A rhenium extractant, a preparation method thereof and a method for extracting and separating rhenium
By using a rhenium extractant composed of secondary amines and diphosphorus oxides, and through countercurrent extraction and back-extraction methods, the problems of low efficiency and high cost in existing rhenium separation methods are solved, achieving efficient, economical and environmentally friendly rhenium separation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHENGZHOU UNIV
- Filing Date
- 2025-01-24
- Publication Date
- 2026-06-16
AI Technical Summary
Existing rhenium separation methods suffer from problems such as low extraction efficiency, high extractant cost, and large wastewater discharge, which limit their industrial application.
Using a rhenium extractant composed of secondary amines and diphosphorus oxides, rhenium salts are directly extracted through countercurrent extraction and back-extraction. This method eliminates the need for saponification or activation of the extractant and allows for reuse, thus reducing costs.
It achieves efficient, economical, and environmentally friendly rhenium separation, with a rhenium extraction rate of ≥90% and a purity of ≥93%, reducing production and usage costs and making it suitable for large-scale industrial application.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of metal extraction and separation in hydrometallurgy, and particularly to a rhenium extractant, its preparation method, and a method for extracting and separating rhenium. Background Technology
[0002] Rhenium is an extremely rare metallic element on Earth, with very low abundance in the Earth's crust. It is one of the least abundant non-ferrous metals on Earth. During Earth's evolution, it rarely or never forms independent minerals, mostly existing as isomorphous elements within other minerals, making it a typical rare and dispersed element. Due to its high melting point, high density, excellent ductility, formability, and resistance to carburization, rhenium is widely used in aerospace, medical, information, chemical, metallurgical, and defense industries.
[0003] Rhenium is present in very low amounts in the Earth's crust, primarily in molybdenite. However, due to the very similar atomic and ionic radii of rhenium and molybdenum, as well as their similar chemical properties such as their coordination ability, rhenium is extremely difficult to separate from minerals. Therefore, the separation of rhenium and molybdenum is an important research area in separation science and has received widespread attention.
[0004] Research on rhenium separation and purification methods mainly focuses on rhenium-molybdenum separation, including precipitation, ion exchange, and solvent extraction. Among these, solvent extraction is increasingly popular in industry due to its advantages of high separation efficiency, large throughput, low production cost, and high product purity. However, current methods for rhenium separation and purification using solvent extraction present several problems. For example, patent CN101220418B uses TiO2 solid and ultrasonic adsorption at room temperature to separate rhenium-containing solutions. While this method does not use organic solvents, it requires large amounts of acid and alkali to adjust the pH. Patent CN102251107B involves mixing the rhenium-containing raw material with an oxidant under normal pressure and alkaline conditions. After the reaction is complete, the reactants are filtered, and the resulting filtrate is passed through a strongly alkaline solution. After adsorption by the anion exchange resin, the strongly basic anion exchange resin is desorbed, a process requiring a large amount of oxidant. Patent CN118086704A uses molybdenum calcined sand as raw material, leaching molybdenum and rhenium from the calcined sand. While leaching molybdenum, a high-concentration sodium molybdate solution containing rhenium is obtained. Molybdenum and rhenium in the high-concentration sodium molybdate solution are separated through ion exchange adsorption. A special ion exchange desorption process is used to enrich rhenium to obtain a high-concentration ammonium rheniumate solution. This process has high production requirements and is not conducive to industrial application. In summary, existing solvent extraction methods suffer from low extraction efficiency, high extractant costs, and large wastewater discharge, severely limiting their industrial application.
[0005] Therefore, how to provide a rhenium extractant that is efficient, economical, and environmentally friendly has become a technical problem that urgently needs to be solved in this field. Summary of the Invention
[0006] The purpose of this invention is to provide a rhenium extractant and its preparation method, as well as a method for extracting and separating rhenium. The rhenium extractant provided by this invention does not require saponification or activation of the extractant, nor does it require the use of acids, alkalis, or oxidants when used for extracting and separating rhenium. At the same time, the rhenium extraction rate is high and the purity is high. In addition, the rhenium extractant can be reused after back-extraction, which is green and environmentally friendly.
