Method for preparing high-purity cobalt solution from nickel raw material associated cobalt

Abstract

The invention discloses a method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material, which comprises the following steps: pulping the nickel raw material associated with cobalt to obtain pulpified ore pulp; adjusting the pH value of the pulpified ore pulp to 1.5-2.0 by using an acid solution, and carrying out acid leaching reaction to obtain acid leaching slurry; the pH value of the acid leaching slurry is adjusted to 5.2-5.5 through alkali slurry, and a nickel-cobalt extracting solution and filter residues are obtained after precipitation reaction; extracting the nickel-cobalt extracting solution by using a P204 extraction organic phase to obtain nickel-cobalt raffinate; carrying out extraction and reverse extraction on the nickel-cobalt raffinate by utilizing a P507 and C272 synergistic extraction organic phase to obtain cobalt raffinate; and the cobalt raffinate is subjected to extraction and reverse extraction through the P507 extraction organic phase, and the high-purity cobalt solution is obtained. According to the method, the nickel raw material associated with cobalt is sequentially subjected to acid leaching, alkali precipitation, extraction and impurity removal, separation of nickel and cobalt is achieved, the technological process is short, the production cost is low, and refining of the nickel solution and the cobalt solution can be achieved at the same time.

Description

Technical Field

[0001] The invention belongs to the technical field of cobalt hydrometallurgy, and in particular relates to a method for preparing a high-purity cobalt solution from a nickel raw material and associated cobalt. Background Art

[0002] Cobalt is an important strategic metal, which is widely used in the fields of industry, military, medicine and new energy. With the sustained and stable growth of China's economy, cobalt is widely used in various sectors of the national economy. Therefore, the demand for cobalt in the domestic and foreign markets is increasing, and the supply pressure of cobalt resources is gradually increasing.

[0003] Cobalt in the earth's crust exists mainly as an associated element in nickel, copper, iron or silver ores. At present, when using laterite nickel ore for wet smelting to extract nickel and cobalt, the process of high-pressure acid leaching-thickener washing and separation-iron and aluminum removal-nickel-cobalt precipitation is generally used to prepare nickel cobalt hydroxide intermediate products or nickel cobalt sulfide intermediate products. The intermediate products are further produced by leaching-purification-evaporation crystallization or electrolytic deposition processes to produce nickel sulfate, cobalt sulfate or electrolytic nickel, electrolytic cobalt and other final products. For nickel cobalt hydroxide as an intermediate product, a solvent extraction process is generally used for treatment, and nickel and cobalt are separated to obtain a cobalt solution, which then enters the cobalt leaching system and undergoes refining processes such as cobalt leaching, callback impurity removal, resin impurity removal, and extraction impurity removal.

[0004] The above-mentioned process for preparing refined cobalt solution with nickel-cobalt intermediates has problems such as long process flow and high production cost. Therefore, it is urgent to develop a cobalt solution refining process with a wide range of applications, short process flow and low production cost. Summary of the invention

[0005] In order to overcome the above-mentioned defects of the prior art, the purpose of the present invention is to provide a method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material, so as to solve the technical problems of the existing cobalt solution refining process with a long flow and high cost.

[0006] To achieve the above object, the present invention is implemented through the following technical solutions: The present invention provides a method for preparing a high-purity cobalt solution from a nickel raw material and associated cobalt, comprising the following steps: (1) Slurrying the nickel raw material with associated cobalt to obtain pulped ore pulp; (2) Using an acid solution to adjust the pH of the pulp to 1.5-2.0, and subjecting the mixture to an acid leaching reaction to obtain an acid leaching slurry; (3) Using alkaline slurry to adjust the pH of the acid leaching slurry to 5.2-5.5, and obtaining nickel-cobalt extract and filter residue after precipitation reaction and solid-liquid separation; (4) extracting the nickel-cobalt extract solution with an organic phase using P204 to obtain a nickel-cobalt raffinate; (5) extracting the nickel-cobalt raffinate using P507 and C272 as a synergistic extraction organic phase to obtain a cobalt-loaded organic phase 1, and stripping the cobalt-loaded organic phase 1 to obtain a cobalt raffinate; (6) extracting the cobalt raffinate with a P507 organic phase to obtain a cobalt-loaded organic phase II, and back-extracting the cobalt-loaded organic phase II to obtain a high-purity cobalt solution.

[0007] Preferably, in step (1), the nickel raw material associated with cobalt comprises nickel cobalt hydroxide; the solution used for pulping is one or more of pickling water and tap water; and the solid-liquid ratio of the pulping slurry is 1:1-1.5.

