Impurity removal method for high-impurity low-concentration acidic vanadium liquid and method for preparing high-purity vanadium

Abstract

The invention provides an impurity removal method for a high-impurity low-concentration acidic vanadium liquid, which comprises the following steps: adjusting the high-impurity low-concentration acidic vanadium liquid to a target acidic range to obtain a first vanadium liquid, the vanadium content in the high-impurity low-concentration acidic vanadium liquid is 25-26 g / L, and the impurity content is 12-14% by mass; and the first vanadium liquid flows through adsorption resin to be subjected to adsorption and impurity removal treatment, second vanadium liquid is obtained, the vanadium content in the second vanadium liquid is 22.5-23.4 g / L, and the impurity content is 0.85-1.55% by mass. The invention further provides a method for preparing high-purity vanadium. The method is simple and efficient, operation is easy to control, the impurity removal rate is high, efficient enrichment of vanadium is achieved, and impurities in the vanadium liquid can be recycled.

Description

Technical Field

[0001] This invention belongs to the field of vanadium metallurgical technology, specifically relating to a method for removing impurities from high-impurity, low-concentration acidic vanadium liquid, and also to a method for preparing high-purity vanadium. Background Technology

[0002] Calcium-based acid leaching of vanadium solution is an acidic liquid obtained by roasting vanadium slag followed by sulfuric acid leaching. Current technology uses a vanadium slag calcification roasting-acid leaching process to extract vanadium and produce ammonium polyvanadate. In the production process, vanadium concentrate is mixed with calcium salts and heated under an oxidizing atmosphere. This process oxidizes low-valent vanadium to high-valent vanadium, which simultaneously reacts with calcium to form calcium vanadate compounds (actually also including calcium manganese vanadate, etc.). During the oxidative calcification roasting process, the oxidation of low-valent vanadium and the oxidative decomposition of additives, along with the calcification reaction of high-valent vanadium with calcium salts, produce acid-soluble calcium vanadate. Subsequently, through the sulfuric acid leaching step, sulfate ions react with calcium to form water-insoluble calcium sulfate, thereby dissolving vanadium into the solution to prepare the calcified acid leaching vanadium solution.

[0003] In vanadium calcination roasting acid leaching solutions, there are a large number of impurity metal ions, especially manganese, magnesium, iron, phosphorus, silicon, and calcium ions. Existing technologies use ordinary solid vanadium products for back dissolution and impurity removal, which is a long process, inefficient, and uneconomical. Extraction methods use large amounts of reagents, are costly, and have complex processes. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a method for removing impurities from high-impurity, low-concentration acidic vanadium solutions, thereby solving the technical problems existing in the re-dissolution and impurity removal of solid vanadium products in the prior art. The present invention also provides a method for preparing high-purity vanadium.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a method for removing impurities from a high-impurity, low-concentration acidic vanadium solution, comprising the following steps: S1. Adjust the high-impurity, low-concentration acidic vanadium solution to the target acidity range to obtain the first vanadium solution, wherein the vanadium content in the high-impurity, low-concentration acidic vanadium solution is 25-26 g / L, and the impurity content is 12-14% by mass percentage; S2. The first vanadium solution is passed through an adsorption resin for adsorption and impurity removal treatment to obtain a second vanadium solution. The vanadium content in the second vanadium solution is 22.5-23.4 g / L, and the impurity content is 0.85-1.55% by mass percentage.

[0006] According to one embodiment of the present invention, in step S1, sulfuric acid is used to adjust the pH value of the high-impurity, low-concentration acidic vanadium solution to 3-4.

[0007] According to an embodiment of the present invention, in step S2, the adsorption and impurity removal process includes the following steps: The first vanadium solution is passed through a pre-adsorption resin for pre-adsorption treatment to obtain the pre-adsorbed first vanadium solution. The pre-adsorbed first vanadium solution is passed through a re-adsorption resin for re-adsorption treatment to obtain a second vanadium solution.

