A lead-zinc separation inhibitor and a method of using the same

Abstract

This invention discloses a lead-zinc separation inhibitor and its application method. The inhibitor is obtained by uniformly mixing urea, sodium bicarbonate, and calcium carbide in a ratio of 10:15-50:0.5-3, reacting the mixture at high temperature under the catalysis of a catalyst, cooling and pulverizing the mixture, and then adding zinc sulfate at a mass ratio of 10-20:1 and mixing thoroughly. This invention uses urea, sodium bicarbonate, and calcium carbide as the main components of the lead-zinc separation inhibitor. Through the synergistic effect of these components, lead and zinc can be separated efficiently, improving lead recovery rate. The inhibitor results in high lead-zinc separation efficiency, good separation effect, good stability, and low usage. It solves the technical problems of high toxicity and pollution associated with traditional inhibitors such as sodium cyanide.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, specifically to a lead-zinc separation inhibitor and its application method. Background Technology

[0002] Lead and zinc are among the earliest metals extracted by humans from lead and zinc ores. There are 11 industrial lead minerals and 6 industrial zinc minerals in lead-zinc ore, with galena and sphalerite being the most important. Galena has the chemical formula PbS and a crystal structure that is isometric, with sulfide ions in a cubic close-packed configuration and lead ions filling all the octahedral voids. Sphalerite has the chemical formula...

[0003] ZnS has an isometric crystal system. Zn ions are distributed at the corners of the unit cell and at the center of all faces, while S is located at the center of four of the eight small cubes that the unit cell is divided into.

[0004] my country possesses abundant lead and zinc resources, but with continuous mining, lead and zinc ores are becoming increasingly lean, fine, and complex. To enhance lead and zinc ore recovery, in-depth research has been conducted on various aspects, including processes, reagents, and equipment. The most commonly used recovery process for lead and zinc ore is flotation, with main flotation procedures including preferential flotation, mixed flotation, and equal-floatable processes. When the ore oxidation level is low, sulfide ores are typically floated first, followed by oxide ores, with lead and zinc finally separated. When the ore oxidation level is high, lead minerals are typically floated first, followed by zinc sulfide and zinc oxide minerals in sequence. The selection of flotation reagents is crucial for effective recovery, with collectors, zinc-sulfide mineral depressants, and zinc activators being the most important. There are many types of zinc mineral depressants, with common single depressants including cyanide, zinc sulfate, anhydrous sodium sulfite, sodium sulfide, and sulfur dioxide gas. Sodium cyanide is an effective zinc mineral depressant, with strong inhibition and high selectivity; however, due to cyanide's high toxicity and pollution, its application in modern enterprises is limited. Therefore, seeking an efficient, stable, and environmentally friendly inhibitor is one of the effective means to achieve lead-zinc separation. Summary of the Invention

[0005] The purpose of this invention is to provide a lead-zinc separation inhibitor and its application method. The lead-zinc separation inhibitor provided by this invention can achieve efficient separation of lead and zinc, effectively reduce the zinc grade in lead concentrate, improve lead recovery rate, and is environmentally friendly, non-toxic, and pollution-free, solving the technical problems of high toxicity and pollution of traditional inhibitors such as sodium cyanide.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A lead-zinc separation inhibitor is characterized in that: the inhibitor is obtained by mixing urea, sodium bicarbonate and calcium carbide in a ratio of 10:15~50:0.5~3, reacting them at high temperature under the catalysis of a catalyst, cooling and pulverizing them, and then adding zinc sulfate in a mass ratio of 10~20:1 and mixing them evenly.

[0008] As a preferred technical solution of the present invention, the catalyst includes a metal porphyrin catalyst or a magnetic nanocatalyst.

[0009] As a preferred technical solution of the present invention, the metal porphyrin catalyst includes one or more combinations of tetra(pentafluorophenyl)cobalt porphyrin, tetra(4-nitrophenyl)cobalt porphyrin, and tetra(p-sulfonylphenyl)manganese porphyrin.

[0010] As a preferred technical solution of the present invention, the magnetic nanocatalyst includes one or more combinations of B2O3-Fe3O4, ZrO2-Fe3O4 and Al2O3-Fe3O4.

[0011] As a preferred embodiment of the present invention, the amount of catalyst added is 0.1-1% of the mass of the reactants.

