Inhibitor for efficiently separating copper and sulfur under low-alkalinity condition, flotation reagent and flotation method

Abstract

The invention relates to an inhibitor for efficiently separating copper and sulfur under a low-alkalinity condition, a flotation reagent and a flotation method. The inhibitor is a compound as shown in a formula I (formula I), wherein R1, R2, R3 and R4 are respectively and independently selected from one of-R5X,-X,-H and-N + R6, R5 is alkyl of C1-C10, naphthenic base of C3-C10 or heterocyclic group of C3-C10, and the ring of the heterocyclic group is provided with or not provided with a substituent group; x is one of F, Cl, Br, I, tertiary amine positive ions, nitro, cyano, sulfo, formyl, acyl and carboxyl; r6 is a C1-C5 alkyl group or a C3-C5 cycloalkyl group; the inhibitor is low in viscosity and good in fluidity, pyrite and chalcopyrite in complex copper sulfide ore copper-sulfur ore can be effectively separated under the low-alkalinity condition, and the separation effect is remarkable.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, and more specifically, to an inhibitor, flotation reagent, and flotation method for efficient separation of copper and sulfur under low alkalinity conditions. Background Technology

[0002] Among non-ferrous metal mineral resources, copper ore has significant development value, primarily in the form of copper sulfide ores. Pyrite, as the most widely distributed sulfide mineral in nature, is abundant in various sulfide deposits, typically accounting for 70%–95% of the total sulfide mineral content. Copper-sulfur (chalcopyrite-pyrite) coexistence is a common type of copper sulfide ore. Both minerals have similar crystal structures (isometric crystal system), surface properties, and similar environments for flotation reagents, making selective inhibition of pyrite difficult. Currently, the key challenge in copper-sulfur flotation separation lies in the complexity of mineral interface chemistry and the interaction between the mineral pulp environment. Traditional copper-sulfur separation processes generally employ lime to create a highly alkaline environment (pH>11) to suppress pyrite. Although this method can achieve basic separation, it has three major technical drawbacks: First, high alkalinity leads to a significant increase in slurry viscosity, causing abnormal foam stability and pipeline blockage, reducing separation efficiency; Second, pyrite passivated by strong alkali needs to be activated with strong acids such as sulfuric acid, which not only corrodes equipment and increases safety hazards, but also generates high-salt wastewater; Third, the process contradicts the advocated low-carbon and clean production requirements.

[0003] Therefore, developing new low-alkali and environmentally friendly inhibitors has become a key technological challenge in the field of copper-sulfur flotation. Summary of the Invention

[0004] Based on the aforementioned technical problems in the existing technology, the present invention provides an inhibitor for efficient separation of copper and sulfur under low alkalinity conditions. This inhibitor has low viscosity and good fluidity, and can effectively separate pyrite and chalcopyrite in complex copper sulfide ore, copper sulfide ore, under low alkalinity conditions, with significant separation effect.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] An inhibitor for efficient separation of copper and sulfur under low alkalinity conditions, wherein the inhibitor is a compound of formula I:

[0007] (Formula I);

[0008] Among them, R1, R2, R3, and R4 are each independently selected from -R5X, -X, -H, and -N. +R6 is one of the following: R5 is a C1-C10 alkyl group, a C3-C10 cycloalkyl group, or a C3-C10 heterocyclic group, wherein the heterocyclic group has or does not have substituents on its ring; X is one of F, Cl, Br, I, tertiary amine cation, nitro, cyano, sulfonic acid group, formyl group, acyl group, and carboxyl group.

[0009] R6 is a C1-C5 alkyl or C3-C5 cycloalkyl.

[0010] In some embodiments, R5 is a C1-C6 alkyl, C3-C6 cycloalkyl, C3-C6 heterocyclic, phenyl, benzyl, or benzyloxy group, wherein the aromatic ring of the phenyl, benzyl, or benzyloxy group may or may not have substituents, and the ring of the heterocyclic group may or may not have substituents.

[0011] In some embodiments, the inhibitor is at least one of the following compounds:

[0012] , , , , , , , , , ,

[0013] , .

[0014] The present invention also provides a flotation reagent for efficient separation of copper and sulfur under low alkalinity conditions. The flotation reagent includes an inhibitor, a collector, and a frother. The inhibitor is a compound having the structure of Formula I according to any of the above embodiments.

[0015] In some embodiments, the collector comprises isopropyl xanthate; the foaming agent comprises methyl isobutyl alcohol.

[0016] This invention also provides a method for efficient flotation separation of copper and sulfur under low alkalinity conditions, the method comprising the following steps:

[0017] S1. Grind the raw ore and add water to make a slurry;

[0018] S2. Add flotation reagents to the slurry and perform flotation to obtain concentrate and tailings;

[0019] The flotation reagent is any of the flotation reagents described in the above embodiments; the flotation process includes at least one roughing and one scavenging.

