Method for efficiently separating low-concentration copper and manganese in cobalt nickel sulfate solution

Abstract

The invention discloses a method for efficiently separating low-concentration copper and manganese in a nickel cobalt sulfate solution. The method comprises the following steps: (1) adding liquid caustic soda into a P204 organic solution in an independent saponification tank for saponification; (2) organically pumping the saponified P204 into a reaction kettle, continuously stirring, adding a cobalt nickel sulfate solution into the reaction kettle, and carrying out full extraction reaction; and (3) pumping the reacted solution into a centrifugal separation device to realize separation of an organic phase and a water phase, enabling the water phase to enter a P507 extraction process to be further extracted to prepare a cobalt salt solution, and enabling the organic phase to enter another set of countercurrent multi-stage series P204 extraction box to be organically used as soap. According to the method, the reaction kettle is used for replacing continuous counter-current extraction equipment for preparation and full extraction, the nickel-cobalt sulfate solution with low copper and manganese content in an original cobalt production system is independently treated, the copper and manganese separation efficiency of the nickel-cobalt sulfate solution is effectively improved, and chemical reagent consumption caused by repeated cobalt washing in the extraction process is reduced; and the production organization efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrometallurgy, and in particular relates to a method for efficiently separating low-concentration copper and manganese in nickel-cobalt sulfate liquid. Background Art

[0002] At present, there are many kinds of cobalt-containing raw materials, and cobalt hydrometallurgical enterprises are often faced with the situation of dealing with different types of cobalt-containing raw materials. P204 extractant is often used to separate impurities such as copper, manganese, and calcium from cobalt-containing solutions. Faced with nickel cobalt sulfate solutions with different impurity contents, cobalt smelting enterprises often need to set up different production lines. Moreover, due to the long cobalt smelting process, they often face problems such as large consumption of chemical reagents and difficulties in production organization. The traditional P204 extraction process often uses multi-stage countercurrent extraction equipment to treat impurities in cobalt sulfate solution. The P204 extraction facility is often composed of a saponification section, an extraction section, a cobalt washing section, a copper washing section, and an iron washing section. P204 is an organic phosphoric acid extractant. Its extraction ability for different metals in a sulfate system is in the order of Fe:Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe :Fe 3+ >Zn 2+ >Cu 2+ ≈Mn 2+ ≈Ca 2+ >Co 2+ >Mg 2+ >Ni 2+ Therefore, Fe, Zn, Cu, Mn, Ca, etc. that are ahead of Co ions will be extracted first. At the same time, due to the high concentration of cobalt ions, cobalt extraction reaction will inevitably occur during the extraction process. Therefore, it is necessary to set up multi-stage cobalt washing sections for cobalt washing. There is also the possibility of elution of copper and manganese impurities during the washing process. Therefore, it is necessary to set up 8-10 levels of cobalt washing sections, which undoubtedly causes a waste of production resources. Summary of the invention

[0003] The present invention aims to disclose a method for separating low-concentration copper and manganese from nickel-cobalt sulfate solution, so as to reduce production costs and more economically purify nickel-cobalt metal from nickel-cobalt sulfate solution.

[0004] To this end, the present invention adopts the following technical solutions: A method for efficiently separating low-concentration copper and manganese in nickel cobalt sulfate solution, characterized in that it comprises the following steps: (1) Add liquid alkali to the P204 organic in a separate saponification tank for saponification; The saponification rate of P204 saponification process can be adjusted according to the copper and manganese content in the nickel cobalt sulfate solution, preferably 25-35%; (2) Pump the saponified P204 organically into the reactor, continue stirring and add cobalt nickel sulfate solution into the reactor to carry out a full extraction reaction. The extraction temperature is 45-55°C and the reaction time is 10-20 minutes; The element contents of the nickel cobalt sulfate solution are as follows: 20-60 g / L of cobalt, 20-60 g / L of nickel, 0.01-1.5 g / L of manganese, and 0.1-3.5 g / L of manganese; (3) The solution after the reaction is pumped into a centrifugal separation device to separate the organic phase from the aqueous phase. The aqueous phase enters the P507 extraction process for further extraction to prepare a cobalt salt solution, and the organic phase enters another set of countercurrent multi-stage series P204 extraction boxes to be used as post-soap organic phase; In step 3), the element contents in the organic phase are as follows: Co 2.0~4.0g / L, Ni 5.0~7.0g / L, Cu 0.1~1.0g / L, Mn 1.5~4.5g / L; the element contents in the aqueous phase are as follows: Co 50~55g / L, Ni 14~17g / L, Cu≤0.0005g / L, Mn≤0.0005g / L.

