Method for separating chalcopyrite and molybdenite

Abstract

The invention relates to a method for separating chalcopyrite and molybdenite, which comprises the following steps: mixing chalcopyrite and molybdenite, grinding, putting into a flotation tank of a flotation machine, adding water, and mixing to prepare slurry; adjusting the pH value of the slurry, then adding an oxidizing agent, mixing, then adding ferrite, stirring for 2-10 minutes, then adding a collecting agent and a foaming agent, inflating for flotation, and respectively obtaining concentrate and tailings; wherein the oxidizing agent is peroxymonosulfate and hydrogen peroxide; according to the method, treatment on the surface of the chalcopyrite is strengthened by constructing the synergistic effect of a double-oxidation system, so that the surface of the chalcopyrite is hydrophilic and inhibited, separation of the chalcopyrite and molybdenite is achieved, and the method has important theoretical and practical significance on efficient utilization of the chalcopyrite and the molybdenite.

Description

Technical Field

[0001] The invention relates to the technical field of mineral processing, and more particularly to a method for separating chalcopyrite and molybdenite. Background Art

[0002] Molybdenum is a scarce element. Due to its outstanding advantages such as wear resistance, corrosion resistance, thermal conductivity and electrical conductivity, it is widely used in aerospace, electrical, machinery manufacturing, agriculture, environmental protection and other industries. It has become an important raw material and irreplaceable strategic material in the national economy, and is known as the "war metal".

[0003] Molybdenum minerals are usually associated with copper minerals. Porphyry copper-molybdenum deposits are the main source of copper-molybdenum resources. According to incomplete statistics, nearly 50% of the world's molybdenum is produced from porphyry copper-molybdenum ores. Usually, molybdenite and chalcopyrite are recovered by flotation and then separated from the chalcopyrite-molybdenite mixed concentrate. In the mixed flotation stage, the process adds a collector with strong collection ability, such as butyl xanthate, etc., and the copper-molybdenum sulfide mixed ore adsorbed with the collector is more difficult to separate. In the flotation separation process of copper-molybdenum rough concentrate, the process of "copper suppression and molybdenum flotation" is often used. There are many known chalcopyrite inhibitors, mainly sulfur-containing compound agents, cyanide, Knox and thiol compound inhibitors, but these inhibitors are highly toxic and costly, and have great harmful effects on human health and the environment. Therefore, it is urgent to develop a green and environmentally friendly copper-molybdenum separation method.

[0004] For example, patent application CN202211110671.4 discloses a method for separating molybdenite and chalcopyrite based on surface oxidation. This method uses the characteristics of hydrogen peroxide and the dissolved product obtained by oxidation reaction on the surface of molybdenite to selectively inhibit chalcopyrite but not molybdenite, so as to achieve flotation separation of molybdenite and chalcopyrite. However, the oxidation capacity of a single oxidant is limited, the activation efficiency is low, and ultrasound assistance is required to react as much as possible; and hydrogen peroxide is easily decomposed into O2 and H2O under neutral or alkaline conditions, further weakening the effect it should have, and the effect is not obvious in industry, and it is not suitable for industrial application. Patent application CN202310692913.3 discloses a method for separating copper-molybdenum mixed concentrate by advanced oxidation flotation. This method generates highly active sulfate radicals and hydroxyl radicals by adding persulfate and divalent iron salts to the system, reducing the difficulty of copper-molybdenum separation, and oxidizing chalcopyrite at the same time, inhibiting chalcopyrite without affecting molybdenite, and achieving separation of chalcopyrite and molybdenite. However, single persulfate also has a narrow pH range of application and limited oxidation capacity. The Fe 3+ It is easy to generate precipitation under alkaline conditions, which reduces the original effect. Summary of the invention

[0005] Based on the above technical problems existing in the prior art, the present invention provides a method for separating chalcopyrite and molybdenite. The method constructs a dual oxidation system for synergistic effect, strengthens the treatment of the chalcopyrite surface, makes the chalcopyrite surface hydrophilic and inhibited, and realizes the separation of chalcopyrite and molybdenite. The method has important theoretical and practical significance for the efficient utilization of chalcopyrite and molybdenite.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] A method for separating chalcopyrite and molybdenite comprises the following steps:

[0008] S1, mixing chalcopyrite and molybdenite, grinding them, and then putting them into the flotation cell of a flotation machine, adding water and mixing them into a slurry;

[0009] S2, adjusting the pH of the slurry, then adding an oxidant and mixing, and then adding ferrous salt, stirring for 2-10 minutes, adding a collector and a frother, aerating for flotation, and obtaining concentrate and tailings respectively;

[0010] Wherein, the oxidant is peroxymonosulfate and hydrogen peroxide.

[0011] In some embodiments, the amount of hydrogen persulfate used is 100-200 mg / L.

[0012] In some embodiments, the amount of hydrogen peroxide is 100-200 mg / L.

[0013] In some embodiments, the amount of ferrous salt is 100-200 mg / L.

[0014] In some embodiments, the peroxymonosulfate, hydrogen peroxide and ferrous salt are each prepared into a 4 g / L solution and added.

