mL / s. The mass ratio of lead nitrate to diphosphonic acid is 1:1. After the addition is completed, the temperature is kept constant for 1 hour to obtain the phosphonic acid nanocolloid collector solution. Finally, the collector solution is placed in a vacuum oven at 45°C and dried for about 48 hours to obtain solid phosphonic acid nanocolloid collector.

[0035] Example 2

[0036] The tin grade of a certain low-grade fine-grained tin-containing tailings in a certain place is about 0.16%, and the main gangue minerals are magnesio-elbaite and the like, as shown in Table 1, wherein the content of magnesio-elbaite is about 50%. The phosphonic acid nanocolloid collector synthesized in Example 1 is used as the collector for cassiterite, and carboxymethyl cellulose sodium is used as the depressant for the magnesium-containing gangue mineral magnesio-elbaite. Among them, carboxymethyl cellulose sodium and sodium carbonate are analytically pure, and phosphonic acid nanocolloid collector is industrial pure. The application is carried out according to the following steps: Figure 2

[0037] ​​(1) Iron removal: A high gradient magnetic separator is used to remove iron from the fine particle tin-containing tailings, and the magnetic field strength is selected to be 1.2T. The non-magnetic product is obtained and the concentrate of the slurry is 45% as the raw ore for flotation;

[0038] (2) Desulfurization: The raw ore for flotation in step (1) is added to a hanging tank flotation machine, and the desulfurization operation includes one roughing, one cleaning and one scavenging. The sulfide activator is copper sulfate, and the sulfide collector is xanthate. The dosage of copper sulfate for roughing is 100 g / (t raw ore for flotation), and the dosage of xanthate for roughing is 200 g / (t raw ore for flotation). No reagent is added for cleaning, and the dosage of xanthate for scavenging is 100 g / (t raw ore for flotation). The froth tailings and the tank desulfurization concentrate are obtained.

[0039] (3) Tin flotation: 1000 g / (t raw ore for flotation) of 5% mass percentage sodium carbonate solution is added to the tank desulfurization concentrate slurry obtained in step (2) and stirred for 3 min. 50 g / (t raw ore for flotation) of 0.5% mass percentage sodium carboxymethyl cellulose is added and stirred for 3 min. 1000 g / (t raw ore for flotation) of phosphonic acid nanocolloid collector is added and stirred for 5 min. The frother is added and stirred for 1 min. The positive flotation is scraped, and the froth concentrate product and the tank tailings product are obtained.

[0040] (4) Cleaning: The froth concentrate product in step (3) is subjected to 5 cleaning operations. Sodium carboxymethyl cellulose (added in the form of a 0.5% mass percentage solution) is used as an inhibitor and stirred for 3 min in each cleaning operation. The dosages of sodium carboxymethyl cellulose in the first to fifth cleanings are 10 g / (t raw ore for flotation), 2 g / (t raw ore for flotation), 1 g / (t raw ore for flotation), 0.5 g / (t raw ore for flotation), and 0.1 g / (t raw ore for flotation), respectively. The final froth product is obtained.

[0041] (5) Flotation product treatment: The tailings product obtained in step (3) and the final froth product in step (4) are filtered, dried, weighed, assayed, and the product indexes are calculated. The final tin concentrate has a tin grade of 10.24% and a tin recovery rate of 34.05%.

[0042] Example 3

[0043] The tin grade of the fine particle tin-containing resources in a certain area used in the example is about 0.23%, and the main gangue mineral is chlorite, etc., among which the chlorite content is about 40%, with high mud degree and large inhibition difficulty. The process of example 1 is used to synthesize heptyl phosphonic acid + Pb 2+ / Cu 2+ , dioctyl phosphonic acid + Pb 2+ / Zn 2+ , alpha-hydroxy hexyl phosphonic acid + Pb 2+ / Fe 3+ Phosphonic acid nanocolloid collector as an example of flotation collector, hydroxyl polysaccharide compound guar gum as an inhibitor of chlorite. Among them, guar gum, pH regulator sodium carbonate are analytical pure, cassiterite collector is industrial pure, and the application is carried out according to the following steps:

[0044] (1) Iron removal: using a vertical ring high gradient magnetic separator to remove iron from fine particle tin-containing tailings, removing magnetic iron-containing impurities, and selecting a magnetic field strength of 1.2T to obtain a non-magnetic product and concentrate the slurry concentration to 45% as the flotation feed;

[0045] (2) Desulfurization: adding the flotation feed of step (1) to a hanging tank flotation machine, and the desulfurization operation includes one roughing, one cleaning and one scavenging. The sulfide ore activator is copper sulfate, and the sulfide ore collector is xanthate. The dosage of copper sulfate for roughing is 200g / (t·flotation feed), the dosage of xanthate for roughing is 200g / (t·flotation feed), no reagent is added for cleaning, and the dosage of xanthate for scavenging is 100g / (t·flotation feed). The foam tailings and tank desulfurization concentrate are obtained.

