A method for preparing 5n ammonium rhenate

Abstract

The present application relates to the field of metallurgical materials, and particularly relates to a purification method of ammonium rhenate. The method specifically comprises the following steps: taking impure ammonium rhenate as raw material, adding the raw material and ultrapure water into a reaction container, obtaining an ammonium rhenate solution with a certain concentration after complete dissolution, and reserving; the dissolved ammonium rhenate solution is subjected to adsorption and impurity removal through an adsorption tube filled with attapulgite, the ammonium rhenate after adsorption and impurity removal is precisely filtered, then the ammonium rhenate filtrate is subjected to freeze centrifugal crystallization to obtain mixed slurry; the mixed slurry is filtered to obtain pre-crystallization powder and ammonium rhenate refined filtrate; the obtained ammonium rhenate refined filtrate is subjected to low-temperature slow recrystallization again, the recrystallization slurry is filtered, and 5N ammonium rhenate is obtained after the recrystallization is washed with ultrapure water and freeze-dried, and the remaining ammonium rhenate filtrate is evaporated and concentrated to a certain concentration, then subjected to adsorption and impurity removal again, and reused.

Description

Technical Field

[0001] This invention relates to the field of metallurgical materials, and in particular to a method for preparing 5N ammonium perrylate. Background Technology

[0002] Rhenium is a rare dispersed metal. At high temperatures, rhenium and rhenium alloys exhibit excellent resistance to thermal shock and creep, a phenomenon known as the "rhenium effect." Generally, 4N purity rhenium products meet the requirements, while certain aerospace-grade rhenium products have higher purity requirements. In the mainstream hydrogen reduction process for preparing high-purity rhenium powder, high-purity ammonium perrhenate is required. Therefore, as a raw material for preparing 5N rhenium powder, ammonium perrhenate with a higher purity than 2N or 4N is required, and the content of various impurities must meet specific requirements to produce a qualified high-purity rhenium product. Therefore, the purification of ammonium perrhenate is of great significance for the preparation of high-purity rhenium products.

[0003] Recrystallization is currently the most mature process for purifying high-purity ammonium perrylate, especially for ammonium perrylate raw materials with low impurity content. Recrystallization can remove specific impurities. Its principle is based on the difference in solubility of the substance to be purified and the impurities in the solvent. While the substance to be purified precipitates from the supersaturated solution, all or most of the impurities remain in the solution. If the impurities have extremely low solubility in the solvent, they are removed by filtration after preparing a saturated solution, thus achieving purification. Macroscopically, it involves the redistribution of highly soluble impurities in the raw material between the solution and the crystals, while less soluble impurities are filtered out. Microscopically, during crystallization, the substance to be purified crystallizes out in an orderly manner.

[0004] The process for purifying 5N ammonium peroxide, as described in patent CN 110527854 B, is complex and involves numerous steps. Therefore, how to prepare 5N ammonium peroxide through a simple process control is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] This invention discloses a method for preparing 5N ammonium perrylate to solve any of the above-mentioned and other potential problems in the prior art.

[0006] To achieve the above objectives, the technical solution of the present invention is: a method for preparing 5N ammonium perrylate, the method specifically including the following steps:

[0007] S1) Using ammonium peroxide containing rhenium as raw material, the raw material is mixed with ultrapure water, heated to a certain temperature, and kept at that temperature for a period of time to obtain an ammonium peroxide solution of a certain concentration for later use;

[0008] S2) The ammonium perrye solution obtained in S1) is passed through an adsorption tube filled with attapulgite for adsorption and impurity removal. After adsorption and impurity removal, it is then filtered through a precision filter to obtain ammonium perrye filtrate.

[0009] S3) Place the ammonium perrylate filtrate from S2) into a refrigerated centrifuge, set a certain temperature and centrifugation rate, and obtain a centrifuged crystallized mixed slurry after the refrigerated centrifugation is completed;

[0010] S4) The mixed slurry containing centrifugal crystals in S3) is filtered to obtain pre-crystallized powder and ammonium peroxide purified filtrate. The ammonium peroxide purified filtrate is then subjected to low-temperature slow recrystallization again.

[0011] S5) The recrystallized slurry obtained in S4) is filtered, washed with ultrapure water, recrystallized, and freeze-dried to obtain 5N ammonium rhenium. The filtrate is then concentrated by evaporation and returned to attapulgite for adsorption and impurity removal.