[0012] As a preferred technical solution of the present invention, the high-temperature reaction is carried out at 560-720℃ for 2-8 hours.

[0013] Another object of the present invention is to provide a method for applying a lead-zinc separation inhibitor, comprising the following steps:

[0014] (1) Grinding: The lead-zinc ore is re-ground and classified, and the proportion of particles with a fineness of 0.074 mm is controlled to be above 80%;

[0015] (2) Separation and flotation of lead-zinc ore: The ground lead-zinc ore is subjected to flotation using a process of roughing, cleaning and scavenging, and the lead-zinc separation inhibitor is added to the roughing, cleaning I and cleaning II processes respectively.

[0016] As a preferred technical solution of the present invention, the amount of lead-zinc separation inhibitor used is 600~1500g / t lead-zinc feed.

[0017] As a preferred technical solution of the present invention, the lead grade in the lead-zinc mixed concentrate is 0.3-3% and the zinc grade is 2-15%.

[0018] Compared with the prior art, the advantages and beneficial effects of the present invention include:

[0019] 1. The lead-zinc separation inhibitor provided by this invention can achieve efficient separation of lead and zinc, effectively reduce the zinc grade in lead concentrate, improve lead recovery rate, and is environmentally friendly, non-toxic, and pollution-free, solving the technical problems of high toxicity and pollution of traditional inhibitors such as sodium cyanide.

[0020] 2. This invention uses urea, sodium bicarbonate, and calcium carbide as the main components of the lead-zinc separation inhibitor. Through the coordinated action of each component, lead and zinc can be separated efficiently, improving the lead recovery rate. The inhibitor results in high lead-zinc separation efficiency, good separation effect, good stability, and low usage.

[0021] 3. In the preparation process of the lead-zinc separation inhibitor, the present invention adds a metal porphyrin catalyst or a magnetic nanocatalyst, which has high catalytic efficiency, can effectively improve the production efficiency of the lead-zinc separation inhibitor, improve the selectivity of the synthesized inhibitor, improve the product stability of the inhibitor, and the catalyst can be recycled to reduce production costs. Attached Figure Description

[0022] Figure 1 This is a process flow diagram for the separation and flotation of lead-zinc ore. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1

[0025] A method for preparing a lead-zinc separation inhibitor involves mixing urea, sodium bicarbonate, and calcium carbide in a ratio of 10:40:1, reacting the mixture at 560-720℃ for 3 hours under the catalysis of a catalyst, cooling and pulverizing the mixture, and then adding zinc sulfate at a mass ratio of 15:1 and mixing thoroughly to obtain the lead-zinc separation inhibitor. The catalyst used is tetrakis(4-nitrophenyl)cobalt porphyrin, and the amount added is 0.2% of the total amount of urea, sodium bicarbonate, and calcium carbide reactants.

[0026] An example of applying the aforementioned lead-zinc separation inhibitor to the flotation separation of lead-zinc mixed concentrates is presented. The mineral raw material is a lead-zinc mine in Guangxi, with a lead grade of 2.23% and a zinc grade of 11.04%. The specific process is as follows:

[0027] (1) Grinding: The qualified particle size product after lead-zinc mixed flotation and subsequent grinding and classification is selected as the feed for lead-zinc separation flotation operation, of which 0.074mm particle size accounts for 83%; the flotation operation adopts mechanical stirring flotation machine, which does not require additional air supply and is naturally aspirated.

[0028] (2) Lead-zinc separation flotation operation: The lead-zinc separation flotation adopts a process flow of one roughing, two cleaning, and three scavenging (the specific process flow is attached). Figure 1As shown in the figure, the environmentally friendly lead-zinc separation inhibitor was added to the roughing, cleaning I, and cleaning II processes, respectively. The dosage range of the inhibitor was 600~1500 g / t·feed, the dosage range of ethyl thiocyanate was 30~110 g / t·feed, and the dosage range of No. 2 oil was 20~40 g / t·feed. The final obtained indicators were: lead concentrate yield 5.88%, lead concentrate grade 34.39%, lead recovery rate 90.61%, and zinc content 3.32%.