[0008] According to one embodiment of the present invention, The adsorption time for both the pre-adsorption treatment and the re-adsorption treatment is 10-60 min. The amount of the first vanadium solution used is 1-1.5 times the volume of the pre-adsorption resin bed, and the flow rate is 2-3 times the volume of the pre-adsorption resin bed per hour. The amount of the first vanadium solution after pre-adsorption is 1-1.5 times the volume of the re-adsorption resin bed, and the flow rate is 2-3 times the volume of the re-adsorption resin bed per hour.

[0009] According to one embodiment of the present invention, the pre-adsorption resin is a macroporous weakly acidic cation exchange resin; the re-adsorption resin is a macroporous aminocarboxylic acid chelating resin.

[0010] According to one embodiment of the present invention, the method further includes the following steps: After completing the pre-adsorption treatment and the re-adsorption treatment, sulfuric acid is used to elute the pre-adsorption resin and the re-adsorption resin to obtain an acid washing solution. Add the extractant to the pickling solution, mix well, and let stand to separate, obtaining the loaded phase and the aqueous phase; A back-extraction agent is added to the loaded phase for back-extraction to obtain a manganese-containing back-extraction solution.

[0011] According to one embodiment of the present invention, The extraction ratio O / A was 2-5, the extraction temperature was 50-60℃, and the extraction time was 20-30 min. The back-extraction ratio (O / A) is 3-6, the back-extraction temperature is 50-60℃, and the back-extraction time is 20-30 min.

[0012] According to one embodiment of the present invention, The extractant is selected from one of methyl isobutyl ketone, diisopropyl ether, n-octanol, tributyl phosphate, di(2-ethylhexyl) phosphate, 2-ethylhexyl phosphate mono-2-ethylhexyl ester, and bis(2,4,4-trimethylpentyl)phosphonic acid; The back-extraction agent is a mixture of ammonium sulfate solution and sulfuric acid.

[0013] According to one embodiment of the present invention, the method further includes the following steps: After cooling, crystallization, and precipitation, manganese-containing back-extraction solution yields manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals; The obtained manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals were dissolved in water, and ammonium bicarbonate was added. After the reaction, manganese carbonate was obtained. Manganese carbonate is dissolved in dilute sulfuric acid, evaporated, and crystallized to obtain manganese sulfate.

[0014] This invention also provides a method for preparing high-purity vanadium, which uses a second vanadium solution obtained by the above-described impurity removal method to prepare high-purity vanadium, comprising the following steps: The second vanadium solution, after undergoing an ammonium salt precipitation reaction, yields ammonium polyvanadate; The ammonium polyvanadate was calcined to obtain high-purity vanadium powder.

[0015] Compared with the prior art, the beneficial technical effects of the present invention are as follows: (1) This invention addresses the characteristics of high-impurity, low-concentration acidic vanadium solutions, which have low vanadium content, high impurity levels, and are difficult to remove and purify. First, the high-impurity, low-concentration acidic vanadium solution is adjusted to a target acidic range, which is suitable for impurity removal and minimizes vanadium loss. Then, impurities in the high-impurity, low-concentration acidic vanadium solution are adsorbed and removed using an adsorption resin, resulting in efficient separation of vanadium from impurities and obtaining a second vanadium solution (low-impurity vanadium solution). This ultimately achieves the enrichment and removal of low-concentration vanadium. The second vanadium solution undergoes an ammonium salt precipitation reaction and calcination process to obtain high-purity vanadium powder, realizing the comprehensive utilization of vanadium resources.

[0016] (2) The adsorption resin is eluted to obtain an acid washing solution. The acid washing solution is then subjected to extraction-back-extraction treatment to obtain a manganese-containing back-extraction solution. After cooling, crystallization, precipitation and other steps, manganese sulfate is finally obtained from the manganese-containing back-extraction solution, thus achieving the purpose of recovering and utilizing impurities in the vanadium solution.

