High purity tiered recovery method and system for ternary materials based on leaching extraction

Abstract

The application provides a ternary material high-purity gradient recovery method and system based on leaching extraction, relates to the technical field of waste battery material recovery, and comprises the following steps: heat treating waste ternary material to separate organic bonding components from metal oxides; then, a segmented leaching process is adopted, the endpoint of the first leaching section is controlled by monitoring the cobalt-nickel ion concentration increment, a first leaching solution containing cobalt and nickel and a first leaching residue are obtained, the first leaching residue is continuously leached to obtain a second leaching solution containing manganese; then, according to the cobalt-nickel ion concentration and the hydrogen ion concentration in the first leaching solution, the extraction equilibrium constant and the coordination saturation capacity are combined to accurately calculate the extraction agent ratio and the dosing amount for extraction separation; the organic phase after extraction is back-extracted to obtain a crude cobalt solution, and whether selective secondary extraction is performed to obtain a high-purity cobalt solution is determined by detecting the purity; finally, the aqueous phase is subjected to segmented precipitation to recover nickel. The application realizes efficient gradient separation of cobalt, nickel and manganese, and improves the metal recovery purity and the resource utilization rate.

Description

Technical Field

[0001] This invention relates to the field of waste battery material recycling technology, and in particular to a high-purity cascade recycling method and system for ternary materials based on leaching extraction. Background Technology

[0002] With the rapid development of the new energy vehicle industry, ternary lithium batteries have become the mainstream power battery widely used. Ternary materials are mainly composed of three metallic elements: nickel, cobalt, and manganese. These metal resources have high economic value and strategic significance. However, as a large number of power batteries reach the end of their service life, the recycling of waste ternary materials has become increasingly prominent. Improper handling of these waste materials not only wastes resources but also causes serious environmental pollution. Therefore, developing efficient and environmentally friendly ternary material recycling technologies is of significant economic and environmental importance.

[0003] Traditional methods for recycling ternary materials mainly fall into two categories: pyrometallurgy and hydrometallurgy. Pyrometallurgy processes spent batteries through high-temperature incineration, but this method is energy-intensive, polluting, and has a low metal recovery rate. Hydrometallurgy, on the other hand, recovers valuable metals through chemical methods such as acid leaching, extraction, and precipitation, making it relatively more environmentally friendly and efficient. Currently, hydrometallurgical recycling technology has become the mainstream approach, but many technical challenges still need to be addressed in practical applications. Summary of the Invention

[0004] The present invention provides a method and system for high-purity graded recovery of ternary materials based on leaching extraction, which can solve the problems in the prior art.

[0005] A first aspect of the present invention, A high-purity cascade recovery method for ternary materials based on leaching extraction is provided, including: Waste ternary materials are obtained, and by controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material. The material to be processed is leached in stages. The concentrations of cobalt ions and nickel ions are collected, and the concentration increments at multiple consecutive time points are calculated. When the concentration increments are lower than the rate threshold, the first leaching stage is terminated, resulting in a first leaching solution and a first leaching residue containing cobalt and nickel. The first leaching residue is then subjected to a second leaching stage reaction to obtain a second leaching solution containing manganese. Manganese precipitate is then obtained from the precipitate. The concentrations of cobalt ions, nickel ions, and hydrogen ions in the first leachate are detected, and the extractant ratio is determined. The amount of extractant added is calculated based on the hydrogen ion concentration and the extraction equilibrium constant, combined with the coordination saturation capacity. The first organic phase and the first aqueous phase are obtained by extraction. The crude cobalt solution was obtained by the first organic reverse extraction. The purity was tested and the ratio of cobalt ion concentration to impurity ion concentration was calculated. When the ratio was lower than the threshold, it was returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction partition ratio difference was calculated to determine the amount of selective extractant to be added for a second extraction to obtain a cobalt solution. The concentrations of nickel and manganese ions in the first aqueous phase were measured, and the pH ranges for the two segments were calculated based on the solubility product constant. Nickel precipitate was obtained by fractional precipitation.

[0006] By controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material, including: Based on the initial moisture content and organic component content of the waste ternary material, the drying energy consumption coefficient is calculated, the drying temperature and time are determined, and the waste ternary material is dried to obtain dried material. Based on the thermal decomposition temperature range of the organic binder component in the dried material and the oxidation critical temperature of the metal oxide component, the temperature difference is calculated to determine the pyrolysis temperature gradient and heating rate. During the pyrolysis process, the oxygen concentration in the furnace and the carbon dioxide concentration in the exhaust gas are monitored in real time, and the flow rate and composition of the introduced atmosphere are dynamically adjusted. When the carbon dioxide concentration reaches a maximum value, it is determined that the organic component decomposition is complete, and the oxygen concentration is reduced to the inert protection range to obtain the pyrolyzed material. Based on the magnetic characteristic parameters of the current collector metal in the pyrolysis material, the magnetic field strength and magnetic separation speed of the magnetic separator are determined, and the pyrolysis material is separated by magnetic separation to obtain the current collector metal component and the non-magnetic component. The non-magnetic component is collected as the processed material.

[0007] The material to be processed is leached in stages. Cobalt ion concentration and nickel ion concentration are collected, and the concentration increments at multiple consecutive time points are calculated. The first leaching stage is terminated when the concentration drops below a rate threshold, resulting in a first leaching solution and a first leaching residue containing cobalt and nickel, comprising: The elemental contents of cobalt, nickel, and manganese in the treated material were detected, and polynomial fitting was performed on the dissolution rate data of cobalt, nickel, and manganese metal oxides at different hydrogen ion concentrations to construct a correlation function between the leaching rate of cobalt, nickel, and manganese and the hydrogen ion concentration, thus obtaining the cobalt-nickel joint leaching rate function and the manganese leaching rate function. The difference between them at each hydrogen ion concentration point was calculated, and the hydrogen ion concentration corresponding to the largest difference was selected as the target hydrogen ion concentration. The dosage of the leaching agent was determined in combination with the mass of the treated material. The treated material was mixed with the prepared leaching agent and the first leaching stage reaction was carried out. During the reaction in the first leaching stage, leachate samples are collected at fixed intervals, and the concentration values ​​of cobalt ions and nickel ions are detected. The cobalt ion concentration values ​​obtained from multiple consecutive samplings are selected, and the instantaneous leaching rates of cobalt ions and nickel ions are calculated using the three-point difference method. When the instantaneous leaching rates are all lower than the corresponding rate thresholds, the cobalt and nickel leaching is determined to be complete. The reaction in the first leaching stage is then terminated, and solid-liquid separation is performed to obtain the first leaching solution and the first leaching residue containing cobalt and nickel.

[0008] The concentrations of cobalt ions, nickel ions, and hydrogen ions in the first leachate are detected, and the extractant ratio is determined. Based on a comparison of the hydrogen ion concentration and the extraction equilibrium constant, and combined with the coordination saturation capacity, the extractant dosage is calculated. Extraction yields a first organic phase and a first aqueous phase, comprising: The first leachate was sampled, and its cobalt ion concentration, nickel ion concentration, and hydrogen ion concentration were measured. Based on the hydrogen ion concentration, combined with the Nernst equation and introducing a competitive extraction coefficient correction term, a set of mass conservation equations and a set of phase equilibrium equations for cobalt-nickel bicomponent competitive extraction are established. By solving these equations simultaneously, the ratio of the main extractant to the co-extractant is obtained. Substituting the cobalt ion concentration and the nickel ion concentration into the ratio relationship, the mass ratio between the extractant components is obtained. The coordination saturation capacity is coupled with the set comparison parameters to construct a ternary constraint equation that includes the extractant dosage, organic phase volume, and aqueous phase volume. An extraction kinetic rate constant is introduced to establish a differential equation between the extraction completion degree and the extractant concentration gradient. The evolution curve of the extractant concentration over time is obtained by solving the numerical integration method. The extractant concentration corresponding to the inflection point of the extraction curve is taken as the optimal dosage concentration, and the extractant dosage is calculated. The extractant dosage is mixed according to the mass ratio and added to the first leachate for extraction reaction. After standing and separating into layers, the first organic phase and the first aqueous phase are obtained.

[0009] By coupling the coordination saturation capacity with a set ratio parameter, a ternary constraint equation is constructed, incorporating the extractant dosage, organic phase volume, and aqueous phase volume. An extraction kinetic rate constant is introduced, and a differential equation is established between the extraction completion degree and the extractant concentration gradient, including: The number of coordination active sites and steric hindrance coefficients in the extractant molecule are determined, and the theoretical coordination capacity of a single extractant molecule is calculated. Extraction equilibrium data under different extractant concentrations were collected. The extractant concentration and the corresponding metal ion extraction amount were substituted into the mass balance equation. The actual coordination saturation capacity was obtained by iterative solution, and the coordination efficiency correction factor was calculated. Based on the initial concentration of the target metal ions in the aqueous phase to be treated and the set target value of extraction completion, the total amount of metal ions that need to be coordinated is calculated. The coordination efficiency correction factor and the actual coordination saturation capacity are substituted into the material balance equation to establish a ternary constraint equation between the amount of extractant added, the volume of the organic phase, and the volume of the aqueous phase. Under different temperatures and stirring rates, the curves of metal ion concentration versus time were calculated. The differential processing was performed to obtain the relationship between the extraction rate and time. Combined with the extractant concentration gradient data, the extraction kinetic rate constant was obtained by fitting. The extraction kinetic rate constant, extractant concentration gradient, and extraction completion degree were used to construct a differential equation.

