Process for the preparation of ammonium paratungstate from grinding waste

Abstract

The application belongs to the field of tungsten hydrometallurgy, and particularly relates to a method for preparing ammonium paratungstate from grinding waste, comprising the following steps: subjecting the grinding waste containing tungsten carbide to acid leaching and roasting to obtain tungsten oxide; subjecting the tungsten oxide to ball milling, wherein the ball-to-material ratio is 3:1-6:1, and the time is 4-6 h; subjecting the ball-milled tungsten oxide to potassium removal using a potassium removal reagent, wherein the potassium removal reagent comprises hydrochloric acid and ethyl acetate; and subjecting the potassium-removed tungsten oxide to ammonia dissolution crystallization to obtain ammonium paratungstate. The application optimizes the grinding process by adjusting the ball milling parameters, thereby obtaining uniform and fine tungsten oxide particles, so as to improve the subsequent potassium removal efficiency; the specific potassium removal reagent is configured to remove potassium elements at the front end, thereby avoiding the subsequent complex separation and purification steps and reducing the production cost; the potassium content of the tungsten oxide is reduced, thereby effectively improving the purity and quality of the final product; and the application is suitable for grinding waste treatment under different environmental conditions, and has strong environmental adaptability and flexibility.

Description

Technical Field

[0001] This application pertains to the field of hydrometallurgy of tungsten, specifically a method for preparing ammonium paratungstate from grinding waste. Background Technology

[0002] The new process for recycling cemented carbide grinding waste features a short process flow, low pollution, and high efficiency. A key technical issue in this process is controlling the potassium content in the grinding waste. The presence of potassium can severely affect the purity and performance of tungsten products; therefore, the potassium content must be strictly controlled during production.

[0003] The excessive potassium levels are due to some grinding waste entering the storage container via ditches after cutting and grinding. During this process, sand and gravel carried by the waste, along with rainwater entering the ditches, are primarily composed of feldspar and mica. This waste is then recycled into the system. However, cutting fluid, wash water, and other waste, including debris from the ditches, also enter the system. Currently, there is no effective way to address this issue within the recycling system.

[0004] Traditional tungsten concentrate processing typically involves leaching with ammonium tungstate or sodium tungstate solutions. However, potassium has high solubility in these solutions, making effective removal difficult. Furthermore, once potassium ions enter the solution, especially in an ammonium system, there are almost no effective methods to reduce potassium ion levels to meet national standards. Therefore, it is essential to purify and eliminate potassium ions before they enter the ammonium solution system.

[0005] The existing technology (CN118637662B) uses a "roasting-ball milling-acid leaching-ammonia leaching" process to treat wolframite concentrate, which can indeed effectively remove potassium and produce qualified APT products. However, when processing cemented carbide grinding waste, we found that this process has obvious limitations: although the acid leaching and roasting steps have a certain potassium removal effect, the potassium removal efficiency is significantly reduced for special raw materials such as grinding waste, making it difficult to achieve the ideal purity requirements.

[0006] Therefore, optimizing the potassium removal process based on existing technologies and establishing a more suitable process route for treating cemented carbide grinding waste is of great practical significance and application value. Summary of the Invention

[0007] To address the aforementioned issues, this technical solution proposes a method for preparing ammonium paratungstate from grinding waste. By optimizing the grinding process and chemical treatment steps, the potassium content in the grinding waste is reduced, ultimately producing ammonium paratungstate that meets the national grade zero standard (National Standard GBT10116-2007 requires that the potassium content of ammonium paratungstate products be less than or equal to 10 mg / kg).

[0008] This application discloses a method for preparing ammonium paratungstate from grinding waste, comprising the following steps:

[0009] S1. Obtain grinding waste, wherein the grinding waste contains tungsten carbide, and subject the grinding waste to acid leaching and calcination to obtain tungsten oxide;

[0010] S2. The tungsten oxide is ball-milled, wherein the ball-to-material ratio is 3:1 to 6:1, and the ball-milling time is 4 to 6 hours.

[0011] S3. Potassium removal reagent is used to remove potassium from the ball-milled tungsten oxide, wherein the potassium removal reagent contains hydrochloric acid and ethyl acetate;

[0012] S4. The potassium-removed tungsten oxide is subjected to ammonia dissolution crystallization to obtain ammonium paratungstate.