[0012] Furthermore, the purity of the ammonium perrylate raw material in S1) is 2N-4N:

[0013] The reaction temperature is 40-80℃, and the holding time is 1-4h; the concentration of the ammonium perrylate solution is 30g / L-60g / L.

[0014] Furthermore, the adsorption and impurity removal parameters in S2) are:

[0015] The adsorption and impurity removal temperature of the adsorption tube filled with attapulgite is controlled at 30℃-50℃, and the volume ratio of solution to attapulgite is controlled at 20 / 1-50 / 1.

[0016] Furthermore, in S2), the precision filtration control precision filtration pore size is 0.5-10 micrometers.

[0017] Furthermore, the freezing centrifugation parameters in S3) are:

[0018] Control the refrigerated centrifugation temperature to 5℃-10℃, the refrigerated centrifugation speed to 2000-6000 r / min, and the refrigerated centrifugation time to 30s-180s.

[0019] Furthermore, in S4), the low-temperature slow recrystallization temperature is -5℃ to 5℃, and the low-temperature slow recrystallization temperature is 12h to 24h.

[0020] Furthermore, the recrystallization freeze-drying pressure in S5) is 10-300 Pa, the drying temperature is -10℃ to 0℃, and the drying time is 8h-12h.

[0021] Furthermore, the container used for drying ammonium perrylate in S5) is a high-purity quartz disc.

[0022] Furthermore, the filtrate in step S5) is evaporated and concentrated to a concentration of 30 g / L-60 g / L before being returned to adsorption for impurity removal.

[0023] A 5N ammonium perrylate, which is prepared by the method described above.

[0024] The beneficial effects of this invention are as follows: Due to the adoption of the above technical solution, the method of this invention has the advantages of simple process control in preparing 5N ammonium rhenium. Most of the heavy metals, alkali metals and alkaline earth metals in the raw materials can be removed by adsorption and two-stage crystallization, forming an effective open circuit for impurities. It can stably purify the raw materials from 3N-4N to 5N level, avoid the complicated steps of multiple recrystallization, consume less energy, have less rhenium loss and high yield. Attached Figure Description

[0025] Figure 1 This is a schematic flowchart of a method for preparing 5N ammonium perrylate according to the present invention.

[0026] Figure 2 This is a third-party GDMS test report of the 5N ammonium perrylate prepared in this invention. Detailed Implementation

[0027] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0028] like Figure 1 As shown, the present invention provides a method for preparing 5N ammonium perrylate, which specifically includes the following steps:

[0029] S1) Using ammonium peroxide containing rhenium as raw material, the raw material is mixed with ultrapure water, heated to a certain temperature, and kept at that temperature for a period of time to obtain an ammonium peroxide solution of a certain concentration for later use;

[0030] S2) The ammonium perrye solution obtained in S1) is passed through an adsorption tube filled with attapulgite for adsorption and impurity removal. After adsorption and impurity removal, it is then filtered through a precision filter to obtain ammonium perrye filtrate.

[0031] S3) Place the ammonium perrylate filtrate from S2) into a refrigerated centrifuge, set a certain temperature and centrifugation rate, and obtain a centrifuged crystallized mixed slurry after the refrigerated centrifugation is completed;

[0032] S4) The mixed slurry containing centrifugal crystals in S3) is filtered to obtain pre-crystallized powder and ammonium peroxide purified filtrate. The ammonium peroxide purified filtrate is then subjected to low-temperature slow recrystallization again.

[0033] S5) The recrystallized slurry obtained in S4) is filtered, washed with ultrapure water, recrystallized, and freeze-dried to obtain 5N ammonium rhenium. The filtrate is then concentrated by evaporation and returned to attapulgite for adsorption and impurity removal.

[0034] The purity of the ammonium perrylate raw material in S1) is 2N-4N.

[0035] The reaction temperature is 40-80℃, and the holding time is 1-4h. The concentration of the ammonium perrylate solution is 30g / L-60g / L. A certain concentration of ammonium perrylate solution is fully dissolved to avoid the precipitation of ammonium perrylate crystals during attapulgite adsorption, thus ensuring the adsorption effect of attapulgite.

