Method for improving the main component in nickel cobalt hydroxide intermediate product

Abstract

The present invention provides a method for improving the main components in a nickel-cobalt hydroxide intermediate product. The improvement method comprises: step S100, using an alkaline substance to perform a first activation on the nickel-cobalt hydroxide intermediate product slurry to obtain a first activated product slurry; step S200, adjusting the solid content of the first activated product slurry; step S300, using a reducing agent to perform a second activation on the first activated product slurry to obtain a second activated product slurry; step S400, adjusting the solid content of the second activated product slurry; step S500, adding the second activated product slurry to a nickel-cobalt solution for conversion reaction to obtain nickel-cobalt hydroxide and a converted liquid. The method of the present invention can significantly increase the total content of nickel and cobalt in nickel-cobalt hydroxide to a level of more than 50%. It solves the problem of high impurity content of magnesium, manganese and the like in the nickel-cobalt hydroxide intermediate product, high sulfate content, and the resulting increase in subsequent refining production costs.

Description

Technical Field

[0001] The invention relates to the technical field of nickel-cobalt hydrometallurgy, and in particular to a method for improving the main component in a nickel-cobalt hydroxide intermediate product. Background Art

[0002] At present, high-pressure leaching hydrometallurgy of limonite-type laterite nickel ore is one of the main processes for nickel metallurgy. The process flow of this method is: leaching - iron and aluminum removal - nickel and cobalt precipitation to obtain nickel cobalt hydroxide (MHP) intermediate product; this nickel cobalt hydroxide intermediate product is then acid dissolved - impurity removal, and extraction and separation of impurities and nickel and cobalt to obtain the final nickel cobalt product.

[0003] The inventors of the present application have realized that the above process method has the following problems: the content of impurities such as magnesium and manganese in the product is relatively high, about 1-5% and 5-8%, and the content of nickel and cobalt is relatively low, about 35-41% and 1-2%. At the same time, a large amount of basic sulfate is generated during the precipitation process, resulting in a high sulfate content and a low nickel and cobalt content. The presence of impurities leads to an increase in subsequent refining production costs. Therefore, it is of great significance to provide an efficient treatment method to solve the above problems.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for improving the main components in a nickel cobalt hydroxide intermediate product, so as to solve the problems in the prior art that the content of impurities such as magnesium and manganese and the content of sulfate in the nickel cobalt hydroxide intermediate product is relatively high, and the subsequent refining production cost is increased thereby.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a method for improving the main components in a nickel cobalt hydroxide intermediate product is provided, wherein the nickel cobalt hydroxide intermediate product comprises hydroxides and basic sulfates of nickel ions, cobalt ions, manganese ions and magnesium ions, and the improvement method comprises: step S100, using an alkaline substance to perform a first activation on the nickel cobalt hydroxide intermediate product slurry to obtain a first activated product slurry; step S200, adjusting the solid content of the first activated product slurry; step S300, using a reducing agent to perform a second activation on the first activated product slurry to obtain a second activated product slurry; step S400, adjusting the solid content of the second activated product slurry; step S500, adding the second activated product slurry to a nickel cobalt-containing solution for conversion reaction to obtain nickel cobalt hydroxide and a converted liquid.

[0007] Furthermore, in the above step S100, the solid content of the nickel cobalt hydroxide intermediate product slurry is 0.1% to 35%, preferably 5% to 20%.

[0008] Furthermore, in the above step S100, the nickel cobalt hydroxide intermediate product slurry is obtained by pre-treating the nickel cobalt hydroxide intermediate product, and the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide slurry or a nickel cobalt hydroxide filter cake.

[0009] Furthermore, in the above step S100, when the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide slurry, the nickel cobalt hydroxide slurry is concentrated or diluted to obtain a nickel cobalt hydroxide intermediate product slurry; when the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide filter cake, the nickel cobalt hydroxide filter cake is slurried to obtain a nickel cobalt hydroxide intermediate product slurry.

[0010] Furthermore, in the above step S100, the alkaline substance is selected from any one or more of sodium hydroxide, potassium hydroxide, and ammonium hydroxide.

[0011] Furthermore, in the above step S100, the temperature of the first activation is 25°C to 260°C, preferably 80°C to 150°C, and the time of the first activation is 0.1h to 10h, preferably 2h to 8h.

[0012] Furthermore, in the above step S100, the mass of the alkaline substance is 0.05% to 20% of the dry weight of the nickel cobalt hydroxide intermediate product slurry, preferably 0.5% to 5%.

[0013] Furthermore, in the above step S300, the reducing agent is selected from any one or more of sodium sulfite, potassium sulfite, ammonium sulfite, sodium pyrosulfite, potassium pyrosulfite, ammonium pyrosulfite and sulfur dioxide.

