Production methods and applications of niobium hydroxide in tantalum-niobium hydrometallurgy

Abstract

This invention provides a method for producing niobium hydroxide in tantalum-niobium hydrometallurgy and its application, relating to the field of tantalum-niobium hydrometallurgical technology. The method involves grinding tantalum-niobium ore to obtain tantalum-niobium particles; adding hydrofluoric acid and sulfuric acid to the tantalum-niobium particles to carry out a decomposition reaction, obtaining a decomposition liquid containing tantalum-niobium; adjusting the acidity of the decomposition liquid containing tantalum-niobium, and then extracting it with MIBK to obtain an organic phase supported on tantalum-niobium; acid washing the organic phase containing tantalum-niobium, obtaining a tantalum-niobium supported phase; extracting the tantalum-niobium supported phase with anti-niobium solution to obtain a fluoroniobic acid solution; adding urea to the fluoroniobic acid solution for a neutralization reaction, and filtering to obtain crude niobium hydroxide; rinsing the crude niobium hydroxide, and then drying it to obtain the finished niobium hydroxide product. By using urea as a neutralizing agent, liquid ammonia is no longer used, significantly reducing production risks and lowering the cost of safe production.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of tantalum-niobium hydrometallurgy, and particularly relates to a production method of niobium hydroxide in tantalum-niobium hydrometallurgy and application thereof. BACKGROUND

[0002] In the case of tantalum-niobium raw materials associated with each other, most of the areas in China adopt tantalum-niobium hydrometallurgy, HF and H2SO4 are used for leaching, and then MIBK or 2-octanol is used for tantalum-niobium extraction and tantalum-niobium separation, niobium is washed with sulfuric acid, after acid washing, niobium is back-extracted into a sulfuric acid solution to generate a fluoroniobate solution, and then the fluoroniobate solution is neutralized by using vaporized ammonia to generate niobium hydroxide; in this process, liquid ammonia is needed for neutralization, but the storage and use of liquid ammonia have high safety requirements, resulting in an increase in the cost of safe production.

[0003] In the prior art, a kind of superfine niobium oxide neutralization precipitation process is disclosed in Chinese patent application No. 202410628892.3, the specific process steps of the invention include: acidity adjustment: adjust the pH of fluoroniobate solution to 1.0-1.5 to obtain acidified niobium solution; neutralization reaction: under stirring, add a neutralizing agent to the acidified niobium solution to adjust the pH of the acidified niobium solution to 9.0-9.5, then transfer to a filter press, after feeding is completed, start washing with washing water until the mass concentration of F element in the washing liquid is less than 500 mg / L; unload the filter cake in the filter press and dry to obtain a precursor for preparing superfine niobium oxide; the neutralizing agent is selected from the combination of ammonium bicarbonate solution and sodium hydroxide solution; in the above prior art, ammonium bicarbonate solution and sodium hydroxide solution are used as liquid-phase neutralization precipitants to obtain superfine niobium oxide, which does not use liquid ammonia to reduce the cost of safe production, but the introduction of other impurities affects the quality of the prepared product. SUMMARY

[0004] Therefore, the application provides a production method of niobium hydroxide in tantalum-niobium hydrometallurgy, which can reduce the cost and does not introduce other impurities.

[0005] It is also necessary to provide an application of the production method of niobium hydroxide in tantalum-niobium hydrometallurgy.

[0006] The technical solution adopted by the application to solve the technical problems is as follows:

[0007] A production method of niobium hydroxide in tantalum-niobium hydrometallurgy, comprising the following steps:

[0008] Grinding: grinding tantalum-niobium ore to obtain tantalum-niobium particles;

[0009] Decomposition: adding hydrofluoric acid and sulfuric acid to the tantalum-niobium particles for decomposition reaction to obtain a tantalum-niobium-containing decomposition solution;

[0010] Extraction: the tantalum and niobium-containing decomposition solution is adjusted in acidity, and after adjustment in acidity, extraction is performed with MIBK to obtain an organic phase loaded with tantalum and niobium;