[0017] (3) The impurity removal method of the present invention is simple, efficient, easy to operate and control, and has a high impurity removal rate. It not only achieves efficient enrichment of vanadium, but also recovers and utilizes impurities in vanadium liquid. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic flowchart of the method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to the present invention. Figure 2 This is another schematic flowchart of the method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to the present invention. Detailed Implementation

[0020] The embodiments of this disclosure will be further described in detail below with reference to the accompanying drawings and examples. The detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of this disclosure by way of example, but should not be used to limit the scope of this disclosure. This disclosure can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0021] These embodiments are provided to make the disclosure thorough and complete, and to fully express the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, material composition, numerical expressions, and values ​​set forth in these embodiments should be interpreted as exemplary only and not as limiting.

[0022] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0023] like Figure 1 As shown, the present invention provides a method for removing impurities from a high-impurity, low-concentration acidic vanadium solution, comprising the following steps: S1. Adjust the high-impurity, low-concentration acidic vanadium solution to the target acidity range to obtain the first vanadium solution, wherein the vanadium content in the high-impurity, low-concentration acidic vanadium solution is 25-26 g / L, and the impurity content is 12-14% by mass percentage.

[0024] S2. The first vanadium solution is passed through an adsorption resin for adsorption and impurity removal treatment to obtain a second vanadium solution. The vanadium content in the second vanadium solution is 22.5-23.4 g / L, and the impurity content is 0.85-1.55% by mass percentage.

[0025] In a preferred embodiment, in step S1, sulfuric acid is used to adjust the pH of the high-impurity, low-concentration acidic vanadium solution to 3-4. This pH range is suitable for impurity removal and minimizes vanadium loss. If the pH is too low or too high, hydrolysis and vanadium precipitation will occur, and some impurities will also precipitate, affecting the impurity removal effect.

[0026] In a preferred embodiment, step S2 includes the following steps: passing a first vanadium solution through a pre-adsorption resin for pre-adsorption treatment to obtain a pre-adsorbed first vanadium solution; and passing the pre-adsorbed first vanadium solution through a re-adsorption resin for re-adsorption treatment to obtain a second vanadium solution.

[0027] In a preferred embodiment, the adsorption time for both the pre-adsorption treatment and the re-adsorption treatment is 10-60 min. The amount of the first vanadium solution used is 1-1.5 times the volume of the pre-adsorption resin bed, and the flow rate is 2-3 times the volume of the pre-adsorption resin bed per hour; the amount of the first vanadium solution after pre-adsorption is 1-1.5 times the volume of the re-adsorption resin bed, and the flow rate is 2-3 times the volume of the re-adsorption resin bed per hour.

[0028] In a preferred embodiment, the pre-adsorption resin is a macroporous weakly acidic cation exchange resin, such as resin D152, resin D151, and resin D113. The re-adsorption resin is a macroporous aminocarboxylic acid chelating resin, such as resin LSC120 and LSC100.

[0029] In a preferred embodiment, the method further includes the following steps: after completing the pre-adsorption and re-adsorption treatments, the pre-adsorption resin and the re-adsorption resin are eluted with sulfuric acid to obtain an acid wash solution. An extractant is added to the acid wash solution, mixed thoroughly, and allowed to stand for separation to obtain a loaded phase and an aqueous phase. A back-extraction agent is added to the loaded phase for back-extraction to obtain a manganese-containing back-extraction solution. Elution of the pre-adsorption resin and the re-adsorption resin allows for recycling and reuse of the pre-adsorption resin and the re-adsorption resin, reducing costs. The pre-adsorption resin D152 of this application can be recycled 3-4 times, and the re-adsorption resin LSC120 can be recycled ≥20 times.

[0030] In a preferred embodiment, the extraction ratio O / A (i.e., the ratio of organic phase volume to aqueous phase volume) is 2-5, the extraction temperature is 50-60°C, and the extraction time is 20-30 min. The back-extraction ratio O / A is 3-6, the back-extraction temperature is 50-60°C, and the back-extraction time is 20-30 min.

