Synthesis method of gold ore flotation auxiliary collecting agent and gold ore beneficiation method

Abstract

The invention discloses a synthesis method of a gold ore flotation auxiliary collecting agent and a gold ore beneficiation method. The synthesis method of the gold ore flotation auxiliary collecting agent comprises the step that dibromoalkane and a vulcanizing agent react in a mixed solvent of an organic solvent and water, and the gold ore flotation auxiliary collecting agent is synthesized. The bifunctional mercaptan auxiliary collecting agent obtained through synthesis is combined with a traditional xanthate collecting agent for use, the agent collecting performance is improved through the strong bonding effect of-SH groups in the auxiliary collecting agent and active sites on the surfaces of gold-loaded minerals, and therefore the gold ore flotation index is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of mineral processing, and in particular to a method for synthesizing a gold ore flotation auxiliary collector and a gold ore beneficiation method. Background Art

[0002] Gold has many excellent physical and chemical properties. It is widely used in high-tech fields such as aviation, aerospace, information technology, medicine, and electricity. In recent years, as easy-to-select gold mines have been exhausted, the current collectors have insufficient collection performance for ores with complex properties and difficult to select, and often cannot meet production needs. Therefore, the research and development of new gold flotation collectors is crucial. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a method for synthesizing a gold flotation auxiliary collector and a gold ore beneficiation method.

[0004] The present invention solves the technical problem by adopting the following technical solutions.

[0005] The invention provides a method for synthesizing an auxiliary collector for gold ore flotation, which comprises: reacting dibromoalkane and a sulfiding agent in a mixed solvent of an organic solvent and water to synthesize the auxiliary collector for gold ore flotation.

[0006] The present invention also provides a gold ore beneficiation method using the above-mentioned gold ore flotation auxiliary collector, which comprises: mixing the above-mentioned gold ore flotation auxiliary collector with a traditional collector and adding them into the gold ore flotation slurry to perform gold ore flotation.

[0007] The present invention has the following beneficial effects:

[0008] The present invention provides a method for synthesizing a gold flotation auxiliary collector and a gold ore beneficiation method. The method for synthesizing a gold flotation auxiliary collector provided by the present invention comprises: reacting a dibromoalkane and a sulfiding agent in a mixed solvent of an organic solvent and water to synthesize a gold flotation auxiliary collector. The bifunctional thiol auxiliary collector synthesized above is rationally assembled with a traditional xanthate collector, and the strong bonding between the thiol group in the auxiliary collector and the active site on the surface of the main gold-bearing mineral strengthens the adsorption performance of the traditional collector on the surface of the gold-bearing mineral, thereby reducing the tailings grade and improving the gold flotation recovery rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0010] Figure 1 It is a schematic diagram of the gold ore flotation process in the present invention. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0012] The following is a detailed description of a method for synthesizing a gold flotation auxiliary collector and a gold ore beneficiation method provided by an embodiment of the present invention.

[0013] In a first aspect, an embodiment of the present invention provides a method for synthesizing an auxiliary collector for gold flotation, comprising: reacting a dibromoalkane and a sulfiding agent in a mixed solvent of an organic solvent and water to synthesize the auxiliary collector for gold flotation.

[0014] In some optional embodiments, the dibromoalkane is an α, ω-dibromoalkane, and preferably the carbon number of the α, ω-dibromoalkane is 5 to 18. Exemplarily, the α, ω-dibromoalkane can be one or more of 1,5-dibromopentane, 1,6-dibromohexane, 1,7-dibromoheptane, 1,8-dibromooctane, 1,9-dibromononane, 1,10-dibromodecane, 1,11-dibromodeundecane, 1,12-dibromodedodecane, 1,13-dibromodetridecane, 1,14-dibromodetetradecane, 1,15-dibromopentadecane, 1,16-dibromohexadecane, 1,17-dibromoheptadecane, and 1,18-dibromooctadecane.

[0015] In some optional embodiments, the vulcanizing agent includes at least one of sodium isopropyl xanthate, sodium ethyl xanthate, S8, and Na2S.

[0016] In some optional embodiments, the organic solvent includes at least one of N,N-dimethylformamide, toluene, dimethylacetamide, and N-methylpyrrolidone.

[0017] In some optional embodiments, the molar ratio of dibromoalkane, sulfiding agent, organic solvent and water is 1:2:(50-80):(50-80).

[0018] In some optional embodiments, the reaction temperature is 120-200° C., and the reaction time is 12-36 h.