[0011] Pickling: the organic phase loaded with tantalum and niobium is subjected to pickling, and after pickling, a tantalum and niobium loaded phase is obtained;

[0012] Reverse niobium: the tantalum and niobium loaded phase is subjected to extraction with a reverse niobium solution to obtain a fluoro niobate solution;

[0013] Neutralization: urea is added to the fluoro niobate solution to perform a neutralization reaction, and a crude niobium hydroxide product is obtained after filtration;

[0014] Drying: the crude niobium hydroxide product is subjected to leaching, and after leaching, drying is performed to obtain a niobium hydroxide product.

[0015] Preferably, the step of adding urea to the fluoro niobate solution to perform a neutralization reaction comprises the following steps:

[0016] S1: urea is decomposed at a predetermined temperature to obtain a decomposition gas;

[0017] S2: the decomposition gas is added to the fluoro niobate solution to perform a neutralization reaction, and after the reaction, a niobium hydroxide product is obtained after filtration.

[0018] Preferably, in the S1 step, the predetermined temperature is 120°C to 180°C.

[0019] Preferably, in the tantalum and niobium ore, the ratio of tantalum and niobium to hydrofluoric acid and sulfuric acid is 1 kg of tantalum and niobium: 1.5 L to 1.8 L of HF: 0.2 L to 0.3 L of H2SO4, and the mass ratio of niobium in the fluoro niobate to the urea is greater than or equal to 1:1.5.

[0020] Preferably, in the ore grinding step, the particle size of the tantalum and niobium particles is -200 mesh to -300 mesh.

[0021] Preferably, in the decomposition step, the decomposition reaction requires heat preservation, the heat preservation temperature is 80°C to 95°C, and the decomposition time is more than 6 hours.

[0022] Preferably, in the extraction step, after the tantalum and niobium-containing decomposition solution is adjusted in acidity, the sulfuric acid acidity is 3.75 to 4.25 mol / L, and the hydrofluoric acid acidity is 5.5 mol / L to 6.5 mol / L, and after adjustment in acidity, extraction is performed with MIBK, the tantalum and niobium content ratio in the decomposition solution is (1-5):(1-5), the extraction level is more than 10 levels, and an organic phase loaded with tantalum and niobium is obtained.

[0023] Preferably, in the reverse niobium step, the reverse niobium solution has an acidity of 0.7-0.8 mol / L, and the volume ratio of the tantalum and niobium loaded phase to the reverse niobium solution is 3:(3-1), and the extraction level is more than 6 levels.

[0024] Preferably, in the drying step, the crude niobium hydroxide is leached to a pH of 6-6.5

[0025] The application of the method for producing niobium hydroxide in tantalum-niobium hydrometallurgy as described above also includes a reduction step: roasting the niobium hydroxide product to obtain niobium oxide.

[0026] Compared with the prior art, the method has the following beneficial effects:

[0027] The method for producing niobium hydroxide in tantalum-niobium hydrometallurgy includes the following steps: grinding tantalum-niobium ore to obtain tantalum-niobium particles; adding hydrofluoric acid and sulfuric acid to the tantalum-niobium particles to perform a decomposition reaction to obtain a tantalum-niobium-containing decomposition solution; adjusting the acidity of the tantalum-niobium-containing decomposition solution, and then performing extraction with MIBK to obtain a tantalum-niobium-loaded organic phase; performing pickling on the tantalum-niobium-loaded organic phase to obtain a tantalum-niobium-loaded phase; performing extraction on the tantalum-niobium-loaded phase with anti-niobium solution to obtain a fluoro niobate solution; adding urea to the fluoro niobate solution to perform a neutralization reaction, and then filtering to obtain crude niobium hydroxide; performing leaching on the crude niobium hydroxide, and then performing drying to obtain a niobium hydroxide product; by using urea as a neutralizing agent for neutralization, on the one hand, liquid ammonia is no longer used, which greatly reduces the production risk and reduces the cost of safe production, thereby reducing the cost of safe production; on the other hand, using urea as a neutralizing agent for neutralization reaction does not introduce foreign impurity elements and does not affect the quality of the niobium hydroxide; on the other hand, using urea as a neutralizing agent makes the prepared niobium hydroxide have a finer particle size and better quality. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 Particle size detection distribution diagram of the niobium hydroxide prepared for Example 1.

