A method for preparing high-purity ammonium perrylate from complex rhenium-containing solutions

Abstract

This invention discloses a method for preparing high-purity ammonium perrylate from complex rhenium-containing solutions. The specific steps are as follows: rhenium can be selectively extracted from the complex solution using an extractant; rhenium is back-extracted from the organic phase using ammonia; the back-extraction solution is concentrated to remove most of the entrained organic phase, increasing the crystallinity of rhenium; centrifugation and dehydration are then performed to generate crude crystals; hot water is added to dissolve the crude crystals, followed by the addition of a displacement agent to remove impurities such as lead and copper; hydrogen peroxide and ammonia are added to remove impurities such as silicon and the organic phase adsorbed by the crystals, resulting in a purified solution; the purified solution undergoes secondary crystallization, followed by the addition of hydrogen peroxide and ammonia to dissolve the secondary crude crystals for further deep purification; the purified solution is then crystallized again, centrifuged, dehydrated, and dried to obtain 4N ammonium perrylate. This invention uses displacement, potential control, pH purification, and multi-stage crystallization to prepare high-purity ammonium perrylate. The entire process is simple and controllable, with a high rhenium recovery rate, enabling the effective recovery of rare metals.

Description

Technical Field

[0001] This invention belongs to the field of non-ferrous metal smelting technology, and particularly relates to a method for preparing high-purity ammonium perrylate from complex rhenium-containing solutions. Background Technology

[0002] Rhenium is a rare and dispersed metal, primarily found in molybdenite and bornite. Copper concentrate, used as a raw material in copper smelting, typically contains 3-50 g / t of rhenium. Under the high-temperature conditions of pyrometallurgical processes, the rhenium in the copper concentrate oxidizes to gaseous Re₂O₇, which enters the flue gas purification system. After washing with dilute acid, it is converted to ReO₄⁻. - The arsenic is introduced into copper smelting waste liquid and undergoes a sulfidation process to form a rhenium-arsenic filter cake. This filter cake, as a primary resource of rhenium, is characterized by high arsenic content and low rhenium content. A redox process can achieve partial separation of arsenic and rhenium, yielding a solution containing rhenium and arsenic.

[0003] Currently, chemical precipitation, ion exchange, and solvent extraction are the main separation methods for enriching rhenium from rhenium-containing solutions. Chemical precipitation utilizes the difference in solubility of rhenium with other coexisting ions in solution to achieve selective precipitation of rhenium. Although chemical precipitation is simple and convenient to operate, it consumes a large amount of chemical reagents and produces a large amount of waste residue that is difficult to treat effectively. Ion exchange utilizes ion exchange resins to exchange ions with Re(VII) to achieve adsorption and separation of Re(VII) from solution. Ion exchange has the advantages of good selectivity and high separation efficiency, but it also has disadvantages such as expensive resins, difficult regeneration, and difficult disposal of waste resin. Solvent extraction uses an organic solvent as the extractant to extract Re(VII) from the solution into the organic solution, and then uses a back-extraction agent to back-extract the Re(VII) from the organic solvent, thereby achieving the separation and recovery of Re(VII) from the solution. Solvent extraction has advantages such as high extraction and separation efficiency of Re(VII), simple process, and low cost, and is therefore widely used in industry. However, high-purity ammonium rheniumate cannot be obtained by extraction alone. Therefore, other processes must be combined with extraction processes to deeply purify ammonium perrylate solution and prepare high-purity ammonium perrylate.

[0004] Existing technologies disclose a method for crystallizing ammonium peroxide solution. This method is simple to operate, but the grade of the obtained ammonium peroxide is low. Other methods involve treating smelting waste acid through pretreatment, centrifugal extraction, and recrystallization. However, these methods lack process control and have few optimized parameters, resulting in ammonium peroxide with a grade of only 3N. Alternatively, high-purity ammonium peroxide can be prepared through multi-stage cooling, controlling the cooling temperature and time. However, this method requires crude ammonium peroxide solution as raw material, placing high demands on the raw material. Furthermore, the prepared ammonium peroxide is mostly 3N, requiring multiple optimization processes to obtain 4N peroxide. Summary of the Invention

[0005] This invention discloses a method for preparing high-purity ammonium rhenium from complex rhenium-containing solutions, in order to solve any of the above-mentioned and other potential problems of the prior art.

