437results about "Nickel sulfates" patented technology

The invention provides a treatment method of a nickel sulfate solution, and relates to the technical field of non-ferrous metal smelting. The treatment method of the nickel sulfate solution comprises a neutralization procedure, an extraction and oil removal procedure, an electrodeposition procedure and a nickel deposition procedure, in the neutralization procedure, a nickel deposition material generated by anolyte deposition in the nickel deposition procedure serves as a neutralizer to adjust the pH value back, and the solution obtained after neutralization and impurity removal is subjected to extraction, oil removal and electrodeposition to obtain anolyte. And continuously precipitating the anolyte to obtain a nickel precipitation material. The first solid produced by the treatment method of the nickel sulfate solution can be used for pyrogenic production of high matte nickel and electrodeposition procedures, part of impurities in raw materials can be discharged out of a system through the first solid, no dangerous waste residue is produced, and therefore the number of needed filter presses, the number of solid residue filter pressing times and the residue discharging workload are reduced. As calcium powder is not used for neutralization in the neutralization process, the problem of pipeline blockage caused by precipitation of saturated calcium is reduced.

The present invention provides a method for jointly treating laterite nickel ore and nickel-iron alloy and recovering nickel and iron, comprising: (1) slurrying the laterite nickel ore and then performing acid leaching treatment, and obtaining a first leachate after solid-liquid separation; (2) mixing the nickel-iron alloy and the first leachate obtained in step (1) for reaction, and obtaining a second leachate after solid-liquid separation; (3) mixing a phosphorus source, an oxidant, a precipitant and the second leachate obtained in step (2) for reaction, and obtaining an iron phosphate product and a nickel-containing solution after solid-liquid separation; (4) sequentially removing impurities, concentrating and crystallizing the nickel-containing solution obtained in step (3) to obtain battery-grade nickel sulfate. The method utilizes the laterite nickel ore atmospheric pressure leachate, which is high in acid and rich in Fe 3+ The nickel-iron alloy is treated by using the nickel-iron to neutralize the residual acid in the leaching solution and to utilize the residual acid and Fe in the leaching solution. 3+ The strong oxidizing property promotes the dissolution of nickel-iron, achieving efficient recovery of nickel and iron, and ultimately obtaining iron phosphate and battery-grade nickel sulfate.

The invention discloses a method for recovering and separating nickel, cobalt and manganese from waste ternary lithium ion battery material lithium extraction slag, which comprises the following steps: pulping waste ternary battery material lithium extraction slag, leaching, introducing compressed air as an oxidant, and carrying out solid-liquid separation after leaching to obtain a leachate and leaching slag; sequentially performing copper removal, iron removal, aluminum removal and fluorine removal on the leachate to finally obtain fluorine-removed liquid; carrying out refined filtration on the fluorine-removed liquid to obtain a refined-filtered liquid; adjusting the pH value of the finely filtered liquid, and extracting impurities by using nickel soap P204 to obtain a rich organic phase and raffinate 1; extracting manganese from the raffinate 1 by using nickel soap P204 to obtain a manganese-rich organic phase and raffinate 2; extracting cobalt from the raffinate 2 by using nickel soap P507 to obtain a cobalt-rich organic phase and raffinate 3; and carrying out evaporative crystallization on the raffinate 3 to obtain nickel sulfate. The whole process has the advantages of short flow, high metal recovery rate, high product quality and low sodium-containing wastewater treatment capacity, and nickel, cobalt, manganese and lithium elements in the waste ternary lithium ion battery material are efficiently recycled by combining a front-end lithium extraction and recovery process, so that resource circulation is realized.