[0031] In a preferred embodiment, the extractant is selected from methyl isobutyl ketone, diisopropyl ether, n-octanol, tributyl phosphate, di(2-ethylhexyl) phosphate (P204), 2-ethylhexyl phosphate mono-2-ethylhexyl ester (P507), and bis(2,4,4-trimethylpentyl)phosphonic acid (Cyanex 272). In a preferred embodiment, P204 and P507 are preferred, as P204 and P507 have strong extraction capabilities for most metal ions (low aqueous phase residue) and are particularly effective for divalent metal ions (Mn²⁺). + Ca² + Mg² + It has strong extraction ability. The back-extraction agent is a mixture of ammonium sulfate solution and sulfuric acid. The mass concentration of the ammonium sulfate solution is 10-50 wt.%, the mass concentration of the sulfuric acid solution is 10-30 wt.%, and the mass ratio of ammonium sulfate solution to sulfuric acid is (0.5-1.5):1.

[0032] In a preferred embodiment, the method further includes the following steps: after cooling and crystallizing the manganese-containing back-extraction solution, and then precipitating it, manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals are obtained. The obtained manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals are dissolved in water, and ammonium bicarbonate is added. After reaction, manganese carbonate is obtained. The manganese carbonate is dissolved in dilute sulfuric acid, evaporated, and crystallized to obtain manganese sulfate. Those skilled in the art should understand that manganese sulfate can be prepared from manganese-containing back-extraction solutions using methods known in the prior art, which will not be elaborated here.

[0033] This invention also provides a method for preparing high-purity vanadium. This method uses a second vanadium solution obtained by the above-described impurity removal method to prepare high-purity vanadium, comprising the following steps: the second vanadium solution undergoes an ammonium salt precipitation reaction to obtain ammonium polyvanadate. The ammonium polyvanadate is then calcined to obtain high-purity vanadium powder. Those skilled in the art should understand that ammonium polyvanadate can be prepared from the second vanadium solution using methods known in the prior art, and high-purity vanadium powder can be prepared by calcining ammonium polyvanadate; these methods will not be elaborated upon here.

[0034] The following combination Figure 2 Specific embodiments of the present invention will be described in detail below. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the present invention.

[0035] Table 1 illustrates the components and their contents of the high-impurity, low-concentration acidic vanadium solution of the present invention.

[0036] Table 1. Components and content of high-impurity, low-concentration acidic vanadium solution

[0037] Example 1 (1) Adsorption and impurity removal The pH of the high-impurity, low-concentration acidic vanadium solution was adjusted to 3 using sulfuric acid to obtain the first vanadium solution.

[0038] The first vanadium solution is passed through pre-adsorption resin D152 for pre-adsorption treatment, resulting in a pre-adsorbed first vanadium solution. After pre-adsorption treatment, the pre-adsorption resin is eluted with sulfuric acid to obtain an acid wash solution. The pre-adsorbed first vanadium solution is then passed through re-adsorption resin LSC120 for re-adsorption treatment, resulting in a second vanadium solution. After re-adsorption treatment, the re-adsorption resin is eluted with sulfuric acid to obtain an acid wash solution. This embodiment involves two cycles of pre-adsorption-elution-re-adsorption-elution.

[0039] The pre-adsorption time was 10 min, the volume of the first vanadium solution was 1 times the volume of the pre-adsorption resin bed, and the flow rate was 2 times the volume of the pre-adsorption resin bed per hour. The re-adsorption time was 10 min, the volume of the first vanadium solution after pre-adsorption was 1 times the volume of the re-adsorption resin bed, and the flow rate was 2 times the volume of the re-adsorption resin bed per hour.

[0040] After the above adsorption and impurity removal treatment, the vanadium content in the second vanadium solution is 22.86 g / L, and the impurity content is 1.55% by mass percentage.

[0041] (2) Preparation of manganese sulfate Add an extractant to the pickling solution obtained above, mix thoroughly, and allow to stand to separate, obtaining a loaded phase and an aqueous phase. Add a back-extraction agent to the loaded phase for back-extraction to obtain a manganese-containing back-extraction solution.

