A new scheelite collector and its heating cleaning beneficiation process

Abstract

The application discloses a novel scheelite collector and a heating cleaning beneficiation process, and relates to the technical field of beneficiation. The application forms an oxime acid benzene alkene compound by using 4-vinyl ethyl acetate and hydroxylamine hydrochloride, and then polymerizes the oxime acid benzene alkene compound with 4-hydroxy styrene and di-vinyl benzene to form a hydrophobic microsphere. The hydrophobic microsphere is used to form a relatively stable surface adsorption with scheelite through hydrophobic association and chemical bonding, and to drive the scheelite to float, so that the scheelite and fluorite are effectively separated. Then, the collector is prepared by mixing the hydrophobic microsphere, 1-formamido-1-cyclopropane carboxylic acid and other raw materials. The 1-formamido-1-cyclopropane carboxylic acid is used to change the hydrophilicity of the fluorite, to inhibit the floatability of the fluorite, and to realize the rapid separation effect. Then, the combination process of one-time normal-temperature rough separation, twice cleaning and one-time heating cleaning is used, so that the recovery rate of WO3 in the scheelite concentrate is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, specifically to a novel scheelite collector and its heating and beneficiation process. Background Technology

[0002] Tungsten, as a non-renewable resource, has wide applications in industrial production. However, after long-term mining, wolframite resources are becoming increasingly depleted, and scheelite is gradually replacing wolframite as the main tungsten mining type. Currently, scheelite beneficiation mainly uses flotation technology, with bubble flotation being the most common method. This method causes the floated mineral particles to adhere to bubbles for collection. However, the generation of bubbles is greatly affected by the pulp concentration, and during the flotation process, bubble coalescence and ore particle detachment can occur, making it uncontrollable.

[0003] In addition, the collector added during the flotation process collects minerals by changing the surface properties of the minerals. It has two basic properties: (1) it can selectively adsorb onto the surface of the minerals; (2) it can increase the hydrophobicity of the mineral surface, making it easier to adhere to the air bubbles, thereby improving the floatability of the minerals. For quartz-type scheelite, since its gangue minerals are mainly silicates, quartz and other minerals, the separation is relatively simple; however, for scheelite containing high-calcium minerals such as fluorite, calcite, and barite, since the surface properties of these gangue minerals are similar to those of scheelite, the floatability of the gangue minerals and scheelite is very similar, making flotation separation very difficult. Summary of the Invention

[0004] The purpose of this invention is to provide a novel scheelite collector and its heating and beneficiation process to solve the problems existing in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a novel scheelite collector, wherein the novel scheelite collector is prepared by mixing sodium oleate, hydrophobic microspheres, and 1-formamido-1-cyclopropanecarboxylic acid in a mass ratio of 3:2:1 to 6:5:1.

[0006] Furthermore, the hydrophobic microspheres are prepared by the following method: 4-hydroxystyrene, divinylbenzene, oxime phenylene compound, azobisisobutyronitrile, and acetonitrile are mixed and reacted at 80-90℃ for 5-7h. After cooling to room temperature, the mixture is centrifuged at 6000-7000rpm for 2min, filtered, and the solid is washed three times with toluene and anhydrous ethanol, respectively, and dried at 60℃ for 24h.

[0007] Furthermore, the oxime phenylene compound is prepared by the following method: hydroxylamine hydrochloride and methanol are mixed in a mass ratio of 0.3:3 to 0.5:6, potassium hydroxide is added until the solution pH is 10, and then ethyl 4-vinylphenylacetate is added in a mass ratio of 1 to 3 times that of hydroxylamine hydrochloride. The mixture is stirred at 30 to 50 rpm for 8 to 12 hours, extracted with ethyl acetate, and the organic phase is collected. Hydrochloric acid is added until the solution pH is 4 to 6, and the mixture is washed 3 to 5 times with saturated brine. The solution is dried with anhydrous magnesium sulfate for 1.5 hours, filtered, and the filtrate is collected. The filtrate is distilled at a vacuum of 1.4 to 2.6 kPa and a temperature of 35 to 49°C for 2 to 3 hours.

[0008] Furthermore, the mass ratio of 4-hydroxystyrene, divinylbenzene, oxime phenylene compound, azobisisobutyronitrile, and acetonitrile is 0.1~0.4:0.4~0.6:0.1~0.4:0.01~0.03:28~33.