The disclosure discloses a method for preparing battery-grade nickel-cobalt-manganese sulfate crystals from low nickel matte, which includes the following steps: S1, sequentially performing high-pressure leaching, iron-aluminum removal and nickel-cobalt-manganese precipitation treatment on laterite nickel ore to obtain an underflow containing nickel-cobalt-manganese hydroxide, wherein the pH value of the underflow is 7-8; S2, performing oxygen-pressure leaching on the low nickel matte using sulfuric acid and oxygen to obtain a leached slurry containing residual acid, adding the underflow into the leached slurry to obtain a mixed slurry, and adjusting the pH value of the mixed slurry to be 3-5 using the underflow; and S3, performing filter pressing on the mixed slurry to obtain filtrate and tailings, and performing nickel-cobalt-manganese co-extraction, concentration and crystallization on the filtrate to obtain the nickel-cobalt-manganese sulfate crystals. The method has the advantages of high utilization rate of nickel, cobalt and manganese, few impurities, reduced reagent consumption and technological processes, and high transportation efficiency.

A treatment process for crystallizing a metal sulfate involving pre-treating a feedstock comprising calcium, magnesium, and / or lithium impurities, the pre-treating involving pre-leaching the feedstock in the presence of a lixiviant, selectively extracting a first portion of any of the impurities from the feedstock, and forming a leached solution comprising an uncrystallized metal sulfate and any remaining impurities; and / or refining the leached solution and removing a second portion of any of the remaining impurities; and crystallizing the uncrystallized metal sulfate from the leached solution to form a crystallized metal sulfate. So processed, the crystallized metal sulfate may be battery-grade or electroplating-grade.

The present invention provides a nickel smelting method which includes: (A-i) a reduction heat treatment process of heat-treating a first raw material containing nickel and lithium; (B) a first leaching process of leaching a heat treatment product generated by the reduction heat treatment process; (A-ii) a roasting process of heat-treating a second raw material containing nickel and sulfur; (C) a second leaching process of leaching a first leaching residue generated by the first leaching process and a calcine generated by the roasting process; (D) a neutralization process of neutralizing a second leached solution generated by the second leaching process; (E) a purification process of removing impurities contained in a neutralized solution generated by the neutralization process; and (F) a precipitation process of performing a precipitation method for recovering nickel from a purified solution generated by the purification process, wherein nickel hydroxide is recovered by the precipitation process.

The invention belongs to the technical field of waste battery recovery and regeneration, and particularly relates to a method for recovering valuable metal from a waste lithium battery positive electrode material. The method comprises the following steps: carrying out sulfuration roasting on waste positive electrode powder, selectively extracting lithium in a water leaching manner, and precipitating lithium to obtain lithium carbonate; separating and purifying the nickel, the cobalt and the manganese through microwave acid leaching, precipitation impurity removal and step-by-step extraction to obtain extract liquor of the nickel, the cobalt and the manganese, and performing reverse extraction on the extract liquor to obtain battery-grade cobalt sulfate, battery-grade nickel sulfate and battery-grade manganese sulfate. According to the method, lithium is extracted firstly, the influence of the lithium element on subsequent nickel-cobalt-manganese extraction is reduced, meanwhile, the recovery rate of lithium is increased through the water leaching method, and the recovery cost is reduced. According to the method, precipitation and impurity removal are performed before nickel-cobalt-manganese extraction, so that the content of impurities in a sulfate solution is reduced, and the recovery rate of nickel, cobalt and manganese is greatly improved.

The invention relates to a method for recycling battery-grade nickel sulfate from nickel-containing industrial waste, and belongs to the technical field of nonferrous metallurgy. The method comprises the steps that the nickel-containing industrial waste is subjected to water leaching treatment, and nickel-containing leachate is obtained; carrying out gradient pH regulation and control on the nickel-containing leaching solution by adopting calcium carbonate to obtain a purified solution; carrying out first countercurrent extraction on the purified liquid by adopting an organic phase I with the D2EHPA concentration of 0.1-0.3 mol / L; carrying out second counter-current extraction on the raffinate I obtained in the step (3) by adopting an organic phase II with the CYANEX 272 concentration of 0.05-0.2 mol / L; the raffinate II obtained in the step (4) is subjected to adsorption and oil removal through activated carbon and then is subjected to evaporative crystallization, and nickel sulfate crystals and crystallization mother liquor are obtained. The method is high in nickel recovery rate, the purity of nickel sulfate is larger than or equal to 99.9%, and the sodium content is low.

