Method for extracting and separating vanadium from vanadium-arsenic solution by using hydrophobic eutectic solvent

Abstract

The present application relates to the technical field of non-ferrous metallurgy. Disclosed is a method for extracting and separating vanadium from a vanadium-arsenic solution by using a hydrophobic eutectic solvent. The method comprises the following steps: S100, the preparation of a hydrophobic eutectic solvent: mixing a hydrogen bond acceptor and a hydrogen bond donor for reaction to form a hydrogen bond network, wherein the hydrogen bond acceptor comprises tetrabutyl ammonium chloride or tetrabutyl ammonium bromide, and the hydrogen bond donor comprises n-octanol, n-nonanol, or n-decanol; and S200, the extraction and separation of vanadium: mixing the hydrophobic eutectic solvent with a vanadium-arsenic solution, oscillating the mixture and then leaving same to stand for phase separation, and performing reverse extraction after phase separation. The method of the present application can be applied to the accurate separation of vanadium from arsenic, tungsten and other impurities in vanadium crystals; by using the hydrophobic eutectic solvent, the pH value of the solution does not need to be deliberately adjusted during the extraction and separation process of vanadium and arsenic; and operation is easy, and the method has good economy and high safety, such that the method can greatly reduce the safety risk during the extraction process, and has good application prospects in the extraction and separation of vanadium and arsenic.

Description

Method for extracting and separating vanadium from vanadium-arsenic solution using a hydrophobic deep eutectic solvent Technical Field

[0001] The present application relates to the technical field of nonferrous metallurgy, and in particular to a method for extracting and separating vanadium from a vanadium-arsenic solution by utilizing a hydrophobic low eutectic solvent. Background Art

[0002] In coal-fired power plants, the denitrification SCR catalyst used for denitrification gradually decreases in denitrification activity as the operating time increases due to poisoning of active components, aging, and other reasons. At present, the waste SCR catalyst mainly uses an alkali leaching-step precipitation process to separate elements such as vanadium, arsenic, silicon, and phosphorus from the TiO2 carrier, and then uses the different solubility of each element under different temperature and alkali concentration conditions to achieve step separation. Application No. CN202110213239.7 discloses a method and application for separating vanadium, tungsten, and arsenic from sodium hydroxide waste liquid. By evaporating and concentrating the sodium hydroxide waste liquid and cooling and crystallizing it, vanadate ions, tungstate ions, and arsenate ions are crystallized to obtain alkali-treated crystals (i.e., vanadium crystals). The vanadium crystals are then dissolved and the concentration of sodium hydroxide in the system is adjusted and two causticization reactions are performed. According to the different solubility under different alkali concentrations, gradient precipitation of each element is formed. After obtaining the vanadium crystals, multiple causticization reactions are required to achieve the separation of vanadium, tungsten, and arsenic. The operation steps are cumbersome and the alkali concentration in the system needs to be adjusted multiple times, which increases the production process cost.

[0003] Extraction is a commonly used method for separating similar ions or ionic groups, but traditional extraction methods are quite different from the concept of environmentally friendly production due to the high cost, high volatility and poor safety of their extractants. The development of new, efficient and green extractants has attracted widespread attention. Ionic liquids are a new type of extractant with low vapor pressure and high stability, but they have the disadvantages of high preparation cost and poor degradability. Low eutectic solvents have similar properties to ionic liquids, with the advantages of extremely low vapor pressure, good thermal stability and chemical stability. Low-temperature eutectic solvents are simple to prepare and have good biodegradability, and have attracted widespread attention from researchers. At present, there is still a lack of a specific extraction and separation method that can be applied to the precise separation of vanadium, arsenic and tungsten in the purification process of vanadium crystals after alkali treatment of spent SCR catalysts.

[0004] Summary of the Invention

[0005] In view of this, the present application provides a method for extracting and separating vanadium from a vanadium-arsenic solution using a hydrophobic low eutectic solvent. The hydrophobic low eutectic solvent can be used for the precise separation of vanadium, arsenic and tungsten in vanadium crystals. At the same time, the extraction and separation process of the present application does not require adjusting the pH value of the solution. After mixing the hydrophobic low eutectic solvent and the vanadium-arsenic solution, the vanadium-arsenic solution system to be extracted can be adjusted to an appropriate range.