[0010] The crude cobalt solution obtained by the first organic back-extraction is tested for purity and the ratio of cobalt ion concentration to impurity ion concentration is calculated. When the ratio is lower than the threshold, the system is returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction partition ratio difference is calculated to determine the dosage of selective extractant for a second extraction. The cobalt solution is obtained by back-extraction again, including: The first organic phase was subjected to back-extraction reaction. After phase separation, a crude cobalt solution was obtained, and the ratio of cobalt ion concentration to the concentration of each impurity ion was calculated. The heat of complexation reaction of the crude cobalt solution and the selective extractant at different hydrogen ion concentrations was determined by calorimetry. The difference in enthalpy change of complexation reaction between cobalt ions and impurity ions was calculated, and a curve of its change with hydrogen ion concentration was plotted. The hydrogen ion concentration corresponding to the peak of the curve was extracted as the control point. The crude cobalt solution is returned to the extraction system, and an acid-base regulator is added to adjust the hydrogen ion concentration to the control point value. Selective extractant was added in batches, and the mixture was subjected to shaking extraction and allowed to stand for separation. The absorbance of the cobalt complex in the organic phase and the concentration of cobalt ions in the aqueous phase were determined by spectrophotometry. When the increase in absorbance was less than the increment threshold and the concentration of cobalt ions in the aqueous phase was less than the concentration threshold, the total amount of selective extractant added from each batch was accumulated and added to the extraction system to complete the secondary extraction. After standing for separation, the second organic phase was obtained. The second organic phase was then back-extracted to obtain a cobalt solution.

[0011] The concentrations of nickel and manganese ions in the first aqueous phase were measured, and the two pH ranges were calculated using the solubility product constant. The nickel precipitate was obtained through fractional precipitation, including: Take the first aqueous phase sample, measure the nickel ion concentration and manganese ion concentration, calculate their concentration ratio, and substitute the corresponding solubility product constant into the equilibrium calculation to obtain the corresponding hydroxide ion concentration at which manganese ions are completely precipitated and nickel ions begin to precipitate. Convert the corresponding pH value through the ion product constant to obtain the first numerical range. An alkaline precipitant is added to the first aqueous phase to adjust the pH value to the first value range, and solid-liquid separation is performed to obtain manganese precipitate and first filtrate. The concentration of nickel ions in the first filtrate is measured, and the concentration and the solubility product constant of nickel ions and hydroxide are substituted into the equilibrium calculation to obtain the pH value at which nickel ions are completely precipitated. A second numerical range is determined, and an alkaline precipitant is added to the first filtrate to adjust the pH value to the second numerical range. Solid-liquid separation is then performed to obtain high-purity nickel precipitate.

[0012] A second aspect of the present invention provides a high-purity cascade recovery system for ternary materials based on leaching extraction, comprising: The first unit is used to obtain waste ternary materials. By controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material. The second unit is used to leach the processed material in stages, collect the concentration of cobalt ions and nickel ions, and calculate the concentration increment at multiple consecutive time points. When the concentration increment is lower than the rate threshold, the first leaching stage is terminated to obtain a first leaching solution and a first leaching residue containing cobalt and nickel. The first leaching residue is then subjected to a second leaching stage reaction to obtain a second leaching solution containing manganese, which is then precipitated to obtain manganese precipitate. The third unit is used to detect the cobalt ion concentration, nickel ion concentration and hydrogen ion concentration of the first leachate, and determine the extractant ratio. Based on the hydrogen ion concentration and the extraction equilibrium constant, the extractant dosage is calculated in combination with the coordination saturation capacity to extract the first organic phase and the first aqueous phase. The fourth unit is used to perform the first organic reverse extraction to obtain a crude cobalt solution, detect its purity and calculate the ratio of cobalt ion concentration to impurity ion concentration. When the ratio is lower than the threshold, it is returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction distribution ratio difference is calculated to determine the amount of selective extractant to be added for a second extraction to obtain a cobalt solution. The fifth unit is used to detect the concentrations of nickel and manganese ions in the first aqueous phase, calculate the two pH ranges using the solubility product constant, and obtain nickel precipitate through segmented precipitation.

[0013] A third aspect of the present invention, An electronic device is provided, comprising: processor; Memory used to store processor-executable instructions; The processor is configured to invoke instructions stored in the memory to execute the aforementioned method.

[0014] Fourth aspect of the embodiments of the present invention, A computer-readable storage medium is provided, having stored thereon computer program instructions that, when executed by a processor, implement the aforementioned method.

[0015] The beneficial effects of this application are as follows: This invention employs a segmented leaching method and dynamic monitoring of concentration increments. By setting a rate threshold to precisely control the leaching endpoint, it achieves efficient separation of cobalt, nickel, and manganese, avoiding energy waste and cross-contamination caused by excessive leaching. At the same time, by calculating the extraction distribution ratio and coordination saturation capacity, it precisely controls the amount of extractant, improving extraction selectivity and economy.

[0016] This invention establishes a purity control system based on ion concentration ratio judgment and solubility product constant calculation. When the purity of the cobalt solution does not meet the standard, it can be returned to the extraction system for secondary extraction. By adjusting the hydrogen ion concentration and the use of selective extractant, the deep removal of impurities is achieved, and high-purity cobalt, nickel and manganese products are obtained. This realizes the cascade recovery and resource utilization of valuable metals in ternary materials. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the process for a high-purity cascade recovery method of ternary materials based on leaching extraction, according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a process for thermally decomposing waste ternary materials. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0020] Figure 1 This is a schematic diagram of the process for a high-purity cascade recovery method of ternary materials based on leaching extraction, as described in an embodiment of the present invention. Figure 1 As shown, the method includes: Waste ternary materials are obtained, and by controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material. The material to be processed is leached in stages. The concentrations of cobalt ions and nickel ions are collected, and the concentration increments at multiple consecutive time points are calculated. When the concentration increments are lower than the rate threshold, the first leaching stage is terminated, resulting in a first leaching solution and a first leaching residue containing cobalt and nickel. The first leaching residue is then subjected to a second leaching stage reaction to obtain a second leaching solution containing manganese. Manganese precipitate is then obtained from the precipitate. The concentrations of cobalt ions, nickel ions, and hydrogen ions in the first leachate are detected, and the extractant ratio is determined. The amount of extractant added is calculated based on the hydrogen ion concentration and the extraction equilibrium constant, combined with the coordination saturation capacity. The first organic phase and the first aqueous phase are obtained by extraction. The crude cobalt solution was obtained by the first organic reverse extraction. The purity was tested and the ratio of cobalt ion concentration to impurity ion concentration was calculated. When the ratio was lower than the threshold, it was returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction partition ratio difference was calculated to determine the amount of selective extractant to be added for a second extraction to obtain a cobalt solution. The concentrations of nickel and manganese ions in the first aqueous phase were measured, and the pH ranges for the two segments were calculated based on the solubility product constant. Nickel precipitate was obtained by fractional precipitation.

[0021] Figure 2 This is a schematic diagram of a process for thermally decomposing waste ternary materials. In one optional embodiment, by controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material, including: Based on the initial moisture content and organic component content of the waste ternary material, the drying energy consumption coefficient is calculated, the drying temperature and time are determined, and the waste ternary material is dried to obtain dried material. Based on the thermal decomposition temperature range of the organic binder component in the dried material and the oxidation critical temperature of the metal oxide component, the temperature difference is calculated to determine the pyrolysis temperature gradient and heating rate. During the pyrolysis process, the oxygen concentration in the furnace and the carbon dioxide concentration in the exhaust gas are monitored in real time, and the flow rate and composition of the introduced atmosphere are dynamically adjusted. When the carbon dioxide concentration reaches a maximum value, it is determined that the organic component decomposition is complete, and the oxygen concentration is reduced to the inert protection range to obtain the pyrolyzed material. Based on the magnetic characteristic parameters of the current collector metal in the pyrolysis material, the magnetic field strength and magnetic separation speed of the magnetic separator are determined, and the pyrolysis material is separated by magnetic separation to obtain the current collector metal component and the non-magnetic component. The non-magnetic component is collected as the processed material.

[0022] In the processing of waste ternary materials, for waste ternary materials with a moisture content of 8% and an organic component content of 12%, the calculation of its drying energy consumption coefficient needs to comprehensively consider parameters such as the initial moisture content, organic component content, and specific heat capacity of the material. When the initial moisture content is 8%, the specific heat capacity of the material (1.2 kJ / kg / °C) is multiplied by the moisture content value, and then divided by the latent heat of vaporization of standard moisture (2.26 MJ / kg), resulting in a drying energy consumption coefficient of 0.042. Based on this coefficient, the drying temperature is determined to be 110°C, and the drying time is 3 hours. Under these conditions, the waste ternary materials are placed in a hot air circulating dryer for processing. The hot air velocity inside the equipment is controlled at 2 m / s, and the material thickness does not exceed 30 mm to ensure uniform heat transfer. During the drying process, the material is turned over every 30 minutes to ensure uniform heating. After processing, the moisture content of the material is measured to be below 1.5%, obtaining dried material that meets the requirements of subsequent processes.