The utility model relates to the field of hydrometallurgy, in particular to a nickel sulfate solution deoiling device. Comprising a standing tank connected with a production process outlet end, one end of an oil removal device is connected with the standing tank, the other end of the oil removal device is connected with a resin adsorption column, the resin adsorption column is connected with a regeneration tank, and the regeneration tank is connected with a solution storage tank. According to the oil removal device arranged in the device, oil can be treated step by step according to different existing forms and physical properties of oil in nickel sulfate through internal fiber cotton filtration, resin adsorption and filter screen filtration, and compared with the prior art, the oil removal effect is better; the device is provided with the oil-water separator and the bag filter, so that the oil removal effect can be further improved, and impurities in the nickel sulfate solution can be separated.

The invention discloses a method for preparing battery-grade nickel sulfate through collaborative purification of crude nickel sulfate and crude nickel carbonate. According to the method, crude nickel sulfate is dissolved firstly, then crude nickel carbonate is utilized for batch synergistic neutralization, and the alkalinity of the nickel carbonate is effectively utilized to reduce extra acid and alkali consumption. And then through multi-stage fine purification, including Fe oxidation and preliminary precipitation, Cr (VI) reduction and high-pH precipitation, main impurities such as iron, chromium, aluminum and the like are efficiently removed. And after the mother liquor is adsorbed by activated carbon and trace impurities are removed by strong-acid cation exchange resin, vacuum evaporation and concentration are carried out, and seed crystals are introduced for cooling crystallization, so that pure NiSO4. 6H2O crystals are obtained. The whole technological process pays attention to resource recycling, washing water recycling and nickel recycling of nickel-containing filter residues, waste gas and waste liquid are treated, and clean production is achieved. The nickel sulfate product prepared by the method is high in purity, meets the battery grade standard, and has good economic benefits and environmental benefits.

The invention discloses a clean production process for cyclic utilization of nickel-containing waste, which comprises the following steps: placing nitrogen trifluoride electrolysis nickel-containing waste residue in an electrothermal furnace, sublimating or decomposing ammonium bifluoride in the nickel-containing waste residue, condensing, liquefying and crystallizing through a condensing system to re-synthesize ammonium bifluoride for sale or reuse; the main components of the material a heated and volatilized by the electrothermal furnace are nickel fluoride, ferric fluoride and copper fluoride; adding the material a into an alkaline material solution for conversion leaching to obtain nickel hydroxide, ferric hydroxide and copper hydroxide, and converting a sodium hydroxide or potassium hydroxide solution into a sodium fluoride or potassium fluoride solution; adding an acid-carrying anolyte of a nickel electrolysis system into the obtained nickel hydroxide, ferric hydroxide and copper hydroxide slag, dissolving nickel hydroxide, ferric hydroxide and copper hydroxide into an electrolyte by using acid in the anolyte, removing metal impurities, and filtering to obtain a pure nickel electrolysis pre-solution; and electrolytic nickel with the nickel content larger than 99.96% of Ni is produced through insoluble anode electrolysis.

The present disclosure provides a method of recovering a spent battery cathode material comprising lithium and at least one of nickel, cobalt and / or manganese, the method comprising: heating the spent battery cathode material in a reducing atmosphere to form a heat-treated spent battery cathode material comprising LiF and one or more of LijO, LiOH and LijCOs; washing the heat treated waste battery cathode material in an aqueous solvent to extract lithium-containing species and fluorine-containing species wherein the aqueous solvent is free of alkaline earth metal hydroxides or other species intended to reduce or prevent soluble fluorine species from remaining dissolved in the aqueous solvent; separating an aqueous solvent comprising lithium and fluorine species from the heat treated waste battery material; after separating an aqueous solvent comprising lithium and fluorine species from the heat-treated waste battery material, treating the aqueous solvent to separate lithium species from fluorine species; recycling a lithium substance in the form of lithium hydroxide or lithium carbonate; forming an acidic aqueous recovery feed comprising one or more of nickel, cobalt and / or manganese by leaching the heat treated waste battery cathode material with a mineral acid after the step of separating the aqueous solvent from the heat treated waste battery material; and recovering one or more of nickel, cobalt and / or manganese from the acidic aqueous recovery feed by a further process step selected from one or more of solvent extraction, solid phase extraction, electrochemical extraction and precipitation processes.