[0029] Example 2

[0030] A method for preparing a lead-zinc separation inhibitor involves uniformly mixing urea, sodium bicarbonate, and calcium carbide in a ratio of 10:50:1, reacting the mixture at 560-720℃ for 5.5 hours under the catalysis of a catalyst, cooling and pulverizing the mixture, and then adding zinc sulfate at a mass ratio of 12:1 and mixing thoroughly to obtain the lead-zinc separation inhibitor. The catalyst used is a B2O3-Fe3O4 nanocatalyst, added at 0.5% of the total reactants of urea, sodium bicarbonate, and calcium carbide.

[0031] An example of applying the aforementioned lead-zinc separation inhibitor to the flotation separation of lead-zinc mixed concentrates is presented. The mineral raw material is a lead-zinc mine in Guangxi, with a lead grade of 1.28% and a zinc grade of 4.30%. The specific process is as follows:

[0032] Grinding: The qualified particle size product after lead-zinc mixed flotation and subsequent grinding and classification is selected as the feed for lead-zinc separation flotation operation, of which the 0.074mm particle size accounts for 85%;

[0033] Lead-zinc separation flotation operation: The lead-zinc separation flotation adopts a process flow of one rougher, two cleaners, and three scavengers. The aforementioned environmentally friendly lead-zinc separation depressant is added in the rougher, cleaner I, and cleaner II stages, respectively. The dosage range of the depressant is 600~1500 g / t·feed, the dosage range of ethyl thiocyanate is 60~140 g / t·feed, and the dosage range of No. 2 oil is 20~40 g / t·feed. The final obtained indicators are: lead concentrate yield 5.64%, lead concentrate grade 19.00%, lead recovery rate 83.72%, and zinc content 3.24%.

[0034] Example 3

[0035] A method for preparing a lead-zinc separation inhibitor involves mixing urea, sodium bicarbonate, and calcium carbide in a ratio of 10:25:1, reacting the mixture at 560-720℃ for 4 hours under the catalysis of a catalyst, cooling and pulverizing the mixture, and then adding zinc sulfate at a mass ratio of 20:1 and mixing thoroughly to obtain the lead-zinc separation inhibitor. The catalyst used is tetratetra(pentafluorophenyl)cobalt porphyrin, and the amount added is 0.1% of the total amount of urea, sodium bicarbonate, and calcium carbide reactants.

[0036] An example of applying the aforementioned lead-zinc separation inhibitor to the flotation separation of lead-zinc mixed concentrates is presented. The mineral raw material is a lead-zinc mine in Guangxi, with a lead grade of 0.24% and a zinc grade of 1.80%. The specific process is as follows:

[0037] Grinding: The qualified particle size product after lead-zinc mixed flotation and subsequent grinding and classification is selected as the feed for lead-zinc separation flotation operation, of which the -0.074mm particle size accounts for 88%;

[0038] Lead-zinc separation flotation operation: The lead-zinc separation flotation adopts a process flow of one rougher, two cleaners, and three scavengers. The aforementioned environmentally friendly lead-zinc separation depressant is added in the rougher, cleaner I, and cleaner II stages, respectively. The dosage range of the depressant is 600~1500 g / t·feed, the dosage range of ethyl thiocyanate is 60~140 g / t·feed, and the dosage range of No. 2 oil is 20~40 g / t·feed. The final obtained indicators are: lead concentrate yield 0.95%, lead concentrate grade 18.46%, lead recovery rate 73.08%, and zinc content 2.14%.

[0039] Comparative Example 1

[0040] A method for preparing a lead-zinc separation inhibitor involves mixing urea and sodium bicarbonate in a 10:40 ratio, reacting the mixture at 560-720℃ for 3 hours under the catalysis of a catalyst, cooling and pulverizing the mixture, and then adding zinc sulfate at a mass ratio of 15:1 and mixing thoroughly to obtain the lead-zinc separation inhibitor. The catalyst used is tetrakis(4-nitrophenyl)cobalt porphyrin, and the amount added is 0.2% of the total amount of urea and sodium bicarbonate reactants.

[0041] An example of applying the aforementioned lead-zinc separation inhibitor to the flotation separation of lead-zinc mixed concentrates is presented. The mineral raw material is a lead-zinc mine in Guangxi, with a lead grade of 2.23% and a zinc grade of 11.04%. The specific process is as follows:

[0042] (1) Grinding: The qualified particle size product after lead-zinc mixed flotation and subsequent grinding and classification is selected as the feed for lead-zinc separation flotation operation, of which 0.074mm particle size accounts for 83%; the flotation operation adopts mechanical stirring flotation machine, which does not require additional air supply and is naturally aspirated.