[0009] A method for heating and refining using the collectors described in claims 1-4, comprising the following steps:

[0010] (1) Grind the tungsten-containing flotation tailings to a particle size of less than 0.074 mm, with 75-85% of the particles being added to deionized water and mixed evenly to obtain a slurry;

[0011] (2) The slurry is subjected to one roughing and two cleaning processes to capture the fine ore A floating on the surface, and the bottom product is subjected to one roughing and two cleaning processes again for enrichment;

[0012] (3) Add acetone to the selected ore to a concentration of 50-60%, stir for 3-8 minutes, raise the temperature to 65-70℃, continue stirring for 30-50 minutes, after the de-removal is completed, add deionized water to dilute to a concentration of 30-40%, and carry out heated selection. The heated selection process consists of one roughing and two selections, with a temperature of 90-95℃. Collect the selected ore B floating on the surface, and carry out de-removal treatment to obtain scheelite concentrate.

[0013] Furthermore, the tungsten trioxide content in the tungsten flotation tailings in step (1) is 0.08~0.25%, and the fluorite content is 4.2~14.0%.

[0014] Furthermore, the slurry concentration in step (1) is 20-30%.

[0015] Furthermore, the specific process of roughing in steps (2) and (3) is as follows: add sodium carbonate until the pH of the slurry is 7-11, stir for 3-8 minutes, and then add 1500-2000 g / t of water glass. 尾矿 After stirring for 3-8 minutes, add 300-500 g / t of the new scheelite collector. 尾矿 Continue stirring for 8-15 minutes.

[0016] Furthermore, in steps (2) and (3), 60-180 g / t of a collector is added to the selected material. 尾矿 Selected product 2, add 30-50g / t of collector. 尾矿 .

[0017] Furthermore, the stirring speed is 1000~2000 rpm.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0019] This invention utilizes a mixture of hydrophobic microspheres and 1-formamido-1-cyclopropanecarboxylic acid to prepare a collector that effectively separates scheelite and fluorite. The carboxyl groups in 1-formamido-1-cyclopropanecarboxylic acid interact with calcium particles on the surfaces of scheelite and fluorite, resulting in chemical adsorption on the mineral surfaces. The adsorption is stronger on the fluorite surface. Simultaneously, the amide groups in the molecular structure form chelate adsorption on the fluorite surface, thereby encapsulating 1-formamido-1-cyclopropanecarboxylic acid on the fluorite surface and hindering the adsorption of hydrophobic microspheres on the fluorite surface, thus enhancing the separation effect. Furthermore, the hydrophilicity of 1-formamido-1-cyclopropanecarboxylic acid enhances the hydrophilicity of fluorite, thereby suppressing the floatability of fluorite and causing it to sink to the bottom of the tank.

[0020] First, this invention utilizes the reaction of the ester group of ethyl 4-vinylphenylacetate with hydroxylamine hydrochloride to form an oxime acid structure, which allows the collector to bond with scheelite, forming a relatively stable surface adsorption and increasing the flotation effect. Then, relying on the double bond, it polymerizes with 4-hydroxystyrene and divinylbenzene to form hydrophobic microspheres, which serve as a carrier. These microspheres hydrophobically associate with the ground fine scheelite and work synergistically with the oxime acid groups, causing the scheelite to adhere to the carrier and recover the scheelite. At the same time, the low surface energy and hydrophobic properties of the microspheres can drive the scheelite to float, thereby effectively separating scheelite and fluorite. In addition, the hydroxyl and oxime acid in the hydrophobic microspheres give them a certain degree of hydrophilicity, allowing them to be uniformly dispersed in the scheelite slurry without dissolving. After re-adsorbing the scheelite, the hydrophobicity plays a dominant role, driving the scheelite to float. Using hydrophobic microspheres for flotation can avoid the aeration step and prevent the uncontrollable adhesion of bubbles to the scheelite, thereby achieving a rapid separation effect.

[0021] Secondly, this invention designs a combined process for scheelite, consisting of one ambient temperature roughing, two cleaning processes, and one heated cleaning process, to improve the recovery rate. Before ambient temperature roughing, grinding is used to form micron-sized fine particles, which is beneficial for the adhesion of hydrophobic microspheres. In the heated cleaning process, acetone is added as a solvent to remove the hydrophobic microspheres, and the acetone is removed by heating, thereby effectively removing the collector on the surface of the scheelite concentrate without any residue, greatly improving the quality of the scheelite. Detailed Implementation

[0022] 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. Example 1

[0023] Hydroxylamine hydrochloride and methanol were mixed at a mass ratio of 0.3:3. Potassium hydroxide was added until the pH of the solution was 10. Then, ethyl 4-vinylphenylacetate was added at a mass ratio of 1:1 that of hydroxylamine hydrochloride. The mixture was stirred at 30 rpm for 8 h. The mixture was extracted with ethyl acetate, and the organic phase was collected. Hydrochloric acid was added until the pH of the solution was 4. The mixture was washed three times with saturated brine and dried with anhydrous magnesium sulfate for 1.5 h. The mixture was filtered, and the filtrate was distilled at 35 °C under a vacuum of 1.4 kPa for 2 h to obtain the oxime phenylene compound.