[0023] The organic binder components in the dried material mainly include polymers such as polyvinylidene fluoride and sodium carboxymethyl cellulose, whose thermal decomposition temperature ranges from 280°C to 450°C. Among the metal oxide components, the critical oxidation temperature of nickel, cobalt, and manganese oxides is 520°C. Exceeding this temperature will cause valence state changes, affecting subsequent recovery efficiency. Comparing the critical oxidation temperature of 520°C with the upper limit of the thermal decomposition range of 450°C yields a temperature difference of 70°C. Based on this temperature difference, the pyrolysis temperature gradient is set to three stages: the first stage is from room temperature to 280°C at a heating rate of 5°C per minute, held for 20 minutes; the second stage is from 280°C to 380°C at a heating rate reduced to 3°C per minute, held for 40 minutes; and the third stage is from 380°C to 450°C at a heating rate of 2°C per minute, held for 30 minutes.

[0024] The pyrolysis process takes place in a tubular furnace. Each batch of material is loaded with 5 kg of material at a density controlled at 0.8 g / cm³. The initial atmosphere is a mixture of nitrogen and air, with nitrogen comprising 75% by volume and air 25% by volume, at a total flow rate of 800 mL / min. An oxygen concentration sensor is installed at the furnace inlet, measuring from 0 to 25% by volume with an accuracy of 0.1% by volume. An infrared carbon dioxide concentration detector is installed at the exhaust, measuring from 0 to 10000 ppm with a response time of less than 5 seconds. When the furnace temperature reaches 280°C, the carbon dioxide concentration begins to rise, gradually increasing from an initial 450 ppm, reaching 3200 ppm at 320°C. At this point, the air flow rate is increased to 35% of the total flow rate to ensure complete oxidation and decomposition of the organic components. As the temperature continues to rise to 380°C, the carbon dioxide concentration reaches a peak of 6800 ppm, while the oxygen concentration remains at 6.5% by volume. During the continued heat preservation process, the carbon dioxide concentration began to decrease. When the temperature stabilized at 450 degrees Celsius and was kept at that temperature for 20 minutes, the carbon dioxide concentration dropped to 1200 ppm. Moreover, the concentration change was less than 50 ppm within 10 consecutive minutes. This point was determined to be the maximum value point at which the organic components had been completely decomposed.

[0025] After the organic components have decomposed, the atmosphere composition is immediately adjusted. The nitrogen flow rate is increased to 95% of the total flow rate, while the air flow rate is reduced to 5%. This reduces the oxygen concentration in the furnace from 6.5% by volume to 1.2% by volume, entering the inert protection range. This oxygen concentration effectively prevents further oxidation of the metal oxides and avoids reduction reactions. After maintaining the temperature for another 15 minutes under inert atmosphere protection, the heating system is turned off, and the nitrogen flow rate is maintained at 600 ml / min. The material is allowed to cool naturally in the furnace to below 80 degrees Celsius before being removed, yielding pyrolysis material. The pyrolysis material is a dark brown powder with an average particle size of 50 micrometers. The current collector metals are mainly copper and aluminum, accounting for approximately 35% by mass.

[0026] The current collector metal copper is diamagnetic, with a magnetic susceptibility of -9.63 x 10⁻⁶. In contrast, the ferromagnetic impurities mixed in the pyrolysis material have magnetic susceptibility hundreds of times higher. Aluminum is also diamagnetic, with a magnetic susceptibility of -2.1 x 10⁻⁵. Based on these differences in magnetic characteristics, a permanent magnet drum separator was selected for separation. The magnetic field strength was set to 1200 Gauss, which effectively adsorbs ferromagnetic impurities without affecting the copper-aluminum composition. The magnetic drum has a diameter of 400 mm and a rotation speed of 30 revolutions per minute, corresponding to a linear velocity of 0.628 m / s. The pyrolysis material is uniformly fed into the feed hopper of the magnetic separator at a rate of 150 kg / h. Under the combined action of gravity and magnetic force, the material moves along the drum surface. The ferromagnetic component is adsorbed onto the drum surface and, as the drum rotates to the discharge area, detaches at the point where the magnetic field strength weakens, collecting as the current collector metal component. The non-magnetic components, including copper powder, aluminum powder, and metal oxide particles, maintain their original trajectories under the influence of a magnetic field and are discharged from the bottom outlet of the magnetic separator. The magnetic separation process is continuous, and the magnetic field strength is controlled within the range of 1150 to 1250 Gauss to ensure stable separation results. The mass of the non-magnetic components after magnetic separation is approximately 3.25 kg, of which the purity of the metal oxides reaches over 92%. These components are then used as processed material in subsequent hydrometallurgical or pyrometallurgical processes for metal element recovery.

[0027] In one optional embodiment, the material to be processed is leached in stages, the concentrations of cobalt ions and nickel ions are collected, and the concentration increments at multiple consecutive time points are calculated. When the concentration increments fall below a rate threshold, the first leaching stage is terminated, resulting in a first leaching solution and a first leaching residue containing cobalt and nickel, comprising: The elemental contents of cobalt, nickel, and manganese in the treated material were detected, and polynomial fitting was performed on the dissolution rate data of cobalt, nickel, and manganese metal oxides at different hydrogen ion concentrations to construct a correlation function between the leaching rate of cobalt, nickel, and manganese and the hydrogen ion concentration, thus obtaining the cobalt-nickel joint leaching rate function and the manganese leaching rate function. The difference between them at each hydrogen ion concentration point was calculated, and the hydrogen ion concentration corresponding to the largest difference was selected as the target hydrogen ion concentration. The dosage of the leaching agent was determined in combination with the mass of the treated material. The treated material was mixed with the prepared leaching agent and the first leaching stage reaction was carried out. During the reaction in the first leaching stage, leachate samples are collected at fixed intervals, and the concentration values ​​of cobalt ions and nickel ions are detected. The cobalt ion concentration values ​​obtained from multiple consecutive samplings are selected, and the instantaneous leaching rates of cobalt ions and nickel ions are calculated using the three-point difference method. When the instantaneous leaching rates are all lower than the corresponding rate thresholds, the cobalt and nickel leaching is determined to be complete. The reaction in the first leaching stage is then terminated, and solid-liquid separation is performed to obtain the first leaching solution and the first leaching residue containing cobalt and nickel.

[0028] Before the staged leaching of the treated material, the elemental content needs to be analyzed. Inductively coupled plasma atomic emission spectrometry (ICP-AES) is used to analyze the material and accurately determine the mass percentage content of cobalt, nickel, and manganese. Specifically, 0.5 g of the treated material sample is weighed and placed in a polytetrafluoroethylene (PTFE) digestion vessel. Aqua regia is added for microwave digestion at 180°C for 30 minutes. After digestion, the solution is transferred to a volumetric flask, diluted to 100 mL with deionized water, and then analyzed using a spectrometer. Comparison with a standard solution revealed that the treated material contained 12.3% cobalt, 8.7% nickel, and 35.6% manganese.

[0029] To establish the correlation between leaching rate and hydrogen ion concentration, a series of leaching agent solutions with different hydrogen ion concentrations were prepared, ranging from 0.5 mol / L to 4.0 mol / L, with concentration points set at 0.5 mol / L intervals. Under each hydrogen ion concentration condition, 5 grams of the material to be treated were weighed, and 100 ml of leaching agent was added. Leaching experiments were conducted in a constant-temperature water bath at 60 degrees Celsius. Samples were taken every 10 minutes during the leaching process, for a total of 6 samples. The concentrations of cobalt, nickel, and manganese ions in the leachate were determined using atomic absorption spectrometry. The leaching rate data of each element under different hydrogen ion concentrations were calculated by analyzing the changes in concentration over time.

[0030] The obtained leaching rate data were subjected to polynomial fitting, with hydrogen ion concentration as the independent variable and the leaching rates of cobalt, nickel, and manganese as the dependent variables. A cubic polynomial was used for data fitting, and the least squares method was employed to determine the polynomial coefficients, minimizing the sum of squares of the deviations between the fitted curve and the experimental data points. The fitting yielded leaching rate functions for cobalt, nickel, and manganese. Since cobalt and nickel are target recovery elements, the cobalt leaching rate was added to the nickel leaching rate to obtain the cobalt-nickel combined leaching rate function.

[0031] The optimal leaching conditions were determined by calculating the difference between the cobalt-nickel co-leaching rate and the manganese leaching rate at various hydrogen ion concentrations. At a hydrogen ion concentration of 0.5 mol / L, the cobalt-nickel co-leaching rate was 0.15 mmol / min / g, and the manganese leaching rate was 0.08 mmol / min / g, with a difference of 0.07. When the hydrogen ion concentration increased to 1.5 mol / L, the cobalt-nickel co-leaching rate rose to 0.42 mmol / min / g, while the manganese leaching rate was only 0.18 mmol / min / g, with a difference of 0.24. Further increasing the hydrogen ion concentration to 2.0 mol / L resulted in a cobalt-nickel co-leaching rate of 0.51 mmol / min / g and a manganese leaching rate of 0.19 mmol / min / g, with a difference of 0.32, reaching its maximum. When the hydrogen ion concentration was further increased to 2.5 mol / L, the cobalt-nickel leaching rate was 0.58 mmol / min / g, but the manganese leaching rate increased significantly to 0.29 mmol / min / g, and the difference decreased to 0.29. Therefore, a hydrogen ion concentration of 2.0 mol / L was selected as the target hydrogen ion concentration.

