Metal ore flotation collecting agent and preparation method thereof

Abstract

The invention belongs to the technical field of mineral flotation, and particularly relates to a metal ore flotation collecting agent and a preparation method thereof. The metal ore flotation collecting agent is designed and synthesized, and experimental results show that the collecting agent can effectively adapt to the characteristics of low-grade nickel-copper sulfide ore, and the collecting effect is remarkably improved.

Description

Technical Field

[0001] The invention belongs to the technical field of mineral flotation, and in particular relates to a metal ore flotation collector and a preparation method thereof. Background Art

[0002] Flotation collectors are specialized chemical agents whose core function is to alter the physical and chemical properties of a mineral's surface, or to adjust its floatability by creating specific conditions. By modifying the mineral's surface physical and chemical properties, such as electrical and wettability, these agents alter the mineral's floatability during flotation, thereby enabling mineral separation.

[0003] Low-grade copper-nickel ores contain valuable minerals such as pyroxenite and magnetite, as well as silicate gangue minerals. The industry's goal is to separate the sulfide copper-nickel ore from this type of ore. However, excessive magnesium oxide content in the concentrate can severely impact the flash furnaces used in pyrometallurgical smelting equipment. Because magnesium-containing silicate ores have a higher melting point than sulfide copper-nickel ore, the resulting slag has high viscosity, making slag phase separation difficult. This can lead to serious damage, such as furnace nodules and furnace wall corrosion.

[0004] Prior art CN103224472 discloses that cyanuric chloride is grafted with organic amine and then reacted with carbon disulfide to prepare a dithiocarbamate heavy metal scavenger with suitable molecular weight and high chelating ability. The heavy metal scavenger can chelate Hg in water. 2+ , Pb 2+ 、Cd 2+ Cr 3+ 、Ni 2+ 、Cu 2+ The heavy metal ions react rapidly to precipitate and separate, thereby separating and removing the heavy metals. However, the prior art does not disclose the application of cyanuric chloride compounds in the flotation enrichment process of copper-nickel ore.

[0005] Based on the above background technology, there is an urgent need to develop a metal ore flotation collector with high selectivity to overcome the problem that the existing collectors have a poor collection effect on low-grade nickel ores. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, the primary purpose of the present invention is to provide a metal ore flotation collector that can effectively adapt to the characteristics of low-grade nickel-copper sulfide ore and significantly improve the collection effect.

[0007] Another object of the present invention is to provide a method for preparing the above-mentioned metal ore flotation collector, which is simple and feasible.

[0008] The purpose of the present invention is achieved through the following technical solutions: A metal ore flotation collector, the structural formula of the metal ore flotation collector is: Wherein, n is 4, 5 or 6.

[0009] The preparation method of the metal ore flotation collector comprises the following steps: (1) Sodium hydroxide and ω-hydroxy fatty acid are added to water to obtain a mixed solution; the mixed solution is added to an acetone solution of cyanuric chloride at 0-5°C and reacted under stirring; after the reaction is completed, intermediate 1 is obtained through post-treatment; The structural formula of the intermediate 1 and ω-hydroxy fatty acid is: Wherein, n is 4, 5 or 6; (2) The intermediate 1 and 6-(methylthio)pyridin-3-amine are added to N,N-dimethylformamide, and N,N,N',N'-tetramethylchloroformamidine hexafluorophosphate and N-methylimidazole are added at 0-5°C, and then the temperature is raised to room temperature for reaction; n-heptane is added to the reaction system, filtered, and the filter residue is added to N,N-dimethylformamide, and sodium ethylsulfate is added, and the reaction is heated under stirring; after the reaction is completed, the metal ore flotation collector is obtained through post-treatment.

[0010] The invention uses cyanuric chloride and the hydroxyl group of ω-hydroxy fatty acid to undergo Mitsunobu reaction to prepare an intermediate 1, and introduces a carboxyl group with an ether bond; the carboxyl group of the intermediate 1 undergoes amide condensation with the amino group of 6-(methylthio)pyridin-3-amine, and introduces a thioether bond with a pyridine group and an amide group; and then the thioether bond is hydrolyzed under alkaline conditions to prepare a metal ore flotation collector containing a thiol group.

[0011] According to the above-mentioned preparation method of the metal ore flotation collector, further, in step (1), the molar ratio of sodium hydroxide, ω-hydroxy fatty acid and cyanuric chloride is (6.5-7): (3.2-3.5):1.

