Method for preparing vanadium pentoxide by using high-acidity vanadium-containing solution

Abstract

The invention relates to a method for preparing vanadium pentoxide by using a high-acidity vanadium-containing solution. According to the technical scheme, the method comprises the following steps: mixing octyl hydroxamic acid and a high-acidity vanadium-containing solution according to the molar ratio of vanadium to octyl hydroxamic acid in the high-acidity vanadium-containing solution of 1: (0.5-4) to obtain an extraction stock solution; and carrying out positive extraction mixing reaction on the organic extraction agent and the extraction stock solution according to the volume ratio of the organic extraction agent to the extraction stock solution of 1: (1-5), and carrying out phase splitting to obtain the vanadium-containing loaded organic phase and raffinate. Adjusting the pH value of the hydrogen peroxide solution to 0-4 by using a sulfuric acid solution to prepare a stripping agent; and mixing the stripping agent and the vanadium-containing loaded organic phase according to the volume ratio of the stripping agent to the vanadium-containing loaded organic phase of 1: (1-6), and carrying out stripping and phase splitting to obtain vanadium-rich liquid and a lean organic phase. And heating the vanadium-rich solution to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and calcining the vanadium precipitate at a high temperature to obtain V2O5 prepared from the high-acidity vanadium-containing solution. The method solves the problem of generation of neutralization slag and ammonia nitrogen wastewater, and the prepared V2O5 is high in purity.

Description

Technical Field

[0001] The invention belongs to the technical field of vanadium pentoxide and specifically relates to a method for preparing vanadium pentoxide by using a high-acidity vanadium-containing solution. Background Art

[0002] Vanadium shale is an important vanadium reserve resource in China and the main raw material for obtaining vanadium pentoxide. At present, acid leaching is the main process for extracting vanadium from vanadium shale, but the leaching process is not selective, and the obtained acid leaching solution has the characteristics of high acidity and many impurities. Therefore, the purification and enrichment of the acid leaching solution is a key step in obtaining pure vanadium products. P204 solvent extraction is the main process for vanadium extraction, which currently has the following problems: (1) The optimal extraction pH value is 1.8-2.2. Therefore, before extraction, it is necessary to use alkaline agents such as calcium hydroxide and sodium hydroxide to neutralize the high-acidity vanadium-containing leaching solution. The neutralization process will produce a large amount of solid waste such as calcium sulfate, which is difficult to clean and causes pipeline blockage. (2) The obtained vanadium-rich solution is subjected to ammonium salt precipitation of vanadium, which consumes a large amount of ammonia water and produces a large amount of ammonia nitrogen wastewater.

[0003] The patented technology of "Vanadium Extraction Process" (CN 107245586 B) prepares V2O5 products through leaching, reduction, saponification of P204, pH adjustment, extraction, stripping, vanadium precipitation and calcination. The raffinate is extracted again to improve the recovery rate of vanadium, and ammonium salt is used to precipitate vanadium. After washing and roasting, the final purity of V2O5 product is >99%. This technology successfully produces high-purity V2O5, but the preparation process is long and the consumption of alkali reagents is high.

[0004] The patented technology of "A method for preparing vanadium pentoxide by ammonium-free vanadium precipitation" (CN 111020233 B) uses a reducing agent to reduce the vanadium-containing acid leaching solution, and then uses ammonia water to adjust the pH of the solution and then uses a cationic extractant to extract, thereby obtaining an organic phase and a raffinate loaded with vanadium oxycations. The stripping is carried out using hydrogen peroxide and sulfuric acid as stripping agents to obtain a vanadium stripping solution, and then the hydrolysis instability of hydrogen peroxide is used to precipitate vanadium to obtain a vanadium product. This technology avoids the generation of ammonia nitrogen wastewater during the vanadium precipitation process, but ammonia water is used to adjust the pH in the extraction stage, which produces a raffinate wastewater containing ammonia nitrogen, and fails to completely avoid the generation of ammonia nitrogen wastewater.

