Ammonium rhenate purification and recovery method using electrodialysis combined with ion exchange method

Abstract

This invention relates to the field of hydrometallurgical technology and discloses a method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange. The method first adjusts the pH of the rhenium-containing feed solution, then selectively enriches perrylate ions using electrodialysis to obtain a high-concentration rhenium-rich solution. Subsequently, the rhenium-rich solution is subjected to deep adsorption purification through an anion exchange column. Next, rhenium is eluted from the saturated resin using an eluent to obtain a pure ammonium perrylate solution. Finally, high-purity ammonium perrylate crystals are obtained through evaporation, concentration, cooling, crystallization, and drying. Optionally, the obtained crystals can be recrystallized to further improve purity. This invention ensures the purity and process stability of the rhenium-rich solution obtained in the pre-enrichment stage, improves the overall adsorption capacity, desorption rate, and reliability of the process operation of the resin, and guarantees the stability of the final ammonium perrylate product purity and the economic benefits of the entire process recovery.

Description

Technical Field

[0001] This invention relates to the field of hydrometallurgical technology, specifically to a method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange. Background Technology

[0002] Hydrometallurgy is a method in which ores, mineral concentrates or other raw materials are brought into contact with aqueous solutions or other liquid phases, and through chemical reactions, the useful metals contained in the raw materials are transferred into the liquid phase. The various useful metals contained in the liquid phase are then separated and enriched, and finally recovered in the form of metals or other compounds.

[0003] Currently, this method has several technical challenges in its implementation. During the pre-enrichment treatment via electrodialysis, it is impossible to monitor in real time the membrane fouling or performance degradation caused by impurity ions or colloidal substances in the feed solution. When the selectivity of the ion exchange membrane decreases or the resistance increases, the separation of rhenium ions from impurity anions will be incomplete, leading to fluctuations in the purity of the rhenium-enriched solution and a decrease in recovery efficiency. At the same time, during ion exchange adsorption and desorption, it is impossible to ensure that the fluid distribution in the resin adsorption column is always uniform and free from channeling or dead zones. This can cause premature resin penetration or incomplete desorption in some areas, affecting the overall adsorption capacity and desorption rate of rhenium. Furthermore, small deviations in operating parameters such as flow rate and temperature cannot be corrected in real time.

[0004] Therefore, a method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange is proposed to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange. This method solves the problems mentioned in the background art, such as the inability to monitor in real time the membrane fouling or performance degradation caused by impurity ions or colloidal substances in the feed solution, and the inability to ensure that the fluid distribution in the resin adsorption column is always uniform and free from channeling or dead zones.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange, wherein the recovery method includes the following steps: Step 1: Preparation of raw material solution. After leaching and filtering the rhenium-containing material, an initial solution containing rhenium ions is obtained. The pH value of the solution is adjusted to 8-10 to obtain the ammonium rhenium-containing raw material solution to be treated. Step 2: Electrodialysis pre-enrichment. The raw material solution is injected into the feed chamber of the electrodialysis device and electrodialysis is performed under the action of a DC electric field. This allows the rhenium ions to selectively migrate and enrich in the concentration chamber, resulting in a rhenium-rich solution. Impurity anions remain in the dilute chamber or migrate to the electrode chamber to form a rhenium-lean solution. Step 3: Deep purification by ion exchange. The rhenium-rich solution is passed into an ion exchange column packed with anion exchange resin at a specific flow rate, so that rhenium ions are selectively adsorbed on the resin phase. The effluent is collected until it breaks through to obtain saturated resin loaded with rhenium. Step 4: Resin regeneration and desorption. The saturated resin is subjected to countercurrent desorption using the desorption solution, and the desorption solution rich in high concentration of rhenium ions is collected. Step 5: Crystallization and post-processing. Adjust the pH and concentration of the eluent, and then concentrate by evaporation, cool and crystallize, separate solid and liquid, and dry to obtain high-purity ammonium perrylate crystals.

[0007] Preferably, in step one, the rhenium-containing material is at least one of the following: molybdenum concentrate roasting flue gas leaching liquid, rhenium-containing waste catalyst leachate, rhenium-containing alloy dissolving liquid, or rhenium-containing wastewater. The rhenium in the raw material solution exists in the form of rhenium ions, with a concentration range of 0.5 g / L to 10 g / L. The reagent used to adjust the pH is one of ammonia water, ammonium hydroxide solution, or ammonium carbonate solution.

[0008] Preferably, in step two, the electrodialysis device uses a homogeneous anion exchange membrane to divide the compartment into an anode compartment, a cathode compartment, at least one concentrate compartment, and at least one dilute compartment. The operating conditions for the electrodialysis treatment are: a DC voltage gradient of 5V / membrane pair to 15V / membrane pair, a feed solution flow rate of 5cm / s to 20cm / s in the feed compartment, and an operating temperature of 20℃ to 40℃. The electrodialysis treatment continues until the rhenium concentration in the dilute compartment effluent drops to below 5% of the initial concentration of the feed solution, thus obtaining the rhenium-rich solution with a rhenium concentration enriched to 15g / L to 50g / L.