[0032] The dosage of the leaching agent is calculated based on the target hydrogen ion concentration and the mass of the material to be treated. Assuming the mass of the material to be treated is 100 kg, and sulfuric acid is chosen as the leaching agent, sulfuric acid ionizes in aqueous solution to produce hydrogen ions. The amount of sulfuric acid needed needs to be calculated based on the target hydrogen ion concentration and the liquid-to-solid ratio. A liquid-to-solid ratio of 8:1 is set, meaning 8 liters of leachate are needed per kilogram of material to be treated; therefore, 800 liters of leachate are required for 100 kg of material. To achieve a hydrogen ion concentration of 2.0 mol / L in the leachate, a total amount of hydrogen ions needs to be added of 1600 mol. Considering that sulfuric acid is a dicarboxylic acid, each mol of sulfuric acid can provide 2 mol of hydrogen ions; therefore, 800 mol of sulfuric acid is required. Using 98% concentrated sulfuric acid with a density of 1.84 g / mL, the calculated amount of concentrated sulfuric acid needed is approximately 42.4 liters. In actual operation, 700 liters of deionized water should be added to the reactor, and 42.4 liters of concentrated sulfuric acid should be added slowly while stirring. After the sulfuric acid is completely dissolved and cooled to room temperature, deionized water should be added to bring the total volume to 800 liters.

[0033] The prepared leaching agent is transferred to a reactor equipped with a stirring device and a temperature control system. It is heated to 60 degrees Celsius and kept at a constant temperature. 100 kg of the material to be treated is added in batches while stirring. The feeding process is controlled to be completed within 20 minutes to avoid agglomeration due to excessive local material concentration. After feeding is completed, the stirrer is turned on and the speed is set to 300 rpm to ensure that the material and the leaching agent are in full contact. This time is marked as the start time of the first leaching stage reaction.

[0034] A timed sampling and detection mechanism was established during the first leaching stage reaction. Leachate samples were collected every 15 minutes from the start of the reaction, with each sample being 20 ml. Sampling tubes equipped with filters were used to ensure the collected liquid samples were free of solid particles. The collected samples were rapidly cooled to room temperature, and the concentrations of cobalt and nickel ions were determined using atomic absorption spectrometry. At 15 minutes of reaction, the cobalt ion concentration was detected as 0.68 g / L and the nickel ion concentration as 0.45 g / L. At 30 minutes, the cobalt ion concentration rose to 1.32 g / L and the nickel ion concentration to 0.87 g / L. At 45 minutes, the cobalt ion concentration was 1.89 g / L and the nickel ion concentration was 1.24 g / L. At 60 minutes, the cobalt ion concentration reached 2.38 g / L and the nickel ion concentration was 1.56 g / L.

[0035] The instantaneous leaching rates of cobalt and nickel ions were calculated using the three-point difference method. Concentration data from three consecutive sampling points were selected, and the concentration change rate at the midpoint of the sampling time was taken as the instantaneous leaching rate at that moment. Specifically, the concentration value from the first sampling point was subtracted from the concentration value from the third sampling point. The resulting concentration difference was divided by the time interval between the two sampling points, and then divided by the mass of the material being treated to obtain the instantaneous leaching rate per unit mass of material. At 30 minutes, the instantaneous leaching rate of cobalt ions was 0.064 g / min / kg, and the instantaneous leaching rate of nickel ions was 0.042 g / min / kg. At 45 minutes, the instantaneous leaching rate of cobalt ions was 0.057 g / min / kg, and the instantaneous leaching rate of nickel ions was 0.037 g / min / kg.

[0036] Rate thresholds were set based on experimental experience and process requirements. The rate threshold for cobalt ions was set at 0.015 g / min / kg, and the rate threshold for nickel ions was set at 0.010 g / min / kg. When the instantaneous leaching rates of both cobalt and nickel ions were below their corresponding rate thresholds, the cobalt-nickel leaching was considered essentially complete. Continued monitoring revealed that at 90 minutes, the cobalt ion concentration was 2.94 g / L, and the nickel ion concentration was 1.93 g / L, resulting in a calculated instantaneous leaching rate of 0.019 g / min / kg for cobalt ions and 0.012 g / min / kg for nickel ions. At 105 minutes, the cobalt ion concentration was 3.12 g / L, and the nickel ion concentration was 2.05 g / L, with the instantaneous leaching rates decreasing to 0.012 g / min / kg and 0.008 g / min / kg, respectively, both below the set rate thresholds.

[0037] Once cobalt-nickel leaching is confirmed to be complete, heating is immediately stopped and the stirrer is turned off to terminate the first leaching stage reaction. The slurry in the reactor is then pumped to a solid-liquid separation device for separation. A plate and frame filter press is used for solid-liquid separation, with a filtration pressure set at 0.6 MPa and a filtration time of approximately 40 minutes. The resulting filtrate is the first leaching solution containing cobalt and nickel, with a cobalt ion concentration of 3.12 g / L, a nickel ion concentration of 2.05 g / L, and a manganese ion concentration of 1.15 g / L. After the filter cake is washed twice with deionized water, the first leaching residue is obtained. Measurements show that the cobalt content has decreased to 0.8%, the nickel content to 0.5%, while the manganese content remains at 31.2%, indicating that cobalt and nickel have been effectively leached while most of the manganese remains in the leaching residue.

[0038] In one optional embodiment, the concentrations of cobalt ions, nickel ions, and hydrogen ions in the first leachate are detected, and the extractant ratio is determined. The extractant dosage is calculated based on a comparison of the hydrogen ion concentration and the extraction equilibrium constant, combined with the coordination saturation capacity. Extraction yields a first organic phase and a first aqueous phase, comprising: The first leachate was sampled, and its cobalt ion concentration, nickel ion concentration, and hydrogen ion concentration were measured. Based on the hydrogen ion concentration, combined with the Nernst equation and introducing a competitive extraction coefficient correction term, a set of mass conservation equations and a set of phase equilibrium equations for cobalt-nickel bicomponent competitive extraction are established. By solving these equations simultaneously, the ratio of the main extractant to the co-extractant is obtained. Substituting the cobalt ion concentration and the nickel ion concentration into the ratio relationship, the mass ratio between the extractant components is obtained. The coordination saturation capacity is coupled with the set comparison parameters to construct a ternary constraint equation that includes the extractant dosage, organic phase volume, and aqueous phase volume. An extraction kinetic rate constant is introduced to establish a differential equation between the extraction completion degree and the extractant concentration gradient. The evolution curve of the extractant concentration over time is obtained by solving the numerical integration method. The extractant concentration corresponding to the inflection point of the extraction curve is taken as the optimal dosage concentration, and the extractant dosage is calculated. The extractant dosage is mixed according to the mass ratio and added to the first leachate for extraction reaction. After standing and separating into layers, the first organic phase and the first aqueous phase are obtained.

[0039] This invention enables precise extraction and separation of cobalt and nickel ions in the first leachate, employing a systematic detection and calculation method to determine the extractant ratio and dosage. In practice, a 500 mL sample was extracted from the first leachate for comprehensive analysis. Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used to determine the cobalt ion concentration to be 8.5 g / L and the nickel ion concentration to be 12.3 g / L. Simultaneously, a pH meter was used to determine the hydrogen ion concentration to be 0.15 mol / L, corresponding to a pH of 0.82. These fundamental data provide accurate input parameters for subsequent extractant ratio calculations.

[0040] After obtaining the basic data of the leachate, based on the Nernst equation, the distribution behavior of metal ions between the organic and aqueous phases during extraction was considered. A competitive extraction coefficient correction term was introduced to describe the competition between cobalt and nickel ions for the active sites of the extractant. Specifically, when the hydrogen ion concentration was 0.15 mol / L, the competition coefficient of cobalt ions for the main extractant was 2.8, while that of nickel ions was 1.6. By establishing a set of mass conservation equations, the total amount of metal ions remained constant before and after extraction; that is, the change in ion concentration in the aqueous phase was equal to the amount of ions adsorbed in the organic phase. The phase equilibrium equations described the distribution relationship between the components in the two phases when extraction reached equilibrium. At this point, there was a definite proportional relationship between the metal ion concentration in the organic phase, the metal ion concentration in the aqueous phase, and the free extractant concentration.

[0041] By simultaneously solving the mass conservation equations and the phase equilibrium equations, the ratio between the primary extractant and the co-extractant was obtained. This ratio indicates that the concentration of the primary extractant should be 3.2 times that of the co-extractant, while also considering the effects of cobalt and nickel ion concentrations. Substituting the measured cobalt ion concentrations of 8.5 g / L and nickel ion concentrations of 12.3 g / L into the ratio formula, calculations showed that the primary extractant accounted for 76.2% of the total extractant mass, and the co-extractant accounted for 23.8%.

[0042] After determining the extractant composition ratio, the precise extractant dosage needs to be calculated. Coordination saturation capacity refers to the maximum amount of metal ions that a unit mass of extractant can bind. The coordination saturation capacity is coupled with a ratio parameter, defined as the ratio of the organic phase volume to the aqueous phase volume, set to 1:3, to construct a ternary constraint equation incorporating the extractant dosage, organic phase volume, and aqueous phase volume. To obtain the optimal extractant concentration, an extraction kinetic rate constant is introduced for dynamic analysis. This rate constant reflects the rate at which metal ions transfer from the aqueous phase to the organic phase and is related to factors such as extraction temperature, stirring intensity, and interfacial area. Under experimental conditions, with the temperature controlled at 45 degrees Celsius and the stirring speed at 350 rpm, the extraction rate constant for cobalt ions is 0.082 per minute, and the extraction rate constant for nickel ions is 0.055 per minute. A differential equation is then established between the extraction completion rate and the extractant concentration gradient.

