Method for preparing ternary precursor by combined treatment of nickel-iron water and battery black powder

Abstract

The application discloses a method for preparing ternary precursors by jointly treating nickel-iron water and battery black powder, which comprises the following steps: dissolving the battery black powder in dilute acid to obtain a black powder solution; after sulfuration, the nickel-iron water is slowly added into the black powder solution, and acid liquor is added for leaching; during the leaching process, the pH of the leaching end point is controlled by using the battery black powder and / or battery black powder leaching residue; after the leaching is completed, hydrolysis and impurity removal are carried out; after the nickel-cobalt-manganese ratio is adjusted, ternary nickel-cobalt-manganese precursors are obtained through hydrolysis and co-precipitation. The method combines pyrometallurgy and hydrometallurgy, extracts high-value nickel in the nickel-iron water in pyrometallurgy by hydrometallurgy, and improves the nickel grade of the system; and pyrometallurgy provides the required heat energy for hydrometallurgy, thereby reducing energy consumption.

Description

TECHNICAL FIELD

[0001] The application relates to a method for combined treatment of nickel-iron melt and battery black powder, in particular to a method for preparing a ternary precursor by combined treatment of nickel-iron melt and battery black powder, and belongs to the field of ternary precursor synthesis. BACKGROUND

[0002] There are two kinds of processes for treating laterite ore, namely, pyrometallurgical process and hydrometallurgical process. As for the pyrometallurgical process, the mainstream process in the world is rotary kiln roasting-electric furnace smelting (RKEF method), and some smelting plants use rotary kiln direct reduction method, and some pilot plants use direct current arc furnace smelting.

[0003] The product of pyrometallurgical process of laterite nickel ore is nickel-iron, and the nickel-iron is sulfidized to form nickel matte. The main processes for smelting nickel-iron in China are blast furnace smelting and arc furnace smelting. The nickel-iron alloy obtained by blast furnace smelting generally has a low grade, and the blast furnace smelting can produce nickel-iron alloy containing about 8% of nickel; the alloy obtained by arc furnace smelting has a high grade, and generally contains more than 10% of nickel. At present, most of the domestic plants use the nickel-iron melt with a grade of 8-10% to produce stainless steel, however, the production of stainless steel from the nickel-iron melt has high energy consumption, and the nickel-iron melt has many impurities, large quality fluctuation and low product profit, so the high-value nickel in the nickel-iron melt is not effectively utilized.

[0004] The ternary precursor material of nickel-cobalt-manganese is a popular material in the battery industry, and the market price is always high. The battery recycling industry uses battery black powder to leach nickel-cobalt-manganese, and the hydrometallurgy is used to prepare the ternary precursor material of nickel-cobalt-manganese. For example, Chinese patent CN112646976 B uses waste lithium ion battery black powder and nickel-cobalt sulfide ore to cooperatively leach nickel-cobalt-manganese black powder, a large amount of reducing agent and leaching aid is consumed in the leaching process, a large amount of fuel is consumed in the heating process, the heating time is long, and the efficiency is low. Some battery black powder has a low nickel grade, and an additional nickel source needs to be added after the leaching to produce high-nickel precursor, and the additional nickel-cobalt sulfide ore not only increases the production cost, but also increases the impurities in the leaching solution, so that the difficulty of separating impurities in the subsequent precursor synthesis process is high. SUMMARY

[0005] In view of the problems in the prior art that the nickel in the nickel-iron melt cannot be effectively utilized, and the high energy consumption and difficulty in directly obtaining high-purity high-nickel precursor in the process of preparing nickel-cobalt-manganese ternary precursor by leaching nickel-cobalt-manganese from battery black powder, the purpose of the present application is to provide a method for preparing ternary precursor by combined treatment of nickel-iron melt and battery black powder. The method combines pyrometallurgy and hydrometallurgy, extracts high-value nickel from the nickel-iron melt in pyrometallurgy, and improves the nickel grade of the system; and pyrometallurgy provides the heat energy required for hydrometallurgy, reducing energy consumption. At the same time, the in-situ generated nickel matte is high-ice nickel, and the high nickel content in the high-ice nickel can be used to prepare high-nickel ternary precursor, and the purity of nickel is high, the valence of nickel is +2, and there is no other impurity influence, and the particle size of the produced precursor is small and uniform, and the specific surface area is larger.