[0005] The patented technology of "a method for preparing vanadium pentoxide by heating hydrolysis and roasting" (CN 117509731 A) uses an acidic extractant to extract vanadium from a vanadium-containing liquid, and the obtained loaded organic phase is stripped with hydrogen peroxide to obtain a vanadium-rich stripping solution. The stripping solution is heated and hydrolyzed to produce a dark green hydrolysis product, hydrated vanadium oxide. The hydrated vanadium oxide is washed with water to remove impurities in the solid, and the final V2O5 product is roasted after filtering. This solution shortens the hydrolysis and precipitation time of vanadium, and the purity of the prepared V2O5 is greater than 99%, but the purity does not reach 99.5%.

[0006] In summary, the process of preparing V2O5 from high-acidity vanadium-containing solution is long, and the production of neutralization slag and ammonia nitrogen wastewater is difficult to avoid at the same time, and the purity of the V2O5 product is low. Summary of the invention

[0007] The present invention aims to overcome the existing technical defects and aims to provide a method for preparing vanadium pentoxide from a high-acidity vanadium-containing solution, which has a simple process, is clean and environmentally friendly, has low consumption of alkaline reagents, can reduce the generation of neutralization slag and can achieve the goal of generating no ammonia nitrogen wastewater. The vanadium pentoxide prepared by this method has high purity.

[0008] To achieve the above purpose, the specific steps of the technical solution adopted by the present invention are:

[0009] Step 1: Extraction

[0010] The octyl hydroxamic acid and the high-acidity vanadium-containing solution are mixed at a ratio of 1:0.5-4 of the amount of vanadium in the high-acidity vanadium-containing solution: the amount of octyl hydroxamic acid to obtain an extraction stock solution; then, the organic extractant and the extraction stock solution are subjected to a positive extraction mixing reaction at a volume ratio of 1:1-5 of the organic extractant: the extraction stock solution, and phase separation is performed to obtain a vanadium-loaded organic phase and a raffinate.

[0011] Step 2: Stripping

[0012] The pH value of the hydrogen peroxide solution is adjusted to 0-4 with a sulfuric acid solution to prepare a stripping agent; then the stripping agent and the vanadium-loaded organic phase are mixed at a volume ratio of the stripping agent to the vanadium-loaded organic phase of 1:1-6, stripped, and phase-separated to obtain a vanadium-rich solution and a lean organic phase.

[0013] Step 3: Vanadium precipitation

[0014] The vanadium-rich solution is heated to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and then the vanadium precipitate is calcined at high temperature to obtain vanadium pentoxide prepared by using a high-acidity vanadium-containing solution.

[0015] The pH value of the high-acidity vanadium-containing solution is 0.4-1.0.

[0016] In the organic extractant, the phosphonic acid extractant P204 accounts for 10-30% of the total volume, the phase regulator accounts for 1-5% of the total volume, and the rest is No. 260 solvent oil; the phase regulator is one of TBP and octanol.

[0017] The positive extraction mixed reaction is stirred for 10 to 30 minutes at a temperature of 25 to 50° C. and a rotation speed of 300 to 600 r / min.

[0018] The volume concentration of the hydrogen peroxide is 1-10%.

[0019] The stripping process has the following steps: temperature of 25 to 50° C., rotation speed of 300 to 600 r / min, and time of 1 to 10 min.

[0020] The heating vanadium precipitation is carried out by stirring for 30 to 60 minutes at a temperature of 70 to 100° C. and a rotation speed of 300 to 600 r / min.

[0021] The high temperature calcination temperature is 400-600° C., and the high temperature calcination time is 30-120 minutes.

[0022] Due to the adoption of the above technical solution, the present invention has the following positive effects compared with the prior art:

[0023] The present invention does not need to adjust the pH value of the extraction solution, reduces the consumption of alkaline agents such as sodium hydroxide and calcium hydroxide, and avoids the generation of neutralization slag. Octyl hydroxamic acid is used to double coordinate with P204 and vanadium, so that P204 can efficiently extract VO in a solution with a pH of 0.4 to 1.0. 2+ ions. The hydroxamic group has a stronger binding ability to vanadium than the P-OH in P204. The final extraction group is octyl isohydroxamic acid and VO 2+ Combined with P204, vanadium and impurities can be effectively separated at the same time. The process of this method is simple and the consumption of alkaline reagent is low.