[0009] Preferably, the homogeneous anion exchange membrane is a quaternary ammonium anion exchange membrane with a sheet resistivity of less than 3 Ω·cm. 2 The ion exchange capacity is greater than 1.8 mmol / g. During the electrodialysis process, a sodium sulfate solution with a concentration of 0.1 mol / L to 0.5 mol / L is circulated into the electrode chamber as the electrode solution.

[0010] Preferably, in step three, the anion exchange resin is a macroporous weakly basic anion exchange resin with tertiary or secondary amine groups as functional groups, a resin particle size range of 0.3 mm to 1.2 mm, a crosslinking degree of 6% to 10%, a diameter-to-height ratio of 1:5 to 1:10 for the ion exchange column, and a flow rate of 2 to 5 times the resin bed volume per hour for the rhenium-rich solution introduced into the ion exchange column.

[0011] Preferably, the ion exchange column is a multi-column series or parallel system. When two columns are connected in series, the first column serves as the main adsorption column and the second column serves as the guard column. The adsorption process is carried out at room temperature. When the rhenium concentration detected in the effluent from the guard column reaches 1%-5% of the feed concentration, it is determined that the main adsorption column has broken through, and the column system is switched and regeneration is performed.

[0012] Preferably, in step four, the desorption solution is one of the following: an ammonia solution with a concentration of 5wt%-15wt%, an ammonium nitrate solution with a concentration of 0.5mol / L-2mol / L, or an ammonium thiocyanate solution with a concentration of 1mol / L-4mol / L. The desorption flow rate is 0.5 volumes / hour to 2 volumes / hour, the amount of desorbent is 2 to 5 times the volume of the resin bed, and the desorption method is a multi-stage step desorption, including first washing the resin bed with deionized water or a low-concentration eluent to remove residual impurities, and then using the desorption solution for main desorption. The effluent from the main desorption stage is collected as the rhenium-rich desorption solution.

[0013] Preferably, the desorption process is carried out at a temperature of 30℃-50℃. After desorption is completed, the resin is regenerated using a sodium hydroxide solution with a concentration of 3wt%-8wt% or a sodium carbonate solution with a concentration of 2wt%-5wt%. The amount of regenerated solution is 1 to 3 times the volume of the resin bed. Then, the resin is rinsed with deionized water until the effluent is neutral, so that the resin is restored to the free alkaline form or bicarbonate form for the next adsorption cycle.

[0014] Preferably, in step five, the crystallization and post-processing includes: firstly, evaporating and concentrating the rhenium-rich eluent at 50℃-70℃ and a vacuum of -0.08MPa to -0.095MPa until the ammonium rheniumate concentration is close to the saturation point; then, slowly cooling the concentrated solution to 0℃-10℃ at a rate of 0.5℃ / min-1℃ / min, and aging it for 1 hour to 3 hours to induce crystal precipitation; then, performing solid-liquid separation by centrifugation or filtration; rinsing the obtained wet crystals with a mixture of deionized water and ethanol; and finally, drying the washed crystals in a vacuum drying oven at 50℃-80℃ for 4 hours to 8 hours to obtain ammonium rheniumate crystals with a purity greater than 99.9%.

[0015] Preferably, the purification method further includes a recrystallization purification step: dissolving the high-purity ammonium perrylate crystals in hot deionized water at 60℃-80℃ to prepare a supersaturated solution, then adding 0.1%-0.5% of ammonium perrylate seed crystals by volume, and cooling the solution to 5℃-15℃ at a rate of 0.2℃ / min-0.5℃ / min under uniform stirring to allow the crystals to grow in a directional manner. The precipitated crystals are then filtered, washed with an ice-water-ethanol mixture, and vacuum dried at 60℃-70℃ under an inert atmosphere to finally obtain a high-purity ammonium perrylate product with a total impurity content of less than 10ppm. The recrystallization step can be repeated 1-3 times, and the hot deionized water used for each dissolution needs to be pre-purified with high-purity nitrogen to remove dissolved oxygen.

[0016] Compared with the prior art, the present invention provides a method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange, which has the following advantages: 1. In this invention, by combining the electrodialysis pre-enrichment process with an integrated online monitoring system, the electrochemical performance and contamination status of the ion exchange membrane can be evaluated in real time, thereby ensuring that rhenium ions and impurity anions are separated under the action of an electric field. This solves the problem of incomplete separation and decreased recovery efficiency caused by membrane performance fluctuations, and ensures the purity and process stability of the rhenium-rich solution obtained in the pre-enrichment stage.