[0043] (2) Lead-zinc separation flotation operation: The lead-zinc separation flotation adopts a process flow of one roughing, two cleaning, and three scavenging (the specific process flow is attached). Figure 1 As shown in the figure, the environmentally friendly lead-zinc separation inhibitor was added to the roughing, cleaning (I), and cleaning (II) processes, respectively. The dosage range of the inhibitor was 600~1500 g / t·feed, the dosage range of ethyl thiocyanate was 30~110 g / t·feed, and the dosage range of No. 2 oil was 20~40 g / t·feed. The final results were: lead concentrate yield 4.13%, lead concentrate grade 24.38%, lead recovery rate 45.15%, and zinc content 6.97%.

[0044] Comparative Example 2

[0045] A method for preparing a lead-zinc separation inhibitor involves mixing sodium bicarbonate and calcium carbide in a 40:1 ratio, reacting the mixture at 560-720℃ for 3 hours under the catalysis of a catalyst, cooling and pulverizing the mixture, and then adding zinc sulfate in a 15:1 mass ratio and mixing thoroughly to obtain the lead-zinc separation inhibitor. The catalyst used is tetrakis(4-nitrophenyl)cobalt porphyrin, and the amount added is 0.2% of the total amount of sodium bicarbonate and calcium carbide reactants.

[0046] An example of applying the aforementioned lead-zinc separation inhibitor to the flotation separation of lead-zinc mixed concentrates is presented. The mineral raw material is a lead-zinc mine in Guangxi, with a lead grade of 2.23% and a zinc grade of 11.04%. The specific process is as follows:

[0047] (1) Grinding: The qualified particle size product after lead-zinc mixed flotation and subsequent grinding and classification is selected as the feed for lead-zinc separation flotation operation, of which 0.074mm particle size accounts for 83%; the flotation operation adopts mechanical stirring flotation machine, which does not require additional air supply and is naturally aspirated.

[0048] (2) Lead-zinc separation flotation operation: The lead-zinc separation flotation adopts a process flow of one roughing, two cleaning, and three scavenging (the specific process flow is attached). Figure 1 As shown in the figure, the environmentally friendly lead-zinc separation inhibitor was added to the roughing, cleaning I, and cleaning II processes, respectively. The dosage range of the inhibitor was 600~1500 g / t·feed, the dosage range of ethyl thiocyanate was 30~110 g / t·feed, and the dosage range of No. 2 oil was 20~40 g / t·feed. The final obtained indicators were: lead concentrate yield 4.66%, lead concentrate grade 28.62%, lead recovery rate 58.99%, and zinc content 5.37%.

[0049] Comparative Example 3

[0050] A method for preparing a lead-zinc separation inhibitor involves mixing urea and calcium carbide in a 10:1 ratio, reacting the mixture at 560-720℃ for 3 hours under the catalysis of a catalyst, cooling and pulverizing the mixture, and then adding zinc sulfate in a 15:1 mass ratio and mixing thoroughly to obtain the lead-zinc separation inhibitor. The catalyst used is tetrakis(4-nitrophenyl)cobalt porphyrin, and the amount added is 0.2% of the total amount of urea and calcium carbide reactants.

[0051] An example of applying the aforementioned lead-zinc separation inhibitor to the flotation separation of lead-zinc mixed concentrates is presented. The mineral raw material is a lead-zinc mine in Guangxi, with a lead grade of 2.23% and a zinc grade of 11.04%. The specific process is as follows:

[0052] (1) Grinding: The qualified particle size product after lead-zinc mixed flotation and subsequent grinding and classification is selected as the feed for lead-zinc separation flotation operation, of which 0.074mm particle size accounts for 83%; the flotation operation adopts mechanical stirring flotation machine, which does not require additional air supply and is naturally aspirated.