[0024] 4-hydroxystyrene, divinylbenzene, oxime phenylene compound, azobisisobutyronitrile, and acetonitrile were mixed and reacted at 80°C for 5 h. After cooling to room temperature, the mixture was centrifuged at 6000 rpm for 2 min, filtered, and the solid was washed three times with toluene and anhydrous ethanol, respectively. The solid was then dried at 60°C for 24 h to obtain hydrophobic microspheres.

[0025] (3) A novel scheelite collector was prepared by mixing sodium oleate, hydrophobic microspheres, and 1-formamido-1-cyclopropanecarboxylic acid in a mass ratio of 3:2:1.

[0026] (4) Grind the tungsten-containing flotation tailings to a particle size of less than 0.074 mm (75%), add deionized water and mix evenly to obtain a slurry with a concentration of 20%; the tungsten-containing flotation tailings contain 0.08% tungsten trioxide and 4.2% fluorite.

[0027] (5) The slurry is subjected to one roughing and two cleaning processes to capture the fine ore A floating on the surface, and the bottom product is subjected to one roughing and two cleaning processes again for enrichment.

[0028] (6) Add acetone to the selected ore to a concentration of 50%, stir at 1000 rpm for 3 min, heat to 65℃, continue stirring for 30 min, after the de-reagent is removed, add deionized water to dilute to a concentration of 30%, and carry out heated selection. The heated selection process consists of one roughing and two selections, with a temperature of 90℃. Collect the selected ore B floating on the surface, and carry out de-reagent treatment to obtain scheelite concentrate.

[0029] Furthermore, the specific process of roughing in steps (5) and (6) is as follows: add sodium carbonate until the slurry pH is 7, stir at 1000 rpm for 3 minutes, and then add 1500 g / t of water glass. 尾矿 After stirring for another 3 minutes, add 300g / t of the new scheelite collector. 尾矿Continue stirring for 8 minutes.

[0030] Furthermore, in steps (5) and (6), 60 g / t of the selected material is added to the collector. 尾矿 Selected product 2, with 30g / t of collector added. 尾矿 . Example 2

[0031] (1) Hydroxylamine hydrochloride and methanol were mixed at a mass ratio of 0.4:4.5. Potassium hydroxide was added until the pH of the solution was 10. Then, ethyl 4-vinylphenylacetate was added at twice the mass of hydroxylamine hydrochloride. The mixture was stirred at 40 rpm for 10 h. The organic phase was extracted with ethyl acetate. Hydrochloric acid was added until the pH of the solution was 5. The mixture was washed 4 times with saturated brine. The solution was dried with anhydrous magnesium sulfate for 1.5 h. The mixture was filtered. The filtrate was distilled at a vacuum of 2 kPa and 42 °C for 2.5 h to obtain oxime phenylene compound.

[0032] (2) Mix 4-hydroxystyrene, divinylbenzene, oxime phenylene compound, azobisisobutyronitrile and acetonitrile, react at 85°C for 6 h, cool to room temperature, centrifuge at 6500 rpm for 2 min, filter, take the solid, wash with toluene and anhydrous ethanol 3 times respectively, and dry at 60°C for 24 h to obtain hydrophobic microspheres.

[0033] (3) A novel scheelite collector was prepared by mixing sodium oleate, hydrophobic microspheres, and 1-formamido-1-cyclopropanecarboxylic acid in a mass ratio of 4.5:3.5:1.

[0034] (4) Grind the tungsten-containing flotation tailings to a particle size of less than 0.074 mm (80%), add deionized water and mix evenly to obtain a slurry with a concentration of 25%; the tungsten trioxide content in the tungsten-containing flotation tailings is 0.16% and the fluorite content is 8.8%;

[0035] (5) The slurry is subjected to one roughing and two cleaning processes to capture the fine ore A floating on the surface, and the bottom product is subjected to one roughing and two cleaning processes again for enrichment.

[0036] (6) Add acetone to the selected ore to a concentration of 55%, stir at 1500 rpm for 5 min, heat to 68℃, continue stirring for 40 min, after the de-reagent is removed, add deionized water to dilute to a concentration of 35%, and carry out heated selection. The heated selection process consists of one roughing and two selections, with a temperature of 92℃. Collect the selected ore B floating on the surface, and carry out de-reagent treatment to obtain scheelite concentrate.