[0006] In order to achieve the above technical purpose, the present application provides a method for preparing ternary precursor by combined treatment of nickel-iron melt and battery black powder, which is to dissolve battery black powder in dilute acid to obtain black powder solution; after sulfidation, the nickel-iron melt is slowly added to the black powder solution, and acid solution is added for leaching, and the pH of the leaching end point is controlled by battery black powder and / or black powder leaching residue during the leaching process; after the leaching is completed, hydrolysis and impurity removal are carried out, and then the nickel-cobalt-manganese ratio is adjusted, and the nickel-cobalt-manganese ternary precursor is obtained by hydrolysis co-precipitation.

[0007] The technical scheme of the present application ingeniously combines the advantages of pyrometallurgy and hydrometallurgy, directly extracts the nickel in the nickel-iron melt in pyrometallurgy by hydrometallurgy, and the nickel-iron melt supplements additional nickel source, which provides guarantee for producing high-nickel ternary precursor from low-grade battery black powder, and more effectively utilizes the high-value nickel in the nickel-iron melt, and relatively the prior art eliminates the complex operation of separating nickel from nickel-iron alloy, and the high-temperature nickel-iron melt produced by pyrometallurgy can provide heat for the leaching process, reducing heating cost and heating time is faster and more efficient. The key of the present application is to first use sulfur source to sulfidize the nickel-iron melt in-situ to generate nickel matte, which is high-ice nickel with a nickel content of about 26% and high purity, which not only makes the particle size of the prepared ternary precursor more uniform and increases the specific surface area of the ternary precursor, but also does not introduce impurities into the ternary precursor due to its high purity. By first dissolving the battery black powder in a weak acid solution and then adding the high-temperature nickel-iron melt after sulfidation, a buffering effect can be achieved to prevent the solution from boiling, thereby facilitating the leaching of nickel, cobalt and manganese in the battery black powder into sulfates in the hot acid solution and the dissolution of nickel in the nickel-iron melt into sulfates. The sulfur source in the present application first acts as an oxidizing agent to sulfidize the nickel-iron, and generates hydrogen sulfide upon contact with acid, and then acts as a reducing agent to reduce the black powder, providing both oxidizing and reducing agents, without the need to add conventional reducing agents such as hydrogen peroxide or sulfur dioxide to reduce nickel, cobalt and manganese in the battery black powder to divalent, which not only saves auxiliary material cost, but also speeds up the reaction and directly obtains high-purity high-nickel ternary precursor.

[0008] As a preferred scheme, the battery black powder is waste old nickel-cobalt-manganese ternary battery positive material black powder, the nickel content of which is 5-30%, the cobalt content is 1-10%, and the manganese content is 1-10%. Further preferably, the nickel content of the black powder is 18-25%. If the nickel content in the battery black powder is too low, it means that the quality of the black powder is too low to meet the leaching requirements; if the nickel content in the battery black powder is too high, the contents of cobalt and manganese are relatively low, and additional cobalt and manganese sources are needed to increase the cost.

[0009] As a preferred scheme, the battery black powder leaching residue is a defective product in the leaching process, which has a lower grade of nickel, cobalt and manganese than the battery black powder.

[0010] As a preferred scheme, the nickel-iron melt is a high-temperature nickel-iron melt produced by pyrometallurgy, with a temperature of 1300-1500 DEG C and a nickel content of 5-15%; further preferably, the nickel content of the nickel-iron melt is 9-12%. The nickel content of this grade can exactly meet the supplementing demand of the nickel source in the black powder; if the nickel content is too low, the nickel source content is insufficient; if the nickel content is too high, the nickel source is excessive, and additional cobalt and manganese sources are needed to supplement the nickel-cobalt-manganese ratio. Moreover, the high-temperature nickel-iron melt with a temperature of 1300-1500 DEG C can make the reaction unnecessary to be heated, which effectively utilizes the heat energy and reduces the energy consumption, and can make the reaction rate be twice the normal rate.

