Copper sulfide mineral hydrophilic agents and their preparation and application methods

Abstract

This invention provides a copper sulfide mineral hydrophilic agent and its preparation and application method. The method involves adding dichloroethylbenzene and sodium hypochlorite to a reaction vessel, adjusting the pH value of the solution with sodium hydroxide, and raising the temperature of the reaction vessel to a predetermined temperature to initiate the reaction. After the reaction is complete, thiourea is added to the reaction vessel, and the temperature is maintained to continue the reaction. After the final reaction, sodium hydroxide solution is added, and the temperature is maintained to continue the reaction. Finally, the mixture is cooled to room temperature to obtain the copper sulfide mineral hydrophilic agent. The copper sulfide mineral hydrophilic agent prepared by this invention effectively inhibits both primary and secondary copper minerals. When used in molybdenum ore flotation, it can reduce the copper content in molybdenum concentrate. It also features low dosage, significant improvement of the hydrophilicity of copper sulfide without further adjustment of pulp potential and pH, convenient production control, no by-products during preparation, and no environmental pollution during production.

Description

Technical Field

[0001] This invention relates to the field of mineral flotation technology, and in particular to a copper sulfide mineral hydrophilic agent and its preparation and application methods. Background Technology

[0002] In the flotation process of molybdenum ore, copper sulfide minerals (such as chalcopyrite and chalcocite) and molybdenite often exhibit similar flotation behaviors. The adsorption and effect of flotation reagents (such as collectors and frothers) on the surface of ore particles are important factors in the flotation process. The key to separating the two types of minerals is to expand the difference in the physicochemical properties of the mineral surfaces, the core of which is to change the hydrophilic / hydrophobic properties of the mineral surfaces. In conventional molybdenum ore beneficiation, sodium sulfide, sodium hydrosulfide, Knox, and sodium mercaptoacetate are often used as inhibitors for copper minerals. Their mechanism is to make the copper mineral surface hydrophilic. However, the use of the above reagents not only has the characteristics of large reagent dosage, low efficiency, and poor selectivity, but also seriously deteriorates the flotation operating environment, which is not conducive to safe and environmentally friendly production. Therefore, the development of efficient hydrophilic agents for copper sulfide minerals is the key to solving the above problems.

[0003] Mineral processing workers have conducted extensive research on hydrophilic agents for copper sulfide. Chinese patent CN105537002A discloses the preparation and application of a flotation separation inhibitor for copper-molybdenum mixed concentrate, using thiol-chitosan for copper-molybdenum separation. Chinese patent CN109482357A discloses the preparation and application of a copper-molybdenum separation inhibitor, which involves dehydrating and condensing thioglycolic acid and monoethanolamine under stirring at 90-100℃ and sulfuric acid catalysis to synthesize thiol-acetamide. Chinese patent CN110038729A discloses a composite flotation inhibitor for chalcopyrite and a chalcopyrite flotation method, using a Cu-containing reagent. 2+ The compound and thiomalic acid were used as a composite agent. Although this agent had a good inhibitory effect on chalcopyrite, its effect on molybdenite was unclear. Due to various factors, the above-mentioned patent failed to achieve true agent substitution and industrial application. Therefore, developing a hydrophilic agent with strong hydrophilicity to copper sulfide ores is an important issue that urgently needs to be solved in the mineral processing field.

[0004] In view of this, it is necessary to design an improved hydrophilic agent for copper sulfide minerals and its preparation and application methods to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of the existing technology, the present invention aims to provide a copper sulfide mineral hydrophilic agent and its preparation and application method, thereby achieving safe, environmentally friendly and efficient separation of copper sulfide and molybdenum sulfide.

[0006] To achieve the above objectives, the present invention provides a method for preparing a copper sulfide mineral hydrophilic agent, comprising the following steps: S1. Add dichloroethylbenzene and sodium hypochlorite to the reactor, add sodium hydroxide to adjust the pH of the solution, and start the reaction after raising the temperature inside the reactor to the predetermined temperature; S2. After the reaction is complete, add thiourea to the reactor, keep the temperature inside the reactor constant, and continue the reaction; S3. Weigh a predetermined amount of sodium hydroxide, prepare a sodium hydroxide solution, add it to the reaction vessel, keep the temperature inside the reaction vessel constant, and cool to room temperature after the reaction is completed to obtain copper sulfide mineral hydrophilic agent.