[0019] In some optional embodiments, the method further comprises: after the reaction is completed, cooling the reaction solution to room temperature, adding saturated brine, then adding ethyl acetate for extraction, and then taking the upper organic phase, performing vacuum distillation and chromatography separation and purification to obtain a gold flotation auxiliary collector.

[0020] In some optional embodiments, 1,5-dibromopentane, sodium isopropyl xanthate, N,N-dimethylformamide (DMF) and water are sequentially placed in a reactor at a molar ratio of 1:2:60:60, and the mixture is reacted at 130° C. for 24 hours. The reaction process is shown in the following formula.

[0021]

[0022] In a second aspect, an embodiment of the present invention further provides a gold ore beneficiation method, which comprises: mixing the above-mentioned gold ore flotation auxiliary collector with a traditional collector and adding them into the gold ore flotation slurry to carry out gold ore flotation, and enhancing the capture of gold-bearing minerals through the strong bonding between the -SH groups in the auxiliary collector and the active sites on the surface of the main gold-bearing mineral pyrite, thereby compensating for the defect of insufficient capture capacity of traditional xanthate collectors in the gold ore flotation process.

[0023] In some optional embodiments, the steps include: crushing and grinding the gold-containing raw ore sample, adding water to obtain gold ore slurry, adding a dispersant, an activator, a gold flotation auxiliary collector, a traditional collector and a frother to the gold ore slurry, and flotating the gold ore to obtain gold concentrate and tailings.

[0024] In some optional embodiments, the flotation process includes 1 roughing selection, 2 scavenging selections, and 2 cleaning selections.

[0025] In some optional embodiments, the dispersant includes one or more of sodium carbonate and water glass, and the preferred amount of the adjuster is 0-1000 g / t; the activator is copper sulfate, and the preferred amount of the activator is 0-1000 g / t; the traditional collector includes one or more of yellow medicine collectors and black medicine collectors, and the preferred amount of the traditional collector is 20-200 g / t; the amount of the gold flotation auxiliary collector is 5-20 g / t; the frother includes one or more of 2# oil, MIBC or RB-3, and the preferred amount of the frother is 10-50 g / t.

[0026] In some optional embodiments, gold ore pulp is prepared by the following method: the gold-containing raw ore sample is crushed to -2mm by a crusher, and then ground, the grinding concentration is 50-70%, and the grinding fineness is -0.074mm accounting for 55-80%; the ground slurry sample is transferred to a flotation machine, water is added to adjust the slurry concentration to 25-40%, and gold ore slurry is obtained.

[0027] The present invention will be further described below in conjunction with the embodiments.

[0028] 1. Synthesis method of gold flotation auxiliary collector:

[0029] (1) 1,5-dibromopentane, sodium isopropyl xanthate, N,N-dimethylformamide (DMF) and water were placed in a reactor in a molar ratio of 1:2:60:60, and reacted at 130° C. for 24 hours.

[0030] (2) After the reaction is completed, the mixture is cooled to room temperature, saturated brine is added, and then ethyl acetate is added for extraction. The upper organic phase is taken and purified by vacuum distillation and chromatography separation to obtain 1,5-dimercaptopentane auxiliary collector.

[0031] 2. A gold ore dressing method, such as Figure 1 As shown, the following steps are included:

[0032] (1) Use a crusher to crush the gold-containing ore sample to -2 mm;

[0033] (2) Grind the gold ore sample in step 1 in a ball mill, with a grinding concentration of 50-70% and a grinding fineness of -0.074 mm accounting for 55-80%;

[0034] (3) Transfer the finely ground pulp sample in step 2 to a flotation machine and add water to adjust the pulp concentration to 25-40%;

[0035] (4) Adding a regulator, an activator, a conventional collector, the auxiliary collector of the present invention and a frother to the slurry obtained in step 3 to carry out gold ore flotation, wherein the flotation process comprises 1 roughing selection, 2 scavenging selections and 2 concentrating selections to obtain gold concentrate and tailings;

[0036] Wherein, in step 4: the adjusting agent includes one or more of sodium carbonate and water glass, and the preferred amount of the adjusting agent is 0-1000g / t; the activating agent is copper sulfate, and the preferred amount of the activating agent is 0-1000g / t; the collecting agent includes one or more of yellow medicine collectors and black medicine collectors, and the preferred amount of the collecting agent is 20-200g / t; the auxiliary collecting agent is 1,5-dimercaptopentane, and the preferred amount of the auxiliary collecting agent is 5-20g / t; the foaming agent includes one or more of 2# oil, MIBC or RB-3, and the preferred amount of the foaming agent is 10-50g / t.