[0017] 2. In this invention, by optimizing the internal structure of the ion exchange column and cooperating with the fluid control and process parameter monitoring system, it is possible to ensure that the rhenium-rich solution is uniformly distributed in the resin bed and to correct minor deviations in key parameters such as flow rate and temperature during adsorption and desorption in real time. This prevents channeling, dead zones, and local resin failure, thereby improving the overall adsorption capacity, desorption rate, and reliability of the process operation.

[0018] 3. In this invention, by constructing an intelligent feedback and adaptive control system connecting electrodialysis and ion exchange, the process parameters of the upstream and downstream processes can be dynamically adjusted according to the real-time monitoring of the raw material composition and intermediate solution properties, so that the entire series process is always kept in the optimal operating window. This enhances the process flow's adaptability to complex raw material fluctuations, ensures the stability of the purity of the final ammonium perrylate product, and guarantees the economic benefits of the entire process recovery. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1: A method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange. The recovery method includes the following steps: Step 1: Preparation of raw material solution. After leaching and filtering the rhenium-containing material, an initial solution containing rhenium ions is obtained. The pH value of the solution is adjusted to 8 to obtain the ammonium rhenium-containing raw material solution to be treated. Step 2: Electrodialysis pre-enrichment. The raw material solution is injected into the feed chamber of the electrodialysis device and electrodialysis is performed under the action of a DC electric field. This allows the rhenium ions to selectively migrate and enrich in the concentration chamber, resulting in a rhenium-rich solution. Impurity anions remain in the dilute chamber or migrate to the electrode chamber to form a rhenium-lean solution. Step 3: Deep purification by ion exchange. The rhenium-rich solution is passed into an ion exchange column packed with anion exchange resin at a specific flow rate, so that the rhenium ions are selectively adsorbed on the resin phase. The effluent is collected until it breaks through to obtain saturated resin loaded with rhenium. Step 4: Resin regeneration and desorption. The saturated resin is subjected to countercurrent desorption using the desorption solution, and the desorption solution rich in high concentration of rhenium ions is collected. Step 5: Crystallization and post-treatment. Adjust the pH and concentration of the eluent, and then concentrate by evaporation, cool and crystallize, separate solid and liquid, and dry to obtain high-purity ammonium perrylate crystals.

[0021] In step one, the rhenium-containing material is the leaching liquid from the roasting flue gas of molybdenum concentrate. The rhenium in the raw material solution exists in the form of rhenium ions with a concentration of 0.5 g / L. The reagent used to adjust the pH is ammonia water.

[0022] In step two, the electrodialysis apparatus uses a homogeneous anion exchange membrane to divide the compartment into an anode compartment, a cathode compartment, at least one concentrate compartment, and at least one dilute compartment. The operating conditions for electrodialysis are: a DC voltage gradient of 5V / membrane pair, a feed solution flow rate of 5cm / s in the feed compartment, and an operating temperature of 20℃. The electrodialysis process continues until the rhenium concentration in the dilute compartment effluent drops below 5% of the initial concentration of the feed solution, resulting in a rhenium-rich solution with a rhenium concentration enriched to 15g / L.

[0023] The homogeneous anion exchange membrane is a quaternary ammonium type anion exchange membrane with a sheet resistivity of less than 3 Ω·cm. 2 With an ion exchange capacity greater than 1.8 mmol / g, a sodium sulfate solution with a concentration of 0.1 mol / L is circulated into the electrode chamber as the electrode solution during the electrodialysis process.

[0024] In step three, the anion exchange resin is a macroporous weakly basic anion exchange resin with tertiary or secondary amine groups as its functional groups. The resin particle size is 0.3 mm, the degree of crosslinking is 6%, the diameter-to-height ratio of the ion exchange column is 1:5, and the flow rate of the rhenium-rich solution into the ion exchange column is twice the resin bed volume / hour.

[0025] The ion exchange column is a multi-column series or parallel system. When two columns are connected in series, the first column is used as the main adsorption column and the second column is used as the guard column. The adsorption process is carried out at room temperature. When the rhenium concentration in the effluent of the guard column reaches 1% of the feed concentration, it is determined that the main adsorption column has broken through. The column system is then switched and regeneration is performed.

[0026] In step four, the desorption solution is a 5 wt% ammonia solution, the desorption flow rate is 0.5 volumes / hour, the amount of desorbent is twice the volume of the resin bed, and the desorption method is a multi-stage step desorption, which includes first washing the resin bed with deionized water or a low-concentration eluent to remove residual impurities, and then using the desorption solution for main desorption. The effluent from the main desorption stage is collected as the rhenium-rich desorption solution.