[0007] As a further improvement of the present invention, in step S1, the mass ratio of dichloroethylbenzene to sodium hypochlorite is (1.1~1.2):1, and the pH value of the solution is adjusted to 9~11.

[0008] Furthermore, the predetermined temperature is 65~85℃, and the reaction time is 1~3h.

[0009] As a further improvement of the present invention, in step S2, the mass ratio of the thiourea to the sodium hypochlorite in step S1 is (0.9~1.1):1, and the reaction time is 1~3h.

[0010] As a further improvement of the present invention, in step S3, the mass ratio of sodium hydroxide to sodium hypochlorite in step S1 is (0.4~0.6):1.

[0011] Furthermore, the concentration of the sodium hydroxide solution is 4-6 mol / L, and the reaction time is 1-3 h.

[0012] The present invention also provides a copper sulfide mineral hydrophilic agent, which is prepared according to the above-described method for preparing copper sulfide mineral hydrophilic agents.

[0013] The prepared copper sulfide mineral hydrophilic agent is used as a depressant in the flotation of molybdenum ore, including the following steps: S1. Add -2mm molybdenum ore to a ball mill and grind until the ore content of -0.074mm is 80%~85%, and adjust the slurry mass concentration to 30%~35%; S2. Perform two coarse selections and four sweep selections in sequence; S3. After the rough concentrate is regrinded in a ball mill to a content of 80%~85% in -0.045mm, it enters a sixth cleaning operation. The concentrate from the sixth cleaning operation is molybdenum concentrate. S4. The middlings produced by the selection and scavenging operations are returned to the previous operation in sequence to form a closed loop.

[0014] As a further improvement of the present invention, the molybdenum ore has a molybdenum grade of 0.03~0.25% and a copper grade of <0.2%.

[0015] As a further improvement of the present invention, in step S2, the amount of inhibitor used in the coarse selection is 80~120g / t, and the amount of inhibitor used in the sweep selection is 20~70g / t; in step S3, the amount of inhibitor used in the fine selection is 0~80g / t.

[0016] The beneficial effects of this invention are: (1) This invention provides a copper sulfide mineral hydrophilic agent and its preparation and application method. The method involves adding dichloroethylbenzene and sodium hypochlorite to a reaction vessel, adjusting the pH of the solution with sodium hydroxide, raising the temperature inside the reaction vessel to a predetermined temperature, and then initiating the reaction. After the reaction is complete, thiourea is added, and the temperature inside the reaction vessel is kept constant to continue the reaction. Then, sodium hydroxide solution is added to react, and after the reaction is complete, the mixture is cooled to room temperature to obtain the copper sulfide mineral hydrophilic agent. The copper sulfide mineral hydrophilic agent prepared by this invention can be used as an inhibitor of copper minerals in the flotation of molybdenum ore and copper-molybdenum ore. It can effectively inhibit both primary and secondary copper minerals, and can effectively reduce the copper content in molybdenum concentrate.

[0017] (2) The copper sulfide mineral hydrophilic agent prepared by the present invention has the characteristics of low dosage and significant improvement of the hydrophilicity of copper sulfide without further adjustment of slurry potential and pH value. It does not generate hydrogen sulfide gas during use, thus overcoming the disadvantages of conventional inhibitors such as sodium sulfide / sodium hydrosulfide, which have harsh operating environment, large dosage and low efficiency.

[0018] (3) The copper sulfide mineral hydrophilic agent prepared by the present invention is easy to produce and control, has no by-products during the preparation process, and will not cause pollution to the environment during production. Attached Figure Description

[0019] Figure 1 A flowchart of the flotation test of the copper sulfide mineral hydrophilic agent prepared in Example 1 of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0022] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0023] This invention provides a method for preparing a copper sulfide mineral hydrophilic agent, comprising the following steps: S1. Add dichloroethylbenzene and sodium hypochlorite to the reactor, add sodium hydroxide to adjust the pH of the solution, and raise the temperature inside the reactor to the predetermined temperature to start the reaction.

[0024] Specifically, dichloroethylbenzene and sodium hypochlorite are added to the reactor, the pH of the solution is adjusted to 9-11 using sodium hydroxide, the power supply to the reactor is turned on to start heating, and after the temperature inside the reactor rises to 65-85℃, the reaction is carried out for 1-3 hours.