[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution:
[0008] The present invention provides a rhenium extractant comprising, by volume percentage: 5-50% secondary amine, 20-60% diphosphorus oxide, and the balance being a diluent.
[0009] Preferably, the secondary amine has the following structure: The R 1 and R 2 It is independently any one of C1-C20 alkyl, C3-C6 cycloalkyl, and C5-C10 aryl.
[0010] Preferably, the structure of the diphosphorus oxide is as follows: The n is 1 to 20; the R 3 R 4 R 5 and R 6 It is independently any one of C3-C30 alkyl, C3-C8 cycloalkyl, and C5-C20 aryl.
[0011] Preferably, the diluent comprises one or more of kerosene, sulfonated kerosene, n-hexane, cyclohexane, n-octane, isooctane, dichloromethane, dichloroethane, chloroform, carbon tetrachloride, ethyl acetate, dichlorobenzene, trichlorobenzene, octanol, benzene, toluene, and xylene.
[0012] The present invention provides a method for preparing the rhenium extractant described in the above technical solution, comprising: mixing a secondary amine, a diphosphorus oxide and a diluent to obtain the rhenium extractant.
[0013] The present invention also provides a method for extracting and separating rhenium, which involves using a rhenium extractant to perform countercurrent extraction on the extractant, followed by back-extraction to obtain high-purity rhenium salt; wherein the rhenium extractant is the rhenium extractant described in the above technical solution or the rhenium extractant prepared by the preparation method described in the above technical solution.
[0014] Preferably, the volume ratio of the rhenium extractant to the extractant is 1:(1-10).
[0015] Preferably, the number of stages of the countercurrent extraction is 1 to 10; and the temperature of the countercurrent extraction is 10 to 80°C.
[0016] Preferably, the back-extraction agent used in the back-extraction includes one or more of water, ammonium carbonate solution, ammonium bicarbonate solution, ammonia solution, hydroxylamine solution, sodium carbonate solution, and sodium bicarbonate solution.
[0017] Preferably, the number of back-extraction stages is 1 to 5; the back-extraction temperature is 15 to 90°C.
[0018] This invention provides a rhenium extractant, comprising, by volume percentage: 5-50% secondary amine, 20-60% diphosphorus oxide, and the balance diluent. The extractant, composed of secondary amine, diphosphorus oxide, and diluent, exhibits excellent synergistic effects, providing high selectivity for rhenium salts during extraction. This allows for direct extraction of rhenium salts containing other metals without the need for saponification or activation of the extractant, or the use of acids, alkalis, or oxidants. This simplifies and simplifies the extraction process, resulting in high-purity rhenium salt products. Different extractant formulations can be selected for different rhenium-molybdate systems, offering flexibility. Furthermore, both secondary amine and diphosphorus oxide are inexpensive and readily available, resulting in low costs. After back-extraction, the extractant can be reused, making it environmentally friendly and significantly reducing the production and usage costs of rhenium extractants. This enhances the market competitiveness of rhenium extractants and facilitates large-scale industrial application. The results of the examples show that after extracting the mixed solution of sodium perrhenate and sodium molybdate using the rhenium extractant provided by the present invention, the extraction rate of sodium perrhenate is ≥90%, and can reach up to 98%. Sodium perrhenate has high purity and few impurities, with a purity of ≥93%, and can reach up to 99.98%. Detailed Implementation
[0019] The present invention provides a rhenium extractant comprising, by volume percentage: 5-50% secondary amine, 20-60% diphosphorus oxide, and the balance being a diluent.
[0020] The rhenium extractant provided by this invention comprises 5-50% secondary amine by volume percentage. In this invention, the structure of the secondary amine is preferably... The R 1 and R 2 It is preferably any one of C1-C20 alkyl, C3-C6 cycloalkyl and C5-C10 aryl, and more preferably any one of C6-C18 alkyl, C5-C6 cycloalkyl and C5-C8 aryl.