[0027] The desorption process is carried out at a temperature of 30℃. After desorption is completed, the resin is regenerated by using a 3wt% sodium hydroxide solution or a 2wt% sodium carbonate solution. The amount of regenerated solution is 1 times the volume of the resin bed. Then, the resin is rinsed with deionized water until the effluent is neutral, so that the resin is restored to the free basic form or bicarbonate form for the next adsorption cycle.

[0028] In step five, crystallization and post-processing include: first, evaporating and concentrating the rhenium-rich eluent at 50°C and a vacuum of -0.08 MPa until the ammonium perrylate concentration is close to the saturation point; then, slowly cooling the concentrated solution to 0°C at a rate of 0.5°C / min and aging it for 1 hour to induce crystal precipitation; then, performing solid-liquid separation by centrifugation or filtration; rinsing the obtained wet crystals with a mixture of deionized water and ethanol; finally, drying the washed crystals in a vacuum drying oven at 50°C for 4 hours to obtain ammonium perrylate crystals with a purity greater than 99.9%.

[0029] The purification method further includes a recrystallization purification step: high-purity ammonium perrylate crystals are dissolved in hot deionized water at 60°C to prepare a supersaturated solution. Then, 0.1% of the solution volume of ammonium perrylate seed crystals are added, and the solution is cooled to 5°C at a rate of 0.2°C / min under uniform stirring to allow the crystals to grow in a directional manner. The precipitated crystals are filtered, washed with an ice-water-ethanol mixture, and vacuum dried at 60°C under an inert atmosphere to finally obtain a high-purity ammonium perrylate product with a total impurity content of less than 10 ppm. The recrystallization step can be repeated once, and the hot deionized water used for each dissolution must be pre-purified with high-purity nitrogen to remove dissolved oxygen.

[0030] Example 2: A method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange. The recovery method includes the following steps: Step 1: Preparation of raw material solution. After leaching and filtering the rhenium-containing material, an initial solution containing rhenium ions is obtained. The pH value of the solution is adjusted to 9 to obtain the ammonium rhenium-containing raw material solution to be treated. Step 2: Electrodialysis pre-enrichment. The raw material solution is injected into the feed chamber of the electrodialysis device and electrodialysis is performed under the action of a DC electric field. This allows the rhenium ions to selectively migrate and enrich in the concentration chamber, resulting in a rhenium-rich solution. Impurity anions remain in the dilute chamber or migrate to the electrode chamber to form a rhenium-lean solution. Step 3: Deep purification by ion exchange. The rhenium-rich solution is passed into an ion exchange column packed with anion exchange resin at a specific flow rate, so that the rhenium ions are selectively adsorbed on the resin phase. The effluent is collected until it breaks through to obtain saturated resin loaded with rhenium. Step 4: Resin regeneration and desorption. The saturated resin is subjected to countercurrent desorption using the desorption solution, and the desorption solution rich in high concentration of rhenium ions is collected. Step 5: Crystallization and post-treatment. Adjust the pH and concentration of the eluent, and then concentrate by evaporation, cool and crystallize, separate solid and liquid, and dry to obtain high-purity ammonium perrylate crystals.

[0031] In step one, the rhenium-containing material is the leachate of spent catalyst containing rhenium. Rhenium exists in the raw material solution in the form of rhenium ions, with a concentration of 5.25 g / L. The reagent used to adjust the pH is ammonium hydroxide solution.

[0032] In step two, the electrodialysis apparatus uses a homogeneous anion exchange membrane to divide the compartment into an anode compartment, a cathode compartment, at least one concentrate compartment, and at least one dilute compartment. The operating conditions for electrodialysis are as follows: DC voltage gradient of 10V / membrane pair, flow rate of feed solution in feed compartment of 12.5cm / s, operating temperature of 30℃, and electrodialysis is carried out until the rhenium concentration in the dilute compartment effluent drops to less than 5% of the initial concentration of feed solution, thus obtaining a rhenium-rich solution with a rhenium concentration enriched to 32.5g / L.

[0033] The homogeneous anion exchange membrane is a quaternary ammonium type anion exchange membrane with a sheet resistivity of less than 3 Ω·cm. 2 With an ion exchange capacity greater than 1.8 mmol / g, a sodium sulfate solution with a concentration of 0.3 mol / L is circulated into the electrode chamber as the electrode solution during the electrodialysis process.

[0034] In step three, the anion exchange resin is a macroporous weakly basic anion exchange resin with tertiary or secondary amine groups as its functional groups. The resin particle size is 0.75 mm, the degree of crosslinking is 8%, the diameter-to-height ratio of the ion exchange column is 2:15, and the flow rate of the rhenium-rich solution into the ion exchange column is 3.5 times the resin bed volume / hour.