[0006] In a first aspect, the present application provides a method for extracting and separating vanadium from a vanadium-arsenic solution using a hydrophobic deep eutectic solvent, the method comprising the following steps: S100, preparation of a hydrophobic deep eutectic solvent: mixing a hydrogen bond acceptor and a hydrogen bond donor and reacting them to form a hydrogen bond network, the hydrogen bond acceptor comprising tetrabutylammonium chloride or tetrabutylammonium bromide, and the hydrogen bond donor comprising any one of n-octanol, n-nonanol, or n-decanol. S200, extraction and separation of vanadium: mixing the hydrophobic deep eutectic solvent with a vanadium-arsenic solution, shaking, standing for phase separation, and stripping after phase separation. The present application first provides a hydrophobic deep eutectic solvent suitable for the precise separation of vanadium, arsenic, and tungsten in vanadium crystals. The hydrogen bond network formed by the hydrophobic deep eutectic solvent can effectively extract vanadium ions from the vanadium-arsenic solution and has low responsiveness to other ions. Secondly, the present application uses a stripping agent NaCl solution to effectively extract vanadium ions from the vanadium-arsenic solution. The vanadium-arsenic solution is a vanadium crystal dissolution solution, and the vanadium single-stage extraction rate is high. Preferably, the hydrogen bond acceptor comprises tetrabutylammonium bromide, and the hydrogen bond donor comprises n-octanol.

[0007] In some embodiments, in step S100, the reaction temperature is 65° C. to 85° C., the reaction time is 3 to 5 hours, and the stirring speed is 100 to 200 RPM. Preferably, the reaction temperature is 70 to 80° C., the reaction time is 4 to 5 hours, and the stirring speed is 180 to 200 RPM. When the reaction conditions of the specific hydrogen bond acceptor and the specific hydrogen bond donor are within the above ranges, the generated hydrogen bond network is more conducive to the extraction of vanadium ions from the vanadium-arsenic solution and has a low response to other ions.

[0008] In some embodiments, in step S100, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:(1-1.4). Preferably, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:1.2.

[0009] In some embodiments, the viscosity of the hydrophobic deep eutectic solvent is 110 cP to 180 cP. Preferably, the viscosity of the hydrophobic deep eutectic solvent is 115 cP to 130 cP. The appropriate viscosity of the hydrophobic deep eutectic solvent facilitates droplet dispersion and mass transfer during oscillation after mixing with the vanadium-arsenic solution, as well as phase separation after extraction, further improving the single-stage extraction rate of vanadium.

[0010] In some embodiments, mixing the hydrophobic deep eutectic solvent with the vanadium-arsenic solution comprises: mixing the hydrophobic deep eutectic solvent and the vanadium-arsenic solution in a volume ratio of 1:(1-2). Preferably, the hydrophobic deep eutectic solvent and the vanadium-arsenic solution are mixed in a volume ratio of 1:1.

[0011] In some embodiments, the concentration of vanadium ions in the vanadium-arsenic solution is 9 g / L to 12 g / L, the concentration of arsenic ions is 8 g / L to 8.5 g / L, and the vanadium-arsenic solution further includes 0.3 g / L to 0.4 g / L of tungsten ions, 0.08 g / L to 1 g / L of silicon ions, and 0.4 g / L to 0.6 g / L of phosphorus ions.

[0012] In some embodiments, in step S200, the oscillating includes oscillating at 40° C. to 60° C. for 8 to 12 minutes, and the standing time for phase separation is 30 to 50 minutes.

[0013] In some embodiments, the oscillation has an oscillation amplitude of 38 mm to 42 mm and a rotation frequency of 280 RPM to 320 RPM.

[0014] In some embodiments, in step S200, the back extraction after phase separation includes: after phase separation, obtaining a vanadium-loaded hydrophobic deep eutectic solvent (loaded organic phase), mixing a back extraction agent and a vanadium-loaded hydrophobic deep eutectic solvent in a volume ratio of (3 to 5): 1, and oscillating and back extraction for 5 to 10 minutes, wherein the concentration of the back extraction agent NaCl solution is 1.5 mol / L to 2 mol / L.