[0014] Furthermore, in the above step S300, the temperature of the second activation is 25°C to 260°C, preferably 80°C to 150°C, and the time of the second activation is 0.1h to 10h, preferably 2h to 8h.

[0015] Furthermore, in the above step S300, the amount of the substance derived from the sulfite group in the reducing agent is 0.1 to 5 times, preferably 0.2 to 1.5 times, the amount of the substance of the manganese ion in the nickel cobalt hydroxide intermediate product slurry.

[0016] Furthermore, in the above step S200, the solid content of the first activated product slurry is 0.1%~35%, preferably 5%~20%; the process of adjusting the solid content of the first activated product slurry includes: concentrating or diluting the first activated product slurry; or sequentially performing solid-liquid separation and slurrying treatment on the first activated product slurry.

[0017] Furthermore, in the above step S500, the temperature of the conversion reaction is 25°C~260°C, preferably 80~150°C, the time of the conversion reaction is 0.1h~10h, preferably 2h~8h; the liquid-to-solid ratio of the conversion reaction is 1~10:1, preferably 3~10:1.

[0018] Furthermore, in the above step S500, the nickel cobalt hydroxide intermediate product is obtained from the nickel-containing solution by a precipitation method, and the precipitation method is selected from any one of magnesium oxide precipitation method, magnesium hydroxide precipitation method, sodium hydroxide lithium precipitation method, potassium hydroxide lithium precipitation method, calcium oxide precipitation method and calcium hydroxide precipitation method.

[0019] Furthermore, in the above step S500, the nickel-containing solution includes a laterite nickel ore leaching system, and the laterite nickel ore leaching system is selected from any one or more of a laterite nickel ore sulfuric acid leaching solution, a laterite nickel ore hydrochloric acid leaching solution and a laterite nickel ore nitric acid leaching solution.

[0020] By applying the technical solution of the present application, the total content of nickel and cobalt in nickel cobalt hydroxide can be significantly increased to a level of more than 50% through the method of the present invention, while effectively reducing the content of impurities such as magnesium and manganese, and optimizing product quality. The reduction in impurity content reduces the complexity and cost of subsequent refining and separation processes, and improves the economic benefits of the entire hydrometallurgical process. The method of the present invention can effectively decompose the basic sulfate in the product, reduce the content of sulfate, and avoid the negative impact of sulfate on downstream processes, such as equipment corrosion. The method of the present invention has good applicability to different precipitation methods and different systems, and enhances the flexibility and adaptability of the process. Therefore, through the method of the present application, the content of nickel and cobalt in the product can be increased, the impurity content can be reduced; the subsequent processing cost can be reduced; the sulfate problem can be improved; the flexibility is high, the applicability is strong, and the economic benefits and environmental friendliness of the hydrometallurgical process are improved as a whole. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0022] Figure 1 A flow chart of a method for increasing the main component in a nickel-cobalt hydroxide intermediate product according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] As described in the background technology section, in the prior art, the nickel cobalt hydroxide intermediate product has a relatively high content of impurities such as magnesium and manganese, and a relatively high content of sulfate, which leads to an increase in subsequent refining production costs. To solve this technical problem, the present application provides a method for increasing the main components in the nickel cobalt hydroxide intermediate product.

[0025] In order to solve the above problems, the present invention provides a method for improving the main components in a nickel-cobalt hydroxide intermediate product. The nickel-cobalt hydroxide intermediate product includes hydroxides and basic sulfates of nickel ions, cobalt ions, manganese ions, and magnesium ions. The improvement method includes: step S100, using an alkaline substance to perform a first activation on the nickel-cobalt hydroxide intermediate product slurry to obtain a first activated product slurry; step S200, adjusting the solid content of the first activated product slurry; step S300, using a reducing agent to perform a second activation on the first activated product slurry to obtain a second activated product slurry; step S400, adjusting the solid content of the second activated product slurry; step S500, adding the second activated product slurry to a nickel-cobalt solution for conversion reaction to obtain nickel-cobalt hydroxide and a converted liquid.

[0026] The method of the present invention can significantly increase the total content of nickel and cobalt in nickel cobalt hydroxide to a level of more than 50%, while effectively reducing the content of impurities such as magnesium and manganese, and optimizing product quality. The reduction in impurity content reduces the complexity and cost of subsequent refining and separation processes, and improves the economic benefits of the entire hydrometallurgical process. The method of the present invention can effectively decompose the basic sulfate in the product, reduce the content of sulfate, and avoid the negative impact of sulfate on downstream processes, such as equipment corrosion. The method of the present invention has good applicability to different precipitation methods and different systems, and enhances the flexibility and adaptability of the process. Therefore, through the method of the present application, the content of nickel and cobalt in the product can be increased, the impurity content can be reduced; the subsequent processing cost can be reduced; the sulfate problem can be improved; the flexibility is high, the applicability is strong, and the economic benefits and environmental friendliness of the hydrometallurgical process are improved as a whole.