[0043] The differential equation was solved using numerical integration. The time interval was divided into several small segments, each with a time step of 0.5 minutes. Within each time step, the extraction rate was calculated based on the current extractant concentration and metal ion concentration, thus obtaining the concentration value at the next moment. Through iterative calculation, a complete evolution curve of the extractant concentration over time was obtained. The curve shows that the extractant concentration decreases rapidly in the initial stage of extraction, then the rate of decrease gradually slows down and eventually stabilizes. There is a clear inflection point on the curve. The moment corresponding to this inflection point is the critical point for the extraction reaction to transition from the rapid stage to the slow stage. The extractant concentration corresponding to the inflection point is taken as the optimal addition concentration.

[0044] The actual amount of extractant added is calculated based on the optimal concentration and the preset organic phase volume. When the volume of the first leachate is 10 liters and the ratio parameter is 1:3, the required organic phase volume is 3.33 liters. Multiplying the optimal concentration of 35 g / L by the organic phase volume of 3.33 liters, the total amount of extractant added is 116.55 g. According to the mass ratio determined above, the amount of main extractant added is 88.85 g, and the amount of co-extractant added is 27.7 g.

[0045] In the actual extraction operation, 88.85 g of the main extractant and 27.7 g of the co-extractant were added to the extraction tank, and an appropriate amount of diluent was added to make the total volume of the organic phase reach 3.33 liters, and the mixture was thoroughly mixed. The prepared extractant was added to the extraction reactor containing 10 liters of the first leachate, and the extraction reaction was carried out at 45 degrees Celsius. Mechanical stirring was used to ensure full contact between the two phases for 25 minutes. After the extraction reaction was completed, stirring was stopped, and the mixture was transferred to a separatory device to stand and separate into layers for 15 minutes. Due to the lower density of the organic phase, it was located on the upper layer to form the first organic phase, and the aqueous phase was located on the lower layer to form the first aqueous phase. The first organic phase and the first aqueous phase were collected separately by liquid-liquid separation. The first organic phase was enriched with most of the cobalt ions, while the first aqueous phase contained some nickel ions and a small amount of cobalt ions. The first aqueous phase was tested and the concentration of cobalt ions decreased to 0.8 g / L and the concentration of nickel ions decreased to 9.5 g / L. The extraction rate of cobalt reached 90.6% and the extraction rate of nickel was 22.8%, thus achieving the initial separation of cobalt and nickel.

[0046] In one optional implementation, the coordination saturation capacity is coupled with a set ratio parameter to construct a ternary constraint equation including the extractant dosage, organic phase volume, and aqueous phase volume. An extraction kinetic rate constant is introduced to establish a differential equation between the extraction completion degree and the extractant concentration gradient, including: The number of coordination active sites and steric hindrance coefficients in the extractant molecule are determined, and the theoretical coordination capacity of a single extractant molecule is calculated. Extraction equilibrium data under different extractant concentrations were collected. The extractant concentration and the corresponding metal ion extraction amount were substituted into the mass balance equation. The actual coordination saturation capacity was obtained by iterative solution, and the coordination efficiency correction factor was calculated. Based on the initial concentration of the target metal ions in the aqueous phase to be treated and the set target value of extraction completion, the total amount of metal ions that need to be coordinated is calculated. The coordination efficiency correction factor and the actual coordination saturation capacity are substituted into the material balance equation to establish a ternary constraint equation between the amount of extractant added, the volume of the organic phase, and the volume of the aqueous phase. Under different temperatures and stirring rates, the curves of metal ion concentration versus time were calculated. The differential processing was performed to obtain the relationship between the extraction rate and time. Combined with the extractant concentration gradient data, the extraction kinetic rate constant was obtained by fitting. The extraction kinetic rate constant, extractant concentration gradient, and extraction completion degree were used to construct a differential equation.

[0047] Determining the coordination saturation capacity requires analyzing the molecular structure of the extractant. Density functional theory calculations are used to obtain the charge distribution of all atoms in the molecule, identifying active sites with lone pairs of electrons or coordination capabilities, such as hydroxyl oxygen atoms, carbonyl oxygen atoms, and nitrogen atoms. For di(2-ethylhexyl)phosphate extractants, the molecule contains two phosphate groups, and the oxygen atom on each phosphate group can serve as a coordination active site. Theoretically, a single extractant molecule has four coordination sites. Molecular dynamics simulations are used to calculate the spatial conformational changes of the extractant molecule when in contact with metal ions, measuring the distance between coordination sites and the angle between them when coordinating with metal ions, determining the steric hindrance coefficient to be 0.75. Multiplying the number of coordination active sites by the steric hindrance coefficient yields a theoretical coordination capacity of three metal ions for a single extractant molecule.

[0048] The actual coordination saturation capacity was determined through a series of extraction experiments. An initial copper ion aqueous solution with a concentration of 5 g / L was prepared, and the pH was adjusted to 4.5. Organic phase solutions of extractant with concentrations of 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, and 0.5 mol / L were prepared, using kerosene as a diluent. The organic and aqueous phases were mixed at a volume ratio of 1:1 and placed in a constant-temperature shaker, shaken at 200 rpm for 30 min at 25°C. After standing and phase separation, the remaining copper ion concentration in the aqueous phase was measured using atomic absorption spectrometry. The amount of extractable organic phase was calculated based on the decrease in copper ion concentration in the aqueous phase. When the extractant concentration is 0.1 mol / L, the extraction amount of copper ions in the organic phase is 0.23 g / L; at 0.2 mol / L, the extraction amount is 0.45 g / L; at 0.3 mol / L, the extraction amount is 0.62 g / L; at 0.4 mol / L, the extraction amount is 0.75 g / L; and at 0.5 mol / L, the extraction amount is 0.81 g / L. Substituting the extractant concentration and the corresponding metal ion extraction amount into the mass balance equation for iterative calculation, and using nonlinear least squares fitting, the actual coordination saturation capacity is found to be 1.8 mol of copper ions coordinated per mole of extractant. The coordination efficiency correction factor is calculated by the ratio of the actual coordination saturation capacity to the theoretical coordination capacity, and its value is 0.6.

[0049] The ternary constraint equations are constructed based on material balance. The initial copper ion concentration in the aqueous phase is 8 g / L, and the total volume of the aqueous phase is 1000 L. The target extraction completion rate is set at 95%, meaning the copper ion concentration in the aqueous phase needs to be reduced to 0.4 g / L after extraction. This requires a total of 7.6 kg of copper ions to be transferred from the aqueous phase to the organic phase, equivalent to 119.37 mol. Considering a coordination efficiency correction factor of 0.6, the actual required extractant moles are 198.95 mol. With an extractant molecular weight of 390, the required extractant mass is 77.59 kg. There is a constraint relationship between the organic phase volume and the extractant dosage. When the extractant concentration in the organic phase is set at 0.3 mol / L, the required organic phase volume is 663.17 L. The ratio between the organic phase volume and the aqueous phase volume is also subject to practical engineering constraints. When the aqueous phase volume is 1000 L, the ratio corresponding to the organic phase volume of 663.17 L is 0.66:1. If the target extraction completion rate is changed to 98%, the amount of copper ions to be transferred increases to 7.84 kg. The corresponding amount of extractant and the volume of organic phase need to be adjusted proportionally to form a complete ternary constraint equation system.

[0050] The extraction kinetic rate constant was obtained through time-series experiments under different operating conditions. An aqueous phase with an initial copper ion concentration of 5 g / L and an organic phase with an extractant concentration of 0.3 mol / L were prepared and mixed at a volume ratio of 1:1. Samples were taken every 2 minutes at 15℃ and a stirring rate of 150 rpm to determine the copper ion concentration in the aqueous phase. Experimental data showed that the copper ion concentration in the aqueous phase was 5 g / L at 0 min, 4.2 g / L at 2 min, 3.6 g / L at 4 min, 3.2 g / L at 6 min, 2.9 g / L at 8 min, and 2.7 g / L at 10 min. The concentration change data over time were differentiated, and the rate of concentration change between adjacent time points was calculated. The extraction rate was 0.4 g / (L·min) from 0 to 2 min, 0.3 g / (L·min) from 2 to 4 min, and 0.2 g / (L·min) from 4 to 6 min. The experiment was repeated at 25℃ and a stirring rate of 200 rpm. The extraction rate was significantly improved, reaching 0.65 g / (L·min) from 0 to 2 min. The concentration gradient of the extractant at the interface between the organic and aqueous phases was recorded, and the concentration distribution of the extractant at the interface layer was determined using fluorescence tracer technology. The calculated concentration gradient was 0.05 mol / (L·mm). Substituting the extraction rate, extractant concentration gradient, and current extraction completion data into the kinetic equation for nonlinear fitting, the extraction kinetic rate constant for this system at 25℃ was found to be 0.023 L / (mol·s). A differential equation was established to describe the change in extraction completion over time. The equation includes three variables: the rate constant, the extractant concentration gradient, and the current concentration of unextracted metal ions. Solving this differential equation numerically can predict the extraction completion at any given time.

[0051] In one optional embodiment, a crude cobalt solution is obtained by first organic back-extraction. The purity is detected, and the ratio of cobalt ion concentration to impurity ion concentration is calculated. If the ratio is below a threshold, the system is returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction partition ratio difference is calculated to determine the selective extractant dosage for a second extraction. A second back-extraction is then performed to obtain the cobalt solution, comprising: The first organic phase was subjected to back-extraction reaction. After phase separation, a crude cobalt solution was obtained, and the ratio of cobalt ion concentration to the concentration of each impurity ion was calculated. The heat of complexation reaction of the crude cobalt solution and the selective extractant at different hydrogen ion concentrations was determined by calorimetry. The difference in enthalpy change of complexation reaction between cobalt ions and impurity ions was calculated, and a curve of its change with hydrogen ion concentration was plotted. The hydrogen ion concentration corresponding to the peak of the curve was extracted as the control point. The crude cobalt solution is returned to the extraction system, and an acid-base regulator is added to adjust the hydrogen ion concentration to the control point value. Selective extractant was added in batches, and the mixture was subjected to shaking extraction and allowed to stand for separation. The absorbance of the cobalt complex in the organic phase and the concentration of cobalt ions in the aqueous phase were determined by spectrophotometry. When the increase in absorbance was less than the increment threshold and the concentration of cobalt ions in the aqueous phase was less than the concentration threshold, the total amount of selective extractant added from each batch was accumulated and added to the extraction system to complete the secondary extraction. After standing for separation, the second organic phase was obtained. The second organic phase was then back-extracted to obtain a cobalt solution.

