阅读说明：本技术 从含钒溶液制备钒氧化物的方法 (Method for preparing vanadium oxide from vanadium-containing solution ) 是由 付云枫 刘召波 杜尚超 汪德华 杜国山 孙宁磊 于 2021-08-04 设计创作，主要内容包括：本发明提供了一种从含钒溶液制备钒氧化物的方法。上述方法包括：步骤S1,将含钒溶液的pH值调整至5～11,然后对含钒溶液进行第一萃取,得到萃余液；其中除杂萃取剂为体积浓度5～30％的P204的煤油溶液；步骤S2,向萃余液中加入还原剂进行还原反应,得到还原溶液；步骤S3,对还原溶液进行第二萃取,得到负载钒的有机相；其中钒萃取剂为体积浓度15～35％的P204或P507的煤油溶液；步骤S4,反萃负载钒的有机相,得到反萃溶液；其中反萃剂为盐酸；步骤S5,将反萃溶液进行喷雾热解,得到钒氧化物。本发明解决了现有技术中从含钒溶液中提钒存在的钒氧化物除杂率低、流程长等问题,解决了钒与铬、其他杂质的分离难题。(The invention provides a method for preparing vanadium oxide from vanadium-containing solution. The method comprises the following steps: step S1, adjusting the pH value of the vanadium-containing solution to 5-11, and then carrying out first extraction on the vanadium-containing solution to obtain raffinate; wherein the impurity removal extracting agent is a P204 kerosene solution with the volume concentration of 5-30%; step S2, adding a reducing agent into the raffinate to carry out reduction reaction to obtain a reduction solution; step S3, carrying out second extraction on the reduction solution to obtain a vanadium-loaded organic phase; wherein the vanadium extractant is a kerosene solution of P204 or P507 with the volume concentration of 15-35%; step S4, back extracting the organic phase loaded with vanadium to obtain a back extraction solution; wherein the stripping agent is hydrochloric acid; and step S5, carrying out spray pyrolysis on the stripping solution to obtain vanadium oxide. The method solves the problems of low impurity removal rate of vanadium oxide, long flow and the like in the prior art for extracting vanadium from vanadium-containing solution, and solves the difficult problem of separation of vanadium from chromium and other impurities.)

1. A method of preparing vanadium oxide from a vanadium-containing solution, the cations in the vanadium-containing solution comprising pentavalent vanadium ions, hexavalent chromium ions and impurity ions comprising one or more of sodium ions, calcium ions, ferric ions, silicate ions; characterized in that the method comprises the following steps:

step S1, adjusting the pH value of the vanadium-containing solution to 5-11, and then carrying out first extraction on the vanadium-containing solution by using an impurity-removing extraction agent to obtain a raffinate; the impurity removal extracting agent is a P204 kerosene solution with the volume concentration of 5-30%;

step S2, adding a reducing agent into the raffinate to carry out reduction reaction to obtain a reduction solution;

step S3, performing second extraction on the reduction solution by using a vanadium extraction agent to obtain a vanadium-loaded organic phase; wherein the vanadium extracting agent is a P204 or P507 kerosene solution with the volume concentration of 15-35%;

step S4, back extracting the organic phase loaded with vanadium by using a back extractant to obtain a back extraction solution; wherein the stripping agent is hydrochloric acid;

and step S5, carrying out spray pyrolysis on the stripping solution to obtain the vanadium oxide.

2. The method according to claim 1, wherein in step S1, sodium hydroxide or sulfuric acid is used as a pH adjusting agent for adjusting the pH value of the vanadium-containing solution; preferably, the pH value of the vanadium-containing solution is adjusted to 8-9, and then the first extraction is carried out.

3. The method according to claim 1 or 2, characterized in that in the first extraction process, the extraction phase ratio of O/A is (0.1-1): 1, and countercurrent extraction with 2-4 stages of extraction is adopted; preferably, the impurity removal extracting agent is a P204 sulfonated kerosene solution with the volume concentration of 5-10%.

