Method for stripping rhenium from a polymer-rich aqueous phase in an aqueous two-phase extraction

Abstract

This invention relates to a method for stripping rhenium and molybdenum from the polymer-rich aqueous phase during aqueous two-phase extraction, belonging to the field of metal ion separation and recovery in solution. The invention synthesizes a ternary hydrophobic eutectic solvent using oleic acid, trioctylmethylammonium chloride, and diisooctyl phosphate as precursors in appropriate proportions. This solvent is then used to strip rhenium and molybdenum from the polymer aqueous phase after aqueous two-phase extraction. The mass ratio of the ternary hydrophobic eutectic solvent to the rhenium- and molybdenum-rich polymer aqueous phase is 1:2~15. The pH is adjusted to 1~7, and the mixture is stirred at 25~50℃ for 2~30 min, then allowed to stand for 5 min~2 h to separate the phases, obtaining the rhenium- and molybdenum-rich eutectic solvent phase and the polymer aqueous phase. The ternary hydrophobic eutectic solvent designed in this invention has advantages such as simple preparation, environmental friendliness, strong molybdenum and rhenium extraction capability, and wide applicability. It has high stripping efficiency of rhenium and molybdenum ions from the polymer aqueous phase during aqueous two-phase extraction, and simultaneously allows for the recycling of the polymer in the aqueous two-phase system.

Description

Technical Field

[0001] This invention relates to a method for stripping rhenium and molybdenum from the polymer-rich aqueous phase in an aqueous two-phase extraction process, belonging to the field of metal ion separation and recovery in solution. Specifically, it relates to the synthesis of a ternary hydrophobic eutectic solvent for stripping rhenium and molybdenum from the polymer-rich aqueous phase after the separation of rhenium and molybdenum ions in an aqueous two-phase extraction system, thereby realizing the recycling of the polymer in the aqueous two-phase extraction process. Background Technology

[0002] Rhenium is a high-density, high-melting-point transition metal, often found as an association with minerals such as molybdenum and copper, with an abundance of 1 × 10⁻⁶ in the Earth's crust. -9 Molybdenum possesses advantages such as high temperature resistance, wear resistance, good plasticity, and excellent catalytic activity, making it widely used in aerospace, electronics, petrochemicals, and cutting-edge defense fields. With its high melting point, low coefficient of thermal expansion, high electrical conductivity, and high thermal conductivity, molybdenum has broad application prospects in aerospace, nuclear fusion reactors, electronics, advanced medical equipment manufacturing, and high-temperature mold materials. Molybdenite (MoS2) is the most important ore source of molybdenum and also the mineral with the highest rhenium content. In nature, approximately 99% of molybdenum exists in the form of molybdenite. The extraction of molybdenum from molybdenite often results in the production of rhenium and copper as byproducts. Furthermore, due to the significant difference in abundance and strong isomorphism between molybdenum and rhenium, effective separation of molybdenum and rhenium is extremely difficult.

[0003] Aqueous two-phase extraction (APE) is a novel extraction and separation method, distinct from traditional organic solvent extraction. It primarily consists of an aqueous solution of two immiscible polymers or one polymer and one inorganic salt. The formation of an APE system is due to the steric hindrance between the molecules of the two components under specific conditions, preventing them from interpenetrating and thus forming two incompatible aqueous phases. Compared to traditional solvent extraction, APE eliminates the need for diluents and toxic organic solvents, offering advantages such as environmental friendliness, low energy consumption, good biocompatibility, ease of expansion, and high separation efficiency, enabling effective separation of molybdenum and rhenium. Muruchi et al. (ACS Sustainable Chemistry & Engineering, 2019, 7(1): 1778-1785) studied the partition coefficients of rhenium and molybdenum in a polymer-CuSO4-H2O APE system, investigating the effects of polymer type and inorganic additives on the partition coefficients. Under conditions of pH=2 and T=35℃, rhenium and molybdenum partitioned into the polymer-rich phase. Adding tetraethylammonium chloride to the polymer-rich phase facilitated the stripping of Mo. Fan et al. (Separations, 2024, 11(5): 142.) achieved efficient separation of rhenium and molybdenum ions using an aqueous two-phase system of E1006-(NH4)2SO4-H2O. The results showed that under the conditions of 200 g / L E-1006, 200 g / L (NH4)2SO4, pH=7, and T=323.5 K, the rhenium extraction rate was 97.2%, and the rhenium-molybdenum separation coefficient reached 2700. Patent CN118910439B discloses a method for extracting and separating rhenium and molybdenum using an aqueous two-phase system composed of glycerol block polyether, ammonium sulfate, and water.

