A method for preparing high-purity ammonium tungstate solution

Abstract

The application belongs to the technical field of metallurgy, and particularly relates to a preparation method of high-purity ammonium tungstate solution. The application provides a preparation method of high-purity ammonium tungstate solution, which comprises the following steps: performing first adsorption on a crude ammonium tungstate solution to obtain saturated adsorption resin; sequentially performing elution and desorption on the saturated adsorption resin to obtain tungsten-containing desorption solution; performing purification on the tungsten-containing desorption solution to obtain tungsten-containing purified solution; and performing second adsorption on the tungsten-containing purified solution to obtain the high-purity ammonium tungstate solution. Compared with the existing solvent extraction, the application adopts the chromatography column method to separate and purify tungsten, and the tungsten can be obtained through adsorption, elution, desorption, purification and secondary adsorption, so that the process flow is simple, and the reagent consumption is small. The experimental results show that the purity of the ammonium tungstate solution obtained by the application can reach more than 99.9995%.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metallurgy, and particularly relates to a preparation method of high-purity ammonium tungstate solution. BACKGROUND

[0002] High-performance tungsten material is one of the materials with wide application prospects in the 21st century. The purity of tungsten material required by the electronic and microelectronic industry is 99.999-99.9999%, or even higher. Ammonium paratungstate (APT) is the most important raw material for preparing tungsten material, and the purity of APT has an important influence on the performance of subsequent tungsten products.

[0003] A method for producing high-purity ammonium paratungstate from tungsten waste is disclosed in Chinese Patent No. CN105314683A. The tungsten waste is calcined into tungsten oxide, then decomposed with ammonia water, filtered, vacuum distilled, and washed with ammonium nitrate after obtaining ammonium paratungstate crystals, thereby obtaining high-purity ammonium paratungstate. The invention needs to grind the tungsten waste and then calcine it, which is difficult to operate. The influence of the concentration of the primary and secondary ion exchange front liquid tungsten, the depth of the eluent, the crystallization rate of sodium tungstate and ammonium paratungstate, and other factors on the impurity removal effect is disclosed in the document "Process optimization of super-high-purity ammonium paratungstate prepared by secondary ion exchange saturation adsorption method (Zhao Lifu, Xiao Xueyou, Wan Lingsheng, et al. Process optimization of super-high-purity ammonium paratungstate prepared by secondary ion exchange saturation adsorption method [J]. China Tungsten Industry, 2009, 24(4): 4. DOI:10.3969 / j.issn.1009-0622.2009.04.009.)". However, this process has a long process flow, a large amount of high-salt wastewater, and a large environmental protection pressure. Chinese Patent No. CN112678871A discloses a preparation method of super-high-purity ammonium paratungstate. The 0-grade ammonium paratungstate is sequentially calcined and dissolved to obtain an intermediate liquid through solid-liquid separation; the intermediate liquid is subjected to anion exchange treatment to obtain a desorption liquid, and the desorption liquid is sequentially subjected to impurity removal treatment, solid-liquid separation, and cation exchange treatment, and then subjected to second desorption and crystallization to obtain the super-high-purity ammonium paratungstate with a purity of 99.9999% or above, which meets the requirements of the electronic and microelectronic industry. However, the invention needs two adsorption-desorption operations, and also has the problems of a large amount of high-salt wastewater and a large environmental protection pressure. SUMMARY

[0004] The purpose of the present application is to provide a preparation method of high-purity ammonium tungstate solution. The method provided by the present application is simple to operate and environmentally friendly.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] The present application provides a preparation method of high-purity ammonium tungstate solution, comprising the following steps:

[0007] The crude ammonium tungstate solution is subjected to first adsorption to obtain saturated adsorption resin;

[0008] The saturated adsorption resin was sequentially eluted and desorbed to obtain a tungsten-containing desorption solution.

[0009] The tungsten-containing desorption solution is purified to obtain a tungsten-containing purified solution.

[0010] The tungsten-containing purified liquid is subjected to a second adsorption to obtain the high-purity ammonium tungstate solution.

[0011] Preferably, the pH value of the crude ammonium tungstate solution is 2 to 4.