[0021] In one embodiment of the present invention, the volume percentage of the secondary amine may be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50%; the secondary amine may be N-butylcyclohexylamine (CAS: 10108-56-2), dicyclohexylamine (CAS: 101-83-7), di-n-butylamine (CAS: 111-92-2), di-n-octylamine (CAS: 1120-48-5), N-cyclopentylcyclohexylamine (CAS: 40649-25-0), N-cyclopropylmethylcyclohexylamine (CAS: 99175-40-3), 4,4'-dimethyldicyclohexylamine (CAS: 109667-09-6), or diphenylamine (CAS: 122-39-4).
[0022] The rhenium extractant provided by this invention comprises 20-60% diphosphorus oxide by volume percentage. In this invention, the structure of the diphosphorus oxide is preferably... The n is preferably 1 to 20, more preferably 1 to 10; the R 3 R 4 R 5 and R 6 It is preferably any one of C3-C30 alkyl, C3-C8 cycloalkyl and C5-C20 aryl, and more preferably any one of C4-C10 alkyl, C4-C6 cycloalkyl and C5-C10 aryl.
[0023] In one embodiment of the present invention, the volume percentage of the bisphosphonate oxide can be 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, or 60%; the bisphosphonate oxide can be butane-1,4-diylbis(diphenylphosphine oxide) (CAS: 4151-27-3), propane-1,3-diylbis(diphenylphosphine oxide) (CAS: 16524-41-7), or 1,2-bis(diphenylphosphoxy)ethane (CAS: 4141-50-8). 4-Dimethylphosphoxy-1-diphenylphosphoxypropane (CAS: 89807-21-6), 4-diethylphosphoxy-1-diphenylphosphoxypropane (CAS: 89807-22-7), 4-dimethylphosphoxy-1-dimethylphosphoxybutane (CAS: 98543-48-7), 1,6-diphosphoxybicyclo[4.3.3]octane (CAS: 342824-55-9) or dibutyl[4-(butylphenylphosphoxy)butyl]phosphoxy (CAS: 199284-22-5).
[0024] The rhenium extractant provided by this invention, by volume percentage, comprises the balance being a diluent. In this invention, the diluent preferably comprises one or more of kerosene, sulfonated kerosene, n-hexane, cyclohexane, n-octane, isooctane, dichloromethane, dichloroethane, chloroform, carbon tetrachloride, ethyl acetate, dichlorobenzene, trichlorobenzene, octanol, benzene, toluene, and xylene, more preferably one or more of kerosene, sulfonated kerosene, cyclohexane, dichloroethane, chloroform, dichlorobenzene, trichlorobenzene, octanol, toluene, and xylene. In this invention, the diluent primarily provides a liquid environment for the secondary amine and diphosphorus oxides, facilitating subsequent extraction of rhenium salts.
[0025] This invention employs a secondary amine, diphosphorus oxides, and a diluent as the extractant. The secondary amine and diphosphorus oxides exhibit excellent synergistic effects, providing high selectivity for rhenium salts during extraction. This allows for direct extraction of rhenium salts containing other metals without the need for saponification or activation of the extractant, or the use of acids, alkalis, or oxidants. This simplifies and simplifies the extraction process, resulting in high-purity rhenium salt products. Different extractant formulations can be selected for different rhenium-molybdate systems, offering flexibility in extractant selection. Furthermore, both the secondary amine and diphosphorus oxides are inexpensive and readily available, resulting in low costs. After back-extraction, the extractant can be reused, making it environmentally friendly and significantly reducing the production and usage costs of rhenium extractants. This enhances the market competitiveness of rhenium extractants and facilitates large-scale industrial application.
[0026] The present invention also provides a method for preparing the rhenium extractant described in the above technical solution, comprising: mixing a secondary amine, a diphosphorus oxide and a diluent to obtain the rhenium extractant.
[0027] The present invention does not have any special limitations on the specific operation of the mixing, as long as the secondary amine, diphosphorus oxide and diluent are mixed evenly.
