Method for preparing vanadium oxide by using manganese-containing acidic vanadium liquid

Abstract

The invention discloses a method for preparing vanadium oxide by using manganese-containing acidic vanadium liquid, which comprises the following steps: S1, adjusting the manganese-containing acidic vanadium liquid to a preset pH value, stirring to react for t1 under the condition of T1, and carrying out solid-liquid separation to obtain a first vanadium precipitate; s2, adding the first vanadium precipitate into an alkaline solution, heating to T2, stirring to react for t2, and carrying out solid-liquid separation to obtain a vanadium-containing solution and manganese-containing waste slag; s3, cooling the vanadium-containing solution to T3, slowly stirring to react for t3, and carrying out solid-liquid separation to obtain a second vanadium precipitate and supernatant; and S4, oxidizing and calcining the second vanadium precipitate under the condition of T4 to obtain a vanadium oxide product, supplementing the alkaline solution into the supernatant, and returning to the step S2 for further reaction. According to the method, hydrolysis vanadium precipitation and weak acid ammonium salt vanadium precipitation are combined, the product quality is improved through in-situ impurity removal, the problem that the content of impurity elements in a manganese-containing vanadium liquid vanadium precipitation product is high is solved, and the market competitiveness of a calcium method vanadium extraction process is improved.

Description

Technical Field

[0001] The invention relates to the technical field of vanadium hydrometallurgy, and in particular to a method for preparing vanadium oxide by utilizing manganese-containing acidic vanadium liquid. Background Art

[0002] As an important micro-alloying element, vanadium is widely used in metallurgy, chemical industry, aerospace and other fields. It can significantly improve the strength, toughness and ductility of steel, providing important support for ensuring the quality of key national projects.

[0003] In the process of vanadium extraction from vanadium slag calcium method, a part of manganese will combine with vanadium to form manganese vanadate salt. During acid leaching, vanadium and manganese will be leached into the solution at the same time to form manganese-containing acidic vanadium liquid. At the same time, a small amount of impurity elements such as magnesium, iron and silicon will also enter the manganese-containing acidic vanadium liquid. In industrial production, the acidic ammonium salt precipitation method is usually used to precipitate vanadium to prepare vanadium products. In this process, a small amount of impurity elements will enter the vanadium product, resulting in the problem of high impurity content in the product.

[0004] At present, the main vanadium precipitation process in the industrial vanadium extraction process is chemical precipitation, including hydrolysis precipitation, ammonium salt precipitation and iron salt precipitation. Hydrolysis precipitation is to add acid to the vanadium-containing solution to make the vanadate ions aggregate to form decavanadate ions, which are finally hydrolyzed to form H6V 10 O 28 Precipitation, i.e. hydration of vanadium pentoxide, is simple to operate, has low production cost, and allows vanadium concentration to fluctuate in a wide range. However, its disadvantage is that the purity of the product is low. The ammonium salt precipitation of vanadium is divided into acidic ammonium salt precipitation and weakly alkaline ammonium salt precipitation. Ammonium salt is added to vanadium liquid, and ammonium ions can combine with vanadium oxide ions to form poly(meta) ammonium vanadate precipitate. The acidic ammonium salt precipitation method has a high vanadium precipitation rate, but the types and contents of impurity elements in the product are relatively high. The types and contents of impurity elements in the product obtained by the weakly acidic ammonium salt precipitation method are relatively lower, but the vanadium precipitation rate is low. The iron salt precipitation process is to mix vanadium liquid with iron salt solution, heat and stir to precipitate vanadium to obtain a green solid product. The composition of the product is complex and the purity of the vanadium product is low.

[0005] Regarding the vanadium extraction technology of manganese-containing acidic vanadium liquid, a Chinese patent with application number CN117327929A discloses a method for ammonium-free vanadium precipitation in high manganese vanadium liquid, which comprises the following steps: passing chlorine dioxide into the acidic high manganese vanadium liquid for aeration, stirring the aerated solution, then filtering to remove the manganese dioxide precipitate, and taking the filtrate for standby use; adding a vanadium precipitator (a mixture of melamine and hexamethylenetetramine) to the filtrate for reaction, and then filtering to obtain a vanadium-rich precipitate; and calcining the obtained vanadium-rich precipitate to obtain a vanadium product.