[0012] Preferably, the adsorption resin used for the first adsorption is an ammonia-based extraction resin;

[0013] The ammonia-based extraction resin is obtained by in-situ compounding of a styrene-divinylbenzene macroporous copolymer and an amine extractant.

[0014] Preferably, the amine extractant includes one or more of the following: tri(octyl-decyl)alkyl tertiary amine N235 extractant, secondary carbon primary amine extractant N1923, and trioctylmethylammonium chloride N263 extractant;

[0015] The mass content of amine extractant in the ammonia-based extraction resin is 5-60%.

[0016] Preferably, the detergent used for rinsing includes water and / or an acidic solution; the acidic solution includes one or more of nitric acid solution, formic acid solution, and acetic acid solution;

[0017] The mass of the detergent is 0.5 to 5 times the mass of the adsorption resin used in the first adsorption.

[0018] Preferably, the desorption agent used is ammonia water; the concentration of the ammonia water is 0.1 to 13 mol / L.

[0019] Preferably, the purifying agent used in the purification includes sulfide salts, copper salts, and magnesium salts.

[0020] Preferably, the adsorption resin used in the second adsorption is an acidic phosphorus extraction resin;

[0021] The acidic phosphorus extracting resin is obtained by in-situ emulsion suspension polymerization of styrene-divinylbenzene macroporous copolymer and acidic phosphorus extractant.

[0022] Preferably, the acidic phosphorus extractant includes one or more of di(2-ethylhexyl) phosphate, (2-ethylhexyl)phosphonic acid-mono(2-ethylhexyl) ester, di(2,4,4-trimethylpentyl)phosphonic acid, di(2-ethylhexyl)phosphonic acid, and di(2-ethylhexyl)phosphonic acid.

[0023] The acidic phosphorus extractant in the acidic phosphorus extraction resin has a mass content of 5-60%.

[0024] Preferably, the purity of the high-purity ammonium tungstate solution is 99.9995% or higher.

[0025] This invention provides a method for preparing a high-purity ammonium tungstate solution, comprising the following steps: subjecting a crude ammonium tungstate solution to a first adsorption to obtain a saturated adsorption resin; sequentially rinsing and desorbing the saturated adsorption resin to obtain a tungsten-containing desorption solution; purifying the tungsten-containing desorption solution to obtain a tungsten-containing purified solution; and subjecting the tungsten-containing purified solution to a second adsorption to obtain the high-purity ammonium tungstate solution.

[0026] Compared with existing solvent extraction methods, this invention uses column chromatography to separate and purify tungsten. The process involves adsorption, elution, desorption, purification, and secondary adsorption, resulting in a simple process with low reagent consumption. Experimental results show that the purity of the ammonium tungstate solution obtained by this invention can reach over 99.9995%. Attached Figure Description

[0027] Figure 1 This is a schematic flowchart of the preparation method provided by the present invention. Detailed Implementation

[0028] This invention provides a method for preparing a high-purity ammonium tungstate solution, comprising the following steps:

[0029] The crude ammonium tungstate solution was subjected to the first adsorption to obtain a saturated adsorption resin.

[0030] The saturated adsorption resin was sequentially eluted and desorbed to obtain a tungsten-containing desorption solution.

[0031] The tungsten-containing desorption solution is purified to obtain a tungsten-containing purified solution.

[0032] The tungsten-containing purified liquid is subjected to a second adsorption to obtain the high-purity ammonium tungstate solution.

[0033] In this invention, unless otherwise specified, all raw materials used in the preparation are superior-grade pure products well known to those skilled in the art.

[0034] In this invention, a crude ammonium tungstate solution is subjected to a first adsorption process to obtain a saturated adsorption resin.

[0035] The present invention does not have a particular limitation on the source of the crude ammonium tungstate solution; any source well known to those skilled in the art may be used. In the present invention, the pH value of the crude ammonium tungstate solution is preferably 2-4, more preferably 2.5-3.5, and even more preferably 3. In the present invention, the WO3 concentration in the crude ammonium tungstate solution is preferably 50-200 g / L.