[0013] In the above technical solution, step S1 employs conventional acid leaching and roasting processes. Acid leaching separates tungsten and cobalt from the grinding waste, while simultaneously removing a small amount of potassium. Roasting converts the separated tungsten carbide into tungsten oxide, thus obtaining a precursor for ammonium paratungstate preparation and converting potassium into a soluble compound. In step S2, the grinding process is optimized by adjusting the ball milling parameters. Setting the ball-to-material ratio to 3:1 to 6:1 ensures sufficient contact between the milling media and the tungsten oxide. When the milling time is 4 to 6 hours, uniform and fine tungsten oxide particles are obtained, making them less prone to encapsulation in subsequent reactions, thereby reducing potassium contamination. Furthermore, prolonged milling prevents excessively fine particles, which could lead to low potassium removal efficiency in subsequent reactions. In step S3, the ball-milled tungsten oxide is treated with a potassium-removing reagent containing hydrochloric acid and ethyl acetate for the following reasons: 1. Hydrochloric acid provides an acidic environment, thereby dissolving soluble potassium-containing compounds in limestone and waste; 2. Tungsten oxide has a certain adsorption capacity on its surface under acidic conditions, attracting cations (such as potassium ions) in the solution. + It has adsorption capacity, and the carbonyl oxygen (C=O) of ethyl acetate has a lone pair of electrons, which may interact with K. + Forming a weak coordination bond, K + It can be "pulled out" from the solution or the surface of tungsten oxide to form soluble complexes (such as [K(CH3COOCH2CH3)). n ] + ), thereby promoting K + 3. Potassium-containing organic substances are present in cutting fluids or other impurities. These substances adhere to the surface of tungsten oxide and cannot be effectively treated with hydrochloric acid, but ethyl acetate can provide a good dissolution effect; 4. Ethyl acetate can also be used as an organic solvent to extract potassium-containing substances. + Complexes.

[0014] Furthermore, in step S1, the acid used during acid leaching includes hydrochloric acid or sulfuric acid;

[0015] Furthermore, the hydrogen ion concentration in the acid is 2-4 mol / L, and the liquid-to-solid ratio during acid leaching is 3:1-5:1 mL / g;

[0016] Furthermore, the roasting temperature is 600~700℃, and the roasting time is 1~2h.

[0017] Furthermore, in step S2, the diameter of the ball milling media used in the ball milling process is 5~10mm;

[0018] The grinding media of this diameter can provide suitable grinding force.

[0019] Furthermore, in step S2, the grinding media used in the ball milling includes steel balls;

[0020] Steel balls are selected as the grinding media, which have good wear resistance and grinding effect.

[0021] Furthermore, in step S2, the tungsten oxide is ball-milled using a ball mill, and the rotation speed of the ball mill is 280~400 rpm;

[0022] At this rotational speed, it can be ensured that the material is fully ground and mixed inside the ball mill.

[0023] Furthermore, in step S3, the concentration of hydrochloric acid is 5wt%~10wt%, and the concentration of ethyl acetate is 95wt%~98wt%.

[0024] A relatively dilute hydrochloric acid concentration can ensure the provision of an acidic environment to dissolve soluble potassium-containing compounds.

[0025] Furthermore, in step S3, the volume ratio of hydrochloric acid to ethyl acetate is 5:1 to 10:1.

[0026] Furthermore, in step S3, the liquid-to-solid ratio during potassium removal is 3:1 to 5:1 mL / g.

[0027] Furthermore, in step S3, the temperature during potassium removal is 40~80℃.

[0028] Furthermore, in step S3, the potassium removal time is 1-2 hours.

[0029] This method optimizes the grinding process by adjusting parameters such as ball milling time, type and size of grinding media, and ball milling speed, more effectively separating limestone and waste materials and reducing potassium contamination. Simultaneously, a specially formulated potassium removal agent is used to treat the grinding waste after ball milling to promote limestone dissolution, thereby removing potassium at the upstream stage. This method not only effectively reduces potassium content but also reduces energy consumption and environmental pollution, improving the quality and performance of tungsten products. In practical implementation, the above parameters can be appropriately adjusted and optimized based on the characteristics of different batches of materials and experimental results to achieve the best potassium content reduction effect. Furthermore, strict control of all parameters is crucial during operation to ensure the stability and reliability of the process.

