Combined modifier for copper oxide mineral flotation and application thereof

Abstract

The present application relates to a kind of copper oxide mineral flotation combination regulator, the combination regulator is composed of imidazole hydroxide, sodium sulfide and sodium sulfite;The imidazole hydroxide refers to the ionic liquid that cation is 1-butyl-3-methylimidazole, anion is hydroxyl group. Meanwhile, the application of the combination regulator is also disclosed, which is used in the sulfidation process of copper oxide ore sulfidation flotation or in the process of copper oxide concentrate selection process.The present application has the characteristics of high copper recovery, good index stability, strong process operability and wide application range.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, and in particular to a combined modifier for the flotation of copper oxide minerals and its application. Background Technology

[0002] Compared to copper sulfide minerals, copper oxide minerals have more complex compositions, ore structures, and textures, resulting in poorer processing properties. Sulfide flotation is the main method for processing copper oxide ores in China. Specifically, the copper oxide ores are first pre-sulfided with a sulfiding agent, and then flotation is performed using a sulfide ore collector.

[0003] The commonly used sulfiding agents for copper oxide minerals are sodium sulfide or sodium hydrosulfide. However, both sodium sulfide and sodium hydrosulfide are chemically unstable and are easily oxidized and rendered ineffective in the pulp. They are also prone to a decrease in the content of useful ions due to a drop in the pH value of the pulp. Therefore, in practical applications of sulfidation flotation, there are often disadvantages such as large dosage of sodium sulfide, poor process stability, and poor flotation effect. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a combined modifier for the flotation of copper oxide minerals with high copper recovery rate, good index stability, strong process operability, and wide applicability.

[0005] Another technical problem to be solved by the present invention is to provide the application of the combined modifier for the flotation of copper oxide minerals.

[0006] To solve the above problems, the present invention provides a combined modifier for the flotation of copper oxide minerals, characterized in that: the combined modifier is composed of imidazole hydroxide, sodium sulfide and sodium sulfite; wherein the imidazole hydroxide refers to an ionic liquid with 1-butyl-3-methylimidazolium as the cation and hydroxide as the anion.

[0007] The application of the combined modifier for the flotation of copper oxide minerals as described above is characterized in that: the combined modifier is used in the sulfidation process of copper oxide mineral sulfidation flotation or in the beneficiation process of copper oxide concentrate.

[0008] In the sulfidation process or copper oxide concentrate beneficiation process, imidazole hydroxide is first added to the slurry, followed by the simultaneous addition of sodium sulfide and sodium sulfite.

[0009] The amount of imidazole hydroxide added is added in stages according to the pH of the slurry, and the pH of the slurry is always maintained at 9~10.

[0010] The total amount of sodium sulfide and sodium sulfite added during the sulfidation process is 1200~2400g / t based on the mass of the slurry, and the mass ratio of sodium sulfide to sodium sulfite is 1:1.

[0011] The total amount of sodium sulfide and sodium sulfite added during the copper oxide concentrate beneficiation process is 200~400g / t based on the slurry mass, and the mass ratio of sodium sulfide to sodium sulfite is 1:1.

[0012] Compared with the prior art, the present invention has the following advantages: 1. This invention uses a novel organic agent, 1-butyl-3-methylimidazole hydroxide, as a pulp pH adjuster to maintain the pulp pH value, thereby reducing the hydrolysis reaction of sodium sulfide and increasing the concentration of sulfide ions in the pulp. On the other hand, unlike conventional inorganic pH adjusters such as lime and sodium carbonate, this agent contains an imidazole group in its cation, which can be adsorbed on the mineral surface to enhance the subsequent collection of copper oxide minerals by xanthate.

[0013] 2. The addition of sodium sulfite in this invention gives it strong reducing properties during the sulfidation process, which can reduce the oxidation of sodium sulfide by dissolved oxygen in the slurry, increase the effective concentration of sodium sulfide, enhance the sulfidation effect, and effectively solve the problems of unstable sodium sulfide properties, large reagent dosage, and low flotation index during copper oxide sulfidation flotation.