[0036] In this invention, the adsorption resin used for the first adsorption is preferably an ammonia-based extraction resin; the ammonia-based extraction resin is preferably obtained by in-situ compounding of a styrene-divinylbenzene macroporous copolymer and an amine extractant. In this invention, the amine extractant preferably includes one or more of tri(octyl-decyl)alkyl tertiary amine N235 extractant, secondary carbon primary amine extractant N1923, and trioctylmethylammonium chloride N263 extractant. In this invention, the mass content of the amine extractant in the ammonia-based extraction resin is preferably 5-60%. In this invention, the preparation of the ammonia-based extraction resin preferably includes: mixing the styrene-divinylbenzene macroporous copolymer, the amine extractant, and an organic solvent, followed by rotary evaporation to obtain the ammonia-based extraction resin. In this invention, the organic solvent preferably includes petroleum ether or n-heptane. This invention does not impose special limitations on the amount of the organic solvent or the rotary evaporation process; methods well known to those skilled in the art can be used.

[0037] In a specific embodiment of the present invention, the first adsorption process is preferably as follows: the ammonia-based extraction resin is loaded into a chromatography column, and the crude ammonium tungstate solution is flowed through the chromatography column using a plunger pump; the tungsten concentration in the effluent is sampled and detected every 5 minutes; when the WO3 concentration in the effluent reaches 1 g / L, the addition of the crude ammonium tungstate solution is stopped, and saturated adsorption resin is obtained. The present invention does not impose any special limitations on the loading amount of the ammonia-based extraction resin or the flow rate of the crude ammonium tungstate solution; methods well known to those skilled in the art can be used. In a specific embodiment of the present invention, the loading amount of the ammonia-based extraction resin is preferably 500 g, and the flow rate of the crude ammonium tungstate solution is preferably 5 mL / min.

[0038] After obtaining the saturated adsorption resin, the present invention sequentially washes and desorbs the saturated adsorption resin to obtain a tungsten-containing desorption solution.

[0039] In this invention, the detergent used for rinsing preferably includes water and / or an acidic solution. In this invention, the acidic solution preferably includes one or more of nitric acid solution, formic acid solution, and acetic acid solution; the concentration of the acidic solution is preferably 1*10⁻⁶. -7 ~0.5 mol / L. In this invention, the mass of the detergent is preferably 0.5 to 5 times the mass of the adsorption resin used for the first adsorption. In this invention, the flow rate of the detergent is preferably 15 mL / min.

[0040] In this invention, the desorbent used is preferably ammonia; the concentration of the ammonia is preferably 0.1–13 mol / L. The flow rate of the ammonia is preferably 5 mL / min. During the desorption process, the concentration of WO3 in the resulting desorbate is preferably monitored; when the concentration of WO3 in the desorbate is less than 0.1 g / L, the addition of the desorbent is stopped, i.e., desorption is stopped. The desorbed resin is preferably returned to the first adsorption process for reuse.

[0041] After obtaining the tungsten-containing desorption solution, the present invention purifies the tungsten-containing desorption solution to obtain a tungsten-containing purified solution.

[0042] In this invention, the purifying agent preferably includes sulfide salts, copper salts, and magnesium salts. Preferably, the sulfide salt includes ammonium sulfide or sodium sulfide; the copper salt preferably includes copper sulfate; and the magnesium salt preferably includes magnesium sulfate. The molar ratio of the sulfide salt to the molar ratio of molybdenum in the tungsten-containing desorption solution is preferably 5–10:1; the molar ratio of the copper salt to the molar ratio of molybdenum in the tungsten-containing desorption solution is preferably 5–10:1; and the molar ratio of the magnesium salt to the total molar ratio of phosphorus, arsenic, and silicon in the tungsten-containing desorption solution is preferably 5–10:1. In this invention, purification can remove impurity ions such as Mo, P, As, and Si from the tungsten-containing desorption solution.

[0043] In this invention, the purification process preferably includes: sequentially adding magnesium salt, sulfide salt, and copper salt to the tungsten-containing desorption solution, stirring and mixing, and filtering to obtain a tungsten-containing purified solution. In this invention, the stirring time is preferably 0.5–24 h, and the stirring temperature is preferably 20–60 °C.

[0044] After obtaining the tungsten-containing purified liquid, the present invention performs a second adsorption on the tungsten-containing purified liquid to obtain the high-purity ammonium tungstate solution.

