A method for removing antimony from high-purity ammonium metavanadate

Abstract

A method for removing antimony from high-purity ammonium metavanadate comprises the following steps: (1) preparing modified aluminum powder; (2) preparing modified aluminum powder loaded with graphene as a reducing agent; (3) dissolving the raw material ammonium metavanadate in hot water, adding the modified aluminum powder loaded with graphene as a reducing agent obtained in step (3) and sodium nitrate, reacting for more than 30 minutes until no precipitation is produced, and filtering and taking the filtrate after the reaction is completed; (4) adding ammonium metavanadate crystals to the filtrate obtained in step (3) for recrystallization to obtain ammonium metavanadate precipitation, solid-liquid separation, and drying to obtain ammonium metavanadate. The purity of the ammonium metavanadate obtained by the present invention is ≥99.9%, wherein the antimony content is <5ppm. The ammonium metavanadate product obtained by the present invention has stable quality and high production efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical industry, and particularly relates to a method for removing antimony from high-purity ammonium metavanadate. Background Art

[0002] Ammonium metavanadate, with the molecular formula of NH4VO3, is a white or slightly yellowish crystalline powder with a relative density of 2.326 and a molecular weight of 116.98. It is slightly soluble in cold water, hot ethanol and ether, but soluble in hot water and dilute ammonium hydroxide. It turns into vanadium pentoxide when burned in the air.

[0003] Ammonium metavanadate is an intermediate product of vanadium refining. It is mainly used to produce vanadium pentoxide (powder or flake), and then further produce metallic vanadium, ferrovanadium alloy or other vanadium-based alloys. It can also be used as a chemical reagent, catalyst, drying agent, mordant, etc. It is widely used as a glaze in the ceramic industry. With the wide application of ammonium metavanadate in various industries, the requirements for the purity of ammonium metavanadate are getting higher and higher.

[0004] When high-purity ammonium metavanadate contains antimony, it has a great impact on product quality. Therefore, a method for removing antimony from ammonium metavanadate is urgently needed. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a method for removing antimony from high-purity ammonium metavanadate. The ammonium metavanadate obtained by the method has high purity and low antimony content.

[0006] The technical solution adopted by the present invention to solve the technical problem is a method for removing antimony from high-purity ammonium metavanadate, comprising the following steps:

[0007] (1) Preparation of modified aluminum powder: mixing aluminum powder with benzenesulfonic acid equivalent to 1-3% of the weight of the aluminum powder, and dispersing under ultrasonic conditions for more than 30 minutes to obtain modified aluminum powder;

[0008] Furthermore, in step (1), the frequency of ultrasound is 1.2 to 1.5 kHz, and the time of ultrasonic dispersion is 10 to 20 minutes. If the ultrasonic dispersion time is too short, the modified aluminum powder cannot be evenly dispersed, which easily causes the material to agglomerate and the modification effect is not good; if the dispersion time is too long, the morphology of the compound is easily damaged.

[0009] Aluminum powder has good reduction performance, but if it is not modified, it is very easy to react under acidic or alkaline conditions. Studies have shown that the use of benzenesulfonic acid to modify aluminum powder inhibits the reaction performance of aluminum powder under acidic or alkaline conditions, but when it is added to ammonium metavanadate in the subsequent reaction process, it can still maintain good selective reduction performance for impurity metal elements such as antimony, and has good selectivity.

[0010] (2) preparing a reducing agent: mixing the modified aluminum powder obtained in step (1), sodium sulfate, and ammonium chloride in a mass ratio of 1:0.001-0.005:0.02-0.03, adding graphene equivalent to 3-8% of the mass of the modified aluminum powder, and mixing under ultrasonic conditions to obtain a modified aluminum powder loaded with reducing agent graphene;

[0011] Studies have shown that the modified aluminum powder loaded with graphene, a reducing agent prepared by adding sodium sulfate and ammonium chloride, has good selectivity for reducing the antimony element in ammonium metavanadate.

[0012] Furthermore, in step (2), the frequency of ultrasound is 1.0 to 1.2 kHz, and the time of ultrasonic mixing is 5 to 10 minutes. If the ultrasonic mixing time is too short, the graphene cannot be evenly dispersed, which may easily cause material agglomeration; if the ultrasonic mixing time is too long, the graphene morphology may be easily damaged.