[0030] This application proposes a method for preparing ammonium paratungstate from grinding waste, which produces the following beneficial effects: by adjusting the ball milling parameters to optimize the grinding process, uniform and fine tungsten oxide particles are obtained, thereby improving the efficiency of subsequent potassium removal; by configuring a specific potassium removal reagent to remove potassium at the front end, complex subsequent separation and purification steps are avoided, reducing production costs; by reducing the potassium content of tungsten oxide, the purity and quality of the final product are effectively improved; and it is applicable to the treatment of grinding waste under different environmental conditions, with strong environmental adaptability and flexibility. Detailed Implementation

[0031] The technical solutions in the embodiments will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0032] The technical solution proposed in this application includes the following steps:

[0033] S1. Obtain grinding waste, wherein the grinding waste contains tungsten carbide, and subject the grinding waste to acid leaching and calcination to obtain tungsten oxide;

[0034] Preferably, the grinding waste is acid-leached in hydrochloric acid or sulfuric acid with a hydrogen ion concentration of 2-4 mol / L, and the liquid-solid ratio during acid leaching is 3:1-5:1 mL / g, and then calcined at 600-700℃ for 1-2 hours to obtain tungsten oxide.

[0035] S2. The tungsten oxide is ball-milled, wherein the ball-to-material ratio is 3:1 to 6:1, and the ball-milling time is 4 to 6 hours.

[0036] Preferably, tungsten oxide is placed in a ball mill, and steel balls are used as the grinding media for ball milling. The diameter of the grinding media is 5~10mm, the ball-to-material ratio is 3:1~6:1, the speed of the ball mill is 280~400rpm, and the grinding time is 4~6h.

[0037] Specifically, the diameter of the ball milling media can be any one or any two of 5mm, 6mm, 7mm, 8mm, 9mm, and 10mm; the ball-to-material ratio can be any one or any two of 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, and 6:1; the rotational speed of the ball mill can be any one or any two of 280rpm, 300rpm, 320rpm, 340rpm, 360rpm, 380rpm, and 400rpm; and the ball milling time can be any one or any two of 4h, 4.5h, 5h, 5.5h, and 6h.

[0038] S3. Potassium removal reagent is used to remove potassium from the ball-milled tungsten oxide, wherein the potassium removal reagent contains hydrochloric acid and ethyl acetate;

[0039] Preferably, a potassium removal reagent is prepared using hydrochloric acid with a concentration of 5wt%~10wt% and ethyl acetate with a concentration of 95wt%~98wt%, wherein the volume ratio of hydrochloric acid to ethyl acetate is 5:1~10:1. The potassium removal reagent is used to remove potassium from the ball-milled tungsten oxide. The liquid-solid ratio during potassium removal is 3:1~5:1 mL / g, the temperature is 40~80℃, and the time is 1~2h. After potassium removal, solid-liquid separation is performed, followed by washing and drying to obtain potassium-removed tungsten oxide.

[0040] Specifically, the concentration of hydrochloric acid can be any one or any two of 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, and 10wt%, the concentration of ethyl acetate can be any one or any two of 95wt%, 96wt%, 97wt%, and 98wt%, the volume ratio of hydrochloric acid to ethyl acetate can be any one or any two of 5:1, 6:1, 7:1, 8:1, 9:1, and 10:1, the liquid-solid ratio for potassium removal can be any one or any two of 3:1mL / g, 3.5:1mL / g, 4:1mL / g, 4.5:1mL / g, and 5:1mL / g, and the temperature for potassium removal can be any one or any two of 40℃, 50℃, 60℃, 70℃, and 80℃.

[0041] S4. The potassium-removed tungsten oxide is subjected to ammonia dissolution crystallization to obtain ammonium paratungstate.

[0042] The same batch of grinding waste was used in all embodiments and comparative examples of this application. The grinding waste was acid-leached in hydrochloric acid with a hydrogen ion concentration of 2 mol / L, with a liquid-to-solid ratio of 3:1 mL / g. It was then calcined at 700°C for 2 hours to obtain tungsten oxide, which was then subjected to further processing. The technical solution of this application will be further described below with reference to specific embodiments.

[0043] Example 1

[0044] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, using steel balls (10mm diameter) as the milling medium. The ball-to-material ratio was 3:1, the mill speed was 300rpm, and the milling time was 4 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate (volume ratio 5:1). 1500mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0045] Tests showed that the potassium content in the potassium-removed tungsten oxide was 6 ppm, and the potassium content in the prepared ammonium paratungstate was 7 ppm.

[0046] Example 2

[0047] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, and ball milling was performed using steel balls (10mm diameter, ball-to-material ratio 3:1) at a speed of 300rpm for 6 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate (volume ratio 5:1). 1500mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0048] Tests showed that the potassium content in the potassium-removed tungsten oxide was 4 ppm, and the potassium content in the prepared ammonium paratungstate was 5 ppm.