[0024] The vanadium precipitation process of the present invention does not use ammonia water, and no ammonia nitrogen wastewater is generated; at the same time, the stripping agent is hydrogen peroxide, a green cleaning agent. The loaded organic phase is stripped with hydrogen peroxide. In an acidic environment, the vanadium exists in the form of H2V 10 O 28 5- The ion forms a peroxy polyvanadate complex with hydrogen peroxide, which is unstable under strong acidic conditions. It is easy to decompose the vanadium precipitation by heating, and then directly obtain the V2O5 product after calcination. The whole process does not produce ammonia nitrogen wastewater, which is clean and environmentally friendly.

[0025] The present invention proposes a novel process for preparing V2O5 from a high-acidity vanadium-containing solution, which directly uses a high-acidity vanadium-containing acid leaching solution as the extraction raw material, without adjusting the pH value, and the three-stage positive extraction rate is >99%. After the vanadium-rich solution is obtained by hydrogen peroxide stripping, vanadium is directly hydrothermally precipitated, and V2O5 with a purity of >99.5% is obtained after calcination. The V2O5 prepared from the high-acidity vanadium-containing solution has high purity.

[0026] The invention is tested: after 2-3 levels of positive extraction, the positive extraction rate is greater than 99%, and the purity of vanadium pentoxide prepared by using high-acidity vanadium-containing solution is greater than 99.5%.

[0027] Therefore, the present invention has the characteristics of simple process, clean and environmentally friendly, low consumption of alkaline reagents, reducing the generation of neutralization slag and realizing ammonium-free vanadium precipitation, and the vanadium pentoxide prepared by the high-acidity vanadium-containing solution has high purity. DETAILED DESCRIPTION

[0028] The present invention is further described below in conjunction with specific embodiments, but is not intended to limit the scope of protection thereof:

[0029] A method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution. The method for preparing vanadium pentoxide in this specific embodiment is:

[0030] Step 1: Extraction

[0031] The octyl hydroxamic acid and the high-acidity vanadium-containing solution are mixed at a ratio of 1:0.5-4 of the amount of vanadium in the high-acidity vanadium-containing solution: the amount of octyl hydroxamic acid to obtain an extraction stock solution; then, the organic extractant and the extraction stock solution are subjected to a positive extraction mixing reaction at a volume ratio of 1:1-5 of the organic extractant: the extraction stock solution, and phase separation is performed to obtain a vanadium-loaded organic phase and a raffinate.

[0032] Step 2: Stripping

[0033] The pH value of the hydrogen peroxide solution is adjusted to 0-4 with a sulfuric acid solution to prepare a stripping agent; then the stripping agent and the vanadium-loaded organic phase are mixed at a volume ratio of the stripping agent to the vanadium-loaded organic phase of 1:1-6, stripped, and phase-separated to obtain a vanadium-rich solution and a lean organic phase.

[0034] Step 3: Vanadium precipitation

[0035] The vanadium-rich solution is heated to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and then the vanadium precipitate is calcined at high temperature to obtain vanadium pentoxide prepared by using a high-acidity vanadium-containing solution.

[0036] The pH value of the high-acidity vanadium-containing solution is 0.4-1.0.

[0037] In the organic extractant, the phosphonic acid extractant P204 accounts for 10-30% of the total volume, the phase regulator accounts for 1-5% of the total volume, and the rest is No. 260 solvent oil; the phase regulator is one of TBP and octanol.

[0038] The positive extraction mixed reaction is stirred for 10 to 30 minutes at a temperature of 25 to 50° C. and a rotation speed of 300 to 600 r / min.

[0039] The volume concentration of the hydrogen peroxide is 1-10%.

[0040] The stripping process has the following steps: temperature of 25 to 50° C., rotation speed of 300 to 600 r / min, and time of 1 to 10 min.

[0041] The heating vanadium precipitation is carried out by stirring for 30 to 60 minutes at a temperature of 70 to 100° C. and a rotation speed of 300 to 600 r / min.

[0042] The high temperature calcination temperature is 400-600° C., and the high temperature calcination time is 30-120 minutes.