[0012] According to the above-mentioned method for preparing a metal ore flotation collector, further, the reaction time in step (1) is 3-5 h.

[0013] According to the above-mentioned preparation method of the metal ore flotation collector, further, in step (2), the molar ratio of the intermediate 1, 6-(methylthio)pyridin-3-amine, N,N,N',N'-tetramethylchloroformamidine hexafluorophosphate, N-methylimidazole and sodium ethylsulfate is 1:(4-5):(6-8):(10-12):(3.5-4).

[0014] According to the above-mentioned method for preparing a metal ore flotation collector, further, the reaction time at room temperature in step (2) is 12-16 h.

[0015] According to the above-mentioned method for preparing a metal ore flotation collector, further, the temperature of the heating reaction in step (2) is 110-130° C., and the time is 12-16 h.

[0016] According to the above-mentioned preparation method of the metal ore flotation collector, further, the post-treatment operation in step (1) is: pouring the reaction solution into a 1 mol / L hydrochloric acid solution, filtering, and slurrying the collected filter residue with hot water, filtering again and then drying.

[0017] The present invention has the following effects compared to the prior art: The present invention designs and synthesizes a metal ore flotation collector. Experimental results show that the collector can effectively adapt to the characteristics of low-grade nickel-copper sulfide ores and significantly improve the collection effect. Specifically, the sulfur atom of the thiol group in the metal collector of the present invention has a strong affinity and can undergo chemical adsorption with metal ions to form a strong metal-sulfur bond; the pyridine group has good electron donor properties and can form a coordination bond with metal ions; the melamine group has multiple nitrogen atoms and can form a multi-coordinated chelate with metal ions; the ether bond can increase the flexibility and polarity of the collector molecule, which helps the collector molecule to better adapt to the chemical environment of the mineral surface; and the introduced fatty chain can provide hydrophobicity and enhance the adsorption stability of the collector molecule on the mineral surface; the synergistic effect of these functional groups can significantly improve the collector's selective capture ability for metal minerals such as nickel and copper. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the synthesis of the metal ore flotation collector of the present invention; Figure 2 For the intermediate 1 of Example 1 of the present invention 1 H NMR spectrum; Figure 3 This is the HRMS spectrum of intermediate 1 of Example 1 of the present invention; Figure 4 The metal ore collector of Example 1 of the present invention 1 H NMR spectrum; Figure 5 This is the HRMS spectrum of the metal ore collector of Example 1 of the present invention; Figure 6 For the intermediate 1 of Example 2 of the present invention 1 H NMR spectrum; Figure 7 This is the HRMS spectrum of intermediate 1 of Example 2 of the present invention; Figure 8 The metal ore collector of Example 2 of the present invention 1 H NMR spectrum; Figure 9 This is the HRMS spectrum of the metal ore collector of Example 2 of the present invention; Figure 10 For the intermediate 1 of Example 3 of the present invention 1 H NMR spectrum; Figure 11 This is the HRMS spectrum of intermediate 1 of Example 3 of the present invention; Figure 12 The metal ore collecting agent of Example 3 of the present invention 1 H NMR spectrum; Figure 13 This is the HRMS spectrum of the metal ore collector of Example 3 of the present invention. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be further described below in conjunction with specific embodiments. However, it should be understood by those skilled in the art that the following examples are only intended to illustrate the present invention and should not be construed as limiting the present invention. Specific conditions not specified in the examples are to be followed according to conventional conditions or the conditions recommended by the manufacturer. All reagents or instruments used, unless otherwise specified, are conventional products obtained from commercial channels.

[0020] Example 1 A metal ore flotation collector, the structural formula of which is as follows: .