[0046] (3) Tin flotation: adding 750g / (t·flotation feed) of 5% mass percentage sodium carbonate solution to the tank desulfurization concentrate slurry obtained in step (2) and conditioning for 3min, adding 150g / (t·flotation feed) of 0.5% mass percentage guar gum and conditioning for 3min, adding 1000g / (t·flotation feed) of different phosphonic acid nanocolloid collectors and conditioning for 5min, adding a foaming agent and conditioning for 1min, and performing positive flotation scraping to obtain foam concentrate product and tank tailings product;

[0047] (4) Cleaning: The foam concentrate product of step (3) is subjected to 4 cleaning operations, and guar gum (added in the form of a 0.5% mass percentage solution) is used as an inhibitor and conditioned for 3min in each cleaning operation. The dosage of guar gum in the first to fourth cleaning operations is 40g / (t·flotation feed), 30g / (t·flotation feed), 15g / (t·flotation feed), and 10g / (t·flotation feed), respectively, to obtain the final foam product;

[0048] (5) Flotation product treatment: filtering, drying, weighing, assaying the grade and calculating the product index of the tailings product obtained in step (3) and the final foam product of step (4). The flotation index of the final tin concentrate is shown in Table 1.

[0049] Table 1 Flotation concentrate index of phosphonic acid nanocolloid collector

[0050]

[0051] Comparative Example 1

[0052] The raw ore for flotation in this example is the non-magnetic product after iron removal in Example 2, with a tin grade of about 0.21%. The effects of other conventional inhibitors on the inhibition of dravite and hydroxyl polysaccharide carboxymethyl cellulose are compared. Sodium fluosilicate, carboxymethyl cellulose, and pH adjuster sodium carbonate are all analytical pure, colloidal phosphonic acid collector (synthesized in Example 1) and water glass are all industrial pure. The application is carried out according to the following steps:

[0053] (1) Desulfurization: The raw ore for flotation is added to a hanging tank flotation machine, and then a desulfurization roughing operation is carried out. Copper sulfate and xanthate are used as the activator and collector of sulfide ore, respectively. The dosage of copper sulfate is 100 g / (t raw ore for flotation), and the dosage of xanthate is 200 g / (t raw ore for flotation). The froth tailings and tank desulfurization concentrate are obtained.

[0054] (2) Tin flotation: 1000 g / (t raw ore for flotation) of 5% mass percentage sodium carbonate solution is added to the tank desulfurization concentrate slurry obtained in step (1) and stirred for 3 min. Different types and dosages of inhibitors are added and stirred for 3 min. 1000 g / (t raw ore for flotation) of colloidal phosphonic acid collector is added and stirred for 5 min. A foaming agent is added and stirred for 1 min. The positive flotation is scraped and the froth concentrate product and tank tailings product are obtained.

[0055] (3) Concentration: The froth concentrate product of step (2) is subjected to a blank concentration operation, and the first concentrate product is obtained.

[0056] (4) Flotation product treatment: The tailings product obtained in step (2) and the final froth product of step (3) are filtered, dried, weighed, and analyzed for grade to calculate the product index. The first concentrate products obtained using different types and dosages of inhibitors are obtained.

[0057] Among them, the different types and dosages of inhibitors in step (2) include 50, 100, 200 g / (t raw ore for flotation) of sodium fluosilicate (pure dry weight), 200, 400, 600, 1000 g / (t raw ore for flotation) of water glass (original solution), and 50, 100 g / (t raw ore for flotation) of hydroxyl polysaccharide carboxymethyl cellulose. The final flotation index is shown in Table 2.

[0058] Other conventional inhibitors such as sodium fluosilicate and water glass cannot effectively inhibit dravite. Hydroxyl polysaccharide carboxymethyl cellulose can effectively inhibit dravite at a lower dosage and under one blank concentration condition. The tin grade is increased from 0.2% to 1.15-1.39%, and the tin recovery rate in the first concentrate remains at a high level, reaching 41.42-53.56%.

[0059] Table 2 Flotation results of primary concentrate under different inhibitor conditions

[0060]

[0061] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered within the scope of protection of the present application.