[0029] Figure 2 Particle size detection distribution diagram of the niobium hydroxide prepared for Comparative Example 1. DETAILED DESCRIPTION

[0030] The technical solutions and technical effects of the embodiments of the present application are further described in detail in combination with the drawings of the present application.

[0031] A method for producing niobium hydroxide in tantalum-niobium hydrometallurgy includes the following steps:

[0032] Grinding: grinding tantalum-niobium ore to obtain tantalum-niobium particles; so that the tantalum-niobium decomposition leaching effect is good;

[0033] Specifically, the tantalum-niobium content in the tantalum-niobium ore is about 40%-50%.

[0034] Decomposition: Hydrofluoric acid and sulfuric acid are added to tantalum and niobium particles to carry out a decomposition reaction, so that the tantalum and niobium raw materials in the tantalum and niobium particles react with hydrofluoric acid to generate fluorotantalic acid and fluoroniobic acid, so as to separate them from other impurities in the ore and obtain a decomposition liquid containing tantalum and niobium.

[0035] Extraction: The decomposition solution containing tantalum and niobium is acidified and then extracted with MIBK to extract fluorotantalic acid and fluoroniobic acid in the decomposition solution into the MIBK extractant, so as to extract tantalum and niobium from the decomposition solution containing fluoride salts and sulfates, and obtain an organic phase supported on tantalum and niobium.

[0036] Acid washing: The organic phase containing tantalum and niobium is acid washed to obtain the tantalum and niobium supported phase;

[0037] Specifically, sulfuric acid is used to reduce the content of metal impurities in the tantalum-niobium supported organic phase;

[0038] Anti-niobium: The tantalum-niobium supported phase is extracted with anti-niobium solution to separate fluorotantalic acid and fluoroniobic acid in the supported phase, and a fluoroniobic acid solution is obtained;

[0039] Neutralization: Urea was added to the fluoroniobic acid solution to carry out a neutralization reaction, and the crude niobium hydroxide was obtained by filtration.

[0040] Drying: The crude niobium hydroxide is rinsed and then dried to obtain the niobium hydroxide product.

[0041] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0042] This invention discloses a method for producing niobium hydroxide in tantalum-niobium hydrometallurgy. The method involves grinding tantalum-niobium ore to obtain tantalum-niobium particles; adding hydrofluoric acid and sulfuric acid to the tantalum-niobium particles to perform a decomposition reaction, obtaining a decomposition solution containing tantalum and niobium; adjusting the acid content of the decomposition solution, followed by extraction with MIBK to obtain an organic phase supported on tantalum and niobium; acid washing the organic phase to obtain a tantalum-niobium supported phase; extracting the tantalum-niobium supported phase with anti-niobium solution to obtain a fluoroniobic acid solution; adding urea to the fluoroniobic acid solution for neutralization, filtering to obtain crude niobium hydroxide; and then... Crude niobium oxide is leached and then dried to obtain niobium hydroxide. Neutralization is achieved by using urea as a neutralizing agent. This eliminates the need for liquid ammonia, significantly reducing production risks and safety costs. Furthermore, using urea as a neutralizing agent avoids introducing foreign impurities without affecting the formation of niobium hydroxide, thus preserving its quality. Additionally, using urea results in finer particle size and higher quality niobium hydroxide.

[0043] Furthermore, the neutralization reaction of adding urea to the fluoroniobic acid solution includes the following steps:

[0044] S1: urea is decomposed at a predetermined temperature to obtain a decomposition gas;

[0045] S2: the decomposition gas is added to the fluoroniobate solution to perform a neutralization reaction, and after the reaction, the pH is 6-9, filtration is performed to make the reaction complete and ensure the yield, and the niobium hydroxide product is obtained after filtration.