[0008] Preferably, in step (2), the acid solution is one or more of a sulfuric acid solution, a hydrochloric acid solution, and a nitric acid solution; the temperature of the acid leaching reaction is 60-80° C., and the reaction time is 2-3 h.

[0009] Preferably, in step (3), the alkaline slurry includes one or more of nickel cobalt hydroxide slurry and lime milk; the precipitation reaction temperature is 60-80°C and the reaction time is 20-40 min.

[0010] Preferably, in step (4), the P204 extracted organic phase is obtained by mixing P204 and a diluent and then saponifying with an alkali solution; the volume ratio of P204 to the diluent is 1:2.5-4; the diluent is one or more of sulfonated kerosene and light white oil; the saponification rate is 10-40%, and the saponification grade is 1-2.

[0011] Preferably, in step (4), the extraction process comprises: mixing the P204 extracted organic phase with the nickel-cobalt extract to perform nickel-cobalt co-extraction, the volume ratio of the P204 extracted organic phase to the nickel-cobalt extract is 1:1-5, and the extraction stage is 9-11.

[0012] Preferably, in step (5), the organic phase extracted by P507 and C272 is obtained by mixing P507, C272 and a diluent and then saponifying them with alkali solution; the volume ratio of C272, P507 and the diluent is 0.25:0.75:2.5-4; the diluent is one or more of sulfonated kerosene and light white oil; the saponification rate is 10-40%, and the saponification grade is 1-2.

[0013] Preferably, in step (5), the extraction process comprises: extracting the organic phase extracted by P507 and C272 in a volume ratio of 1:1-5 with the nickel-cobalt raffinate to obtain a cobalt-loaded organic phase 1 and a nickel raffinate; Washing the cobalt-loaded organic phase 1 with a washing liquid to obtain the washed cobalt-loaded organic phase 1 and washing water; Using a stripping solution to strip the washed cobalt-loaded organic phase 1 to obtain a cobalt raffinate; The washing liquid is one or more of nitric acid, sulfuric acid and hydrochloric acid solutions, and the concentration is 1-2N; the volume ratio of the cobalt-loaded organic phase 1 to the washing liquid is 1:0.5-1; the volume ratio of the washed cobalt-loaded organic phase 1 to the stripping liquid is 1:0.1-0.5; the stripping liquid is one or more of nitric acid, sulfuric acid and hydrochloric acid solutions, and the concentration is 5-6.5N.

[0014] Preferably, in step (6), the organic phase extracted with P507 is obtained by mixing P507 and a diluent and then saponifying them with alkali solution; the volume ratio of P507 to the diluent is 1:2.5-4; the diluent is one or more of sulfonated kerosene and light white oil; the saponification rate is 10-40%, and the saponification grade is 1-2.

[0015] Preferably, in step (6), the extraction process comprises: extracting the P507 extracted organic phase and the cobalt raffinate to obtain a cobalt-loaded organic phase II; The cobalt-loaded organic phase II is washed with a washing liquid to obtain a cobalt-rich organic phase and washing water; The cobalt-rich organic phase is stripped using a stripping solution to obtain a high-purity cobalt solution; Among them, the volume ratio of the P507 extraction organic phase to the cobalt raffinate is 1-5:1, and the extraction level is 9-11; the volume ratio of the cobalt-loaded organic phase II and the washing liquid is 1:0.5-1, and the washing level is 8-11; the volume ratio of the cobalt-rich organic phase to the stripping liquid is 1:0.1-0.5, and the stripping level is 9-12; the washing liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solution, and the concentration is 1-2N; the stripping liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solution, and the concentration is 5-6.5N.

[0016] The beneficial effects of the present invention are: The invention realizes the extraction and separation of nickel and cobalt by sequentially performing acid leaching, alkaline precipitation and impurity removal, P204 extraction, P507 and C272 synergistic extraction and P507 extraction on a nickel raw material associated with cobalt. The process flow is short and the production cost is low. The obtained nickel solution contains about 80-120 g / L of nickel, less than 5 mg / L of cobalt and magnesium, and less than 0.1 mg / L of copper, manganese, calcium and zinc. The obtained cobalt solution contains about 150-160 g / L of cobalt, less than 2 mg / L of nickel, magnesium and sodium, and less than 0.1 mg / L of copper, manganese, calcium, zinc, chromium and cadmium. The nickel solution and the cobalt solution can be refined simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings of the embodiment are briefly introduced below.