[0020] In some embodiments, in step S2, during the roughing process, the inhibitor, collector, and frother from the flotation reagents are added sequentially to the slurry for roughing to obtain roughing concentrate and roughing tailings; during the scavenging process, the collector is added to the roughing tailings for scavenging to obtain scavenging concentrate and scavenging tailings; the roughing concentrate is copper concentrate, and the scavenging tailings are the final tailings.

[0021] In some embodiments, during the roughing process, the amount of inhibitor added is 100-300 g / t; the amount of collector added is 7-25 g / t; the amount of frother added is 1-10 g / t; and during the scavenging process, the amount of collector added is 5-15 g / t.

[0022] In some implementations, during the roughing process, after each reagent is added, the mixture is stirred for 2-5 minutes before adding the next reagent. After the last reagent is added, the mixture is stirred for 2-5 minutes, and the flotation time is 1-5 minutes.

[0023] In some implementations, during the scavenging process, the collector is added and mixed for 2-5 minutes, and the scavenging time is 2-5 minutes.

[0024] In some embodiments, in step S1, the raw ore is ground to a particle size of -0.074mm or more, accounting for more than 60%; after adding water to adjust the slurry, the slurry concentration is 20-40wt%.

[0025] In some embodiments, the ore has a copper grade of ≤1%, an iron grade of 10-20%, and a silicon grade of 10-20%.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] This invention provides the application of a compound with a specific structure as an inhibitor in the separation of copper and sulfur under low alkaline conditions. The compound has a small molecular weight, low viscosity, and good flowability. The functional groups it contains have excellent selective coordination ability to the Fe-S bonds on the surface of pyrite. It can effectively inhibit pyrite under low alkaline conditions (pH=7-8), improve the separation efficiency of chalcopyrite and pyrite minerals, and thus improve the enrichment effect of chalcopyrite.

[0028] The flotation separation method for copper-sulfur ore provided by this invention can efficiently separate chalcopyrite and pyrite under low alkalinity conditions, significantly improving the recovery rate and grade of chalcopyrite and reducing the iron content in chalcopyrite. This achieves efficient flotation separation of copper-sulfur minerals and a substantial increase in copper grade in complex copper sulfide flotation systems. Furthermore, this method does not require high alkalinity conditions, simplifying the reagent formulation, reducing equipment corrosion and the need for treating high-salt, high-alkalinity wastewater, thus lowering costs. The reagents used are also easily degradable and pollution-free, making it environmentally friendly. Attached Figure Description

[0029] Figure 1 The above are process flow diagrams for Embodiment 1 and Comparative Examples 1-3 of the present invention. Detailed Implementation

[0030] Numerous specific details are set forth in the following description to provide a full understanding of the invention. However, the invention can be practiced in many other ways different from those described herein, and similar modifications can be made by those skilled in the art without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0032] The raw ore samples used in the following examples and comparative examples came from a complex low-grade copper sulfide mine in Tibet. The raw ore had a copper grade of 0.68%, an iron grade of approximately 15.25%, and a Si grade of approximately 15.28%. The copper sulfide minerals in the raw ore were mainly chalcopyrite, the iron minerals were mainly pyrite, and the gangue minerals were mainly chlorite, quartz, and mica.

[0033] The mineral processing flow and reagent system of Embodiment 1 and Comparative Examples 1-3 of this invention are as follows: Figure 1 As shown.

[0034] Example 1

[0035] (1) After the raw ore has been ground, particles smaller than 0.074 mm account for more than 70%;

[0036] (2) After the raw ore is ground, depressants, collectors and frothers are added sequentially for flotation, with an interval of 3 minutes between each addition to ensure that the chemical reaction process of the reagents reaches equilibrium. The depressant is the reagent described in this invention. The dosage is 200 g / t, the collector is isopropyl xanthate, the dosage is 15 g / t, and the foaming agent is methyl isobutyl methanol (MIBC), the dosage is 5 g / t.

[0037] (3) After 5 minutes of flotation, rougher concentrate and rougher tailings are obtained. The rougher tailings are then scavenged.

[0038] (4) Add a collector to the roughing tailings slurry for scavenging operation at a dosage of 8 g / t. After 3 minutes of flotation, middlings and tailings products are obtained.

[0039] Comparative Example 1

[0040] Unlike Example 1, Comparative Example 1 did not add inhibitors after grinding, serving as a blank control for the experiment. The remaining steps, reagent dosages, and raw material composition were the same as in Example 1.

[0041] Comparative Examples 2-3

[0042] Unlike Example 1, Comparative Examples 2-3 added sodium carboxymethyl starch and xanthan gum, respectively, after the grinding process. The remaining steps, reagent dosages, and raw material compositions were the same as in Example 1.