[0011] As a preferred scheme, the pH of the black powder solution is 2-4, and the solid-liquid ratio is 1 kg: 5-10 L; further preferably, the pH of the black powder solution is 2.5-3.5. The dilute acid is added to preliminarily dissolve the battery black powder, which plays a buffering role and prevents the battery black powder from being directly added into the high-temperature nickel-iron melt to cause explosive boiling, thereby causing the loss of nickel, cobalt and manganese and safety hazards.

[0012] As a preferred scheme, the dilute acid used in the present application is dilute sulfuric acid.

[0013] As a preferred scheme, the mass ratio of the battery black powder to the nickel-iron melt in the black powder solution is (1-10): 1; further preferably, the mass ratio of the battery black powder to the nickel-iron melt in the black powder solution is (5-8): 1. The temperature of the nickel-iron melt is as high as 1500 DEG C, and if the specific gravity of the nickel-iron melt is too high, the solution system will continue to boil over in the whole reaction, and there is too much residual nickel; if the specific gravity of the nickel-iron melt is too low, it cannot supplement enough nickel, which affects the production of the subsequent high-nickel precursor.

[0014] As a preferred scheme, the pH at the end of the leaching is 2-4; further preferably, the pH is 2.8-3.2. The pH at the end of the leaching in the present application needs to be strictly controlled, because the battery black powder contains a high content of iron and aluminum impurity ions, which are easy to form iron hydroxide or aluminum hydroxide colloid, thereby affecting the solid-liquid separation. The experiment shows that the solid-liquid separation effect is best in the range of pH 2.8-3.2.

[0015] As a preferred scheme, the sulfuration process uses solid sulfur and / or liquid sulfur as the sulfur source. Since solid sulfur directly reacts with the nickel-iron water, a large amount of smoke is generated, causing waste of sulfur and environmental pollution; liquid sulfur can be injected into the nickel-iron water for reaction, without generating smoke problems, therefore, further preferably, liquid sulfur, i.e., sulfur is first melted into liquid state at 120°C, and then added into the nickel-iron water.

[0016] As a preferred scheme, the mass ratio of the sulfur source to the nickel-iron water in the sulfuration process is 1:(5-20). If the sulfur source is too low, the sulfuration standard of high-ice nickel cannot be reached, which affects the leaching efficiency and there is not enough sulfide as a reducing agent; if the sulfur source is too high, the excess sulfur source also sulfurizes the iron in the nickel-iron water, thereby affecting the separation of impurities, and also causing waste of sulfur. Further preferably, the mass ratio is 1:(8-10).

[0017] As a preferred scheme, the leaching conditions are: temperature is 50-90°C, and initial pH is 0.5-1.5. Further preferably, the temperature is 70-80°C, and the initial pH is 0.5-0.8. In this range, the nickel, cobalt and manganese ions in the battery black powder and the nickel-iron water can be leached to the maximum extent.

[0018] As a preferred scheme, the hydrolysis co-precipitation conditions are: temperature is 60-80°C, and pH is 10-11. The synthesis temperature and the synthesis pH should be strictly in accordance with the above requirements, if out of the range, the morphology of the precursor may be irregularly changed, and the particle size of the precursor is not uniform. Further preferably, the temperature is 70-75°C, and the pH is 10.5-10.8.

[0019] As a preferred scheme, the hydrolysis impurity removal conditions are: pH is 4-6.

[0020] As a preferred scheme, the alkali liquor is at least one of sodium carbonate solution, sodium bicarbonate solution and sodium hydroxide solution. Further preferably, the alkali liquor is sodium carbonate solution, which reacts more gently, and the impurity removal process is not easy to cause the nickel and cobalt to precipitate together with the impurities due to excessive alkalinity.

[0021] As a preferred scheme, the mass fraction of the alkali liquor is 15-40%. Further preferably, the mass fraction of the alkali liquor is 25-30%. If the mass fraction of the alkali liquor is too low, the volume of the alkali liquor consumed is too much, and if the mass fraction of the alkali liquor is too high, local excessive alkalinity is easily formed, which causes the nickel and cobalt to precipitate together with the impurities.