[0037] Example 1

[0038] A gold ore dressing method, such as Figure 1 As shown, the following steps are included:

[0039] (1) Take a gold ore with an Au grade of 1.17 g / t and crush the sample to -2 mm using a crusher;

[0040] (2) Take 500g of ore sample and grind it in a ball mill. The grinding concentration is 62.5% and the grinding fineness is -0.074mm, accounting for 60%;

[0041] (3) Transfer the milled pulp to a 1.5L flotation tank, add water to adjust the pulp concentration to about 25-35%, and stir for 3 minutes at a stirring speed of 1900 rpm;

[0042] (4) Add 40 g / t copper sulfate to the slurry and stir for 3 minutes;

[0043] (5) Add 90 g / t of butyl xanthate and 10 g / t of the 1,5-dimercaptopentane auxiliary collector synthesized by the present invention to the slurry and stir for 3 minutes;

[0044] (6) Add 30g / t of 2# oil to the slurry and stir for 1 minute;

[0045] (7) aeration flotation for 3 minutes to obtain roughing concentrate and roughing tailings products;

[0046] (8) The coarse concentrate is cleaned twice; the tailings are scavenged twice, and the intermediate ore is returned in sequence to obtain the final concentrate and tailings.

[0047] Example 2

[0048] A gold ore dressing method, such as Figure 1 As shown, the following steps are included:

[0049] (1) Take a gold ore with an Au grade of 1.17 g / t and crush the sample to -2 mm using a crusher;

[0050] (2) Take 500g of ore sample and grind it in a ball mill. The grinding concentration is 62.5% and the grinding fineness is -0.074mm, accounting for 60%;

[0051] (3) Transfer the milled pulp to a 1.5L flotation tank, add water to adjust the pulp concentration to about 25-35%, and stir for 3 minutes at a stirring speed of 1900 rpm;

[0052] (4) Add 40 g / t copper sulfate to the slurry and stir for 3 minutes;

[0053] (5) Add 90 g / t of butyl xanthate and 10 g / t of the 1,18-dimercaptooctadecane auxiliary collector synthesized by the present invention to the slurry and stir for 3 minutes;

[0054] (6) Add 30g / t of 2# oil to the slurry and stir for 1 minute;

[0055] (7) aeration flotation for 3 minutes to obtain roughing concentrate and roughing tailings products;

[0056] (8) The coarse concentrate is cleaned twice; the tailings are scavenged twice, and the intermediate ore is returned in sequence to obtain the final concentrate and tailings.

[0057] Comparative Example 1

[0058] A gold ore dressing method, such as Figure 1 As shown, the following steps are included:

[0059] (1) Take a gold ore with an Au grade of 1.17 g / t and crush the sample to -2 mm using a crusher;

[0060] (2) Take 500g of ore sample and grind it in a ball mill. The grinding concentration is 62.5% and the grinding fineness is -0.074mm, accounting for 60%;

[0061] (3) Transfer the milled pulp to a 1.5L flotation tank, add water to adjust the pulp concentration to about 25-35%, and stir for 3 minutes at a stirring speed of 1900 rpm;

[0062] (4) Add 40 g / t copper sulfate to the slurry and stir for 3 minutes;

[0063] (5) Add 100 g / t of butyl xanthate to the slurry and stir for 3 minutes;

[0064] (6) Add 30g / t of 2# oil to the slurry and stir for 1 minute;

[0065] (7) aeration flotation for 3 minutes to obtain rougher concentrate and rougher tailings products;

[0066] (8) The coarse concentrate is cleaned twice; the tailings are scavenged twice, and the intermediate ore is returned in sequence to obtain the final concentrate and tailings.

[0067] Comparative Example 2

[0068] A gold ore dressing method, such as Figure 1 As shown, the following steps are included:

[0069] (1) Take a gold ore with an Au grade of 1.17 g / t and crush the sample to -2 mm using a crusher;

[0070] (2) Take 500g of ore sample and grind it in a ball mill. The grinding concentration is 62.5% and the grinding fineness is -0.074mm, accounting for 60%;

[0071] (3) Transfer the milled pulp to a 1.5L flotation tank, add water to adjust the pulp concentration to about 25-35%, and stir for 3 minutes at a stirring speed of 1900 rpm;

[0072] (4) Add 40 g / t copper sulfate to the slurry and stir for 3 minutes;

[0073] (5) Add 80 g / t of butyl xanthate and 20 g / t of butylamine black medicine into the slurry and stir for 3 minutes;

[0074] (6) Add 30g / t of 2# oil to the slurry and stir for 1 minute;

[0075] (7) aeration flotation for 3 minutes to obtain roughing concentrate and roughing tailings products;

[0076] (8) The coarse concentrate is cleaned twice; the tailings are scavenged twice, and the intermediate ore is returned in sequence to obtain the final concentrate and tailings.

