A method for removing tungsten from raffinate

Abstract

The application provides a method for removing tungsten in raffinate, and belongs to the technical field of non-ferrous metal extraction. The method for removing tungsten in raffinate comprises the following steps: mixing raffinate with an adsorbent and / or a precipitant to obtain a mixed solution; under stirring, reacting at 25 DEG C to 60 DEG C for 0.5 hours to 3 hours to obtain a reaction solution; and performing solid-liquid separation on the reaction solution to obtain raffinate after tungsten removal and a tungsten-rich solid phase. The method for removing tungsten in raffinate can realize deep removal of tungsten in raffinate, and can reduce cost and pollution.

Description

Technical Field

[0001] This invention relates to the field of non-ferrous metal extraction technology, and in particular to a method for removing tungsten from raffinate. Background Technology

[0002] Tungsten is a metallic element with the chemical symbol W, atomic number 74, relative atomic mass 183.85, atomic radius 137 picometers, and density 19.35 g / cm³. It belongs to Group VIB of the sixth period (second longest period) of the periodic table. Tungsten primarily exists in nature as a hexavalent cation. A typical rare metal, tungsten has important applications and is a crucial component of modern high-tech materials. Electron optical materials, special alloys, novel functional materials, and organometallic compounds all require tungsten with unique properties. Although the amount of tungsten used in these fields is not large, it is essential and indispensable. Therefore, it is widely used in modern communication technology, electronic computers, aerospace development, medicine and health, photosensitive materials, optoelectronic materials, energy materials, and catalyst materials.

[0003] In the solvent extraction process of tungsten hydrometallurgy, a certain amount of tungsten element usually remains in the raffinate. Direct discharge would lead to the loss of tungsten resources and environmental pressure; direct reuse would result in a decrease in the purity of subsequent products. Traditional methods for removing tungsten from raffinate, such as ion exchange and precipitation, suffer from limited adsorption capacity, high reagent consumption, large slag volume, and difficulty in tungsten recovery. Therefore, developing an efficient, economical, and environmentally friendly method for removing tungsten from raffinate is of great significance for improving the utilization rate of tungsten resources and ensuring the stability of subsequent processes. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a method for removing tungsten from the raffinate, aiming to achieve deep removal of tungsten from the raffinate and reduce costs and pollution.

[0005] To achieve the above-mentioned technical objectives, a first aspect of the present invention provides a method for removing tungsten from raffinate, comprising the following steps: mixing the raffinate with an adsorbent and / or a precipitant to obtain a mixed solution; reacting the mixture at 25°C to 60°C for 0.5 hours to 3 hours under stirring conditions to obtain a reaction solution; and separating the reaction solution into solid and liquid phases to obtain a tungsten-removed raffinate and a tungsten-rich solid phase.

[0006] In some embodiments, the raffinate is a raffinate obtained by solvent extraction in tungsten hydrometallurgy; and / or, the concentration of tungsten in the raffinate is 0.1 g / L to 1.0 g / L.

[0007] In some embodiments, the pH value of the reaction is 8 to 9.

[0008] In some embodiments, the precipitant comprises a complex iron salt.

[0009] In some embodiments, the composite iron salt comprises a composite aluminum-iron.

[0010] In some embodiments, the mass ratio of the composite iron salt to the volume of the raffinate is (0.3~1) g: 1 L.

[0011] In some embodiments, the adsorbent comprises a chelating resin.

[0012] In some embodiments, the chelating resin includes one or more of D403 chelating resin, morpholine chelating resin, and aminophosphonic acid resin.

[0013] In some embodiments, the mass ratio of the chelating resin to the raffinate is (0.5~1.5):10.

[0014] In some embodiments, after the step of separating the reaction liquid into solid and liquid phases to obtain raffinate and tungsten-rich solid phase, the method further includes: washing, desorbing and / or leaching the tungsten-rich solid phase to obtain a high-concentration tungsten solution for tungsten recovery.