[0049] Example 3

[0050] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill and ball-milled using steel balls (10mm diameter, 6:1 ball-to-material ratio) at 300rpm for 4 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate (volume ratio 5:1). 1500mL of this reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0051] Tests showed that the potassium content in the potassium-removed tungsten oxide was 2 ppm, and the potassium content in the prepared ammonium paratungstate was 3 ppm.

[0052] Example 4

[0053] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, using steel balls (10mm diameter) as the milling medium. The ball-to-material ratio was 3:1, the mill speed was 300rpm, and the milling time was 4 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate (volume ratio 5:1). 2500mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0054] Tests showed that the potassium content in the potassium-removed tungsten oxide was 1 ppm, and the potassium content in the prepared ammonium paratungstate was also 1 ppm.

[0055] Example 5

[0056] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, using steel balls (5mm diameter) as the milling medium. The ball-to-material ratio was 3:1, the mill speed was 400rpm, and the milling time was 5h. A potassium removal reagent was prepared using 5wt% hydrochloric acid and 98wt% ethyl acetate (volume ratio 8:1). 2000mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 60℃ for 1h. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0057] Tests showed that the potassium content in the potassium-removed tungsten oxide was 4 ppm, and the potassium content in the prepared ammonium paratungstate was 5 ppm.

[0058] Example 6

[0059] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill and ball-milled using steel balls (8mm diameter, ball-to-material ratio 4:1) at 280rpm for 4 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate (volume ratio 10:1). 1500mL of this reagent was used to remove potassium from the ball-milled tungsten oxide at 40℃ for 2 hours. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0060] Tests showed that the potassium content in the potassium-removed tungsten oxide was 6 ppm, and the potassium content in the prepared ammonium paratungstate was 7 ppm.

[0061] Comparative Example 1

[0062] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, and ball milling was performed using steel balls with a diameter of 10mm, a ball-to-material ratio of 3:1, a ball mill speed of 300rpm, and a milling time of 2 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate, with a volume ratio of hydrochloric acid to ethyl acetate of 5:1. 1500mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0063] Tests showed that the potassium content in the tungsten oxide after potassium removal was 26 ppm, and the potassium content in the prepared ammonium paratungstate was 45 ppm.

[0064] Comparative Example 2

[0065] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, using steel balls (10mm diameter) as the milling medium. The ball-to-material ratio was 3:1, the mill speed was 300rpm, and the milling time was 8 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate (volume ratio 5:1). 1500mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0066] Tests showed that the potassium content in the potassium-removed tungsten oxide was 41 ppm, and the potassium content in the prepared ammonium paratungstate was 67 ppm.

[0067] Comparative Example 3

[0068] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, using steel balls (10mm diameter) as the milling medium. The ball-to-material ratio was 2:1, the mill speed was 300rpm, and the milling time was 6 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate (volume ratio 5:1). 1500mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0069] Tests showed that the potassium content in the tungsten oxide after potassium removal was 28 ppm, and the potassium content in the prepared ammonium paratungstate was 49 ppm.

[0070] Comparative Example 4

[0071] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, and ball milling was performed using steel balls (10mm diameter, ball-to-material ratio 7:1) at a speed of 300rpm for 6 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethyl acetate (volume ratio 5:1). 1500mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0072] Tests showed that the potassium content in the potassium-removed tungsten oxide was 34 ppm, and the potassium content in the prepared ammonium paratungstate was 54 ppm.

[0073] Comparative Example 5

[0074] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill and ball-milled using steel balls with a diameter of 10mm, a ball-to-material ratio of 3:1, a ball mill speed of 300rpm, and a ball milling time of 4h. Potassium was removed from the ball-milled tungsten oxide using 1500mL of 10wt% hydrochloric acid at a temperature of 80℃ for 1h. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then crystallized by ammonia dissolution to obtain ammonium paratungstate.

[0075] Tests showed that the potassium content in the tungsten oxide after potassium removal was 23 ppm, and the potassium content in the prepared ammonium paratungstate was 43 ppm.

[0076] Comparative Example 6

[0077] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill and ball-milled using steel balls with a diameter of 10mm, a ball-to-material ratio of 3:1, a ball mill speed of 300rpm, and a grinding time of 4h. Potassium was removed from the ball-milled tungsten oxide using 1500mL of 95wt% ethyl acetate at 80℃ for 1h. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then crystallized by ammonia dissolution to obtain ammonium paratungstate.