[0027] Specifically, the alkaline activation mechanism in the above step S100: can improve the reactivity of certain impurities (such as magnesium hydroxide) in the nickel cobalt hydroxide intermediate product, making it easier to undergo a replacement reaction with nickel cobalt ions during the subsequent conversion process. In step S200 / S400, the importance of solid content adjustment: the solid content of the slurry directly affects the efficiency and required energy of the subsequent reaction. The slurry of appropriate concentration can maximize the reaction contact area, accelerate the reaction rate, and reduce the processing energy consumption. Reductive activation mechanism in step S300: the addition of the reducing agent plays a role in reducing high-valent manganese, converting it into low-valent manganese hydroxide, thereby increasing the reactivity of manganese and facilitating the replacement reaction with nickel cobalt ions. The principle of the conversion reaction in step S500: the conversion reaction carried out in the nickel cobalt-containing solution is essentially to use the activated nickel cobalt hydroxide intermediate product to carry out a replacement reaction with the nickel cobalt ions in the nickel cobalt-containing solution, and finally generate a higher purity nickel cobalt hydroxide, and at the same time, the impurity ions are released into the solution, which is convenient for subsequent separation and treatment.

[0028] In addition, the synergistic effect of the first alkaline activation and the second reductive activation steps can specifically treat the main impurities in the nickel cobalt hydroxide intermediate product, such as magnesium hydroxide and high-valent manganese, by changing their chemical forms, making them easy to be replaced by nickel cobalt ions in the subsequent conversion reaction, thereby improving the purity of the product. The order of the first alkaline activation and the second reductive activation steps helps to further ensure that the manganese in the second activation product slurry is divalent manganese, thereby ensuring the efficiency and effect of the conversion reaction.

[0029] In a preferred embodiment, in order to increase the activity of magnesium hydroxide and manganese hydroxide in the conversion reaction and reduce the risk of oxidation after long-term storage, the second activation product filter cake is returned to the aforementioned conversion reaction within 10 minutes, more preferably within 3 minutes.

[0030] The regulation of solid content is crucial for improving the reaction efficiency of the activation and conversion reaction process. Too low solid content is easy to reduce the concentration of alkaline substances to the nickel cobalt hydroxide intermediate product slurry, affecting the reaction rate. Too high solid content may reduce the reaction efficiency due to the increase of system viscosity. Therefore, based on improving the purity and reaction efficiency of the final obtained nickel cobalt hydroxide product, in some preferred embodiments of the present application, in the above-mentioned step S100, the solid content of the nickel cobalt hydroxide intermediate product slurry is 0.1%~35%, preferably 5%~20%, so as to be more helpful to improve the efficiency of activation and conversion reaction, promote the substitution reaction of nickel cobalt ions and impurity ions, and reduce energy consumption and processing costs. Wherein, the solid content of the nickel cobalt hydroxide intermediate product slurry can be 0.1%, 0.3%, 0.5%, 1%, 1.2%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 5%, 10%, 15%, 20%, 25%, 30% or 35%, of course not limited to any one value in 0.1%~35%.

[0031] In some implementations of the present application, in the above step S100, the nickel cobalt hydroxide intermediate product slurry is obtained by pretreating the nickel cobalt hydroxide intermediate product, and the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide slurry or a nickel cobalt hydroxide filter cake.

[0032] The nickel cobalt hydroxide intermediate product can have a wide range of sources. For example, the nickel cobalt hydroxide intermediate product obtained by high-pressure leaching of laterite nickel ore by hydrometallurgy can be a nickel cobalt hydroxide slurry or a nickel cobalt hydroxide filter cake. This type of nickel cobalt hydroxide can be obtained after some pretreatment to obtain a nickel cobalt hydroxide intermediate product slurry suitable for step S100, thereby facilitating subsequent activation treatment thereof.

[0033] In some implementations of the present application, in the above step S100, when the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide slurry, the nickel cobalt hydroxide slurry is concentrated or diluted to obtain a nickel cobalt hydroxide intermediate product slurry; when the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide filter cake, the nickel cobalt hydroxide filter cake is slurried to obtain a nickel cobalt hydroxide intermediate product slurry.

[0034] By using nickel cobalt hydroxide slurry or nickel cobalt hydroxide filter cake as raw material and through slurrying, concentration or dilution treatment, the uniformity and reaction contact area of ​​the nickel cobalt hydroxide intermediate product slurry are improved, which is beneficial to the smooth progress of the subsequent activation and conversion reaction process.