[0042] The extractant was P204, with an extraction ratio O / A of 2, an extraction temperature of 50℃, and an extraction time of 20 min. The back-extraction agent was a mixture of 10 wt.% ammonium sulfate solution and 10 wt.% sulfuric acid, with a mass ratio of ammonium sulfate to sulfuric acid of 0.5:1. The back-extraction ratio O / A was 3, the back-extraction temperature was 50℃, and the back-extraction time was 20 min.

[0043] The manganese-containing back-extraction solution was cooled and crystallized at 5°C for 2 hours, followed by precipitation for 0.5 hours to obtain manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals. The obtained manganese ammonium sulfate and magnesium ammonium sulfate crystals were dissolved in water, and ammonium bicarbonate was added. The reaction was maintained at pH 6.5 to obtain manganese carbonate. The manganese carbonate was dissolved in dilute sulfuric acid, evaporated, and crystallized to obtain manganese sulfate.

[0044] Table 2 shows the composition analysis of the prepared manganese sulfate product.

[0045] Table 2. Composition analysis of the prepared manganese sulfate product.

[0046] (3) Preparation of high-purity vanadium The second vanadium solution obtained after adsorption and impurity removal was subjected to an ammonium salt precipitation reaction to obtain ammonium polyvanadate. After calcination at 100℃ for 3 h and 560℃ for 2 h, high-purity vanadium powder was obtained with a vanadium yield of 87.8% and a vanadium grade of 99.70% based on V2O5.

[0047] Example 2 (1) Adsorption and impurity removal The pH of the high-impurity, low-concentration acidic vanadium solution was adjusted to 3.5 using sulfuric acid to obtain the first vanadium solution.

[0048] The first vanadium solution is passed through pre-adsorption resin D151 for pre-adsorption treatment to obtain a pre-adsorbed first vanadium solution. After the pre-adsorption treatment, the pre-adsorption resin is eluted with sulfuric acid to obtain an acid washing solution. The pre-adsorbed first vanadium solution is then passed through re-adsorption resin LSC100 for re-adsorption treatment to obtain a second vanadium solution. After the re-adsorption treatment, the re-adsorption resin is eluted with sulfuric acid to obtain an acid washing solution.

[0049] The pre-adsorption time was 30 min, the volume of the first vanadium solution was 1.2 times the volume of the pre-adsorption resin bed, and the flow rate was 2.5 times the volume of the pre-adsorption resin bed per hour. The re-adsorption time was 30 min, the volume of the first vanadium solution after pre-adsorption was 1.2 times the volume of the re-adsorption resin bed, and the flow rate was 2.5 times the volume of the re-adsorption resin bed per hour.

[0050] After the above adsorption and impurity removal treatment, the vanadium content in the second vanadium solution is 22.87 g / L, and the impurity content is 1.23% by mass percentage.

[0051] (2) Preparation of manganese sulfate Add an extractant to the pickling solution obtained above, mix thoroughly, and allow to stand to separate, obtaining a loaded phase and an aqueous phase. Add a back-extraction agent to the loaded phase for back-extraction to obtain a manganese-containing back-extraction solution.

[0052] The extractant was P507, with an extraction ratio O / A of 4, an extraction temperature of 55℃, and an extraction time of 25 min. The back-extraction agent was a mixture of 25 wt.% ammonium sulfate solution and 12 wt.% sulfuric acid, with a mass ratio of ammonium sulfate to sulfuric acid of 1:1. The back-extraction ratio O / A was 5, the back-extraction temperature was 55℃, and the back-extraction time was 25 min.

[0053] The manganese-containing back-extraction solution was cooled and crystallized at 5°C for 2 hours, followed by precipitation for 0.5 hours to obtain manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals. The obtained manganese ammonium sulfate and magnesium ammonium sulfate crystals were dissolved in water, and ammonium bicarbonate was added. The reaction was maintained at pH 6.5 to obtain manganese carbonate. The manganese carbonate was dissolved in dilute sulfuric acid, evaporated, and crystallized to obtain manganese sulfate.

[0054] Table 3 shows the composition analysis of the prepared manganese sulfate product.

[0055] Table 3. Composition analysis of the prepared manganese sulfate product.