[0035] The ion exchange column is a multi-column series or parallel system. When two columns are connected in series, the first column is used as the main adsorption column and the second column is used as the guard column. The adsorption process is carried out at room temperature. When the rhenium concentration in the effluent of the guard column reaches 3% of the feed concentration, it is determined that the main adsorption column has broken through. The column system is then switched and regeneration is performed.

[0036] In step four, the desorption solution is an ammonium nitrate solution with a concentration of 1.25 mol / L, the desorption flow rate is 1.75 volumes / hour, the amount of desorbent is 3.5 times the volume of the resin bed, and the desorption method is a multi-stage step desorption, which includes first washing the resin bed with deionized water or a low-concentration eluent to remove residual impurities, and then using the desorption solution for main desorption. The effluent from the main desorption stage is collected as the rhenium-rich desorption solution.

[0037] The desorption process is carried out at a temperature of 40℃. After desorption is completed, the resin is regenerated by using a 5.5wt% sodium hydroxide solution or a 3.5wt% sodium carbonate solution. The amount of regenerated solution is twice the volume of the resin bed. Then, the resin is rinsed with deionized water until the effluent is neutral, so that the resin is restored to the free basic form or bicarbonate form for the next adsorption cycle.

[0038] In step five, crystallization and post-processing include: first, evaporating and concentrating the rhenium-rich eluent at 60°C and a vacuum of -0.0875 MPa until the ammonium perrhenate concentration is close to the saturation point; then, slowly cooling the concentrated solution to 5°C at a rate of 0.751°C / min and aging it for 2 hours to induce crystal precipitation; then, separating the solid and liquid by centrifugation or filtration; washing the obtained wet crystals with a mixture of deionized water and ethanol; and finally, drying the washed crystals in a vacuum drying oven at 65°C for 6 hours to obtain ammonium perrhenate crystals with a purity greater than 99.9%.

[0039] The purification method further includes a recrystallization purification step: high-purity ammonium perrylate crystals are dissolved in hot deionized water at 70°C to prepare a supersaturated solution. Then, 0.3% of the solution volume of ammonium perrylate seed crystals are added, and the temperature is gradually reduced to 10°C at a rate of 0.35°C / min under uniform stirring to allow the crystals to grow in a directional manner. The precipitated crystals are filtered, washed with an ice-water-ethanol mixture, and vacuum dried at 65°C under an inert atmosphere to finally obtain a high-purity ammonium perrylate product with a total impurity content of less than 10 ppm. The recrystallization step can be repeated twice, and each time the hot deionized water used for dissolution needs to be pre-purified with high-purity nitrogen to remove dissolved oxygen.

[0040] Example 3: A method for purifying and recovering ammonium perrylate using a combination of electrodialysis and ion exchange. The recovery method includes the following steps: Step 1: Preparation of raw material solution. After leaching and filtering the rhenium-containing material, an initial solution containing rhenium ions is obtained. The pH value of the solution is adjusted to 10 to obtain the ammonium rhenium-containing raw material solution to be treated. Step 2: Electrodialysis pre-enrichment. The raw material solution is injected into the feed chamber of the electrodialysis device and electrodialysis is performed under the action of a DC electric field. This allows the rhenium ions to selectively migrate and enrich in the concentration chamber, resulting in a rhenium-rich solution. Impurity anions remain in the dilute chamber or migrate to the electrode chamber to form a rhenium-lean solution. Step 3: Deep purification by ion exchange. The rhenium-rich solution is passed into an ion exchange column packed with anion exchange resin at a specific flow rate, so that the rhenium ions are selectively adsorbed on the resin phase. The effluent is collected until it breaks through to obtain saturated resin loaded with rhenium. Step 4: Resin regeneration and desorption. The saturated resin is desorbed countercurrently using a desorption solution, and the desorption solution rich in high concentrations of rhenium ions is collected. Step 5: Crystallization and post-treatment. Adjust the pH and concentration of the eluent, and then concentrate by evaporation, cool and crystallize, separate solid and liquid, and dry to obtain high-purity ammonium perrylate crystals.

[0041] In step one, the rhenium-containing material is rhenium-containing wastewater. Rhenium exists in the raw material solution in the form of rhenium ions with a concentration of 10 g / L. The reagent used to adjust the pH is ammonium carbonate solution.

[0042] In step two, the electrodialysis apparatus uses a homogeneous anion exchange membrane to divide the compartment into an anode compartment, a cathode compartment, at least one concentrate compartment, and at least one dilute compartment. The operating conditions for electrodialysis are: a DC voltage gradient of 15V / membrane pair, a feed solution flow rate of 20cm / s in the feed compartment, and an operating temperature of 40℃. The electrodialysis process continues until the rhenium concentration in the dilute compartment effluent drops to below 5% of the initial concentration of the feed solution, resulting in a rhenium-rich solution with a rhenium concentration enriched to 50g / L.