[0043] The flotation test results of high-talc copper-molybdenum ore in Example 1 and Comparative Examples 1-3 are shown in Table 1.

[0044] Table 1. Flotation test results of Example 1 and Comparative Examples 1-3

[0045]

[0046] As shown in Table 1 and Figure 1 As shown, Example 1, which uses the reagent system of the present invention, showed significant advantages in the actual separation of complex low-grade copper sulfide ore: the obtained mixed concentrate had a Cu grade of 2.65%, an Fe grade of 24.30%, a Si grade of 3.32%, a Cu recovery rate of 62.26%, and an Fe recovery rate of 25.53%; in contrast, the mixed concentrate of Comparative Example 1 had a Cu grade of only 1.83%, a Cu recovery rate of 45.81%, an Fe grade of 42.44%, and a recovery rate of 46.60%; the mixed concentrates of Comparative Examples 2-3 had Cu grades of 2.17% and 1.79%, respectively, and Cu recovery rates of 60.08% and 26.72%, respectively. In addition, the mixed concentrates had Fe grades of 41.51% and 43.75%, respectively, and the Fe recovery rate was relatively high. The results confirm that the flotation inhibitor of the present invention has the following core characteristics: (1) Strong selectivity: accurately identifies target gangue minerals such as pyrite and produces efficient inhibition, effectively enriching chalcopyrite. (2) Strong inhibition: Significantly blocks pyrite from entering the concentrate product. (3) Innovation and practicality: Significantly enhances its function and has been successfully applied to the field of selective inhibitors for copper-sulfur separation under low alkalinity conditions.

[0047] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.

[0048] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. An inhibitor for efficient separation of copper and sulfur under a low alkalinity condition, characterized by, The inhibitor is a compound shown in formula I: (Formula I); wherein R1, R2, R3, R4 are each independently selected from -R5X, -X, -H, -N + R6 is one of -H, -R5X, -X, -N(R5)2, -OR5, -SR5, -N(R5)2, -N=CR5, -N=N-R5, -N=N, -N=CR5R5, -N=NR5, -N=O, -O-R5, -S-R5, -Si(R5)3, -P(R5)2, -P(R5)3, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P(R5)2, -P R6 is C1-C5 alkyl or C3-C5 cycloalkyl.

2. The depressant for efficiently separating copper and sulfur under a low alkalinity condition according to claim 1, characterized by, R5 is C1-C6 alkyl, C3-C6 cycloalkyl, C3-C6 heterocyclyl, phenyl, benzyl or benzyloxy, and the aromatic ring of the phenyl, benzyl or benzyloxy carries or does not carry a substituent, and the ring of the heterocyclyl carries or does not carry a substituent.

3. The depressant for efficient separation of copper and sulfur under low alkalinity conditions according to claim 1, characterized by, The inhibitor is at least one of the following compounds: 、 、 、 、 、 、 、 、 、 、 、 。 4. A flotation reagent for efficiently separating copper and sulfur under a low alkalinity condition, characterized by, The inhibitor, the collector and the frother, wherein the inhibitor is the inhibitor according to any one of claims 1-3.

5. The flotation reagent according to claim 4, characterized in that, The collector comprises isopropyl xanthate; and the frother comprises methyl isobutyl carbinol.

6. A process for efficient flotation separation of copper and sulphur at low alkalinity conditions, characterized by, The method comprises the following steps: S1, grinding the raw ore, adding water to make a slurry, and obtaining a slurry; S2, adding the flotation reagent according to claim 4 or 5 to the slurry, and performing flotation to obtain a concentrate and a tailing; The flotation process comprises at least one roughing and one scavenging.

7. The process for efficient flotation separation of copper-sulphur at low alkalinity conditions as claimed in claim 6 wherein, In step S2, in the roughing process, the inhibitor, the collector and the frother in the flotation reagent are sequentially added to the slurry, and roughing is performed to obtain a roughing concentrate and a roughing tailing; in the scavenging process, the collector is added to the roughing tailing, and scavenging is performed to obtain a scavenging concentrate and a scavenging tailing; the roughing concentrate is the copper concentrate, and the scavenging tailing is the final tailing.

8. The process for efficient flotation separation of copper-sulphur at low alkalinity conditions as claimed in claim 7 wherein, In the roughing process, the inhibitor is added in an amount of 100-300 g / t; the collector is added in an amount of 7-25 g / t; and the frother is added in an amount of 1-10 g / t; in the scavenging process, the collector is added in an amount of 5-15 g / t.

9. The process for efficient flotation separation of copper-sulphur at low alkalinity conditions according to any one of claims 6 to 8, characterized by, In the raw ore, the copper grade is ≤1%, the iron grade is 10-20%, and the silicon grade is 10-20%.

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