[0015] In some embodiments, in step S2, the pH of the slurry is adjusted to 6-8.

[0016] In some embodiments, the collector is kerosene, and the dosage is 10-30 mg / L.

[0017] In some embodiments, the foaming agent is MIBC, and the dosage is 10-30 mg / L.

[0018] In some embodiments, the collector is prepared into a 400 mg / L solution for addition; and MIBC is prepared into a 400 mg / L solution for addition.

[0019] In some embodiments, in step S1, the mixed ore of chalcopyrite and molybdenite is ground to a fineness of 38-74 μm.

[0020] In some embodiments, the mass ratio of the mixed ore of chalcopyrite and molybdenite to water is 1:30-50.

[0021] In some embodiments, the peroxymonosulfate salt is potassium peroxymonosulfate salt and / or sodium peroxymonosulfate salt.

[0022] In some embodiments, the ferrous salt includes but is not limited to at least one of ferrous sulfate, ferrous nitrate, ferrous chloride, and ferrous hydroxide.

[0023] In some embodiments, the method specifically comprises the following steps:

[0024] S1. Mix chalcopyrite and molybdenite, grind them to a fineness of 38-74 μm, put them into the flotation cell of a flotation machine, and add water to mix;

[0025] S2. After stirring and slurrying for 1-3 minutes, add pH regulator to adjust the pH of the slurry, then add oxidant, stir for 30-60 seconds, add ferrous salt, stir for 2-5 minutes; then add collector and stir for 2-5 minutes, add frother and stir for 2-5 minutes, aerate for flotation to obtain concentrate and tailings.

[0026] In some embodiments, the pH adjuster is sodium hydroxide and hydrochloric acid.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention constructs a dual oxidation system by adding peroxymonosulfate and hydrogen peroxide into a flotation system. The two oxides are mutually excited to promote the chain reaction and the generation of free radicals. Under the same reagent concentration, the dual oxidation system can generate sulfate radicals and hydroxyl radicals with stronger oxidation ability than the single oxidation system. The two have a synergistic effect, which can strengthen the oxidation of the chalcopyrite surface, so that Fe and Cu elements on the chalcopyrite surface generate hydrophilic substances such as oxides, hydroxides and sulfates, thereby enhancing the inhibition effect on the chalcopyrite.

[0029] This patent uses hydrogen persulfate and hydrogen peroxide to construct a dual oxidation system to achieve clean flotation separation of copper-molybdenum sulfide ores. It can achieve good oxidation effect in a neutral environment, and hydrogen persulfate has stronger oxidation ability than peroxydisulfate. After dissolution, it produces various highly active small molecule free radicals, active oxygen and other derivatives, which can provide super strong and effective oxidation potential. It is safe, convenient to use and has good stability.

[0030] The method of the present invention can separate chalcopyrite and molybdenite without ultrasonic assistance, and can achieve complete separation of copper and molybdenum. A high-grade concentrate can be obtained through one flotation. The process is simple, the recovery rate is high, the cost is low, and it is suitable for industrial application. DETAILED DESCRIPTION

[0031] Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar modifications without violating the connotation of the present invention, so the present invention is not limited to the specific implementation disclosed below.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0033] Example 1

[0034] A method for separating chalcopyrite and molybdenite, comprising the following steps:

[0035] S1. Grind the molybdenite and chalcopyrite samples to 38-74 μm, put the ground molybdenite and chalcopyrite into a flotation tank in a weight ratio of 1:1, and add appropriate amount of water for stirring;

[0036] S2. After stirring and slurrying for 1 minute, add a pH adjuster to adjust the pH to 7.0, add 100 mg / L of peroxymonosulfate and 100 mg / L of hydrogen peroxide, stir for 30 seconds, add 100 mg / L of ferrous salt and stir for 3 minutes, add 10 mg / L of kerosene and stir for 3 minutes, add 10 mg / L of frother and stir for 2 minutes, then aerate for flotation, the foam product is the concentrate, and the product in the tank is the tailings.

[0037] The flotation results are shown in Table 1.

[0038] Table 1 Flotation index of artificial mixed ore under dual oxidation system (%)

[0039]

[0040]

[0041] Comparative Example 1

[0042] A method for separating chalcopyrite and molybdenite, comprising the following steps:

[0043] S1. Grind the molybdenite and chalcopyrite samples to 38-74 μm, put the ground molybdenite and chalcopyrite into a flotation tank in a weight ratio of 1:1, and add appropriate amount of water for stirring;

[0044] S2. After stirring and slurrying for 1 minute, add a pH adjuster to adjust the pH to about 7, add 200 mg / L of hydrogen persulfate and 100 mg / L of ferrous salt in succession, stir for 3 minutes, add 10 mg / L of kerosene, stir for 3 minutes, add 10 mg / L of frother, stir for 2 minutes, and aerate for flotation. The foam product is the concentrate, and the product in the tank is the tailings.

[0045] The flotation results are shown in Table 2.