[0013] (3) dissolving the raw material ammonium metavanadate in hot water (preferably 50-60° C.), adding the reducing agent graphene-loaded modified aluminum powder and sodium nitrate obtained in step (3), and reacting for more than 30 minutes until no precipitation is produced. The reaction is completed, and the filtrate is filtered to obtain the filtrate;

[0014] The modified aluminum powder particles loaded with the reducing agent graphene prepared by the present invention have consistent morphology and are evenly dispersed, and have a high impurity element loading amount. After reducing the impurity ions, the impurity ions are further adsorbed, which is conducive to the adsorption of impurities, and the reduction and adsorption are completed in one step. Studies have shown that the present invention adds a reducing agent to the vanadium liquid to reduce antimony, generate corresponding compounds, and filter into the impurity slag, and the harmful elements are removed, and the impurity ions such as antimony in ammonium metavanadate can be better removed, and the adsorption of ammonium metavanadate is less. Insoluble impurities such as graphene can be filtered out.

[0015] Furthermore, the amount of sodium nitrate added is equivalent to 0.1-0.2% of the weight of the raw material ammonium metavanadate. Sodium nitrate can help fix the antimony element in the raw material ammonium metavanadate.

[0016] Furthermore, in step (3), the raw material ammonium metavanadate is ammonium metavanadate with a purity of ≥99%. It contains a certain amount of antimony, and generally, the antimony content is <0.3%. If the antimony content in the raw material ammonium metavanadate is too high and the purity of the ammonium metavanadate is too low, the crude ammonium metavanadate can be initially purified by other methods, and then the antimony can be removed by the method of the present invention.

[0017] Furthermore, in step (3), the mass ratio of the raw material ammonium metavanadate to hot water is 0.03-0.08:1.

[0018] (4) adding ammonium metavanadate crystals to the filtrate obtained in step (3) for recrystallization to obtain ammonium metavanadate precipitate, separating the solid from the liquid, and drying to obtain ammonium metavanadate.

[0019] In the step (4) of the present invention, by adding ammonium metavanadate seeds to destroy the supersaturation of the solution during vanadium precipitation, the vanadium precipitation time can be shortened, the contact time between ammonium metavanadate and impurities can be reduced, and the product purity of ammonium metavanadate can be improved without adversely affecting the product purity.

[0020] The purity of the ammonium metavanadate obtained by the invention is ≥99.9%, wherein the content of antimony is <5ppm. The ammonium metavanadate product obtained by the invention has stable quality and high production efficiency.

[0021] The invention purifies ammonium metavanadate, separates harmful elements such as antimony therein, adds a special reducing agent to reduce the harmful elements such as antimony in the ammonium metavanadate to low-price, and then generates corresponding compounds, and obtains a high-purity sodium metavanadate solution after filtering and removing impurities, and further recrystallizes to obtain high-purity ammonium metavanadate. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below in conjunction with specific embodiments. Example 1

[0023] The method for removing antimony from high-purity ammonium metavanadate of this embodiment comprises the following steps:

[0024] (1) Preparation of modified aluminum powder: aluminum powder was mixed with benzenesulfonic acid equivalent to 1% of the weight of aluminum powder, and dispersed under ultrasonic conditions for 30 minutes to obtain modified aluminum powder;

[0025] In step (1), the ultrasonic frequency is 1.5 kHz and the ultrasonic dispersion time is 10 minutes. If the ultrasonic dispersion time is too short, the modified aluminum powder cannot be evenly dispersed, which easily causes the material to agglomerate and the modification effect is not good; if the dispersion time is too long, the compound morphology is easily damaged.

[0026] Aluminum powder has good reduction performance, but if it is not modified, it is very easy to react under acidic or alkaline conditions. Studies have shown that the use of benzenesulfonic acid to modify aluminum powder inhibits the reaction performance of aluminum powder under acidic or alkaline conditions, but when it is added to ammonium metavanadate in the subsequent reaction process, it can still maintain good selective reduction performance for impurity metal elements such as antimony, and has good selectivity.