4. The method according to any one of claims 1 to 3, wherein in the step S2, the reducing agent is at least one of sulfur dioxide, hydrogen sulfide and sodium sulfide, and the temperature of the reduction reaction is 20-98 ℃, preferably 40-98 ℃.

5. The method according to any one of claims 1 to 4, wherein in the step S3, during the second extraction, the extraction ratio O/A is (0.5-4): 1, and the countercurrent extraction with the extraction stages of 8-20 stages is adopted.

6. The method of any one of claims 1 to 4, wherein the vanadium extractant is a sulfonated kerosene solution of P204 or P507 with a volume concentration of 15-35%.

7. The process of any one of claims 1 to 6, wherein in step S4, the vanadium-loaded organic phase is washed with sulfuric acid to obtain an acid wash and a dedust organic phase, and then the dedust organic phase is back-extracted with the stripping agent to obtain the stripping solution;

preferably, a sulfuric acid aqueous solution with the pH of 0.4-1.5 is used in the washing process, and the washing grade is 4-8.

8. The method according to any one of claims 1 to 6, wherein in the step S4, the stripping ratio O/A in the stripping process is 6-20: 1, and countercurrent stripping with 6-20 extraction stages is adopted; preferably, the stripping agent is hydrochloric acid aqueous solution with the concentration of 2-6 mol/L.

9. The method according to claim 1, wherein the vanadium-containing solution is a leaching solution obtained by performing sodium treatment spray pyrolysis and leaching on vanadium slag obtained by smelting vanadium titano-magnetite; preferably, the concentration of vanadium ions in the leachate is 5-90 g/L.

10. The method according to claim 1, wherein in step S5,

controlling the spray pyrolysis process to be in an oxidizing atmosphere, wherein the vanadium oxide is vanadium pentoxide; alternatively, the first and second electrodes may be,

controlling the spray pyrolysis process to be in an inert atmosphere, wherein the vanadium oxide is vanadium dioxide; alternatively, the first and second electrodes may be,

and controlling the spray pyrolysis process to be in a reducing atmosphere, wherein the vanadium oxide is vanadium trioxide.

Technical Field

The invention relates to the technical field of vanadium extraction, in particular to a method for preparing vanadium oxide from a vanadium-containing solution.

Background

In the prior art, the main vanadium extraction raw material is vanadium titano-magnetite, and the vanadium extraction is usually carried out by adopting the following steps: performing sodium treatment roasting on vanadium slag obtained after smelting vanadium titano-magnetite to obtain soluble vanadium slag; leaching soluble vanadium slag (usually water leaching) to obtain a vanadium-containing solution, removing impurities, performing secondary vanadium precipitation to obtain ammonium metavanadate, and finally roasting to obtain vanadium pentoxide. The method has long process flow, low vanadium recovery rate and difficult improvement of product purity. Patent CN101412540A discloses a method for improving product purity by using extraction process, which can improve product purity, but the patent further prolongs the process flow which is not short originally.

The extraction of vanadium from vanadium-containing solution is considered to be an effective method for shortening the process flow, and patent CN109207724A discloses a process for extracting vanadium, specifically, after vanadium and chromium are extracted together by using water-soluble amide as an extractant, the respective back extraction of vanadium and chromium is realized by controlling the back extraction conditions. However, this method is thermodynamically possible, but in practice the separation of vanadium and chromium is not sufficient and another impurity is inevitably present in the single vanadium or chromium product.

Therefore, the vanadium extraction process with short development process and high impurity removal efficiency is an urgent task for reducing the vanadium extraction cost, improving the resource utilization rate and preparing high-quality vanadium oxide products.

Disclosure of Invention

The invention mainly aims to provide a method for preparing vanadium oxide from a vanadium-containing solution, which aims to solve the problems of low impurity removal rate, long flow and the like of vanadium oxide in the prior art of extracting vanadium from the vanadium-containing solution.