[0006] To achieve the above objectives, the technical solution of the present invention is: a method for preparing high-purity ammonium rheniumate from a complex rhenium-containing solution, the method specifically including the following steps:

[0007] S1) Extraction and back-extraction: A complex rhenium-containing solution is mixed with an organic phase according to a certain extraction ratio. The rhenium-containing organic phase is separated and transferred to the back-extraction process. After the third phase is removed, a back-extraction agent is added to perform separation and back-extraction to obtain the back-extraction solution.

[0008] S2) Concentration: The back-extraction solution obtained in S1) is heated and concentrated until the reaction endpoint is reached. After adding a certain amount of ammonia, it is filtered to obtain the concentrated solution.

[0009] S3) Primary crystallization: After freezing the concentrated solution obtained in S2) for a certain period of time, primary crude crystals and primary crystallization residue are obtained; the primary crystallization residue can be concentrated together with the back-extraction solution in S2) during the next reaction;

[0010] S4) First dissolution and impurity removal: Add a certain amount of hot water to the crude crystals obtained in S3) and stir until completely dissolved. Then add a displacement agent to remove impurities for a certain period of time. Add hydrogen peroxide and ammonia water until the endpoint potential and endpoint pH are reached. Filter to obtain the liquid after first impurity removal.

[0011] S5) Secondary crystallization: After freezing the liquid obtained from the first purification in S4) for a certain period of time, a secondary crude crystal and a secondary crystallization residue are obtained; the secondary crystallization residue can be concentrated together with the back-extraction liquid in S2) during the next reaction;

[0012] S6) Secondary dissolution and impurity removal: Add a certain amount of hot water to the secondary crude crystals obtained in S5) and stir until completely dissolved. Then add hydrogen peroxide and ammonia water to the endpoint potential and endpoint pH to remove impurities from the secondary crude crystals. Filter to obtain the liquid after secondary impurity removal.

[0013] S7) Three-stage crystallization; the liquid obtained after secondary impurity removal from S6) is placed in a freezer, frozen for a certain period of time, and then filtered. The obtained three-stage crystals are centrifuged, dehydrated, and dried to obtain high-purity ammonium rhenium.

[0014] Furthermore, compared to extraction with an organic phase, the complex rhenium-containing solution in S1) has the following advantages: V 有机相 V 液 =1:5~20, with 4~8 extraction stages;

[0015] The extraction process uses N as the organic extractant. 235 2-Octanol: Kerosene (V N235 V仲辛醇 V 煤油 A mixture of 20:20:60, wherein the back-extraction agent in the back-extraction process is ammonia, and the extraction ratio (V) 有机相 V 液 =1:0.5~10, with 4~8 stages of back-extraction.

[0016] Furthermore, the concentration process in S2) is as follows: the concentration temperature is 70-100℃, the concentration endpoint specific gravity is 1.15-1.20, the amount of ammonia added is 1 / 30 to 1 / 60 of the volume of the back-extraction liquid, and the ammonia concentration is 10-20wt%.

[0017] Furthermore, the primary crystallization process in S3) is as follows: the freezing crystallization temperature is -20~-10℃, and the freezing time is 12~20 h.

[0018] Furthermore, the specific process of the first dissolution and impurity removal in S4) is as follows: hot water is added to dissolve the first crystal, the solid-liquid ratio (m solid:m liquid) is 1:2~8; the amount of displacement agent added is 5~80 g / L, and after reacting for 0.5~1.5h, hydrogen peroxide and ammonia are added in sequence to remove impurities.

[0019] Among them, hydrogen peroxide was added to control the endpoint potential to 400-640 mV, and ammonia was added to control the endpoint pH to 8-10.

[0020] The displacing agent is one or more of iron powder, zinc powder, and aluminum powder.

[0021] Furthermore, the specific process of secondary crystallization in S5 is as follows: the freezing crystallization temperature is -20~-10℃, and the freezing time is 12~20 h.