[0014] 3. The combination modifier of the present invention has the characteristics of high copper recovery rate, good index stability, strong process operability and wide applicability. Detailed Implementation

[0015] A combined modifier for the flotation of copper oxide minerals, comprising imidazole hydroxide, sodium sulfide, and sodium sulfite; imidazole hydroxide refers to an ionic liquid with 1-butyl-3-methylimidazolium as the cation and hydroxide as the anion.

[0016] This paper describes the application of a combined modifier in the flotation of copper monoxide minerals. This modifier is used in the sulfidation process of copper monoxide ore sulfidation flotation or in the beneficiation process of copper monoxide concentrate. Specifically, during the sulfidation process or beneficiation process, imidazole hydroxide is first added to the pulp, followed by the simultaneous addition of sodium sulfide and sodium sulfite. The amount of imidazole hydroxide added is staged according to the pulp pH, maintaining the pulp pH at 9-10. During the sulfidation process, the total amount of sodium sulfide and sodium sulfite added is 1200-2400 g / t based on the pulp mass, with a sodium sulfide to sodium sulfite mass ratio (g / g) of 1:1. During the beneficiation process of copper monoxide concentrate, the total amount of sodium sulfide and sodium sulfite added is 200-400 g / t based on the pulp mass, with a sodium sulfide to sodium sulfite mass ratio (g / g) of 1:1.

[0017] The specific application process is as follows: 1) Grinding: After crushing the raw ore, wet grind it to a fineness of -0.074mm, accounting for 60%~70%, with a grinding concentration of 55%; 2) Desliming of grinding products: The grinding products obtained in step 1) are subjected to sedimentation and desliming to remove the ore slime with a particle size <0.01mm, resulting in ore slime products and non-slime products; 3) Mineral sulfidation: After adjusting the concentration of the non-mud product obtained in step 2) to 34%, first add 1-butyl-3-methylimidazolium hydroxide to adjust the pH of the slurry to 9-10; then add 1200-2400 g / t of a mixture of sodium sulfide and sodium sulfite with a mass ratio (g / g) of 1:1, and stir for 5 min to obtain sulfided slurry; 4) Flotation: The sulfide slurry obtained in step 3) is subjected to roughing, cleaning, and scavenging to obtain copper oxide concentrate and tailings. That is: Add 150-250 g / t of collector butyl xanthate and 2 g / t of frother to the sulfide slurry obtained in step 3). # 40-80 g / t of oil is used for roughing of copper oxide minerals to obtain rough concentrate and rough tailings. The rough concentrate is then adjusted to a pulp concentration of 10%-20%. First, 1-butyl-3-methylimidazolium hydroxide is added to adjust the pulp pH to 9-10. Then, 200-400 g / t of a mixture of sodium sulfide and sodium sulfite at a mass ratio of 1:1 is added for copper oxide concentrate cleaning. After three cleaning processes, copper oxide concentrate and middlings from each cleaning process are obtained. The rough tailings are adjusted to a pulp concentration of 25%-30%. 20-30 g / t of sodium sulfide activator, 10-30 g / t of butyl xanthate collector, and 5-10 g / t of frother are added for copper oxide mineral scavenging. After one scavenging process, copper oxide scavenged middlings and tailings are obtained. The middlings from each cleaning process and the scavenged middlings are returned to the previous flotation operation.

[0018] 1-Butyl-3-methylimidazole hydroxide, CAS No.: 528818-81-7.