[0028] The preparation method provided by this invention is simple, requires no special equipment, and is conducive to its large-scale industrial application.
[0029] The present invention also provides a method for extracting and separating rhenium, which involves using a rhenium extractant to perform countercurrent extraction on the extractant, followed by back-extraction to obtain high-purity rhenium salt; wherein the rhenium extractant is the rhenium extractant described in the above technical solution or the rhenium extractant prepared by the preparation method described in the above technical solution.
[0030] In this invention, the extractant is a mixed solution of rhenium salt and molybdate; the rhenium salt is preferably a soluble rhenium salt, more preferably sodium perrhenate (NaO4Re); the molybdate is preferably a soluble molybdate, more preferably sodium molybdate; the concentration of rhenium in the mixed solution is preferably 5-500 g / L, and the concentration of molybdenum is preferably 0.1-50 g / L.
[0031] In one embodiment of the present invention, the concentration of rhenium in the mixed solution can be 5 g / L, 10 g / L, 20 g / L, 30 g / L, 50 g / L, 80 g / L, 100 g / L, 150 g / L, 200 g / L, 250 g / L, 300 g / L, 350 g / L, 400 g / L, 450 g / L, or 500 g / L; the concentration of molybdenum in the mixed solution can be 0.1 g / L, 1 g / L, 2 g / L, 3 g / L, 5 g / L, 10 g / L, 15 g / L, 20 g / L, 25 g / L, 30 g / L, 35 g / L, 40 g / L, 45 g / L, or 50 g / L.
[0032] In this invention, the volume ratio of the rhenium extractant to the extractant is preferably 1:(1-10), more preferably 1:(1-5). By controlling the concentrations of the rhenium extractant and the extractant, as well as their volume ratio, this invention ensures that the rhenium extractant extracts the rhenium element from the extractant.
[0033] In one embodiment of the present invention, the volume ratio of the rhenium extractant to the extractant can be 1:2, 1:3 or 1:4.
[0034] In this invention, the countercurrent extraction is preferably carried out in a mixing and clarification tank, an extraction tower, or a centrifuge. This invention does not impose any special limitations on the specific model or source of the mixing and clarification tank, extraction tower, or centrifuge; commercially available mixing and clarification tanks, extraction towers, or centrifuges well-known to those skilled in the art can be used.
[0035] In this invention, the number of countercurrent extraction stages is preferably 1 to 10; the temperature of the countercurrent extraction is preferably 10 to 80°C. This invention uses countercurrent extraction to extract rhenium salt solutions, which can improve the rhenium extraction rate; by controlling the number of countercurrent extraction stages and the temperature, the rhenium extraction rate can be further improved.
[0036] In one embodiment of the present invention, the number of stages of the countercurrent extraction can be 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10; the temperature of the countercurrent extraction can be 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, or 80°C; and the time of the countercurrent extraction can be 3 min, 5 min, 8 min, 10 min, 12 min, 15 min, 18 min, or 20 min.
[0037] In this invention, the back-extraction agent used preferably includes one or more of water, ammonium carbonate solution, ammonium bicarbonate solution, ammonia solution, hydroxylamine solution, sodium carbonate solution, and sodium bicarbonate solution. This invention does not impose any particular limitation on the concentration of the ammonium carbonate solution, ammonium bicarbonate solution, ammonia solution, hydroxylamine solution, sodium carbonate solution, and sodium bicarbonate solution; it is determined based on the technical knowledge of those skilled in the art that the concentration is sufficient to back-extract the rhenium salt from the extractant. As one embodiment of this invention, the mass concentration of the ammonium carbonate solution, ammonium bicarbonate solution, ammonia solution, hydroxylamine solution, sodium carbonate solution, and sodium bicarbonate solution can be 5%, 10%, 15%, 20%, 25%, 30%, 35%, or 40%.
[0038] In this invention, the number of back-extraction stages is preferably 1 to 5; the back-extraction temperature is preferably 15 to 90°C. This invention does not have a specific limitation on the back-extraction time; it can be determined based on the technical knowledge of those skilled in the art, as long as it is sufficient to allow the rhenium salt to be back-extracted from the extractant. This invention can improve the back-extraction efficiency by controlling the back-extraction temperature.
