Extraction and separation method of tantalum-niobium ore

Abstract

The invention provides an extraction and separation method of tantalum-niobium ore, and relates to the technical field of tantalum-niobium ore decomposition. The tantalum-niobium ore extraction and separation method comprises the steps that target tantalum-niobium ore is taken and added into an ammonium bifluoride solution to be heated and decomposed, and decomposition liquid is obtained after solid-liquid separation; and carrying out gradient elution on the decomposition liquid by taking ion exchange resin as a stationary phase and hydrochloric acid as a mobile phase to respectively obtain fluoroniobic acid, fluotantalic acid and residual liquid. The ammonium bifluoride solution is adopted to replace traditional high-concentration acid, so that the environmental pollution is reduced, the extraction efficiency and the resource recovery rate are improved, and the resource waste is reduced. Meanwhile, equipment corrosion is reduced, the service life of equipment is prolonged, cost is reduced, and economic benefits are improved. The gradient elution technology of the ion exchange resin simplifies the process and improves the product quality.

Description

Technical Field

[0001] The present invention relates to the technical field of tantalum-niobium ore decomposition, and in particular to a method for extracting and separating tantalum-niobium ore. Background Art

[0002] Tantalum-niobium hydrometallurgy is the key link in the extraction and purification of tantalum-niobium metals. The products produced by this technology are widely used in modern electronics and aviation industries. The main function of this metallurgical process is to convert the valuable metal elements tantalum-niobium in tantalum-niobium ore into metal compounds through chemical methods for further processing.

[0003] At present, the hydrometallurgical technology of tantalum and niobium at home and abroad generally uses high-concentration hydrofluoric acid or a mixture of hydrofluoric acid and concentrated sulfuric acid to decompose tantalum and niobium ores. Although this method has achieved the extraction of tantalum and niobium to a certain extent, its high acidity and strong corrosiveness have brought environmental harm and serious equipment loss. In addition, for every ton of tantalum and niobium ore processed, an average of about 4 tons of hydrofluoric acid is consumed, and for low-grade ores, this number is as high as 6 to 8 tons.

[0004] A major problem with the existing technology is the heavy environmental burden. The residual acid produced during the decomposition process is difficult to completely recover and is ultimately converted into calcium sulfate or fluorite residue in the waste liquid. For every ton of tantalum-niobium ore processed, about 10 to 15 tons of fluorine-containing waste residue will be produced. In addition, a large amount of fluorine-containing waste gas will be produced during the decomposition process, and its fluorine content accounts for about 10% of the amount of hydrofluoric acid used. These waste gases and waste residues pose a serious threat to the ecological environment.

[0005] In addition, low resource utilization is also a prominent problem. With the surge in demand for capacitor-grade tantalum powder and tantalum alloys, the supply of high-grade hard rock ore has been unable to meet market demand. Most domestic tantalum-niobium ores are of low grade, finely embedded particle size, and complex composition, making them difficult to decompose. After being treated with the current hydrofluoric acid-sulfuric acid method, the decomposition rate is only about 85%, which means that a considerable portion of resources have not been effectively utilized, resulting in serious waste of resources.

[0006] In summary, the existing tantalum-niobium hydrometallurgical technology has significant defects in resource consumption, environmental pollution and resource utilization. These defects not only limit the sustainable supply of tantalum-niobium metals, but also pose potential risks to the environment and human health. Therefore, the development of more environmentally friendly and efficient tantalum-niobium extraction technology has become an urgent need for the development of the industry.

[0007] In view of this, the present invention is proposed. Summary of the invention

[0008] The object of the present invention is to provide a method for extracting and separating tantalum-niobium ore, which uses ammonium bifluoride solution for heating and decomposition, and uses ion exchange resin for separation, thereby reducing the cost of extraction and separation and being more environmentally friendly.

[0009] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0010] In a first aspect, the present invention provides a method for extracting and separating tantalum-niobium ore, comprising:

[0011] The target tantalum-niobium ore is added into an ammonium bifluoride solution for heating and decomposition, and a decomposition liquid is obtained after solid-liquid separation;

[0012] The decomposition liquid is subjected to gradient elution using ion exchange resin as the stationary phase and hydrochloric acid as the mobile phase to obtain fluoroniobic acid, fluorotantalic acid and residual liquid respectively.