[0046] The urea must be decomposed first to obtain a decomposition gas, and the decomposition gas is used to perform a neutralization reaction with fluoroniobate or fluoroniobate to generate niobium hydroxide, so as to reduce the impurity content. If urea is directly added to the fluoroniobate solution, white precipitates are generated after thermal decomposition of urea, resulting in high impurity content in the niobium hydroxide.

[0047] Further, in the S1 step, the predetermined temperature is 120-180°C.

[0048] Specifically, the fluoroniobate solution is transferred to a neutralization tank, and urea is added to a urea decomposition device. The urea is decomposed into ammonia gas and carbon dioxide at 120-180°C. The ammonia gas and carbon dioxide enter the neutralization tank through a polyethylene pipeline. The ammonia gas reacts with the fluoroniobate, and after the reaction, the niobium hydroxide is obtained after filtration. On the one hand, the decomposition gas is gradually added to the fluoroniobate solution, so that the neutralization reaction is sufficient. On the other hand, the decomposition of ammonia gas and carbon dioxide itself carries the temperature after preheating. The ammonia gas and carbon dioxide do not cause temperature fluctuations during the neutralization reaction process, so that the neutralization reaction temperature is stable, and the prepared niobium hydroxide has finer particle size and better quality.

[0049] Further, the ratio of tantalum niobium to hydrofluoric acid and sulfuric acid in the tantalum niobium ore is 1 kg of tantalum niobium: 1.5L-1.8L of HF: 0.2L-0.3L of H2SO4, and the mass ratio of niobium in the fluoroniobate to the urea is greater than or equal to 1:1.5.

[0050] Further, in the ore grinding step, the particle size of the tantalum niobium particles is -200 mesh to -300 mesh. The particle size is negative because the standard size of the screen is 200 mesh and 300 mesh. The screen indicates that there are 200 and 300 screen holes per inch of screen, respectively. The negative sign before the mesh number indicates that the mesh hole can pass through the mesh number, i.e., the particle size is smaller than the mesh hole size.

[0051] Further, in the decomposition step, the decomposition reaction requires insulation, the insulation temperature is 80-95°C, which prevents the volatilization of hydrofluoric acid and makes the tantalum niobium particles react vigorously with hydrofluoric acid. The decomposition time is more than 6h.

[0052] Further, in the extraction step, the tantalum and niobium-containing decomposition solution is adjusted in acidity, the sulfuric acid has an acidity of 3.75-4.25 mol / L, and the hydrofluoric acid has an acidity of 5.5-6.5 mol / L, if the acidity of the tantalum and niobium-containing decomposition solution is too low, the industrial sulfuric acid is used to adjust the acidity, if the acidity is too high, the pure water is used to adjust the acidity, and then the tantalum and niobium-containing decomposition solution is extracted with MIBK, the content ratio of tantalum and niobium in the decomposition solution is (1-5):(1-5), the extraction level is more than 10, and the tantalum and niobium-loaded organic phase is obtained.

[0053] Further, in the anti-niobium step, the anti-niobium solution has an acidity of 0.7-0.8 mol / L, and the volume ratio of the tantalum and niobium-loaded phase to the anti-niobium solution is 3:(3-1), and the extraction level is more than 6.

[0054] Specifically, the anti-niobium solution is a dilute sulfuric acid solution with an acidity of 0.7-0.8 mol / L.

[0055] Further, in the drying step, the niobium hydroxide crude product is leached to have a pH of 6-6.5, and then is dried in an oven at 90-120 DEG C to obtain the niobium hydroxide product.

[0056] The application of the method for producing niobium hydroxide in the tantalum and niobium hydrometallurgy as described above also comprises a reduction step: the niobium hydroxide product is calcined to obtain niobium oxide.

[0057] In order to facilitate understanding, the application is further illustrated by the following examples: Example 1

[0058] Grinding: 6000 kg of tantalum and niobium ore is added to a Raymond mill for grinding, and the particle size of the ground tantalum and niobium ore is between-200 and-300 meshes, and the tantalum and niobium particles are obtained.