[0045] In this invention, the adsorption resin used for the second adsorption is preferably an acidic phosphorus extraction resin; the acidic phosphorus extraction resin is preferably obtained by in-situ emulsion suspension polymerization of a styrene-divinylbenzene macroporous copolymer and an acidic phosphorus extractant. In this invention, the acidic phosphorus extractant preferably includes one or more of di(2-ethylhexyl)phosphate (P204), (2-ethylhexyl)phosphonic acid-mono(2-ethylhexyl) ester (P507), di(2,4,4-trimethylpentyl)phosphonic acid (Cyanex 272), di(2-ethylhexyl)phosphonic acid (P229), and di(2-ethylhexyl)phosphonic acid (P227); the mass content of the acidic phosphorus extractant in the acidic phosphorus extraction resin is preferably 5-60%.

[0046] In this invention, the preparation method of the acidic phosphorus extraction resin is preferably suspension polymerization; the suspension polymerization method preferably includes the following steps:

[0047] Water, gelatin, ammonium thiocyanate, and surfactant are mixed to obtain an aqueous phase;

[0048] Styrene, divinylbenzene, and an initiator are mixed to obtain an oil phase;

[0049] The oil phase and the aqueous phase are mixed and reacted. After the resin forms spheres, an acidic phosphorus extractant is added to carry out an in-situ polymerization reaction to obtain the acidic phosphorus extractant resin.

[0050] This invention mixes water, gelatin, ammonium thiocyanate, and a surfactant to obtain an aqueous phase. In this invention, the surfactant preferably includes one or more of polyvinyl alcohol, hydroxymethyl cellulose, and TX-100; the gelatin and surfactant can reduce the interfacial tension of the liquid, resulting in a higher degree of dispersion of monomer droplets, and can also increase the viscosity of the polymerization medium, thereby hindering the collision and adhesion between monomer droplets, and can also form a protective film on the surface of the monomer droplets to prevent droplet aggregation.

[0051] In this invention, the concentration of gelatin in the aqueous phase is preferably 0.005–0.02 g / mL, more preferably 0.01–0.015 g / mL; the mass ratio of ammonium thiocyanate to gelatin is preferably 1:5–20, more preferably 1:8–15, and more preferably 1:10; the volume fraction of surfactant in the aqueous phase is preferably 0.01%–0.1%.

[0052] This invention involves mixing styrene, divinylbenzene, and an initiator to obtain an oil phase. In this invention, the volume ratio of styrene to divinylbenzene is preferably 100:1 to 100, more preferably 100:20 to 80, even more preferably 100:40 to 60, and most preferably 100:50. This invention does not have any special requirements for the initiator; any initiator well-known to those skilled in the art can be used. In a specific embodiment of the present invention, the initiator is preferably a peroxide and / or persulfate, more preferably one or more of hydroxydiisopropylbenzene peroxide, benzoyl peroxide and potassium persulfate, and even more preferably benzoyl peroxide; the concentration of the initiator in the oil phase is preferably 0.001-0.01 g / mL, more preferably 0.003-0.008 g / mL, and even more preferably 0.004-0.006 g / mL; the ratio of the total volume of styrene and divinylbenzene to the volume of the acidic phosphorus extractant is preferably 100:(10-120), more preferably 100:(50-120), even more preferably 100:(80-120), and most preferably 100:100.

[0053] In a specific embodiment of the present invention, styrene and divinylbenzene are preferably added to a separatory funnel, then washed twice with an aqueous sodium hydroxide solution, and the washed mixture is washed with water until neutral. Then an initiator is added to obtain an oil phase. The concentration of the aqueous sodium hydroxide solution is preferably 1 mol / L. The ratio of the volume of the aqueous sodium hydroxide solution used for a single wash to the total volume of the styrene and divinylbenzene is preferably 133:400. The washing is preferably performed by adding the aqueous sodium hydroxide solution to a separatory funnel, shaking, separating the liquid, and discarding the aqueous phase.