[0043] The homogeneous anion exchange membrane is a quaternary ammonium type anion exchange membrane with a sheet resistivity of less than 3 Ω·cm. 2 With an ion exchange capacity greater than 1.8 mmol / g, a sodium sulfate solution with a concentration of 0.5 mol / L is circulated into the electrode chamber as the electrode solution during the electrodialysis process.

[0044] In step three, the anion exchange resin is a macroporous weakly basic anion exchange resin with tertiary or secondary amine groups as its functional groups. The resin particle size is 1.2 mm, the degree of crosslinking is 10%, the diameter-to-height ratio of the ion exchange column is 1:10, and the flow rate of the rhenium-rich solution into the ion exchange column is 5 times the resin bed volume / hour.

[0045] The ion exchange column is a multi-column series or parallel system. When two columns are connected in series, the first column is used as the main adsorption column and the second column is used as the guard column. The adsorption process is carried out at room temperature. When the rhenium concentration in the effluent of the guard column reaches 5% of the feed concentration, it is determined that the main adsorption column has broken through. The column system is then switched and regeneration is performed.

[0046] In step four, the desorption solution is one of the 4 mol / L ammonium thiocyanate solutions, the desorption flow rate is 2 volumes / hour, the amount of desorbent is 5 times the volume of the resin bed, and the desorption method is multi-stage step desorption, which includes first washing the resin bed with deionized water or low-concentration eluent to remove residual impurities, and then using the desorption solution for main desorption. The effluent from the main desorption stage is collected as rhenium-rich desorption solution.

[0047] The desorption process is carried out at a temperature of 50℃. After desorption is completed, the resin is regenerated by using an 8wt% sodium hydroxide solution or a 5wt% sodium carbonate solution. The amount of regenerated solution is 3 times the volume of the resin bed. Then, the resin is rinsed with deionized water until the effluent is neutral, so that the resin is restored to the free alkaline form or bicarbonate form for the next adsorption cycle.

[0048] In step five, crystallization and post-processing include: first, evaporating and concentrating the rhenium-rich eluent at 70°C and a vacuum of -0.095 MPa until the ammonium perrhenate concentration is close to the saturation point; then, slowly cooling the concentrated solution to 10°C at a rate of 1°C / min and aging it for 3 hours to induce crystal precipitation; then, separating the solid and liquid by centrifugation or filtration; rinsing the obtained wet crystals with a mixture of deionized water and ethanol; and finally, drying the washed crystals in a vacuum drying oven at 80°C for 8 hours to obtain ammonium perrhenate crystals with a purity greater than 99.9%.

[0049] The purification method further includes a recrystallization purification step: high-purity ammonium perrylate crystals are dissolved in hot deionized water at 80°C to prepare a supersaturated solution. Then, 0.5% of the solution volume of ammonium perrylate seed crystals are added, and the temperature is programmed to decrease to 15°C at a rate of 0.5°C / min under uniform stirring to allow the crystals to grow in a directional manner. The precipitated crystals are filtered, washed with an ice-water-ethanol mixture, and vacuum dried at 70°C under an inert atmosphere to finally obtain a high-purity ammonium perrylate product with a total impurity content of less than 10 ppm. The recrystallization step can be repeated 3 times, and each time the hot deionized water used for dissolution needs to be pre-purified with high-purity nitrogen to remove dissolved oxygen.

[0050] Comparative Example 1: The difference between this comparative example and Example 1 is that in the recovery of ammonium perrylate, the electrodialysis pre-enrichment step was not used in this comparative example, and the low-concentration rhenium-containing raw material solution was directly passed into the ion exchange column for adsorption. Comparative Example 2 differs from Example 2 in that: in recovering ammonium perrylate, this comparative example did not use the ion exchange deep purification step, but only concentrated the raw material solution through electrodialysis before crystallization; Comparative Example 3 differs from Example 3 in that the order of electrodialysis and ion exchange is reversed when recovering ammonium rhenium in this comparative example. That is, ion exchange adsorption-desorption is performed first to obtain a high-concentration rhenium solution, and then the solution is subjected to electrodialysis treatment.

[0051] The performance of the ammonium perrylate purification and recovery methods using a combination of electrodialysis and ion exchange in Examples 1-3 and Comparative Examples 1-3 was tested. The test items and methods are as follows: Recovery rate test: Determine the percentage of rhenium mass in the final product ammonium perrylate crystals to the total rhenium mass in the feed solution, and calculate the rhenium recovery rate of the entire process; Product purity testing: Inductively coupled plasma mass spectrometry was used to analyze the content of key impurity elements in the final ammonium perrylate crystals in order to calculate the purity of the main component; Process energy consumption assessment: Record the DC power consumption of the electrodialysis process and the reagent consumption and energy consumption of the ion exchange column regeneration process, and convert them into the comprehensive energy consumption per unit mass of ammonium perrylate product; Resin performance stability test: After multiple consecutive adsorption-desorption cycles, the changes in the saturated adsorption capacity and desorption rate of the anion exchange resin for rhenium ions were measured to evaluate the resin's service life. Impurity separation efficiency test: The concentration of impurity anions in the rhenium-rich solution in the concentrated chamber and the rhenium-lean solution in the dilute chamber after electrodialysis treatment was analyzed by ion chromatography, and the separation coefficient between rhenium and the main impurities was calculated.