[0035] In some implementations of the present application, in the above step S100, the alkaline substance is selected from any one or more of sodium hydroxide, potassium hydroxide, and ammonium hydroxide.

[0036] Activation using alkaline substances such as sodium hydroxide, potassium hydroxide or ammonium hydroxide helps to increase the reactivity of magnesium hydroxide in the nickel-cobalt hydroxide intermediate product, accelerate its replacement reaction with nickel-cobalt ions, and effectively reduce the magnesium content in the nickel-cobalt hydroxide product.

[0037] Carrying out the first activation under suitable temperature conditions helps to maximize the reaction efficiency of the first activation. In some embodiments of the present application, in step S100, the temperature of the first activation is 25°C~260°C, preferably 80°C~150°C, and the time of the first activation is 0.1h~10h, preferably 2h~8h, which not only helps to reduce energy consumption, but also reduces the occurrence of side reactions and improves the purity and quality of nickel cobalt hydroxide products. Among them, the temperature of the first activation can be 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 120°C, 150°C, 180°C, 200°C, 230°C or 260°C, and is certainly not limited to any one value in 25°C~260°C. The time of the first activation can be 0.1 h, 1 h, 1.5 h, 2 h, 3 h, 4 h, 5 h, 6 h, 8 h, 9 h or 10 h, and is certainly not limited to any value between 0.1 h and 10 h.

[0038] The amount of alkaline substance is crucial to the activation effect of the nickel cobalt hydroxide intermediate product. The reasonable amount of alkaline substance is helpful to activate impurities without causing an excessively high alkaline environment. In some embodiments of the present application, it is preferred that in the above step S100, the mass of the alkaline substance is 0.05% to 20% of the dry weight of the nickel cobalt hydroxide intermediate product slurry, preferably 0.5% to 5%, so as to be more helpful to improve the stability of the nickel cobalt hydroxide product and the efficiency of subsequent treatment. Among them, the mass of the alkaline substance can be 0.05%, 0.1%, 0.3%, 0.5%, 1%, 1.2%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 5%, 10%, 15% or 20% of the dry weight of the nickel cobalt hydroxide intermediate product slurry, and is certainly not limited to any one value in 0.05% to 20%.

[0039] In some embodiments of the present application, in the above step S300, the reducing agent is selected from any one or more of sodium sulfite, potassium sulfite, ammonium sulfite, sodium pyrosulfite, potassium pyrosulfite, ammonium pyrosulfite and sulfur dioxide.

[0040] The use of reducing agents such as sodium sulfite and potassium sulfite for the first activation effectively reduces the valence state of manganese in the nickel cobalt hydroxide intermediate product, increases its reaction activity, promotes the replacement reaction between manganese and nickel cobalt ions, and reduces the manganese content in the final nickel cobalt hydroxide product.

[0041] Carrying out the second activation under suitable temperature and time conditions can maximize the efficiency of the second activation. In some preferred embodiments of the present application, in the above step S300, the temperature of the second activation is 25°C~260°C, preferably 80°C~150°C, and the time of the second activation is 0.1 h~10h, preferably 2h~8h, so as to help reduce energy waste step by step, reduce the occurrence of side reactions, and improve the purity and quality of the final obtained nickel cobalt hydroxide product. Among them, the temperature of the second activation can be 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 120°C, 150°C, 180°C, 200°C, 230°C or 260°C, of ​​course, not limited to any one value in 25°C~260°C. The time for the second activation can be 0.1 h, 1 h, 1.5 h, 2 h, 3 h, 4 h, 5 h, 6 h, 8 h, 9 h or 10 h, and is certainly not limited to any value between 0.1 h and 10 h.

[0042] In some embodiments of the present application, in the above step S300, the amount of the substance derived from the sulfite group in the reducing agent is 0.1 to 5 times the amount of the substance of the manganese ion in the nickel cobalt hydroxide intermediate product slurry.

[0043] The amount of the substance of the sulfite group in the reducing agent is 0.1 to 5 times, preferably 0.2 to 1.5 times, of the amount of the substance of the manganese ion in the nickel cobalt hydroxide intermediate product. This ratio is conducive to improving the effective reduction effect of high-valent manganese, while reducing the risk of excessive addition of the reducing agent and reducing the complexity of subsequent treatment. Among them, the amount of the substance of the sulfite group in the reducing agent can be 0.1 times, 0.2 times, 0.3 times, 0.4 times, 0.5 times, 0.6 times, 0.7 times, 0.8 times, 0.9 times, 1 times, 1.1 times, 1.2 times, 1.3 times, 1.4 times, 1.5 times, 2 times, 2.3 times, 2.5 times, 2.8 times, 3 times, 3.5 times, 4 times, 4.5 times or 5 times of the amount of the substance of the manganese ion in the nickel cobalt hydroxide intermediate product, and is certainly not limited to any value in the range of 0.1 to 5 times.

