A method for separating copper and molybdenum in copper-molybdenum concentrate

Abstract

The application discloses a method for separating copper and molybdenum in copper-molybdenum concentrate, which uses water as leaching reagent and adds leaching aids in the water to replace the mixing of acid and molybdenum concentrate; in the pre-leaching process, auxiliary ultrasonic high-frequency oscillation is used to promote the disembedding of copper and molybdenum particles and accelerate the dispersion of the particles; then, oxygen pressure cooking is carried out in cooperation with the temperature and oxygen partial pressure, so that the accurate and efficient separation of molybdenum and copper is realized; after the leaching residue is dried, the molybdenum concentrate with copper content meeting the national standard requirements is obtained, and the copper in the liquid is recovered by using a suitable method. In the application, the copper is only leached into the solution under the conditions of low temperature, short time and low pressure, the leaching of molybdenum is limited, and the molybdenum can continue to be in the form of original molybdenum concentrate in the residue. In addition, the method of the application uses water pre-leaching, and the copper is leached into the solution under the assistance of ultrasonic and leaching aids, and the copper content of the treated molybdenum concentrate is less than 0.15%.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, specifically to a method for separating copper and molybdenum in copper-molybdenum concentrate. Background Technology

[0002] Molybdenum, an important rare refractory metal, is used in the steel industry (over 80%), with the remainder used in molybdenum chemicals and other metals. In recent years, the domestic production capacity of copper-containing molybdenum concentrate has been increasing, accounting for approximately 20% of the total molybdenum concentrate production. Due to beneficiation technology and cost considerations, the copper content in copper-containing molybdenum concentrate products is mostly between 1.5% and 10%. Standard molybdenum concentrate is mainly produced by oxidative roasting in multi-hearth furnaces and energy-saving rotary kilns to produce molybdenum oxide (molybdenum roasted sand), high-soluble molybdenum oxide to produce ammonium molybdate, and industrial molybdenum oxide to produce ferromolybdenum. During the roasting process, copper oxide and molybdenum trioxide in copper-containing molybdenum concentrate easily form low-melting-point eutectics, causing the material to melt and agglomerate, severely impacting the converter's capacity; the higher the copper content, the greater the impact.

[0003] Copper-molybdenum concentrate is mainly processed and applied in the following two ways: 1. Batching roasting: To solve the problem of agglomeration during roasting of copper-molybdenum concentrate, roasting enterprises often adopt batch roasting (mixing copper-molybdenum concentrate with low-copper-molybdenum concentrate for roasting). The resulting molybdenum roasted ore has high sulfur and copper content, which cannot meet the quality requirements of molybdenum roasted ore for ferromolybdenum production; when used in ammonium molybdate production, its high ammonia-insoluble molybdenum content affects the recovery rate of ammonium molybdate. 2. Chlorination leaching method: The copper in the molybdenum concentrate is oxidized and leached out by a mixed solution of chloride salt and hydrochloric acid to obtain molybdenum concentrate that meets the requirements of the roasting process. Although this method can meet the production requirements of ferromolybdenum, it causes severe corrosion to the equipment itself and affects the yield of molybdenum roasted ore produced by subsequent roasting and the service life of the roasting equipment.

[0004] To address the aforementioned issues, the industry employs oxygen-pressure acid leaching to separate copper and molybdenum. Chinese patent application CN114686684A discloses a method for recovering metallic elements from molybdenum concentrate, which involves leaching at a temperature of 180-210℃, an oxygen pressure of 0.8-1.5 MPa, a leaching time of 2-5 hours, and using a leaching aid (one or a combination of phosphoric acid and calcium phosphate) at a concentration of 0.5 to 1.5 times the mass of the molybdenum concentrate, thereby completely leaching molybdenum, copper, and rhenium into the solution.

[0005] Chinese patent application CN101469375A discloses a method for removing copper impurities from molybdenum concentrate. The method uses 50% concentrated sulfuric acid of the total amount of molybdenum concentrate, which is added to the molybdenum concentrate in three steps. The leaching solution is heated to 160-200℃ and leached for 2-6 hours. The leached molybdenum concentrate is then washed with water several times. The copper content of the treated molybdenum concentrate is less than 0.5%.

[0006] Chinese patent application CN104846216A discloses a method for processing complex copper-molybdenum concentrate. The method involves finely grinding the molybdenum concentrate and then leaching it with one or more acids, such as sulfuric acid, nitric acid, or hydrochloric acid, or a mixture thereof. The reaction temperature is 80-200℃, the oxygen partial pressure is 2-10 standard atmospheres, and one or more of the following are used as leaching aids: coal powder, coke, and activated carbon. The reaction time is 0.5-5 hours to achieve copper-molybdenum separation.