[0052] The test data of the ammonium perrylate purification and recovery methods using a combination of electrodialysis and ion exchange in Examples 1-3 and Comparative Examples 1-3 are recorded in the table below:

[0053] Comparison and analysis of the data in the table show that the ammonium permanganate purification and recovery method using a combination of electrodialysis and ion exchange in Examples 1-3 is superior to that in Comparative Examples 1-3. This indicates that by combining the electrodialysis pre-enrichment process with an integrated online monitoring system, the electrochemical performance and contamination status of the ion exchange membrane can be evaluated in real time, thereby ensuring the separation of permanganate ions and impurity anions under the action of an electric field. This solves the problem of incomplete separation and decreased recovery efficiency caused by membrane performance fluctuations, ensuring the purity and process stability of the permanganate-rich solution obtained in the pre-enrichment stage. Furthermore, by optimizing the internal structure of the ion exchange column and coordinating fluid control with… The process parameter monitoring system ensures uniform distribution of rhenium-rich solution within the resin bed and corrects minor deviations in key parameters such as flow rate and temperature during adsorption and desorption in real time. This prevents channeling, dead zones, and localized resin failure, improving the overall adsorption capacity, desorption rate, and reliability of the process. By constructing an intelligent feedback and adaptive control system connecting electrodialysis and ion exchange, the system dynamically adjusts the process parameters of upstream and downstream processes based on real-time monitoring of raw material composition and intermediate solution properties. This keeps the entire series process within the optimal operating window, enhancing the process's adaptability to complex raw material fluctuations and ensuring the stability of the final ammonium rheniumate product purity and the economic benefits of the entire recovery process.

[0054] By comparing and analyzing the relevant data in the table, it can be seen that the ammonium perrylate purification and recovery method of the present invention, which combines electrodialysis and ion exchange, has superior overall performance.

[0055] In the description of this specification, the references to terms such as "an embodiment," "example," and "specific example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. The preferred embodiments of the present invention disclosed above are merely for the purpose of illustrating the invention. The preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for recovering ammonium perrylate using a combination of electrodialysis and ion exchange, characterized in that, The recycling method includes the following steps: Step 1: Preparation of raw material solution. After leaching and filtering the rhenium-containing material, an initial solution containing rhenium ions is obtained. The pH value of the solution is adjusted to 8-10 to obtain the ammonium rhenium-containing raw material solution to be treated. Step 2: Electrodialysis pre-enrichment. The raw material solution is injected into the feed chamber of the electrodialysis device and electrodialysis is performed under the action of a DC electric field. This allows the rhenium ions to selectively migrate and enrich in the concentration chamber, resulting in a rhenium-rich solution. Impurity anions remain in the dilute chamber or migrate to the electrode chamber to form a rhenium-lean solution. Step 3: Deep purification by ion exchange. The rhenium-rich solution is passed into an ion exchange column packed with anion exchange resin at a specific flow rate, so that rhenium ions are selectively adsorbed on the resin phase. The effluent is collected until it breaks through to obtain saturated resin loaded with rhenium. Step 4: Resin regeneration and desorption. The saturated resin is subjected to countercurrent desorption using the desorption solution, and the desorption solution rich in high concentration of rhenium ions is collected. Step 5: Crystallization and post-processing. Adjust the pH and concentration of the eluent, and then concentrate by evaporation, cool and crystallize, separate solid and liquid, and dry to obtain high-purity ammonium perrylate crystals.

2. The ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in claim 1, characterized in that, In step one, the rhenium-containing material is at least one of the following: molybdenum concentrate roasting flue gas leaching liquid, rhenium-containing waste catalyst leachate, rhenium-containing alloy solution, or rhenium-containing wastewater. The rhenium in the raw material solution exists in the form of rhenium ions, with a concentration range of 0.5 g / L to 10 g / L. The reagent used to adjust the pH is one of ammonia water, ammonium hydroxide solution, or ammonium carbonate solution.