The invention relates to the field of hydrometallurgy, in particular to a method for preparing nickel sulfate from nickel raw material leachate. The trend of the washing liquid in the traditional process is changed in the technological process, so that the amount of the washing liquid entering the nickel sulfate solution is reduced, the concentration of nickel ions in the nickel sulfate solution before evaporation is improved, and the unit cost of evaporative crystallization of nickel sulfate is reduced. P507 cobalt extraction washing liquid enters a P204 impurity extraction and soap conversion section, P507 magnesium extraction washing liquid enters a P507 cobalt extraction and soap conversion section and / or the P204 impurity extraction and soap conversion section, Cy272 magnesium extraction washing liquid enters a P507 magnesium extraction and soap conversion section, the P507 cobalt extraction and soap conversion section and / or the P204 impurity extraction and soap conversion section, and the washing liquid is transferred to the previous procedure and enters the soap conversion section instead of entering an extraction system; washing liquid is discharged out of the system in the form of sodium sulfate wastewater, so that the water phase amount of the system is reduced, and the nickel ion concentration in the nickel sulfate solution is improved.

The utility model discloses a nickel sulfate purification device. The nickel sulfate purification device comprises a purification tank, the top cover is arranged at the top of the purification tank; the stirring assembly is arranged in the top cover; the stirring assembly comprises a motor, a rotating rod and a stirring frame; the top of the top cover is fixedly connected with a motor; an output shaft of the motor is fixedly connected with a rotating rod through a coupling; the outer wall of the rotating rod is fixedly connected with a stirring frame; the filler assembly is arranged at the top of the top cover; the packing assembly comprises a fixing groove, a fixing pipe, a nozzle, a threaded sleeve, a self-locking screw, a piston and an adjusting disc. According to the nickel sulfate purification device, the motor is mounted on the top cover, so that the motor can drive the rotating rod to rotate, the rotating rod can drive the stirring frames on the two sides to rotate, the multiple stirring frames can effectively and uniformly mix materials in the purification tank, the mixing efficiency of various materials can be improved, and the practicability of the nickel sulfate purification device is improved. The practicability of the purification device is improved.

The invention discloses a recycling method of NF3 residual electrolysis liquid, and relates to the technical field of residual electrolysis liquid recycling treatment. The method comprises the following steps: step 1, removing Fe ions in the electrolytic residual liquid: firstly, adding hydrogen peroxide or oxygen into the electrolytic residual liquid for reaction, oxidizing ferrous ions into ferric ions, then adding ammonia water and sodium hydroxide or ammonium bicarbonate and sodium hydroxide into the solution for reaction, precipitating ferric ions in the form of ferric hydroxide; 2, hydrofluoric acid is added into the electrolyte solution obtained after iron removal to adjust the pH of filtrate to 3-12, the filtrate enters an extraction system, the nickel element in ammonium hydrogen fluoride is extracted out, and ammonium hydrogen fluoride is purified; and step 3, the nickel element separated from the electrolyte enters a second section to be extracted and synthesized into a nickel sulfate product.