[0054] After obtaining the aqueous phase and the oil phase, the present invention mixes the oil phase and the aqueous phase for reaction. After the resin forms spheres, an acidic phosphorus extractant is added for in-situ polymerization to obtain the acidic phosphorus extractant resin. In the present invention, the preferred volume ratio of the aqueous phase to the oil phase is (2-5):1, more preferably (3-5):1. In a specific embodiment of the present invention, since gelatin is not easily soluble in water, it is preferable to first heat the aqueous phase until the gelatin is completely dissolved, and then slowly add the oil phase while stirring; the preferred heating temperature is 50°C.

[0055] In this invention, the preferred temperature for the reaction of the oil phase and the aqueous phase is 70–85°C. In a specific embodiment of this invention, preferably after the oil phase has been added, the temperature of the mixture is raised to 70–85°C to carry out the reaction, and the reaction process is observed. When the resin just begins to spherize, an acidic phosphorus extractant is added to the system to carry out an in-situ polymerization reaction. In this invention, the in-situ polymerization reaction preferably includes a first stage and a second stage carried out sequentially. The preferred temperature for the first stage is 70–85°C, and the preferred time is 1–3 hours. The preferred temperature for the second stage is 80–95°C, and the preferred time is 0.3–1 hour.

[0056] After the in-situ polymerization reaction is completed, the product is preferably sieved and dried to obtain the extracted resin. The mesh size of the sieve used for sieving is preferably 10 to 300 mesh, more preferably 100 to 200 mesh. The drying method is preferably air drying. In a specific embodiment of the present invention, the sieved resin is preferably washed with water and then dried.

[0057] Prior to the second adsorption, the present invention preferably includes saponifying the adsorption resin used for the second adsorption. In the present invention, the saponifying agent used for the saponification is preferably ammonia. In the present invention, the degree of saponification of the adsorption resin obtained after saponification is preferably 5-70%.

[0058] In a specific embodiment of the present invention, the second adsorption process is preferably as follows: the acidic phosphorus extraction resin is packed into a chromatography column, the tungsten-containing purified solution is passed through the chromatography column, and the resulting effluent is a high-purity ammonium tungstate solution. The present invention does not impose any particular limitation on the packing amount of the acidic phosphorus extraction resin or the flow rate of the tungsten-containing purified solution; methods well known to those skilled in the art can be used. In a specific embodiment of the present invention, the preferred packing amount of the acidic phosphorus extraction resin is 500 g, and the preferred flow rate of the tungsten-containing purified solution is 5 mL / min.

[0059] After the second adsorption, the present invention preferably includes regenerating the adsorbed resin; the regeneration process preferably includes: passing a desorbent through the adsorbed resin, detecting the content of impurity ions in the outflowing desorbent, and stopping the addition of desorbent when the content of impurity ions in the desorbent is lower than 0.1 g / L; then adding ammonia water for saponification, controlling the degree of saponification to 5-70%, and returning it to the second adsorption for recycling. In the present invention, the desorbent preferably includes an acidic solution; the acidic solution preferably includes a nitric acid solution and / or a formic acid solution; the concentration of the acidic solution is preferably 1.0-8.0 mol / L.

[0060] The adsorption resin used in this invention comprises a styrene-divinylbenzene macroporous copolymer and an extractant in situ composite thereon, namely, a styrene-divinylbenzene composite extractant is prepared in one step by an impregnation method. The composite extractant is not easily detached from the styrene-divinylbenzene copolymer, and the extraction resin can be reused after desorption, thus reducing the cost of separation and purification.

[0061] A schematic flowchart of the preparation method provided by this invention is shown below. Figure 1 As shown.

[0062] In this invention, the purity of the high-purity ammonium tungstate solution is preferably 99.9995% or higher. Furthermore, the purity of the high-purity ammonium tungstate solution is preferably tested according to the national standard for grade 0 ammonium paratungstate.

[0063] To further illustrate the present invention, a method for preparing a high-purity ammonium tungstate solution provided by the present invention will be described in detail below with reference to the accompanying drawings and embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0064] Example 1

[0065] 1000g of styrene-divinylphenyl macroporous blank resin, 300mL of tri(octyl-decyl)alkyl tertiary amine extractant N235 and 500mL of petroleum ether were mixed and the solvent was evaporated in a rotary evaporator to obtain 1200g of ammonia-containing extractant resin.