[0039] In one embodiment of the present invention, the number of back-extraction stages can be 1, 2, 3, 4, or 5; the back-extraction temperature can be 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, or 90°C; and the back-extraction time can be 1 min, 2 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, or 10 min.
[0040] In this invention, the rhenium extractant after back-extraction is preferably recycled. The rhenium extractant provided by this invention, after back-extraction, contains very few impurities and can be reused for countercurrent extraction of the extractant, thereby reducing production costs.
[0041] The extraction and separation method for rhenium provided by this invention has a simple extraction process with only two steps: extraction and back-extraction. The equipment used is conventional, and the extraction conditions are simple, requiring only room temperature or appropriate heating. The extractant does not require pretreatment such as saponification, which reduces the use of reagents such as acids and alkalis. It has low equipment requirements and is economical.
[0042] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.
[0043] Example 1
[0044] A rhenium extractant, by volume percentage, comprises: 5% secondary amine, 20% diphosphorus oxide, and the balance being a diluent;
[0045] The secondary amine is N-butylcyclohexylamine (CAS: 10108-56-2), the diphosphorus oxide is butane-1,4-dimethylbis(diphenylphosphine oxide) (CAS: 4151-27-3), and the diluent is sulfonated kerosene.
[0046] The rhenium extractant is prepared by mixing secondary amine, diphosphorus oxide and diluent at room temperature and stirring until homogeneous to obtain the rhenium extractant.
[0047] Application Example 1
[0048] A method for extracting and separating rhenium involves countercurrent extraction of the extractant to be extracted in a mixing and clarifying tank using the rhenium extractant of Example 1, followed by back-extraction to obtain high-purity rhenium salt.
[0049] The extraction solution is a mixed solution of sodium perrhenate and sodium molybdate; the concentration of rhenium in the mixed solution is 10 g / L and the concentration of molybdenum is 2 g / L.
[0050] The volume ratio of the rhenium extractant to the extractant is 1:1:
[0051] The countercurrent extraction process consists of three stages, with a temperature of 20°C and a extraction time of 10 minutes.
[0052] The back-extraction agent used is water, the back-extraction stage is 1, the back-extraction temperature is 30℃, the back-extraction time is 3min, and the rhenium extractant after back-extraction is recycled.
[0053] Example 2
[0054] A rhenium extractant, by volume percentage, comprises: 5% secondary amine, 60% diphosphorus oxide, and the balance being a diluent;
[0055] The secondary amine is dicyclohexylamine (CAS: 101-83-7), the diphosphine oxide is propane-1,3-dimethylbis(diphenylphosphine oxide) (CAS: 16524-41-7), and the diluent is xylene;
[0056] The rhenium extractant is prepared by mixing secondary amine, diphosphorus oxide and diluent at room temperature and stirring until homogeneous to obtain the rhenium extractant.
[0057] Application Example 2
[0058] A method for extracting and separating rhenium involves using the rhenium extractant of Example 2 in a centrifugal extractor to perform countercurrent extraction on the extractant, followed by back-extraction to obtain high-purity rhenium salt.
[0059] The extraction solution is a mixed solution of sodium perrhenate and sodium molybdate; the concentration of rhenium in the mixed solution is 30 g / L and the concentration of molybdenum is 3 g / L.
[0060] The volume ratio of the rhenium extractant to the extractant is 2:1:
[0061] The countercurrent extraction process consists of 5 stages, the temperature is 25°C, and the extraction time is 10 min.
[0062] The back-extraction agent used is an ammonium carbonate solution with a mass concentration of 15%. The back-extraction stage is 1 stage, the back-extraction temperature is 35°C, and the back-extraction time is 3 minutes. The rhenium extractant after back-extraction is recycled.