[0044] In some embodiments of the present application, in the above step S200, the solid content of the first activated product slurry is 0.1% to 35%, preferably 5% to 20%; the process of adjusting the solid content of the first activated product slurry includes: concentrating or diluting the first activated product slurry; or sequentially performing solid-liquid separation and slurry treatment on the first activated product slurry. Among them, the solid content of the first activated product slurry can be 0.1%, 0.3%, 0.5%, 1%, 1.2%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 5%, 10%, 15%, 20%, 25%, 30% or 35%, and is certainly not limited to any one value between 0.1% and 35%.

[0045] Adjusting the solid content of the first activated product slurry helps to optimize the conditions for the second activation, thereby improving the efficiency of the second activation, while reducing energy consumption and improving the economy of the entire process.

[0046] The optimization of parameters such as temperature, time and liquid-solid ratio of the conversion reaction helps to promote the replacement reaction of nickel-cobalt ions and impurities to the greatest extent, improve the metal recovery rate, and reduce energy consumption and processing costs. Therefore, in some embodiments of the present application, it is preferred that in step S500, the temperature of the conversion reaction is 25°C~260°C, preferably 80~150°C, the time of the conversion reaction is 0.1h~10h, preferably 2h~8h; the liquid-solid ratio of the conversion reaction is 1~10:1, preferably 3~10:1. Among them, the temperature of the conversion reaction can be 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 120°C, 150°C, 180°C, 200°C, 230°C or 260°C, of ​​course, not limited to any one value of 25°C~260°C. The time of the conversion reaction can be 0.1h, 1h, 1.5h, 2h, 3h, 4h, 5h, 6h, 8h, 9h or 10h, and is certainly not limited to any value between 0.1h and 10h. The liquid-to-solid ratio of the conversion reaction can be 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 or 10:1, and is certainly not limited to any value between 1 and 10:1.

[0047] In some embodiments of the present application, in the above step S500, the nickel cobalt hydroxide intermediate product is obtained from the nickel-containing solution by a precipitation method, and the precipitation method is selected from any one of magnesium oxide precipitation method, magnesium hydroxide precipitation method, sodium hydroxide lithium precipitation method, potassium hydroxide lithium precipitation method, calcium oxide precipitation method and calcium hydroxide precipitation method.

[0048] Different precipitation methods have an impact on the original composition of the nickel cobalt hydroxide intermediate product. The optimized precipitation method above is conducive to providing a nickel cobalt hydroxide intermediate product raw material that is more suitable for subsequent processing and improving the efficiency of the main component enhancement method in the entire nickel cobalt hydroxide intermediate product.

[0049] Different leaching systems (sulfuric acid, hydrochloric acid, nitric acid) will affect the solubility and chemical form of impurities in nickel cobalt hydroxide. Selecting a suitable leaching system helps to further optimize the separation of impurities and improve the recovery efficiency of nickel and cobalt. In some embodiments of the present application, it is preferred that in the above step S500, the nickel-containing solution includes a laterite nickel ore leaching system, and the laterite nickel ore leaching system is selected from any one or more of laterite nickel ore sulfuric acid leaching liquid, laterite nickel ore hydrochloric acid leaching liquid and laterite nickel ore nitric acid leaching liquid, so as to further promote the separation of impurities and improve the recovery rate of nickel and cobalt.

[0050] In addition, the method for improving the main component in the nickel cobalt hydroxide intermediate product of the present invention is preferably used for the nickel cobalt hydroxide intermediate product obtained by precipitation of the liquid after sulfuric acid leaching of laterite nickel ore. The nickel content of the nickel cobalt hydroxide intermediate product is 35-41%, the cobalt content is 3-4%, the magnesium content is 1-5%, the manganese content is 5-8%, and the sulfate content is 4-5%. Through the method for improving the main component in the nickel cobalt hydroxide intermediate product, the nickel content of the final nickel cobalt hydroxide product is 45-50%, the cobalt content is 3-5%, the magnesium content is 0.05-1%, the manganese content is 0.5-2%, and the sulfate content is 0.5-1.5%.

[0051] The preferred nickel-cobalt solution is a solution obtained by liquid precipitation after iron and aluminum removal in the laterite nickel ore hydrometallurgical process to recover nickel-cobalt hydroxide intermediate products and nickel-cobalt sulfate solution, wherein Ni 2+ The content is 2~6g / L, Co 2+ The content is 0.1~0.5g / L, Mg 2+ The content is 2~10g / L, Mn 2+ The content is 1~5g / L.