[0027] (2) preparing a reducing agent: mixing the modified aluminum powder obtained in step (1), sodium sulfate, and ammonium chloride in a mass ratio of 1:0.001:0.03, adding graphene equivalent to 3% of the mass of the modified aluminum powder, and mixing under ultrasonic conditions to obtain a modified aluminum powder loaded with reducing agent graphene;

[0028] Studies have shown that the modified aluminum powder loaded with graphene, a reducing agent prepared by adding sodium sulfate and ammonium chloride, has good selectivity for reducing the antimony element in ammonium metavanadate.

[0029] In step (2), the frequency of ultrasound is 1.0 kHz, and the ultrasonic mixing time is 10 minutes. If the ultrasonic mixing time is too short, the graphene cannot be evenly dispersed, which may easily cause material agglomeration; if the ultrasonic mixing time is too long, the graphene morphology may be easily damaged.

[0030] (3) dissolving the raw material ammonium metavanadate in hot water at 60° C., adding the reducing agent graphene-loaded modified aluminum powder and sodium nitrate obtained in step (3), and reacting for 30 minutes until no precipitation is produced. After the reaction is completed, filtering, and collecting the filtrate;

[0031] The modified aluminum powder particles loaded with the reducing agent graphene prepared by the present invention have consistent morphology and are evenly dispersed, and have a high impurity element loading amount. After reducing the impurity ions, the impurity ions are further adsorbed, which is conducive to the adsorption of impurities, and the reduction and adsorption are completed in one step. Studies have shown that the present invention adds a reducing agent to the vanadium liquid to reduce antimony, generate corresponding compounds, and filter into the impurity slag, and the harmful elements are removed, and the impurity ions such as antimony in ammonium metavanadate can be better removed, and the adsorption of ammonium metavanadate is less. Insoluble impurities such as graphene can be filtered out.

[0032] The amount of sodium nitrate added is equivalent to 0.1% of the weight of the raw material ammonium metavanadate. Sodium nitrate can help fix the antimony element in the raw material ammonium metavanadate.

[0033] In step (3), the raw material ammonium metavanadate is ammonium metavanadate with a purity of 99%. It contains a certain amount of antimony, and the antimony content is 0.2%. If the antimony content in the raw material ammonium metavanadate is too high and the purity of the ammonium metavanadate is too low, it is crude ammonium metavanadate, which can be initially purified by other methods and then the antimony can be removed by the method of the present invention.

[0034] In step (3), the mass ratio of the raw material ammonium metavanadate to hot water is 0.03:1.

[0035] (4) adding ammonium metavanadate crystals to the filtrate obtained in step (3) for recrystallization to obtain ammonium metavanadate precipitate, separating the solid from the liquid, and drying to obtain ammonium metavanadate.

[0036] In the step (4) of the present invention, by adding ammonium metavanadate seeds to destroy the supersaturation of the solution during vanadium precipitation, the vanadium precipitation time can be shortened, the contact time between ammonium metavanadate and impurities can be reduced, and the product purity of ammonium metavanadate can be improved without adversely affecting the product purity.

[0037] The purity of the ammonium metavanadate obtained by the invention is 99.92%, wherein the content of antimony is 3ppm. The ammonium metavanadate product obtained by the invention has stable quality and high production efficiency.

[0038] The invention purifies ammonium metavanadate, separates harmful elements such as antimony therein, adds a special reducing agent to reduce the harmful elements such as antimony in the ammonium metavanadate to low-price, and then generates corresponding compounds, and obtains a high-purity sodium metavanadate solution after filtering and removing impurities, and further recrystallizes to obtain high-purity ammonium metavanadate. Example 2

[0039] The method for removing antimony from high-purity ammonium metavanadate of this embodiment comprises the following steps:

[0040] (1) Preparation of modified aluminum powder: aluminum powder was mixed with benzenesulfonic acid equivalent to 3% of the weight of aluminum powder, and dispersed under ultrasonic conditions for 40 minutes to obtain modified aluminum powder;

[0041] In step (1), the ultrasonic frequency is 1.5 kHz and the ultrasonic dispersion time is 20 minutes. If the ultrasonic dispersion time is too short, the modified aluminum powder cannot be evenly dispersed, which easily causes the material to agglomerate and the modification effect is not good; if the dispersion time is too long, the compound morphology is easily damaged.