[0077] Table 1 Flotation results in Examples and Comparative Examples

[0078]

[0079] From the above experimental results, it can be seen that by comparing Example 1 with Example 2, as the carbon chain lengthens, the effect of the long carbon chain auxiliary collector on the improvement of the flotation recovery rate of gold ore is more significant. In Comparative Example 1, only butyl xanthate is used as a collector. Compared with Comparative Example 1, the addition of an auxiliary collector in Example 2 can increase the flotation recovery rate of gold ore by 10.38%, and the concentrate grade only drops from 48.25g / t to 45.05g / t. In Comparative Example 2, only the conventional butyl xanthate / butylamine black medicine combined collector is used. Compared with Comparative Example 2, the addition of an auxiliary collector in Example 2 can increase the flotation recovery rate of gold ore by 5.96%, and the concentrate grade only drops from 46.51g / t to 45.05g / t. It can be seen from the above that the assembly combination of the bifunctional auxiliary collector provided by the embodiment of the present invention and the traditional xanthate collector can enhance the collector performance by introducing -SH groups, make up for the shortcoming of insufficient collector capacity of a single xanthate collector, and significantly improve the flotation recovery rate of gold ore.

[0080] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for synthesizing a gold flotation auxiliary collector, characterized in that: It includes: The dibromoalkane and the sulfiding agent are reacted in a mixed solvent of an organic solvent and water to synthesize the gold ore flotation auxiliary collector.

2. The synthesis method according to claim 1, characterized in that The dibromoalkane is an α, ω-dibromoalkane, preferably the α, ω-dibromoalkane has 5-18 carbon atoms, the vulcanizing agent includes at least one of sodium isopropyl xanthate, sodium ethyl xanthate, S8, and Na2S, and the organic solvent includes at least one of N,N-dimethylformamide, toluene, dimethylacetamide, and N-methylpyrrolidone.

3. The synthesis method according to claim 1, characterized in that The molar ratio of the dibromoalkane, the sulfiding agent, the organic solvent and the water is 1:2:(50-80):(50-80).

4. The synthesis method according to claim 1, characterized in that The reaction temperature is 120-200°C and the reaction time is 12-36h.

5. The synthesis method according to claim 1, characterized in that The method also includes: after the reaction is completed, cooling the reaction solution to room temperature, adding saturated brine, then adding ethyl acetate for extraction, and then taking the upper organic phase, performing vacuum distillation and chromatography separation and purification to obtain a gold flotation auxiliary collector.

6. A gold ore dressing method, characterized in that: It includes: The gold ore flotation auxiliary collector according to any one of claims 1 to 5 is mixed with a traditional collector and added into the gold ore flotation slurry to carry out gold ore flotation.

7. The gold ore dressing method according to claim 6, characterized in that: The following steps are involved: The gold-containing raw ore sample is crushed and ground, and then water is added to obtain gold ore pulp. A regulator, an activator, a gold flotation auxiliary collector, a traditional collector and a frother are added to the gold ore pulp to perform gold flotation to obtain gold concentrate and tailings.

8. The gold ore dressing method according to claim 7, characterized in that: The flotation process is 1 roughing selection, 2 scavenging selections and 2 cleaning selections.

9. The gold ore dressing method according to claim 7, characterized in that: The adjusting agent includes one or more of sodium carbonate and water glass, and the dosage of the adjusting agent is preferably 0-1000g / t; the activating agent is copper sulfate, and the dosage of the activating agent is preferably 0-1000g / t; the traditional collector includes one or more of yellow medicine collectors and black medicine collectors, and the dosage of the traditional collector is preferably 20-200g / t; the dosage of the gold flotation auxiliary collector is 5-20g / t; the frother includes one or more of 2# oil, MIBC or RB-3, and the dosage of the frother is preferably 10-50g / t.

10. The gold ore dressing method according to claim 7, characterized in that: The gold ore pulp is prepared by the following method: crushing the gold-containing raw ore sample to -2 mm with a crusher, then grinding, the grinding concentration is 50-70%, and the grinding fineness is -0.074 mm, accounting for 55-80%; transferring the ground pulp sample to a flotation machine, adding water to adjust the pulp concentration to 25-40%, and obtaining the gold ore pulp.

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