[0056] (3) Preparation of high-purity vanadium The second vanadium solution obtained after adsorption and impurity removal was subjected to an ammonium salt precipitation reaction to obtain ammonium polyvanadate. After calcination at 100℃ for 3 h and 560℃ for 2 h, high-purity vanadium powder was obtained with a vanadium yield of 88.3% and a vanadium grade of 99.93% based on V2O5.

[0057] Example 3 (1) Adsorption and impurity removal The pH of the high-impurity, low-concentration acidic vanadium solution was adjusted to 4 using sulfuric acid to obtain the first vanadium solution.

[0058] The first vanadium solution is passed through pre-adsorption resin D113 for pre-adsorption treatment, yielding a pre-adsorbed first vanadium solution. After pre-adsorption treatment, the pre-adsorption resin is eluted with sulfuric acid to obtain an acid wash solution. The pre-adsorbed first vanadium solution is then passed through re-adsorption resin LSC120 for re-adsorption treatment, yielding a second vanadium solution. After re-adsorption treatment, the re-adsorption resin is eluted with sulfuric acid to obtain an acid wash solution. This embodiment involves two cycles of pre-adsorption-elution-re-adsorption-elution.

[0059] The pre-adsorption time was 60 min, the volume of the first vanadium solution was 1.5 times the volume of the pre-adsorption resin bed, and the flow rate was 3 times the volume of the pre-adsorption resin bed per hour. The re-adsorption time was 60 min, the volume of the first vanadium solution after pre-adsorption was 1.5 times the volume of the re-adsorption resin bed, and the flow rate was 3 times the volume of the re-adsorption resin bed per hour.

[0060] After the above adsorption and impurity removal treatment, the vanadium content in the second vanadium solution is 22.88 g / L, and the impurity content is 0.85% by mass percentage.

[0061] (2) Preparation of manganese sulfate Add an extractant to the pickling solution obtained above, mix thoroughly, and allow to stand to separate, obtaining a loaded phase and an aqueous phase. Add a back-extraction agent to the loaded phase for back-extraction to obtain a manganese-containing back-extraction solution.

[0062] The extractant was Cyanex 272, with an extraction ratio O / A of 5, an extraction temperature of 60℃, and an extraction time of 30 min. The back-extraction agent was a mixture of 50 wt.% ammonium sulfate solution and 30 wt.% sulfuric acid, with a mass ratio of ammonium sulfate to sulfuric acid of 1.5:1. The back-extraction ratio O / A was 6, the back-extraction temperature was 60℃, and the back-extraction time was 30 min.

[0063] The manganese-containing back-extraction solution was cooled and crystallized at 5°C for 2 hours, followed by precipitation for 0.5 hours to obtain manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals. The obtained manganese ammonium sulfate and magnesium ammonium sulfate crystals were dissolved in water, and ammonium bicarbonate was added. The reaction was maintained at pH 6.5 to obtain manganese carbonate. The manganese carbonate was dissolved in dilute sulfuric acid, evaporated, and crystallized to obtain manganese sulfate.

[0064] Table 4 shows the composition analysis of the prepared manganese sulfate product.

[0065] Table 4. Composition analysis of the prepared manganese sulfate product.

[0066] (3) Preparation of high-purity vanadium The second vanadium solution obtained after adsorption and impurity removal was subjected to an ammonium salt precipitation reaction to obtain ammonium polyvanadate. After calcination at 100℃ for 3 h and 560℃ for 2 h, high-purity vanadium powder was obtained with a vanadium yield of 89.2% and a vanadium grade of 99.99% based on V2O5.

[0067] It should be noted that the components or steps in the above embodiments can be interchanged, substituted, added, or deleted. Therefore, the combinations formed by these reasonable permutations and transformations should also fall within the protection scope of this invention, and the protection scope of this invention should not be limited to the above embodiments.

[0068] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples. Within the framework of the invention, technical features of the above embodiments or different embodiments can be combined, and many other variations of the different aspects of the invention as described above exist, which are not provided in the details for the sake of brevity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the protection scope of the invention.

