Method for preparing low-antimony niobium oxide by removing antimony from fluorine niobic acid solution

Abstract

The invention relates to the technical field of purification and impurity removal, and discloses a method for preparing low-antimony niobium oxide by removing antimony from a fluoroniobic acid solution, which comprises the following steps: adding peroxide into the fluoroniobic acid solution for complexing, then adding ammonia to adjust the precipitation pH value of the solution to obtain niobium salt precipitation, carrying out solid-liquid separation, and roasting to obtain the low-antimony niobium oxide. According to the method, the deep removal of antimony in the fluorine niobic acid solution can be realized, and the obtained niobium-containing peroxide complex can meet the requirements of preparing a 4N-grade high-purity niobium oxide product; the method does not need to consume expensive special reagents, only needs to consume part of peroxy ions, is low in cost and small in pollution, and is beneficial to product quality; the whole process is simple to operate, does not need other matched impurity removal equipment, is low in investment and short in flow, and is easy to realize continuous production.

Description

Technical Field

[0001] The present invention relates to the technical field of purification and impurity removal, and particularly to a method for preparing low-antimony niobium oxide by removing antimony from a hydrofluoric niobate solution. Background Art

[0002] With the rapid development of high-tech fields such as electronics, microelectronics, and new energy, high-purity niobium oxide (Nb2O5), as a key functional material, has increasingly stringent requirements for its purity. If the antimony content in high-purity niobium oxide exceeds the standard (>5 ppm), it will significantly affect its application performance in high-end fields. For example, in the electronics field: antimony can cause deterioration of the dielectric properties of lithium niobate single crystals, affecting the stability of optoelectronic devices; in the field of superconducting materials: trace amounts of antimony impurities may damage the lattice structure of the material, reducing the superconducting critical temperature; in the new energy field: the presence of antimony will exacerbate the side reactions of the cathode material of lithium-ion batteries, shortening the cycle life. However, antimony (Sb), as an impurity element with similar chemical properties to niobium (Nb), has become the core technical bottleneck restricting the improvement of the purity of niobium oxide due to its extremely low separation coefficient from niobium in the extraction system (Nb < Sb < Ta). Therefore, achieving efficient removal of antimony from the hydrofluoric niobate solution is the core challenge in preparing low-antimony niobium oxide.