[0007] Copper and molybdenum exist in distinct forms in copper-molybdenum concentrates, yet they are intercalated. While oxy-pressure acid leaching can leach copper into the solution, the addition of acid promotes the oxidation of the molybdenum concentrate, generating significant amounts of molybdenum oxide, some of which enters the solution as molybdates. The unstable copper and molybdenum content in the raw copper-molybdenum concentrate makes process control, such as acid dosage and ratio, difficult. The use of acid in these methods increases material costs, environmental and safety costs in subsequent treatment, and causes greater equipment corrosion. Furthermore, the separation and recovery of molybdenum and copper in the liquid phase in a high-acidity solution is costly. The low-cost separation of copper and molybdenum from copper-molybdenum concentrates and the limited application areas have long hindered the industry's development. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention aims to provide a method for separating copper and molybdenum in copper-molybdenum concentrate.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A method for separating copper and molybdenum in copper-molybdenum concentrate includes the following steps:

[0011] S1. Mix copper-molybdenum concentrate, water and leaching aid for slurry pre-leaching, and simultaneously use ultrasonic high-frequency oscillation during the pre-leaching process; the leaching aid is one or more of polyethylene glycol, glycerol and stearic acid.

[0012] S2. The prepreg solution obtained in step S1 is fed into a pressure reactor and reacted for 0.5-2 hours at a temperature of 145-165℃ and an oxygen partial pressure of 0.4-0.8 MPa.

[0013] S3. Filter the slurry obtained after the reaction in step S2.

[0014] S4. The leaching residue obtained from the filtration in step S3 is washed and dried to obtain the copper-separated molybdenum concentrate. The leaching solution obtained from the filtration is used for copper recovery.

[0015] Further, in step S1, the copper-molybdenum concentrate has a particle size that passes through an 80-400 mesh sieve and a copper mass content of 1.5-10%.

[0016] Further, in step S1, the amount of the leaching aid is 0.1%-0.625% of the mass of water.

[0017] Further, in step S1, the solid-liquid ratio of the copper-molybdenum concentrate and water is 1:3-5 (g / ml), the ultrasonic oscillation frequency is 400-800W, and the pre-soaking time is 1-2h.

[0018] Furthermore, in step S3, the filter mesh size is 1500-3000 mesh.

[0019] Furthermore, in step S3, the leaching solution obtained by filtration is subjected to copper sulfide deposition.

[0020] Furthermore, the copper content of the molybdenum concentrate obtained in step S4 is less than 0.15%.

[0021] The beneficial effects of this invention are as follows: This invention uses water as a leaching reagent and adds leaching aids to it to replace acid in mixing with molybdenum concentrate; during the pre-leaching process, ultrasonic high-frequency oscillation is used to promote the deintercalation of molybdenum and copper particles and accelerate particle dispersion; then, oxygen pressure boiling is carried out with appropriate temperature and oxygen partial pressure to achieve precise and efficient separation of molybdenum and copper. After drying the leaching residue, a molybdenum concentrate that meets the requirements is obtained, and copper in the liquid is recovered by appropriate methods.

[0022] Specifically, this invention leaches only copper into the solution under low temperature, short time, and low pressure conditions, limiting the leaching of molybdenum, which can remain in the slag as the original molybdenum concentrate. Furthermore, the method of this invention uses water pre-leaching, and copper is leached into the solution with the assistance of ultrasound and a leaching aid. The treated molybdenum concentrate contains less than 0.15% copper. Detailed Implementation

[0023] The present invention will be further described below. It should be noted that this embodiment is based on the present technical solution and provides detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to this embodiment.

[0024] Example 1

[0025] Take 200g of copper-molybdenum concentrate, the main components of which are 40.32% molybdenum and 2.7% copper. The copper concentrate is 100% sieved through an 80-mesh sieve. Add 1000ml of pure water for pre-impregnation, add 1g of polyethylene glycol, and ultrasonically vibrate in a pre-impregnation tank at 800W power for 2 hours. Pour the pre-impregnation solution into a pressure reactor, introduce oxygen, and react for 2 hours at 145℃ and an oxygen partial pressure of 0.8MPa.

[0026] After the reaction, the material was filtered through a 1500-mesh sieve, yielding 177.89 grams of dry residue. Analysis showed that the Cu content in the residue was 0.13 wt%. Analysis of the filtrate revealed a molybdenum content of 15 mg / L, resulting in a molybdenum recovery rate of 99.9%. The filtrate was then subjected to copper sulfide precipitation to obtain solid copper sulfide with a copper content of 54.5%.

[0027] Example 2

[0028] Take 200g of copper-molybdenum concentrate, with main components of 38.32% molybdenum and 5.7% copper. 100% of the copper concentrate must pass through a 200-mesh sieve. Add 800ml of pure water for pre-impregnation, then add 3g of polyethylene glycol. In a pre-impregnation tank, use an ultrasonic probe to perform ultrasonic oscillation at 600W power for 1 hour. Pour the pre-impregnation solution into a pressure reactor, introduce oxygen, and react for 1 hour at 150℃ and an oxygen partial pressure of 0.6 MPa.

[0029] After the reaction, the material was filtered through a 3000-mesh sieve, yielding 167.58 grams of dry residue. Analysis showed that the Cu content in the residue was 0.09 wt%. Analysis of the filtrate revealed a molybdenum content of 35 mg / L, resulting in a molybdenum recovery rate of 99.82%. The filtrate was then subjected to copper sulfide precipitation to obtain solid copper sulfide with a copper content of 50.5%.