[0013] In an optional embodiment, the ammonium bifluoride solution is an ammonium bifluoride solution with a concentration of 400 g / L to 450 g / L.

[0014] In an optional embodiment, the target tantalum-niobium ore is added to an ammonium bifluoride solution for heating and decomposition, and a decomposed liquid is obtained after solid-liquid separation, comprising:

[0015] preparing the ammonium bifluoride solution;

[0016] Under the condition of heating the ammonium bifluoride solution, mixing the target tantalite niobium ore with the ammonium bifluoride solution, and subjecting the mixture to a stirring and dissolving process to obtain a dissolved mixture;

[0017] The dissolved mixture is subjected to solid-liquid separation to obtain the decomposed liquid.

[0018] In an optional embodiment, the heating temperature of the ammonium bifluoride is 70°C to 80°C.

[0019] In an optional embodiment, the stirring and dissolving treatment is carried out for 8 to 10 hours.

[0020] In an optional embodiment, the pH of the dissolved mixture is 4-5; and / or the liquid-to-solid ratio of the target tantalum-niobium ore and the ammonium bifluoride solution when mixed is 10:1.

[0021] In an optional embodiment, the decomposition liquid is subjected to gradient elution using an ion exchange resin as a stationary phase and hydrochloric acid as a mobile phase to obtain fluoronioic acid, fluorotantalic acid and a residual liquid, respectively, comprising:

[0022] After the ion exchange resin is loaded into the chromatography column, it is eluted with deionized water;

[0023] Adding the decomposition solution to a chromatography column for loading;

[0024] The chromatography column is gradient eluted using aqueous hydrochloric acid solutions of different concentrations, and fluoroniobic acid, fluorotantalic acid and residual liquid are collected respectively.

[0025] In an optional embodiment, the step of gradient eluting the chromatography column using aqueous hydrochloric acid solutions of different concentrations comprises:

[0026] Sequentially using a hydrochloric acid aqueous solution of a first concentration, a hydrochloric acid aqueous solution of a second concentration, and a hydrochloric acid aqueous solution of a third concentration as mobile phases to elute the chromatography column;

[0027] Among them, the third concentration>the second concentration>the first concentration;

[0028] In an optional embodiment, the first concentration is 0.1 mol / L to 1 mol / L;

[0029] In an optional embodiment, the second concentration is 2 mol / L to 3 mol / L;

[0030] In an optional embodiment, the third concentration is 4 mol / L to 6 mol / L.

[0031] In an optional embodiment, different concentrations of aqueous hydrochloric acid solutions have different elution rates;

[0032] In an optional embodiment, the elution rate of the hydrochloric acid aqueous solution of the first concentration is 2 BV / h;

[0033] In an optional embodiment, the elution rate of the second concentration of the hydrochloric acid aqueous solution is 5 BV / h;

[0034] In an optional embodiment, the elution rate of the third concentration of the aqueous hydrochloric acid solution is 7 BV / h.

[0035] In an optional embodiment, during the process of adding the decomposition solution into the chromatography column, the flow rate is controlled at 5 BV / h to 7 BV / h.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] The extraction and separation method of tantalum-niobium ore provided by the present invention not only reduces the pollution to the environment and the emission of fluorine-containing waste gas and waste residue by using ammonium bifluoride solution instead of traditional high-concentration hydrofluoric acid or hydrofluoric acid-concentrated sulfuric acid mixed acid, but also improves the extraction efficiency of tantalum-niobium elements and the recovery rate of resources, and reduces the waste of resources. At the same time, the lower corrosiveness of ammonium bifluoride enhances the safety of operation, reduces equipment corrosion, prolongs the service life of equipment, and helps to reduce production costs and improve economic benefits. In addition, the gradient elution of ion exchange resin can accurately control the elution conditions, simplify the process flow, improve product quality, make the technology more efficient and flexible, and suitable for tantalum-niobium ores of different grades and compositions. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 It is a schematic diagram of the process of extracting and separating tantalum-niobium ore in the embodiment of the present application. DETAILED DESCRIPTION

[0040] The embodiments of the present invention will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. If no specific conditions are specified in the examples, the conditions are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be obtained commercially.