[0025] In the above steps, the mass ratio of dichloroethylbenzene to sodium hypochlorite is (1.1~1.2):1.

[0026] S2. After the reaction is complete, add thiourea to the reactor, keep the temperature inside the reactor constant, and continue the reaction.

[0027] Specifically, the mass ratio of thiourea to sodium hypochlorite in step S1 is (0.9~1.1):1, and the reaction time is 1~3h.

[0028] S3. Weigh a predetermined amount of sodium hydroxide, prepare a sodium hydroxide solution, add it to the reaction vessel, keep the temperature inside the reaction vessel constant, and cool to room temperature after the reaction is completed to obtain copper sulfide mineral hydrophilic agent.

[0029] Specifically, the mass ratio of sodium hydroxide to sodium hypochlorite in step S1 is (0.4~0.6):1, the concentration of the sodium hydroxide solution is 4~6 mol / L, and the reaction time is 1~3 h.

[0030] The copper sulfide mineral hydrophilic agent prepared by the above method was used as an inhibitor in the flotation of molybdenum ore. The flotation process steps and conditions were as follows: S1. Add -2mm molybdenum ore to a ball mill and grind until the ore content of -0.074mm is 80~85%, and adjust the slurry mass concentration to 30~35%; S2. Perform two roughing processes and four scavenging processes sequentially; for roughing process 1, the dosage of inhibitor is 100~120g / t, the dosage of kerosene is 40~50g / t, and the dosage of No. 2 oil is 20~30g / t; for roughing process 2, the dosage of inhibitor is 80~90g / t, the dosage of kerosene is 30~40g / t, and the dosage of No. 2 oil is 15~20g / t; for scavenging processes 1, 2, 3, and 4, the dosages of inhibitor are 60~70g / t, 40~50g / t, 30~40g / t, and 20~30g / t, respectively; the dosages of kerosene are 10~15g / t, 5~10g / t, 5~10g / t, and 5~10g / t, respectively; and the dosages of No. 2 oil are 10~15g / t, 5~10g / t, 5~10g / t, and 5~10g / t, respectively.

[0031] S3. After the rough concentrate is regrinded in a ball mill to a -0.045mm content of 80%~85%, it enters the beneficiation operation. The dosage of inhibitor in beneficiation 1 is 70~80g / t, and the dosage of kerosene is 5~10g / t; the dosage of inhibitor in beneficiation 2~6 is 40~50g / t, 20~30g / t, 20~30g / t, 10~15g / t, and 0g / t, respectively. The concentrate of the sixth beneficiation is molybdenum concentrate.

[0032] S4. The middlings produced by the selection and scavenging operations are returned to the previous operation in sequence to form a closed loop.

[0033] In the above steps, the molybdenum grade in the molybdenum ore is 0.03~0.25%, and the copper grade is <0.2%. Applying a copper sulfide mineral hydrophilic agent to the flotation of this type of molybdenum ore can make the copper sulfide minerals hydrophilic even with a small dosage. It has the characteristics of small dosage and high selectivity, and can achieve precise separation of copper minerals. If the copper grade exceeds 0.2%, the dosage of copper sulfide mineral hydrophilic agent will increase significantly, leading to an increase in production costs.

[0034] To more clearly demonstrate the preparation method and application effects provided by this invention, the preparation method of the copper sulfide mineral hydrophilic agent provided by this invention will be described below with reference to specific embodiments.

[0035] Example 1 Example 1 provides a method for preparing a copper sulfide mineral hydrophilic agent. A certain quartz vein type molybdenum ore is used as the research object. The molybdenum grade in the ore is 0.126%, the copper grade is 0.02%, the molybdenum sulfide content is 92.65%, and the molybdenum oxide content is 7.35%. The mineral composition and content of the ore are shown in Table 1.

[0036] Table 1 Results of mineral composition and content analysis of ore The specific preparation method includes the following steps: S1. First, weigh 120g of dichloroethylbenzene and 100g of sodium hypochlorite and add them to a small reaction vessel. Add 2.5g of sodium hydroxide to adjust the pH of the solution to 11, and turn on the power to the reaction vessel to start heating. When the temperature inside the reaction vessel rises to 75℃, start timing and react for 2 hours. S2. After the reaction is complete, weigh 100g of thiourea and add it to the reaction vessel. React at 75℃ for 1 hour. S3. Weigh 50g of sodium hydroxide and prepare a solution with a concentration of 6mol / L. Slowly add the solution to the reaction vessel and continue the reaction at 75℃ for 1.5h. After the reaction is completed, the solution is slowly cooled to obtain a copper sulfide mineral hydrophilic agent.