[0004] In summary, various aqueous two-phase systems are currently used for the separation of molybdenum and rhenium. After extraction separation, molybdenum ions are mainly enriched in the salt-rich phase, while rhenium ions are mainly enriched in the polymer-rich aqueous phase. Since rhenium ions exist primarily as perrhenate ions in aqueous solution, it is difficult to achieve rhenium stripping from the polymer-rich phase by adjusting the pH. Furthermore, the concentration difference between molybdenum and rhenium in molybdenite leaching solutions is significant, resulting in a considerable amount of molybdenum ions remaining in the polymer-rich aqueous phase after aqueous two-phase extraction separation. Currently, research on the stripping of rhenium and molybdenum from the polymer-rich aqueous phase and the recovery of the polymer after aqueous two-phase extraction separation of rhenium and molybdenum is scarce. Summary of the Invention

[0005] To address the current issues of stripping rhenium and molybdenum from the polymer-rich aqueous phase and recovering the polymer after separating rhenium and molybdenum using aqueous two-phase extraction, this invention provides a method for stripping rhenium and molybdenum from the polymer-rich aqueous phase during aqueous two-phase extraction, thereby achieving the stripping of rhenium and molybdenum ions from the polymer-rich aqueous phase during aqueous two-phase extraction and the recycling of the polymer.

[0006] This invention synthesizes a ternary hydrophobic eutectic solvent using oleic acid, trioctylmethylammonium chloride, and diisooctyl phosphate as precursors, and uses it to strip rhenium and molybdenum ions from the aqueous phase of a rhenium-molybdenum two-phase system, thereby enabling the recycling of the polymer.

[0007] This invention discloses a method for stripping rhenium and molybdenum from a rhenium- and molybdenum-rich polymer aqueous phase during a two-phase extraction process, comprising the following steps: adding the ternary hydrophobic eutectic solvent to the rhenium- and molybdenum-rich polymer aqueous phase at a mass ratio of 1:2~15, adjusting the pH to 1~7, stirring and allowing to stand at 25~50°C until phase separation is complete, with the upper phase being the rhenium- and molybdenum-rich eutectic solvent phase and the lower phase being the polymer aqueous phase;

[0008] The aqueous phase of the rhenium-molybdenum-rich polymer contains rhenium-molybdenum, and the polymer is propylene glycol block polyether L35;

[0009] The ternary hydrophobic eutectic solvent is prepared by the following process: 1 part by mass of oleic acid, 0.13 to 13.7 parts by mass of trioctylmethylammonium chloride and 0.11 to 11.4 parts by mass of diisooctyl phosphate are added to a reactor and stirred at a constant temperature of 50 to 70°C for 1 to 3 hours to obtain the ternary hydrophobic eutectic solvent.

[0010] As a preferred method, 1 part by weight of oleic acid, 0.5 to 2 parts by weight of trioctylmethylammonium chloride and 0.2 to 1.5 parts by weight of diisooctyl phosphate are added to a reactor and stirred at a constant temperature of 60 to 70°C for 1 to 2 hours to obtain a ternary hydrophobic eutectic solvent.

[0011] As a further preferred option, 1 part by weight of oleic acid, 0.6 to 1.5 parts by weight of trioctylmethylammonium chloride and 0.3 to 0.7 parts by weight of diisooctyl phosphate are added to a reactor and stirred at a constant temperature of 60 to 70°C for 1 to 2 hours to obtain a ternary hydrophobic eutectic solvent.

[0012] As a further preferred option, 1 part by weight of oleic acid, 1.4 parts by weight of trioctylmethylammonium chloride, and 0.6 parts by weight of diisooctyl phosphate are added to a reactor and stirred at a constant temperature of 60-65°C for 1-2 hours to obtain a ternary hydrophobic eutectic solvent; or

[0013] Add 1 part by weight of oleic acid, 0.7 parts by weight of trioctylmethylammonium chloride, and 0.6 parts by weight of diisooctyl phosphate to a reactor, and stir at a constant temperature of 60-65°C for 1.5-2 hours to obtain a ternary hydrophobic eutectic solvent; or

[0014] Add 1 part by mass of oleic acid, 0.7 parts by mass of trioctylmethylammonium chloride and 0.3 parts by mass of diisooctyl phosphate to a reactor and stir at a constant temperature of 70°C for 1.5 hours to obtain a ternary hydrophobic eutectic solvent.