[0041] refer to Figure 1 In the embodiment of the present application, a method for extracting and separating tantalum-niobium ore is provided, comprising:

[0042] Step S1, taking the target tantalum-niobium ore and adding it into an ammonium bifluoride solution for heating and decomposition, and obtaining a decomposed liquid after solid-liquid separation.

[0043] The target tantalum-niobium ore mentioned above is the tantalum-niobium ore that needs to be extracted and separated.

[0044] Specifically, the tantalum-niobium ore may be a tantalum-niobium ore that has been pre-treated, that is, before step S1, the following steps are also included:

[0045] The raw material mineral is pre-treated; the pre-treatment includes:

[0046] The raw material mineral is processed through a 100-mesh sieve to obtain the target tantalum-niobium ore.

[0047] The above steps involve mixing tantalum-niobium ore with ammonium bifluoride solution and heating at a certain temperature to promote the chemical reaction between tantalum and niobium in the tantalum-niobium ore and the ammonium bifluoride to achieve the decomposition of tantalum-niobium elements.

[0048] Among them, heating treatment increases the reaction temperature to accelerate the decomposition process of tantalum and niobium in tantalum-niobium ore. Solid-liquid separation separates the solid residue after the reaction from the liquid decomposition liquid through filtration or other separation techniques.

[0049] The above decomposition liquid contains dissolved tantalum and niobium compounds, mainly fluoroniobic acid and fluorotantalic acid.

[0050] As described above, compared with the traditional hydrofluoric acid decomposition, the ammonium bifluoride decomposition produces less waste residue and waste gas and has less impact on the environment.

[0051] In this embodiment, the ammonium bifluoride solution used is an aqueous solution of ammonium bifluoride. The ammonium bifluoride solution is used as a decomposition agent, which has the following advantages:

[0052] First, compared with high-concentration hydrofluoric acid (HF), ammonium bifluoride (NH4HF2) is less corrosive, has less impact on the environment and equipment, and produces less fluorine-containing waste gas and waste slag; secondly, ammonium bifluoride can effectively react with tantalum and niobium in tantalum-niobium ore; and, the cost of ammonium bifluoride is relatively low, and the consumption in the extraction process is small, which helps to reduce the overall production cost.

[0053] In terms of chemical reaction, ammonium bifluoride reacts with tantalum and niobium in tantalite to generate fluoroniobate (NbF5) and fluorotantalate (TaF5), while releasing ammonium fluoride (NH4F). The specific chemical reaction can be expressed as follows:

[0054] (1) Reaction for niobium: Nb2O5+10NH4HF2→2NbF5+10NH4F+5H2O;

[0055] (2) Reaction of tantalum: Ta2O5+10NH4HF2→2TaF5+10NH4F+5H2O.

[0056] In these reactions, the tantalum and niobium oxides (Nb2O5 and Ta2O5) in the tantalum-niobium ore react with ammonium bifluoride to form the corresponding fluorides (NbF5 and TaF5) and ammonium fluoride (NH4F), while producing water (H2O). These fluorides can then be further processed and recovered through subsequent extraction and purification steps.

[0057] Step S2, the decomposition liquid is subjected to gradient elution using ion exchange resin as the stationary phase and hydrochloric acid as the mobile phase to obtain fluoroniobic acid, fluorotantalic acid and residual liquid respectively.

[0058] As mentioned above, ion exchange resin is a polymer material with ion exchange function, which is composed of a polymer matrix and fixed ions. This resin can absorb certain ions from a solution and release an equal amount of other ions. In this embodiment, the separation method using ion exchange resin can achieve efficient separation and purification of specific ions (tantalum and niobium) by controlling the flow rate, concentration and pH value of the eluent.

[0059] In this embodiment, an ion exchange resin is used.

[0060] The mobile phase is hydrochloric acid, which is an aqueous solution of hydrochloric acid in this embodiment. Using hydrochloric acid as the mobile phase for gradient elution of ion exchange resin can effectively separate and purify different components in the decomposition solution of tantalum-niobium ore, while taking into account the simplicity of operation, cost-effectiveness and environmental safety.