[0021] This embodiment also provides a method for preparing the above-mentioned metal ore flotation collector. The synthesis diagram is shown in FIG. Figure 1 As shown, Figure 1 In the example, n=4, the following steps are included: (1) Sodium hydroxide (68 mmol) was added to water (12 mL), and then 5-hydroxyvaleric acid (33 mmol) was added. The temperature was stabilized to room temperature to obtain a mixed solution. The mixed solution was slowly added to an acetone solution of cyanuric chloride (10 mmol, 10 mL) at 0°C and reacted under stirring for 4 h. After the reaction, the reaction solution was poured into 50 mL of 1M hydrochloric acid solution, and the white solid was collected by filtration. The white solid was then slurried with hot water until there was no obvious impurity spot on the TLC plate of the solid part. After filtration, the intermediate 1 was dried at 80°C to obtain the intermediate 1. 1 H NMR and HRMS spectra are shown in Figure 2 and Figure 3 As shown, 1 HNMR (C 18 H27 N3O9, 400 MHz, DMSO): δ 11.85 (s, 3H), 4.08 (t, 6H), 2.24 (t, 6H), 1.85-1.83 (m, 6H), 1.53-1.51 (m, 6H); HRMS (ESI + ): [M+H] + The calculated value is 430.17, and the found value is 430.18.

[0022] (2) Intermediate 1 (10 mmol) and 6-(methylthio)pyridine-3-amine (45 mmol) were added to anhydrous N,N-dimethylformamide (50 mL), cooled to 0°C, and then N,N,N',N'-tetramethylchloroformamidine hexafluorophosphate (TCFH, 70 mmol) and N-methylimidazole (NMI, 110 mmol) were added. The temperature was gradually raised to room temperature and the reaction was carried out for 14 h. n-heptane (150 mL) was added to the reaction system, stirred evenly, and filtered. The filter cake was dried and added to anhydrous N,N-dimethylformamide (50 mL). Sodium ethylsulfate (38 mmol) was added, and the temperature was raised to 120°C under stirring for 14 h. Pre-HPLC separation was performed to obtain a metal ore beneficiation collector. 1 H NMR and HRMS spectra are shown in Figure 4 and Figure 5 As shown, 1 H NMR (C 33 H 39 N9O6S3,400 MHz, DMSO): δ 12.46 (s, 3H), 9.95 (s, 3H), 7.93 (t, 6H), 7.47 (d, 3H), 4.08 (t, 6H), 2.32 (t, 6H), 1.86-1.84 (m, 6H), 1.53-1.51 (m, 6H); HRMS (ESI + ): [M+H] + The calculation is 754.22, and the result is 754.22.

[0023] Example 2 A metal ore flotation collector, the structural formula of which is as follows: .

[0024] This embodiment also provides a method for preparing the above-mentioned metal ore flotation collector. The synthesis diagram is shown in FIG. Figure 1 As shown, Figure 1 In the example, n=5, the following steps are included: (1) Sodium hydroxide (65 mmol) was added to water (10 mL), and then 6-hydroxyhexanoic acid (32 mmol) was added. The temperature was stabilized to room temperature to obtain a mixed solution. The mixed solution was slowly added to an acetone solution of cyanuric chloride (10 mmol, 10 mL) at 5°C and reacted under stirring for 3 h. After the reaction, the reaction solution was poured into 50 mL of 1 M hydrochloric acid solution, and the white solid was collected by filtration. The white solid was then slurried with hot water until there was no obvious impurity spot on the TLC plate of the solid part. After filtration, the intermediate 1 was dried at 80°C to obtain the intermediate 1. 1 H NMR and HRMS spectra are shown in Figure 6 and Figure 7 As shown, 1 H NMR (C 21 H 33 HRMS (ESI) + ): [M+H] + Calculated to be 472.22, found to be 472.22.

[0025] (2) Intermediate 1 (10 mmol) and 6-(methylthio)pyridine-3-amine (40 mmol) were added to anhydrous N,N-dimethylformamide (50 mL), cooled to 5°C, and then TCFH (60 mmol) and NMI (100 mmol) were added. The temperature was gradually raised to room temperature and the reaction was carried out for 12 h. n-heptane (150 mL) was added to the reaction system, stirred evenly, and filtered. The filter cake was dried and added to anhydrous N,N-dimethylformamide (50 mL). Sodium ethylsulfate (35 mmol) was added, and the temperature was raised to 130°C under stirring for 12 h. Pre-HPLC separation was performed to obtain a metal ore collector. 1 H NMR and HRMS spectra are shown in Figure 8 and Figure 9 As shown, 1 H NMR (C 36 H 45N9O6S3, 400 MHz, DMSO): δ 12.46 (s, 3H), 9.95 (s, 3H), 7.93 (t, 6H), 7.47 (d, 3H), 4.08 (t, 6H), 2.32 (t, 6H), 1.82-1.80 (m, 6H),1.55-1.53 ​​(m, 6H), 1.31-1.29 (m, 6H); HRMS (ESI + ): [M+H] + The calculation is 796.27, and the result is 796.27.