[0015] Compared with the prior art, the beneficial effects of the present invention include: The method for removing tungsten from raffinate provided by this invention, under stirring and at 25℃~60℃, selectively adsorbs tungsten or selectively precipitates tungsten, taking into account the characteristics of tungsten in the raffinate. This achieves deep removal of tungsten from the raffinate, reducing the residual tungsten concentration to below 0.01 g / L, with high tungsten removal efficiency. Furthermore, the tungsten-rich solid phase can be efficiently desorbed / leached, enabling the recovery and utilization of tungsten resources and avoiding resource waste. The method requires less reagent and produces less residue, significantly reducing wastewater and solid waste treatment costs and is environmentally friendly. Attached Figure Description

[0016] Figure 1 This is a schematic flowchart of a method for removing tungsten from raffinate provided in an embodiment of the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0018] A first aspect of the present invention provides a method for removing tungsten from raffinate; see [link to relevant documentation]. Figure 1 The method for removing tungsten from the raffinate includes the following steps: S1. Mix the raffinate with the adsorbent and / or precipitant to obtain a mixed solution.

[0019] In some embodiments, the raffinate is the raffinate obtained from the solvent extraction process of tungsten hydrometallurgy. Hydrometallurgy is a process in which metallic mineral raw materials are chemically treated or extracted with organic solvents in an aqueous solution of an acidic or alkaline medium to separate impurities and extract metals and their compounds. As an example, in tungsten hydrometallurgy, after pretreatment, tungsten smelting slag is acid-leached, and after pressure filtration, the filtrate contains tungsten, manganese, iron, and calcium. Iron powder is added to the filtrate, and after stirring and settling, it is filtered. The filter residue is a silver concentrate. An extractant is used to extract iron and tungsten from the filtrate to further improve the quality of the obtained product. Tungsten hydrometallurgy is an important method for producing tungsten. In this method, during the extraction operation, a portion of cobalt element remains in the raffinate. Removing or reusing the cobalt element is in line with the requirements of sustainable development.

[0020] In some embodiments, the concentration of tungsten in the raffinate is 0.1 g / L to 1.0 g / L. That is, each liter of raffinate contains 0.1 to 1.0 g of cobalt. As an example, the concentration of tungsten in the raffinate can be 0.1 g / L, 0.2 g / L, 0.3 g / L, 0.4 g / L, 0.5 g / L, 0.6 g / L, 0.7 g / L, 0.8 g / L, 0.9 g / L, 1.0 g / L, or any combination of two of the above values. Thus, by controlling the cobalt content in the raffinate within the above range, the cobalt removal rate is higher when adapted to the method of the present invention.

[0021] In some embodiments, the precipitant comprises a composite iron salt. A composite iron salt is a salt containing iron and other metallic elements. Composite iron salts can selectively and directionally adsorb cobalt, exhibiting high adsorption efficiency and minimal release of cobalt after adsorption. This enables deep removal of tungsten from the raffinate, reducing the residual tungsten concentration to below 0.01 g / L, demonstrating high tungsten removal efficiency.

[0022] In some embodiments, the composite iron salt comprises a composite aluminum-iron. Experiments show that the above-mentioned composite iron salt can further achieve deep removal of tungsten from the raffinate, reducing the residual tungsten concentration to below 0.01 g / L, with high tungsten removal efficiency.

[0023] It is understandable that the aforementioned composite iron salts can be purchased or prepared at home.

[0024] In some embodiments, composite aluminum-iron is a coagulant prepared by coagulating and hydrolyzing aluminum salts and iron salts, and then adding elemental iron ions or ferric oxide and other iron-containing compounds.

[0025] In some embodiments, the mass ratio of the composite iron salt to the volume of the raffinate is (0.3~1) g:1 L. As an example, the mass ratio of the composite iron salt to the raffinate can be 0.3 g:1 L, 0.4 g:1 L, 0.5 g:1 L, 0.6 g:1 L, 0.7 g:1 L, 0.8 g:1 L, 0.9 g:1 L, 1 g:1 L, or any range of two of these values. Therefore, controlling the mass ratio within the above range is sufficient to transfer the total cobalt element from the liquid phase to the solid phase of the raffinate, without causing excessive waste due to excessive composite iron salt content. Furthermore, adding too much composite iron salt would make subsequent cobalt element recovery and enrichment more difficult.

[0026] In some embodiments, the adsorbent comprises a chelating resin. A chelating resin is a cross-linked functional polymer material capable of forming multi-coordinate complexes with metal ions. The mechanism by which chelating resins adsorb metal ions involves the coordination reaction between functional atoms on the resin and the metal ions, forming a stable structure similar to a small-molecule chelate. Therefore, for cobalt, using chelating resin adsorption further facilitates the transfer of as much cobalt as possible from the liquid phase to the solid phase, achieving deep removal of cobalt and reducing cost and pollution.