[0043] Example 1

[0044] A method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution. The method for preparing vanadium pentoxide described in this embodiment is:

[0045] Step 1: Extraction

[0046] The octyl hydroxamic acid and the high-acidity vanadium-containing solution are mixed at a ratio of 1:0.5 between the amount of vanadium in the high-acidity vanadium-containing solution and the amount of octyl hydroxamic acid to obtain an extraction stock solution; then, the organic extractant and the extraction stock solution are subjected to a positive extraction mixing reaction at a volume ratio of 1:1 between the organic extractant and the extraction stock solution, and phase separation is performed to obtain a vanadium-loaded organic phase and a raffinate.

[0047] Step 2: Stripping

[0048] The pH of the hydrogen peroxide solution is adjusted to 0 with a sulfuric acid solution to prepare a stripping agent; then the stripping agent and the vanadium-loaded organic phase are mixed at a volume ratio of 1:1, stripped, and separated to obtain a vanadium-rich solution and a lean organic phase.

[0049] Step 3: Vanadium precipitation

[0050] The vanadium-rich solution is heated to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and then the vanadium precipitate is calcined at high temperature to obtain vanadium pentoxide prepared by using a high-acidity vanadium-containing solution.

[0051] The pH value of the high-acidity vanadium-containing solution is 1.0.

[0052] In the organic extractant, the phosphonic acid extractant P204 accounts for 10% of the total volume, the phase regulator accounts for 1% of the total volume, and the rest is No. 260 solvent oil; the phase regulator is TBP.

[0053] The positive extraction mixed reaction is stirred for 10 minutes at a temperature of 50° C. and a rotation speed of 300 r / min.

[0054] The volume concentration of the hydrogen peroxide is 1%.

[0055] The stripping process was performed at a temperature of 50° C., a rotation speed of 300 r / min, and a time of 10 min.

[0056] The heating vanadium precipitation is carried out by stirring for 30 minutes at a temperature of 70° C. and a rotation speed of 300 r / min.

[0057] The high temperature calcination temperature is 400° C., and the high temperature calcination time is 120 min.

[0058] The present embodiment has been tested: after 2-3 levels of normal extraction, the normal extraction rate is 99.02%, and the purity of vanadium pentoxide prepared by using the high-acidity vanadium-containing solution is 99.52%.

[0059] Example 2

[0060] A method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution. The method for preparing vanadium pentoxide described in this embodiment is:

[0061] Step 1: Extraction

[0062] The octyl hydroxamic acid and the high-acidity vanadium-containing solution are mixed at a ratio of 1:1 between the amount of vanadium in the high-acidity vanadium-containing solution and the amount of octyl hydroxamic acid to obtain an extraction stock solution; then, the organic extractant and the extraction stock solution are subjected to a positive extraction mixing reaction at a volume ratio of 1:2 between the organic extractant and the extraction stock solution, and phase separation is performed to obtain a vanadium-loaded organic phase and a raffinate.

[0063] Step 2: Stripping

[0064] The pH value of the hydrogen peroxide solution is adjusted to 1 with a sulfuric acid solution to prepare a stripping agent; then the stripping agent and the vanadium-loaded organic phase are mixed at a volume ratio of 1:2, stripped, and separated to obtain a vanadium-rich solution and a lean organic phase.

[0065] Step 3: Vanadium precipitation

[0066] The vanadium-rich solution is heated to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and then the vanadium precipitate is calcined at high temperature to obtain vanadium pentoxide prepared by using a high-acidity vanadium-containing solution.

[0067] The pH value of the high-acidity vanadium-containing solution is 0.9.

[0068] The phosphonic acid extractant P204 accounts for 15% of the total volume of the organic extractant, the phase regulator accounts for 2% of the total volume, and the rest is No. 260 solvent oil; the phase regulator is 2-octanol.

[0069] The positive extraction mixed reaction is carried out under the conditions of a temperature of 40° C. and a rotation speed of 350 r / min, and stirring for 15 minutes.

[0070] The volume concentration of the hydrogen peroxide is 3%.

[0071] The stripping process was performed at a temperature of 45° C., a rotation speed of 350 r / min, and a time of 8 min.