[0003] Chinese invention patent publication number CN102358918A discloses a method for removing antimony from ultra-high-purity tantalum pentoxide and niobium pentoxide. This method removes antimony from the tantalum and niobium solutions by using D296 resin to adsorb tantalum and D290 resin to adsorb niobium, respectively, in a secondary octanol system. This method requires a long cycle and consumes a large amount of water. The D290 resin adsorbs large amounts of tantalum and niobium, resulting in low antimony removal efficiency. Chinese invention patent publication number CN103408070A discloses a process for removing antimony from niobium-tantalite to produce high-purity niobium oxide. The method first uses 36% hydrochloric acid to leach the niobium-tantalite to remove most of the antimony. The tantalum and niobium are then decomposed using sulfuric acid and hydrofluoric acid. A hydrazine solution is added to reduce the high-valent antimony in the leachate. Finally, high-purity niobium oxide is obtained through secondary octanol extraction, niobium decomposition, neutralization, and calcination. However, this method requires hydrochloric acid, which can easily introduce chloride ion contamination. Furthermore, hydrazine is a colorless, highly hygroscopic, flammable liquid that can explode upon long-term exposure and is also carcinogenic. Chinese Invention Patent Publication No. CN104477993A discloses a method for preparing high-purity niobium oxide using a high-antimony niobium solution and the resulting product. The method involves adding a saturated ammonium sulfate solution to a high-antimony niobium solution, controlling the niobium concentration to ≥70 g / L and the acidity to ≥3N. The acid-adjusted niobium solution is then extracted and stripped with octanol to produce a pure niobium solution. This solution is then neutralized and precipitated, and calcined at 900-1000°C to produce high-purity niobium oxide. This method introduces a saturated ammonium sulfate solution to alter the chemical valence of antimony, and then performs a gradient extraction process. This method extracts a large amount of niobium solution to purify the solution, leaving antimony in the raffinate. This method, which also extracts the target metal, results in relatively low impurity removal efficiency. Chinese invention patent publication number CN108862384B discloses a method for preparing low-antimony niobium oxide and a method for preparing low-antimony tantalum oxide. The method involves first reducing antimony in a solution to a low-valent state (+3) using a carboxylic acid reducing agent, then adding triethanolamine or sulfide ethanolamine as a complexing agent to form a stable antimony complex. The product is then neutralized with alkali, washed, dried, and calcined to achieve efficient separation of the niobium or tantalum product from antimony. Similarly, Chinese invention patent publication number CN109097572A discloses a method for removing antimony impurities from tantalum and niobium hydrometallurgy. TaSb and NbSb are separated by adding a water-soluble antimony complexing agent to an aqueous solution of fluoroniobic acid / fluorotantalic acid, followed by neutralization and precipitation with ammonia, washing, and filtration. The Chinese invention patent with publication number CN108862384B, "A method for preparing low-antimony niobium oxide and a method for preparing low-antimony tantalum oxide", and the Chinese invention patent with publication number CN109097572A, "A method for removing antimony impurities in the hydrometallurgy of tantalum and niobium", introduce triethanolamine or ethanolamine sulfide, 2,3-dimercaptopropanesulfonic acid, and 2,3-dimercaptosuccinic acid (DMSA), which are organic compounds. The reagent cost is relatively high and it is easy to introduce organic matter and organic sulfur and other pollution during neutralization and precipitation.Chinese invention patent publication number CN118389834A discloses a "Method for Deep Purification of Tantalum-Niobium Metallurgical Solutions." This method involves oxidation, acid adjustment, and foam removal to capture difficult-to-separate impurities at moderate acidity. Furthermore, through acid adjustment and niobium extraction, the target metal is separated at high acidity, ultimately yielding a clean, reversed-niobium solution. Chinese invention patent publication number CN119351791A discloses a "Method for Deep Removal of Antimony and Tantalum from Niobium-Containing Solutions." A niobium solution containing antimony, tantalum, and fluorine is first oxidized and complexed with an inorganic peroxide, followed by acid adjustment and extraction to produce a purified niobium-containing solution. However, this method requires multiple stages of countercurrent extraction to remove antimony from the solution, resulting in complex steps and high equipment investment. Furthermore, the organic reagents are somewhat water-soluble, easily exceeding the TOC standard and causing secondary contamination of the product. Generally speaking, the existing technical route has cumbersome processes and complex operation procedures. It mainly obtains pure niobium liquid through repeated extraction / adsorption of the main element niobium. However, the concentration of niobium liquid in the metallurgical process can generally reach 60-90g / L. The re-extraction process will cause a large amount of organic phase / adsorption resin to be consumed, energy consumption will increase, and the impurity removal efficiency is low. Some patented technologies also require the consumption of additional expensive reducing agents, chelating agents and foam stabilizers, which are difficult to recycle and reuse. This not only greatly increases the cost of impurity removal, but also easily causes pollution and seriously affects product quality.

[0004] In addition, with the depletion of high-grade niobium-tantalum ore resources, the proportion of low-grade, high-impurity raw materials (such as antimony-containing niobium-tantalum iron ore) has increased. Traditional processes are based on the design of high-quality niobium concentrates and are difficult to adapt to complex raw material systems, resulting in large fluctuations in the antimony content in the decomposition liquid, which is difficult to stably control with existing methods; the synergistic effect of multiple impurities (such as the coexistence of Fe and Sb) further reduces the separation efficiency. In the existing technology, the cost of wastewater treatment (such as fluorine- and antimony-containing wastewater) is high and the resource utilization rate is low. For example, the antimony-containing sludge produced by the traditional neutralization method needs to be disposed of as hazardous waste, and although membrane separation technology can achieve near-zero wastewater discharge, the equipment investment and operating costs are significantly increased. The existing technology generally has problems such as complex process flow, low separation efficiency, high cost, and high environmental pressure, which makes it difficult to meet the needs of large-scale production of high-purity niobium oxide. Therefore, there is an urgent need to develop an efficient, economical, and environmentally friendly method for removing antimony from fluoroniobic acid solution to prepare low-antimony niobium oxide, break through the technical bottleneck of separation of antimony and niobium, and provide reliable raw material guarantees for the field of high-end materials. Summary of the Invention

[0005] The present invention aims to overcome the difficulties and high costs associated with existing technologies in separating antimony and niobium. It provides a method for removing antimony from a fluoniobic acid solution to produce low-antimony niobium oxide. The fluoniobic acid solution is subjected to peroxide complexation, ammonia neutralization, and precipitation to obtain a niobium salt precipitate with a low antimony content. Conventional filtration and calcination are then performed to produce low-antimony niobium oxide, a high-purity niobium oxide product. This method is simple to operate, achieves high niobium and antimony separation efficiency, shortens the process, reduces costs, and allows for easily controlled conditions.