[0063] Example 3
[0064] A rhenium extractant, by volume percentage, comprises: 15% secondary amine, 45% diphosphorus oxide, and the balance being a diluent;
[0065] The secondary amine is di-n-butylamine (CAS: 111-92-2), the diphosphide oxide is 1,2-bis(diphenylphosphoxy)ethane (CAS: 4141-50-8), and the diluent is trichlorobenzene;
[0066] The rhenium extractant is prepared by mixing secondary amine, diphosphorus oxide and diluent at room temperature and stirring until homogeneous to obtain the rhenium extractant.
[0067] Application Example 3
[0068] A method for extracting and separating rhenium involves using the rhenium extractant of Example 3 in a centrifugal extractor to perform countercurrent extraction on the extractant, followed by back-extraction to obtain high-purity rhenium salt.
[0069] The extraction solution is a mixed solution of sodium perrhenate and sodium molybdate; the concentration of rhenium in the mixed solution is 25 g / L and the concentration of molybdenum is 1 g / L.
[0070] The volume ratio of the rhenium extractant to the extractant is 3:1.
[0071] The countercurrent extraction process consists of 4 stages, the temperature is 45°C, and the extraction time is 10 min.
[0072] The back-extraction agent used is ammonia water with a mass concentration of 20%. The back-extraction stage is 1, the back-extraction temperature is 40℃, and the back-extraction time is 2 minutes. The rhenium extractant after back-extraction is recycled.
[0073] Example 4
[0074] A rhenium extractant, by volume percentage, comprises: 20% secondary amine, 35% diphosphorus oxide, and the balance being a diluent;
[0075] The secondary amine is di-n-octylamine (CAS: 1120-48-5), the diphosphorus oxide is 4-dimethylphosphoxy-1-diphenylphosphoxypropane (CAS: 89807-21-6), and the diluent is octanol;
[0076] The rhenium extractant is prepared by mixing secondary amine, diphosphorus oxide and diluent at room temperature and stirring until homogeneous to obtain the rhenium extractant.
[0077] Application Example 4
[0078] A method for extracting and separating rhenium involves using the rhenium extractant of Example 4 in a centrifugal extractor to perform countercurrent extraction on the extractant, followed by back-extraction to obtain high-purity rhenium salt.
[0079] The extraction solution is a mixed solution of sodium perrhenate and sodium molybdate; the concentration of rhenium in the mixed solution is 15 g / L and the concentration of molybdenum is 1 g / L.
[0080] The volume ratio of the rhenium extractant to the extractant is 2:1:
[0081] The countercurrent extraction process consists of three stages, with a temperature of 50°C and a extraction time of 10 minutes.
[0082] The back-extraction agent used is a hydroxylamine solution with a mass concentration of 20%. The back-extraction stage is 1, the back-extraction temperature is 50°C, and the back-extraction time is 1 min. The rhenium extractant after back-extraction is recycled.
[0083] Example 5
[0084] A rhenium extractant, by volume percentage, comprises: 30% secondary amine, 30% diphosphorus oxide, and the balance being a diluent;
[0085] The secondary amine is N-cyclopentylcyclohexylamine (CAS: 40649-25-0), the diphosphorus oxide is 4-diethylphosphoroxo-1-diphenylphosphoroxopropane (CAS: 89807-22-7), and the diluent is n-hexane;
[0086] The rhenium extractant is prepared by mixing secondary amine, diphosphorus oxide and diluent at room temperature and stirring until homogeneous to obtain the rhenium extractant.
[0087] Application Example 5
[0088] A method for extracting and separating rhenium involves using the rhenium extractant of Example 5 in a centrifugal extractor to perform countercurrent extraction on the extractant, followed by back-extraction to obtain high-purity rhenium salt.
[0089] The extraction solution is a mixed solution of sodium perrhenate and sodium molybdate; the concentration of rhenium in the mixed solution is 15 g / L and the concentration of molybdenum is 1 g / L.
[0090] The volume ratio of the rhenium extractant to the extractant is 2:1:
[0091] The countercurrent extraction process consists of three stages, with a temperature of 60°C and a extraction time of 10 minutes.