[0066] The synthesis method of acidic phosphorus-based extraction resin is as follows: In a 5L reactor, 3000mL of pure water, 36g of gelatin, 3.6g of ammonium thiocyanate, and 1mL of TX-100 are added sequentially. The mixture is heated to 50℃ in a water bath with mechanical stirring until the gelatin is completely dissolved, yielding the aqueous phase. In a pear-shaped separatory funnel, 300mL of styrene and 100mL of 55% divinylbenzene are added and mixed. Then, 133mL of 1mol / L sodium hydroxide aqueous solution is added, and the mixture is shaken for 5 minutes. After standing and phase separation, the aqueous portion is discarded. The mixture is then washed once more with the same phase. The purified styrene-divinylbenzene is then washed with pure water until neutral. 3.6g of benzoyl peroxide is then added and mixed to obtain the oil phase. While stirring, the oil phase is slowly added to the aqueous phase. After the oil phase is completely added, the water bath temperature is raised to 80℃, and the resin synthesis process is observed. When the resin forms spheres, 400mL of... Cyanex272 was reacted at a constant temperature for 2 hours, and then the water bath temperature was raised to 90°C and kept at that temperature for 0.5 hours. The light yellow spherical material obtained by wet sieving (particle size greater than 100 mesh) was washed with pure water, filtered, and the product was air-dried to obtain 710g of acidic phosphorus extraction resin with a Cyanex272 content of 50%.

[0067] 500g of ammonia-containing extraction resin was loaded into a chromatography column. Crude ammonium tungstate solution (with WO3 concentration of 195.24g / L and pH value of 3.60) was flowed through the chromatography column at a flow rate of 5mL / min using a plunger pump for the first adsorption. The tungsten concentration in the effluent was measured every 5min. When the WO3 concentration in the effluent reached 1g / L, the addition of crude ammonium tungstate solution was stopped, and saturated adsorption resin was obtained. 305mL of crude ammonium tungstate solution was consumed.

[0068] 500 mL of deionized water was added to a chromatography column packed with saturated adsorption resin for elution at a flow rate of 15 mL / min. The effluent was collected, and the WO3 concentration in the effluent was 12.64 g / L. 3.0 mol / L high-purity ammonia was added to the eluted resin for desorption at a flow rate of 5 mL / min. The WO3 concentration in the desorbate was measured. When the WO3 concentration was less than 0.1 g / L, the addition of high-purity ammonia was stopped, yielding 300 mL of tungsten-containing desorbate with a WO3 concentration of 173.60 g / L. The desorbed resin can be returned to the first adsorption stage for reuse.

[0069] 2g MgSO4, 1g (NH4)2S and 3g CuSO4 were added to the obtained tungsten-containing desorption solution in sequence, and the mixture was stirred for 30 minutes and then filtered to obtain 322mL of tungsten-containing purified solution with a WO3 concentration of 160.42g / L.

[0070] 500g of acidic phosphorus extraction resin was packed into a chromatography column, and the phosphorus extraction resin was saponified with ammonia water to control the degree of saponification at 40%. The resulting tungsten-containing purified solution was flowed through the saponified chromatography column at a flow rate of 5mL / min, and the eluent was collected, which was a high-purity ammonium tungstate solution. A total of 308mL of high-purity ammonium tungstate solution was collected, in which the WO3 concentration was 156.97g / L and the purity was 99.9997%.

[0071] Example 2

[0072] 1000g of styrene-divinylphenyl macroporous blank resin, 300mL of secondary carbon primary amine extractant N1923 and 500mL of n-heptane were mixed, and the solvent was evaporated in a rotary evaporator to obtain 1230g of ammonia-containing extractant resin.

[0073] Acidic phosphorus extraction resin was prepared according to the method in Example 1, except that the amount of Cyanex272 added was changed to 175 mL, and 505 g of CL-Cyanex272 acidic phosphorus extraction resin with a concentration of 30% was prepared.

[0074] 500g of ammonia-containing extraction resin was loaded into a chromatography column. The crude ammonium tungstate solution (WO3 concentration of 195.24g / L, pH value of 3.60) was flowed through the chromatography column at a flow rate of 5mL / min using a plunger pump for the first adsorption. The tungsten concentration in the effluent was measured every 5min. When the WO3 concentration in the effluent reached 1g / L, the addition of crude ammonium tungstate solution was stopped, and saturated adsorption resin was obtained. 313mL of crude ammonium tungstate solution was consumed.