[0022] Furthermore, the specific process for the secondary dissolution and impurity removal in S6) is as follows: hot water, hydrogen peroxide, and ammonia are added sequentially to dissolve the secondary coarse crystals, with a solid-liquid ratio (m... 固 :m 液 The ratio is 1:2~8; where hydrogen peroxide is added to control the endpoint potential at 640-1300 mV, and ammonia is added to control the endpoint pH at 8-10.

[0023] Furthermore, the freezing temperature for the three-stage crystallization in S7 is -20 to -10°C, and the freezing time is 12 to 20 hours.

[0024] Furthermore, the purity of the high-purity ammonium perrylate is above 99.99%, and the rhenium recovery rate in the rhenium-containing solution reaches above 95%.

[0025] A 4N ammonium perrylate, wherein the 4N ammonium perrylate is prepared by the above method.

[0026] The advantages of this invention are as follows: Due to the adoption of the above technical solution, the entire preparation method of this invention is controllable, easy to operate, and has a high recovery rate of valuable metals, recovering more than 95% of the rhenium in the rhenium-containing solution; the process is highly adaptable and can prepare high-purity ammonium rheniumate from various complex rhenium-containing solutions; the process employs iron powder replacement, potential and pH control for impurity removal, and multi-stage crystallization, effectively removing impurities such as lead, copper, silicon, arsenic, and iron to achieve the preparation of 4N ammonium rheniumate; the process does not generate new wastewater, has no secondary pollution, is environmentally friendly, safe, and environmentally friendly; the reagents used in this method are inexpensive, the equipment is simple and requires little space, the operation is simple, and it is easy to industrialize, thus possessing significant economic and social benefits. Attached Figure Description

[0027] Figure 1 This is a process flow diagram of a method for preparing high-purity ammonium perrylate from a complex rhenium-containing solution according to the present invention.

[0028] Figure 2 This is a process flow diagram of Example 1 using the method of the present invention. Detailed Implementation

[0029] The following description, as an example of the preparation of high-purity ammonium rhenium according to the present invention, illustrates the process of obtaining high-purity ammonium rhenium via a complex rhenium-containing solution. Obviously, the described embodiments are merely some, not all, embodiments of the present invention. All equivalent variations and modifications made within the scope of the present invention should still fall within the patent coverage of the present invention.

[0030] This invention uses complex rhenium-containing solutions, such as high-lead smelting waste acid or copper smelting waste acid, as raw materials. The waste acid is enriched in sulfide slag through sulfidation, and then the complex rhenium-containing solution is obtained through leaching from the sulfide slag. High-purity ammonium rheniumate is prepared through organic phase extraction, ammonia back-extraction, primary crystallization, primary dissolution, primary displacement purification, secondary crystallization, secondary dissolution, secondary purification, and tertiary crystallization. Figure 1 As shown.

[0031] Rhenium can be selectively extracted in complex solutions using an extractant, and back-extracted from the organic phase using ammonia. Concentrating the back-extraction solution removes most of the entrained organic phase, increasing the crystallinity of rhenium. The concentrated solution is then centrifuged to dehydrate and generate crude crystals. Hot water is added to dissolve the crude crystals, and a certain amount of displacement agent is added to remove impurities such as lead and copper. Hydrogen peroxide and ammonia are added to remove impurities such as Si and the organic phase adsorbed on the crystals, resulting in a purified solution. After secondary crystallization, hydrogen peroxide and ammonia are added to dissolve the secondary crude crystals for a second deep purification. The purified solution is then crystallized again, centrifuged to dehydrate, and dried to obtain 4N ammonium rheniumate.

[0032] Specifically, this invention provides a method for preparing high-purity ammonium rheniumate from complex rhenium-containing solutions, wherein the complex rhenium-containing solution is prepared by extraction with a ratio (V) 有机相 V 液 Add N under the condition that the ratio is 1:5~20 235 2-Octanol: Kerosene (V N235 V 仲辛醇 V 煤油 A mixture of 20:20:60 (rhenium, argon, and sulfur) is used to ensure sufficient contact between the organic phase and the complex rhenium-containing solution. This is achieved through various known methods, including but not limited to stirring or shaking. Typically, the extraction time is 10-60 minutes. The extraction temperature is 20-40°C; excessively high temperatures may cause the organic phase to volatilize. The extraction stages are 4-8. The following reactions typically occur during the extraction process:

[0033] R3N + H2SO4 = R3NH·HSO4

[0034] R3NH·HSO4+HReO4= R3NH·ReO4+ H2SO4,

[0035] Generally, extraction can separate most impurities such as magnesium, copper, and zinc. After the extraction reaction, the organic phase is washed with pure water to eliminate the third phase. The organic phase is then transferred to the back-extraction process, where it undergoes further back-extraction with ammonia water, resulting in the following reaction:

[0036] R3NH·ReO4+NH3·H2O=R3N+NH4ReO4+H2O

[0037] Thus, rhenium is enriched in the aqueous solution through ammonia back-extraction. The preferred ammonia concentration is 20-24 wt%, the preferred back-extraction temperature is 20-40°C, the preferred back-extraction time is 10-60 min, and the preferred number of back-extraction stages is 4. To ensure the back-extraction reaction proceeds fully, various known methods, including but not limited to stirring or shaking, are employed. The back-extracted liquid is then transferred to a concentration process.

[0038] To improve the crystallization rate, the stripping solution needs to be concentrated. The concentration is determined by controlling the change in the solution's specific gravity, with the preferred specific gravity at the reaction endpoint being 1.15–1.20, and the preferred concentration temperature being 70–100°C. After concentration, a certain amount of ammonia is added, followed by filtration to obtain the concentrated solution. The preferred amount of ammonia added is 1 / 30 to 1 / 60 of the stripping solution volume, and the ammonia concentration is 10–20 wt%.

[0039] The concentrated solution undergoes a first freeze crystallization. There are no particular limitations; the crystallization reaction can be carried out using various known equipment and methods, such as a freeze crystallizer or plate / tube heat exchangers. The freeze crystallization temperature is preferably -20 to -10°C, more preferably -18 to -12°C, and the freeze crystallization time is preferably 10 to 20 hours. After filtration, the primary coarse crystal is transferred to a primary impurity removal process, and the primary crystallization residue is returned to the concentration process. The primary coarse crystal is then treated with hot water to form a primary solution.

[0040] Generally, some metals, especially lead and iron, are back-extracted into the organic phase along with rhenium. The Chinese nonferrous metals industry standard for ammonium permanganate (YS / T984 2013) requires that the content of Pb and K not exceed 40 ppm, the content of Ca, Fe, W, and Na not exceed 20 ppm, and the content of Mo, Cu, Mg, and Ni not exceed 10 ppm. This shows that this type of ammonium permanganate has the lowest requirement for divalent ions (Pb), while lead is the most difficult divalent metal ion to remove. Typically, lead removal is achieved through resin adsorption, which is expensive and carries risks of resin poisoning and the difficult treatment of waste resin containing inorganic substances. To remove impurities such as copper, antimony, and lead that accompany rhenium extraction and back-extraction, one or more of iron powder, zinc powder, and aluminum powder are used to deeply remove impurities from the primary crystallization solution. The reaction is as follows:

[0041] Pb 2+ +Fe=Fe 2+ +Pb,

[0042] Pb 2+ Zn= Zn 2+ +Pb,

[0043] Cu 2+ +Fe=Fe 2+ +Cu,

[0044] Cu 2+ +Zn= Zn 2+ +Cu,

[0045] 2Al + 3Cu 2+ ═2Al 3+ +3Cu,

[0046] To achieve deep impurity removal, the preferred mesh size of the displacement agent is 100-3000 mesh, the preferred displacement reaction time is 1-3 hours, and the preferred dosage of the displacement agent is 5-80 g / L. After filtration, the displacement slag produced by the displacement reaction can be sent to the smelting system to recover metal, reducing secondary pollution. To remove impurities such as iron ions introduced during the displacement reaction, hydrogen peroxide and ammonia are used in the primary impurity removal process to remove trace amounts of iron ions and other impurities from the primary crystallization solution. The main reactions are as follows:

[0047] 2Fe2+ +4NH3·H2O+H2O2=4NH4 + +2Fe(OH)3↓,

[0048] To achieve deep removal of iron ions, the primary impurity removal process monitors iron removal by controlling the redox potential and solution pH. The primary impurity removal process requires pre-dissolving the initial coarse crystals in hot water. After displacement impurity removal, ammonia and hydrogen peroxide are added to remove Fe, organic matter, and other impurities. The solid-liquid ratio (msolid:mliquid) is preferably controlled at 1:2~8. The endpoint potential is preferably controlled at 400-640 mV, and the endpoint pH is preferably controlled at 8-10 with the addition of ammonia. After filtration, the solution after the primary impurity removal is transferred to the secondary crystallization process.