[0015] In this invention, the rhenium- and molybdenum-rich polymer aqueous phase is obtained through the following process: 1 part by mass of the aqueous two-phase system is added to 1-5 parts by mass of the rhenium- and molybdenum-containing solution to be separated; the pH is adjusted to 5-7, and the mixture is stirred at 20-50°C for 5-20 minutes, then allowed to stand for 5 minutes to 3 hours until phase separation is complete. The upper phase is the rhenium- and molybdenum-rich polymer aqueous phase, and the lower phase is the ammonium sulfate aqueous phase. The aqueous two-phase system consists of propylene glycol block polyether L35, ammonium sulfate, and water, wherein the mass percentage concentration of propylene glycol block polyether L35 is 10-25%, the mass percentage concentration of ammonium sulfate is 5%-30%, and the mass ratio of propylene glycol block polyether L35, ammonium sulfate, and water is 1:(0.2-2):(2-8).

[0016] As a preferred embodiment, the present invention provides a method for stripping rhenium and molybdenum from a rhenium- and molybdenum-rich polymer aqueous phase during a two-phase extraction process. The method involves adding the ternary hydrophobic eutectic solvent to the rhenium- and molybdenum-rich polymer aqueous phase at a mass ratio of 1:5~10. The pH is adjusted to 1~7, and the mixture is stirred and allowed to stand at 25~50°C until phase separation is complete. The upper phase is the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase is the polymer aqueous phase.

[0017] In industrial applications, a ternary hydrophobic eutectic solvent is added to a rhenium- and molybdenum-rich aqueous polymer phase, the pH is adjusted to 1-7, and the mixture is stirred at 25-50°C for 5-20 minutes. After standing for 5 minutes to 3 hours, the phase separation is completed. The upper phase is the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase is the aqueous polymer phase.

[0018] Preferably, the aqueous two-phase system is composed of propylene glycol block polyether L35, ammonium sulfate and water, wherein the mass percentage concentration of propylene glycol block polyether L35 is 18-20% and the mass percentage concentration of ammonium sulfate is 10-20%.

[0019] The rhenium mass percentage concentration in the rhenium-molybdenum separation solution is 0.001%~2%, and the molybdenum mass percentage concentration is 0.01%~5%.

[0020] This invention synthesizes a ternary hydrophobic eutectic solvent using oleic acid, trioctylmethylammonium chloride, and diisooctyl phosphate in appropriate proportions as precursors, and uses it to strip rhenium and molybdenum from the polymer-rich aqueous phase after aqueous two-phase extraction separation. Rhenium ions in solution mainly exist as perrhenate ions (ReO4). - Molybdenum ions exist in the form of MoO2, and their form is pH-regulated. When pH < 1.8, molybdenum ions exist as MoO2. 2+Molybdenum ions exist primarily as molybdenum polyacid anions (H₂Mo₇O₄⁻) when pH 1.8 ≤ pH ≤ 5. 24 4- HMo7O 24 5- Mo7O 24 6- The presence of molybdenum ions, due to their low charge density, imparts strong hydrophobicity; when pH ≥ 7, the molybdenum ion transforms into molybdate ions (MoO4). 2- The increased charge density leads to enhanced hydrophilicity, making it difficult for ReO4 to enter the micelle phase. - Maintaining a low charge density, it preferentially distributes to the polymer-rich aqueous phase through hydrophobic matching effects. The distribution of perrhenate ions in the aqueous two-phase system is achieved through a combination of ether coordination and hydrophobic synergy. The ternary hydrophobic eutectic solvent is synthesized from highly hydrophobic components, exhibiting superior hydrophobicity compared to the polymer in the aqueous two-phase system. Furthermore, the chloride ions in the precursor trioctylmethylammonium chloride undergo ion exchange with perrhenate, molybdate, and molybdate ions in the polymer-rich aqueous phase, while the trioctylmethylammonium cation undergoes ion-pair reactions with these ions, transferring rhenium and molybdate ions from the polymer-rich aqueous phase to the hydrophobic eutectic solvent. Diisooctyl phosphate transfers MoO2 through ion exchange association. 2+ The extract was transferred to a hydrophobic eutectic solvent; the synergistic effect of trioctylmethylammonium chloride and diisooctyl phosphate improved the extraction capacity of rhenium and molybdenum. Oleic acid, as a hydrogen bond donor, promoted the dissolution of trioctylmethylammonium chloride and diisooctyl phosphate, reduced the viscosity of the composition, and decreased the occurrence of emulsification.