[0037] The obtained product will be used as an inhibitor, according to... Figure 1 The flotation test was conducted using the process shown in the diagram. S1. Add -2mm molybdenum ore to a ball mill and grind until the ore content of -0.074mm is 80%, then adjust the slurry concentration to 30%. S2. Perform two roughing processes and four scavenging processes sequentially; the dosage of inhibitor in roughing process 1 is 100 g / t, the dosage of kerosene is 40 g / t, and the dosage of No. 2 oil is 20 g / t; the dosage of inhibitor in roughing process 2 is 80 g / t, the dosage of kerosene is 30 g / t, and the dosage of No. 2 oil is 15 g / t; the dosages of inhibitor in scavenging processes 1, 2, 3, and 4 are 60 g / t, 40 g / t, 30 g / t, and 20 g / t, respectively, the dosages of kerosene are 10 g / t, 5 g / t, 5 g / t, and 5 g / t, respectively, and the dosages of No. 2 oil are 10 g / t, 5 g / t, 5 g / t, and 5 g / t, respectively.

[0038] S3. After the rough concentrate is regrinded in a ball mill to a content of 85% in -0.045mm, it enters the cleaning operation. The amount of inhibitor used in cleaning operation 1 is 80g / t, and the amount of kerosene used is 5g / t. The amounts of inhibitor used in cleaning operations 2 to 6 are 40g / t, 20g / t, 20g / t, 10g / t, and 0g / t, respectively. The concentrate from the sixth cleaning operation is molybdenum concentrate.

[0039] S4. The middlings produced by the selection and scavenging operations are returned to the previous operation in sequence to form a closed loop.

[0040] The test results are shown in Table 2.

[0041] Table 2. Flotation test results using copper sulfide mineral hydrophilic agents As shown in Table 2, when the copper sulfide mineral hydrophilic agent prepared by this invention is used for the flotation of molybdenum ore, a molybdenum concentrate with a grade of 46.86% and a copper content of 0.43% can be obtained under the condition of a total dosage of 500 g / t, and the molybdenum flotation recovery rate is 86.70%.

[0042] Comparative Example 1 Comparative Example 1 used the same molybdenum ore as Example 1, and the flotation test process and reagent dosage were the same. The difference was that Comparative Example 1 used sodium hydrosulfide as an inhibitor. The test results are shown in Table 3.

[0043] Table 3. Flotation test results using sodium hydrosulfide as an inhibitor (500 g / t) Comparative Example 2 Comparative Example 2 used the same molybdenum ore as Example 1 as the research object. The flotation test process structure and kerosene dosage were the same. The difference was that Comparative Example 2 used sodium hydrosulfide as an inhibitor. The dosage of sodium hydrosulfide inhibitor was 3 times that of the copper sulfide mineral hydrophilic agent in Example 1, that is, the total dosage was 1500 g / t. The test results are shown in Table 4.

[0044] Table 4. Flotation test results using sodium hydrosulfide as an inhibitor (1500 g / t) As shown in Table 3, when conventional sodium hydrosulfide was used as an inhibitor for molybdenum ore flotation, under the same total dosage as in Example 1, the molybdenum grade of the molybdenum concentrate was 43.63%, the copper content was 1.26%, and the molybdenum flotation recovery rate was 86.01%.

[0045] As shown in Table 4, when conventional sodium hydrosulfide was used as an inhibitor for molybdenum ore flotation, with a total dosage three times that of Example 1, the molybdenum grade of the molybdenum concentrate was 45.26%, the copper content was 0.64%, and the molybdenum flotation recovery rate was 85.86%.