[0049] There are no particular limitations on the method for controlling redox potential. For example, when the redox potential decreases, it can be controlled by temporarily adding hydrogen peroxide. It should be noted that a saturated calomel electrode is used as the reference electrode for measuring the potential. Similarly, there are no particular limitations on the method for controlling pH. For example, when the pH decreases, it can be controlled by temporarily adding ammonia.

[0050] The liquid after the first impurity removal undergoes a second freeze-crystallization process, which is not particularly limited. For example, crystallization can be carried out using various known equipment and methods, such as a freeze crystallizer or plate / tube heat exchangers. The preferred freeze-crystallization temperature is -20 to -10°C, more preferably -18 to -12°C, and the preferred freeze-crystallization time is 10 to 20 hours. After filtration, the secondary coarse crystal is transferred to a second impurity removal process, and the residual liquid from the secondary crystallization is returned to the concentration process.

[0051] To remove potential impurities such as cobalt, a secondary impurity removal process is implemented by controlling the redox potential and solution pH. This secondary process requires pre-dissolving the primary coarse crystals in hot water, followed by the addition of ammonia and hydrogen peroxide. The solid-liquid ratio (msolid:mliquid) is preferably controlled at 1:2~8. Hydrogen peroxide is added to control the endpoint potential at 640-1300 mV. It should be noted that a saturated calomel electrode is used as the reference electrode for measuring the potential, and ammonia is added to control the endpoint pH at 8-10. The impurity removal process involves the following reactions:

[0052] 2Co 2+ + H2O2 + 4NH3·H2O = 2Co(OH)3↓ + 4NH4 +

[0053] After the potential and pH stabilize, the solution is filtered, and after a second impurity removal process, it is transferred to the third crystallization process. After the second impurity removal, a third freeze-crystallization is performed. There are no particular limitations; for example, the crystallization reaction can be carried out using various known equipment and methods, such as a freeze crystallizer or plate / tube heat exchangers. The preferred freeze-crystallization temperature is -20 to -10°C, more preferably -18 to -12°C, and the preferred freeze-crystallization time is 10 to 20 hours. After filtration, the residue from the third crystallization is returned to the concentration process. The obtained third crystals are then centrifuged, dehydrated, and dried to obtain high-purity ammonium rheniumate.

[0054] It should be noted that there are no particular limitations on centrifugal dehydration; the rotation speed is typically 1500~5000 r / min, and the dehydration time is typically 5~10 min. Similarly, there are no particular limitations on drying; the preferred drying temperature is typically 60~90℃, and the preferred drying time is 10~20 h. The obtained high-purity ammonium rhenium acid has a purity of over 99.99% and is 4N ammonium rhenium acid.

[0055] The following embodiments of the present invention are shown to illustrate the invention in more detail, but the invention is not limited to the following embodiments at all.