[0021] Compared with existing technologies, this invention synthesizes a ternary hydrophobic eutectic solvent for stripping rhenium-molybdenum ions from the aqueous phase of a rhenium-molybdenum-rich polymer after aqueous two-phase extraction, while simultaneously enabling polymer recycling. This ternary hydrophobic eutectic solvent exists as a homogeneous liquid at room temperature and possesses advantages such as simple synthesis, no purification required, excellent rhenium-molybdenum stripping performance, wide applicability, and easy recovery. Compared with traditional extractants, it has lower viscosity, requires no diluent addition, and is more environmentally friendly. Detailed Implementation

[0022] To make the purpose and technical solution of the invention clearer, the invention will be further described in detail below with reference to specific examples. The specific examples described herein are used to explain the invention, but do not limit the invention.

[0023] Example 1

[0024] Add 1 part by mass of oleic acid, 1.4 parts by mass of trioctylmethylammonium chloride and 0.6 parts by mass of diisooctyl phosphate to a reactor, and stir at 60°C for 1 hour until a homogeneous and transparent solution is obtained, thus preparing a ternary hydrophobic eutectic solvent.

[0025] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0026] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0027] The aqueous two-phase system consists of 20% (w / w) propylene glycol block polyether L35 and 10% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.02% (w / w) rhenium and 0.8% (w / w) molybdenum. The pH of the solution was adjusted to 6, and the mixture was stirred at 30°C for 20 min, then allowed to stand for 40 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich polymer aqueous phase, and the lower phase was an ammonium sulfate aqueous phase.

[0028] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0029] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to nine parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase. The pH was adjusted to 1, and the mixture was stirred at 30°C for 10 min and allowed to stand for 30 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase, thereby achieving the stripping of rhenium and molybdenum from the polymer aqueous phase. An appropriate amount of ammonium sulfate was added to the polymer aqueous phase after the stripping of rhenium and molybdenum to reconstitute the aqueous two-phase system (the mass percentage concentration of ammonium sulfate in the reconstituted aqueous two-phase system was 10%) for rhenium- and molybdenum separation. By analyzing and measuring the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 95.82%, and the stripping rate of molybdenum ions was 96.11%.

[0030] Example 2

[0031] Add 1 part by mass of oleic acid, 1.4 parts by mass of trioctylmethylammonium chloride and 0.6 parts by mass of diisooctyl phosphate to a reactor, and stir at 60°C for 2 hours until a homogeneous and transparent solution is obtained, thus preparing a ternary hydrophobic eutectic solvent.

[0032] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0033] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0034] The aqueous two-phase system consisted of 20% (w / w) propylene glycol block polyether L35 and 12% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.03% (w / w) rhenium and 1% (w / w) molybdenum. The pH of the solution was adjusted to 7, and the mixture was stirred at 30°C for 20 min, then allowed to stand for 40 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich aqueous polymer phase, and the lower phase was an ammonium sulfate aqueous phase.

[0035] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0036] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to six parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase. The pH was adjusted to 2, and the mixture was stirred at 35°C for 15 min and allowed to stand for 30 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase, thereby achieving the stripping of rhenium and molybdenum from the polymer aqueous phase. An appropriate amount of ammonium sulfate was added to the polymer aqueous phase after the stripping of rhenium and molybdenum to reconstitute the aqueous two-phase system (the mass percentage concentration of ammonium sulfate in the reconstituted aqueous two-phase system was 12%) for rhenium- and molybdenum separation. By analyzing and measuring the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 97.79%, and the stripping rate of molybdenum ions was 98.26%.