[0015] The beneficial effects brought about by the technical solutions provided in some embodiments of the present application include at least: the hydrogen bond network formed by the hydrophobic deep eutectic solvent described in the present application can effectively extract vanadium ions in the vanadium-arsenic solution, and the extraction rate of other ions is low. The method described in the present application can be applied to the precise separation of vanadium from impurity ions such as arsenic and tungsten in vanadium crystals. The use of the hydrophobic deep eutectic solvent described in the present application does not require deliberate adjustment of the pH value of the solution during the extraction and separation of vanadium and arsenic. The operation is simple, the economy is good, the safety is high, and the safety risks of the extraction process can be greatly reduced. The method has good application prospects in the extraction and separation of vanadium and arsenic. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the following embodiments and comparative examples. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0017] A deep eutectic solvent is a two- or three-component eutectic mixture composed of a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA) in a specific stoichiometric ratio. Due to the extensive hydrogen bond network within the deep eutectic solvent, its viscosity at room temperature is dozens of times greater than that of water. Increasing the temperature or the content of the hydrogen bond donor can effectively reduce the viscosity of the deep eutectic solvent. Currently, there is a lack of a deep eutectic solvent specifically designed for the precise separation of vanadium and arsenic during vanadium crystal purification, as well as a corresponding extraction separation method.

[0018] A method for extracting and separating vanadium from a vanadium-arsenic solution using a hydrophobic deep eutectic solvent comprises the following steps:

[0019] S100. Preparation of a hydrophobic deep eutectic solvent: mixing a hydrogen bond acceptor and a hydrogen bond donor and reacting them to form a hydrogen bond network, wherein the hydrogen bond acceptor comprises tetrabutylammonium chloride or tetrabutylammonium bromide, and the hydrogen bond donor comprises n-octanol, n-nonanol, or n-decanol. S200. Extraction and separation of vanadium: mixing the hydrophobic deep eutectic solvent with a vanadium-arsenic solution, extracting by oscillation, allowing to stand for phase separation, and performing back extraction after phase separation.

[0020] In some embodiments, the hydrogen bond acceptor comprises tetrabutylammonium bromide and the hydrogen bond donor comprises n-octanol.

[0021] In some embodiments, in step S100, the reaction temperature is 65° C. to 85° C., the reaction time is 3 h to 5 h, and the stirring speed is 100 RPM to 200 RPM.

[0022] Illustratively, the reaction temperature of the reaction is 65°C, 70°C, 75°C, 80°C, 85°C, or a range consisting of any two of the above values.

[0023] Illustratively, the reaction time is 3 h, 3.5 h, 4 h, 4.5 h, 5 h, or a range consisting of any two of the above values.

[0024] Illustratively, the stirring speed of the reaction is 100 RPM, 120 RPM, 140 RPM, 150 RPM, 160 RPM, 180 RPM, 200 RPM, or a range consisting of any two of the above values.

[0025] In some embodiments, in step S100, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:(1-1.4).

[0026] Illustratively, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:1, 1:1.2, 1:1.3, 1:1.4, or a range consisting of any two of the above values.

[0027] In some embodiments, the viscosity of the hydrophobic deep eutectic solvent is 110 cP to 180 cP.

[0028] Illustratively, the viscosity of the hydrophobic deep eutectic solvent is 110 cP, 115 cP, 120 cP, 125 cP, 130 cP, 135 cP, 150 cP, 160 cP, 180 cP, or a range consisting of any two of the above values.

[0029] In some embodiments, mixing the hydrophobic deep eutectic solvent with the vanadium-arsenic solution comprises: mixing the hydrophobic deep eutectic solvent with the vanadium-arsenic solution in a volume ratio of 1:(1-2).

[0030] Illustratively, the volume ratio of the hydrophobic deep eutectic solvent to the vanadium arsenic solution is 1:1, 1:1.2, 1:1.4, 1:1.5, 1:1.6, 1:1.8, 1:2, or a range consisting of any two of the above values.

[0031] In some embodiments, the vanadium arsenic solution has a vanadium ion concentration of 9 g / L to 12 g / L, an arsenic ion concentration of 8 g / L to 8.5 g / L, and the vanadium arsenic solution further includes tungsten ions of 0.3 g / L to 0.4 g / L, silicon ions of 0.08 g / L to 1 g / L, and phosphorus ions of 0.4 g / L to 0.6 g / L.

[0032] In some embodiments, in step S200, the oscillation includes oscillating at 40°C to 60°C for 8 to 12 minutes, and the standing time for phase separation is 30 to 50 minutes.

[0033] In some embodiments, the oscillation has an amplitude of 38 mm to 42 mm and a rotation frequency of 280 RPM to 320 RPM.

[0034] In some embodiments, in step S200, the back-extraction after phase separation includes: mixing a back-extraction agent and a hydrophobic deep eutectic solvent loaded with vanadium in a volume ratio of (3 to 5):1, and oscillating and back-extracting for 5 to 10 minutes, wherein the concentration of the back-extraction agent NaCl solution is 1.5 mol / L to 2 mol / L.