[0005] Compared with the prior art, the present invention has the following beneficial effects: 1. In the present invention, a reactor and other equipment are used instead of a multi-stage extraction equipment. After the solution is fully extracted in the reactor, a centrifuge is used to separate the aqueous phase and the organic phase. The output aqueous phase has a low content of copper and manganese impurities and can directly enter the P507 nickel-cobalt separation process, thereby effectively avoiding the consumption of hydrochloric acid in the cobalt washing process of the traditional process.

[0006] 2. The organic phase produced after centrifugal separation is an organic phase loaded with nickel and cobalt, which has the ability to extract impurity metal ions such as iron, copper, manganese, and calcium. Therefore, it can be used in another multi-stage countercurrent extraction production line for treating nickel cobalt sulfate solution with high copper and manganese content, which can effectively reduce the consumption of liquid alkali in the saponification process.

[0007] 3. The present invention can organize the production process to a greater extent according to the copper and manganese impurity content of the cobalt raw material, effectively reducing equipment investment and greatly improving production organization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0009] The present invention is further explained below with reference to specific embodiments.

[0010] The nickel cobalt sulfate solution used in the following embodiments comes from high manganese black powder of waste batteries, and the treatment process is as follows: the high manganese black powder and concentrated sulfuric acid are fully mixed at a material acid volume ratio of 1:1-1:1.2, and then the mixed acid material is transferred to a muffle furnace and fully calcined at 400-550°C for 2h; the calcined black powder is dissolved with alkaline wastewater at a liquid-to-solid ratio of 3:1, and an appropriate amount of liquid alkali is added during the process to control the end point pH to 8.0-8.5, and the dissolved solution is filtered; the filter residue is leached using a conventional two-stage sulfuric acid leaching process, and the pH of the leaching solution is controlled to be 1.5-2.0 during the leaching process. The leaching solution is supplied to the extraction process after iron removal.

[0011] Example 1 1. The element contents of the nickel cobalt sulfate solution used in this embodiment are: Co55.6g / L, Ni23.6g / L, Cu0.25g / L, Mn2.1g / L. The organic saponification rate of P204 used is 30%.

[0012] 2. In this embodiment, the amount of organic matter entering the reactor is 15m³, and the amount of nickel cobalt sulfate solution is 12m³.

[0013] 3. The reaction temperature was kept below 52°C and the reaction time was 15 min.

[0014] 4. After stirring, the reaction solution was separated by a centrifuge, and the nickel, cobalt, copper and manganese content in the organic and aqueous phases were sampled and analyzed respectively.

[0015] 5. The element contents in the aqueous phase are as follows: Co53.6g / L, Ni16.2g / L, Cu0.0004g / L, Mn0.00045g / L; the element contents in the organic phase are as follows: Co3.22g / L, Ni5.48g / L, Cu0.82g / L, Mn1.66g / L.

[0016] 6. According to the analysis results, the copper and manganese contents in the aqueous phase after the extraction reaction met the index requirement of less than 0.0005g / L. After the organic matter after centrifugal separation was supplemented to the multi-stage countercurrent extraction process, there was no fluctuation in the production system.

[0017] 7. The process was operated continuously for 5 days according to the above steps. The consumption of cobalt hydrochloric acid per ton in the P204 process was reduced by 0.11t / tCo compared with the previous period, and the consumption of liquid alkali per ton was reduced by 0.16t / tCo compared with the previous period.

[0018] 8. The above experimental results show that by adopting the process described in this patent, the purpose of efficiently separating copper and manganese in nickel cobalt sulfate solution can be achieved. At the same time, the implementation of this measure will not cause quality abnormalities in the production process.