[0056] Example 1

[0057] A complex rhenium-containing solution from a domestic smelter was taken, containing 0.1–0.6 g / L rhenium, 20–100 g / L arsenic, 20–80 g / L copper, 0.1–2 g / L antimony, 0.2–2 g / L bismuth, 0.1–10 g / L iron, 0.1–10 g / L cadmium, 5–80 g / L lead, 0.1–10 g / L zinc, 0.1–0.4 g / L selenium, 0.1–5 g / L tin, and 50–100 g / L sulfuric acid. A certain volume of the solution was taken, and under the condition that the extraction ratio (V organic phase:V liquid) = 1:20, a mixture of N235:2-octanol:kerosene (VN235:V2-octanol:Vkerosene) = 20:20:60 was added. The extraction stage was 6 stages, and extraction was carried out at 25°C for 40 min. The obtained extract phase was first washed with pure water. Ammonia was added under the condition that the extraction ratio (V organic phase:V liquid) = 1:5, and the back-extraction stage was 4 stages. Back-extraction was performed at room temperature for 20 min, and the resulting back-extract was transferred to the concentration process. The back-extract was concentrated at 80℃, with the final concentration specific gravity set at 1.15. During the process, 1 / 40 of the back-extract volume of 10wt% ammonia was added to obtain the concentrated liquid. The concentrated liquid was cooled at -10℃ for 10 h to obtain the first crystallization liquid and the first crude crystal. The first crystallization liquid was returned to the concentration process, and the first crude crystal was prepared at a solid-liquid ratio (m... 固 :m 液The solution was dissolved in hot water at a ratio of 1:4, and 325-mesh iron powder (10 g / L) was added and stirred. The mixture was stirred at room temperature for 1 hour to remove impurities such as copper, antimony, and lead. Hydrogen peroxide and ammonia were then added to control the reaction endpoint potential at 400 mV and the pH at 10, removing organic phase and Fe impurities. The purified solution was cooled at -15°C for 12 hours and dehydrated at 2000 r / min for 7 minutes to obtain secondary coarse crystals and a secondary crystallized solution. The secondary crystallized solution was returned to the concentration process. The secondary coarse crystals were dissolved again in hydrogen peroxide, ammonia, and water, controlling the reaction endpoint potential at 700 mV and the pH at 10. The purified solution was frozen at -12°C for 11 hours and dehydrated at 3000 r / min for 5 minutes to obtain tertiary crystals and a tertiary crystallized solution. The tertiary crystallized solution was returned to the concentration process. Three crystallizations were performed followed by drying at 80℃ for 10 hours to obtain high-purity ammonium perrylate. The obtained ammonium perrylate had a purity of 99.993% and was classified as 4N ammonium perrylate. The rhenium recovery rate throughout the process was 96.27%. Figure 2 As shown.

[0058] Example 2

[0059] The concentrated solution obtained in Example 1 was cooled at -10°C for 10 hours to obtain a first-crystallized solution and a first-crystallized crude solution. The first-crystallized solution was returned to the concentration process. The first-crystallized crude solution was dissolved in hot water at a solid-liquid ratio (msolid:mliquid) of 1:4. 800-mesh iron powder (10 g / L) was added and stirred at room temperature for 1 hour to remove impurities such as copper, antimony, and lead. Hydrogen peroxide and ammonia were then added to control the reaction endpoint potential at 500 mV and the reaction endpoint pH at 10, removing organic phase and Fe impurities. The purified solution was cooled at -15°C for 12 hours and dehydrated at 2000 r / min for 7 minutes to obtain a second-crystallized crude solution and a second-crystallized solution. The second-crystallized solution was returned to the concentration process. The second-crystallized crude solution was dissolved again in hydrogen peroxide, ammonia, and water, controlling the reaction endpoint potential at 800 mV and the reaction endpoint pH at 10. The obtained secondary impurity-removed liquid was cooled at -12℃ for 11 hours, and then dehydrated at 3000 r / min for 5 minutes to obtain tertiary crystallization and the liquid after tertiary crystallization. The liquid after tertiary crystallization was returned to the concentration process. The tertiary crystallization was dried at 80℃ for 10 hours to obtain high-purity ammonium rhenium acid. The obtained ammonium rhenium acid had a purity of 99.994% and was 4N ammonium rhenium acid. The rhenium recovery rate of the entire process was 97.27%.

[0060] Example 3

[0061] The concentrated solution obtained in Example 1 was cooled at -10°C for 10 hours to obtain a primary crystallized solution and a primary coarse crystal. The primary crystallized solution was returned to the concentration process. The primary coarse crystal was dissolved in hot water at a solid-liquid ratio (msolid:mliquid) of 1:4. A mixed displacement agent of 800-mesh iron powder and zinc powder was added and stirred at 10 g / L. The mixture was stirred at room temperature for 1 hour to remove impurities such as copper, antimony, and lead. Hydrogen peroxide and ammonia were then added to control the reaction endpoint potential at 600 mV and the reaction endpoint pH at 10, removing organic phase and Fe impurities. The purified solution was cooled at -15°C for 12 hours and dehydrated at 2000 r / min for 7 minutes to obtain a secondary coarse crystal and a secondary crystallized solution. The secondary crystallized solution was returned to the concentration process. The secondary coarse crystal was dissolved again in hydrogen peroxide, ammonia, and water, controlling the reaction endpoint potential at 900 mV and the reaction endpoint pH at 10. The obtained secondary impurity-removed liquid was cooled at -12℃ for 11 hours, and then dehydrated at 3000 r / min for 5 minutes to obtain tertiary crystallization and the liquid after tertiary crystallization. The liquid after tertiary crystallization was returned to the concentration process. The tertiary crystallization was dried at 80℃ for 10 hours to obtain high-purity ammonium perrhenate. The obtained ammonium perrhenate had a purity of 99.992% and was 4N ammonium perrhenate. The rhenium recovery rate throughout the process was 98.03%.