[0078] Tests showed that the potassium content in the potassium-removed tungsten oxide was 38 ppm, and the potassium content in the prepared ammonium paratungstate was 56 ppm.

[0079] Comparative Example 7

[0080] Grinding waste was acid-leached and roasted to obtain tungsten oxide. 500g of tungsten oxide was placed in a ball mill, using steel balls (10mm diameter) as the milling medium. The ball-to-material ratio was 3:1, the mill speed was 300rpm, and the milling time was 6 hours. A potassium removal reagent was prepared using 10wt% hydrochloric acid and 95wt% ethanol (volume ratio 5:1). 1500mL of the potassium removal reagent was used to remove potassium from the ball-milled tungsten oxide at 80℃ for 1 hour. After potassium removal, solid-liquid separation, washing, and drying were performed to obtain potassium-removed tungsten oxide. The potassium-removed tungsten oxide was then subjected to ammonia crystallization to obtain ammonium paratungstate.

[0081] Tests showed that the potassium content in the potassium-removed tungsten oxide was 24 ppm, and the potassium content in the prepared ammonium paratungstate was 30 ppm.

[0082] The comparative examples show that too much or too little ball-to-material ratio during ball milling, too long or too short ball milling time, and failure to use hydrochloric acid and ethyl acetate simultaneously to prepare the potassium removal reagent will all lead to excessive potassium content in the prepared tungsten oxide and ammonium paratungstate. Therefore, by adjusting the experimental parameters according to the technical solution provided by this invention, the final potassium removal effect can meet the standard.

[0083] This application proposes a method for preparing ammonium paratungstate from grinding waste, which produces the following beneficial effects: by adjusting the ball milling parameters to optimize the grinding process, uniform and fine tungsten oxide particles are obtained, thereby improving the efficiency of subsequent potassium removal; by configuring a specific potassium removal reagent to remove potassium at the front end, complex subsequent separation and purification steps are avoided, reducing production costs; by reducing the potassium content of tungsten oxide, the purity and quality of the final product are effectively improved; and it is applicable to the treatment of grinding waste under different environmental conditions, with strong environmental adaptability and flexibility.

[0084] The above description is only a preferred embodiment of this application and does not limit the patent scope of this application. All equivalent structural transformations made using the content of this application's specification under the inventive concept of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A method for preparing ammonium paratungstate from grinding waste, characterized in that, Includes the following steps: S1. Obtain grinding waste, wherein the grinding waste contains tungsten carbide, and subject the grinding waste to acid leaching and calcination to obtain tungsten oxide; S2. The tungsten oxide is ball-milled, wherein the ball-to-material ratio is 3:1 to 6:1, and the ball-milling time is 4 to 6 hours. S3. Potassium removal reagent is used to remove potassium from the ball-milled tungsten oxide, wherein the potassium removal reagent contains hydrochloric acid and ethyl acetate; S4. The potassium-removed tungsten oxide is subjected to ammonia dissolution crystallization to obtain ammonium paratungstate.

2. The method for preparing ammonium paratungstate from grinding waste according to claim 1, characterized in that, In step S1, the acid used during acid leaching includes hydrochloric acid or sulfuric acid.

3. The method for preparing ammonium paratungstate from grinding waste according to claim 1, characterized in that, In step S2, the diameter of the ball milling media used in the ball milling process is 5~10mm.

4. The method for preparing ammonium paratungstate from grinding waste according to claim 1, characterized in that, In step S2, the grinding media used in the ball milling includes steel balls.

5. The method for preparing ammonium paratungstate from grinding waste according to claim 1, characterized in that, In step S2, the tungsten oxide is ball-milled using a ball mill at a speed of 280-400 rpm.

6. The method for preparing ammonium paratungstate from grinding waste according to claim 1, characterized in that, In step S3, the concentration of hydrochloric acid is 5wt%~10wt%, and the concentration of ethyl acetate is 95wt%~98wt%.

7. The method for preparing ammonium paratungstate from grinding waste according to claim 6, characterized in that, In step S3, the volume ratio of hydrochloric acid to ethyl acetate is 5:1 to 10:

1.

8. The method for preparing ammonium paratungstate from grinding waste according to claim 1, characterized in that, In step S3, the liquid-to-solid ratio during potassium removal is 3:1 to 5:1 mL / g.

9. The method for preparing ammonium paratungstate from grinding waste according to claim 8, characterized in that, In step S3, the temperature during potassium removal is 40~80℃.

10. The method for preparing ammonium paratungstate from grinding waste according to claim 9, characterized in that, In step S3, the potassium removal time is 1-2 hours.