[0018] Figure 1 The present invention is a schematic flow chart of a method for preparing a high-purity cobalt solution from a nickel raw material and associated cobalt. DETAILED DESCRIPTION

[0019] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1 The embodiment of the present invention provides a method for preparing a high-purity cobalt solution from a nickel raw material and associated cobalt, comprising the following steps: (1) Slurrying: The nickel raw material with associated cobalt is mixed with pickling water and / or tap water at a solid-liquid ratio of 1:1-1.5 to obtain a slurry.

[0021] (2) Acid leaching: The pH of the pulped ore is adjusted to 1.5-2.0 using an acid solution, and the mixture is reacted at a temperature of 60-80°C for 2-3 hours to obtain an acid leaching slurry; wherein the acid solution is one or more of a sulfuric acid solution, a hydrochloric acid solution, and a nitric acid solution.

[0022] (3) Adjustment and impurity removal: Use alkaline slurry to adjust the pH of the acid leaching slurry to 5.2-5.5, react at 60-80℃ for 20-40min, and obtain nickel-cobalt extract and filter residue after solid-liquid separation; the alkaline slurry includes one or more of nickel-cobalt hydroxide slurry and lime milk. Alkaline slurry adjustment removes iron, aluminum, chromium and scandium in the acid leaching slurry.

[0023] (4) Extraction and impurity removal: P204 and diluent are mixed at a volume ratio of 1:2.5-4, and then saponified with alkali solution to obtain P204 extracted organic phase; the diluent is one or more of sulfonated kerosene and light white oil; the alkali solution includes one or more of sodium hydroxide and ammonia water, and the concentration of the alkali solution is preferably 30-32%, the saponification rate is 10-40%, and the saponification level is 1-2. The P204 extracted organic phase is mixed with the nickel-cobalt extract at a volume ratio of 1:1-5 for nickel-cobalt co-extraction, and the extraction level is 9-11, to obtain nickel-cobalt raffinate and an organic phase loaded with impurities such as copper, manganese, calcium, and zinc.

[0024] (5) Nickel and cobalt separation: C272, P507 and diluent are mixed in a volume ratio of 0.25:0.75:2.5-4, and then saponified with alkali solution to obtain a synergistic extraction organic phase. The diluent is one or more of sulfonated kerosene and light white oil; the alkali solution includes one or more of sodium hydroxide and ammonia water. The concentration of the alkali solution is preferably 30-32%, the saponification rate is 10-40%, and the saponification level is 1-2. The organic phase extracted synergistically with P507 and C272 is mixed with the nickel-cobalt raffinate at a volume ratio of 1:1-5 for extraction to obtain a cobalt-loaded organic phase 1 and a nickel raffinate; the cobalt-loaded organic phase 1 is washed with a washing liquid to obtain a washed cobalt-loaded organic phase 1 and washing water; the washed cobalt-loaded organic phase 1 is stripped with a stripping liquid to obtain a cobalt raffinate; wherein the washing liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solution, and the concentration is 1-2N; the volume ratio of the cobalt-loaded organic phase 1 to the washing liquid is 1:0.5-1; the volume ratio of the washed cobalt-loaded organic phase 1 to the stripping liquid is 1:0.1-0.5; the stripping liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solution, and the concentration is 5-6.5N.

[0025] (6) Refining and enrichment: P507 and a diluent are mixed in a volume ratio of 1:2.5-4, and then saponified with alkali solution to obtain a P507 extraction organic phase; the diluent is one or more of sulfonated kerosene and light white oil; the alkali solution includes one or more of sodium hydroxide and ammonia water, and the concentration of the alkali solution is preferably 30-32%, the saponification rate is 10-40%, and the saponification level is 1-2. The P507 extracted organic phase and the cobalt raffinate are mixed and extracted in a volume ratio of 1-5:1, and the extraction level is 9-11 to obtain a cobalt-loaded organic phase II; the cobalt-loaded organic phase II is washed with a washing liquid to obtain a cobalt-rich organic phase and washing water; the cobalt-rich organic phase is stripped with a stripping liquid to obtain a high-purity cobalt solution; wherein, the volume ratio of the cobalt-loaded organic phase II to the washing liquid is 1:0.5-1, and the washing level is 8-11; the volume ratio of the cobalt-rich organic phase to the stripping liquid is 1:0.1-0.5, and the stripping level is 9-12; the washing liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solutions, and the concentration is 1-2N; the stripping liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solutions, and the concentration is 5-6.5N.

[0026] In some preferred embodiments, the nickel raw material associated with cobalt in step (1) is a nickel-cobalt intermediate obtained by hydrometallurgy of laterite nickel ore, which contains 1-2% cobalt, 15-22% nickel, 1-3% manganese, 0.5-1% magnesium, and the remainder is water and other impurities.