[0052] When performing back-extraction on the first organic phase, sulfuric acid solution is used as the back-extraction agent. The concentration of sulfuric acid solution is controlled in the range of 4 mol / L to 6 mol / L. The first organic phase and sulfuric acid solution are mixed at a volume ratio of 1:0.3 to 1:0.5. Back-extraction is carried out under the condition of stirring speed of 300 rpm to 500 rpm for 15 min to 25 min. After the back-extraction is completed, stirring is stopped, and the standing layer separation time is 10 min to 20 min. After the two phases are completely separated, the lower aqueous phase is separated out as the crude cobalt solution. Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used to perform multi-element analysis on the crude cobalt solution. The cobalt ion concentration was measured to be 18 g / L to 25 g / L, while the nickel ion concentration was measured to be 0.8 g / L to 1.5 g / L, the manganese ion concentration to be 0.3 g / L to 0.6 g / L, and the copper ion concentration to be 0.1 g / L to 0.2 g / L. The ratios of cobalt ion concentration to nickel ion concentration were calculated to be 15 to 20, cobalt ion concentration to manganese ion concentration to be 35 to 50, and cobalt ion concentration to copper ion concentration to be 90 to 150. Thresholds were set for the ratios of cobalt ion concentration to each impurity ion concentration: cobalt-nickel ratio ≥ 80, cobalt-manganese ratio ≥ 200, and cobalt-copper ratio ≥ 500. If any ratio in the crude cobalt solution was found to be below the corresponding threshold, it needed to be returned to the extraction system for secondary extraction and purification.

[0053] Thermodynamic tests were performed using a microcalorimeter to investigate the complexation reaction of cobalt ions and impurity ions in the crude cobalt solution with a selective extractant. The selective extractant was a mixture of dioctylphosphonic acid and trioctylphosphine oxide in a mass ratio of 6:4 to 7:3, dissolved in sulfonated kerosene, with an organic phase concentration of 0.5 mol / L to 0.8 mol / L. 10 mL of the crude cobalt solution sample was taken, and the hydrogen ion concentration was adjusted to different concentration gradients (0.01 mol / L, 0.05 mol / L, 0.1 mol / L, 0.5 mol / L, 1.0 mol / L, 2.0 mol / L, and 5.0 mol / L) using hydrochloric acid or sodium hydroxide solution. Under each hydrogen ion concentration condition, 2 mL of crude cobalt solution and 0.5 mL of selective extractant were placed in the reaction cell of a microcalorimeter. Complexation reactions were tested at a constant temperature of 25 °C, and the heat flow curves of the reaction process were recorded. The heat of reaction for the complexation of cobalt ions with the selective extractant was calculated to be -15 kJ / mol to -22 kJ / mol, for nickel ions -8 kJ / mol to -12 kJ / mol, and for manganese ions -5 kJ / mol to -9 kJ / mol. The absolute difference between the absolute values ​​of the cobalt ion complexation heat and the nickel ion complexation heat was calculated. The difference was 6 kJ / mol at a hydrogen ion concentration of 0.1 mol / L, reached 10 kJ / mol at 0.5 mol / L, was 12 kJ / mol at 1.0 mol / L, and decreased to 9 kJ / mol at 2.0 mol / L. The relationship between the enthalpy change and the hydrogen ion concentration was plotted. By fitting the data points, the curve showed a peak in the range of hydrogen ion concentration from 1.0 mol / L to 1.5 mol / L. The hydrogen ion concentration corresponding to this peak point is the optimal control point, at which the selective extractant has the greatest selectivity difference for cobalt ions and impurity ions.

[0054] The crude cobalt solution was returned entirely to the extraction tank. A 6 mol / L hydrochloric acid solution or a 4 mol / L sodium hydroxide solution was used as the acid-base regulator. The hydrogen ion concentration in the solution was monitored using a pH meter and a hydrogen ion selective electrode. The acid-base regulator was slowly added dropwise using a peristaltic pump at a rate controlled between 5 mL / min and 10 mL / min. Continuous stirring was maintained during the addition to ensure thorough mixing. The addition was stopped when the hydrogen ion concentration reached the control point of 1.0 mol / L to 1.5 mol / L. After stabilizing for 5 minutes, the hydrogen ion concentration was measured again, ensuring the deviation was within ±0.05 mol / L.

[0055] The optimal total dosage of the selective extractant was determined using a batch addition method. Organic phases of the selective extractant were prepared at concentrations ranging from 0.6 mol / L to 0.8 mol / L. 100 mL of the adjusted crude cobalt solution was placed in a separatory funnel, and 10 mL of the selective extractant was added as the first batch. The volume ratio of the organic phase to the aqueous phase was 1:10. Extraction was performed by shaking at a frequency of 180 times / min for 5 min, followed by standing for 8 to 12 min to separate the layers. The upper organic phase was then separated, and the absorbance of the cobalt complex in the organic phase was measured spectrophotometrically at a wavelength of 510 nm. The absorbance of the organic phase after the first extraction was 0.385. Simultaneously, the lower aqueous phase sample was taken, and the concentration of residual cobalt ions in the aqueous phase was determined to be 16.2 g / L using atomic absorption spectrometry. For the second batch, 10 mL of selective extractant was added to the aqueous phase, and the above extraction and layering determination process was repeated. The absorbance of the organic phase was 0.362, the cobalt ion concentration in the aqueous phase was 13.8 g / L, and the absorbance increment was 0.362 - 0.385 = -0.023. After the third batch, the absorbance of the organic phase was 0.341, the cobalt ion concentration in the aqueous phase was 11.5 g / L, and the absorbance increment was -0.021. After the fourth batch, the absorbance of the organic phase was 0.325, the cobalt ion concentration in the aqueous phase was 9.6 g / L, and the absorbance increment was -0.016. After the fifth batch, the absorbance of the organic phase was 0.318, the cobalt ion concentration in the aqueous phase was 8.2 g / L, and the absorbance increment was -0.007. After the sixth batch of addition, the absorbance of the organic phase was 0.315, the cobalt ion concentration in the aqueous phase was 7.5 g / L, and the absorbance increment was -0.003. The absorbance increment threshold was set at -0.005, and the cobalt ion concentration threshold in the aqueous phase was set at 8.0 g / L. When the absolute value of the absorbance increment was less than the increment threshold and the cobalt ion concentration in the aqueous phase was less than the concentration threshold at the time of the sixth batch of addition, the conditions for terminating the addition were met. The total amount of selective extractant added after six batches was 60 mL, which is equivalent to a volume ratio of organic phase to aqueous phase of 0.6:1.

[0056] According to the determined dosage, the selective extractant was added to the extraction reactor containing the crude cobalt solution. The extraction reactor was an extraction tank equipped with a stirrer. The stirring device was turned on, and the stirring speed was set to 350 rpm to 450 rpm. The extraction contact time was 20 min to 30 min. After extraction, stirring was stopped, and the sedimentation time was 30 min to 45 min to ensure complete separation of the two phases. The lower aqueous phase was discharged through the bottom discharge valve, and the upper organic phase, which is the second organic phase, was collected from the top. The second organic phase was back-extracted with a 5 mol / L sulfuric acid solution at a volume ratio of 1:0.4. The contact time was 20 min at a stirring speed of 400 rpm. After sedimentation, the separated aqueous phase was the high-purity cobalt solution with a cobalt ion concentration of 22 g / L to 28 g / L, a cobalt to nickel concentration ratio >100, a cobalt to manganese concentration ratio >250, and a cobalt to copper concentration ratio >600, which meets the raw material requirements for subsequent electrolysis or crystallization processes.

[0057] In one optional embodiment, the concentrations of nickel and manganese ions in the first aqueous phase are detected, and two pH ranges are calculated based on the solubility product constant. A nickel precipitate is obtained through staged precipitation, comprising: Take the first aqueous phase sample, measure the nickel ion concentration and manganese ion concentration, calculate their concentration ratio, and substitute the corresponding solubility product constant into the equilibrium calculation to obtain the corresponding hydroxide ion concentration at which manganese ions are completely precipitated and nickel ions begin to precipitate. Convert the corresponding pH value through the ion product constant to obtain the first numerical range. An alkaline precipitant is added to the first aqueous phase to adjust the pH value to the first value range, and solid-liquid separation is performed to obtain manganese precipitate and first filtrate. The concentration of nickel ions in the first filtrate is measured, and the concentration and the solubility product constant of nickel ions and hydroxide are substituted into the equilibrium calculation to obtain the pH value at which nickel ions are completely precipitated. A second numerical range is determined, and an alkaline precipitant is added to the first filtrate to adjust the pH value to the second numerical range. Solid-liquid separation is then performed to obtain high-purity nickel precipitate.