[0037] Example 3

[0038] Add 1 part by mass of oleic acid, 0.7 parts by mass of trioctylmethylammonium chloride and 0.6 parts by mass of diisooctyl phosphate to a reactor, and stir at 65°C for 2 hours until a homogeneous and transparent solution is obtained, thus preparing a ternary hydrophobic eutectic solvent.

[0039] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0040] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0041] The aqueous two-phase system consisted of 20% (w / w) propylene glycol block polyether L35 and 14% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.02% (w / w) rhenium and 0.8% (w / w) molybdenum. The pH of the solution was adjusted to 6.5, and the mixture was stirred at 30°C for 20 min, then allowed to stand for 30 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich aqueous polymer phase, and the lower phase was an ammonium sulfate aqueous phase.

[0042] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0043] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to six parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase. The pH was adjusted to 2, and the mixture was stirred at 35°C for 20 min and allowed to stand for 35 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase, thereby achieving the stripping of rhenium and molybdenum from the polymer aqueous phase. An appropriate amount of ammonium sulfate was added to the polymer aqueous phase after the stripping of rhenium and molybdenum to reconstitute the aqueous two-phase system (the mass percentage concentration of ammonium sulfate in the reconstituted aqueous two-phase system was 14%) for rhenium- and molybdenum separation. By analyzing and measuring the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 97.35%, and the stripping rate of molybdenum ions was 98.64%.

[0044] Example 4

[0045] Add 1 part by mass of oleic acid, 0.7 parts by mass of trioctylmethylammonium chloride and 0.6 parts by mass of diisooctyl phosphate to a reactor, and stir at 60°C for 1.5 h until a homogeneous and transparent solution is obtained, thus preparing a ternary hydrophobic eutectic solvent.

[0046] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0047] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0048] The aqueous two-phase system consists of 18% (w / w) propylene glycol block polyether L35 and 10% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.04% (w / w) rhenium and 1.2% (w / w) molybdenum. The pH of the solution was adjusted to 7, and the mixture was stirred at 40°C for 15 min, then allowed to stand for 40 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich polymer aqueous phase, and the lower phase was an ammonium sulfate aqueous phase.

[0049] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0050] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to nine parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase. The pH was adjusted to 2, and the mixture was stirred at 30°C for 8 minutes and allowed to stand for 25 minutes until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase, thereby achieving the stripping of rhenium and molybdenum from the polymer aqueous phase. An appropriate amount of ammonium sulfate was added to the polymer aqueous phase after the stripping of rhenium and molybdenum to reconstitute the aqueous two-phase system (the mass percentage concentration of ammonium sulfate in the reconstituted aqueous two-phase system was 10%) for rhenium- and molybdenum separation. By analyzing and measuring the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 93.74%, and the stripping rate of molybdenum ions was 95.14%.

[0051] Example 5

[0052] Add 1 part by mass of oleic acid, 0.7 parts by mass of trioctylmethylammonium chloride and 0.3 parts by mass of diisooctyl phosphate to a reactor, and stir at 70°C for 1.5 h until a homogeneous and transparent solution is formed, thus obtaining a ternary hydrophobic eutectic solvent.

[0053] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0054] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0055] The aqueous two-phase system consists of 20% (w / w) propylene glycol block polyether L35 and 20% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.02% (w / w) rhenium and 0.8% (w / w) molybdenum. The pH of the solution was adjusted to 6, and the mixture was stirred at 25°C for 20 min, then allowed to stand for 45 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich aqueous polymer phase, and the lower phase was an ammonium sulfate aqueous phase.

[0056] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0057] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to six parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase. The pH was adjusted to 4, and the mixture was stirred at 30°C for 12 min and allowed to stand for 35 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase, thereby achieving the stripping of rhenium and molybdenum from the polymer aqueous phase. An appropriate amount of ammonium sulfate was added to the polymer aqueous phase after the stripping of rhenium and molybdenum to reconstitute the aqueous two-phase system (the mass percentage concentration of ammonium sulfate in the reconstituted aqueous two-phase system was 20%) for rhenium- and molybdenum separation. By analyzing and measuring the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 95.56%, and the stripping rate of molybdenum ions was 93.28%.