[0052] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0053] The objects of the following embodiments are the recovery of nickel cobalt hydroxide intermediate products and nickel cobalt sulfate solution by liquid precipitation after iron and aluminum removal in the hydrometallurgical process of laterite nickel ore, wherein the ion components in the nickel cobalt sulfate solution are as follows:

[0054]

[0055] Example 1

[0056] Method for improving the main components of nickel-cobalt hydroxide intermediate products by liquid precipitation after iron and aluminum removal in laterite nickel ore hydrometallurgy process:

[0057] Reference Figure 1 The flowchart of the method for improving the main component in the nickel cobalt hydroxide intermediate product is shown. The nickel cobalt hydroxide intermediate product filter cake obtained by precipitation in the sulfate system has a nickel content of 39%, a cobalt content of 3%, a magnesium content of 2%, a manganese content of 7%, and a sulfate content of 4%. It is slurried with water to a solid content of 20% to obtain a nickel cobalt hydroxide intermediate product slurry. Sodium hydroxide is added to the nickel cobalt hydroxide intermediate product slurry for the first activation. The mass of sodium hydroxide is 2% of the dry weight of the nickel cobalt hydroxide intermediate product slurry. The temperature of the first activation is 150°C and the time is 2 hours to obtain a first activated product slurry. The first activated product slurry is then filtered and slurried again to a solid content of 20%.

[0058] Sodium sulfite is added to the first activated product slurry with a solid content of 20% for a second activation. The amount of the substance of the sulfite group is 0.2 times the amount of the substance of the manganese ion in the nickel cobalt hydroxide intermediate product slurry. The temperature of the second activation is 150°C and the time is 2 hours to obtain a second activated product slurry. The second activated product slurry is then filtered, and the obtained second activated product filter cake is added to a nickel cobalt sulfate solution within 3 minutes. A conversion reaction is carried out under a liquid-solid ratio of 3:1. The temperature of the conversion reaction is 150°C and the time is 2 hours. After filtering and washing, a high-quality nickel cobalt hydroxide product is obtained, wherein the nickel content is 48%, the cobalt content is 4%, the magnesium content is 0.1%, the manganese content is 0.8%, and the sulfate content is 0.6%.

[0059] Example 2

[0060] The only difference between this embodiment and embodiment 1 is that the solid content of the nickel cobalt hydroxide intermediate product slurry is 5%, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 48.5%, the cobalt content is 4.5%, the magnesium content is 0.08%, the manganese content is 0.6%, and the sulfate content is 0.5%.

[0061] Example 3

[0062] The only difference between this embodiment and embodiment 1 is that the solid content of the nickel cobalt hydroxide intermediate product slurry is 35%, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 48.7%, the cobalt content is 3.5%, the magnesium content is 0.3%, the manganese content is 1.2%, and the sulfate content is 0.8%.

[0063] Example 4

[0064] The only difference between this embodiment and embodiment 1 is that the solid content of the nickel cobalt hydroxide intermediate product slurry is 0.1%, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 48%, the cobalt content is 4%, the magnesium content is 0.1%, the manganese content is 0.8%, and the sulfate content is 0.6%.

[0065] Example 5

[0066] This embodiment is different from Embodiment 1 only in that ammonium hydroxide is added to the nickel-cobalt hydroxide intermediate product slurry for the first activation, and nickel-cobalt hydroxide is finally obtained. After testing, the nickel content is 47.7%, the cobalt content is 3.8%, the magnesium content is 0.1%, the manganese content is 0.8%, and the sulfate content is 1.3%.

[0067] Example 6

[0068] This embodiment is different from embodiment 1 only in that the temperature of the first activation is 80° C., the time of the first activation is 8 hours, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 48.9%, the cobalt content is 3.7%, the magnesium content is 0.1%, the manganese content is 0.8%, and the sulfate content is 0.8%.

[0069] Example 7

[0070] This embodiment is different from embodiment 1 only in that the temperature of the first activation is 60° C., the time of the first activation is 10 h, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 47.7%, the cobalt content is 3.7%, the magnesium content is 0.1%, the manganese content is 0.8%, and the sulfate content is 1.2%.

[0071] Example 8

[0072] This embodiment differs from Embodiment 1 only in that the mass of sodium hydroxide is 5% of the dry weight of the nickel-cobalt hydroxide intermediate product slurry, and nickel-cobalt hydroxide is finally obtained. After testing, the nickel content is 48.2%, the cobalt content is 4.3%, the magnesium content is 0.1%, the manganese content is 0.8%, and the sulfate content is 0.5%.

[0073] Example 9

[0074] This embodiment differs from Embodiment 1 only in that the mass of sodium hydroxide is 0.4% of the dry weight of the nickel-cobalt hydroxide intermediate product slurry, and nickel-cobalt hydroxide is finally obtained. After testing, the nickel content is 47.8%, the cobalt content is 3.8%, the magnesium content is 0.1%, the manganese content is 0.8%, and the sulfate content is 1.3%.