[0061] In the above-mentioned step S2, ion exchange resin and hydrochloric acid are used as mobile phases to separate different components in the decomposition solution, including fluoroniobic acid, fluorotantalic acid and residual liquid, by gradient elution technology.

[0062] The selective adsorption characteristics of ion exchange resins are used to separate different ions in the decomposition solution. By changing the concentration of hydrochloric acid, different components are gradually eluted. Thus, fluoroniobic acid and fluorotantalic acid, i.e., target products with higher purity, can be obtained. The residual liquid contains other impurities and unreacted substances.

[0063] High-purity fluoroniobic acid and fluorotantalic acid can be obtained by gradient elution, which reduces the large amount of acid used and the waste residue generated in the traditional method.

[0064] The flow rate and concentration of the eluent can be precisely controlled to achieve efficient separation. In addition, the separation efficiency can be further improved by setting multiple elution stages using a multi-stage elution method.

[0065] In some embodiments, the ammonium bifluoride solution is an ammonium bifluoride solution with a concentration of 400 g / L to 450 g / L. For example, the concentration may be 400 g / L, 410 g / L, 420 g / L, 430 g / L, 440 g / L, 450 g / L, and the like.

[0066] In some embodiments, the step S1, taking the target tantalum-niobium ore and adding it to an ammonium bifluoride solution for heating and decomposition, and obtaining a decomposed liquid after solid-liquid separation, comprises:

[0067] Step S11, preparing the ammonium bifluoride solution;

[0068] Step S12, under the condition of heating the ammonium bifluoride solution, mixing the target tantalum-niobium ore with the ammonium bifluoride solution, and subjecting the mixture to a stirring and dissolving process to obtain a dissolved mixture;

[0069] Step S13, performing solid-liquid separation on the dissolved mixture to obtain the decomposed liquid.

[0070] As mentioned above, in the extraction and separation method of tantalum-niobium ore, the mixing and dissolving process is carried out under the condition of heating the ammonium bifluoride solution in order to accelerate the chemical reaction rate between tantalum and niobium in the tantalum-niobium ore and the ammonium bifluoride, and improve the decomposition efficiency and extraction rate. By precisely controlling the heating temperature and time, the decomposition process can be optimized, the best decomposition effect can be obtained, and a high-quality decomposition solution can be provided for the subsequent ion exchange separation step.

[0071] In some embodiments, the heating temperature of the ammonium bifluoride is 70° C. to 80° C. For example, the heating temperature may be 70° C., 75° C., 80° C., and the like.

[0072] In some embodiments, the stirring and dissolving treatment lasts for 8 to 10 hours, for example, 8 hours, 9 hours, 10 hours, and the like.

[0073] In some embodiments, the pH of the dissolved mixture is 4-5; for example, the pH may be 4, 4.5, 5, and the like.

[0074] And / or, the target tantalum-niobium ore and the ammonium bifluoride solution have a liquid-to-solid ratio of 10:1 when mixed.

[0075] In some embodiments, the step S2, wherein the decomposition solution is subjected to gradient elution using an ion exchange resin as a stationary phase and hydrochloric acid as a mobile phase to obtain fluoroniobic acid, fluorotantalic acid and a residual liquid, respectively, comprises:

[0076] Step S21, after the ion exchange resin is loaded into the chromatography column, it is eluted with deionized water;

[0077] Step S22, adding the decomposition solution to a chromatography column for loading;

[0078] Step S23, using hydrochloric acid aqueous solutions of different concentrations to perform gradient elution on the chromatography column, and collecting fluoroniobic acid, fluorotantalic acid and residual liquid respectively.

[0079] In some embodiments, the step S23, using aqueous hydrochloric acid solutions of different concentrations to perform gradient elution on the chromatography column, comprises:

[0080] Step S231, using a hydrochloric acid aqueous solution of a first concentration, a hydrochloric acid aqueous solution of a second concentration, and a hydrochloric acid aqueous solution of a third concentration as mobile phases to elute the chromatography column.

[0081] Among them, the third concentration>the second concentration>the first concentration.