[0046] Table 2 Flotation index of artificial mixed ore under peroxymonosulfate system (%)

[0047]

[0048] Comparative Example 2

[0049] A method for separating chalcopyrite and molybdenite, comprising the following steps:

[0050] S1. Grind the molybdenite and chalcopyrite samples to 38-74 μm, put the ground molybdenite and chalcopyrite into a flotation tank in a weight ratio of 1:1, and add appropriate amount of water for stirring;

[0051] S2. After stirring and slurrying for 1 minute, add a pH adjuster to adjust the pH to about 7, add 200 mg / L of hydrogen peroxide and 100 mg / L of ferrous salt successively and stir for 3 minutes, add 10 mg / L of kerosene and stir for 3 minutes, add 10 mg / L of frother and stir for 2 minutes, then aerate for flotation, the foam product is the concentrate, and the product in the tank is the tailings.

[0052] The flotation results are shown in Table 3.

[0053] Table 3 Flotation index of artificial mixed ore under hydrogen peroxide system (%)

[0054]

[0055] From the flotation test results of artificial mixed ores in Example 1 and Comparative Example 2, it can be seen that a concentrate with a molybdenum grade of 34.21% and a copper grade of 14.91% can be obtained under a single persulfate oxidation system; a concentrate with a molybdenum grade of 33.84% and a copper grade of 15.60% can be obtained under a single hydrogen peroxide oxidation system; and under a dual oxidation system, a concentrate with a molybdenum grade and a recovery rate of 49.84% and 91.67%, respectively, and a copper grade and a recovery rate of 3.67% and 11.81%, respectively, can be obtained.

[0056] The above results show that at the same reagent concentration, the dual oxidation system can reduce the mutual content of copper and molybdenum in the concentrate product, improve the grade of molybdenum concentrate, and have better separation indicators than the single oxidation system. This scheme can enhance the flotation separation of chalcopyrite and molybdenite.

[0057] The results of the implementation case show that the method based on the synergistic oxidation of sulfate radicals and hydroxyl radicals to enhance the separation of chalcopyrite and molybdenite has a synergistic effect compared to the single oxidation system under the same reagent concentration. The oxidants in the dual oxidation system excite each other, promote the chain reaction, and promote the generation of sulfate radicals and hydroxyl radicals. This system can enhance the surface oxidation of chalcopyrite, make up for the deficiency of a single oxidant, enhance the inhibitory effect on chalcopyrite, and have better selectivity in the flotation separation of molybdenite and chalcopyrite, and can effectively maximize the reagent effect. This solution is highly efficient, green and environmentally friendly, and has significant effects.

[0058] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0059] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for separating chalcopyrite and molybdenite, characterized in that: The following steps are involved: S1, mixing chalcopyrite and molybdenite, grinding them, and then putting them into the flotation cell of a flotation machine, adding water and mixing them into a slurry; S2, adjusting the pH of the slurry, then adding an oxidant and mixing, and then adding ferrous salt, stirring for 2-10 minutes, adding a collector and a frother, aerating for flotation, and obtaining concentrate and tailings respectively; Wherein, the oxidant is peroxymonosulfate and hydrogen peroxide.

2. The method for separating chalcopyrite and molybdenite according to claim 1, characterized in that: The dosage of the peroxymonosulfate is 100-200 mg / L; the dosage of the hydrogen peroxide is 100-200 mg / L; and the dosage of the ferrous salt is 100-200 mg / L.

3. The method for separating chalcopyrite and molybdenite according to claim 2, characterized in that: The peroxymonosulfate, hydrogen peroxide and ferrous salt are respectively prepared into 4 g / L solutions for addition.

4. The method for separating chalcopyrite and molybdenite according to claim 1, characterized in that: In step S2, the pH of the slurry is adjusted to 6-8.

5. The method for separating chalcopyrite and molybdenite according to claim 1, characterized in that: The collector is kerosene, and the dosage is 10-30 mg / L; the foaming agent is methyl isobutyl carbinol (MIBC), and the dosage is 10-30 mg / L.

6. The method for separating chalcopyrite and molybdenite according to claim 5, characterized in that: The collector was prepared into a 400 mg / L solution and added; MIBC was prepared into a 400 mg / L solution and added.

7. The method for separating chalcopyrite and molybdenite according to claim 1, characterized in that: In step S1, the mixed ore of chalcopyrite and molybdenite is ground to a fineness of 38-74 μm.

8. The method for separating chalcopyrite and molybdenite according to claim 1, characterized in that: The mass ratio of the mixed ore of chalcopyrite and molybdenite to water is 1:30-50.

9. The method for separating chalcopyrite and molybdenite according to claim 1, characterized in that: The peroxymonosulfate salt is potassium peroxymonosulfate salt and / or sodium peroxymonosulfate salt.

10. The method for separating chalcopyrite and molybdenite according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Mix chalcopyrite and molybdenite, grind them to a fineness of 38-74 μm, put them into the flotation cell of a flotation machine, and add water to mix; S2. After stirring and slurrying for 1-3 minutes, add pH regulator to adjust the pH of the slurry, then add oxidant, stir for 30-60 seconds, add ferrous salt, stir for 2-5 minutes; then add collector and stir for 2-5 minutes, add frother and stir for 2-5 minutes, aerate for flotation to obtain concentrate and tailings.

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