[0006] To achieve the above object, the present invention is implemented according to the following technical solutions:

[0007] A method for preparing low-antimony niobium oxide by removing antimony from a fluoroniobic acid solution comprises the following steps: adding peroxide to the fluoroniobic acid solution for complexation, then adding ammonia to adjust the precipitation pH of the solution to obtain a niobium salt precipitate, and then calcining the niobium oxide after solid-liquid separation.

[0008] Specifically, peroxide is added to a fluoroniobic acid solution so that niobium in the fluoroniobic acid solution exists in the form of a peroxide complex; ammonia is then added to adjust the precipitation pH value of the solution to obtain a niobium salt precipitate with a low antimony content, which can be roasted after solid-liquid separation to obtain a low-antimony niobium oxide product.

[0009] The key to the present invention is to perform peroxide complexation treatment on the fluoniobic acid solution and utilize the difference in solubility between peroxide and non-peroxide of niobium to separate niobium and antimony. Niobium and antimony in the fluoniobic acid solution (niobium solution under acidic conditions and the presence of fluoride ions) are mainly in the form of NbOF5 2- 、SbF7 2- 、SbF6 - When peroxide ions are introduced (through peroxide), the niobium oxyfluoride complex anion (NbOF5 2- ) begins to transform into niobium peroxide complex anions such as Nb(O2)F5 2- 、Nb(O2)2F4 3- etc., while antimony is still in the form of fluorine antimony complex anion (SbF6 - ) form. Because the solubility of peroxoniobate is limited by the steric hindrance and decomposition tendency of the peroxide group, it has a lower solubility than fluoroniobate. When neutralized and crystallized, the peroxoniobate precipitates over a wider pH range and has a higher precipitation rate, while antimony exists only in the form of fluoroantimony complex anions, and its precipitation characteristics are unaffected. Therefore, by pre-treating the fluoroniobate solution with a peroxide complex, niobium in the solution can be preferentially precipitated as peroxoniobate during neutralization and crystallization, while antimony remains in the solution as fluoroantimony complex anions, achieving the purpose of separating niobium and antimony.

[0010] More preferably, the niobium salt precipitate is a peroxoniobate precipitate.

[0011] Preferably, in the fluoroniobic acid solution, the concentration of Nb is 20-80 g / L, the concentration of Sb is 2-50 mg / L, the concentration of hydrogen ions is 4.0-8.0 mol / L, and the concentration of fluoride ions is 1.0-8.0 mol / L.

[0012] Specifically, the fluoroniobic acid solution is a niobium solution produced in the stripping section of the tantalum-niobium metallurgical production process.

[0013] Preferably, the peroxide is at least one of hydrogen peroxide, sodium peroxide, and barium peroxide.

[0014] Peroxide can mainly provide peroxide ions in the solution to achieve the 2- Complexation of ions.

[0015] More preferably, the peroxide is hydrogen peroxide.

[0016] The use of hydrogen peroxide can avoid the introduction of impure metal ions and indirectly improve the purity of subsequent niobium oxide products.

[0017] Preferably, the molar ratio of the peroxide to Nb in the fluoroniobic acid solution is (1-3):1.

[0018] More preferably, the molar ratio of the peroxide to Nb in the fluoroniobic acid solution is (1-1.2):1.

[0019] If the amount of hydrogen peroxide is too low, the niobium complex ions cannot be completely converted into peroxide complex anions; if the amount is too high, the hydrogen peroxide reagent will be wasted.

[0020] Preferably, during the complexation process, the complexation temperature is 5 to 60° C. and the complexation time is 0.5 to 2 hours. Under such complexation conditions, niobium can be fully converted into niobium peroxo complex anions.

[0021] Preferably, the method of adding ammonia includes at least one of introducing ammonia gas, adding ammonia water, adding ammonium carbonate, adding ammonium bicarbonate, and adding carbamide.

[0022] More preferably, the method of adding ammonia is to add aqueous ammonia.

[0023] Preferably, in the process of adding ammonia to adjust the precipitation pH value of the solution: the precipitation pH value of the solution is 7.0-9.0, and the temperature is 5-60°C.