[0022] As a preferred scheme, before the adjustment of the nickel-cobalt-manganese ratio, the solution needs to be concentrated by a thickener to 1.8-2.2 mol / L. Further preferably, the concentration of the thickener concentration is 2.0±0.05 mol / L.

[0023] As a preferred solution, the molar ratio of the adjusted nickel-cobalt-manganese is 5:2:3 or 6:2:2 or 8:1:1 or other common ratios.

[0024] Compared with the prior art, the beneficial technical features of the present application are:

[0025] 1) If the nickel in the nickel-iron melt is made into a stainless steel nickel-iron alloy in the traditional way, the value of the stainless steel material is low, and the present application extracts the high-value nickel in the nickel-iron melt by hydrometallurgy, and after preparation of the ternary precursor, the price is 2-4 times that of the stainless steel nickel-iron alloy.

[0026] 2) In the battery black powder leaching process, since the nickel, cobalt and manganese therein are all in high valence states, additional reducing agents need to be added for reduction. In the present application, the sulfur source first acts as an oxidizing agent to sulfidize the nickel-iron, and generates hydrogen sulfide upon encountering acid, and then acts as a reducing agent to reduce the black powder, thus providing both an oxidizing agent and a reducing agent, saving 50% of the auxiliary material cost.

[0027] 3) The solution needs to be heated to a certain temperature for the leaching process to proceed, and in the present application, the high-temperature nickel-iron melt enters the solution, and the high temperature generated allows the reaction to proceed without heating, thus eliminating the heating cost and reducing the heating time, and the reaction rate is twice that of the normal rate.

[0028] 4) The nickel grade in the battery black powder is low, and additional nickel sulfate needs to be added as a nickel source supplement for the preparation of the ternary precursor, while the nickel-iron melt provides an additional nickel source for the low-nickel-grade black powder, meeting the requirements for the preparation of high-nickel ternary precursors.

[0029] 5) The in-situ generated nickel matte in the present application is high-ice nickel, and the high nickel content in the high-ice nickel can be used to prepare high-nickel ternary precursors, realizing the full utilization of the nickel-iron melt, and at the same time, the purity of the nickel is high, the valence of the nickel is all +2, and there is no influence of other impurities, and the produced precursor has small and uniform particle size and larger specific surface area. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The process flow chart of the present application.

[0031] Figure 2 The SEM scanning electron micrograph of the 811 high-nickel precursor prepared in the present application. Figure 2 It can be seen that the precursor is spherical, has small and uniform particle size, and has a specific surface area as high as 11.74 m 2 / g. DETAILED DESCRIPTION

[0032] In order to facilitate the understanding of the present application, the following will describe the present application more fully and in detail with reference to the preferred embodiments, but the scope of protection of the present application is not limited to the following specific embodiments.

[0033] Unless otherwise defined, all terms used in the description employed herein have the same meaning as commonly understood by one of ordinary skill in the art. As used herein, the following professional terms are intended to have the following meanings.

[0034] Unless otherwise specified, all reagents, raw materials used in the present application are commercially available or can be prepared by known methods.

[0035] The content of nickel, iron and manganese in the black powder element and the content of nickel in the nickel-iron melt in the examples and comparative examples of the present application are shown as follows:

[0036] Element Nickel Cobalt Manganese Content / % 19.5 2.7 2.8

[0037] The content of nickel in the nickel-iron melt is 8.9%.

[0038] Example 1

[0039] The method for preparing ternary precursor by combined treatment of nickel-iron melt and battery black powder in the present example comprises the following steps:

[0040] (1) Put 3.2 tons of clean water into the reactor, and then put in 400 kg of black powder. After stirring evenly, slowly add concentrated sulfuric acid, and adjust the pH to 3.

[0041] (2) Put out 100 kg of nickel-iron melt in the smelting furnace, and maintain the original temperature (1500℃) in the ladle, and mix and stir with 10 kg of liquid sulfur.