[0092] The back-extraction agent used is a sodium carbonate solution with a mass concentration of 20%. The back-extraction stage is 1, the back-extraction temperature is 70°C, and the back-extraction time is 1 minute. The rhenium extractant after back-extraction is recycled.
[0093] Example 6
[0094] A rhenium extractant, by volume percentage, comprises: 50% secondary amine, 30% diphosphorus oxide, and the balance being a diluent;
[0095] The secondary amine is N-cyclopropylmethylcyclohexylamine (CAS: 99175-40-3), the diphosphorus oxide is 4-dimethylphosphoxy-1-dimethylphosphoxybutane (CAS: 98543-48-7), and the diluent is chloroform;
[0096] The rhenium extractant is prepared by mixing secondary amine, diphosphorus oxide and diluent at room temperature and stirring until homogeneous to obtain the rhenium extractant.
[0097] Application Example 6
[0098] A method for extracting and separating rhenium involves countercurrent extraction of the extractant to be extracted in an extraction tower using the rhenium extractant of Example 6, followed by back-extraction to obtain high-purity rhenium salt.
[0099] The extraction solution is a mixed solution of sodium perrhenate and sodium molybdate; the concentration of rhenium in the mixed solution is 150 g / L and the concentration of molybdenum is 1 g / L.
[0100] The volume ratio of the rhenium extractant to the extractant is 5:1.
[0101] The countercurrent extraction process consists of three stages, with a temperature of 48°C and a extraction time of 20 minutes.
[0102] The back-extraction agent used is ammonium bicarbonate solution with a mass concentration of 30%. The back-extraction stage is 1, the back-extraction temperature is 50°C, and the back-extraction time is 5 minutes. The rhenium extractant after back-extraction is recycled.
[0103] Example 7
[0104] A rhenium extractant, by volume percentage, comprises: 17% secondary amine, 42% diphosphorus oxide, and the balance being a diluent;
[0105] The secondary amine is 4,4'-dimethyldicyclohexylamine (CAS: 109667-09-6), the diphosphorus oxide is 1,6-diphosphorusoxybicyclo[4.3.3]octane (CAS: 342824-55-9), and the diluent is cyclohexane;
[0106] The rhenium extractant is prepared by mixing secondary amine, diphosphorus oxide and diluent at room temperature and stirring until homogeneous to obtain the rhenium extractant.
[0107] Application Example 7
[0108] A method for extracting and separating rhenium involves countercurrent extraction of the extractant to be extracted in a mixing and clarifying tank using the rhenium extractant of Example 7, followed by back-extraction to obtain high-purity rhenium salt.
[0109] The extraction solution is a mixed solution of sodium perrhenate and sodium molybdate; the concentration of rhenium in the mixed solution is 300 g / L and the concentration of molybdenum is 20 g / L.
[0110] The volume ratio of the rhenium extractant to the extractant is 1:1:
[0111] The countercurrent extraction process consists of 6 stages, with a temperature of 25°C and a extraction time of 15 minutes.
[0112] The back-extraction agent used is a sodium bicarbonate solution with a mass concentration of 20%. The back-extraction process consists of three stages, the back-extraction temperature is 35°C, and the back-extraction time is 3 minutes. The rhenium extractant after back-extraction is recycled.
[0113] Example 8
[0114] A rhenium extractant, by volume percentage, comprises: 40% secondary amine, 40% diphosphorus oxide, and the balance being a diluent;
[0115] The secondary amine is diphenylamine (CAS: 122-39-4), the diphosphorus oxide is dibutyl[4-(butylphenylphosphoxy)butyl]phosphoxy (CAS: 199284-22-5), and the diluent is ethyl acetate;
[0116] The rhenium extractant is prepared by mixing secondary amine, diphosphorus oxide and diluent at room temperature and stirring until homogeneous to obtain the rhenium extractant.
[0117] Application Example 8
[0118] A method for extracting and separating rhenium involves using the rhenium extractant of Example 8 in a centrifugal extractor to perform countercurrent extraction on the extractant, followed by back-extraction to obtain high-purity rhenium salt.