[0035] Unless otherwise specified, the reagents used in the following examples can be purchased from conventional biochemical reagent stores. Unless otherwise specified, the methods in the following examples are conventional methods in the art.

[0036] The vanadium crystals were dissolved to obtain a vanadium crystal solution having a pH value of 13. The following examples and comparative examples use the vanadium crystal solution (i.e., vanadium-arsenic solution) as the research object. The contents of the main elements are shown in Table 1:

[0037] Table 1

[0038] Example 1

[0039] Tetrabutylammonium chloride was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution at a ratio of 1:1. The mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes, and then allowed to stand for 30 minutes for phase separation to obtain a loaded organic phase. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution at a ratio of 4:1, and oscillated for stripping for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0040] Example 2

[0041] Tetrabutylammonium chloride was used as a hydrogen bond acceptor, n-nonanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1, and the mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes. After standing for 30 minutes, phase separation was obtained to obtain a loaded organic phase. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1, and oscillated and stripped for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0042] Example 3

[0043] Tetrabutylammonium chloride was used as a hydrogen bond acceptor, n-decanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1, and the mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes. After standing for 30 minutes for phase separation, a loaded organic phase was obtained. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1, and oscillated and stripped for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0044] Example 4

[0045] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1, and the mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes. After standing for 30 minutes for phase separation, a loaded organic phase was obtained. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1, and oscillated and stripped for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0046] Example 5

[0047] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-nonanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution at a ratio of 1:1, and the mixture was shaken at an ambient temperature of 50°C, a swing amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes. After standing for 30 minutes, the phases were separated to obtain a loaded organic phase. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution at a ratio of 4:1, and oscillated and stripped for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0048] Example 6

[0049] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-decanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1, and the mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes. After standing for 30 minutes, phase separation was obtained to obtain a loaded organic phase. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1, and oscillated and stripped for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0050] Example 7

[0051] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1, and the reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution at a ratio of 1:1, and the mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes. After standing for 30 minutes for phase separation, a loaded organic phase was obtained. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution at a ratio of 4:1, and oscillated and stripped for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0052] Example 8

[0053] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.1. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution at a ratio of 1:1. The mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes, and then allowed to stand for 30 minutes for phase separation to obtain a loaded organic phase. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution at a ratio of 4:1, and oscillated for stripping for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0054] Example 9

[0055] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.3. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1. The mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes, and then allowed to stand for 30 minutes for phase separation to obtain a loaded organic phase. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1, and oscillated for stripping for 10 minutes. The single-stage extraction rate was calculated as shown in Table 2.

[0056] Example 10

[0057] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.4. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1. The mixture was shaken at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 10 minutes, and then allowed to stand for 30 minutes for phase separation to obtain a loaded organic phase. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1, and oscillated for stripping for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0058] Example 11

[0059] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 65°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1. The mixture was shaken for 10 minutes at an ambient temperature of 50°C, with an amplitude of 40 mm and a rotation frequency of 300 RPM. After standing for 30 minutes for phase separation, a loaded organic phase was obtained. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1 and subjected to oscillation stripping for 10 minutes. The single-stage extraction rate was calculated as shown in Table 2.

[0060] Example 12

[0061] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 85°C and a stirring speed of 180 RPM for 4 h to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1. The mixture was shaken for 10 min at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM. After standing for 30 min for phase separation, a loaded organic phase was obtained. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1 and subjected to oscillation stripping for 10 min. The single-stage extraction rate was calculated as shown in Table 2.

[0062] Example 13

[0063] Tetrabutylammonium bromide was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 130 RPM for 5 h to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1. The mixture was shaken at an ambient temperature of 45°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM for 8 min, and then allowed to stand for 45 min for phase separation to obtain a loaded organic phase. The vanadium-loaded deep eutectic solvent was mixed with a 1.8 mol / L NaCl solution in a ratio of 5:1, and oscillated for stripping for 10 min. The single-stage extraction rate was calculated, see Table 2.