[0027] In some embodiments, the chelating resin includes one or more of D403 chelating resin, morpholine chelating resin, and aminophosphonic acid resin. Experiments show that the above-mentioned chelating resin can further achieve deep removal of tungsten from the raffinate, reducing the residual tungsten concentration to below 0.01 g / L, demonstrating high tungsten removal efficiency.

[0028] It is understandable that the chelating resins mentioned above can be purchased or prepared at home.

[0029] In some embodiments, the mass ratio of the chelating resin to the raffinate is (0.5~1.5):10. As an example, the mass ratio of the chelating resin to the raffinate can be 0.5:10, 0.7:10, 0.9:10, 1:10, 1.2:10, 1.4:10, 1.5:10, or any range of two of the above values. This ensures that the total cobalt in the raffinate is transferred from the liquid phase to the solid phase, preventing the release of cobalt after the transfer, while also preventing excessive chelating resin content that would lead to waste, and avoiding excessive chelating resin that would make subsequent cobalt recovery and enrichment more difficult.

[0030] S2. Under stirring conditions, react at 25℃~60℃ for 0.5 hours to 3 hours to obtain the reaction solution.

[0031] As an example, the reaction temperature can be 25℃, 30℃, 35℃, 40℃, 45℃, 50℃, 55℃, 60℃ or any two of the above values, and the reaction time can be 0.5 hours, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours or any two of the above values. Thus, the process conditions are mild, no high temperature and high pressure are required, the operation is simple, it is easy to connect with existing extraction processes, and deep removal of cobalt can be achieved.

[0032] In some embodiments, the stirring can be mechanical stirring. The present invention does not limit the stirring speed. As an example, the stirring speed is 200 rpm to 500 rpm.

[0033] In some embodiments, the pH value of the reaction is 8 to 9. For example, the pH value of the reaction can be 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9, or any combination of two of these values. Therefore, within the aforementioned pH range, it is further beneficial for the adsorbent to fully adsorb cobalt elements in the raffinate, or for the precipitant to fully react with cobalt elements, allowing as much cobalt as possible to transfer from the liquid phase to the solid phase, achieving deep removal of cobalt elements, and reducing costs and pollution.

[0034] S3. Separate the reaction solution into solid and liquid phases to obtain raffinate after tungsten removal and tungsten-rich solid phase.

[0035] Specifically, filtration can be a method for solid-liquid separation.

[0036] In some embodiments, after step S3, the method for removing tungsten from the raffinate further includes: S4. The tungsten-rich solid phase is washed, desorbed and / or leached to obtain a high-concentration tungsten solution for tungsten recovery.

[0037] Specifically, when an adsorbent is used, the solid phase undergoes desorption; when a precipitant is used, the solid phase undergoes leaching.

[0038] It is understood that desorption can be performed using methods commonly used in the field, such as desorption using an alkaline solution; leaching can also be performed using methods commonly used in the field, such as leaching with sodium hydroxide solution.

[0039] In some embodiments, the tungsten concentration in the raffinate after tungsten removal is reduced to a compliant level, allowing for direct reuse or discharge.

[0040] In summary, the method for removing tungsten from raffinate provided by this invention, under stirring and at 25℃~60℃, utilizes the characteristics of tungsten in the raffinate by adding an adsorbent that can selectively adsorb tungsten or a precipitant that can selectively precipitate tungsten. This achieves deep removal of tungsten from the raffinate, reducing the residual tungsten concentration to below 0.01 g / L, demonstrating high tungsten removal efficiency. Furthermore, the tungsten-rich solid phase can be efficiently desorbed / leached, enabling the recovery and utilization of tungsten resources and avoiding resource waste. The method also requires less reagent and produces less residue, significantly reducing wastewater and solid waste treatment costs and is environmentally friendly.

[0041] Furthermore, the method for removing tungsten from the raffinate provided by this invention has mild process conditions, does not require high temperature and high pressure, is easy to operate, and is easy to connect with the existing solvent extraction process of tungsten hydrometallurgy; it has low processing cost, significant economic benefits, and is suitable for large-scale industrial application.