[0059] Decomposition: 6000 kg of the obtained tantalum and niobium particles are added to a decomposition reactor, and then 8200 L of hydrofluoric acid and 2500 L of sulfuric acid are delivered into the decomposition reactor by a compression pump to decompose, the temperature is kept at 80-95 DEG C during the decomposition, and the decomposition is carried out for more than 6 hours, and the tantalum and niobium-containing decomposition solution is obtained.

[0060] Extraction: the tantalum and niobium-containing decomposition solution is adjusted in acidity, the sulfuric acid has an acidity of 3.75-4.25 mol / L, and the hydrofluoric acid has an acidity of 5.5-6.5 mol / L, and then the tantalum and niobium-containing decomposition solution is extracted with MIBK, the content ratio of tantalum and niobium in the decomposition solution is (1-5):(1-5), the extraction level is more than 10, and the tantalum and niobium-loaded organic phase is obtained.

[0061] Acid washing: the obtained tantalum and niobium loaded organic phase is subjected to acid washing with 4-4.5 mol / L dilute sulfuric acid solution, the acid washing solution has a concentration of 4-4.5 mol / L, the volume ratio of the tantalum and niobium loaded organic phase to the acid washing solution is (3-4):1, the extraction stage is 6 or more, and the tantalum and niobium loaded phase is obtained after acid washing.

[0062] Reverse niobium: the obtained tantalum and niobium loaded phase is subjected to extraction with a reverse niobium solution, the reverse niobium solution has a concentration of 0.7-0.8 mol / L dilute sulfuric acid solution, the reverse niobium solution has a concentration of 0.7-0.8 mol / L, the volume ratio of the tantalum and niobium loaded phase to the reverse niobium solution is 3:(3-1), the extraction stage is 6 or more, and the fluoro niobate solution is obtained after reverse niobium.

[0063] Neutralization: the obtained fluoro niobate solution is transferred to a neutralization tank, 1000 kg of urea is added to a urea decomposition device, the decomposition temperature is 120℃, a polyethylene pipeline is connected from the urea decomposition exhaust port to the neutralization tank, the ammonia gas generated after urea decomposition is subjected to neutralization reaction with the fluoro niobate, the pH is 8-9, and the niobium hydroxide is obtained after filtration.

[0064] Drying: the obtained niobium hydroxide is washed with pure water to pH 6, and dried in a 90℃ oven to obtain the niobium hydroxide product. Example 2:

[0065] In the neutralization step, the decomposition temperature is 140℃; in the drying step, the drying temperature is 100℃, and the other steps are the same as in Example 1. Example 3:

[0066] In the neutralization step, the decomposition temperature is 160℃; in the drying step, the drying temperature is 110℃.

[0067] Reduction step: the niobium hydroxide is calcined at a high temperature of 800℃-900℃ for 3-4 hours to obtain the niobium pentoxide.

[0068] The other steps are the same as in Example 1.

[0069] Comparative Example 1:

[0070] Neutralization: the obtained fluoro niobate solution is transferred to a neutralization tank, liquid ammonia is transported to a vaporizer device through a pipeline, the vaporizer device converts the liquid ammonia into gaseous ammonia, the gaseous ammonia is introduced into the neutralization tank containing the fluoro niobate solution, and the neutralization reaction is carried out, the pH is 8-9, and the niobium hydroxide is obtained after filtration.

[0071] The other steps are the same as in Example 1.

[0072] The niobium hydroxide obtained in Examples 1-3 and Comparative Example 1 is subjected to direct current arc atomic emission spectrometry by a direct current arc spectrometer, and the detection data are shown in Table 1.

[0073] Table 1

[0074]

[0075] As shown in Table 1, the preparation of niobium hydroxide by urea decomposition in this invention is feasible and can reach the level of preparation using liquid ammonia, without the influence of external impurities.