3. The ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in claim 1, characterized in that, In step two, the electrodialysis device uses a homogeneous anion exchange membrane to divide the compartment into an anode compartment, a cathode compartment, at least one concentration compartment, and at least one dilute compartment. The operating conditions for the electrodialysis treatment are: a DC voltage gradient of 5V / membrane pair to 15V / membrane pair, a flow rate of the feed solution in the feed compartment of 5cm / s to 20cm / s, and an operating temperature of 20℃ to 40℃. The electrodialysis treatment continues until the rhenium concentration in the dilute compartment effluent drops to below 5% of the initial concentration of the feed solution, thus obtaining the rhenium-rich solution with a rhenium concentration enriched to 15g / L to 50g / L.

4. The ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in claim 3, characterized in that, The homogeneous anion exchange membrane is a quaternary ammonium type anion exchange membrane with a sheet resistivity of less than 3 Ω·cm. 2 The ion exchange capacity is greater than 1.8 mmol / g. During the electrodialysis process, a sodium sulfate solution with a concentration of 0.1 mol / L to 0.5 mol / L is circulated into the electrode chamber as the electrode solution.

5. The ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in claim 1, characterized in that, In step three, the anion exchange resin is a macroporous weakly basic anion exchange resin with tertiary or secondary amine groups as its functional groups. The resin particle size ranges from 0.3 mm to 1.2 mm, and the degree of crosslinking is 6% to 10%. The diameter-to-height ratio of the ion exchange column is 1:5 to 1:10, and the flow rate of the rhenium-rich solution into the ion exchange column is 2 to 5 times the resin bed volume per hour.

6. The ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in claim 5, characterized in that, The ion exchange column is a multi-column series or parallel system. When two columns are connected in series, the first column is used as the main adsorption column and the second column is used as the guard column. The adsorption process is carried out at room temperature. When the rhenium concentration detected in the effluent of the guard column reaches 1%-5% of the feed concentration, it is determined that the main adsorption column has broken through, and the column system is switched and regeneration is performed.

7. The ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in claim 1, characterized in that, In step four, the eluent is one of the following: an ammonia solution with a concentration of 5wt%-15wt%, an ammonium nitrate solution with a concentration of 0.5mol / L-2mol / L, or an ammonium thiocyanate solution with a concentration of 1mol / L-4mol / L. The desorption flow rate is 0.5 volumes / hour to 2 volumes / hour, the amount of desorbent is 2 to 5 times the volume of the resin bed, and the desorption method is a multi-stage step desorption, which includes first washing the resin bed with deionized water or a low-concentration eluent to remove residual impurities, and then using the eluent for main desorption. The effluent from the main desorption stage is collected as the rhenium-rich desorption solution.

8. The ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in claim 7, characterized in that, The desorption process is carried out at a temperature of 30℃-50℃. After desorption is completed, the resin is regenerated by using a sodium hydroxide solution with a concentration of 3wt%-8wt% or a sodium carbonate solution with a concentration of 2wt%-5wt%. The amount of regenerated solution is 1 to 3 times the volume of the resin bed. Then, the resin is rinsed with deionized water until the effluent is neutral, so that the resin is restored to the free basic form or bicarbonate form for the next adsorption cycle.

9. The ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in claim 1, characterized in that, In step five, the crystallization and post-processing include: firstly, evaporating and concentrating the rhenium-rich eluent at 50℃-70℃ and a vacuum of -0.08MPa to -0.095MPa until the ammonium rheniumate concentration is close to the saturation point; then, slowly cooling the concentrated solution to 0℃-10℃ at a rate of 0.5℃ / min-1℃ / min and aging it for 1-3 hours to induce crystal precipitation; then, performing solid-liquid separation by centrifugation or filtration; rinsing the obtained wet crystals with a mixture of deionized water and ethanol; and finally, drying the washed crystals in a vacuum drying oven at 50℃-80℃ for 4-8 hours to obtain ammonium rheniumate crystals with a purity greater than 99.9%.

10. A method for purifying ammonium perrylate using a combination of electrodialysis and ion exchange, wherein after obtaining ammonium perrylate crystals using the ammonium perrylate recovery method using a combination of electrodialysis and ion exchange as described in any one of claims 1-9, the method is characterized in that... The process further includes a recrystallization purification step: the high-purity ammonium perrhenate crystals are dissolved in hot deionized water at 60℃-80℃ to prepare a supersaturated solution. Then, 0.1%-0.5% of the solution volume of ammonium perrhenate seed crystals are added, and the temperature is programmed to decrease to 5℃-15℃ at a rate of 0.2℃ / min-0.5℃ / min under uniform stirring to allow the crystals to grow in a directional manner. The precipitated crystals are filtered, washed with an ice-water-ethanol mixture, and vacuum dried at 60℃-70℃ under an inert atmosphere to finally obtain a high-purity ammonium perrhenate product with a total impurity content of less than 10ppm. The recrystallization step can be repeated 1-3 times, and the hot deionized water used for each dissolution needs to be pre-purified with high-purity nitrogen to remove dissolved oxygen.

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