[0019] Example 2 1. The element contents of the nickel cobalt sulfate solution used in this embodiment are: Co52.6g / L, Ni20.8g / L, Cu0.45g / L, Mn3.1g / L. The organic saponification rate of P204 used is 35%.

[0020] 2. In this embodiment, the amount of organic matter entering the reactor is 15m³, and the amount of nickel cobalt sulfate solution is 15m³.

[0021] 3. The reaction temperature was kept below 52°C and the reaction time was 12 minutes.

[0022] 4. After stirring, the reaction solution was separated by a centrifuge, and the nickel, cobalt, copper and manganese content in the organic and aqueous phases were sampled and analyzed respectively.

[0023] 5. The element contents in the aqueous phase are as follows: Co50.2g / L, Ni14.9g / L, Cu0.0003g / L, Mn0.0004g / L; the element contents in the organic phase are as follows: Co2.35g / L, Ni6.1g / L, Cu0.45g / L, Mn3.08g / L.

[0024] 6. According to the analysis results, the copper and manganese contents in the aqueous phase after the extraction reaction met the index requirement of less than 0.0005g / L. After the organic matter after centrifugal separation was supplemented to the multi-stage countercurrent extraction process, there was no fluctuation in the production system.

[0025] 7. The process was operated continuously for 5 days according to the above steps. The consumption of cobalt hydrochloric acid per ton in the P204 process was reduced by 0.15t / tCo compared with the previous period, and the consumption of liquid alkali per ton was reduced by 0.2t / tCo compared with the previous period.

[0026] 6. The above experimental results show that by adopting the process described in this patent, the purpose of efficiently separating copper and manganese in nickel cobalt sulfate solution can be achieved. At the same time, the implementation of this measure will not cause quality abnormalities in the production process.

[0027] In summary, the present invention utilizes a reaction kettle instead of a multi-stage countercurrent extraction facility to complete the P204 extraction process, so that the solution after the reaction can directly meet the solution index requirements of the P507 nickel-cobalt separation process. After extraction, the organic phase is loaded with nickel and cobalt, so it can be added to the multi-stage countercurrent extraction and separation process for treating cobalt raw materials with high impurity content. Because the organic phase is already loaded with nickel and cobalt, it has the conditions for extracting copper and manganese, and thus can effectively reduce the consumption of liquid alkali required for saponification. This process mainly treats cobalt raw materials with low copper and manganese impurity content by coordinating multiple production lines, which can effectively reduce the consumption of hydrochloric acid liquid alkali in the extraction process and improve production efficiency.

Claims

1. A method for efficiently separating low-concentration copper and manganese in nickel cobalt sulfate solution, characterized in that: The following steps are involved: (1) Add liquid alkali to the P204 organic in a separate saponification tank for saponification, and control the saponification rate at 25%~35%; (2) Pump the saponified P204 organically into the reactor, continue stirring and add cobalt nickel sulfate solution into the reactor to carry out a full extraction reaction. The extraction temperature is 45-55°C and the reaction time is 10-20 minutes; (3) The solution after the reaction is pumped into a centrifugal separation device to separate the organic phase from the aqueous phase. The aqueous phase enters the P507 extraction process for further extraction to prepare a cobalt salt solution, and the organic phase enters another set of countercurrent multi-stage series P204 extraction boxes to be used as post-soap organic.

2. A method for efficiently separating low-concentration copper and manganese in nickel-cobalt sulfate solution as claimed in claim 1, characterized in that: In step 2), the element contents of the nickel cobalt sulfate solution are as follows: 20-60 g / L cobalt, 20-60 g / L nickel, 0.01-1.5 g / L manganese, and 0.1-3.5 g / L manganese.

3. A method for efficiently separating low-concentration copper and manganese in nickel-cobalt sulfate solution as claimed in claim 1, characterized in that: In step 3), the element contents in the organic phase are as follows: Co 2.0~4.0g / L, Ni 5.0~7.0g / L, Cu 0.1~1.0g / L, Mn 1.5~4.5g / L; the element contents in the aqueous phase are as follows: Co 50~55g / L, Ni 14~17g / L, Cu≤0.0005g / L, Mn≤0.0005g / L.

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