[0006] Chinese patent application number CN107541599B discloses a preparation method for preparing high-purity vanadium using an acidic high-manganese vanadium-containing leaching solution, first removing impurity manganese under strong alkaline conditions, then precipitating and washing vanadium precipitates under strong acidic conditions, and finally calcining the vanadium precipitates to obtain the high-purity vanadium.

[0007] In the above method, the vanadium product obtained still contains a relatively high content of impurities and the separated solution cannot be recycled.

[0008] In view of this, the existing technology should be improved. Summary of the invention

[0009] The main purpose of the present invention is to provide a method for preparing vanadium oxide by using manganese-containing acidic vanadium liquid. First, low pH vanadium precipitation is used to separate vanadium from most impurity elements with low content, and vanadium and manganese are preliminarily separated to obtain a crude vanadium precipitate, which is then alkali-dissolved to separate vanadium and manganese in the precipitate to obtain a vanadium-containing solution with high purity, and then cooled and crystallized to obtain an ammonium metavanadate precipitate with high purity, and finally calcined to prepare a vanadium oxide product, and the upper liquid obtained by solid-liquid separation is returned for utilization, thereby maximizing economic benefits.

[0010] According to one aspect of the present invention, a method for preparing vanadium oxide using manganese-containing acidic vanadium liquid is provided, which comprises the following steps: S1, taking a manganese-containing acidic vanadium liquid and adjusting it to a preset pH value, stirring and reacting it under conditions T1 for t1, and obtaining a first vanadium precipitate after solid-liquid separation; S2, adding the first vanadium precipitate to an alkaline solution, heating to T2, stirring and reacting for t2, and obtaining a vanadium-containing solution and a manganese-containing waste slag after solid-liquid separation; S3, cooling the vanadium-containing solution to T3, slowly stirring the reaction for t3, and performing solid-liquid separation to obtain a second vanadium precipitate and an upper liquid; S4, oxidizing and calcining the second vanadium precipitate under conditions T4 to obtain a vanadium oxide product, adding alkaline solution to the upper liquid layer, and returning to step S2 for further reaction.

[0011] According to one embodiment of the present invention, the vanadium concentration in the manganese-containing acidic vanadium liquid is greater than 12 g / L, and the manganese concentration is greater than 3 g / L.

[0012] According to one embodiment of the present invention, the preset pH value ranges from 1.0 to 1.5.

[0013] According to one embodiment of the present invention, adjusting to a preset pH value includes adjusting by adding sulfuric acid and / or hydrochloric acid.

[0014] According to one embodiment of the present invention, the solid-liquid ratio of the first vanadium precipitate to the alkaline solution is 1:10-1:20 g / mL.

[0015] According to one embodiment of the present invention, the alkaline solution includes at least one of an ammonium bicarbonate solution and an ammonia solution.

[0016] According to one embodiment of the present invention, NH4 + Concentration>16g / L.

[0017] According to one embodiment of the present invention, in terms of mass percentage, the V2O5 content in the vanadium oxide product is greater than 99.5%, and the Mn content is less than 0.1%.

[0018] According to one embodiment of the present invention, after the alkaline solution is supplemented, the NH4 + Concentration>16g / L.

[0019] According to one embodiment of the present invention, T1 is 90-100° C., T2 is 65-80° C., T3 is 5-30° C., T4 is 500-600° C., t1 is 30-90 min, t2 is 20-60 min, and t3 is 30-90 min.

[0020] In a method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to an embodiment of the present invention, low pH vanadium precipitation is first used to separate vanadium from most impurity elements with low content, and vanadium and manganese are preliminarily separated to obtain a crude vanadium precipitate, which is then subjected to alkali dissolution to separate vanadium and manganese in the precipitate to obtain a vanadium-containing solution with high purity, which is then cooled and crystallized to obtain an ammonium metavanadate precipitate with high purity, which is finally calcined to prepare a vanadium oxide product, and the upper layer liquid obtained by solid-liquid separation is returned for utilization, thereby maximizing economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings required for use in the embodiment will be briefly introduced below. Obviously, the drawings described below are only some implementation cases of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A process flow chart of a method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to an exemplary embodiment of the present invention is shown. DETAILED DESCRIPTION

[0023] The detailed description of the following embodiments is used to exemplify the principles of the present invention, but cannot be used to limit the scope of the present invention. The present invention 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.