[0082] As mentioned above, in the ion exchange chromatography process, hydrochloric acid aqueous solution of different concentrations is used for gradient elution, wherein the third concentration is greater than the second concentration and greater than the first concentration, in order to improve the separation efficiency and selectivity. The lower concentration of hydrochloric acid first elutes the ions with lower affinity, while the gradually increasing concentration is used to elute the ions that are more tightly bound to the resin, which can avoid over-elution and reduce cross-contamination between components, thereby improving the purity of the collected fluoroniobic acid and fluorotantalate. In addition, gradient elution provides operational flexibility, allowing the elution conditions to be optimized by adjusting the order and proportion of use of hydrochloric acid of different concentrations to meet different separation requirements. This method also helps to improve the resolution between different components, so that fluoroniobic acid, fluorotantalate and residual liquid can be more clearly distinguished, while reducing the consumption of eluent, reducing costs, and achieving a more economical and practical separation process.

[0083] In some embodiments, the first concentration is 0.1 mol / L to 1 mol / L; for example, the first concentration may be 0.1 mol / L, 0.5 mol / L, 0.8 mol / L, 1.0 mol / L, and the like.

[0084] In some embodiments, the second concentration is 2 mol / L to 3 mol / L; for example, the second concentration may be 2 mol / L, 2.5 mol / L, 3 mol / L, and the like.

[0085] In some embodiments, the third concentration is 4 mol / L to 6 mol / L. For example, the third concentration may be 4 mol / L, 5 mol / L, 6 mol / L, and the like.

[0086] In some embodiments, the elution speeds using aqueous hydrochloric acid solutions of different concentrations are different;

[0087] In some embodiments, the elution rate of the first concentration of hydrochloric acid aqueous solution is 2 BV / h;

[0088] In some embodiments, the elution rate of the second concentration of hydrochloric acid aqueous solution is 5 BV / h;

[0089] In some embodiments, the elution rate of the third concentration of the aqueous hydrochloric acid solution is 7 BV / h.

[0090] In the above-mentioned extraction and separation method of tantalum-niobium ore, the elution speeds corresponding to different concentrations of hydrochloric acid aqueous solutions are different in order to optimize the elution conditions and improve the separation efficiency. By adjusting the flow rate of eluents of different concentrations, the elution of ions can be more effectively controlled, and the selectivity of separation and the purity of the target product can be improved.

[0091] In some embodiments, during the process of adding the decomposition solution to the chromatography column, the flow rate is controlled at 5 BV / h to 7 BV / h.

[0092] The present invention is further described below by means of specific examples, but it should be understood that these examples are only used for more detailed description and should not be construed as limiting the present invention in any form.

[0093] Example 1

[0094] In this embodiment, extraction and separation are carried out on the target tantalum-niobium ore.

[0095] Experimental methods:

[0096] (1) Pretreatment: The target tantalum-niobium ore is a tantalum-niobium ore that has been pre-treated by 100-mesh sieving, wherein the contents of the components in the target tantalum-niobium ore are Ta 6.4%, Nb 39.93%, Si 12.22%, Fe 28.7%, Mn 2.52% and O 10.23%, respectively.

[0097] (2) Decomposition: Prepare 1000L of ammonium bifluoride solution with a content of 400g / L, heat it to 70-80°C, weigh 100Kg of the target tantalum-niobium ore, stir and dissolve it for 9 hours, and then perform solid-liquid separation, that is, separation of the decomposition liquid and the decomposition slag. The obtained 900L decomposition liquid has a tantalum content of 7.05g / L and a niobium content of 44.10g / L; and 10Kg of decomposition slag (wet), with a tantalum decomposition rate of 99.2% and a niobium decomposition rate of 99.4%.

[0098] (3) Ion exchange separation:

[0099] 900 L of the decomposed liquid was treated with a cation exchange resin Dionex IonPac CS12A.

[0100] Use 200L of 0.8mol / L HCL eluent, control the elution rate at 2BV / h, and last for more than 60min. Detect the fluoroniobic acid content of the eluent. Collect 200L of fluoroniobic acid. The tantalum content in the fluoroniobic acid solution is 0.02g / L and the niobium content is 97.91g / L.