[0024] More preferably, the precipitation pH value of the solution is 7.5 to 8.5.

[0025] In the present invention, the precipitation pH value refers to the pH value of the solution after the precipitation is precipitated by adding ammonia. Furthermore, this pH value is also equivalent to the pH value of the filtrate obtained by filtering after the precipitation is precipitated by adding ammonia.

[0026] If the precipitation pH value of the solution is too low, the niobium precipitation will be incomplete and the recovery rate will be low; if the precipitation pH value is too high, the peroxide ion will be hydrolyzed, reducing the antimony removal effect.

[0027] Preferably, during the calcination process, the calcination temperature is 700-1000° C. and the calcination time is 4-6 hours.

[0028] More preferably, during the calcination process, the calcination temperature is 850° C. and the calcination time is 5 hours.

[0029] Preferably, the antimony content in the low-antimony niobium oxide is below 4 ppm.

[0030] The method of the present invention involves first adding peroxide to a fluoroniobic acid solution and adjusting its concentration without affecting product quality. Ammonia is then added to adjust the solution's pH to preferentially precipitate niobium, resulting in a niobium salt precipitate with a low antimony content. Finally, the precipitate is filtered and calcined to produce low-antimony niobium oxide. The antimony content of the resulting niobium oxide can be reduced to below 4 ppm. The antimony removal method provided by the present invention is simple to operate, has low energy and reagent costs, high antimony removal efficiency, and high product quality, demonstrating promising industrial application prospects.

[0031] Beneficial effects:

[0032] The present invention can achieve deep removal of antimony from a fluoroniobate solution, and the obtained niobium-containing peroxide complex can meet the requirements for preparing 4N-grade high-purity niobium oxide products. The method of the present invention does not require the consumption of expensive special reagents, but only requires the consumption of some peroxide ions, and has low cost, low pollution, and is beneficial to product quality. The entire process is simple to operate, does not require other supporting impurity removal equipment, has low investment, short process flow, and is easy to achieve continuous production. DETAILED DESCRIPTION

[0033] The present invention will be further described below with reference to specific embodiments. The illustrative embodiments and descriptions of the present invention are intended to explain the present invention but are not intended to limit the present invention.

[0034] All raw materials of the present invention are not particularly limited in their sources and can be purchased from the market or prepared according to conventional methods well known to those skilled in the art.

[0035] There is no particular limitation on the purity of all raw materials in the present invention, and the present invention preferably adopts conventional purity used in the art.

[0036] The devices used in the present invention are not particularly limited and can be devices commonly used in the art.

[0037] Example 1

[0038] A method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide comprises the following steps:

[0039] To 40 mL of a fluoroniobate solution (a stripping section antimony-niobium solution provided by a tantalum-niobium smelter, containing 62 g / L Nb, 9.3 mg / L Sb, a hydrogen ion concentration of 6.0 mol / L, and a fluoride ion concentration of 4.2 mol / L) was added hydrogen peroxide for complexation. The molar ratio of hydrogen peroxide to Nb in the fluoroniobate solution was 1:1, the complexation temperature was 25°C, and the complexation time was 1 hour. After complete complexation, 22 mL of concentrated ammonia water was slowly added, and neutralization and precipitation were carried out at room temperature. When a large amount of white crystals precipitated, stirring was stopped, and the solution was filtered. The pH value of the filtrate was measured to be 7.6, and the crystallization rate of the niobium solution was 86.2%. The solution was then dried, and the completely dried niobium solid was oxidatively roasted at a temperature of 850°C for 6 hours to obtain a high-purity niobium oxide product. The antimony content in the niobium oxide was 2.17 ppm, and the antimony removal rate was 98.6%, meeting the requirements for high-purity niobium oxide products.

[0040] Example 2

[0041] A method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide comprises the following steps:

[0042] To 40 mL of a fluoroniobate solution (a stripping section antimony-niobium solution provided by a tantalum-niobium smelter, containing 62 g / L Nb, 9.3 mg / L Sb, a hydrogen ion concentration of 6.0 mol / L, and a fluoride ion concentration of 4.2 mol / L) was added hydrogen peroxide for complexation. The molar ratio of hydrogen peroxide to Nb in the fluoroniobate solution was 1:1, the complexation temperature was 25°C, and the complexation time was 1 hour. After complete complexation, 24 mL of concentrated ammonia water was slowly added, and neutralization and precipitation were carried out at room temperature. When a large amount of white crystals precipitated, stirring was stopped, and the solution was filtered. The pH value of the filtrate was measured to be 8.2, and the crystallization rate of the niobium solution was 90.6%. The solution was then filtered and dried, and the completely dried niobium solid was subjected to oxidative roasting at a temperature of 850°C for 6 hours to obtain a high-purity niobium oxide product.