[0036] The adsorption and impurity removal parameters in S2) are:

[0037] The adsorption temperature of the adsorption tube filled with attapulgite is controlled at 30℃-50℃, and the volume ratio of solution to attapulgite is controlled at 20 / 1-50 / 1. Most of the heavy metal ions and some alkali metal and alkaline earth metal impurities are removed during the adsorption process of attapulgite.

[0038] In S2), the precision filtration control has a pore size of 0.5-10 micrometers. Precision filtration avoids the introduction of new impurities by allowing fine attapulgite fragments to enter the filtrate after impurity removal.

[0039] The freezing centrifugation parameters in S3) are:

[0040] The freezing centrifugation temperature was controlled at 5℃-10℃, the freezing centrifugation speed at 2000-6000 r / min, and the freezing centrifugation time at 30s-180s. The crystals obtained by freezing centrifugation contained most of the alkali metal and alkaline earth metal impurities. After filtering the impurity-containing pre-crystallization, a higher purity ammonium rhenium acid solution was obtained.

[0041] The low-temperature slow recrystallization temperature in S4 is -5℃ to 5℃, and the low-temperature slow recrystallization temperature is 12h to 24h.

[0042] The recrystallization freeze-drying pressure in S5) is 10-300 Pa, the drying temperature is -10℃ to 0℃, and the drying time is 8h-12h. Sealed freeze-drying avoids the introduction of air impurities during the drying process.

[0043] The container used for drying ammonium perrylate in S5) is a high-purity quartz disc.

[0044] The filtrate in S5) is evaporated and concentrated to a concentration of 30g / L-60g / L before being returned to adsorption for impurity removal.

[0045] Example 1:

[0046] First, 400g of 2N ammonium perrylate was dissolved in ultrapure water at a concentration of 30g / L in a glass container and heated to 50℃. After the solution became clear, the temperature was maintained and the mixture was stirred for 2 hours. The clarified ammonium perrylate solution was then passed through an adsorption tube at 40℃ with a solution volume to attapulgite volume ratio of 20. After adsorption and impurity removal, the solution was further filtered through a 2-micron pore size filter. The filtered liquid was then placed in a refrigerated centrifuge at 10℃, a speed of 5000 r / min, and a centrifugation time of 60s. After centrifugation, the mixed slurry was filtered, and the resulting ammonium perrylate filtrate was slowly recrystallized at 0℃ for 12 hours. The recrystallized slurry was filtered, washed with ultrapure water, and then freeze-dried and recrystallized for 12 hours at 50Pa pressure and -5℃ using a high-purity quartz disc as a container, finally yielding 147g of 5N ammonium perrylate. The remaining ammonium perrylate filtrate was evaporated and concentrated, and then used as return material for further adsorption and impurity removal. The test data for 5N ammonium perrylate are shown in Table 1.

[0047] Table 1. Test data for 5N ammonium perrylate

[0048]

[0049] Example 2:

[0050] First, 320g of 3N ammonium perrylate was dissolved in ultrapure water at a concentration of 50g / L in a glass container and heated to 60℃. After the solution became clear, the temperature was maintained and the mixture was stirred for 2 hours. The clarified ammonium perrylate solution was then passed through an adsorption tube at 40℃ with a solution volume to attapulgite volume ratio of 30. After adsorption and impurity removal, the solution was then finely filtered through a 1-micron filter. The filtered liquid was placed in a refrigerated centrifuge at 5℃, a speed of 6000 r / min, and a centrifugation time of 60s. After centrifugation, the mixed slurry was filtered, and the resulting ammonium perrylate filtrate was slowly recrystallized at 0℃ for 18 hours. The recrystallized slurry was filtered, washed with ultrapure water, and then freeze-dried and recrystallized for 12 hours at 100Pa pressure and -5℃ using a high-purity quartz disc as a container, finally yielding 176g of 5N ammonium perrylate. The remaining ammonium perrylate filtrate was evaporated and concentrated, and then used as return material for further adsorption and impurity removal. The test data for 5N ammonium perrylate are shown in Table 2.