In order to achieve the above object, according to one aspect of the present invention, there is provided a method for preparing vanadium oxide from a vanadium-containing solution, cations in the vanadium-containing solution including pentavalent vanadium ions, hexavalent chromium ions, and impurity ions including one or more of sodium ions, calcium ions, ferric ions, silicate ions; the method comprises the following steps: step S1, adjusting the pH value of the vanadium-containing solution to 5-11, and then carrying out first extraction on the vanadium-containing solution by using an impurity-removing extraction agent to obtain raffinate; wherein the impurity removal extracting agent is a P204 kerosene solution with the volume concentration of 5-30%; step S2, adding a reducing agent into the raffinate to carry out reduction reaction to obtain a reduction solution; step S3, performing second extraction on the reduction solution by using a vanadium extractant to obtain a vanadium-loaded organic phase; wherein the vanadium extractant is a kerosene solution of P204 or P507 with the volume concentration of 15-35%; step S4, back extracting the organic phase loaded with vanadium by using a back extractant to obtain a back extraction solution; wherein the stripping agent is hydrochloric acid; and step S5, carrying out spray pyrolysis on the stripping solution to obtain vanadium oxide.

Further, in step S1, sodium hydroxide or sulfuric acid is used as a pH adjuster when adjusting the pH of the vanadium-containing solution; preferably, the pH value of the vanadium-containing solution is adjusted to 8-9, and then the first extraction is carried out.

Furthermore, in the first extraction process, the extraction ratio of O/A is (0.1-1): 1, and countercurrent extraction with 2-4 extraction stages is adopted; preferably, the impurity removal extracting agent is a P204 sulfonated kerosene solution with the volume concentration of 5-10%.

Further, in step S2, the reducing agent is at least one of sulfur dioxide, hydrogen sulfide, and sodium sulfide, and the temperature of the reduction reaction is 20 to 98 ℃, preferably 40 to 98 ℃.

Further, in the step S3, in the second extraction process, the extraction ratio O/A is (0.5-4): 1, and countercurrent extraction with 8-20 stages of extraction is adopted.

Further, the vanadium extracting agent is a P204 or P507 sulfonated kerosene solution with the volume concentration of 15-35%.

Further, in step S4, washing the vanadium-loaded organic phase with sulfuric acid to obtain a pickling solution and an impurity-removed organic phase, and then back-extracting the impurity-removed organic phase with a stripping agent to obtain a back-extraction solution; preferably, a sulfuric acid aqueous solution with the pH of 0.4-1.5 is used in the washing process, and the washing grade is 4-8.

Further, in the step S4, the back extraction ratio O/A in the back extraction process is 6-20: 1, and counter-current back extraction with the extraction stage number of 6-20 is adopted; preferably, the stripping agent is hydrochloric acid aqueous solution with the concentration of 2-6 mol/L.

Further, the vanadium-containing solution is a leaching solution obtained by carrying out sodium treatment, spray pyrolysis and leaching on vanadium slag obtained by smelting vanadium titano-magnetite; preferably, the concentration of vanadium ions in the leaching solution is 5-90 g/L.

Further, in step S5, the spray pyrolysis process is controlled to be in an oxidizing atmosphere, and the vanadium oxide is vanadium pentoxide; or controlling the spray pyrolysis process to be in an inert atmosphere, wherein the vanadium oxide is vanadium dioxide; or controlling the spray pyrolysis process to be in a reducing atmosphere, wherein the vanadium oxide is vanadium trioxide.