[0026] Example 3 A metal ore flotation collector, the structural formula of which is as follows: .

[0027] This embodiment also provides a method for preparing the above-mentioned metal ore flotation collector. The synthesis diagram is shown in FIG. Figure 1 As shown, Figure 1 In the example, n=6, the following steps are included: (1) Sodium hydroxide (70 mmol) was added to water (15 mL), and then 7-hydroxyheptanoic acid (35 mmol) was added. The temperature was stabilized to room temperature to obtain a mixed solution. The mixed solution was slowly added to an acetone solution of cyanuric chloride (10 mmol, 12 mL) at 0°C and reacted under stirring for 5 h. After the reaction, the reaction solution was poured into 50 mL of 1 M hydrochloric acid solution, and the white solid was collected by filtration. The white solid was then slurried with hot water until there was no obvious impurity spot on the TLC plate of the solid part. After filtration, the intermediate 1 was dried at 80°C to obtain the intermediate 1. 1 H NMR and HRMS spectra are shown in Figure 10 and Figure 11 As shown, 1 H NMR (C 24 H 39 N3O9, 400 MHz, DMSO): δ 11.85 (s, 3H), 4.08 (t, 6H), 2.24 (t, 6H), 1.82-1.80 (m, 6H), 1.55-1.45 (m, 18H); HRMS (ESI + ): [M+H] + The calculated value is 514.27, and the found value is 514.27.

[0028] (2) Intermediate 1 (10 mmol) and 6-(methylthio)pyridine-3-amine (50 mmol) were added to 50 mL of anhydrous N,N-dimethylformamide, cooled to 0°C, and then TCFH (80 mmol) and NMI (120 mmol) were added. The temperature was gradually raised to room temperature and the reaction was carried out for 16 h. n-heptane (150 mL) was added to the reaction system, stirred evenly, and filtered. The filter cake was dried and added to anhydrous N,N-dimethylformamide (50 mL). Sodium ethylsulfate (40 mmol) was added, and the temperature was raised to 110°C under stirring for 16 h. Pre-HPLC separation was performed to obtain a metal ore collector. 1 H NMR and HRMS spectra are shown in Figure 12 and Figure 13 As shown, 1 H NMR (C 39 H 51 N9O6S3, 400 MHz, DMSO): δ 12.46 (s, 3H), 9.95 (s, 3H), 7.93(t, 6H), 7.47 (d, 3H), 4.08 (t, 6H), 2.32 (t, 6H), 1.82-1.80 (m, 6H), 1.55-1.45 (m, 18H); HRMS (ESI + ): [M+H] + The calculation is 838.31, and the result is 838.31.

[0029] Test example The effects of the metal ore flotation collectors prepared in Examples 1-3 of the present invention were verified, and n-butyl sodium xanthate was set as a comparative collector. The specific steps were as follows: (1) Weigh 400 g of low-grade nickel-copper sulfide ore (Ni grade is 0.65%, Cu grade is 0.36%) and grind it to make the content of material with particle size less than 0.074 mm be 65-70%. Then add water to adjust the pulp concentration to 50%, and conduct a flotation experiment. (2) In the first stage flotation experiment, 100 g / t of copper sulfate as an activator was first added, and after slurrying for 2 minutes, 100 g / t of the collector prepared in Example 1-3 or n-butyl sodium xanthate was added. After further slurrying for 2 minutes, 100 g / t of methyl isobutyl carbinol as a foaming agent was added. After slurrying for 2 minutes, 100 g / t of scavenging, 5 minutes of concentrating, and 3 minutes of concentrating were performed to obtain concentrate 1; (3) In the second-stage flotation experiment, the first-stage slurry was re-ground to make the content of materials with a particle size of less than 0.074 mm at 85%, and then 80 g / t of copper sulfate as an activator was added. After slurry mixing for 2 minutes, 80 g / t of the collector prepared in Example 1-3 or n-butyl sodium xanthate was added. After slurry mixing for another 2 minutes, 80 g / t of methyl isobutyl carbinol as a foaming agent was added. After slurry mixing for 2 minutes, 8 minutes of scavenging, 5 minutes of concentrating, and 4 minutes of concentrating were performed to obtain concentrate 2. Then, two more scavengings of 6 minutes and 4 minutes were performed to obtain tailings. (4) The concentrate 1 obtained in step (2) is mixed with the concentrate 2 obtained in step (3) to obtain a copper-nickel mixed concentrate.