The invention discloses an efficient and energy-saving purification method for a copper electrolyte. The purification method comprises the following steps: performing MVR (Mechanical Vapor Recompression) concentration; cooling and crystallizing; filtering and separating; electrodeposition copper and impurity removal by a circulation method; freezing and crystallizing; performing centrifugal separation; according to the method, in the MVR concentration process, a high-energy-efficiency steam compressor is used for compressing secondary steam generated by evaporation of the copper electrolyte, the enthalpy of the secondary steam is improved, and the secondary steam with improved heat energy is pumped into a plate heat exchanger to exchange heat with the copper electrolyte, so that the existing heat energy of the secondary steam is recycled; therefore, the consumption of external steam can be reduced to realize evaporation and concentration of the copper electrolyte to produce crude copper sulfate; in the circulation method electrodeposition copper removal and impurity removal process, the crystallization mother liquor is supplemented into the impurity removal circulation liquid, so that copper ions can be kept in an efficient impurity removal concentration range, and the removal efficiency of impurities such as arsenic is improved; a refrigerator is adopted to cool the electrolyte after electrodeposition copper removal and impurity removal, and then a centrifugal machine is adopted to realize solid-liquid separation of nickel sulfate crystals.

The invention discloses a method for deeply removing arsenic from a nickel sulfate solution, which comprises the following steps: adjusting the pH value by using nickel hydroxide to form colloid to preliminarily remove arsenic, oxidizing by using sodium sulfate, and adding polyferric sulfate to form ferric hydroxide colloid to deeply adsorb and remove arsenic, and is simple in process, convenient to implement in the production process, capable of greatly reducing the cost and reducing the environmental pollution, and suitable for industrial production. The method comprises the following steps: adjusting the pH value of a low-pH leaching solution / anolyte / crude nickel sulfate dissolving solution to 4.0 or more by using nickel hydroxide, carrying out filter pressing to remove slag, adding arsenic ions in a sodium persulfate oxidation solution, reacting for 30 minutes, adding polyferric sulfate, reacting for 30 minutes, and carrying out filter pressing to obtain a nickel sulfate solution which is almost free of arsenic, and the method is efficient, safe and environment-friendly.

A waste battery processing method includes a discharging process of discharging a waste battery, a dismantling process of dismantling the discharged waste battery into battery cell units, a shredding process of shredding the dismantled waste battery, a roasting process of roasting the shredded waste battery, a pulverizing process of pulverizing the fired waste battery, and a hydrometallurgical process of extracting and recovering metals from the pulverized waste battery.

The invention discloses an extraction purification deep impurity removal method for a nickel sulfate solution, and belongs to the technical field of nickel sulfate solution purification, and the extraction purification deep impurity removal method comprises the following steps: carrying out saponification treatment on a P204 extraction agent by adopting a sodium hydroxide solution to obtain a saponified organic phase P204, mixing the saponified organic phase P204 with a nickel sulfate water phase, stirring and standing to obtain a nickel sulfate solution; the method comprises the following steps: separating an organic phase from a water phase, mixing the organic phase with sulfuric acid, stirring, standing, separating out a nickel sulfate solution, concentrating the nickel sulfate, and recrystallizing to obtain the high-purity nickel sulfate with the purity of 99.4-99.9%. According to the method, the battery-grade nickel sulfate product with the purity as high as 99.9% can be obtained, the requirement of HG / T2824-2009 first-grade products is met, and the method is particularly suitable for purification of crude nickel sulfate generated in the copper ore smelting process and preparation of the battery-grade nickel sulfate.

The invention provides a doubling treatment method of battery black powder and nickel cobalt hydroxide. The doubling treatment method comprises the following steps: carrying out reduction roasting and water immersion treatment on the battery black powder to obtain a first lithium-containing liquid and a solid product; carrying out acid leaching on the solid product to obtain a leaching solution; after removing impurities from the leachate, extracting the leachate with a first saponification extraction agent to obtain first raffinate and a first extraction organic phase; carrying out soap conversion reaction on the first raffinate and a second saponification extraction agent to obtain a second extracted and soap-converted organic phase and a second lithium-containing liquid; carrying out acid leaching and impurity removal on nickel cobalt hydroxide, and carrying out extraction reaction on the solution and the second extraction soap-converted organic phase to obtain a second extraction organic phase and a second raffinate; the second raffinate is subjected to Co extraction, Mg extraction and evaporative crystallization, and nickel sulfate is obtained; and the organic phase obtained after Co extraction is subjected to back extraction and evaporative crystallization, and cobalt sulfate is obtained. Compared with a traditional doubling treatment technology, the doubling treatment method avoids the problem of impurity pollution caused by doubling treatment of traditional battery black powder and nickel cobalt hydroxide raw materials.