[0051] Table 2 Test data for 5N ammonium perrylate

[0052]

[0053] Example 3:

[0054] First, 500g of 4N ammonium perrylate was dissolved in ultrapure water at a concentration of 60g / L in a glass container and heated to 80℃. After the solution became clear, the temperature was maintained and the mixture was stirred for 2 hours. The clarified ammonium perrylate solution was then passed through an adsorption tube at 50℃ with a solution volume to attapulgite volume ratio of 50. After adsorption and impurity removal, the solution was further filtered through a 0.5-micron filter. The filtered liquid was then placed in a refrigerated centrifuge at 0℃, a speed of 4000 r / min, and a centrifugation time of 60s. After centrifugation, the mixed slurry was filtered, and the resulting ammonium perrylate filtrate was slowly recrystallized at -5℃ for 24 hours. The recrystallized slurry was filtered, washed with ultrapure water, and then freeze-dried and recrystallized for 12 hours at 50Pa pressure and -5℃ using a high-purity quartz disc as a container, finally yielding 294g of 5N ammonium perrylate. The remaining ammonium perrylate filtrate was evaporated and concentrated, and then used as return material for further adsorption and impurity removal. The test data for 5N ammonium perrylate are shown in Table 3.

[0055] Table 3. Test data for 5N ammonium perrylate

[0056]

[0057] The above provides a detailed description of a method for preparing 5N ammonium perrylate according to the embodiments of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and its core ideas; furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

[0058] Certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The terms "comprising" and "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising / including but not limited to". "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error. The following descriptions in the specification are preferred embodiments for carrying out this application; however, these descriptions are for the purpose of illustrating the general principles of this application and are not intended to limit the scope of this application. The scope of protection of this application shall be determined by the appended claims.

[0059] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes said element.

[0060] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0061] The foregoing description illustrates and describes several preferred embodiments of this application. However, as previously stated, it should be understood that this application is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the application concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of this application should be within the protection scope of the appended claims.

Claims

1. A method for preparing 5N ammonium perrylate, characterized in that, The method specifically includes the following steps: S1) Using ammonium peroxide containing rhenium as raw material, the raw material is mixed with ultrapure water, heated to a certain temperature, and kept at that temperature for a period of time to obtain an ammonium peroxide solution of a certain concentration for later use; The purity of the ammonium peroxide containing rhenium is 2N-4N, the reaction temperature is 40-80℃, and the holding time is 1-4h; the concentration of the ammonium peroxide solution is 30g / L-60g / L. S2) The ammonium perrye solution obtained in S1) is passed through an adsorption tube filled with attapulgite for adsorption and impurity removal. After adsorption and impurity removal, it is then subjected to precision filtration to obtain ammonium perrye filtrate. The adsorption temperature of the adsorption tube filled with attapulgite is controlled at 30℃-50℃, and the volume ratio of solution to attapulgite is controlled at 20 / 1-50 / 1; the pore size of the precision filter is controlled at 0.5-10 micrometers. S3) The ammonium perrye filtrate obtained in S2) is placed in a refrigerated centrifuge. After setting a certain temperature and centrifugation rate, the centrifuged crystallized mixed slurry is obtained after the refrigerated centrifugation is completed. S4) The mixed slurry containing centrifugal crystals obtained in S3) is filtered to obtain pre-crystallized powder and ammonium peroxide purified filtrate. The ammonium peroxide purified filtrate is then subjected to low-temperature slow recrystallization again. S5) The recrystallized slurry obtained in S4) is filtered, washed with ultrapure water, recrystallized, and freeze-dried to obtain 5N ammonium rhenium. The filtrate is then concentrated by evaporation and returned to attapulgite for adsorption and impurity removal.

2. The method according to claim 1, characterized in that, In S3): Control the refrigerated centrifugation temperature to 5℃-10℃, the refrigerated centrifugation speed to 2000-6000 r / min, and the refrigerated centrifugation time to 30s-180s.

3. The method according to claim 1, characterized in that, The low-temperature slow recrystallization temperature in S4 is -5℃ to 5℃, and the low-temperature recrystallization time is 12h to 24h.

4. The method according to claim 1, characterized in that, The recrystallization freeze-drying pressure in S5) is 10-300 Pa, the drying temperature is -10℃ to 0℃, the drying time is 8h-12h, and the container used for drying ammonium perrylate is a high-purity quartz disc.

5. The method according to claim 1, characterized in that, The filtrate in S5) is evaporated and concentrated to a concentration of 30g / L-60g / L before being returned to attapulgite for adsorption and impurity removal.

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