[0027] In some preferred embodiments, step (3) further comprises countercurrent washing of the filter residue obtained after solid-liquid separation, specifically comprising: countercurrent washing of the filter residue by primary acid washing and tertiary water washing to obtain acid washing water, washing water of each level and filter residue discharged externally, landfilling the filter residue after washing, and recycling the acid washing water to step (1) slurrying or step (2) acid leaching as bottom water; preferably, the acid washing process is: the acid washing pH is 0.8-1.0, the acid washing temperature is 60-80°C, the acid washing time is 2-4 hours, the acid washing solid-liquid ratio is 1:1-2, after the acid washing is completed, the slurry pH is adjusted to between 1.5-2.0 with lime milk, and then the solid-liquid separation is performed to obtain the acid washing residue and the acid washing water, and the acid washing water is returned to the slurrying and leaching process. The water washing process is: the water washing solid-liquid ratio is 1:1-2, the water washing time is 1-2 hours, and the water washing temperature is 60-80°C.

[0028] In some preferred embodiments, step (4) further comprises using the nickel-cobalt raffinate to perform a soap-removal treatment on the saponified P204 extracted organic phase, wherein the volume ratio of the saponified P204 extracted organic phase to the nickel-cobalt raffinate is 1-10:1, and the soap-removal level is 5-7.

[0029] In some preferred embodiments, step (4) further comprises washing and stripping the impurity-loaded extracted organic phase obtained after the extraction treatment, and removing the impurity ions such as copper, manganese, calcium, and zinc loaded in the organic phase, so as to recycle the organic phase. The washing is performed by using one or more of nitric acid, sulfuric acid, and hydrochloric acid solutions with a concentration of 1-2N, the washing OA ratio is 1:0.5-1, the washing stage is 8-11, and the washing water is incorporated into the extraction section. Stripping is performed by using one or more of nitric acid, sulfuric acid, and hydrochloric acid solutions with a concentration of 5-6.5N, the stripping OA ratio is 1:0.1-0.5, and the stripping stage is 9-12.

[0030] In some preferred embodiments, the nickel raffinate obtained in step (5) is at least one of refined nickel sulfate, refined nickel chloride or refined nickel nitrate; step (5) also includes using the nickel raffinate as a soap transfer liquid to perform soap transfer treatment on the saponified synergistic extraction organic phase, wherein the volume ratio of the saponified synergistic extraction organic phase to the nickel raffinate is 1-10:1, and the soap transfer level is 5-7.

[0031] In some preferred embodiments, step (6) further comprises using a high-purity cobalt solution as a soap-transfer solution to perform soap-transfer treatment on the saponified P507 extract organic phase, wherein the volume ratio of the saponified P507 extract organic phase to the high-purity cobalt solution is 1-10:1, and the soap-transfer level is 5-7.

[0032] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below.

[0033] The nickel raw material of associated cobalt in the following embodiments is nickel cobalt hydroxide, an intermediate product of nickel cobalt obtained when nickel and cobalt are extracted by hydrometallurgical extraction of laterite nickel ore, which contains 1.8% cobalt, 20% nickel, 2.5% manganese, 0.7% magnesium, and other impurities and water.

[0034] Example 1 (1) Take nickel raw materials with associated cobalt and use acid washing water as bottom water for slurrying, with a slurrying solid-liquid ratio of 1:1 to obtain slurry.

[0035] (2) Take a portion of the pulped slurry and adjust its pH to 2.0 with sulfuric acid. After the pH stabilizes, leaching is performed for 2 hours at a leaching temperature of 70°C to obtain an acid leaching slurry.

[0036] (3) Take part of the pulped ore pulp and use it to adjust the pH of the acid leaching slurry to 5.5. After the pH stabilizes, continue to react for 30 minutes at a reaction temperature of 70°C. Solid-liquid separation is performed to obtain nickel-cobalt extract and filter residue. Use slag washing water to slurry the filter residue, the slurry solid-liquid ratio is 1:1, the acid washing pH is 1.0, the acid washing time is 2 hours, and the acid washing temperature is 70°C. After the acid washing is completed, use lime milk to adjust the pH to about 1.5, and solid-liquid separation is performed to obtain acid washing water and acid washing filter residue. The acid washing filter residue is subjected to three-stage countercurrent washing, the solid-liquid ratio of each stage is 1:2, the washing time of each stage is 2 hours, and the washing temperature of each stage is 70°C. After solid-liquid separation, each level of washing water and external slag are obtained.