[0024] The present invention provides these embodiments to make this disclosure thorough and complete, and fully express the scope of the present invention to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of the parts and steps, the composition of materials, numerical expressions and numerical values ​​set forth in these embodiments should be interpreted as being merely exemplary, rather than as limiting.

[0025] It should be noted that, in the description of the present invention, unless otherwise specified, the meaning of "multiple" is greater than or equal to two; the terms "upper", "lower", "left", "right", "inner", "outer", etc., indicating the orientation or positional relationship, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0026] It should also be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. When a specific device is described as being located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device.

[0027] All terms used in the present invention have the same meanings as those understood by those of ordinary skill in the art to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries, for example, should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or extremely formal sense, unless explicitly defined herein.

[0028] Technologies, methods, and apparatus known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, these technologies, methods, and apparatus should be considered part of the specification.

[0029] like Figure 1 As shown, the present invention provides a method for preparing vanadium oxide using manganese-containing acidic vanadium liquid, which comprises the following steps: S1, taking a manganese-containing acidic vanadium liquid and adjusting it to a preset pH value, stirring and reacting it under conditions T1 for t1, and obtaining a first vanadium precipitate after solid-liquid separation; S2, adding the first vanadium precipitate to an alkaline solution, heating to T2, stirring and reacting for t2, and obtaining a vanadium-containing solution and a manganese-containing waste slag after solid-liquid separation; S3, cooling the vanadium-containing solution to T3, slowly stirring the reaction for t3, and performing solid-liquid separation to obtain a second vanadium precipitate and an upper liquid; S4, oxidizing and calcining the second vanadium precipitate under conditions T4 to obtain a vanadium oxide product, adding alkaline solution to the upper liquid layer, and returning to step S2 for further reaction.

[0030] In the method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to an embodiment of the present invention, low pH vanadium precipitation is first used to separate vanadium from most impurity elements with low content, and vanadium and manganese are preliminarily separated to obtain a crude vanadium precipitate, which is then subjected to alkali dissolution to separate vanadium and manganese in the precipitate to obtain a vanadium-containing solution with high purity, which is then cooled and crystallized to obtain a high-purity ammonium metavanadate precipitate, which is finally calcined to prepare a vanadium oxide product, and the upper liquid obtained by solid-liquid separation is returned for utilization, thereby maximizing economic benefits.

[0031] In some specific embodiments, the vanadium concentration in the manganese-containing acidic vanadium liquid is greater than 12 g / L, and the manganese concentration is greater than 3 g / L.

[0032] Based on the above embodiment, the preset pH value range is 1.0 to 1.5. The low pH vanadium precipitation method can achieve the separation of vanadium and most of the impurity elements with low content.

[0033] In some specific embodiments, adjusting to a preset pH value includes adjusting by adding sulfuric acid and / or hydrochloric acid. Adjusting the pH value by adding sulfuric acid and / or hydrochloric acid can inhibit the chemical reaction of some impurities. During the entire preparation process, there may be some impurities that react chemically with vanadium, affecting the purity and quality of the product. For example, some metal ions may form complex compounds with vanadium. By adjusting the pH value, these impurity ions can be kept in a state that is not easy to react with vanadium, or they can be precipitated and removed, thereby effectively preventing impurity interference and ensuring the high quality of vanadium oxide products.

[0034] Based on the above embodiment, the solid-liquid ratio of the first vanadium precipitate to the alkaline solution is 1:10-1:20 g / mL. The ratio of the mass of the vanadium precipitate to the volume of the alkaline solution is in the range of 1:10-1:20. The vanadium precipitate has sufficient space in the alkaline solution to react and dissolve. Since there is more alkaline solution, the vanadium precipitate can fully contact the alkaline solution.