[0075] Example 10

[0076] This embodiment is different from embodiment 1 only in that the reducing agent is ammonium sulfite, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 48.3%, the cobalt content is 4.1%, the magnesium content is 0.1%, the manganese content is 1.2%, and the sulfate content is 0.6%.

[0077] Embodiment 11

[0078] This embodiment is different from embodiment 1 only in that the temperature of the second activation is 80° C., the time of the second activation is 8 hours, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 47.5%, the cobalt content is 3.9%, the magnesium content is 0.1%, the manganese content is 1.2%, and the sulfate content is 0.6%.

[0079] Example 12

[0080] This embodiment is different from embodiment 1 only in that the temperature of the second activation is 60° C., the time of the second activation is 10 h, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 48.1%, the cobalt content is 3.7%, the magnesium content is 0.1%, the manganese content is 1.5%, and the sulfate content is 0.6%.

[0081] Embodiment 13

[0082] This embodiment differs from Embodiment 1 only in that the amount of the substance of the sulfite group is 1.5 times the amount of the substance of the manganese ion in the nickel cobalt hydroxide intermediate product slurry, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 48.5%, the cobalt content is 4.6%, the magnesium content is 0.1%, the manganese content is 0.5%, and the sulfate content is 0.6%.

[0083] Embodiment 14

[0084] This embodiment differs from Embodiment 1 only in that the amount of the substance of the sulfite group is 0.1 times the amount of the substance of the manganese ion in the nickel cobalt hydroxide intermediate product slurry, and nickel cobalt hydroxide is finally obtained. After testing, the nickel content is 47.6%, the cobalt content is 3.8%, the magnesium content is 0.1%, the manganese content is 1.5%, and the sulfate content is 0.6%.

[0085] Embodiment 15

[0086] The only difference between this embodiment and embodiment 1 is that the obtained second activated product filter cake is added to the nickel cobalt sulfate solution within 10 minutes to finally obtain nickel cobalt hydroxide. After testing, the nickel content is 47.6%, the cobalt content is 3.8%, the magnesium content is 0.1%, the manganese content is 1.2%, and the sulfate content is 0.6%.

[0087] Comparative Example 1

[0088] The nickel cobalt hydroxide intermediate product filter cake obtained by precipitation in the sulfate system contains 39% nickel, 3% cobalt, 2% magnesium, 7% manganese, and 4% sulfate, which is slurried with water to 20% to obtain a nickel cobalt hydroxide intermediate product slurry. Sodium sulfite is added to the nickel cobalt hydroxide intermediate product slurry for the first activation, the temperature of the first activation is 150°C, the time is 2h, and the first activated product slurry is obtained, and then the first activated product slurry is filtered and slurried again to a solid content of 20%.

[0089] Sodium hydroxide was added to the first activated product slurry with a solid content of 20% for a second activation. The temperature of the second activation was 150°C for 2 hours to obtain a second activated product slurry. The second activated product slurry was then filtered, and the filter cake was added to a nickel cobalt sulfate solution containing 3 g / L nickel and 0.3 g / L cobalt. A conversion reaction was carried out under a liquid-solid ratio of 3:1. The temperature of the conversion reaction was 150°C for 2 hours. After filtering and washing, a high-quality nickel cobalt hydroxide product was obtained, wherein the nickel content was 45%, the cobalt content was 3%, the magnesium content was 0.1%, the manganese content was 4%, and the sulfate content was 0.6%.

[0090] Among them, it should be noted that the solid content of the nickel cobalt hydroxide intermediate product slurry in Example 4 is 0.1%, which has little effect on the quality of the final nickel cobalt hydroxide product. It mainly leads to an increase in water consumption, and the corresponding wastewater post-treatment is relatively cumbersome, and the treatment time is relatively prolonged, which is not conducive to cost reduction.

[0091] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0092] The method of the present invention can significantly increase the total content of nickel and cobalt in nickel cobalt hydroxide to a level of more than 50%, while effectively reducing the content of impurities such as magnesium and manganese, and optimizing product quality. The reduction in impurity content reduces the complexity and cost of subsequent refining and separation processes, and improves the economic benefits of the entire hydrometallurgical process. The method of the present invention can effectively decompose the basic sulfate in the product, reduce the content of sulfate, and avoid the negative impact of sulfate on downstream processes, such as equipment corrosion. The method of the present invention has good applicability to different precipitation methods and different systems, and enhances the flexibility and adaptability of the process. Therefore, through the method of the present application, the content of nickel and cobalt in the product can be increased, the impurity content can be reduced; the subsequent processing cost can be reduced; the sulfate problem can be improved; the flexibility is high, the applicability is strong, and the economic benefits and environmental friendliness of the hydrometallurgical process are improved as a whole.