[0062] Comparative Example 2

[0063] The primary ore used in this example is the same as that used in Comparative Example 1, with a tin grade of about 0.21%. The difference in flotation of cassiterite between the phosphonic acid nanocolloid collector synthesized in Comparative Example 1 and the dodecyl amine dimethyl phosphonic acid collector. The example is carried out according to the following steps:

[0064] (1) Desulfurization: The primary ore is added to the hanging tank flotation machine, followed by a one-time desulfurization roughing operation, with copper sulfate and xanthate as the activator and collector of sulfide ore, respectively, with a copper sulfate dosage of 100 g / (t primary ore) and a xanthate dosage of 200 g / (t primary ore), to obtain froth tailings and tank desulfurization concentrate.

[0065] (2) Tin flotation: 1000 g / (t primary ore) of 5% sodium carbonate solution is added to the tank desulfurization concentrate slurry obtained in step (1) and stirred for 3 min, 50 g / (t primary ore) of sodium carboxymethyl cellulose is added as an inhibitor and stirred for 3 min, 1000 g / (t primary ore) of different collectors is added and stirred for 5 min, and a frother is added and stirred for 1 min, followed by positive flotation scraping, to obtain froth concentrate products and tank tailings products;

[0066] (3) Concentration: The froth concentrate product of step (2) is subjected to a one-time blank concentration operation to obtain primary concentrate products.

[0067] (4) Flotation product treatment: The tailings product obtained in step (2) and the final froth product of step (3) are filtered, dried, weighed, assayed, and the product indicators are calculated to obtain primary concentrate products using different types and amounts of inhibitors, and the final flotation indicators are shown in Table 3.

[0068] Compared with single dodecyl amine dimethyl phosphonic acid as a cassiterite flotation collector, the phosphonic acid nanocolloid collector synthesized in Example 1 exhibits superior collecting ability and selectivity for cassiterite, and is more easily to realize effective enrichment of low-grade fine-grained tin-containing minerals.

[0069] Table 3 Comparison of primary concentrate indicators of single phosphonic acid collector and phosphonic acid nanocolloid collector

[0070]

Claims

1. A flotation reagent for separating micro-fine cassiterite from magnesium-containing gangue minerals, characterized in that: the flotation reagent comprises a collector and an inhibitor; the collector is a phosphonic nanocolloid collector; the phosphonic nanocolloid collector is assembled by coordination of a phosphonic compound and metal ions with valence of two or more; the phosphonic compound comprises at least one of hexyl phosphonic acid, heptyl phosphonic acid, octyl phosphonic acid, dodecyl amine bis dimethyl phosphonic acid, dioctyl phosphonic acid, 2-butyloctyl phosphonic acid, and a-hydroxy hexyl phosphonic acid; and the inhibitor is a hydroxyl polysaccharide compound; the coordination mass ratio of the phosphonic compound to the metal ions with valence of two or more is 0.5: 1-2: 1; and the hydroxyl polysaccharide compound is at least one of carboxymethyl cellulose, sodium carboxymethyl cellulose, and guar gum. After low-grade micro-fine tin ore containing magnesium gangue minerals is sequentially subjected to magnetic separation for removing iron and flotation for removing sulfur, the micro-fine cassiterite concentrate is obtained by using the flotation reagent according to any one of claims 1-4 for flotation separation. The magnesium-containing gangue minerals are at least one of magnesium tourmaline and chlorite. The flotation separation comprises one roughing process and 3-5 cleaning processes. In the roughing process, the flotation reagent system is: collector 500-1000 g / t; and inhibitor 40-200 g / t. In the cleaning process, the flotation reagent system is: inhibitor 0.1-50 g / t.

2. A flotation reagent for separating fine-grained cassiterite from magnesium-containing gangue minerals according to claim 1, characterized in that: The divalent or more metal ion is at least one of Pb 2+ , Zn 2+ , Cu 2+ , Fe 3+ .

3. A flotation reagent for separating fine-grained cassiterite from magnesium-containing gangue minerals according to claim 1 or 2, characterized in that: ​ 4. A flotation reagent for separating fine grained cassiterite from magnesium containing gangue minerals according to claim 1, characterized in that: ​ 5. A process for the flotation separation of fine grained cassiterite from magnesium containing gangue minerals characterised in that: ​ 6. A process for the flotation separation of fine grained cassiterite from magnesium containing gangue minerals according to claim 5 characterised in that: ​ 7. A process for the flotation separation of fine grained cassiterite from magnesium containing gangue minerals according to claim 5 or 6 characterised in that: ​ 8. A process for the flotation separation of fine grained cassiterite from magnesium containing gangue minerals according to claim 7 characterised in that: ​ 9. A process for the flotation separation of fine grained cassiterite from magnesium containing gangue minerals according to claim 7 characterised in that: ​

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