[0072] The heating vanadium precipitation is carried out by stirring for 40 minutes at a temperature of 80° C. and a rotation speed of 350 r / min.

[0073] The high temperature calcination temperature is 450° C., and the high temperature calcination time is 100 min.

[0074] The present embodiment has been tested: after 2-3 levels of normal extraction, the normal extraction rate is 99.25%, and the purity of vanadium pentoxide prepared by using the high-acidity vanadium-containing solution is 99.59%.

[0075] Example 3

[0076] A method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution. The method for preparing vanadium pentoxide described in this embodiment is:

[0077] Step 1: Extraction

[0078] The octyl hydroxamic acid and the high-acidity vanadium-containing solution are mixed at a ratio of 1:2 between the amount of vanadium in the high-acidity vanadium-containing solution and the amount of octyl hydroxamic acid to obtain an extraction stock solution; then, the organic extractant and the extraction stock solution are subjected to a positive extraction mixing reaction at a volume ratio of 1:3 between the organic extractant and the extraction stock solution, and phase separation is performed to obtain a vanadium-loaded organic phase and a raffinate.

[0079] Step 2: Stripping

[0080] The pH value of the hydrogen peroxide solution is adjusted to 2 with a sulfuric acid solution to prepare a stripping agent; then the stripping agent and the vanadium-loaded organic phase are mixed at a volume ratio of 1:3, stripped, and separated to obtain a vanadium-rich solution and a lean organic phase.

[0081] Step 3: Vanadium precipitation

[0082] The vanadium-rich solution is heated to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and then the vanadium precipitate is calcined at high temperature to obtain vanadium pentoxide prepared by using a high-acidity vanadium-containing solution.

[0083] The pH value of the high-acidity vanadium-containing solution is 0.7.

[0084] In the organic extractant, the phosphonic acid extractant P204 accounts for 20% of the total volume, the phase regulator accounts for 3% of the total volume, and the rest is No. 260 solvent oil; the phase regulator is TBP.

[0085] The positive extraction mixed reaction is stirred for 20 minutes at a temperature of 35° C. and a rotation speed of 400 r / min.

[0086] The volume concentration of the hydrogen peroxide is 5%.

[0087] The stripping process was performed at a temperature of 40° C., a rotation speed of 400 r / min, and a time of 6 min.

[0088] The heating vanadium precipitation is carried out by stirring for 45 minutes at a temperature of 85° C. and a rotation speed of 400 r / min.

[0089] The high temperature calcination temperature is 500° C., and the high temperature calcination time is 80 minutes.

[0090] The present embodiment has been tested: after 2-3 levels of normal extraction, the normal extraction rate is 99.69%, and the purity of vanadium pentoxide prepared by using the high-acidity vanadium-containing solution is 99.67%.

[0091] Example 4

[0092] A method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution. The method for preparing vanadium pentoxide described in this embodiment is:

[0093] Step 1: Extraction

[0094] The octyl hydroxamic acid and the high-acidity vanadium-containing solution are mixed at a ratio of 1:3 between the amount of vanadium in the high-acidity vanadium-containing solution and the amount of octyl hydroxamic acid to obtain an extraction stock solution; then, the organic extractant and the extraction stock solution are subjected to a positive extraction mixing reaction at a volume ratio of 1:4 between the organic extractant and the extraction stock solution, and phase separation is performed to obtain a vanadium-loaded organic phase and a raffinate.

[0095] Step 2: Stripping

[0096] The pH value of the hydrogen peroxide solution is adjusted to 3 with a sulfuric acid solution to prepare a stripping agent; then the stripping agent and the vanadium-loaded organic phase are mixed at a volume ratio of 1:5, stripped, and separated to obtain a vanadium-rich solution and a lean organic phase.

[0097] Step 3: Vanadium precipitation

[0098] The vanadium-rich solution is heated to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and then the vanadium precipitate is calcined at high temperature to obtain vanadium pentoxide prepared by using a high-acidity vanadium-containing solution.

[0099] The pH value of the high-acidity vanadium-containing solution is 0.6.