[0019] Example 1 The test ore sample was from a copper oxide mine in Gansu Province. The original ore had a copper grade of 1.11%, and the main copper minerals were azurite and malachite, with small amounts of cuprite and copper sulfide. The following flotation process and conditions were used to recover copper oxide from this ore: 1) Grinding: Crush 1 kg of raw ore and wet grind it to a fineness of -0.074 mm, accounting for 60%, with a grinding concentration of 55%; 2) Desliming of grinding products: The grinding products obtained in step 1) are subjected to sedimentation and desliming to remove the ore slime with a particle size <0.01mm, resulting in ore slime products and non-slime products; 3) Mineral sulfidation: After adjusting the non-mud product obtained in step 2) to a concentration of 34%, first add 120 g / t of 1-butyl-3-methylimidazolium hydroxide (slurry pH=9~10), then add 1000 g / t of a mixture of sodium sulfide and sodium sulfite in a mass ratio of 1:1, stir for 5 min to obtain sulfided slurry; 4) Flotation: Add 200g / t of collector butyl xanthate and 2g / t of frother to the sulfide slurry obtained in step 3). # 60 g / t of oil is used for roughing of copper oxide minerals to obtain rough concentrate and rough tailings. The rough concentrate is then adjusted to a pulp concentration of 15%, and 20 g / t of 1-butyl-3-methylimidazolium hydroxide (pulp pH=9~10) is added. Then, 300 g / t of a mixture of sodium sulfide and sodium sulfite in a 1:1 mass ratio is added for copper oxide concentrate cleaning. After three cleaning processes, copper oxide concentrate and middlings from each cleaning process are obtained. The rough tailings are adjusted to a pulp concentration of 28%, and 25 g / t of sodium sulfide activator, 20 g / t of butyl xanthate collector, and 5 g / t of frother are added for copper oxide mineral scavenging. After one scavenging process, copper oxide scavenged middlings and tailings are obtained. The middlings from each cleaning process and the scavenged middlings are returned to the previous flotation operation.

[0020] The comparison of the test indicators obtained using the above reagents and processes with those obtained using sodium sulfide as a modifier under the same process conditions is shown in Table 1 below. As can be seen from the table, under the same process conditions, the copper recovery rate can be increased by approximately 7% using the modifier described in this invention compared to the conventional modifier sodium sulfide.

[0021] Table 1 Comparison of test indicators in Example 1 Example 2 The test ore sample was a copper oxide ore with high slime content and a copper grade of 0.92%. The copper minerals in the ore were mainly chrysocolla, malachite, and cuprite, belonging to a low-grade and difficult-to-process copper oxide ore.

[0022] The copper oxide recovery process is as follows: 1) Grinding: After crushing 1 kg of raw ore, wet grind it to a fineness of -0.074 mm, accounting for 65%, with a grinding concentration of 55%; 2) Desliming of grinding products: The grinding products obtained in step 1) are subjected to sedimentation and desliming to remove the ore slime with a particle size <0.01mm, resulting in ore slime products and non-slime products; 3) Mineral sulfidation: After adjusting the non-mud product obtained in step 2) to a concentration of 34%, add 150 g / t of 1-butyl-3-methylimidazolium hydroxide (slurry pH=9~10), add 1500 g / t of a mixture of sodium sulfide and sodium sulfite in a mass ratio of 1:1, stir for 5 min to obtain sulfided slurry; 4) Flotation: Add 150g / t of collector butyl xanthate and 2g of frother to the sulfide slurry prepared in step 3) sequentially. #40 g / t of oil is used for roughing of copper oxide minerals to obtain rough concentrate and rough tailings. The rough concentrate is then adjusted to a pulp concentration of 10%, and 20 g / t of 1-butyl-3-methylimidazolium hydroxide (pulp pH=9~10) is added. Then, 200 g / t of a mixture of sodium sulfide and sodium sulfite at a mass ratio of 1:1 is added for copper oxide concentrate cleaning. After three cleaning processes, copper oxide concentrate and middlings from each cleaning process are obtained. The rough tailings are adjusted to a pulp concentration of 30%, and 20 g / t of sodium sulfide activator, 10 g / t of butyl xanthate collector, and 5 g / t of frother are added for copper oxide mineral scavenging. After one scavenging process, copper oxide scavenged middlings and tailings are obtained. The middlings from each cleaning process and the scavenged middlings are returned to the previous flotation operation.