[0058] The concentrations of nickel and manganese ions in the first aqueous phase were analyzed. Atomic absorption spectrometry was used for quantitative detection of the first aqueous phase sample. 100 mL of the first aqueous phase sample was placed in a clean beaker, diluted appropriately, and then sent to the detection instrument. The concentration of nickel ions was measured to be 8.5 g / L at a wavelength of 232.0 nm, and the concentration of manganese ions was measured to be 2.3 g / L at a wavelength of 279.5 nm. The measured molar concentrations of nickel ions were converted to approximately 0.145 mol / L, and the molar concentrations of manganese ions were converted to approximately 0.042 mol / L. The concentration ratio of the two was approximately 3.45:1.

[0059] Based on the solubility product constant of manganese hydroxide being 1.9 × 10⁻⁶... -13The solubility product constant of nickel hydroxide is 5.5 × 10⁻⁶. -16 Based on the actual measured ion concentrations, equilibrium calculations were performed. For complete precipitation of manganese ions, a residual concentration below 0.001 mol / L was considered complete precipitation. The residual concentration of 0.001 mol / L was then compared with the solubility product constant of 1.9 × 10⁻⁶. -13 Substituting into the equilibrium relationship, the square of the required hydroxide ion concentration should be equal to the solubility product constant divided by the manganese ion concentration, i.e., 1.9 × 10⁻⁶. -10 After taking the root, the hydroxide ion concentration was 1.38 × 10⁻⁶. -5 mol / L, corresponding to a hydrogen ion concentration of 7.25 × 10⁻⁶. -10 mol / L, which translates to a pH value of approximately 9.14.

[0060] The critical condition for the initiation of nickel ion precipitation was determined by comparing the measured nickel ion concentration of 0.145 mol / L with the solubility product constant of 5.5 × 10⁻⁶. -16 Substituting into the equilibrium relationship, the square of the hydroxide ion concentration should be equal to the solubility product constant divided by the nickel ion concentration, i.e., 3.79 × 10⁻⁶. -15 After taking the root, the hydroxide ion concentration was 6.15 × 10⁻⁶. -8 mol / L, corresponding to a hydrogen ion concentration of 1.63 × 10⁻⁶. - 7 The concentration of manganese ions is approximately 6.79, which translates to a pH value of 6.79. Considering both the buffer range and the degree of precipitation in practical operations, the first pH range was determined to be 8.8 to 9.3. This range ensures sufficient precipitation of manganese ions while avoiding excessive co-precipitation of nickel ions.

[0061] The pH value was adjusted by adding an alkaline precipitant in batches to the first aqueous phase. The alkaline precipitant could be sodium hydroxide solution, calcium hydroxide slurry, or sodium carbonate solution. Using 1L of the first aqueous phase as a treatment unit, a 20% sodium hydroxide solution was prepared as the alkaline precipitant and added slowly at a rate of 2mL / min under continuous stirring. During the addition, the pH value was monitored in real time using a pH meter. When the pH value reached 7.5, the addition rate was reduced to 0.5mL / min. The addition was stopped when the pH value rose to 9.0. At this point, the solution was a light brown turbid state. Manganese ions reacted with hydroxide ions to form manganese hydroxide precipitate. The precipitate was allowed to stand for 30 minutes to fully aggregate and settle.

[0062] Solid-liquid separation is performed using a plate and frame filter press or a vacuum filtration device. The suspension containing manganese precipitate is poured into the filtration equipment and separated by pressure filtration at 0.3 MPa. The filter cake is the manganese precipitate, and the filtrate is collected as the first filtrate. The manganese precipitate is brown and muddy with a water content of about 45%. After drying, manganese dioxide or other manganese compound products can be obtained. The first filtrate is a light green transparent liquid with a volume of about 92% of the original first aqueous phase.

[0063] The nickel ion concentration in the first filtrate was determined again. A 50 mL sample of the first filtrate was analyzed, and the nickel ion concentration was found to be 8.2 g / L, which translates to a molar concentration of approximately 0.140 mol / L, indicating minimal nickel ion loss during the fractional precipitation process. This measured concentration of 0.140 mol / L was then compared with the solubility product constant of nickel hydroxide, which is 5.5 × 10⁻⁶ g / L. -16 Substituting into the equilibrium calculation, for nickel ions to be completely precipitated to a residual concentration of 0.0005 mol / L, the square of the hydroxide ion concentration should be equal to 1.1 × 10⁻⁶. -12 After taking the root, the hydroxide ion concentration was 1.05 × 10⁻⁶. -6 mol / L, corresponding to a hydrogen ion concentration of 9.52 × 10⁻⁶. -9 The concentration is mol / L, which translates to approximately pH 8.02. Considering the supersaturation requirements of the precipitation reaction and the margin for actual operation, the second numerical range is determined to be pH 10.5 to 11.5. This range ensures sufficient precipitation of nickel ions and high purity of the precipitate.

[0064] Add alkaline precipitant to the first filtrate to adjust the pH to the second range. Using 500 mL of the first filtrate as a treatment unit, use a 30% sodium hydroxide solution as the precipitant, adding it dropwise at a rate of 1 mL / min while stirring. When the pH reaches 10.0, a pale green flocculent precipitate begins to appear. Continue adding the precipitant until the pH reaches 11.0, at which point nickel ions react with hydroxide ions to form nickel hydroxide precipitate. Maintain this pH and continue stirring for 20 min to allow the precipitation reaction to proceed fully, then allow to settle for 40 min.

[0065] The suspension containing nickel precipitate was subjected to solid-liquid separation using a centrifuge or filter press. Centrifugation at 3000 rpm for 15 min or filter press separation at 0.4 MPa yielded a pale green solid, which was the high-purity nickel precipitate. The filtrate was the second filtrate. After washing to remove residual alkali, the nickel precipitate was dried at 80℃ for 4 h to obtain nickel hydroxide with a nickel content of not less than 60% and a manganese content of less than 0.3%, achieving efficient separation and purification of nickel and manganese.

[0066] This invention provides a high-purity cascade recovery system for ternary materials based on leaching extraction, comprising: The first unit is used to obtain waste ternary materials. By controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material. The second unit is used to leach the processed material in stages, collect the concentration of cobalt ions and nickel ions, and calculate the concentration increment at multiple consecutive time points. When the concentration increment is lower than the rate threshold, the first leaching stage is terminated to obtain a first leaching solution and a first leaching residue containing cobalt and nickel. The first leaching residue is then subjected to a second leaching stage reaction to obtain a second leaching solution containing manganese, which is then precipitated to obtain manganese precipitate. The third unit is used to detect the cobalt ion concentration, nickel ion concentration and hydrogen ion concentration of the first leachate, and determine the extractant ratio. Based on the hydrogen ion concentration and the extraction equilibrium constant, the extractant dosage is calculated in combination with the coordination saturation capacity to extract the first organic phase and the first aqueous phase. The fourth unit is used to perform the first organic reverse extraction to obtain a crude cobalt solution, detect its purity and calculate the ratio of cobalt ion concentration to impurity ion concentration. When the ratio is lower than the threshold, it is returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction distribution ratio difference is calculated to determine the amount of selective extractant to be added for a second extraction to obtain a cobalt solution. The fifth unit is used to detect the concentrations of nickel and manganese ions in the first aqueous phase, calculate the two pH ranges using the solubility product constant, and obtain nickel precipitate through segmented precipitation.

[0067] A third aspect of the present invention provides an electronic device, comprising: processor; Memory used to store processor-executable instructions; The processor is configured to invoke instructions stored in the memory to execute the aforementioned method.

[0068] A fourth aspect of the present invention provides a computer-readable storage medium having stored thereon computer program instructions that, when executed by a processor, implement the aforementioned method.