[0062] Example 4

[0063] The concentrated solution obtained in Example 1 was cooled at -10°C for 10 hours to obtain a first-crystallized solution and a first-crystallized crude solution. The first-crystallized solution was returned to the concentration process. The first-crystallized crude solution was stirred at a solid-liquid ratio (msolid:mliquid) of 1:4 with a mixed displacement agent of 800-mesh iron powder, zinc powder, and aluminum powder added at a displacement agent concentration of 10 g / L. After stirring at room temperature for 1 hour to remove impurities such as copper, antimony, and lead, hydrogen peroxide and ammonia were added to control the reaction endpoint potential at 600 mV and the reaction endpoint pH at 10, removing organic phase and Fe impurities. The obtained purified solution was cooled at -15°C for 12 hours and dehydrated at 2000 r / min for 7 minutes to obtain a second-crystallized crude solution and a second-crystallized solution. The second-crystallized solution was returned to the concentration process. The second-crystallized crude solution was dissolved again with hydrogen peroxide, ammonia, and water, controlling the reaction endpoint potential at 1000 mV and the reaction endpoint pH at 10. The obtained secondary impurity-removed liquid was cooled at -12℃ for 11 hours, and then dehydrated at 3000 r / min for 5 minutes to obtain tertiary crystallization and the liquid after tertiary crystallization. The liquid after tertiary crystallization was returned to the concentration process. The tertiary crystallization was dried at 80℃ for 10 hours to obtain high-purity ammonium perrhenate. The obtained ammonium perrhenate had a purity of 99.997% and was 4N ammonium perrhenate. The rhenium recovery rate throughout the process was 95.76%.

[0064] Example 5

[0065] The concentrated solution obtained in Example 1 was cooled at -10°C for 10 hours. This yielded a first-crystallized solution and a first-crystallized crude solution. The first-crystallized solution was returned to the concentration process. The first-crystallized crude solution was stirred with a mixed displacement agent of 500-mesh iron powder at a solid-liquid ratio (msolid:mliquid) of 10 g / L at room temperature for 1 hour to remove impurities such as copper, antimony, and lead. Hydrogen peroxide and ammonia were then added to control the reaction endpoint potential at 450 mV and the reaction endpoint pH at 10, removing organic phase and Fe impurities. The purified solution was cooled at -15°C for 12 hours and dehydrated at 2000 r / min for 7 minutes to obtain a second-crystallized crude solution and a second-crystallized solution. The second-crystallized solution was returned to the concentration process. The second-crystallized crude solution was dissolved again with hydrogen peroxide, ammonia, and water, controlling the reaction endpoint potential at 1100 mV and the reaction endpoint pH at 10. The obtained secondary impurity-removed liquid was cooled at -12℃ for 11 hours, and then dehydrated at 3000 r / min for 5 minutes to obtain tertiary crystallization and the liquid after tertiary crystallization. The liquid after tertiary crystallization was returned to the concentration process. The tertiary crystallization was dried at 80℃ for 10 hours to obtain high-purity ammonium perrhenate. The obtained ammonium perrhenate had a purity of 99.993% and was 4N ammonium perrhenate. The rhenium recovery rate throughout the process was 96.45%.