[0093] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for increasing the main components in a nickel-cobalt hydroxide intermediate product, wherein the nickel-cobalt hydroxide intermediate product comprises hydroxides and basic sulfates of nickel ions, cobalt ions, manganese ions, and magnesium ions, characterized in that: The lifting method comprises: Step S100, using an alkaline substance to perform a first activation on the nickel cobalt hydroxide intermediate product slurry to obtain a first activated product slurry; Step S200, adjusting the solid content of the first activated product slurry; Step S300, performing a second activation on the first activated product slurry using a reducing agent to obtain a second activated product slurry; Step S400, performing solid-liquid separation on the second activated product slurry to obtain a second activated filter cake; Step S500, adding the second activated filter cake into a nickel-cobalt-containing solution to carry out a conversion reaction to obtain nickel-cobalt hydroxide and a converted liquid; The nickel-cobalt solution is obtained by liquid precipitation after iron and aluminum removal in the laterite nickel ore hydrometallurgical process to recover nickel-cobalt hydroxide intermediate products and nickel-cobalt sulfate solution, wherein Ni 2+ The content is 2~6g / L, Co 2+ The content is 0.1~0.5g / L, Mg 2+ The content is 2~10g / L, Mn 2+ The content is 1~5g / L.

2. The method for improving the main component in the nickel cobalt hydroxide intermediate product according to claim 1, characterized in that: In the step S100, the solid content of the nickel cobalt hydroxide intermediate product slurry is 0.1% to 35%.

3. The method for improving the main component in the nickel cobalt hydroxide intermediate product according to claim 2, characterized in that: In the step S100, the nickel cobalt hydroxide intermediate product slurry is obtained by pretreating the nickel cobalt hydroxide intermediate product, and the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide slurry or a nickel cobalt hydroxide filter cake.

4. The method for increasing the main component in the nickel cobalt hydroxide intermediate product according to claim 3, characterized in that: In the step S100, when the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide slurry, the nickel cobalt hydroxide slurry is concentrated or diluted to obtain the nickel cobalt hydroxide intermediate product slurry; when the nickel cobalt hydroxide intermediate product is a nickel cobalt hydroxide filter cake, the nickel cobalt hydroxide filter cake is slurried to obtain the nickel cobalt hydroxide intermediate product slurry.

5. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In the step S100, the alkaline substance is selected from any one or more of sodium hydroxide, potassium hydroxide, and ammonium hydroxide.

6. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In the step S100, the temperature of the first activation is 25° C. to 260° C., and the time of the first activation is 0.1 h to 10 h.

7. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In the step S100, the mass of the alkaline substance is 0.05% to 20% of the dry weight of the nickel cobalt hydroxide intermediate product slurry.

8. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In step S300, the reducing agent is selected from any one or more of sodium sulfite, potassium sulfite, ammonium sulfite, sodium pyrosulfite, potassium pyrosulfite, ammonium pyrosulfite and sulfur dioxide.

9. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In the step S300, the temperature of the second activation is 25°C to 260°C, and the time of the second activation is 0.1h to 10h.

10. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In the step S300, the amount of the substance derived from the sulfite group in the reducing agent is 0.1 to 5 times the amount of the substance of the manganese ion in the nickel cobalt hydroxide intermediate product slurry.

11. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In the step S200, the solid content of the first activated product slurry is 0.1% to 35%; the process of adjusting the solid content of the first activated product slurry includes: Concentrating or diluting the first activated product slurry; Alternatively, the first activated product slurry is subjected to solid-liquid separation and slurry treatment in sequence.

12. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In the step S500, the temperature of the conversion reaction is 25°C to 260°C, the time of the conversion reaction is 0.1h to 10h; and the liquid-to-solid ratio of the conversion reaction is 1 to 10:

1.

13. The method for increasing the main component in the nickel-cobalt hydroxide intermediate product according to any one of claims 1 to 4, characterized in that: In step S500, the nickel cobalt hydroxide intermediate product is obtained from a nickel-containing solution by a precipitation method, and the precipitation method is selected from any one of a magnesium oxide precipitation method, a magnesium hydroxide precipitation method, a sodium hydroxide lithium precipitation method, a potassium hydroxide lithium precipitation method, a calcium oxide precipitation method and a calcium hydroxide precipitation method.

14. The method for increasing the main component in the nickel cobalt hydroxide intermediate product according to claim 13, characterized in that: In the step S500, the nickel-containing solution includes a laterite nickel ore leaching system, and the laterite nickel ore leaching system is selected from any one or more of a laterite nickel ore sulfuric acid leaching solution, a laterite nickel ore hydrochloric acid leaching solution, and a laterite nickel ore nitric acid leaching solution.

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