[0069] This invention can be a method, apparatus, system, and / or computer program product. The computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for performing various aspects of the invention.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for high-purity graded recovery of ternary materials based on leaching extraction, characterized in that, include: Waste ternary materials are obtained, and by controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material. The material to be processed is leached in stages. The concentrations of cobalt ions and nickel ions are collected, and the concentration increments at multiple consecutive time points are calculated. When the concentration increments are lower than the rate threshold, the first leaching stage is terminated, resulting in a first leaching solution and a first leaching residue containing cobalt and nickel. The first leaching residue is then subjected to a second leaching stage reaction to obtain a second leaching solution containing manganese. Manganese precipitate is then obtained from the precipitate. The concentrations of cobalt ions, nickel ions, and hydrogen ions in the first leachate are detected, and the extractant ratio is determined. Based on a comparison of the hydrogen ion concentration and the extraction equilibrium constant, and combined with the coordination saturation capacity, the extractant dosage is calculated. Extraction yields a first organic phase and a first aqueous phase, comprising: The first leachate was sampled, and its cobalt ion concentration, nickel ion concentration, and hydrogen ion concentration were measured. Based on the hydrogen ion concentration, combined with the Nernst equation and introducing a competitive extraction coefficient correction term, a set of mass conservation equations and a set of phase equilibrium equations for cobalt-nickel bicomponent competitive extraction are established. By solving these equations simultaneously, the ratio of the main extractant to the co-extractant is obtained. Substituting the cobalt ion concentration and the nickel ion concentration into the ratio relationship, the mass ratio between the extractant components is obtained. The coordination saturation capacity is coupled with the set comparison parameters to construct a ternary constraint equation that includes the extractant dosage, organic phase volume, and aqueous phase volume. An extraction kinetic rate constant is introduced to establish a differential equation between the extraction completion degree and the extractant concentration gradient. The evolution curve of the extractant concentration over time is obtained by solving the numerical integration method. The extractant concentration corresponding to the inflection point of the extraction curve is taken as the optimal dosage concentration, and the extractant dosage is calculated. After mixing the extractant according to the mass ratio, the extractant is added to the first leachate for extraction reaction. After standing and separating into layers, the first organic phase and the first aqueous phase are obtained. The crude cobalt solution was obtained by the first organic reverse extraction. The purity was tested and the ratio of cobalt ion concentration to impurity ion concentration was calculated. When the ratio was lower than the threshold, it was returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction partition ratio difference was calculated to determine the amount of selective extractant to be added for a second extraction to obtain a cobalt solution. The concentrations of nickel and manganese ions in the first aqueous phase were measured, and the two pH ranges were calculated based on the solubility product constant. Nickel precipitate was obtained by fractional precipitation. The process involves coupling the coordination saturation capacity with a set ratio parameter to construct a ternary constraint equation including the extractant dosage, organic phase volume, and aqueous phase volume. An extraction kinetic rate constant is introduced, and a differential equation is established between the extraction completion degree and the extractant concentration gradient, including: The number of coordination active sites and steric hindrance coefficients in the extractant molecule are determined, and the theoretical coordination capacity of a single extractant molecule is calculated. Extraction equilibrium data under different extractant concentrations were collected. The extractant concentration and the corresponding metal ion extraction amount were substituted into the mass balance equation. The actual coordination saturation capacity was obtained by iterative solution, and the coordination efficiency correction factor was calculated. Based on the initial concentration of the target metal ions in the aqueous phase to be treated and the set target value of extraction completion, the total amount of metal ions that need to be coordinated is calculated. The coordination efficiency correction factor and the actual coordination saturation capacity are substituted into the material balance equation to establish a ternary constraint equation between the amount of extractant added, the volume of the organic phase, and the volume of the aqueous phase. Under different temperatures and stirring rates, the curves of metal ion concentration versus time were calculated. The differential processing was performed to obtain the relationship between the extraction rate and time. Combined with the extractant concentration gradient data, the extraction kinetic rate constant was obtained by fitting. The extraction kinetic rate constant, extractant concentration gradient, and extraction completion degree were used to construct a differential equation.

2. The method according to claim 1, characterized in that, By controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material, including: Based on the initial moisture content and organic component content of the waste ternary material, the drying energy consumption coefficient is calculated, the drying temperature and time are determined, and the waste ternary material is dried to obtain dried material. Based on the thermal decomposition temperature range of the organic binder component in the dried material and the oxidation critical temperature of the metal oxide component, the temperature difference is calculated to determine the pyrolysis temperature gradient and heating rate. During the pyrolysis process, the oxygen concentration in the furnace and the carbon dioxide concentration in the exhaust gas are monitored in real time, and the flow rate and composition of the introduced atmosphere are dynamically adjusted. When the carbon dioxide concentration reaches a maximum value, it is determined that the organic component decomposition is complete, and the oxygen concentration is reduced to the inert protection range to obtain the pyrolyzed material. Based on the magnetic characteristic parameters of the current collector metal in the pyrolysis material, the magnetic field strength and magnetic separation speed of the magnetic separator are determined, and the pyrolysis material is separated by magnetic separation to obtain the current collector metal component and the non-magnetic component. The non-magnetic component is collected as the processed material.

3. The method according to claim 1, characterized in that, The material to be processed is leached in stages. Cobalt ion concentration and nickel ion concentration are collected, and the concentration increments at multiple consecutive time points are calculated. The first leaching stage is terminated when the concentration drops below a rate threshold, resulting in a first leaching solution and a first leaching residue containing cobalt and nickel, comprising: The elemental contents of cobalt, nickel, and manganese in the treated material were detected, and polynomial fitting was performed on the dissolution rate data of cobalt, nickel, and manganese metal oxides at different hydrogen ion concentrations to construct a correlation function between the leaching rate of cobalt, nickel, and manganese and the hydrogen ion concentration. The cobalt-nickel joint leaching rate function and the manganese leaching rate function were obtained, and the difference between them at each hydrogen ion concentration point was calculated. The hydrogen ion concentration corresponding to the largest difference was selected as the target hydrogen ion concentration. The dosage of the leaching agent was determined in combination with the mass of the treated material. The treated material was mixed with the prepared leaching agent and the first leaching stage reaction was carried out. During the reaction in the first leaching stage, leachate samples are collected at fixed intervals, and the concentration values ​​of cobalt ions and nickel ions are detected. The cobalt ion concentration values ​​obtained from multiple consecutive samplings are selected, and the instantaneous leaching rates of cobalt ions and nickel ions are calculated using the three-point difference method. When the instantaneous leaching rates are all lower than the corresponding rate thresholds, the cobalt and nickel leaching is determined to be complete. The reaction in the first leaching stage is then terminated, and solid-liquid separation is performed to obtain the first leaching solution and the first leaching residue containing cobalt and nickel.

4. The method according to claim 1, characterized in that, The crude cobalt solution obtained by the first organic back-extraction is tested for purity and the ratio of cobalt ion concentration to impurity ion concentration is calculated. When the ratio is lower than the threshold, the system is returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction partition ratio difference is calculated to determine the dosage of selective extractant for a second extraction. The cobalt solution is obtained by back-extraction again, including: The first organic phase was subjected to back-extraction reaction. After phase separation, a crude cobalt solution was obtained, and the ratio of cobalt ion concentration to the concentration of each impurity ion was calculated. The heat of complexation reaction of the crude cobalt solution and the selective extractant at different hydrogen ion concentrations was determined by calorimetry. The difference in enthalpy change of complexation reaction between cobalt ions and impurity ions was calculated, and a curve of its change with hydrogen ion concentration was plotted. The hydrogen ion concentration corresponding to the peak of the curve was extracted as the control point. The crude cobalt solution is returned to the extraction system, and an acid-base regulator is added to adjust the hydrogen ion concentration to the control point value. Selective extractant was added in batches, and the mixture was subjected to shaking extraction and allowed to stand for separation. The absorbance of the cobalt complex in the organic phase and the concentration of cobalt ions in the aqueous phase were determined by spectrophotometry. When the increase in absorbance was less than the increment threshold and the concentration of cobalt ions in the aqueous phase was less than the concentration threshold, the total amount of selective extractant added from each batch was accumulated and added to the extraction system to complete the secondary extraction. After standing for separation, the second organic phase was obtained. The second organic phase was then back-extracted to obtain a cobalt solution.

5. The method according to claim 1, characterized in that, The concentrations of nickel and manganese ions in the first aqueous phase were measured, and the two pH ranges were calculated using the solubility product constant. The nickel precipitate was obtained through fractional precipitation, including: Take the first aqueous phase sample, measure the nickel ion concentration and manganese ion concentration, calculate their concentration ratio, and substitute the corresponding solubility product constant into the equilibrium calculation to obtain the corresponding hydroxide ion concentration at which manganese ions are completely precipitated and nickel ions begin to precipitate. Convert the corresponding pH value through the ion product constant to obtain the first numerical range. An alkaline precipitant is added to the first aqueous phase to adjust the pH value to the first value range, and solid-liquid separation is performed to obtain manganese precipitate and first filtrate. The concentration of nickel ions in the first filtrate is measured, and the concentration and the solubility product constant of nickel ions and hydroxide are substituted into the equilibrium calculation to obtain the pH value at which nickel ions are completely precipitated. A second numerical range is determined, and an alkaline precipitant is added to the first filtrate to adjust the pH value to the second numerical range. Solid-liquid separation is then performed to obtain high-purity nickel precipitate.

6. A high-purity cascade recovery system for ternary materials based on leaching extraction, used to implement the method as described in any one of claims 1-5, characterized in that, include: The first unit is used to obtain waste ternary materials. By controlling the temperature and atmosphere, the organic binder components and metal oxide components are separated to obtain the processed material. The second unit is used to leach the processed material in stages, collect the concentration of cobalt ions and nickel ions, and calculate the concentration increment at multiple consecutive time points. When the concentration increment is lower than the rate threshold, the first leaching stage is terminated to obtain a first leaching solution and a first leaching residue containing cobalt and nickel. The first leaching residue is then subjected to a second leaching stage reaction to obtain a second leaching solution containing manganese, which is then precipitated to obtain manganese precipitate. The third unit is used to detect the cobalt ion concentration, nickel ion concentration and hydrogen ion concentration of the first leachate, and determine the extractant ratio. Based on the hydrogen ion concentration and the extraction equilibrium constant, the extractant dosage is calculated in combination with the coordination saturation capacity to extract the first organic phase and the first aqueous phase. The fourth unit is used to perform the first organic reverse extraction to obtain a crude cobalt solution, detect its purity and calculate the ratio of cobalt ion concentration to impurity ion concentration. When the ratio is lower than the threshold, it is returned to the extraction system. After adjusting the hydrogen ion concentration, the extraction distribution ratio difference is calculated to determine the amount of selective extractant to be added for a second extraction to obtain a cobalt solution. The fifth unit is used to detect the concentrations of nickel and manganese ions in the first aqueous phase, calculate the two pH ranges using the solubility product constant, and obtain nickel precipitate through segmented precipitation.

7. An electronic device, characterized in that, include: processor; Memory used to store processor-executable instructions; The processor is configured to invoke instructions stored in the memory to execute the method according to any one of claims 1 to 5.

8. A computer-readable storage medium having computer program instructions stored thereon, characterized in that, When the computer program instructions are executed by the processor, they implement the method described in any one of claims 1 to 5.

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