[0058] Example 6

[0059] Add 1 part by mass of oleic acid, 1.4 parts by mass of trioctylmethylammonium chloride and 0.6 parts by mass of diisooctyl phosphate to a reactor, and stir at 60°C for 2 hours until a homogeneous and transparent solution is obtained, thus preparing a ternary hydrophobic eutectic solvent.

[0060] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0061] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0062] The aqueous two-phase system consisted of 20% (w / w) propylene glycol block polyether L35 and 12% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.016% (w / w) rhenium and 0.6% (w / w) molybdenum. The pH of the solution was adjusted to 7, and the mixture was stirred at 25°C for 20 min, then allowed to stand for 1 h until phase separation was complete. The upper phase was a rhenium-molybdenum-rich polymer aqueous phase, and the lower phase was an ammonium sulfate aqueous phase.

[0063] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0064] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to four parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase. The pH was adjusted to 5, and the mixture was stirred at 30°C for 20 min. After standing for 15 min, the phase separation was completed. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase, thereby achieving the stripping of rhenium and molybdenum from the polymer aqueous phase. An appropriate amount of ammonium sulfate was added to the polymer aqueous phase after the stripping of rhenium and molybdenum to reconstitute the aqueous two-phase system (the mass percentage concentration of ammonium sulfate in the reconstituted aqueous two-phase system was 12%) for rhenium- and molybdenum separation. By analyzing and measuring the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 99.55%, and the stripping rate of molybdenum ions was 99.68%.

[0065] Example 7

[0066] Add 1 part by mass of oleic acid, 1.4 parts by mass of trioctylmethylammonium chloride and 0.6 parts by mass of diisooctyl phosphate to a reactor, and stir at 65°C for 1 hour until a homogeneous and transparent solution is obtained, thus preparing a ternary hydrophobic eutectic solvent.

[0067] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0068] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0069] The aqueous two-phase system consists of 18% (w / w) propylene glycol block polyether L35 and 10% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.02% (w / w) rhenium and 0.8% (w / w) molybdenum. The pH of the solution was adjusted to 7, and the mixture was stirred at 25°C for 20 min, then allowed to stand for 1 h until phase separation was complete. The upper phase was a rhenium-molybdenum-rich aqueous polymer phase, and the lower phase was an ammonium sulfate aqueous phase.

[0070] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0071] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to six parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase. The pH was adjusted to 7, and the mixture was stirred at 30°C for 20 min and allowed to stand for 55 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase, thereby achieving the stripping of rhenium and molybdenum from the polymer aqueous phase. An appropriate amount of ammonium sulfate was added to the polymer aqueous phase after the stripping of rhenium and molybdenum to reconstitute the aqueous two-phase system (the mass percentage concentration of ammonium sulfate in the reconstituted aqueous two-phase system was 10%) for rhenium- and molybdenum separation. By analyzing and measuring the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 96.89%, and the stripping rate of molybdenum ions was 97.44%.

[0072] Comparative Example 1

[0073] Add 1 part by weight of oleic acid and 1.4 parts by weight of trioctylmethylammonium chloride to a reactor, and stir at 70°C for 2 hours until a homogeneous and transparent solution is obtained, thus preparing a binary hydrophobic eutectic solvent.

[0074] Using the synthesized binary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0075] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0076] The aqueous two-phase system consists of 20% (w / w) propylene glycol block polyether L35 and 10% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.02% (w / w) rhenium and 0.8% (w / w) molybdenum. The pH of the solution was adjusted to 6, and the mixture was stirred at 30°C for 20 min, then allowed to stand for 40 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich polymer aqueous phase, and the lower phase was an ammonium sulfate aqueous phase.

[0077] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0078] One part by mass of the above-mentioned binary hydrophobic eutectic solvent was added to nine parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase; the pH was adjusted to 1, and the mixture was stirred at 30°C for 10 min, and allowed to stand for 30 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase. By analyzing and determining the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 93.86%, and the stripping rate of molybdenum ions was 85.45%.

[0079] Comparative Example 2

[0080] Add 1 part by mass of oleic acid and 0.6 parts by mass of diisooctyl phosphate to a reactor, and stir at 70°C for 2 hours until a homogeneous and transparent solution is obtained, thus preparing a binary hydrophobic eutectic solvent.