[0037] (4) P204 and light white oil are mixed in a volume ratio of 1:3, and then saponified with 30% sodium hydroxide. The saponification rate is controlled at 24%, and the saponification level is 2, to obtain the P204 extraction organic phase; soap conversion: the OA ratio of the soap conversion section is 5:1, the soap conversion level is 7, and the nickel-cobalt extract is used as the soap conversion liquid. Extraction: The OA ratio of the extraction section is 1:3, the extraction level is 10, and the nickel-cobalt extract is obtained. Washing: The OA ratio of the washing section is 1:0.75, the washing section is 9 levels, the washing acid is 1.2N sulfuric acid, and the washing water is incorporated into the extraction section. Stripping: The OA ratio of stripping is 1:0.3, the stripping section is 12 levels, and the stripping liquid is 6N hydrochloric acid. Impurities such as copper, manganese, calcium, and zinc loaded on the organic phase are removed with the stripping waste liquid. The nickel-cobalt raffinate contains 120g / L nickel, 12g / L cobalt, 10g / L magnesium, and 1.2mg / L copper, manganese, calcium and zinc; the stripping waste liquid contains 30mg / L nickel and 150mg / L cobalt.

[0038] (5) C272, P507 and light white oil were mixed in a volume ratio of 0.25:0.75:4, and then saponified with 30% sodium hydroxide. The saponification rate was controlled at 20%, and the saponification level was 2, to obtain a synergistic extraction organic phase. Soap transfer: The OA ratio of the soap transfer section was 5:1, the soap transfer section was 6 levels, and the nickel raffinate was used as the soap transfer liquid. Extraction: The nickel-cobalt raffinate was extracted, the OA ratio of the extraction section was 1:3, the extraction section was 10 levels, and the cobalt-loaded organic phase 1 and the nickel raffinate were obtained. The obtained nickel raffinate was the refined nickel solution. Washing: The OA ratio of the washing section was 1:0.75, the washing section was 9 levels, the washing acid was 1.2N sulfuric acid, and the washing water was merged into the extraction section. Stripping: The OA ratio of the stripping was 1:0.3, the stripping section was 12 levels, the stripping acid was 6N hydrochloric acid, and the stripping solution was open-circuited to obtain a cobalt raffinate. The cobalt raffinate contained 0.8 g / L nickel.

[0039] (6) P507 and light white oil are mixed in a volume ratio of 1:4, and then saponified with 30% sodium hydroxide. The saponification rate is controlled at 30%, and the saponification level is 2 to obtain the extracted organic phase. Soap transfer: The OA ratio of the soap transfer section is 5:1, the soap transfer section is 7 levels, and a high-purity cobalt solution is used as the soap transfer liquid. Extraction: The OA ratio of the extraction section is 3:1, the extraction section is 10 levels, and the cobalt-loaded organic phase II and wastewater are obtained; washing: The OA ratio of the washing section is 1:0.75, the washing section is 9 levels, the washing acid is 1.2N hydrochloric acid, and the washing water is incorporated into the extraction section. Stripping: The OA ratio of stripping is 1:0.2, the stripping section is 12 levels, the stripping acid is 5.5N hydrochloric acid, and the stripping liquid is open-circuited to obtain a cobalt chloride solution.

[0040] Example 2 (1) Take the nickel raw material with associated cobalt and use acid washing water as bottom water for slurrying, with the slurrying solid-liquid ratio of 1:1.5 to obtain slurry.

[0041] (2) Take the pulped ore slurry and adjust its pH to 1.5 with sulfuric acid. After the pH stabilizes, leaching is carried out for 2 hours at a leaching temperature of 70°C to obtain an acid leaching slurry.

[0042] (3) Take lime milk and use it to adjust the pH of the acid leaching slurry to 5.2. After the pH stabilizes, continue to react for 30 minutes at a reaction temperature of 70°C. Solid-liquid separation is performed to obtain nickel-cobalt extract and filter residue. Use slag washing water to slurry the filter residue, the slurry solid-liquid ratio is 1:1, the acid washing pH is 1.0, the acid washing time is 2 hours, and the acid washing temperature is 70°C. After the acid washing is completed, use lime milk to adjust the pH to about 1.5, and solid-liquid separation is performed to obtain acid washing water and acid washing filter residue. The acid washing filter residue is subjected to three-stage countercurrent washing, the solid-liquid ratio of each stage is 1:2, the washing time of each stage is 2 hours, and the washing temperature of each stage is 70°C. After solid-liquid separation, each level of washing water and external slag are obtained.