[0035] In some specific embodiments, the alkaline solution includes at least one of an ammonium bicarbonate solution and an ammonia solution. The addition of ammonium bicarbonate and ammonia can play a role in adjusting and buffering the pH value. The ammonium bicarbonate solution is weakly alkaline, and ammonia is a base. The addition of them can increase the pH value of the solution to a range suitable for further separation of impurities and vanadium.

[0036] Based on the above examples, NH4 + Concentration>16g / L.

[0037] In some specific embodiments, in terms of mass percentage, the V2O5 content in the vanadium oxide product is greater than 99.5%, and the Mn content is less than 0.1%.

[0038] Based on the above examples, after the alkaline solution is added, the NH4 + Concentration>16g / L.

[0039] Based on the above embodiments, T1 is 90-100°C, T2 is 65-80°C, T3 is 5-30°C, T4 is 500-600°C, t1 is 30-90min, t2 is 20-60min, and t3 is 30-90min.

[0040] The present application is described below through specific embodiments.

[0041] Example 1 Take 200mL of manganese-containing acidic vanadium solution (V=24.58g / L, Mn=8.26g / L), add sulfuric acid to adjust the pH to 1.0, react at 95℃ for 60min, and separate the solid and liquid to obtain the first vanadium precipitate (containing 2.13% manganese); take the first vanadium precipitate and add it to ammonium bicarbonate and / or ammonia solution (containing NH4 + The solution was heated to 80°C and stirred for 30 minutes, and a vanadium-containing solution (containing 28.86 g / L vanadium) was obtained by solid-liquid separation. The vanadium-containing solution was cooled to 10°C and stirred for 60 minutes, and a second vanadium precipitate and an upper liquid (containing 1.68 g / L vanadium) were obtained by solid-liquid separation. The second vanadium precipitate was oxidized and calcined at 550°C to obtain vanadium pentoxide, the composition of which is shown in Table 1.

[0042] Example 2 Take 200mL of manganese-containing acidic vanadium solution (V=19.21g / L, Mn=6.65g / L), add hydrochloric acid to adjust the pH to 1.2, react at 90℃ for 90min, and separate the solid and liquid to obtain the first vanadium precipitate (containing 1.57% manganese); take the first vanadium precipitate and add it to ammonium bicarbonate and / or ammonia solution (containing NH4 + The solution was heated to 70°C and stirred for 20 minutes, and a vanadium-containing solution (containing 41.52 g / L vanadium) was obtained by solid-liquid separation. The vanadium-containing solution was cooled to 15°C and stirred for 60 minutes, and a second vanadium precipitate and an upper liquid (containing 2.28 g / L vanadium) were obtained by solid-liquid separation. The second vanadium precipitate was oxidized and calcined at 550°C to obtain vanadium pentoxide, the composition of which is shown in Table 1.

[0043] Example 3 Take 200mL of manganese-containing acidic vanadium liquid (V=14.82g / L, Mn=4.29g / L), add sulfuric acid to adjust the pH to 1.5, react at 100℃ (boiling) for 30min, and separate the solid and liquid to obtain the first vanadium precipitate (containing 0.64% manganese); take the first vanadium precipitate and add it to ammonium bicarbonate and / or ammonia solution (containing NH4 + The solution was heated to 75°C and stirred for 30 minutes, and a vanadium-containing solution (containing 23.75 g / L vanadium) was obtained by solid-liquid separation. The vanadium-containing solution was cooled to 20°C and stirred for 90 minutes, and a second vanadium precipitate and an upper liquid (containing 1.42 g / L vanadium) were obtained by solid-liquid separation. The second vanadium precipitate was oxidized and calcined at 550°C to obtain vanadium pentoxide, the composition of which is shown in Table 1.

[0044] Table 1 Vanadium pentoxide product composition / %

[0045] After the implementation of the present invention, at least the following beneficial effects are achieved: (1) The low pH vanadium precipitation method can separate vanadium from most impurity elements with low content. This method takes advantage of the differences in the precipitation properties of different elements under specific pH conditions, and preliminarily purifies vanadium in a targeted manner, reducing the impact of impurities on the quality of subsequent products. For example, under acidic conditions, many metal impurity ions may still exist in the solution in the form of ions, while vanadium can be precipitated preferentially, which lays a good foundation for the subsequent acquisition of high-quality vanadium oxide, so that the purity of the final product can be effectively guaranteed.