[0076] The niobium hydroxide obtained in Example 1 and Comparative Example 1 was subjected to particle size analysis, and the results are as follows: Figure 1 , Figure 2 As shown, by Figure 1 , Figure 2 It can be seen that the niobium hydroxide prepared by urea decomposition in this invention has a finer particle size distribution.

[0077] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the above-described embodiments and making equivalent changes in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A process for the production of niobium hydroxide in the hydrometallurgy of tantalum niobium, characterized by, The method comprises the following steps: Grinding: grinding the tantalum-niobium ore to obtain tantalum-niobium particles; Decomposition: adding hydrofluoric acid and sulfuric acid to the tantalum-niobium particles to perform a decomposition reaction to obtain a tantalum-niobium-containing decomposition solution; Extraction: adjusting the acid of the tantalum-niobium-containing decomposition solution, and then performing extraction with MIBK to obtain an organic phase containing tantalum-niobium-loaded; Acid washing: performing acid washing on the organic phase containing tantalum-niobium-loaded to obtain a tantalum-niobium-loaded phase; Anti-niobium: performing extraction on the tantalum-niobium-loaded phase with an anti-niobium solution to obtain a fluoro niobate solution; Neutralization: adding urea to the fluoro niobate solution to perform a neutralization reaction, and filtering to obtain a crude niobium hydroxide product; The step of adding urea to the fluoro niobate solution to perform a neutralization reaction comprises the following steps: S1: decomposing urea at 120-180°C to obtain a thermal decomposition gas; S2: adding the thermal decomposition gas to the fluoro niobate solution to perform a neutralization reaction, and filtering to obtain a niobium hydroxide product after the reaction; the decomposition of ammonia and carbon dioxide is preheated to carry the temperature, and the ammonia and carbon dioxide will not cause the temperature fluctuation in the neutralization reaction process after being introduced, so that the neutralization reaction temperature is stable, and the particle size of the prepared niobium hydroxide is finer; Drying: performing leaching on the crude niobium hydroxide product, and then performing drying to obtain a niobium hydroxide product.

2. The process for producing niobium hydroxide in tantalum-niobium hydrometallurgy according to claim 1, characterized by, The mass ratio of tantalum-niobium to hydrofluoric acid and sulfuric acid in the tantalum-niobium ore is 1 kg of tantalum-niobium: 1.5-1.8 L of HF: 0.2-0.3 L of H2SO4, and the mass ratio of niobium in the fluoro niobate to the urea is greater than or equal to 1:1.

5.

3. The process for producing niobium hydroxide in tantalum-niobium hydrometallurgy according to claim 1, characterized by, In the grinding step, the particle size of the tantalum-niobium particles is -200 mesh to -300 mesh.

4. The process for producing niobium hydroxide in tantalum-niobium hydrometallurgy according to claim 1, characterized by, In the decomposition step, the decomposition reaction needs to be kept warm, the temperature is 80-95°C, and the decomposition time is more than 6 hours.

5. The process for producing niobium hydroxide in tantalum-niobium hydrometallurgy according to claim 1, characterized by, In the extraction step, after the tantalum-niobium-containing decomposition solution is adjusted, the sulfuric acid has a concentration of 3.75-4.25 mol / L, and the hydrofluoric acid has a concentration of 5.5-6.5 mol / L; after the adjustment, extraction is performed with MIBK, the tantalum-niobium content in the decomposition solution is (1-5):(1-5), the extraction level is more than 10, and the organic phase containing tantalum-niobium-loaded is obtained.

6. The process for producing niobium hydroxide in tantalum-niobium hydrometallurgy according to claim 1, characterized by, In the anti-niobium step, the anti-niobium solution has a concentration of 0.7-0.8 mol / L, and the volume ratio of the tantalum-niobium-loaded phase to the anti-niobium solution is 3:(3-1), and the extraction level is more than 6.

7. The process for producing niobium hydroxide in tantalum-niobium hydrometallurgy according to claim 1, characterized by, In the drying step, the crude niobium hydroxide product is leached to a pH of 6-6.5.

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