[0081] Using the synthesized binary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0082] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0083] The aqueous two-phase system consists of 20% (w / w) propylene glycol block polyether L35 and 10% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.02% (w / w) rhenium and 0.8% (w / w) molybdenum. The pH of the solution was adjusted to 6, and the mixture was stirred at 30°C for 20 min, then allowed to stand for 40 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich polymer aqueous phase, and the lower phase was an ammonium sulfate aqueous phase.

[0084] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0085] One part by mass of the above-mentioned binary hydrophobic eutectic solvent was added to nine parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase; the pH was adjusted to 1, and the mixture was stirred at 30°C for 10 min, and allowed to stand for 30 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase. By analyzing and determining the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 5.46%, and the stripping rate of molybdenum ions was 83.15%.

[0086] Comparative Example 3

[0087] One part by mass of oleic acid, two parts by mass of trioctylmethylammonium chloride and 0.1 parts by mass of diisooctyl phosphate were added to a reactor and stirred at a constant temperature of 70°C for 1 hour to obtain a ternary hydrophobic eutectic solvent.

[0088] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0089] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0090] The aqueous two-phase system consists of 20% (w / w) propylene glycol block polyether L35 and 10% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.02% (w / w) rhenium and 0.8% (w / w) molybdenum. The pH of the solution was adjusted to 6, and the mixture was stirred at 30°C for 20 min, then allowed to stand for 40 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich polymer aqueous phase, and the lower phase was an ammonium sulfate aqueous phase.

[0091] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0092] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to nine parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase; the pH was adjusted to 1, and the mixture was stirred at 30°C for 10 min, and allowed to stand for 30 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase. By analyzing and determining the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 97.46%, and the stripping rate of molybdenum ions was 90.39%.

[0093] Comparative Example 4

[0094] Add 1 part by mass of oleic acid, 0.1 part by mass of trioctylmethylammonium chloride and 2 parts by mass of diisooctyl phosphate to a reactor and stir at a constant temperature of 70°C for 1 hour to obtain a ternary hydrophobic eutectic solvent.

[0095] Using the synthesized ternary hydrophobic eutectic solvent as an extractant to strip rhenium and molybdenum from the polymer-rich aqueous phase in a two-phase extraction, the process includes the following steps:

[0096] (1) Aqueous two-phase extraction separation of rhenium and molybdenum

[0097] The aqueous two-phase system consists of 20% (w / w) propylene glycol block polyether L35 and 10% (w / w) ammonium sulfate, with the remainder being water. One part (w / w) of the above aqueous two-phase system was added to one part (w / w) of a rhenium-molybdenum separation solution, which consisted of 0.02% (w / w) rhenium and 0.8% (w / w) molybdenum. The pH of the solution was adjusted to 6, and the mixture was stirred at 30°C for 20 min, then allowed to stand for 40 min until phase separation was complete. The upper phase was a rhenium-molybdenum-rich polymer aqueous phase, and the lower phase was an ammonium sulfate aqueous phase.

[0098] (2) Stripping of rhenium and molybdenum in the aqueous phase of the polymer

[0099] One part by mass of the above-mentioned ternary hydrophobic eutectic solvent was added to nine parts by mass of the above-mentioned rhenium- and molybdenum-rich polymer aqueous phase; the pH was adjusted to 1, and the mixture was stirred at 30°C for 10 min, and allowed to stand for 30 min until phase separation was complete. The upper phase was the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase was the polymer aqueous phase. By analyzing and determining the concentrations of rhenium and molybdenum ions, the stripping rate of rhenium ions was calculated to be 47.37%, and the stripping rate of molybdenum ions was 95.64%.

[0100] The above description is only a partial embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for stripping rhenium and molybdenum from a polymer-rich aqueous phase in a two-phase aqueous extraction process, characterized in that, The process includes the following steps: by mass ratio, the ternary hydrophobic eutectic solvent and the rhenium-molybdenum-rich polymer aqueous phase are 1:2~15. The ternary hydrophobic eutectic solvent is added to the rhenium-molybdenum-rich polymer aqueous phase, the pH is adjusted to 1~7, and the mixture is stirred and allowed to stand at 25~50℃ until phase separation is complete. The upper phase is the rhenium-molybdenum-rich eutectic solvent phase, and the lower phase is the polymer aqueous phase. The aqueous phase of the rhenium-molybdenum-rich polymer contains rhenium-molybdenum, and the polymer is propylene glycol block polyether L35; The ternary hydrophobic eutectic solvent is prepared by the following process: 1 part by mass of oleic acid, 0.5 to 2 parts by mass of trioctylmethylammonium chloride and 0.2 to 1.5 parts by mass of diisooctyl phosphate are added to a reactor and stirred at a constant temperature of 60 to 70°C for 1 to 2 hours to obtain the ternary hydrophobic eutectic solvent.