[0042] (3) Slowly pour the sulfurized nickel-iron melt into the black powder solution, and continuously stir to prevent boiling during the pouring process.

[0043] (4) Add concentrated sulfuric acid to pH=0.5, and maintain the temperature at 80℃ for 1h.

[0044] (5) Continue to add black powder to the solution until the pH is adjusted to 3, and then filter.

[0045] (6) Add sodium carbonate to the solution until the pH is adjusted to 5, and then filter.

[0046] (7) The nickel-cobalt-manganese concentration is adjusted to a molar ratio of 8:1:1, and the 811 precursor is synthesized by co-precipitation reaction. After washing and drying, the yield of the precursor is 146 kg. The leaching rate of nickel, cobalt and manganese is all more than 99%, the prepared ternary precursor is spherical particle, the particle size D50 is 10.53 μm, and the specific surface area is 11.74 m 2 / g.

[0047] Example 2

[0048] A method for preparing a ternary precursor by combined treatment of nickel-iron water and battery black powder according to the embodiment comprises the following steps:

[0049] (1) 1.6 tons of clean water is poured into the reaction kettle, 200 kg of black powder is added, and after stirring evenly, concentrated sulfuric acid is slowly added, and the pH is adjusted to 3.

[0050] (2) 50 kg of nickel-iron water is discharged from the smelting furnace, and the original temperature (1500°C) is maintained in the ladle, and 5 kg of liquid sulfur is mixed and stirred.

[0051] (3) The sulfurized nickel-iron water is slowly poured into the black powder solution, and stirring is continued during the pouring process to prevent boiling.

[0052] (4) Add concentrated sulfuric acid to pH = 0.5, maintain the temperature at 80°C for 1h.

[0053] (5) Continue to add black powder to the solution until the pH is adjusted to 3, and filter.

[0054] (6) Add sodium carbonate to the solution until the pH is adjusted to 5, and filter.

[0055] (7) The nickel-cobalt-manganese concentration is adjusted to a molar ratio of 8:1:1, and the 811 precursor is synthesized by coprecipitation reaction. After washing and drying, the precursor yield is 74 kg. The leaching rates of nickel, cobalt and manganese are all more than 99%, the prepared ternary precursor is spherical particle, the particle size D50 is 10.44 μm, and the specific surface area is 11.58 m 2 / g.

[0056] Example 3

[0057] A method for preparing a ternary precursor by combined treatment of nickel-iron water and battery black powder according to the embodiment comprises the following steps:

[0058] (1) Compared with example 1, the mass of nickel-iron water discharged from the smelting furnace is changed from 100 kg to 50 kg (the mass ratio of liquid sulfur to nickel-iron water is 1:5), and other conditions remain unchanged.

[0059] (2) The 811 precursor is synthesized by coprecipitation reaction, and after washing and drying, the precursor yield is 135 kg. The leaching rates of nickel, cobalt and manganese are all more than 98%, the prepared ternary precursor is spherical particle, the particle size D50 is 10.17 μm, and the specific surface area is 10.64 m 2 / g.

[0060] Example 4

[0061] A method for preparing a ternary precursor by combined treatment of nickel-iron water and battery black powder according to the embodiment comprises the following steps:

[0062] (1) Compared with Example 1, the mixing and stirring with 10 kg of liquid sulfur is changed to the mixing and stirring with 5 kg of liquid sulfur (the mass ratio of liquid sulfur to nickel-iron melt is 1:20), the ratio of nickel-iron melt to sulfur source is changed, and other conditions remain unchanged.

[0063] (2) The 811 precursor is synthesized by a coprecipitation reaction, and after washing and drying, the precursor yield is 141 kg. The leaching rates of nickel, cobalt and manganese are all more than 97%, the prepared ternary precursor is a spherical particle, the particle size D50 is 12.43 μm, and the specific surface area is 10.17 m 2 / g.

[0064] Comparative Example 1

[0065] The method for preparing a ternary precursor from battery black powder in the present comparative example comprises the following steps:

[0066] (1) 3.2 tons of clean water are put into a reaction kettle, 400 kg of black powder is put in, stirred uniformly, and then concentrated sulfuric acid is slowly put in to adjust the pH to 3.