[0042] Aluminum powder has good reduction performance, but if it is not modified, it is very easy to react under acidic or alkaline conditions. Studies have shown that the use of benzenesulfonic acid to modify aluminum powder inhibits the reaction performance of aluminum powder under acidic or alkaline conditions, but when it is added to ammonium metavanadate in the subsequent reaction process, it can still maintain good selective reduction performance for impurity metal elements such as antimony, and has good selectivity.

[0043] (2) preparing a reducing agent: mixing the modified aluminum powder obtained in step (1), sodium sulfate, and ammonium chloride in a mass ratio of 1:0.005:0.03, adding graphene equivalent to 8% of the mass of the modified aluminum powder, and mixing under ultrasonic conditions to obtain a modified aluminum powder loaded with reducing agent graphene;

[0044] Studies have shown that the modified aluminum powder loaded with graphene, a reducing agent prepared by adding sodium sulfate and ammonium chloride, has good selectivity for reducing the antimony element in ammonium metavanadate.

[0045] In step (2), the frequency of ultrasound is 1.2 kHz, and the ultrasonic mixing time is 10 minutes. If the ultrasonic mixing time is too short, the graphene cannot be evenly dispersed, which may easily cause material agglomeration; if the ultrasonic mixing time is too long, the graphene morphology may be easily damaged.

[0046] (3) dissolving the raw material ammonium metavanadate in hot water at 50° C., adding the reducing agent graphene-loaded modified aluminum powder and sodium nitrate obtained in step (3), and reacting for 50 minutes until no precipitation is produced. After the reaction is completed, filtering, and collecting the filtrate;

[0047] The modified aluminum powder particles loaded with the reducing agent graphene prepared by the present invention have consistent morphology and are evenly dispersed, and have a high impurity element loading amount. After reducing the impurity ions, the impurity ions are further adsorbed, which is conducive to the adsorption of impurities, and the reduction and adsorption are completed in one step. Studies have shown that the present invention adds a reducing agent to the vanadium liquid to reduce antimony, generate corresponding compounds, and filter into the impurity slag, and the harmful elements are removed, and the impurity ions such as antimony in ammonium metavanadate can be better removed, and the adsorption of ammonium metavanadate is less. Insoluble impurities such as graphene can be filtered out.

[0048] The amount of sodium nitrate added is equivalent to 0.2% of the weight of the raw material ammonium metavanadate. Sodium nitrate can help fix the antimony element in the raw material ammonium metavanadate.

[0049] In step (3), the raw material ammonium metavanadate is ammonium metavanadate with a purity of 99%. It contains a certain amount of antimony, and the antimony content is 0.22%. If the antimony content in the raw material ammonium metavanadate is too high and the purity of the ammonium metavanadate is too low, it is crude ammonium metavanadate, which can be initially purified by other methods and then the antimony can be removed by the method of the present invention.

[0050] In step (3), the mass ratio of the raw material ammonium metavanadate to hot water is 0.08:1.

[0051] (4) adding ammonium metavanadate crystals to the filtrate obtained in step (3) for recrystallization to obtain ammonium metavanadate precipitate, separating the solid from the liquid, and drying to obtain ammonium metavanadate.

[0052] In the step (4) of the present invention, by adding ammonium metavanadate seeds to destroy the supersaturation of the solution during vanadium precipitation, the vanadium precipitation time can be shortened, the contact time between ammonium metavanadate and impurities can be reduced, and the product purity of ammonium metavanadate can be improved without adversely affecting the product purity.

[0053] The purity of the ammonium metavanadate obtained by the invention is 99.95%, wherein the content of antimony is 2ppm. The ammonium metavanadate product obtained by the invention has stable quality and high production efficiency.

[0054] The invention purifies ammonium metavanadate, separates harmful elements such as antimony therein, adds a special reducing agent to reduce the harmful elements such as antimony in the ammonium metavanadate to low-price, and then generates corresponding compounds, and obtains a high-purity sodium metavanadate solution after filtering and removing impurities, and further recrystallizes to obtain high-purity ammonium metavanadate. Example 3

[0055] The method for removing antimony from high-purity ammonium metavanadate of this embodiment comprises the following steps:

[0056] (1) Preparation of modified aluminum powder: aluminum powder was mixed with benzenesulfonic acid equivalent to 2% of the weight of aluminum powder, and dispersed under ultrasonic conditions for 60 minutes to obtain modified aluminum powder;

[0057] In step (1), the ultrasonic frequency is 1.4 kHz and the ultrasonic dispersion time is 15 minutes. If the ultrasonic dispersion time is too short, the modified aluminum powder cannot be evenly dispersed, which easily causes the material to agglomerate and the modification effect is not good; if the dispersion time is too long, the compound morphology is easily damaged.