[0030] The nickel and copper grades in the copper-nickel mixed concentrate and tailings products were tested using ICP inductively coupled ion emission spectrometry. The results are shown in Table 1.

[0031] Table 1 As can be seen from Table 1, compared with n-butyl sodium xanthate as a collector, the copper and nickel in the copper-nickel mixed concentrate selected using the collectors of Examples 1-3 of the present invention have higher grades, and the recovery rates of copper and nickel are both above 85%. In addition, as the length of the introduced fatty chain increases, the grade and recovery rate increase slightly. The above results show that the collector molecules designed by the present invention can effectively adapt to the characteristics of low-grade nickel-copper sulfide ores and significantly improve the collection effect.

[0032] Analysis of the molecular structure of the collector shows that the sulfur atom of the thiol group in the metal ore flotation collector of the present invention has a strong affinity and can undergo chemical adsorption with metal ions to form a strong metal-sulfur bond; the pyridine group has good electron donor properties and can form a coordination bond with the metal ion; the melamine group has multiple nitrogen atoms and can form a multi-coordinated chelate with the metal ion; the ether bond can increase the flexibility and polarity of the collector molecule, helping the collector molecule to better adapt to the chemical environment of the mineral surface; and the introduced fatty chain can provide hydrophobicity and enhance the adsorption stability of the collector molecule on the mineral surface. The synergistic effect of these functional groups can significantly improve the collector's selective capture ability for metal minerals such as nickel and copper.

[0033] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the same. The basic principles and main features of the present invention have been described above using specific implementation schemes. Modifications or substitutions may be made based on the present invention, but such modifications or substitutions do not detract from the essence of the corresponding technical solutions from the scope of protection claimed by the present invention.

Claims

1. A metal ore flotation collector, characterized in that: The structural formula of the metal ore flotation collector is: Wherein, n is 4, 5 or 6.

2. A method for preparing a metal ore flotation collector according to claim 1, characterized in that: The following steps are involved: (1) Sodium hydroxide and ω-hydroxy fatty acid are added to water to obtain a mixed solution; the mixed solution is added to an acetone solution of cyanuric chloride at 0-5°C and reacted under stirring; after the reaction is completed, intermediate 1 is obtained through post-treatment; The structural formula of the intermediate 1 and ω-hydroxy fatty acid is: Wherein, n is 4, 5 or 6; (2) The intermediate 1 and 6-(methylthio)pyridin-3-amine are added to N,N-dimethylformamide, and N,N,N',N'-tetramethylchloroformamidine hexafluorophosphate and N-methylimidazole are added at 0-5°C, and then the temperature is raised to room temperature for reaction; n-heptane is added to the reaction system, filtered, and the filter residue is added to N,N-dimethylformamide, and sodium ethylsulfate is added, and the reaction is heated under stirring; after the reaction is completed, the metal ore flotation collector is obtained through post-treatment.

3. The method for preparing a metal ore flotation collector according to claim 2, wherein: The molar ratio of sodium hydroxide, ω-hydroxy fatty acid and cyanuric chloride in step (1) is (6.5-7): (3.2-3.5):

1.

4. The method for preparing a metal ore flotation collector according to claim 2, wherein: The reaction time in step (1) is 3-5 h.

5. The method for preparing a metal ore flotation collector according to claim 2, wherein: The molar ratio of the intermediate 1, 6-(methylthio)pyridin-3-amine, N,N,N',N'-tetramethylchloroformamidine hexafluorophosphate, N-methylimidazole and sodium ethylsulfate in step (2) is 1:(4-5):(6-8):(10-12):(3.5-4).

6. The method for preparing a metal ore flotation collector according to claim 2, wherein: The reaction time at room temperature in step (2) is 12-16 h.

7. The method for preparing a metal ore flotation collector according to claim 2, wherein: The heating reaction temperature in step (2) is 110-130°C and the time is 12-16 hours.

8. The method for preparing a metal ore flotation collector according to claim 2, wherein: The post-treatment operation in step (1) is as follows: pouring the reaction solution into a 1 mol / L hydrochloric acid solution, filtering, slurrying the collected filter residue with hot water, filtering again and drying.

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