[0066] The foregoing has provided a detailed description of a method for preparing high-purity ammonium rheniumate from a complex rhenium-containing solution, as provided in 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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 high-purity ammonium perrylate from complex rhenium-containing solutions, characterized in that, The method specifically includes the following steps: S1) Extraction and back-extraction: A complex rhenium-containing solution is mixed with an organic phase according to a certain extraction ratio. The rhenium-containing organic phase is separated and transferred to the back-extraction process. After the third phase is removed, a back-extraction agent is added to perform separation and back-extraction to obtain the back-extraction solution. S2) Concentration: The back-extraction solution obtained in S1) is heated and concentrated until the reaction endpoint is reached. Ammonia water is added until the endpoint pH is reached, and then the solution is filtered to obtain the concentrated solution. S3) Primary crystallization: After freezing the concentrated liquid obtained in S2) for a certain period of time, primary crude crystals are obtained; S4) First dissolution and impurity removal: Add a certain amount of hot water to the crude crystals obtained in S3) and stir until completely dissolved. Then add a displacement agent to remove impurities for a certain period of time. Add hydrogen peroxide and ammonia water until the endpoint potential and endpoint pH are reached. Filter to obtain the liquid after first impurity removal. The specific process for the primary dissolution and impurity removal in S4) is as follows: hot water is added to dissolve the primary coarse crystals, with a solid-liquid ratio of m. 固 :m 液 =1:2~8; the amount of displacing agent added is 5~80 g / L, and after reacting for 0.5~1.5h, hydrogen peroxide and ammonia are added in sequence to remove impurities; The endpoint potential is controlled by adding hydrogen peroxide to 400-640 mV, and the endpoint pH is controlled by adding ammonia to 8-10; the displacing agent is one or more of iron powder, zinc powder, and aluminum powder. S5) Secondary crystallization: After freezing the liquid obtained from the first purification in S4) for a certain period of time, secondary crude crystals are obtained; S6) Secondary dissolution and impurity removal: Add a certain amount of hot water to the secondary crude crystals obtained in S5) and stir until completely dissolved. Then add hydrogen peroxide and ammonia water to the endpoint potential and endpoint pH to remove impurities from the secondary crude crystals. Filter to obtain the liquid after secondary impurity removal. S7) Three-stage crystallization; the liquid obtained after the second impurity removal in S6) is placed in a freezer, frozen for a certain period of time and then filtered. The obtained three-stage crystals are centrifuged, dehydrated and dried to obtain high-purity ammonium rhenium, which is 4N ammonium rhenium.

2. The method according to claim 1, characterized in that: Compared to extraction with an organic phase, the complex rhenium-containing solution in S1) has the following characteristics: V 有机相 V 液 =1:5~20, with 4~8 extraction stages; The extraction process uses N as the organic extractant. 235 A mixture of 2-octanol and kerosene, in a ratio of V. N235 V 仲辛醇 V 煤油 =20:20:60, the back-extraction process uses ammonia as the back-extraction agent, and the back-extraction is compared with V 有机相 V 液 =1:0.5~10, with 4~8 back-extraction stages.

3. The method according to claim 1, characterized in that, The concentration process in S2) is as follows: the concentration temperature is 70-100℃, the concentration endpoint specific gravity is 1.15-1.20, and the amount of ammonia added is 1 / 30 to 1 / 60 of the volume of the back-extraction liquid.

4. The method according to claim 1, characterized in that, The primary crystallization process in S3) is as follows: the freezing crystallization temperature is -20~-10℃, and the freezing time is 12~20 h.

5. The method according to claim 1, characterized in that, The specific process for secondary crystallization in S5 is as follows: the freezing crystallization temperature is -20~-10℃, and the freezing time is 12~20 h.

6. The method according to claim 1, characterized in that, The specific process for the secondary dissolution and impurity removal in S6) is as follows: hot water, hydrogen peroxide, and ammonia are added sequentially to dissolve the secondary coarse crystals, with a solid-liquid ratio of m. 固 :m 液 =1:2~8; where hydrogen peroxide is added to control the endpoint potential at 640-1300 mV, and ammonia is added to control the endpoint pH at 8-10.

7. The method according to claim 1, characterized in that, The freezing temperature for the three-stage crystallization of S7 is -20~-10℃, and the freezing time is 12~20 h.

8. A 4N ammonium perrylate, characterized in that, The 4N ammonium perrylate is prepared by the method described in any one of claims 1-7.

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