[0058] Aluminum powder has good reduction performance, but if it is not modified, it is very easy to react under acidic or alkaline conditions. Studies have shown that the use of benzenesulfonic acid to modify aluminum powder inhibits the reaction performance of aluminum powder under acidic or alkaline conditions, but when it is added to ammonium metavanadate in the subsequent reaction process, it can still maintain good selective reduction performance for impurity metal elements such as antimony, and has good selectivity.

[0059] (2) preparing a reducing agent: mixing the modified aluminum powder obtained in step (1), sodium sulfate, and ammonium chloride in a mass ratio of 1:0.004:0.025, adding graphene equivalent to 5% of the mass of the modified aluminum powder, and mixing under ultrasonic conditions to obtain a modified aluminum powder loaded with reducing agent graphene;

[0060] Studies have shown that the modified aluminum powder loaded with graphene, a reducing agent prepared by adding sodium sulfate and ammonium chloride, has good selectivity for reducing the antimony element in ammonium metavanadate.

[0061] In step (2), the frequency of ultrasound is 1.1 kHz and the time of ultrasonic mixing is 8 minutes. If the ultrasonic mixing time is too short, the graphene cannot be evenly dispersed and it is easy to cause material agglomeration; if the ultrasonic mixing time is too long, it is easy to damage the graphene morphology.

[0062] (3) dissolving the raw material ammonium metavanadate in hot water at 60° C., adding the reducing agent graphene-loaded modified aluminum powder and sodium nitrate obtained in step (3), reacting for 40 minutes until no precipitation is produced, filtering and collecting the filtrate;

[0063] The modified aluminum powder particles loaded with the reducing agent graphene prepared by the present invention have consistent morphology and are evenly dispersed, and have a high impurity element loading amount. After reducing the impurity ions, the impurity ions are further adsorbed, which is conducive to the adsorption of impurities, and the reduction and adsorption are completed in one step. Studies have shown that the present invention adds a reducing agent to the vanadium liquid to reduce antimony, generate corresponding compounds, and filter into the impurity slag, and the harmful elements are removed, and the impurity ions such as antimony in ammonium metavanadate can be better removed, and the adsorption of ammonium metavanadate is less. Insoluble impurities such as graphene can be filtered out.

[0064] The amount of sodium nitrate added is equivalent to 0.15% of the weight of the raw material ammonium metavanadate. Sodium nitrate can help fix the antimony element in the raw material ammonium metavanadate.

[0065] In step (3), the raw material ammonium metavanadate is ammonium metavanadate with a purity of 99%. It contains a certain amount of antimony, and the antimony content is 0.2%. If the antimony content in the raw material ammonium metavanadate is too high and the purity of the ammonium metavanadate is too low, it is crude ammonium metavanadate, which can be initially purified by other methods and then the antimony can be removed by the method of the present invention.

[0066] In step (3), the mass ratio of the raw material ammonium metavanadate to hot water is 0.06:1.

[0067] (4) adding ammonium metavanadate crystals to the filtrate obtained in step (3) for recrystallization to obtain ammonium metavanadate precipitate, separating the solid from the liquid, and drying to obtain ammonium metavanadate.

[0068] In the step (4) of the present invention, by adding ammonium metavanadate seeds to destroy the supersaturation of the solution during vanadium precipitation, the vanadium precipitation time can be shortened, the contact time between ammonium metavanadate and impurities can be reduced, and the product purity of ammonium metavanadate can be improved without adversely affecting the product purity.

[0069] The purity of the ammonium metavanadate obtained by the invention is 99.96%, wherein the content of antimony is 3ppm. The ammonium metavanadate product obtained by the invention has stable quality and high production efficiency.