According to the method for preparing the vanadium oxide from the vanadium-containing solution, provided by the invention, under the condition of a proper pH value, the vanadium-containing solution is subjected to impurity removal by taking the kerosene solution of P204 with the volume concentration of 5-30% as an impurity removal extracting agent. The step can effectively remove impurity ions, particularly iron ions and calcium ions, in the vanadium-containing solution, and prevent the impurity ions from influencing the subsequent vanadium ion extraction. And in the process, high-valence vanadium ions (+ 5-valence) and high-valence chromium ions (+ 6-valence) can be remained in the solution and are sufficiently separated from impurity ions. Secondly, the present invention can reduce high-valence vanadium ions (+ 5-valent) and high-valence chromium ions (+ 6-valent) to low-valence vanadium ions (+ 4-valent) and low-valence chromium ions (+ 3-valent) by subjecting the raffinate to a reduction reaction, and the low-valence vanadium and chromium ions are more easily separated in the following second extraction process than the high-valence vanadium and chromium ions. According to the invention, the kerosene solution of P204 or P507 with the volume concentration of 15-35% is used as the vanadium extracting agent, so that vanadium ions can be fully extracted into an organic phase, and the vanadium ions and chromium ions are fully separated, thus the purity of the final vanadium oxide is effectively improved, and the yield is high. After the vanadium-loaded organic phase is obtained, hydrochloric acid is used as a stripping agent, so that vanadium ions can be fully stripped from the organic phase to the water phase, and a stripping solution is obtained. Finally, the invention directly carries out spray pyrolysis on the stripping solution to obtain the vanadium oxide. The vanadium ions are fully separated from the chromium ions and other impurity ions by the primary extraction, the secondary extraction and the back extraction processes of the preorder working section, so that a back extraction solution can directly obtain a vanadium oxide product by using a spray pyrolysis mode, the continuous use of a wet extraction process is avoided, and the high-efficiency and high-purity recovery of the vanadium is realized on the basis of shortening the flow. In addition, the invention does not need to adopt an extractant containing ammonia nitrogen, does not generate ammonia nitrogen wastewater, and has wide applicability.

In a word, the method effectively solves the problems of low impurity removal rate, long process and the like of vanadium oxide in the prior art for extracting vanadium from vanadium-containing solution, effectively solves the separation problem of vanadium and chromium, vanadium and other impurities, shortens the lengthy process flow, improves the resource utilization rate, and realizes the preparation of high-purity vanadium oxide products in a short process.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

The invention provides a method for preparing vanadium oxide from a vanadium-containing solution, wherein cations in the vanadium-containing solution comprise pentavalent vanadium ions, hexavalent chromium ions and impurity ions, and the impurity ions comprise one or more of sodium ions, calcium ions, iron ions and silicate ions; the method comprises the following steps: step S1, adjusting the pH value of the vanadium-containing solution to 5-11, and then carrying out first extraction on the vanadium-containing solution by using an impurity-removing extraction agent to obtain raffinate; wherein the impurity removal extracting agent is a kerosene solution of P204 (di (2-ethylhexyl) phosphate) with the volume concentration of 5-30%; step S2, adding a reducing agent into the raffinate to carry out reduction reaction to obtain a reduction solution; step S3, performing second extraction on the reduction solution by using a vanadium extractant to obtain a vanadium-loaded organic phase; wherein the vanadium extractant is a kerosene solution of P204 (di (2-ethylhexyl) phosphate) or P507 (2-ethylhexyl phosphate mono-2-ethylhexyl phosphate) with the volume concentration of 15-35%; step S4, back extracting the organic phase loaded with vanadium by using a back extractant to obtain a back extraction solution; wherein the stripping agent is hydrochloric acid; and step S5, carrying out spray pyrolysis on the stripping solution to obtain vanadium oxide.