[0100] The phosphonic acid extractant P204 accounts for 25% of the total volume of the organic extractant, the phase regulator accounts for 4% of the total volume, and the rest is No. 260 solvent oil; the phase regulator is 2-octanol.

[0101] The positive extraction mixed reaction is stirred for 25 minutes at a temperature of 30° C. and a rotation speed of 500 r / min.

[0102] The volume concentration of the hydrogen peroxide is 8%.

[0103] The stripping process was performed at a temperature of 30° C., a rotation speed of 500 r / min, and a time of 4 min.

[0104] The heating vanadium precipitation is carried out by stirring for 50 minutes at a temperature of 90° C. and a rotation speed of 500 r / min.

[0105] The high temperature calcination temperature is 550° C., and the high temperature calcination time is 60 minutes.

[0106] The present embodiment has been tested: after 2-3 levels of normal extraction, the normal extraction rate is 99.19%, and the purity of vanadium pentoxide prepared by using the high-acidity vanadium-containing solution is 99.61%.

[0107] Example 5

[0108] A method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution. The method for preparing vanadium pentoxide described in this embodiment is:

[0109] Step 1: Extraction

[0110] The octyl hydroxamic acid and the high-acidity vanadium-containing solution are mixed at a ratio of vanadium substance in the high-acidity vanadium-containing solution to octyl hydroxamic acid at 1:4 to obtain an extraction stock solution; then, the organic extractant and the extraction stock solution are subjected to a positive extraction mixing reaction at a volume ratio of organic extractant to the extraction stock solution at 1:5, and phase separation is performed to obtain a vanadium-loaded organic phase and a raffinate.

[0111] Step 2: Stripping

[0112] The pH value of the hydrogen peroxide solution is adjusted to 4 with a sulfuric acid solution to prepare a stripping agent; then the stripping agent and the vanadium-loaded organic phase are mixed at a volume ratio of 1:6, stripped, and separated to obtain a vanadium-rich solution and a lean organic phase.

[0113] Step 3: Vanadium precipitation

[0114] The vanadium-rich solution is heated to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and then the vanadium precipitate is calcined at high temperature to obtain vanadium pentoxide prepared by using a high-acidity vanadium-containing solution.

[0115] The pH value of the high-acidity vanadium-containing solution is 0.4.

[0116] In the organic extractant, the phosphonic acid extractant P204 accounts for 30% of the total volume, the phase regulator accounts for 5% of the total volume, and the rest is No. 260 solvent oil; the phase regulator is TBP.

[0117] The positive extraction mixed reaction is stirred for 30 minutes at a temperature of 25° C. and a rotation speed of 600 r / min.

[0118] The volume concentration of the hydrogen peroxide is 10%.

[0119] The stripping process was performed at a temperature of 25° C., a rotation speed of 600 r / min, and a time of 1 min.

[0120] The heating vanadium precipitation is carried out by stirring for 60 minutes at a temperature of 100° C. and a rotation speed of 600 r / min.

[0121] The high temperature calcination temperature is 600° C., and the high temperature calcination time is 30 minutes.

[0122] The present embodiment has been tested: after 2-3 levels of normal extraction, the normal extraction rate is 99.11%, and the purity of vanadium pentoxide prepared by using the high-acidity vanadium-containing solution is 99.51%.

[0123] Compared with the prior art, this specific implementation has the following positive effects:

[0124] This specific implementation method does not need to adjust the pH value of the extraction solution, reduces the consumption of alkaline agents such as sodium hydroxide and calcium hydroxide, and avoids the generation of neutralization slag. Octyl hydroxamic acid is used to double coordinate with P204 and vanadium, so that P204 can efficiently extract VO in a solution with a pH of 0.4 to 1.0. 2+ ions. The hydroxamic group has a stronger binding ability to vanadium than the P-OH in P204. The final extraction group is octyl isohydroxamic acid and VO 2+ Combined with P204, vanadium and impurities can be effectively separated at the same time. The process of this method is simple and the consumption of alkaline reagent is low.