2. The method for stripping rhenium and molybdenum from a polymer-rich aqueous phase in a two-phase extraction process according to claim 1, characterized in that: Add 1 part by weight of oleic acid, 0.6 to 1.5 parts by weight of trioctylmethylammonium chloride and 0.3 to 0.7 parts by weight of diisooctyl phosphate to a reactor and stir at a constant temperature of 60 to 70°C for 1 to 2 hours to obtain a ternary hydrophobic eutectic solvent.

3. The method for stripping rhenium and molybdenum from a polymer-rich aqueous phase in a two-phase extraction process according to claim 1, characterized in that: Add 1 part by weight of oleic acid, 1.4 parts by weight of trioctylmethylammonium chloride, and 0.6 parts by weight of diisooctyl phosphate to a reactor, and stir at a constant temperature of 60-65℃ for 1-2 hours to obtain a ternary hydrophobic eutectic solvent; or Add 1 part by weight of oleic acid, 0.7 parts by weight of trioctylmethylammonium chloride, and 0.6 parts by weight of diisooctyl phosphate to a reactor, and stir at a constant temperature of 60-65°C for 1.5-2 hours to obtain a ternary hydrophobic eutectic solvent; or Add 1 part by mass of oleic acid, 0.7 parts by mass of trioctylmethylammonium chloride and 0.3 parts by mass of diisooctyl phosphate to a reactor and stir at a constant temperature of 70°C for 1.5 hours to obtain a ternary hydrophobic eutectic solvent.

4. The method for stripping rhenium and molybdenum from a polymer-rich aqueous phase in a two-phase extraction process according to claim 1, characterized in that: The rhenium- and molybdenum-rich polymer aqueous phase is obtained through the following process: 1 part by mass of the aqueous two-phase system is added to 1-5 parts by mass of the rhenium- and molybdenum-containing solution to be separated; the pH is adjusted to 5-7, and the mixture is stirred at 20-50°C for 5-20 minutes, then allowed to stand for 5 minutes to 3 hours until phase separation is complete. The upper phase is the rhenium- and molybdenum-rich polymer aqueous phase, and the lower phase is the ammonium sulfate aqueous phase. The aqueous two-phase system consists of propylene glycol block polyether L35, ammonium sulfate, and water, wherein the mass percentage concentration of propylene glycol block polyether L35 is 10-25%, the mass percentage concentration of ammonium sulfate is 5%-30%, and the mass ratio of propylene glycol block polyether L35, ammonium sulfate, and water is 1:(0.2-2):(2-8).

5. The method for stripping rhenium and molybdenum from a polymer-rich aqueous phase in a two-phase extraction process according to claim 1, characterized in that: The ratio of ternary hydrophobic eutectic solvent to rhenium- and molybdenum-rich polymer aqueous phase is 1:5~10 by mass. The ternary hydrophobic eutectic solvent is added to the rhenium- and molybdenum-rich polymer aqueous phase, the pH is adjusted to 1~7, and the mixture is stirred and allowed to stand at 25~50℃ until phase separation is complete. The upper phase is the rhenium- and molybdenum-rich eutectic solvent phase, and the lower phase is the polymer aqueous phase.

6. The method for stripping rhenium and molybdenum from a polymer-rich aqueous phase in a two-phase extraction process according to claim 4, characterized in that: The aqueous two-phase system consists of propylene glycol block polyether L35, ammonium sulfate and water, wherein the mass percentage concentration of propylene glycol block polyether L35 is 18-20% and the mass percentage concentration of ammonium sulfate is 10-20%.

7. The method for stripping rhenium and molybdenum from a polymer-rich aqueous phase in a two-phase extraction process according to claim 4, characterized in that: The rhenium mass percentage concentration in the rhenium-molybdenum separation solution is 0.001%~2%, and the molybdenum mass percentage concentration is 0.01%~5%.