[0023] The comparison of the test indicators obtained using the above reagents and processes with those obtained using sodium sulfide as a modifier under the same process conditions is shown in Table 2 below. As can be seen from the table, under the same process conditions, the copper recovery rate can be increased by approximately 11% using the modifier described in this invention compared to the conventional modifier sodium sulfide.

[0024] Table 2 Comparison of test indicators in Example 2 Example 3 The test ore sample was from a copper oxide mine in Jiangxi Province, with a copper grade of 2.36%. The copper minerals were mainly malachite and azurite, with a small amount of chalcopyrite and native copper.

[0025] The copper oxide recovery process is as follows: 1) Grinding: Crush 1 kg of raw ore and wet grind it to a fineness of -0.074 mm, accounting for 70%, with a grinding concentration of 55%; 2) Desliming of grinding products: The grinding products obtained in step 1) are subjected to sedimentation and desliming to remove the ore slime with a particle size <0.01mm, resulting in ore slime products and non-slime products; 3) Mineral sulfidation: After adjusting the non-mud product obtained in step 2) to a concentration of 34%, add 100 g / t of 1-butyl-3-methylimidazolium hydroxide (slurry pH=9~10), add 2000 g / t of a mixture of sodium sulfide and sodium sulfite in a mass ratio of 1:1, stir for 5 min to obtain sulfided slurry; 4) Flotation: Add 250g / t of collector butyl xanthate and 2g / t of frother to the sulfide slurry obtained in step 3). #80 g / t of oil is used for roughing of copper oxide minerals to obtain rough concentrate and rough tailings. The rough concentrate is adjusted to a pulp concentration of 20%, and 15 g / t of 1-butyl-3-methylimidazolium hydroxide (pulp pH=9~10) is added. Then, 400 g / t of a mixture of sodium sulfide and sodium sulfite in a 1:1 mass ratio is added for copper oxide concentrate cleaning. After three cleaning processes, copper oxide concentrate and middlings from each cleaning process are obtained. The rough tailings are adjusted to a pulp concentration of 25%, and 30 g / t of sodium sulfide activator, 30 g / t of butyl xanthate collector, and 10 g / t of frother are added for copper oxide mineral scavenging. After one scavenging process, copper oxide scavenged middlings and tailings are obtained. The middlings from each cleaning process and the scavenged middlings are returned to the previous flotation operation.

[0026] The comparison of the test indicators obtained using the above reagents and processes with those obtained using sodium sulfide as a modifier under the same process conditions is shown in Table 3 below. As can be seen from the table, under the same process conditions, the copper recovery rate can be increased by approximately 9% using the modifier described in this invention compared to the conventional modifier sodium sulfide.

[0027] Table 3 Comparison of test indicators in Example 3

Claims

1. The application of a combined modifier for the flotation of copper oxide minerals, characterized in that: The combined modifier consists of imidazole hydroxide, sodium sulfide, and sodium sulfite; the imidazole hydroxide refers to an ionic liquid with 1-butyl-3-methylimidazolium as the cation and hydroxide as the anion; the combined modifier is used in the sulfidation process of copper oxide ore sulfidation flotation or in the copper oxide concentrate beneficiation process; in the sulfidation process or copper oxide concentrate beneficiation process, imidazole hydroxide is first added to the slurry, and then sodium sulfide and sodium sulfite are added simultaneously.

2. The application of the combined modifier for copper oxide mineral flotation as described in claim 1, characterized in that: The amount of imidazole hydroxide added is added in stages according to the pH of the slurry, and the pH of the slurry is always maintained at 9~10.

3. The application of the combined modifier for copper oxide mineral flotation as described in claim 1, characterized in that: The total amount of sodium sulfide and sodium sulfite added during the sulfidation process is 1200~2400g / t based on the mass of the slurry, and the mass ratio of sodium sulfide to sodium sulfite is 1:

1.

4. The application of the combined modifier for copper oxide mineral flotation as described in claim 1, characterized in that: The total amount of sodium sulfide and sodium sulfite added during the copper oxide concentrate beneficiation process is 200~400g / t based on the slurry mass, and the mass ratio of sodium sulfide to sodium sulfite is 1:1.

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