[0101] Use 400L of 2.2mol / L HCL eluent, control the elution rate at 5BV / h, and last for more than 90min. Detect the fluorotantalate content of the eluent and collect 400L of fluorotantalate. ， The tantalum content in the fluorotantalate solution is 30.84 g / L and the niobium content is 0.01 g / L;

[0102] Use 1000L of 4.5mol / L HCL eluent, control the elution rate at 7BV / h, and last for more than 120min. Detect the iron, manganese, and silicon contents in the residual liquid of the eluent, and collect the residual liquid with a volume of 1000L.

[0103] Example 2

[0104] In this embodiment, extraction and separation are carried out on the target tantalum-niobium ore.

[0105] Experimental methods:

[0106] The experimental method in this embodiment is basically the same as that in embodiment 1, except that:

[0107] (1) 900 L of decomposition liquid containing 7.06 g / L tantalum and 44.0 g / L niobium, and 12 kg (wet) of decomposition slag were obtained. The tantalum decomposition rate was 99.3%, and the niobium decomposition rate was 99.2%.

[0108] (2) 890 L of the decomposition liquid was treated with cation exchange resin (Japan) Diaion SK-1A.

[0109] Use 200L of 0.5mol / L HCL eluent, control the elution rate at 2BV / h, and last for 75min. Detect the fluoroniobic acid content of the eluent and collect 200L of fluoroniobic acid. ， The tantalum content in the fluoroniobate solution is 0.02g / L and the niobium content is 97.69g / L;

[0110] Use 400L of 2.5mol / L HCL eluent, control the elution rate at 5BV / h, and last for 80min. Detect the fluorotantalate content of the eluent and collect 500L of fluorotantalate. ， The tantalum content in the fluorotantalate solution is 31.40 g / L and the niobium content is 0.01 g / L;

[0111] Use 1000L of 5mol / L HCL eluent, control the elution rate at 7BV / h, and last for more than 120min. Detect the iron, manganese, and silicon contents in the residual liquid of the eluent, and collect 1000L of the residual liquid.

[0112] Example 3

[0113] In this embodiment, extraction and separation are carried out on the target tantalum-niobium ore.

[0114] Experimental methods:

[0115] The experimental method in this embodiment is basically the same as that in embodiment 1, except that:

[0116] (1) 900 L of decomposition liquid containing 7.07 g / L tantalum and 43.98 g / L niobium, and 12 kg (wet) of decomposition slag were obtained. The tantalum decomposition rate was 99.5%, and the niobium decomposition rate was 99.2%.

[0117] (2) 885 L of the decomposition liquid was treated with cation exchange resin (Japan) Diaion SK-1A.

[0118] Use 200L of 0.5mol / L HCL eluent, control the elution rate at 2BV / h, and last for 75min. Detect the fluoroniobic acid content of the eluent and collect 200L of fluoroniobic acid. ， The tantalum content in the fluoroniobate solution is 0.01 g / L and the niobium content is 97.81 g / L;

[0119] Use 400L of 2.5mol / L HCL eluent, control the elution rate at 5BV / h, and last for 80min. Detect the fluorotantalate content of the eluent and collect 400L of fluorotantalate. ， The tantalum content in the fluorotantalate solution is 30.60 g / L and the niobium content is 0.01 g / L;

[0120] Use 1100L of 5mol / L HCL eluent, control the elution rate at 7BV / h, and last for more than 120min. Detect the iron, manganese, and silicon contents in the residual liquid of the eluent, and collect 1100L of the residual liquid.

[0121] Example 4

[0122] In this embodiment, extraction and separation are carried out on the target tantalum-niobium ore.

[0123] Experimental methods:

[0124] The experimental method in this embodiment is basically the same as that in embodiment 1, except that:

[0125] (1) 900 L of decomposition liquid containing 7.02 g / L tantalum and 43.85 g / L niobium, and 12 kg (wet) of decomposition slag were obtained. The tantalum decomposition rate was 98.72%, and the niobium decomposition rate was 99.06%.

[0126] (2) 885 L of the decomposed liquid was treated with a cation exchange resin Dionex IonPac CS12A.