According to the method for preparing the vanadium oxide from the vanadium-containing solution, provided by the invention, under the condition of a proper pH value, the vanadium-containing solution is subjected to impurity removal by taking the kerosene solution of P204 with the volume concentration of 5-30% as an impurity removal extracting agent. The step can effectively remove impurity ions, particularly iron ions and calcium ions, in the vanadium-containing solution, and prevent the impurity ions from influencing the subsequent vanadium ion extraction. And in the process, high-valence vanadium ions (+ 5-valence) and high-valence chromium ions (+ 6-valence) can be remained in the solution and are sufficiently separated from impurity ions. Secondly, the present invention can reduce high-valence vanadium ions (+ 5-valent) and high-valence chromium ions (+ 6-valent) to low-valence vanadium ions (+ 4-valent) and low-valence chromium ions (+ 3-valent) by subjecting the raffinate to a reduction reaction, and the low-valence vanadium and chromium ions are more easily separated in the following second extraction process than the high-valence vanadium and chromium ions. According to the invention, the kerosene solution of P204 or P507 with the volume concentration of 15-35% is used as the vanadium extracting agent, so that vanadium ions can be fully extracted into an organic phase, and the vanadium ions and chromium ions are fully separated, thus the purity of the final vanadium oxide is effectively improved, and the yield is high. After the vanadium-loaded organic phase is obtained, hydrochloric acid is used as a stripping agent, so that vanadium ions can be fully stripped from the organic phase to the water phase, and a stripping solution is obtained. Finally, the invention directly carries out spray pyrolysis on the stripping solution to obtain the vanadium oxide. The vanadium ions are fully separated from the chromium ions and other impurity ions by the primary extraction, the secondary extraction and the back extraction processes of the preorder working section, so that a back extraction solution can directly obtain a vanadium oxide product by using a spray pyrolysis mode, the continuous use of a wet extraction process is avoided, and the high-efficiency and high-purity recovery of the vanadium is realized on the basis of shortening the flow. In addition, the invention does not need to adopt an extractant containing ammonia nitrogen, does not generate ammonia nitrogen wastewater, and has wide applicability.

In a word, the method effectively solves the problems of low impurity removal rate, long process and the like of vanadium oxide in the prior art for extracting vanadium from vanadium-containing solution, effectively solves the separation problem of vanadium and chromium, and vanadium and other impurities, and realizes the preparation of high-purity vanadium oxide products in a short process.

It should be noted that in the vanadium-containing solution, the pentavalent vanadium ions are VO₃ ^-In the form of hexavalent chromium ions, CrO₄ ^2-The form exists.

In order to further remove the impurity elements in the vanadium-containing solution, in a preferred embodiment, in step S1, sodium hydroxide or sulfuric acid is used as a pH adjusting agent in adjusting the pH value of the vanadium-containing solution; preferably, the pH value of the vanadium-containing solution is adjusted to 8-9, and then the first extraction is carried out.

In the first extraction process, impurity ions such as iron ions, calcium ions, silicon and the like in the vanadium-containing solution are extracted to an organic phase by using an impurity-removing extracting agent and separated from vanadium and chromium ions in a water phase. In order to further improve the impurity removal effect and simultaneously prevent vanadium and chromium ions from entering an organic phase, in a preferred embodiment, in the first extraction process, the extraction phase ratio O/A is (0.1-1): 1, and countercurrent extraction with the extraction stage number of 2-4 is adopted; preferably, the impurity removal extracting agent is a P204 sulfonated kerosene solution with the volume concentration of 5-10%. O/A here means the volume ratio between the organic phase and the aqueous phase.

In a preferred embodiment, the reducing agent is sulfur dioxide in step S2, and the temperature of the reduction reaction is 20 to 98 ℃, preferably 40 to 98 ℃. The use of sulfur dioxide as a reducing agent enables the above reduction to be accomplished on the one hand and does not introduce additional impurity ions into the system on the other hand. The reduction reaction is more efficient under the above temperature conditions.

After the reduction reaction is finished, the low-valence vanadium ions can be fully separated from the chromium ions in the water phase through a second extraction process, and the vanadium ions enter the organic phase. In order to further improve the extraction effect of vanadium, in a preferred embodiment, in the step S3, in the second extraction process, countercurrent extraction with extraction stages of 8 to 20 stages is adopted, wherein the extraction ratio O/a is (0.5 to 4): 1. More preferably, the vanadium extracting agent is a P204 or P507 sulfonated kerosene solution with the volume concentration of 15-35%.

In a preferred embodiment, in step S4, the vanadium-loaded organic phase is washed with sulfuric acid (for removing impurities) to obtain an acid washing solution and an impurity-removed organic phase, and then the impurity-removed organic phase is back-extracted with a back-extraction agent to obtain a back-extraction solution; preferably, a sulfuric acid aqueous solution with the pH of 0.4-1.5 is used in the washing process, and the washing grade is 4-8.