[0064] Comparative Example 1

[0065] Tetrapropylammonium chloride was used as a hydrogen bond acceptor, n-octanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1. The mixture was shaken for 10 minutes at an ambient temperature of 50°C, an amplitude of 40 mm, and a rotation frequency of 300 RPM. After standing for 30 minutes for phase separation, a loaded organic phase was obtained. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1, and oscillated for stripping for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0066] Comparative Example 2

[0067] Tetrabutylammonium chloride was used as a hydrogen bond acceptor, n-hexanol was used as a hydrogen bond donor, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor was 1:1.2. The reaction was carried out at a heating temperature of 75°C and a stirring speed of 180 RPM for 4 hours to prepare a hydrophobic deep eutectic solvent. The prepared hydrophobic deep eutectic solvent was mixed with a vanadium arsenic solution in a ratio of 1:1. The mixture was shaken for 10 minutes at an ambient temperature of 50°C, with an amplitude of 40 mm and a rotation frequency of 300 RPM. After standing for 30 minutes to separate the phases, the loaded organic phase was discarded. The vanadium-loaded deep eutectic solvent was mixed with a 1.5 mol / L NaCl solution in a ratio of 4:1, and oscillated and stripped for 10 minutes. The single-stage extraction rate was calculated, see Table 2.

[0068] Table 2

[0069] As can be seen from Table 2, Example 4 is the optimal example. That is, when the hydrogen bond acceptor is tetrabutylammonium bromide and the hydrogen bond donor is n-octanol, tetrabutylammonium bromide and n-octanol are mixed in a molar ratio of 1:1.2, and the mixture is reacted at a heating temperature of 75° C. and a stirring speed of 180 RPM for 4 hours. The prepared hydrophobic deep eutectic solvent has the best extraction effect for vanadium, with a single-stage vanadium extraction rate of up to 80.21%. When tetrabutylammonium bromide is replaced by tetrabutylammonium chloride, the single-stage vanadium extraction rate is also high, reaching over 75%. However, when tetrabutylammonium bromide is replaced by tetrapropylammonium chloride, the single-stage vanadium extraction rate is only 45.78%. When other fatty alcohols such as n-nonanol and n-decanol are used, the single-stage vanadium extraction rate is over 65%, while when n-hexanol is used, the single-stage vanadium extraction rate is only 38.54%. It can be seen that the hydrogen bond network formed by suitable hydrogen bond donors and hydrogen bond acceptors under specific reaction conditions is more conducive to the extraction of vanadium from vanadium arsenic solution.

[0070] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for extracting and separating vanadium from a vanadium-arsenic solution using a hydrophobic deep eutectic solvent, characterized in that: The following steps are involved: S100, preparation of a hydrophobic deep eutectic solvent: mixing a hydrogen bond acceptor and a hydrogen bond donor and reacting them to form a hydrogen bond network; The hydrogen bond acceptor includes tetrabutylammonium chloride or tetrabutylammonium bromide; The hydrogen bond donor includes any one of n-octanol, n-nonanol or n-decanol; S200, extraction and separation of vanadium: mixing the hydrophobic low eutectic solvent with the vanadium-arsenic solution, shaking, standing for phase separation, and stripping after phase separation.

2. The method according to claim 1, characterized in that In step S100, the reaction temperature is 65°C to 85°C, the reaction time is 3h to 5h, and the stirring speed is 100RPM to 200RPM.

3. The method according to claim 1, characterized in that In step S100, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:(1-1.4).

4. The method according to claim 3, characterized in that In step S100, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:1.

2.

5. The method according to claim 1, characterized in that: The viscosity of the hydrophobic deep eutectic solvent is 110 cP to 180 cP.

6. The method according to claim 5, characterized in that The viscosity of the hydrophobic deep eutectic solvent is 115 cP to 130 cP.

7. The method according to claim 1, characterized in that In step S200, mixing the hydrophobic deep eutectic solvent with the vanadium arsenic solution comprises: The hydrophobic low eutectic solvent and the vanadium arsenic solution are mixed in a volume ratio of 1:(1-2).

8. The method according to claim 1, characterized in that: The concentration of vanadium ions in the vanadium-arsenic solution is 9 g / L to 12 g / L, and the concentration of arsenic ions is 8 g / L to 8.5 g / L.

9. The method according to claim 1, characterized in that: In step S200, the oscillating includes oscillating at a temperature between 40°C and 60°C; The standing time for the standing phase separation is 30 min to 50 min.

10. The method according to claim 1, characterized in that In step S200, the stripping after phase separation includes: Obtain a vanadium-loaded hydrophobic low eutectic solvent, mix a stripping agent with the vanadium-loaded hydrophobic low eutectic solvent in a volume ratio of (3-5):1, and perform oscillation stripping for 5 to 10 minutes.

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