[0046] (2) This method further separates vanadium and manganese from the precipitate through a subsequent alkaline dissolution step. Manganese is a key element in manganese-containing acidic vanadium liquid, and its effective separation is crucial to improving the quality of vanadium oxide. Through these two separation steps, the manganese content in the product can be significantly reduced, and the purity of the vanadium oxide product can be improved, making it more in line with the requirements of high-quality products.

[0047] (3) After a series of separation and crystallization processes, a high-purity ammonium metavanadate precipitate is finally obtained. Starting from the manganese-containing acidic vanadium liquid, the purity of the ammonium metavanadate precipitate is improved by gradually removing impurities and separating other metal elements, such as through the fine operation of vanadium precipitation, alkali dissolution and cooling crystallization. This high-purity ammonium metavanadate precipitate provides high-quality raw materials for the subsequent calcination to prepare high-quality vanadium oxide products, so that the final vanadium oxide product can reach a higher standard in terms of purity and meet the strict requirements of the application field for the quality of vanadium oxide.

[0048] (4) The entire preparation method has clear steps, including vanadium precipitation, alkali dissolution, cooling crystallization and calcination. The quality of the product can be guaranteed by controlling process parameters (such as pH value, temperature, crystallization time, etc.). This clear process route makes the product quality stable and controllable, which is conducive to the large-scale and high-quality production of vanadium oxide products, reduces the fluctuation of product quality, and provides reliable technical support for the industrial production of high-quality vanadium oxide.

[0049] The above are exemplary embodiments disclosed in the present invention. The order disclosed in the above embodiments of the present invention is for description only and does not represent the advantages and disadvantages of the embodiments. However, it should be noted that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope disclosed in the embodiments of the present invention (including the claims) is limited to these examples. Various changes and modifications may be made without departing from the scope defined in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.

[0050] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A method for preparing vanadium oxide using manganese-containing acidic vanadium liquid, characterized in that: The following steps are involved: S1, taking a manganese-containing acidic vanadium liquid and adjusting it to a preset pH value, stirring and reacting it under conditions T1 for t1, and obtaining a first vanadium precipitate after solid-liquid separation; S2, adding the first vanadium precipitate to an alkaline solution, heating to T2, stirring and reacting for t2, and obtaining a vanadium-containing solution and a manganese-containing waste slag after solid-liquid separation; S3, cooling the vanadium-containing solution to T3, slowly stirring the reaction for t3, and performing solid-liquid separation to obtain a second vanadium precipitate and an upper liquid; S4, oxidizing and calcining the second vanadium precipitate under conditions T4 to obtain a vanadium oxide product, adding the alkaline solution to the upper liquid, and returning to step S2 for further reaction.

2. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 1, characterized in that: The vanadium concentration in the manganese-containing acidic vanadium liquid is greater than 12 g / L, and the manganese concentration is greater than 3 g / L.

3. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 1, characterized in that: The preset pH value ranges from 1.0 to 1.

5.

4. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 1, characterized in that: The adjusting to the preset pH value includes adjusting by adding sulfuric acid and / or hydrochloric acid.

5. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 1, characterized in that: The solid-to-liquid ratio of the first vanadium precipitate to the alkaline solution is 1:10-1:20 g / mL.

6. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 1, characterized in that: The alkaline solution includes at least one of an ammonium bicarbonate solution and an ammonia solution.

7. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 6, characterized in that: NH4 in the ammonium bicarbonate solution and the ammonia solution + Concentration>16g / L.

8. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 1, characterized in that: In terms of mass percentage, the V2O5 content in the vanadium oxide product is greater than 99.5%, and the Mn content is less than 0.1%.

9. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 7, characterized in that: After the alkaline solution is added, the NH4 + Concentration>16g / L.

10. The method for preparing vanadium oxide using manganese-containing acidic vanadium liquid according to claim 1, characterized in that: The T1 is 90-100°C, the T2 is 65-80°C, the T3 is 5-30°C, the T4 is 500-600°C, the t1 is 30-90min, the t2 is 20-60min, and the t3 is 30-90min.

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