[0067] (2) 200 kg of hydrogen peroxide solution is added to the black powder solution as a reducing agent.

[0068] (3) Concentrated sulfuric acid is added to pH=0.5, and the temperature is maintained at 80°C for 2h.

[0069] (4) Continue to add black powder to the solution, adjust the pH to 3, and filter.

[0070] (5) Add sodium carbonate to the solution until the pH is adjusted to 5, and filter.

[0071] (6) Additional 47.3 kg of nickel sulfate crystals are supplemented, the concentrations of nickel, cobalt and manganese are matched to 8:1:1, the 811 precursor is synthesized by a coprecipitation reaction, and after washing and drying, the precursor yield is 145 kg. The leaching rates of nickel, cobalt and manganese are all more than 99%, the prepared ternary precursor is a spherical particle, the particle size D50 is 10.64 μm, and the specific surface area is 11.65 m 2 / g.

[0072] Comparative Example 2

[0073] The method for preparing a ternary precursor by combined treatment of nickel-iron melt and battery black powder in the present comparative example comprises the following steps

[0074] (1) Compared with Example 1, the same content of nickel sulfide crystals is used instead of the nickel-iron melt after sulfidation, and other conditions remain unchanged.

[0075] (2) The 811 precursor was synthesized by co-precipitation reaction. After washing and drying, the precursor yield was 125 kg. The leaching rates of nickel, cobalt and manganese were all more than 96%. The prepared ternary precursor was irregular particles with a particle size D50 of 13.91 μm and a specific surface area of 8.34 m 2 / g.

[0076] Comparative Example 3

[0077] The method for preparing a ternary precursor by jointly treating a nickel-iron molten water and a battery black powder in the present comparative example comprises the following steps

[0078] (1) Compared with Example 1, the mass of the nickel-iron molten water discharged from the smelting furnace was changed from 100 kg to 20 kg (the mass ratio of liquid sulfur to nickel-iron molten water was 1:2), and other conditions were unchanged.

[0079] (2) The 811 precursor was synthesized by co-precipitation reaction. After washing and drying, the precursor yield was 117 kg. The leaching rates of nickel, cobalt and manganese were all more than 96%. The prepared ternary precursor was irregular particles with a particle size D50 of 14.71 μm and a specific surface area of 7.34 m 2 / g.

[0080] Material Element Nickel Iron Alloy 811 Precursor Sulfur Hydrogen Peroxide Nickel Sulfate Crystal Price / $ kg 66 10 271 2 2 34

[0081] Example 1 is the standard preparation method of the present application. Compared with Example 1, the amount of the original reactant is changed to 0.5 times in Example 2, and the corresponding precursor product is also about 0.5 times, which shows that changing the amount of the reactant has little effect on the reaction.

[0082] Comparing Example 1 with Comparative Example 1, Comparative Example 1 does not use nickel-iron molten water, but directly uses black powder leaching to prepare the precursor. In the reaction process, a reducing agent hydrogen peroxide is additionally added, nickel sulfate crystals are additionally added to supplement the nickel source, and the reaction time is longer. According to the calculation, according to the synthesis of 10 kg of precursor per 100 kg of nickel-iron molten water, the price of the ternary precursor prepared from the nickel-iron molten water is 2.7 times that of the nickel-iron alloy; under the same raw material conditions, the auxiliary material cost of Example 1 is 1020 yuan, and the auxiliary material cost of Comparative Example 1 is 2008 yuan. Compared with Comparative Example 1, the auxiliary material cost of Example 1 is saved by 50%. Most importantly, Example 1 can react for 1 h at 80℃, while Comparative Example 1 needs a longer reaction time of 2 h because it does not add high-temperature nickel-iron molten water. The reaction rate of Example 1 is twice the normal rate. The nickel in the nickel-iron molten water in Example 1 provides a nickel source for the low-grade black powder, while Comparative Example 1 does not have nickel-iron molten water, and cannot reach the nickel content, and needs to add an additional nickel source.