[0070] The invention purifies ammonium metavanadate, separates harmful elements such as antimony therein, adds a special reducing agent to reduce the harmful elements such as antimony in the ammonium metavanadate to low-price, and then generates corresponding compounds, and obtains a high-purity sodium metavanadate solution after filtering and removing impurities, and further recrystallizes to obtain high-purity ammonium metavanadate.

[0071] Comparative Example 1

[0072] In this comparative example, except that the aluminum powder is not modified with benzenesulfonic acid, other operations are exactly the same as those in Example 1. The purity of the ammonium metavanadate obtained in this comparative example is 99.20%, wherein the antimony content is 0.1%.

[0073] Comparative Example 2

[0074] In this comparative example, in step (1), ordinary mixing is used instead of ultrasonic dispersion, and other operations are exactly the same as those in Example 1. The purity of the ammonium metavanadate obtained in this comparative example is 99.35%, wherein the antimony content is 0.04%.

[0075] Comparative Example 3

[0076] In this comparative example, sodium sulfate was not added in step (2), and other operations were exactly the same as those in Example 1. The purity of the ammonium metavanadate obtained in this comparative example was 99.35%, and the antimony content was 0.07%.

[0077] Comparative Example 4

[0078] In this comparative example, in step (2), ammonium chloride was not added, and the other operations were exactly the same as those in Example 1. The purity of the ammonium metavanadate obtained in this comparative example was 99.52%, wherein the antimony content was 0.02%.

[0079] Comparative Example 5

[0080] In this comparative example, in step (2), graphene was not added, and the other operations were exactly the same as those in Example 1. The purity of the ammonium metavanadate obtained in this comparative example was 99.20%, and the antimony content was 0.06%.

Claims

1. A method for removing antimony from high-purity ammonium metavanadate, characterized in that: The following steps are involved: (1) Preparation of modified aluminum powder: mixing aluminum powder with benzenesulfonic acid equivalent to 1-3% of the weight of the aluminum powder, and dispersing under ultrasonic conditions for more than 30 minutes to obtain modified aluminum powder; (2) preparing a reducing agent: mixing the modified aluminum powder obtained in step (1), sodium sulfate, and ammonium chloride in a mass ratio of 1:0.001-0.005:0.02-0.03, adding graphene equivalent to 3-8% of the mass of the modified aluminum powder, and mixing under ultrasonic conditions to obtain a modified aluminum powder loaded with reducing agent graphene; (3) dissolving the raw material ammonium metavanadate in hot water, adding the reducing agent graphene-loaded modified aluminum powder and sodium nitrate obtained in step (2), reacting for more than 30 minutes until no precipitation is produced, the reaction is completed, filtering, and collecting the filtrate; (4) adding ammonium metavanadate crystals to the filtrate obtained in step (3) for recrystallization to obtain ammonium metavanadate precipitate, separating the solid from the liquid, and drying to obtain ammonium metavanadate.

2. The method for removing antimony from high-purity ammonium metavanadate according to claim 1, characterized in that: In step (1), the frequency of ultrasound is 1.2 to 1.5 kHz, and the time of ultrasonic dispersion is 10 to 20 minutes.

3. The method for removing antimony from high-purity ammonium metavanadate according to claim 1 or 2, characterized in that: In step (2), the frequency of ultrasound is 1.0 to 1.2 kHz, and the time of ultrasonic mixing is 5 to 10 minutes.

4. The method for removing antimony from high-purity ammonium metavanadate according to claim 1 or 2, characterized in that: In step (3), the raw material ammonium metavanadate is dissolved in hot water at 50-60°C.

5. The method for removing antimony from high-purity ammonium metavanadate according to claim 1 or 2, characterized in that: In step (3), the amount of sodium nitrate added is equivalent to 0.1-0.2% by weight of the raw material ammonium metavanadate.

6. The method for removing antimony from high-purity ammonium metavanadate according to claim 1 or 2, characterized in that: In step (3), the raw material ammonium metavanadate is ammonium metavanadate with a purity of ≥99%.

7. The method for removing antimony from high-purity ammonium metavanadate according to claim 1 or 2, characterized in that: In step (3), the antimony content in the raw material ammonium metavanadate is less than 0.3%.

8. The method for removing antimony from high-purity ammonium metavanadate according to claim 1 or 2, characterized in that: In step (3), the mass ratio of the raw material ammonium metavanadate to hot water is 0.03-0.08:1.