Hydrochloric acid is used as a stripping agent, so that vanadium ions can be fully stripped from the loaded organic phase to form vanadyl chloride solution (stripping solution). In order to further improve the stripping effect, in a preferred embodiment, in the step S4, the stripping ratio O/a in the stripping process is 6-20: 1, and counter-current stripping with 6-20 extraction stages is adopted; preferably, the stripping agent is hydrochloric acid aqueous solution with the concentration of 2-6 mol/L.

In the specific operation process, a stripping organic phase is also obtained in the stripping process, and preferably, the method further comprises the following steps: regenerating the back extraction organic phase by using a sodium hydroxide aqueous solution to obtain a regenerated organic phase; and (4) returning the regenerated organic phase to the step S3 for preparing the vanadium extractant after acidification. This facilitates recycling of resources. Preferably, the concentration of the sodium hydroxide aqueous solution is 10-160 g/L. In the actual operation process, the sodium hydroxide aqueous solution can be added into the back extraction organic phase for regeneration treatment, and then liquid separation is carried out to obtain a regenerated organic phase. Finally, the vanadium extraction solution is acidified, and the acidified vanadium extraction solution can be returned to the step S3 for preparing the vanadium extractant.

The method is suitable for various vanadium-containing solutions as long as the vanadium-containing solutions contain the impurity ions and the vanadium-chromium ions, and is more suitable for the vanadium extraction process of the leachate obtained by sodium roasting and leaching vanadium slag from vanadium titano-magnetite smelting. Preferably, the concentration of vanadium ions in the leaching solution is 5-90 g/L.

In the spray pyrolysis process, according to different reaction atmospheres, corresponding vanadium oxides can be formed, specifically as follows: controlling the spray pyrolysis process to be in an oxidizing atmosphere, wherein the vanadium oxide is vanadium pentoxide; or controlling the spray pyrolysis process to be in an inert atmosphere (nitrogen atmosphere or argon atmosphere), wherein the vanadium oxide is vanadium dioxide; alternatively, the spray pyrolysis process is controlled to be in a reducing atmosphere (such as hydrogen, methane, carbon monoxide, etc.), and the vanadium oxide is vanadium trioxide. In the specific operation process, the temperature of spray pyrolysis is preferably controlled to be 400-980 ℃ so as to further improve the pyrolysis efficiency.

In summary, the present invention has the following beneficial effects:

1. the extraction process is adopted to replace the traditional impurity removal, vanadium precipitation and melting deamination process, so that the process flow is greatly shortened;

2. the short flow shortens the process links and reduces the vanadium loss of each process link caused by the problem of reaction efficiency;

3. the short process reduces the equipment investment and the production cost.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.

The vanadium-containing solutions in the following examples are all sodium roasting leachate of vanadium slag, the pH value of the solution is 10.2, and the main chemical components of the solution are shown in Table 1.

TABLE 1 sodium salt roasting of vanadium slag, leachate major chemistry (g/L)

V(VO3 -)	Cr(CrO4 2-)	Si(SiO3 2-)	Na+	Ca2+(mg/L)	Fe3+(mg/L)
						46.2	6.1	3.0	42.8	40	13

Note: the element existence form is shown in parentheses.

Example 1

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 9 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/sulfonated kerosene solution with the volume concentration of 6% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.1% and 99.4% respectively.

Introducing enough SO into raffinate at the temperature of 45 DEG C₂Reducing the high valence ions to obtain a reduction solution.

P204/sulfonated kerosene solution with the volume concentration of 28% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1.2:1, and after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, the vanadium content in the raffinate is 25mg/L, and the extraction recovery rate of vanadium is more than 99%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8%, and the concentration of vanadium in the back extraction solution is 140 g/L.

And (3) carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 99.92%, and the total recovery rate of vanadium is 99%.

Example 2

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 9 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the mass concentration of 6% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.8:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.2% and 99.4% respectively.