[0083] Comparing Example 1 and Example 4, when the ratio of nickel-iron water and sulfur source is changed from 10:1 to 20:1, the yield of the precursor is reduced by 3.4%, the leaching rate of nickel, cobalt and manganese is reduced by 2%, the particle size D50 is increased by 18%, and the specific surface area is reduced by 13.4%.

[0084] Comparing Example 1, Example 3 and Comparative Example 3, when the mass ratio of black powder and nickel-iron water is changed from 4:1 to 8:1, the yield of the precursor is reduced by 7.5%, the leaching rate of nickel, cobalt and manganese is reduced by 1%, the particle size D50 is increased by 3.4%, and the specific surface area is reduced by 9%; when the mass ratio of black powder and nickel-iron water is changed from 4:1 to 20:1, which is not within the scope of the present application, the yield of the precursor is reduced by 19.9%, the leaching rate of nickel, cobalt and manganese is reduced by 3%, the particle size D50 is increased by 39.7%, the specific surface area is reduced by 37%, and the shape is changed from spherical to irregular particles.

[0085] Comparing Example 1 and Comparative Example 2, when the sulfided nickel-iron water is replaced by sulfided nickel crystals with the same content of nickel, the yield of the precursor is reduced by 14.4%, the leaching rate of nickel, cobalt and manganese is reduced by 3%, the particle size D50 is increased by 32.1%, the specific surface area is reduced by 38.8%, and the shape is changed from spherical to irregular particles. When the sulfided nickel crystals participate in the reaction, side reactions are easily generated to form trivalent hydroxyl sulfide high nickel, which affects the subsequent generation of divalent nickel ternary precursor, resulting in a decrease in various properties. In the nickel-iron water mixed system, iron will preferentially react with oxygen, and nickel will not generate trivalent nickel, so it will not cause the loss of nickel side reactions.

Claims

1. A method for preparing ternary precursors by co-processing nickel-iron molten metal and battery black powder, characterized in that: The battery black powder is dissolved in dilute acid to obtain a black powder solution; the nickel-iron water is slowly added to the black powder solution after sulfidation, and acid solution is added for leaching, the pH of the leaching endpoint is controlled by using battery black powder and / or battery black powder leaching residue during the leaching process, after the leaching is completed, hydrolysis and impurity removal are carried out, and then the nickel-cobalt-manganese ratio is adjusted, and a nickel-cobalt-manganese ternary precursor is obtained by hydrolysis co-precipitation; the nickel-iron water is high-temperature nickel-iron water produced by pyrometallurgical process, with a temperature of 1300-1500℃ and a nickel content of 5-15%; the mass ratio of the sulfur source used in the sulfidation process to the nickel-iron water is 1:(5-20); the pH of the black powder solution is 2-4, and the solid-liquid ratio is 1kg:5-10L.

2. The method according to claim 1, wherein the battery black powder is waste nickel-cobalt-manganese ternary battery positive material black powder, with a nickel content of 5-30%, a cobalt content of 1-10%, and a manganese content of 1-10%. The mass ratio of the battery black powder to the nickel-iron water in the black powder solution is (1-10):

1.

3. The method for preparing ternary precursors by combined treatment of ferronickel slag and battery black according to claim 2, characterized in that: The pH of the leaching endpoint is 2-4.

4. The method for preparing ternary precursors by combined treatment of ferronickel slag and battery black according to claim 2, characterized in that:

5. The method according to claim 1, wherein solid sulfur and / or liquid sulfur are used as the sulfur source in the sulfidation process. The leaching conditions are: temperature 50-90℃, initial pH 0.5-1.

5.

6. The method for preparing ternary precursors by combined treatment of ferronickel slag and battery black according to claim 1, characterized in that: The hydrolysis co-precipitation conditions are: temperature 60-80℃, pH 10-11.

7. The method according to claim 1, wherein the method is characterized by: The hydrolysis and impurity removal conditions are: pH 4-6.

8. The method for preparing ternary precursors by combined treatment of ferronickel slag and battery black according to claim 1, characterized in that: ​

Images