[0125] In this specific embodiment, the vanadium precipitation process does not use ammonia water, and no ammonia nitrogen wastewater is generated; at the same time, the stripping agent is hydrogen peroxide, a green cleaning agent. The loaded organic phase is stripped with hydrogen peroxide. In an acidic environment, vanadium exists in the form of H2V 10 O 28 5- The ion forms a peroxy polyvanadate complex with hydrogen peroxide, which is unstable under strong acidic conditions. It is easy to decompose the vanadium precipitation by heating, and then directly obtain the V2O5 product after calcination. The whole process does not produce ammonia nitrogen wastewater, which is clean and environmentally friendly.

[0126] This specific implementation method proposes a new process for preparing V2O5 from a high-acidity vanadium-containing solution, directly using a high-acid vanadium-containing acid leaching solution as the extraction raw material, without adjusting the pH value, and the three-stage positive extraction rate is >99%. After hydrogen peroxide stripping to obtain a vanadium-rich solution, vanadium is directly hydrothermally precipitated, and V2O5 with a purity of >99.5% is obtained after calcination. The V2O5 prepared from a high-acidity vanadium-containing solution has high purity.

[0127] According to the test results of this specific implementation method, after 2-3 levels of positive extraction, the positive extraction rate is greater than 99%, and the purity of vanadium pentoxide prepared by using high-acidity vanadium-containing solution is greater than 99.5%.

[0128] Therefore, this specific implementation method has the characteristics of simple process, clean and environmentally friendly, low consumption of alkaline reagents, reducing the generation of neutralization slag and achieving ammonium-free vanadium precipitation. The vanadium pentoxide prepared by the high-acidity vanadium-containing solution has high purity.

Claims

1. A method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution, characterized in that: The method for preparing vanadium pentoxide is: Step 1: Extraction The octyl hydroxamic acid and the high-acidity vanadium-containing solution are mixed in a ratio of 1:0.5-0.4 between the amount of vanadium in the high-acidity vanadium-containing solution and the amount of octyl hydroxamic acid to obtain an extraction stock solution; then, the organic extractant and the extraction stock solution are subjected to a positive extraction mixing reaction in a volume ratio of 1:1-5 between the organic extractant and the extraction stock solution, and phase separation is performed to obtain a vanadium-loaded organic phase and a raffinate; Step 2: Stripping The pH of the hydrogen peroxide solution is adjusted to 0-4 with a sulfuric acid solution to prepare a stripping agent; then the stripping agent and the vanadium-loaded organic phase are mixed at a volume ratio of 1:1-6, stripped, and separated to obtain a vanadium-rich solution and a lean organic phase; Step 3: Vanadium precipitation The vanadium-rich solution is heated to precipitate vanadium to obtain a vanadium precipitate and a vanadium precipitation mother solution, and then the vanadium precipitate is calcined at high temperature to obtain vanadium pentoxide prepared by using a high-acidity vanadium-containing solution.

2. The method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution according to claim 1, characterized in that: The pH value of the high-acidity vanadium-containing solution is 0.4-1.

0.

3. The method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution according to claim 1, characterized in that: The phosphonic acid extractant P204 accounts for 10-30% of the total volume of the organic extractant, the phase regulator accounts for 1-5% of the total volume, and the rest is No. 260 solvent oil; The phase regulator is one of TBP and octanol.

4. The method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution according to claim 1, characterized in that: The positive extraction mixed reaction is stirred for 10 to 30 minutes at a temperature of 25 to 50° C. and a rotation speed of 300 to 600 r / min.

5. The method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution according to claim 1, characterized in that: The volume concentration of the hydrogen peroxide is 1-10%.

6. The method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution according to claim 1, characterized in that: The stripping process has the following steps: temperature of 25 to 50° C., rotation speed of 300 to 600 r / min, and time of 1 to 10 min.

7. The method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution according to claim 1, characterized in that: The heating vanadium precipitation is carried out by stirring for 30 to 60 minutes at a temperature of 70 to 100° C. and a rotation speed of 300 to 600 r / min.

8. The method for preparing vanadium pentoxide using a high-acidity vanadium-containing solution according to claim 1, characterized in that: The high temperature calcination temperature is 400-600° C., and the high temperature calcination time is 30-120 minutes.