Introducing enough SO into raffinate at the temperature of 98 DEG C₂Reducing the high-valence compounds to obtain a reduction solution.

P204/kerosene solution with the mass concentration of 28% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1:1, after 20-stage countercurrent extraction, the vanadium content in raffinate is 23mg/L, and the extraction recovery rate of vanadium is more than 99%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.9 percent, and the concentration of vanadium in the back extraction solution is 144 g/L.

And carrying out spray pyrolysis on the stripping solution in nitrogen to obtain a vanadium dioxide product, wherein the purity of the product is 99.93%, and the total recovery rate of vanadium is 98.9%.

Example 3

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 9 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the mass concentration of 6% as an impurity removal extracting agent. The specific extraction ratio O/A is 1:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.3% and 99.5%, respectively.

Introducing enough SO into raffinate at the temperature of 60 DEG C₂Reducing the high-valence compounds to obtain a reduction solution.

P204/kerosene solution with the mass concentration of 28% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1.5:1, after 20-stage countercurrent extraction, the vanadium content in raffinate is 23mg/L, and the extraction recovery rate of vanadium is more than 99%.

Carrying out 4-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.4, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 6mol/L, wherein the ratio of O/A in the back extraction process is 6:1, and the number of back extraction stages is 10, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8 percent, and the concentration of vanadium in the back extraction solution is 104 g/L.

And carrying out spray pyrolysis on the stripping solution in a reducing atmosphere to obtain a vanadium trioxide product, wherein the purity of the product is 99.92%, and the total recovery rate of vanadium is 98.8%.

Example 4

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 11 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the volume concentration of 30% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99% and 99.1% respectively.

Introducing enough SO into raffinate at the temperature of 45 DEG C₂Reducing the high valence ions to obtain a reduction solution.

P204/kerosene solution with the mass concentration of 28% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1:1, and after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, the vanadium content in the raffinate is 20mg/L, and the extraction recovery rate of vanadium is more than 99%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8%, and the concentration of vanadium in the back extraction solution is 140 g/L.

And carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 99.86%, and the total recovery rate of vanadium is 99.1%.

Example 5

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 5 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the mass concentration of 5% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.3% and 99.4% respectively.

Introducing enough SO into raffinate at the temperature of 45 DEG C₂Reducing the high valence ions to obtain a reduction solution.

P204/kerosene solution with the mass concentration of 25% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1.2:1, and after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, wherein the vanadium content in the raffinate is 19mg/L, and the extraction recovery rate of vanadium is 99.3%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8 percent, and the concentration of vanadium in the back extraction solution is 135 g/L.

And (3) carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 99.91%, and the total recovery rate of vanadium is 99.1%.

Example 6

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 8 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the mass concentration of 10% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.4% and 99.5%, respectively.

Introducing enough SO into raffinate at the temperature of 45 DEG C₂Reducing the high valence ions to obtain a reduction solution.

P204/kerosene solution with the mass concentration of 28% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1.2:1, and after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, wherein the vanadium content in the raffinate is 22mg/L, and the extraction recovery rate of vanadium is 99.4%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8 percent, and the concentration of vanadium in the back extraction solution is 139 g/L.

And (3) carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 99.96%, and the total recovery rate of vanadium is 99.2%.

Example 7

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 9 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the volume concentration of 6% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.1% and 99.4% respectively.

Introducing enough SO into raffinate at the temperature of 45 DEG C₂Reducing the high valence ions to obtain a reduction solution.

P204/kerosene solution with the volume concentration of 15% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 4:1, and after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, wherein the vanadium content in the raffinate is 5mg/L, and the extraction recovery rate of vanadium is 99%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8%, and the concentration of vanadium in the back extraction solution is 140 g/L.

And carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 99.92%, and the total recovery rate of vanadium is 98.9%.

Example 8

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 9 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the volume concentration of 6% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.1% and 99.4% respectively.

Introducing enough SO into raffinate at the temperature of 45 DEG C₂Reducing the high valence ions to obtain a reduction solution.