[0042] The following are some specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0043] Example 1 Treatment conditions for raffinate (tungsten concentration 0.5 g / L): Use composite iron salt precipitant (composite aluminum iron), dosage 0.5 g / L (composite iron salt mass to raffinate volume ratio 0.5 g: 1 L), temperature 40℃, pH 8.3, stirring reaction for 1.5 hours. Results: Tungsten residual concentration in raffinate decreased to 0.008 g / L, tungsten removal rate ≥98.4%, tungsten grade in tungsten-rich precipitate ≥35%.

[0044] The method for testing tungsten concentration is ICP (Inductively Coupled Plasma Spectrometry). Tungsten removal rate = (Initial tungsten concentration - Final raffinate residual concentration) / Initial tungsten concentration.

[0045] Test method for tungsten grade in tungsten-rich precipitates: Refer to standard GB / T 6150.1-2023.

[0046] Example 2 Treatment conditions for high-concentration raffinate (tungsten concentration 1.0 g / L): chelating resin (D403 chelating resin) was used for adsorption, liquid-to-solid ratio was 10:1 (mass ratio of chelating resin to raffinate was 1:10), temperature was 30℃, pH was 9, and adsorption time was 2 hours. Results: The residual tungsten concentration in the raffinate decreased to 0.005 g / L, the tungsten removal rate was ≥99.5%, and the tungsten solution concentration after resin desorption was ≥20 g / L.

[0047] The remaining embodiments and comparative examples differ from Embodiment 2 in that, as shown in Table 1.

[0048] Table 1

[0049] The ion exchange method used in Comparative Example 5 is specifically operated as follows: Treatment conditions for high-concentration raffinate (tungsten concentration 1.0 g / L): neutralize with sulfuric acid to pH 5 as pre-exchange solution. Adsorb tungsten in the pre-exchange solution using macroporous weakly basic anion exchange resin at 30℃ for 4 hours.

[0050] The tungsten removal rates of the methods in the above embodiments and comparative examples are shown in Table 2.

[0051] Table 2

[0052] As shown in Table 2, the methods for removing tungsten from the raffinate according to Examples 1 to 6 of this invention can achieve deep removal of tungsten from the raffinate, reducing the residual tungsten concentration to below 0.01 g / L, demonstrating high tungsten removal efficiency. The parameters of Comparative Examples 1 to 4 are not within the scope of this invention. Comparative Example 5 uses a traditional ion exchange method for tungsten removal, resulting in a significantly reduced tungsten removal efficiency. Therefore, the methods of this invention can achieve deep removal of tungsten from the raffinate.

[0053] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for removing tungsten from raffinate, characterized in that, Includes the following steps: The raffinate is mixed with an adsorbent and / or a precipitant to obtain a mixture; Under stirring conditions, the reaction was carried out at 25℃~60℃ for 0.5 hours~3 hours to obtain a reaction solution; The reaction solution is separated into solid and liquid phases to obtain raffinate after tungsten removal and tungsten-rich solid phase.

2. The method for removing tungsten from raffinate according to claim 1, characterized in that, The raffinate is the raffinate obtained from the solvent extraction process in tungsten hydrometallurgy; and / or, The concentration of tungsten in the raffinate is 0.1 g / L to 1.0 g / L.

3. The method for removing tungsten from the raffinate according to claim 1, characterized in that, The pH value of the reaction is 8-9.

4. The method for removing tungsten from raffinate according to claim 1, characterized in that, The precipitant includes a complex iron salt.

5. The method for removing tungsten from the raffinate according to claim 4, characterized in that, The composite iron salt includes composite aluminum iron.

6. The method for removing tungsten from the raffinate according to claim 4 or 5, characterized in that, The mass ratio of the composite iron salt to the volume of the raffinate is (0.3~1) g: 1 L.

7. The method for removing tungsten from raffinate according to claim 1, characterized in that, The adsorbent includes a chelating resin.

8. The method for removing tungsten from raffinate according to claim 7, characterized in that, The chelating resin includes one or more of D403 chelating resin, morpholine chelating resin, and aminophosphonic acid resin.

9. The method for removing tungsten from the raffinate according to claim 7 or 8, characterized in that, The mass ratio of the chelating resin to the raffinate is (0.5~1.5):

10.

10. The method for removing tungsten from raffinate according to claim 1, characterized in that, After separating the reaction solution into solid and liquid phases to obtain the raffinate after tungsten removal and the tungsten-rich solid phase, the process further includes: The tungsten-rich solid phase is washed, desorbed, and / or leached to obtain a high-concentration tungsten solution for tungsten recovery.

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