[0043] The high-purity niobium oxide product obtained in this embodiment was tested to have an antimony content of 4.19 ppm and an antimony removal rate of 97.2%, meeting the requirements for high-purity niobium oxide products.

[0044] Example 3

[0045] A method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide comprises the following steps:

[0046] To 40 mL of a fluoroniobate solution (a stripping section antimony-niobium solution provided by a tantalum-niobium smelter, containing 62 g / L Nb, 9.3 mg / L Sb, a hydrogen ion concentration of 6.0 mol / L, and a fluoride ion concentration of 4.2 mol / L) was added hydrogen peroxide for complexation. The molar ratio of hydrogen peroxide to Nb in the fluoroniobate solution was 1.2:1, the complexation temperature was 25°C, and the complexation time was 1 hour. After complete complexation, 22 mL of concentrated ammonia water was slowly added, and neutralization and precipitation were carried out at room temperature. When a large amount of white crystals precipitated, stirring was stopped, and the solution was filtered. The pH value of the filtrate was measured to be 7.5, and the crystallization rate of the niobium solution was 89.7%. The solution was then dried, and the completely dried niobium solid was subjected to oxidative roasting at a temperature of 850°C for 6 hours to obtain a high-purity niobium oxide product.

[0047] The high-purity niobium oxide product obtained in this embodiment was tested to have an antimony content of 1.84 ppm and an antimony removal rate of 98.8%, meeting the requirements for high-purity niobium oxide products.

[0048] Example 4

[0049] A method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide comprises the following steps:

[0050] To 40 mL of a fluoroniobate solution (a stripping section antimony-niobium solution provided by a tantalum-niobium smelter, containing 62 g / L Nb, 9.3 mg / L Sb, a hydrogen ion concentration of 6.0 mol / L, and a fluoride ion concentration of 4.2 mol / L) was added hydrogen peroxide for complexation. The molar ratio of hydrogen peroxide to Nb in the fluoroniobate solution was 1.5:1, the complexation temperature was 25°C, and the complexation time was 1 hour. After complete complexation, 26 mL of concentrated ammonia water was slowly added, and neutralization and precipitation were carried out at room temperature. When a large amount of white crystals precipitated, stirring was stopped, and the solution was filtered. The pH value of the filtrate was measured to be 8.4, and the crystallization rate of the niobium solution was 96.5%. The solution was then dried, and the completely dried niobium solid was subjected to oxidative roasting at 850°C for 6 hours to obtain a high-purity niobium oxide product.

[0051] The high-purity niobium oxide product obtained in this embodiment was tested to have an antimony content of 3.27 ppm and an antimony removal rate of 97.8%, meeting the requirements for high-purity niobium oxide products.

[0052] Comparative Example 1

[0053] To 40 mL of fluoroniobic acid solution (antimony-containing niobium solution from the stripping section of a tantalum-niobium smelter, containing 62 g / L Nb, 9.3 mg / L Sb, a hydrogen ion concentration of 6.0 mol / L, and a fluoride ion concentration of 4.2 mol / L), 24 mL of concentrated aqueous ammonia was slowly added and neutralized and precipitated at room temperature. When a large amount of white crystals precipitated, stirring was stopped and the solution was filtered. The pH of the filtrate was measured to be 8.3, and the crystallization rate of the niobium solution was 91.3%. The solution was then dried and the completely dried niobium solid was oxidatively roasted at 850°C for 6 hours. The antimony content of the niobium oxide product was measured to be 86.98 ppm, and the antimony removal efficiency was only 41.9%.