P204/kerosene solution with the volume concentration of 35% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 0.5:1, and after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, wherein the vanadium content in the raffinate is 28mg/L, and the extraction recovery rate of vanadium is 99.4%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8%, and the concentration of vanadium in the back extraction solution is 140 g/L.

And carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 99.92%, and the total recovery rate of vanadium is 99.2%.

Example 9

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 9 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the volume concentration of 6% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.1% and 99.4% respectively.

Introducing enough SO into raffinate at the temperature of 45 DEG C₂Reducing the high valence ions to obtain a reduction solution.

P507/kerosene solution with the volume concentration of 28% is used as a vanadium extracting agent to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1.2:1, after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, the vanadium content in the raffinate is 18mg/L, and the extraction recovery rate of vanadium is 99.3%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8%, and the concentration of vanadium in the back extraction solution is 140 g/L.

And (3) carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 99.92%, and the total recovery rate of vanadium is 99.1%.

Example 10

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 9 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the volume concentration of 6% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.1% and 99.4% respectively.

Introducing enough SO into raffinate at the temperature of 45 DEG C₂Reduce high in itAnd (4) valence ions to obtain a reduction solution.

P204/kerosene solution with the volume concentration of 28% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1.2:1, and after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, wherein the vanadium content in the raffinate is 25mg/L, and the extraction recovery rate of vanadium is 99.1%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 6mol/L, wherein the ratio of O/A in the back extraction process is 8:1, and the number of back extraction stages is 7, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.9 percent, and the concentration of vanadium in the back extraction solution is 142 g/L.

And (3) carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 99.93%, and the total recovery rate of vanadium is 99%.

Comparative example 1

And (3) taking 500mL of the vanadium-containing solution, adjusting the pH to 9 by using dilute sulfuric acid, and extracting to remove iron and calcium by using a P204/kerosene solution with the volume concentration of 6% as an impurity removal extracting agent. The specific extraction ratio O/A is 0.5:1, and after 2-stage countercurrent extraction, raffinate is obtained, and the removal rates of iron and calcium are 99.1% and 99.4% respectively.

And (3) extracting vanadium in the impurity-removed solution by using a P204/kerosene solution with the volume concentration of 28% as a vanadium extracting agent without reducing the raffinate, wherein the specific extraction ratio of O/A is 1.2:1, and obtaining a vanadium-loaded organic phase and a raffinate after 20-stage countercurrent extraction, wherein the content of vanadium in the raffinate is 37g/L, and the extraction recovery rate of vanadium is 19%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8%, and the concentration of vanadium in the back extraction solution is 24 g/L.

And carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 56.24%, and the total recovery rate of vanadium is 18.76%.

Comparative example 2

Taking the vanadium-containing solution 500mL, adjusting the pH to 9 by using dilute sulfuric acid, introducing sufficient SO at the temperature of 45 ℃ without impurity removal and extraction₂Reducing the high valence ions to obtain a reduction solution.

P204/kerosene solution with the volume concentration of 28% is used as a vanadium extractant to extract vanadium in the reduction solution, the specific extraction phase ratio O/A is 1.2:1, and after 20-stage countercurrent extraction, an organic phase loaded with vanadium and raffinate are obtained, the vanadium content in the raffinate is 26mg/L, and the extraction recovery rate of vanadium is more than 99%.

Carrying out 6-stage countercurrent washing on the loaded organic phase by using dilute sulfuric acid with the pH value of 0.8, and then carrying out back extraction on vanadium in the organic phase by using hydrochloric acid with the concentration of 4mol/L, wherein the ratio of O/A in the back extraction process is 10:1, and the number of back extraction stages is 10 stages, so as to obtain a back extraction solution; the back extraction rate of vanadium is 99.8%, and the concentration of vanadium in the back extraction solution is 140 g/L.

And carrying out spray pyrolysis on the stripping solution in the air to obtain a vanadium pentoxide product, wherein the purity of the product is 91.92%, and the total recovery rate of vanadium is 98.8%.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.