[0075] 500 mL of deionized water was added to a chromatography column packed with saturated adsorption resin for elution at a flow rate of 15 mL / min. The eluent was collected, and the WO3 concentration in the eluent was 10.72 g / L. 3.0 mol / L high-purity ammonia was added to the eluted resin for desorption at a flow rate of 5 mL / min. The WO3 concentration in the eluent was measured. When the WO3 concentration was less than 0.1 g / L, the addition of high-purity ammonia was stopped, yielding 305 mL of tungsten-containing eluent with a WO3 concentration of 175.27 g / L. The desorbed resin can be returned to the first adsorption stage for reuse.

[0076] 2g MgSO4, 1g (NH4)2S and 3g CuSO4 were added to the obtained tungsten-containing desorption solution in sequence, and the mixture was stirred for 30 minutes and then filtered to obtain 318mL of tungsten-containing purified solution with a WO3 concentration of 167.83g / L.

[0077] 500g of acidic phosphorus extraction resin was packed into a chromatography column, and the phosphorus extraction resin was saponified with ammonia water to control the degree of saponification at 60%. The resulting tungsten-containing purified solution was flowed through the saponified chromatography column at a flow rate of 5mL / min, and the eluent was collected to obtain a high-purity ammonium tungstate solution. A total of 311mL of high-purity ammonium tungstate solution was obtained, in which the WO3 concentration was 161.62g / L and the purity was 99.9996%.

[0078] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. Other embodiments can be obtained based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preparing a high purity ammonium tungstate solution, characterized by, The method comprises the following steps: The crude ammonium tungstate solution is subjected to first adsorption to obtain saturated adsorption resin; the adsorption resin used in the first adsorption is an ammonia type elution resin; the ammonia type elution resin is obtained by in-situ compounding of styrene-divinylbenzene macroporous copolymer and an amine type extractant; the amine type extractant comprises one or more of tri (octyl-decyl) tertiary amine N235 extractant, secondary carbon primary amine extractant N1923 and trioctylmethylammonium chloride N263 extractant; The saturated adsorption resin is subjected to elution and desorption in sequence to obtain a tungsten-containing desorption solution; The tungsten-containing desorption solution is subjected to purification to obtain a tungsten-containing purified solution; the purifying agent used in the purification comprises a sulfide salt, a copper salt and a magnesium salt; The tungsten-containing purified solution is subjected to second adsorption to obtain the high-purity ammonium tungstate solution; the adsorption resin used in the second adsorption is an acid phosphorus type elution resin; the acid phosphorus type elution resin is obtained by in-situ emulsion suspension polymerization of styrene-divinylbenzene macroporous copolymer and an acid phosphorus type extractant; the acid phosphorus type extractant comprises one or more of di (2-ethylhexyl) phosphate, (2-ethylhexyl) phosphonic acid-mon (2-ethylhexyl) ester, di (2, 4, 4-trimethylpentyl) phosphonic acid, di (2-ethylhexyl) phosphonic acid and di (2-ethylhexyl) phosphinic acid.

2. The production method according to claim 1, characterized by, The pH value of the crude ammonium tungstate solution is 2-4.

3. The preparation method according to claim 1, characterized in that, The mass content of the amine type extractant in the ammonia type elution resin is 5-60%.

4. The method of claim 1, wherein, The washing agent used in the elution comprises water and / or an acid solution; the acid solution comprises one or more of nitric acid solution, formic acid solution and acetic acid solution; The mass of the washing agent is 0.5-5 times the mass of the adsorption resin used in the first adsorption.

5. The preparation method according to claim 1, characterized in that, The desorption agent used in the desorption is aqueous ammonia; the concentration of the aqueous ammonia is 0.1-13 mol / L.

6. The method of claim 1, wherein, The mass content of the acid phosphorus type extractant in the acid phosphorus type elution resin is 5-60%.

7. The preparation method according to claim 1, characterized in that, The purity of the high-purity ammonium tungstate solution is higher than 99.9995%.

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