[0127] Use 200L of 0.5mol / L HCL eluent, control the elution rate at 2BV / h, and last for 80min. Detect the fluoroniobic acid content of the eluent and collect 200L of fluoroniobic acid. ， The tantalum content in the fluoroniobate solution is 0.02 g / L and the niobium content is 96.89 g / L;

[0128] Use 400L of 2.5mol / L HCL eluent, control the elution rate at 5BV / h, and last for 90min. Detect the fluorotantalate content of the eluent and collect 400L of fluorotantalate. ， The tantalum content in the fluorotantalate solution is 30.70 g / L and the niobium content is 0.01 g / L;

[0129] Use 1100L of 5mol / L HCL eluent, control the elution rate at 7BV / h, and last for more than 120min. Detect the iron, manganese, and silicon contents in the residual liquid of the eluent, and collect 1100L of the residual liquid.

[0130] Comparative Example 1

[0131] In this comparative example, extraction and separation were carried out on the target tantalum-niobium ore.

[0132] Experimental methods:

[0133] The preparation method is basically the same as that of Example 1, except that the concentration of ammonium bifluoride is 300 g / L, and the final 920 L decomposition liquid has a tantalum content of 5.78 g / L and a niobium content of 38.02 g / L; and the decomposition slag is 15 kg (wet), the tantalum decomposition rate is 83.5%, and the niobium decomposition rate is 86.4%.

[0134] Horizontal comparison experiment, results and analysis

[0135] Testing equipment: Inductively coupled plasma optical emission spectrometer (ICP-OES)

[0136] Test method: Using inductively coupled plasma optical emission spectrometer (ICP-OES), the target tantalum-niobium ore and decomposition solution in Examples 1 to 4, Comparative Example 1, and the tantalum and niobium in the final products fluoroniobic acid and fluorotantalate were detected and tracked.

[0137] Experimental results:

[0138] Table 1. Contents of raw materials, intermediates and final products obtained in Examples and Comparative Examples

[0139]

[0140] In the above table, "real" represents an example, such as "real 1" corresponds to Example 1. "Comparative" represents a comparative example, such as "Comparative 1" represents Comparative Example 1. The Ta content and Nb content of the decomposition liquid in the table are the contents of the corresponding elements in 900L of the decomposition liquid.

[0141] analyze:

[0142] (1) Referring to the data in Table 1, it can be seen that the Ta and Nb contents in the decomposition solution and their decomposition rates show the efficiency of the ammonium bifluoride decomposition process. The Ta and Nb decomposition rates of Examples 1 to 4 all exceeded 98.72%, indicating that the decomposition process of the embodiments using the method in the present application is very effective. The decomposition rates of Comparative Example 1 are relatively low, with Ta being 83.5% and Nb being 86.4%, which is due to the fact that the concentration range of the ammonium bifluoride solution in the method in the present application (400 g / L to 450 g / L) was not adopted, but a lower ammonium bifluoride concentration (300 g / L) was adopted.

[0143] (2) In the final product, the total yields of Ta and Nb in Examples 1 to 4 all exceeded 97%, indicating that the efficiency of the entire extraction and separation process was high. In the comparative example, since no cation exchange resin treatment was performed, only a small amount of ammonium bifluoride was added to decompose and obtain the decomposition liquid. If the yields were directly calculated, they could be: Ta 83.03% and Nb 87.60%, respectively, which were lower than the yields of the decomposition liquid in the examples and the total yields of the final products in the examples.

[0144] In summary, the tantalum-niobium ore extraction and separation method provided in the present application shows the characteristics of efficient decomposition, wherein the decomposition process using ammonium bifluoride solution (Examples 1 to 4) is very effective, and the decomposition rates of tantalum (Ta) and niobium (Nb) are generally higher than 97%. In addition, the total yield of these embodiments is relatively high, showing that the extraction and separation method is not only efficient, but also has relatively small losses throughout the process. Compared with the method using traditional high-concentration acid, the method using ammonium bifluoride solution significantly improves the extraction efficiency and resource recovery rate, while reducing environmental pollution and waste of resources, reflecting its environmental friendliness. The gradient elution technology of ion exchange resin further optimizes the process flow, improves product quality, and makes the technology more efficient and flexible. Compared with Comparative Example 1, the embodiment shows a higher decomposition rate and total yield, emphasizing the advantages of the present application in improving efficiency and reducing environmental impact. In summary, the data in Table 1 strongly support the effectiveness and superiority of the present application, that is, it provides a more environmentally friendly and efficient tantalum-niobium ore extraction and separation method.