[0043] (4) P204 and light white oil are mixed in a volume ratio of 1:4, and then saponified with 30% sodium hydroxide. The saponification rate is controlled at 26%, and the saponification level is 2, to obtain the P204 extraction organic phase; soap conversion: the OA ratio of the soap conversion section is 10:1, the soap conversion level is 5, and the nickel-cobalt extract is used as the soap conversion liquid. Extraction: The OA ratio of the extraction section is 1:5, the extraction level is 10, and the nickel-cobalt extract is obtained. Washing: The OA ratio of the washing section is 1:0.5, the washing section is 9, the washing acid is 1N sulfuric acid, and the washing water is incorporated into the extraction section. Stripping: The OA ratio of stripping is 1:0.5, the stripping section is 12, and the stripping liquid is 6.5N hydrochloric acid. Impurities such as copper, manganese, calcium, and zinc loaded on the organic phase are removed with the stripping waste liquid. The nickel-cobalt raffinate contains 100g / L nickel, 10g / L cobalt, 12g / L magnesium, and 1.5mg / L copper, manganese, calcium and zinc; the stripping waste liquid contains 20mg / L nickel and 200mg / L cobalt.

[0044] (5) C272, P507 and light white oil were mixed in a volume ratio of 0.25:0.75:3, and then saponified with 30% sodium hydroxide. The saponification rate was controlled at 22%, and the saponification level was 2, to obtain a synergistic extraction organic phase. Soap transfer: The OA ratio of the soap transfer section was 8:1, the soap transfer section was 6 levels, and the nickel raffinate was used as the soap transfer liquid. Extraction: The nickel-cobalt raffinate was extracted, the OA ratio of the extraction section was 1:5, the extraction section was 10 levels, and the cobalt-loaded organic phase 1 and the nickel raffinate were obtained. The obtained nickel raffinate was the refined nickel solution. Washing: The OA ratio of the washing section was 1:0.5, the washing section was 9 levels, the washing acid was 1N sulfuric acid, and the washing water was merged into the extraction section. Stripping: The OA ratio of the stripping was 1:0.5, the stripping section was 12 levels, the stripping acid was 6N hydrochloric acid, and the stripping solution was open-circuited to obtain a cobalt raffinate. The cobalt raffinate contained 1.5 g / L nickel.

[0045] (6) P507 and light white oil are mixed in a volume ratio of 1:4, and then saponified with 30% sodium hydroxide. The saponification rate is controlled at 30%, and the saponification level is 2 to obtain the extracted organic phase. Soap transfer: The OA ratio of the soap transfer section is 5:1, the soap transfer section is 7 levels, and a high-purity cobalt solution is used as the soap transfer liquid. Extraction: The OA ratio of the extraction section is 5:1, the extraction section is 10 levels, and the cobalt-loaded organic phase II and wastewater are obtained; washing: The OA ratio of the washing section is 1:0.75, the washing section is 9 levels, the washing acid is 1.2N sulfuric acid, and the washing water is incorporated into the extraction section. Stripping: The OA ratio of stripping is 1:0.5, the stripping section is 12 levels, the stripping acid is 6.5N sulfuric acid, and the stripping liquid is open-circuited to obtain a cobalt sulfate solution.

[0046] Example 3 (1) Take nickel raw materials with associated cobalt and use tap water as bottom water for slurrying, with the slurrying solid-liquid ratio being 1:1.2 to obtain slurry.

[0047] (2) Take the pulped ore slurry and adjust its pH to 2.0 with sulfuric acid. After the pH stabilizes, leaching is carried out for 2 hours at a leaching temperature of 70°C to obtain an acid leaching slurry.

[0048] (3) Take lime milk and use it to adjust the pH of the acid leaching slurry to 5.3. After the pH stabilizes, continue to react for 30 minutes at a reaction temperature of 70°C. Solid-liquid separation is performed to obtain nickel-cobalt extract and filter residue. Use slag washing water to slurry the filter residue, the slurry solid-liquid ratio is 1:1, the acid washing pH is 1.0, the acid washing time is 2 hours, and the acid washing temperature is 70°C. After the acid washing is completed, use lime milk to adjust the pH to about 1.5, and solid-liquid separation is performed to obtain acid washing water and acid washing filter residue. The acid washing filter residue is subjected to three-stage countercurrent washing, the solid-liquid ratio of each stage is 1:2, the washing time of each stage is 2 hours, and the washing temperature of each stage is 70°C. After solid-liquid separation, each level of washing water and external slag are obtained.