[0046] A comparison of the experimental results obtained from Example 1 and Comparative Examples 1 and 2 shows that the copper sulfide mineral hydrophilic agent prepared by the method of this invention, acting as an inhibitor, can yield molybdenum concentrate with a molybdenum grade greater than 45% and a copper content of less than 0.5% at a dosage of 500 g / t. However, when sodium hydrosulfide is used as an inhibitor, with a dosage three times that of the copper sulfide hydrophilic agent, the copper content in the molybdenum concentrate remains at 0.64%. This is because the copper sulfide mineral hydrophilic agent prepared by this invention is an organic compound, which is stable and not easily oxidized, while sodium hydrosulfide is easily oxidized and degraded, resulting in a larger dosage required to achieve a certain effect. Therefore, the reagent of this invention has an ideal effect on copper sulfide minerals, inducing hydrophilicity in copper sulfide minerals with a small dosage, exhibiting the characteristics of small dosage and high selectivity, enabling precise separation of copper minerals.

[0047] In summary, the copper sulfide mineral hydrophilic agent prepared by this invention can effectively inhibit both primary and secondary copper minerals, and can reduce the copper content in molybdenum concentrate when used in molybdenum ore flotation. It also has the advantages of low dosage, no need for further adjustment of pulp potential and pH value to significantly improve the hydrophilicity of copper sulfide, convenient production control, no by-products in the preparation process, and no environmental pollution during production. The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a copper sulfide mineral hydrophilic agent, characterized in that, Includes the following steps: S1. Add dichloroethylbenzene and sodium hypochlorite to the reactor, add sodium hydroxide to adjust the pH of the solution, raise the temperature inside the reactor to the predetermined temperature, and start the reaction time. S2. After the reaction is complete, add thiourea to the reactor, keep the temperature inside the reactor constant, and continue the reaction; S3. Weigh a predetermined amount of sodium hydroxide, prepare a sodium hydroxide solution, add it to the reaction vessel, keep the temperature inside the reaction vessel constant, and cool to room temperature after the reaction is completed to obtain copper sulfide mineral hydrophilic agent.

2. The method for preparing the copper sulfide mineral hydrophilic agent according to claim 1, characterized in that, In step S1, the mass ratio of dichloroethylbenzene to sodium hypochlorite is (1.1-1.2):

1.

3. The method for preparing the copper sulfide mineral hydrophilic agent according to claim 1, characterized in that, In step S1, the pH of the solution is adjusted to 9-11.

4. The method for preparing the copper sulfide mineral hydrophilic agent according to claim 1, characterized in that, In step S1, the predetermined temperature is 65-85°C, and the reaction time is 1-3 hours.

5. The method for preparing the copper sulfide mineral hydrophilic agent according to claim 1, characterized in that, In step S2, the mass ratio of the thiourea to the sodium hypochlorite in step S1 is (0.9-1.1):1, and the reaction time is 1-3 hours.

6. The method for preparing the copper sulfide mineral hydrophilic agent according to claim 1, characterized in that, In step S3, the mass ratio of sodium hydroxide to sodium hypochlorite in step S1 is (0.4-0.6):1, the concentration of the sodium hydroxide solution is 4-6 mol / L, and the reaction time is 1-3 h.

7. A copper sulfide mineral hydrophilic agent, characterized in that, The copper sulfide mineral hydrophilic agent is prepared by the method described in any one of claims 1-6.

8. A method for applying the copper sulfide mineral hydrophilic agent according to claim 7, characterized in that, The application of the copper sulfide mineral hydrophilic agent as a depressant in the flotation of molybdenum ore includes the following steps: S1. Add -2mm molybdenum ore to a ball mill and grind until the ore content of -0.074mm is 80% to 85%, and adjust the slurry mass concentration to 30% to 35%; S2. Perform two coarse selections and four sweep selections in sequence; S3. After the rough concentrate is regrinded in a ball mill to a content of 80% to 85% in -0.045mm, it enters a sixth cleaning operation. The concentrate from the sixth cleaning operation is molybdenum concentrate. S4. The middlings produced by the selection and scavenging operations are returned to the previous operation in sequence to form a closed loop.

9. The method of applying the copper sulfide mineral hydrophilic agent according to claim 8, characterized in that, The molybdenum ore contains 0.03–0.25% molybdenum and <0.2% copper.

10. The method of applying the copper sulfide mineral hydrophilic agent according to claim 8, characterized in that, In step S2, the amount of inhibitor used in the coarse selection is 80-120 g / t, and the amount of inhibitor used in the scavenging selection is 20-70 g / t; in step S3, the amount of inhibitor used in the fine selection is 0-80 g / t.

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