[0119] The extraction solution is a mixed solution of sodium perrhenate and sodium molybdate; the concentration of rhenium in the mixed solution is 200 g / L and the concentration of molybdenum is 17 g / L.
[0120] The volume ratio of the rhenium extractant to the extractant is 2:1:
[0121] The countercurrent extraction process consists of 6 stages, with a temperature of 25°C and a extraction time of 5 minutes.
[0122] The back-extraction agent used is a sodium carbonate solution with a mass concentration of 20%. The back-extraction stage is 2 stages, the back-extraction temperature is 30°C, and the back-extraction time is 1 minute. The rhenium extractant after back-extraction is recycled.
[0123] The extraction rates and purities of sodium perrhenate obtained from Examples 1-8 are shown in Table 1.
[0124] Table 1 shows the extraction rate and purity of sodium perrhenate obtained from Application Examples 1-8.
[0125] Example Sodium perrhenate extraction rate / % Purity of sodium perrhenate / % Application Example 1 90 95 Application Example 2 92 97 Application Example 3 97 99 Application Example 4 98 99.98 Application Example 5 98 99.98 Application Example 6 91 93 Application Example 7 92 96 Application Example 8 97 99
[0126] The purity was determined by using an ICP-MS instrument to measure the content of sodium perrhenate and sodium molybdate in the solution, thus obtaining the purity of sodium perrhenate.
[0127] As shown in Table 1, after extracting a mixed solution of sodium perrhenate and sodium molybdate using the rhenium extractant provided by this invention, the extraction rate of sodium perrhenate is ≥90%, and can reach up to 98%. The purity of sodium perrhenate is high, with few impurities, and the purity is ≥93%, and can reach up to 99.98%. This indicates that the rhenium extractant provided by this invention can be used for the extraction of rhenium and can achieve a very good extraction effect.
[0128] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A rhenium extractant, comprising, by volume percentage: 5-50% secondary amine, 20-60% diphosphorus oxide, and the balance being a diluent; The structure of the secondary amine is as follows: The R 1 and R 2 It is independently any one of C1-C20 alkyl, C3-C6 cycloalkyl, and C5-C10 aryl; The structure of the diphosphide oxide is as follows: The n is 1~20; the R 3 R 4 R 5 and R 6 It is independently any one of C3-C30 alkyl, C3-C8 cycloalkyl and C5-C20 aryl.
2. The rhenium extractant according to claim 1, characterized in that, The diluent includes one or more of the following: kerosene, sulfonated kerosene, n-hexane, cyclohexane, n-octane, isooctane, dichloromethane, dichloroethane, chloroform, carbon tetrachloride, ethyl acetate, dichlorobenzene, trichlorobenzene, octanol, benzene, toluene, and xylene.
3. A method for preparing the rhenium extractant according to any one of claims 1 to 2, comprising: The secondary amine, diphosphorus oxide, and diluent are mixed to obtain the rhenium extractant.
4. A method for extracting and separating rhenium, characterized in that, The extract to be extracted was subjected to countercurrent extraction using a rhenium extractant, followed by back-extraction to obtain high-purity rhenium salt; the rhenium extractant was the rhenium extractant according to any one of claims 1 to 2 or the rhenium extractant prepared by the preparation method according to claim 3.
5. The method according to claim 4, characterized in that, The volume ratio of the rhenium extractant to the extractant is 1:(1~10).
6. The method according to claim 4, characterized in that, The countercurrent extraction has 1 to 10 stages; the temperature of the countercurrent extraction is 10 to 80°C.
7. The method according to claim 4, characterized in that, The back-extraction agent used in the back-extraction includes one or more of water, ammonium carbonate solution, ammonium bicarbonate solution, ammonia solution, hydroxylamine solution, sodium carbonate solution, and sodium bicarbonate solution.
8. The method according to claim 4, characterized in that, The number of back-extraction stages is 1 to 5; the back-extraction temperature is 15 to 90°C.