[0053] (2) Lead-zinc separation flotation operation: The lead-zinc separation flotation adopts a process flow of one roughing, two cleaning, and three scavenging (the specific process flow is attached). Figure 1 As shown in the figure, the environmentally friendly lead-zinc separation inhibitor was added to the roughing, cleaning I, and cleaning II processes, respectively. The dosage range of the inhibitor was 600~1500 g / t·feed, the dosage range of ethyl thiocyanate was 30~110 g / t·feed, and the dosage range of No. 2 oil was 20~40 g / t·feed. The final obtained indicators were: lead concentrate yield 4.21%, lead concentrate grade 20.55%, lead recovery rate 37.96%, and zinc content 8.02%.

[0054] Comparative Example 4

[0055] A method for preparing a lead-zinc separation inhibitor: urea, sodium bicarbonate, and calcium carbide are mixed evenly in a ratio of 10:40:1, reacted at a high temperature of 560-720℃ for 3 hours, cooled and pulverized, and then zinc sulfate is added at a mass ratio of 15:1 and mixed evenly to obtain the lead-zinc separation inhibitor.

[0056] An example of applying the aforementioned lead-zinc separation inhibitor to the flotation separation of lead-zinc mixed concentrates is presented. The mineral raw material is a lead-zinc mine in Guangxi, with a lead grade of 2.23% and a zinc grade of 11.04%. The specific process is as follows:

[0057] (1) Grinding: The qualified particle size product after lead-zinc mixed flotation and subsequent grinding and classification is selected as the feed for lead-zinc separation flotation operation, of which 0.074mm particle size accounts for 83%; the flotation operation adopts mechanical stirring flotation machine, which does not require additional air supply and is naturally aspirated.

[0058] (2) Lead-zinc separation flotation operation: The lead-zinc separation flotation adopts a process flow of one roughing, two cleaning, and three scavenging (the specific process flow is attached). Figure 1 As shown in the figure, the environmentally friendly lead-zinc separation inhibitor was added to the roughing, cleaning I, and cleaning II processes, respectively. The dosage range of the inhibitor was 600~1500 g / t·feed, the dosage range of ethyl thiocyanate was 30~110 g / t·feed, and the dosage range of No. 2 oil was 20~40 g / t·feed. The final obtained indicators were: lead concentrate yield 5.61%, lead concentrate grade 31.06%, lead recovery rate 78.14%, and zinc content 3.92%.

[0059] The above description, in conjunction with specific / preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the inventive concept, and all such substitutions or modifications should be considered within the scope of protection of the present invention.

Claims

1. A lead-zinc separation inhibitor, characterized in that: The inhibitor is prepared by mixing urea, sodium bicarbonate, and calcium carbide in a ratio of 10:15~50:0.5~3, reacting them at high temperature under the catalysis of a catalyst, cooling and pulverizing the mixture, and then adding zinc sulfate in a mass ratio of 10~20:1 and mixing thoroughly. The catalyst includes metal porphyrin catalysts or magnetic nanocatalysts. The metalloporphyrin catalyst includes one or more combinations of tetra(pentafluorophenyl)cobalt porphyrin, tetra(4-nitrophenyl)cobalt porphyrin, and tetra(p-sulfonylphenyl)manganese porphyrin; The magnetic nanocatalyst includes one or more combinations of B2O3-Fe3O4, ZrO2-Fe3O4 and Al2O3-Fe3O4; The amount of catalyst added is 0.1-1% of the reactant mass.

2. The lead-zinc separation inhibitor according to claim 1, characterized in that: The high-temperature reaction is carried out at 560-720℃ for 2-8 hours.

3. The application method of the lead-zinc separation inhibitor as described in claim 1 or claim 2, characterized in that: Includes the following steps: (1) Grinding: The lead-zinc ore is re-ground and classified, and the proportion of particles with a fineness of 0.074 mm is controlled to be above 80%; (2) Lead-zinc separation flotation: The ground lead-zinc ore is subjected to flotation using a roughing, cleaning and scavenging process, and the lead-zinc separation inhibitor is added to the roughing, cleaning I and cleaning II processes respectively.

4. The application method of the lead-zinc separation inhibitor according to claim 3, characterized in that: The dosage of the lead-zinc separation inhibitor is 600~1500 g / t lead-zinc feed.

5. The application method of the lead-zinc separation inhibitor according to claim 3, characterized in that: The lead-zinc ore has a lead grade of 0.3-3% and a zinc grade of 2-15%.

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