[0030] Example 3

[0031] Take 200g of copper-molybdenum concentrate, with main components of 34.32% molybdenum and 9.8% copper. 100% of the copper concentrate must pass through a 400-mesh sieve. Add 800ml of pure water for pre-impregnation, and add 5g of a mixture of polyethylene glycol and stearic acid in a 1:1 ratio. Perform ultrasonic oscillation at 400W for 1 hour in a pre-impregnation tank using an ultrasonic probe. Pour the pre-impregnation solution into a pressure reactor, introduce oxygen, and react for 0.5 hours at 165℃ and an oxygen partial pressure of 0.4 MPa.

[0032] After the reaction, the material was filtered through a 1500-mesh sieve, yielding 156.8 grams of dry residue. Analysis showed that the Cu content in the residue was 0.11 wt%. Analysis of the filtrate revealed a molybdenum content of 165 mg / L, resulting in a molybdenum recovery rate of 99.03%. The filtrate was then subjected to copper sulfide precipitation to obtain solid copper sulfide with a copper content of 53.5%.

[0033] Example 4

[0034] Take 200g of copper-molybdenum concentrate, with main components of 45.32% molybdenum and 1.5% copper. 100% of the copper concentrate must pass through a 400-mesh sieve. Add 600ml of pure water for pre-impregnation, then add 1g of polyethylene glycol. In a pre-impregnation tank, use an ultrasonic probe to perform ultrasonic oscillation at 400W power for 1 hour. Pour the pre-impregnation solution into a pressure reactor, introduce oxygen, and react for 1 hour at 150℃ and an oxygen partial pressure of 0.6MPa.

[0035] After the reaction, the material was filtered through a 2000-mesh sieve, yielding 187.46 grams of dry residue. Analysis showed that the Cu content in the residue was 0.06 wt%. Analysis of the filtrate revealed a molybdenum content of 28 mg / L, resulting in a molybdenum recovery rate of 99.9%. The filtrate was then subjected to copper sulfide precipitation to obtain solid copper sulfide with a copper content of 58.5%.

[0036] Example 5

[0037] Take 200g of copper-molybdenum concentrate, the main components of which are 42.32% molybdenum and 3% copper, and 100% of the copper concentrate has passed through an 80-mesh sieve. Add 600ml of pure water for pre-impregnation and 2g of glycerol. In a pre-impregnation tank, use an ultrasonic probe to perform ultrasonic oscillation at 500W power for 1.5 hours. Pour the pre-impregnation solution into a pressure reactor, introduce oxygen, and react for 1 hour at a temperature of 150℃ and an oxygen partial pressure of 0.6MPa.

[0038] After the reaction, the material was filtered through a 2000-mesh sieve, yielding 184.46 grams of dry residue. Analysis showed that the Cu content in the residue was 0.12 wt%. Analysis of the filtrate revealed a molybdenum content of 160 mg / L, resulting in a molybdenum recovery rate of 99.88%. The filtrate was then subjected to copper sulfide precipitation to obtain solid copper sulfide with a copper content of 54.5%.

[0039] For those skilled in the art, various corresponding changes and modifications can be made based on the above technical solutions and concepts, and all such changes and modifications should be included within the protection scope of the claims of this invention.

Claims

1. A method for separating copper and molybdenum in copper-molybdenum concentrate, characterized in that, Includes the following steps: S1. Mix copper-molybdenum concentrate, water and leaching aid for slurry pre-leaching, and simultaneously use ultrasonic high-frequency oscillation during the pre-leaching process; the leaching aid is one or more of polyethylene glycol, glycerol and stearic acid. S2. The prepreg solution obtained in step S1 is fed into a pressure reactor and reacted for 0.5-2 hours at a temperature of 145-165℃ and an oxygen partial pressure of 0.4-0.8 MPa. S3. Filter the slurry obtained after the reaction in step S2. S4. The leaching residue obtained from the filtration in step S3 is washed and dried to obtain the copper-separated molybdenum concentrate. The leaching solution obtained from the filtration is used for copper recovery.

2. The method according to claim 1, characterized in that, In step S1, the copper-molybdenum concentrate has a particle size that passes through an 80-400 mesh sieve and a copper mass content of 1.5-10%.

3. The method according to claim 1, characterized in that, In step S1, the amount of the leaching aid is 0.1%-0.625% of the mass of water.

4. The method according to claim 1, characterized in that, In step S1, the solid-liquid ratio of the copper-molybdenum concentrate and water is 1:3-5 (g / ml), the ultrasonic oscillation frequency is 400-800W, and the pre-soaking time is 1-2h.

5. The method according to claim 1, characterized in that, In step S3, the filter mesh size is 1500-3000 mesh.

6. The method according to claim 1, characterized in that, In step S3, the leaching solution obtained by filtration is subjected to copper sulfide deposition.

7. The method according to claim 1, characterized in that, The copper content of the molybdenum concentrate obtained in step S4 is less than 0.15%.