[0037] Furthermore, the specific process of roughing in steps (5) and (6) is as follows: add sodium carbonate until the slurry pH is 7, stir at 1500 rpm for 5 minutes, and then add 1750 g / t of water glass. 尾矿 After stirring for another 5 minutes, add 400g / t of the new scheelite collector. 尾矿Continue stirring for 11 minutes.

[0038] Furthermore, in steps (5) and (6), 120 g / t of collector is added to the selected 1. 尾矿 Selected product 2 with 40g / t of collector added 尾矿 . Example 3

[0039] Hydroxylamine hydrochloride and methanol were mixed at a mass ratio of 0.5:6. Potassium hydroxide was added until the pH of the solution was 10. Then, ethyl 4-vinylphenylacetate was added in a mass ratio of 3 times that of hydroxylamine hydrochloride. The mixture was stirred at 50 rpm for 12 h. The mixture was extracted with ethyl acetate, and the organic phase was collected. Hydrochloric acid was added until the pH of the solution was 6. The mixture was washed 5 times with saturated brine and dried with anhydrous magnesium sulfate for 1.5 h. The mixture was filtered, and the filtrate was distilled at 49 °C under a vacuum of 2.6 kPa for 3 h to obtain oxime phenylene compounds.

[0040] 4-hydroxystyrene, divinylbenzene, oxime phenylene compound, azobisisobutyronitrile, and acetonitrile were mixed and reacted at 90°C for 7 h. After cooling to room temperature, the mixture was centrifuged at 7000 rpm for 2 min, filtered, and the solid was washed three times with toluene and anhydrous ethanol, respectively. The solid was then dried at 60°C for 24 h to obtain hydrophobic microspheres.

[0041] (3) A novel scheelite collector was prepared by mixing sodium oleate, hydrophobic microspheres, and 1-formamido-1-cyclopropanecarboxylic acid in a mass ratio of 6:5:1.

[0042] (4) Grind the tungsten-containing flotation tailings to a particle size of less than 0.074 mm (85%), add deionized water and mix evenly to obtain a slurry with a concentration of 30%; the tungsten trioxide content in the tungsten-containing flotation tailings is 0.25% and the fluorite content is 14.0%;

[0043] (5) The slurry is subjected to one roughing and two cleaning processes to capture the fine ore A floating on the surface, and the bottom product is subjected to one roughing and two cleaning processes again for enrichment.

[0044] (6) Add acetone to the selected ore to a concentration of 60%, stir at 2000 rpm for 8 min, heat to 70℃, continue stirring for 50 min, after the de-removal is completed, add deionized water to dilute to a concentration of 40%, and carry out heated selection. The heated selection process consists of one roughing and two selections, with a temperature of 95℃. Collect the selected ore B floating on the surface, and carry out de-removal treatment to obtain scheelite concentrate.

[0045] Furthermore, the specific process of roughing in steps (5) and (6) is as follows: add sodium carbonate until the slurry pH is 7, stir at 2000 rpm for 8 minutes, and then add 2000 g / t of water glass. 尾矿 After stirring for another 8 minutes, add 500g / t of the new scheelite collector. 尾矿 Continue stirring for 15 minutes.

[0046] Furthermore, in steps (5) and (6), 180 g / t of collector is added to the selected product 1. 尾矿 Selected product 2, with 50g / t of collector added. 尾矿 .

[0047] Comparative Examples 1-4

[0048] The difference between Comparative Examples 1-4 and Example 2 lies in the pH value of the slurry; the other steps are the same as in Example 2.

[0049] Comparative Example 5

[0050] The difference between Comparative Example 5 and Example 2 is that steps (1) to (2) are omitted, and step (3) is changed to: sodium oleate and 1-formamido-1-cyclopropanecarboxylic acid are mixed at a mass ratio of 4.5:1 to prepare a new scheelite collector. The remaining steps are the same as in Example 2.

[0051] Comparative Example 6

[0052] The difference between Comparative Example 6 and Example 2 lies in step (3). Step (3) is changed to: Sodium oleate and hydrophobic microspheres are mixed in a mass ratio of 4.5:3.5 to prepare a new type of scheelite collector. The remaining steps are the same as in Example 2.

[0053] Example of effect

[0054] Table 1 below shows the performance analysis results of WO3 recovery rate and pulp pH value in scheelite concentrate using Example 2 of the present invention and Comparative Examples 1 to 4; Table 2 below shows the performance analysis results of WO3 recovery rate in scheelite using Example 1 to 3 of the present invention and Comparative Examples 5 to 6.