[0049] (4) P204 and light white oil are mixed in a volume ratio of 1:2.5, and then saponified with 30% sodium hydroxide. The saponification rate is controlled at 25%, and the saponification level is 2, to obtain the P204 extraction organic phase; soap conversion: the OA ratio of the soap conversion section is 8:1, the soap conversion level is 5, and the nickel-cobalt extract is used as the soap conversion liquid. Extraction: The OA ratio of the extraction section is 1:1, the extraction level is 10, and the nickel-cobalt extract is obtained. Washing: The OA ratio of the washing section is 1:0.6, the washing section is 9 levels, the washing acid is 2N sulfuric acid, and the washing water is incorporated into the extraction section. Stripping: The OA ratio of stripping is 1:0.2, the stripping section is 12 levels, and the stripping liquid is 5N hydrochloric acid. Impurities such as copper, manganese, calcium, and zinc loaded on the organic phase are removed with the stripping waste liquid. The nickel-cobalt extract residue contains 80g / L nickel, 6g / L cobalt, 6g / L magnesium, and 1.0mg / L copper, manganese, calcium and zinc; the stripping waste liquid contains 40mg / L nickel and 220mg / L cobalt.

[0050] (5) C272, P507 and light white oil were mixed in a volume ratio of 0.25:0.75:2.5, and then saponified with 30% sodium hydroxide. The saponification rate was controlled at 22%, and the saponification level was 2, to obtain a synergistic extraction organic phase. Soap transfer: The OA ratio of the soap transfer section was 10:1, the soap transfer section was 6 levels, and the nickel raffinate was used as the soap transfer liquid. Extraction: The nickel-cobalt raffinate was extracted, the OA ratio of the extraction section was 1:5, the extraction section was 10 levels, and the cobalt-loaded organic phase 1 and the nickel raffinate were obtained. The obtained nickel raffinate was the refined nickel solution. Washing: The OA ratio of the washing section was 1:0.8, the washing section was 9 levels, the washing acid was 1N sulfuric acid, and the washing water was merged into the extraction section. Stripping: The OA ratio of the stripping was 1:0.2, the stripping section was 12 levels, the stripping acid was 6N hydrochloric acid, and the stripping solution was open-circuited to obtain a cobalt raffinate. The cobalt raffinate contained 0.5 g / L nickel.

[0051] (6) P507 and light white oil are mixed in a volume ratio of 1:2.5, and then saponified with 30% sodium hydroxide. The saponification rate is controlled at 30%, and the saponification level is 2 to obtain the extracted organic phase. Soap transfer: The OA ratio of the soap transfer section is 8:1, the soap transfer section is 7 levels, and a high-purity cobalt solution is used as the soap transfer liquid. Extraction: The OA ratio of the extraction section is 4:1, the extraction section is 10 levels, and the cobalt-loaded organic phase II and wastewater are obtained; washing: The OA ratio of the washing section is 1:0.5, the washing section is 9 levels, the washing acid is 2N hydrochloric acid, and the washing water is merged into the extraction section. Stripping: The OA ratio of the stripping is 1:0.2, the stripping section is 12 levels, the stripping acid is 6N nitric acid, and the stripping liquid is open-circuited to obtain a cobalt nitrate solution.

[0052] The main components of the nickel solution and the cobalt solution obtained in Examples 1 to 3 were tested respectively, and the results are shown in Table 1.

[0053] Table 1

[0054] It can be seen from the above table that the method for preparing a high-purity cobalt solution from a nickel raw material with associated cobalt provided by the present invention only requires acid leaching, alkali precipitation, P204 extraction, P507, C272 synergistic extraction, and P507 extraction to achieve the extraction and separation of nickel and cobalt, with a short process flow and low production cost. The obtained nickel solution contains about 80-120 g / L of nickel, less than 5 mg / L of cobalt and magnesium, and less than 0.1 mg / L of copper, manganese, calcium, and zinc; the obtained cobalt solution contains about 150-160 g / L of cobalt, less than 2 mg / L of nickel, magnesium, and sodium, and less than 0.1 mg / L of copper, manganese, calcium, zinc, chromium, and cadmium, and can simultaneously achieve the refining of the nickel solution and the cobalt solution.

[0055] It should be noted that the above embodiments all belong to the same inventive concept, and the description of each embodiment has its own focus. For details not described in individual embodiments, reference may be made to the description in other embodiments.