[0145] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for extracting and separating tantalum-niobium ore, characterized in that: include: The target tantalum-niobium ore is added into an ammonium bifluoride solution for heating and decomposition, and a decomposition liquid is obtained after solid-liquid separation; The decomposition liquid is subjected to gradient elution using ion exchange resin as the stationary phase and hydrochloric acid as the mobile phase to obtain fluoroniobic acid, fluorotantalic acid and residual liquid respectively.

2. The method for extracting and separating tantalum-niobium ore according to claim 1, characterized in that: The ammonium bifluoride solution is an ammonium bifluoride solution with a concentration of 400 g / L to 450 g / L.

3. The method for extracting and separating tantalum-niobium ore according to claim 1, characterized in that: The target tantalum-niobium ore is added to an ammonium bifluoride solution for heating and decomposition, and a decomposed liquid is obtained after solid-liquid separation, comprising: preparing the ammonium bifluoride solution; Under the condition of heating the ammonium bifluoride solution, mixing the target tantalite niobium ore with the ammonium bifluoride solution, and subjecting the mixture to a stirring and dissolving process to obtain a dissolved mixture; The dissolved mixture is subjected to solid-liquid separation to obtain the decomposed liquid.

4. The method for extracting and separating tantalum-niobium ore according to claim 3, characterized in that: The heating temperature of the ammonium bifluoride is 70°C to 80°C.

5. The method for extracting and separating tantalum-niobium ore according to claim 3, characterized in that: The stirring and dissolving treatment takes 8 to 10 hours.

6. The method for extracting and separating tantalum-niobium ore according to claim 3, characterized in that: The pH of the dissolved mixture is 4 to 5; and / or, The target tantalum-niobium ore has a liquid-to-solid ratio of 10:1 when mixed with the ammonium bifluoride solution.

7. The method for extracting and separating tantalum-niobium ore according to claim 1, characterized in that: The decomposition liquid is subjected to gradient elution using an ion exchange resin as a stationary phase and hydrochloric acid as a mobile phase to obtain fluoroniobic acid, fluorotantalic acid and a residual liquid, respectively, including: After the ion exchange resin is loaded into the chromatography column, it is eluted with deionized water; Adding the decomposition solution to a chromatography column for loading; The chromatography column is gradient eluted using aqueous hydrochloric acid solutions of different concentrations, and fluoroniobic acid, fluorotantalic acid and residual liquid are collected respectively.

8. The method for extracting and separating tantalum-niobium ore according to claim 7, characterized in that: The step of using aqueous hydrochloric acid solutions of different concentrations to perform gradient elution on the chromatography column comprises: Sequentially using a hydrochloric acid aqueous solution of a first concentration, a hydrochloric acid aqueous solution of a second concentration, and a hydrochloric acid aqueous solution of a third concentration as mobile phases to elute the chromatography column; Among them, the third concentration>the second concentration>the first concentration; Preferably, the first concentration is 0.1 mol / L to 1 mol / L; Preferably, the second concentration is 2 mol / L to 3 mol / L; Preferably, the third concentration is 4 mol / L to 6 mol / L.

9. The method for extracting and separating tantalum-niobium ore according to claim 8, characterized in that: The elution speeds are different when using aqueous hydrochloric acid solutions of different concentrations; Preferably, the elution rate of the hydrochloric acid aqueous solution of the first concentration is 2 BV / h; Preferably, the elution rate of the second concentration of the hydrochloric acid aqueous solution is 5 BV / h; Preferably, the elution rate of the hydrochloric acid aqueous solution of the third concentration is 7 BV / h.

10. The method for extracting and separating tantalum-niobium ore according to claim 7, characterized in that: During the loading process of adding the decomposition solution into the chromatography column, the flow rate is controlled at 5 BV / h to 7 BV / h.

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