[0055] Table 1

[0056]

[0057] Table 2

[0058]

[0059] A comparison of the experimental data from Examples 1-3 reveals that the collector prepared by the present invention, composed of hydrophobic microspheres and 1-formamido-1-cyclopropanecarboxylic acid, exhibits excellent flotation performance and significantly improves the recovery rate of scheelite. A comparison of the experimental data from Comparative Examples 1-4 with Example 2 shows that the present invention reduces alkali consumption and provides highly efficient flotation for scheelite. A comparison of the experimental data from Comparative Example 5 with Example 2 reveals that the hydrophobic microspheres of the present invention form stable surface adsorption with scheelite, simultaneously driving the scheelite to float, effectively separating scheelite and fluorite, avoiding the uncontrollability of bubble flotation, and achieving rapid separation. A comparison of the experimental data from Comparative Example 6 with Example 2 reveals that the addition of 1-formamido-1-cyclopropanecarboxylic acid in the present invention forms chelating adsorption on the fluorite surface, hindering the adsorption of hydrophobic microspheres on the fluorite surface, while simultaneously enhancing the hydrophilicity of fluorite, inhibiting its floatability, causing it to sink to the bottom of the tank, and thus strengthening the separation effect.

[0060] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A novel scheelite collector, characterized in that, The novel scheelite collector is prepared by mixing sodium oleate, hydrophobic microspheres, and 1-formamido-1-cyclopropanecarboxylic acid in a mass ratio of 3:2:1 to 6:5:

1. The hydrophobic microspheres are prepared by the following method: 4-hydroxystyrene, divinylbenzene, oxime phenylene compound, azobisisobutyronitrile, and acetonitrile are mixed and reacted at 80-90℃ for 5-7h. After cooling to room temperature, the mixture is centrifuged at 6000-7000rpm for 2min, filtered, and the solid is washed three times with toluene and anhydrous ethanol, and dried at 60℃ for 24h.

2. The novel scheelite collector according to claim 1, characterized in that, The oxime phenylene compound is prepared by the following method: hydroxylamine hydrochloride and methanol are mixed in a mass ratio of 0.3:3 to 0.5:6, potassium hydroxide is added until the pH of the solution is 10, and then ethyl 4-vinylphenylacetate is added in a mass ratio of 1 to 3 times that of hydroxylamine hydrochloride. The mixture is stirred at 30 to 50 rpm for 8 to 12 hours, extracted with ethyl acetate, and the organic phase is collected. Hydrochloric acid is added until the pH of the solution is 4 to 6, and the mixture is washed 3 to 5 times with saturated brine. The solution is dried with anhydrous magnesium sulfate for 1.5 hours, filtered, and the filtrate is collected. The filtrate is distilled at a vacuum of 1.4 to 2.6 kPa and a temperature of 35 to 49°C for 2 to 3 hours.

3. The novel scheelite collector according to claim 1, characterized in that, The mass ratio of 4-hydroxystyrene, divinylbenzene, oxime phenylene compound, azobisisobutyronitrile, and acetonitrile is 0.1~0.4:0.4~0.6:0.1~0.4:0.01~0.03:28~33.

4. A method for heating and refining using the collector according to any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Grind the tungsten-containing flotation tailings to a particle size of less than 0.074 mm, with 75-85% of the particles being smaller, add deionized water and mix evenly to obtain a slurry; (2) The slurry is subjected to one roughing and two cleaning processes to capture the fine ore A floating on the surface, and the bottom product is subjected to one roughing and two cleaning processes again for enrichment; (3) Add acetone to the selected ore to a concentration of 50-60%, stir for 3-8 minutes, raise the temperature to 65-70℃, continue stirring for 30-50 minutes, after the de-removal is completed, add deionized water to dilute to a concentration of 30-40%, and carry out heated selection. The heated selection process consists of one roughing and two selections, with a temperature of 90-95℃. Collect the selected ore B floating on the surface, and carry out de-removal treatment to obtain scheelite concentrate. The specific process of roughing in steps (2) and (3) is as follows: add sodium carbonate until the pH of the slurry is 7-11, stir for 3-8 minutes, and then add 1500-2000 g / t of water glass. 尾矿 After stirring for 3-8 minutes, add 300-500 g / t of the new scheelite collector. 尾矿 Continue stirring for 8-15 minutes.

5. The heating and refining method according to claim 4, characterized in that, The tungsten trioxide content in the tungsten flotation tailings in step (1) is 0.08~0.25%, and the fluorite content is 4.2~14.0%.

6. The heating and refining method according to claim 4, characterized in that, The slurry concentration in step (1) is 20-30%.

7. The heating and refining method according to any one of claims 4 to 6, characterized in that, The stirring speed is 1000~2000 rpm.

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