[0056] The above-mentioned embodiments only express the implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material, characterized in that: The following steps are involved: (1) Slurrying the nickel raw material with associated cobalt to obtain pulped ore pulp; (2) adjusting the pH of the pulped slurry to 1.5-2.0 using an acid solution, and performing an acid leaching reaction to obtain an acid leaching slurry; (3) adjusting the pH of the acid leaching slurry to 5.2-5.5 using an alkaline slurry, and obtaining a nickel-cobalt extract and a filter residue after precipitation reaction and solid-liquid separation; (4) extracting the nickel-cobalt extract with an organic phase extracted with P204 to obtain a nickel-cobalt raffinate; (5) extracting the nickel-cobalt raffinate using P507 and C272 as a synergistic extraction organic phase to obtain a cobalt-loaded organic phase 1, and stripping the cobalt-loaded organic phase 1 to obtain a cobalt raffinate; (6) extracting the cobalt raffinate with a P507 organic phase to obtain a cobalt-loaded organic phase II, and stripping the cobalt-loaded organic phase II to obtain a high-purity cobalt solution.

2. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (1), the nickel raw material with associated cobalt includes nickel cobalt hydroxide; the solution used for pulping is one or more of pickling water and tap water; and the solid-liquid ratio of the pulping slurry is 1:1-1.

5.

3. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (2), the acid solution is one or more of a sulfuric acid solution, a hydrochloric acid solution, and a nitric acid solution; the temperature of the acid leaching reaction is 60-80° C., and the reaction time is 2-3 hours.

4. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (3), the alkaline slurry includes one or more of nickel cobalt hydroxide slurry and lime milk; the temperature of the precipitation reaction is 60-80°C, and the reaction time is 20-40min.

5. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (4), the P204 extracted organic phase is obtained by mixing P204 and a diluent and then saponifying with alkali solution; the volume ratio of P204 to the diluent is 1:2.5-4; the diluent is one or more of sulfonated kerosene and light white oil; the saponification rate of the saponification is 10-40%, and the saponification grade is 1-2.

6. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (4), the extraction process includes: mixing the P204 extracted organic phase with the nickel-cobalt extract to perform nickel-cobalt co-extraction, the volume ratio of the P204 extracted organic phase to the nickel-cobalt extract is 1:1-5, and the extraction level is 9-11.

7. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (5), the organic phase extracted by synergistic extraction of P507 and C272 is obtained by mixing P507, C272 and a diluent and then saponifying the mixture using alkali solution; the volume ratio of C272, P507 and the diluent is 0.25:0.75:2.5-4; the diluent is one or more of sulfonated kerosene and light white oil; the saponification rate of the saponification is 10-40%, and the saponification grade is 1-2.

8. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (5), the extraction process includes: The P507 and C272 synergistically extracted organic phase is mixed with the nickel-cobalt raffinate at a volume ratio of 1:1-5 for extraction to obtain a cobalt-loaded organic phase 1 and a nickel raffinate; Washing the cobalt-loaded organic phase 1 with a washing liquid to obtain a washed cobalt-loaded organic phase 1 and washing water; Using a stripping solution to strip the washed cobalt-loaded organic phase 1 to obtain a cobalt raffinate; Wherein, the washing liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solutions, and the concentration is 1-2N; the volume ratio of the cobalt-loaded organic phase 1 to the washing liquid is 1:0.5-1; the volume ratio of the washed cobalt-loaded organic phase 1 to the stripping solution is 1:0.1-0.5; the stripping solution is one or more of nitric acid, sulfuric acid, and hydrochloric acid solutions, and the concentration is 5-6.5N.

9. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (6), the P507 extraction organic phase is obtained by mixing P507 and a diluent and then saponifying with alkali solution; the volume ratio of P507 to the diluent is 1:2.5-4; the diluent is one or more of sulfonated kerosene and light white oil; the saponification rate of the saponification is 10-40%, and the saponification grade is 1-2.

10. The method for preparing a high-purity cobalt solution from cobalt associated with a nickel raw material according to claim 1, characterized in that: In step (6), the extraction process comprises: The P507 extracted organic phase and the cobalt raffinate are mixed and extracted to obtain a cobalt-loaded organic phase II; Washing the cobalt-loaded organic phase 2 with a washing liquid to obtain a cobalt-rich organic phase and washing water; stripping the cobalt-rich organic phase with a stripping solution to obtain a high-purity cobalt solution; Among them, the volume ratio of the P507 extraction organic phase to the cobalt raffinate is 1-5:1, and the extraction level is 9-11; the volume ratio of the cobalt-loaded organic phase II and the washing liquid is 1:0.5-1, and the washing level is 8-11; the volume ratio of the cobalt-rich organic phase to the stripping liquid is 1:0.1-0.5, and the stripping level is 9-12; the washing liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solution, and the concentration is 1-2N; the stripping liquid is one or more of nitric acid, sulfuric acid, and hydrochloric acid solution, and the concentration is 5-6.5N.

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