Claims

1. A method for removing impurities from a high-impurity, low-concentration acidic vanadium solution, characterized in that, Includes the following steps: S1. Adjust the high-impurity, low-concentration acidic vanadium solution to the target acidity range to obtain the first vanadium solution, wherein the vanadium content in the high-impurity, low-concentration acidic vanadium solution is 25-26 g / L, and the impurity content is 12-14% by mass percentage; S2. The first vanadium solution is passed through an adsorption resin for adsorption and impurity removal treatment to obtain a second vanadium solution. The vanadium content in the second vanadium solution is 22.5-23.4 g / L, and the impurity content is 0.85-1.55% by mass percentage.

2. The method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to claim 1, characterized in that, In step S1, sulfuric acid is used to adjust the pH of the high-impurity, low-concentration acidic vanadium solution to 3-4.

3. The method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to claim 1, characterized in that, In step S2, the adsorption and impurity removal process includes the following steps: The first vanadium solution is passed through a pre-adsorption resin for pre-adsorption treatment to obtain the pre-adsorbed first vanadium solution. The pre-adsorbed first vanadium solution is passed through a re-adsorption resin for re-adsorption treatment to obtain a second vanadium solution.

4. The method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to claim 3, characterized in that, The adsorption time for both the pre-adsorption treatment and the re-adsorption treatment is 10-60 min. The amount of the first vanadium solution used is 1-1.5 times the volume of the pre-adsorption resin bed, and the flow rate is 2-3 times the volume of the pre-adsorption resin bed per hour. The amount of the first vanadium solution after pre-adsorption is 1-1.5 times the volume of the re-adsorption resin bed, and the flow rate is 2-3 times the volume of the re-adsorption resin bed per hour.

5. The method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to claim 3, characterized in that, The pre-adsorption resin is a macroporous weakly acidic cation exchange resin; the re-adsorption resin is a macroporous aminocarboxylic acid chelating resin.

6. The method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to claim 3, characterized in that, It also includes the following steps: After completing the pre-adsorption treatment and the re-adsorption treatment, sulfuric acid is used to elute the pre-adsorption resin and the re-adsorption resin to obtain an acid washing solution. Add the extractant to the pickling solution, mix well, and let stand to separate, obtaining the loaded phase and the aqueous phase; A back-extraction agent is added to the loaded phase for back-extraction to obtain a manganese-containing back-extraction solution.

7. The method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to claim 6, characterized in that, The extraction ratio O / A was 2-5, the extraction temperature was 50-60℃, and the extraction time was 20-30 min. The back-extraction ratio (O / A) is 3-6, the back-extraction temperature is 50-60℃, and the back-extraction time is 20-30 min.

8. The method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to claim 7, characterized in that, The extractant is selected from one of methyl isobutyl ketone, diisopropyl ether, n-octanol, tributyl phosphate, di(2-ethylhexyl) phosphate, 2-ethylhexyl phosphate mono-2-ethylhexyl ester, and bis(2,4,4-trimethylpentyl)phosphonic acid; The back-extraction agent is a mixture of ammonium sulfate solution and sulfuric acid.

9. The method for removing impurities from a high-impurity, low-concentration acidic vanadium solution according to claim 8, characterized in that, It also includes the following steps: After cooling, crystallization, and precipitation, manganese-containing back-extraction solution yields manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals; The obtained manganese ammonium sulfate crystals and magnesium ammonium sulfate crystals were dissolved in water, and ammonium bicarbonate was added. After the reaction, manganese carbonate was obtained. Manganese carbonate is dissolved in dilute sulfuric acid, evaporated, and crystallized to obtain manganese sulfate.

10. A method for preparing high-purity vanadium, characterized in that, The preparation of high-purity vanadium using the second vanadium solution obtained by the impurity removal method according to any one of claims 1-6 includes the following steps: The second vanadium solution, after undergoing an ammonium salt precipitation reaction, yields ammonium polyvanadate; The ammonium polyvanadate was calcined to obtain high-purity vanadium powder.

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