[0054] Comparative Example 2

[0055] To 40 mL of a fluoroniobate solution (a stripping section antimony-niobium solution provided by a tantalum-niobium smelter, containing 62 g / L Nb, 9.3 mg / L Sb, a hydrogen ion concentration of 6.0 mol / L, and a fluoride ion concentration of 4.2 mol / L) was added hydrogen peroxide for complexation. The molar ratio of hydrogen peroxide to Nb in the fluoroniobate solution was 1.2:1, the complexation temperature was 25°C, and the complexation time was 1 hour. After complete complexation, 32 mL of concentrated ammonia water was slowly added, and neutralization and precipitation were carried out at room temperature. When a large amount of white crystals precipitated, stirring was stopped, and the solution was filtered. The pH value of the filtrate was measured to be 9.1, and the crystallization rate of the niobium solution was 97.8%. The solution was then dried, and the completely dried niobium solid was subjected to oxidative roasting at 850°C for 6 hours to obtain a niobium oxide product. The antimony content of the niobium oxide product was tested to be 132.11 ppm, and the antimony removal rate was only 11.7%.

[0056] Comparative Example 3

[0057] To 40 mL of a fluoroniobate solution (a stripping section solution containing antimony and niobium provided by a tantalum-niobium smelter, containing 62 g / L Nb, 9.3 mg / L Sb, a hydrogen ion concentration of 4.2 mol / L, and a fluoride ion concentration of 3.6 mol / L) was added hydrogen peroxide for complexation. The molar ratio of hydrogen peroxide to Nb in the fluoroniobate solution was 1:1, and the complexation temperature was 25°C for 1 hour. After complete complexation, 19 mL of concentrated ammonia was slowly added, and neutralization and precipitation occurred at room temperature. When white crystals precipitated, the solution was stirred for a period of time and filtered. The pH of the filtrate was measured to be 7.3, and the crystallization rate of the niobium solution was only 20.5%. The solid was then dried and calcined at 850°C for 6 hours to obtain a niobium oxide product. The antimony content in the niobium oxide was determined to be 1.77 ppm. Although the niobium oxide product met the quality requirements for high-purity niobium oxide, the crystallization rate of the niobium solution was too low, only around 20%, which did not meet production efficiency requirements.

[0058] From the experimental data of Comparative Example 1, it can be seen that when peroxide is not used, the removal rate of antimony is greatly reduced. Therefore, in the method of the present invention, the use of peroxide and the addition of ammonia work synergistically.

[0059] Comparative Example 2 shows that, during the ammonia addition process, when the precipitation pH is too high, the antimony removal rate is significantly reduced. Comparative Document 3 shows that, at lower precipitation pH values, while the antimony removal rate remains relatively high, the niobium liquid crystallization rate is low, failing to meet production requirements. Therefore, during the ammonia addition process, it is preferable to control the precipitation pH between 7.5 and 8.5.

[0060] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. Any technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. A method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide, characterized by: Peroxide is added to a fluoroniobic acid solution for complexation, and then ammonia is added to adjust the precipitation pH value of the solution to obtain a niobium salt precipitate, which is then calcined after solid-liquid separation to obtain low-antimony niobium oxide.

2. The method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide according to claim 1, characterized in that: In the fluoroniobic acid solution, the concentration of Nb is 20-80 g / L, the concentration of Sb is 2-50 mg / L, the concentration of hydrogen ions is 4.0-8.0 mol / L, and the concentration of fluoride ions is 1.0-8.0 mol / L.

3. The method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide according to claim 1, characterized in that: The peroxide is at least one of hydrogen peroxide, sodium peroxide and barium peroxide.

4. The method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide according to claim 1, characterized in that: The molar ratio of the peroxide to Nb in the fluoroniobic acid solution is (1-3):

1.

5. The method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide according to claim 1, characterized in that: During the complexing process, the complexing temperature is 5 to 60° C., and the complexing time is 0.5 to 2 hours.

6. The method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide according to claim 1, characterized in that: The method of adding ammonia includes at least one of introducing ammonia gas, adding ammonia water, adding ammonium carbonate, adding ammonium bicarbonate, and adding carbamide.

7. The method for removing antimony from a fluoniobic acid solution to prepare low-antimony niobium oxide according to claim 1, characterized in that: In the process of adding ammonia to adjust the precipitation pH value of the solution: the precipitation pH value of the solution is 7.0-9.0, and the temperature is 5-60°C.

8. The method for preparing low-antimony niobium oxide by removing antimony from a fluoniobic acid solution according to claim 7, characterized in that: The precipitation pH value of the solution is 7.5-8.

5.

9. The method for preparing low-antimony niobium oxide by removing antimony from a fluoniobic acid solution according to claim 1, characterized in that: During the calcination process, the calcination temperature is 700-1000° C. and the calcination time is 4-6 hours.