The invention relates to a method for preparing a nickel sulfate solution from a high-nickel, low-copper, high-iron and high-sulfur material. The method comprises the following steps: a normal-pressure slurrying and proportioning stage; a first normal pressure leaching stage; a second-stage normal-pressure leaching stage; a first-stage pressure leaching stage and a second-stage pressure leaching stage. According to the method, by matching the high-copper material, adding proper sulfuric acid and oxygen and controlling the kettle temperature, the kettle pressure and the pH value, the leaching rate of nickel is increased, a relatively pure nickel sulfate solution is obtained, the open circuit problem of high iron and high sulfur in a system is solved, generation of hydrogen sulfide gas is completely eradicated, and meanwhile, two-stage pressure leaching residues can be conveyed to a pyrogenic process system to be recycled.

The invention belongs to the technical field of waste battery recovery, and particularly relates to a short-process method for recovering battery-grade lithium carbonate and valuable metals from waste ternary lithium battery black powder. According to the method, a lithium closed-loop technical system of blank roasting, cyclic leaching, synergistic impurity removal, lithium phosphate aluminum removal, directional extraction and split-flow extraction of lithium, nickel and magnesium and seed crystal induction parallel flow lithium precipitation is constructed, a roasting aid, a reducing agent and an aluminum removal agent do not need to be added in the whole process, and the redundant processes of traditional lithium carbonate purification such as carbonization, resin purification and pyrolysis are omitted; the lithium liquid concentration cost is saved, no hazardous waste exists, green and clean production is achieved, and the quality of battery-grade products is guaranteed through collaborative impurity removal and directional extraction.

The invention discloses a method for preparing battery-grade iron phosphate and battery-grade nickel sulfate from a nickel-iron alloy, and relates to the technical field of lithium ion battery materials. The invention provides a method for preparing battery-grade iron phosphate and battery-grade nickel sulfate by using a nickel-iron alloy, which comprises the following steps of: further removing impurities from a nickel-iron mother solution generated in the production of the battery-grade iron phosphate to obtain the battery-grade nickel sulfate. The iron-containing slag generated in the midway can be returned to the front end to be reused, the leaching efficiency of the nickel-iron alloy is high, and the consumption cost of auxiliary materials is low.

The invention relates to a method for recovering nickel and cobalt from a mixture of compounds of these metals from the recycling of spent lithium-ion batteries, comprising the following steps: a) digestion of a mixture of nickel and cobalt compounds in a solution containing hydrochloric acid having a concentration of more than 25 mass %, in case the mixture of nickel and cobalt compounds is solid; or bringing the mixture of nickel and cobalt compounds to a hydrochloric acid concentration of more than 25 mass %, in case the mixture of nickel and cobalt compounds is a solution; b) activation of ion-exchange resin in a column using hydrochloric acid; c) passing the solution from step a) through the column filled with the ion-exchange resin activated in step b); d) washing the column with hydrochloric acid having a concentration of more than 25 mass % in order to wash out the remaining solution containing nickel ions; e) washing the column with hydrochloric acid having a concentration of less than 10 mass % in order to wash out cobalt ions; f) extraction distillation of the nickel ion solution obtained in step d) in hydrochloric acid using sulfuric(VI) acid; phase separation in a spent liquid; recycling of a filtrate to distillation; dissolution of nickel sulfate(VI) and electrolysis in order to recover metallic nickel; g) extraction distillation of the cobalt ion solution obtained in step e) in hydrochloric acid using sulfuric(VI) acid; phase separation in a spent liquid; recycling of a filtrate to distillation; dissolution of cobalt sulfate(VI) and electrolysis in order to recover metallic cobalt; h) extraction distillation of the solution of diluted hydrochloric acid with nickel and cobalt ions obtained after the activation of the ion-exchange resin in step b), using sulfuric(VI) acid; phase separation in a spent liquid; recycling of a filtrate to distillation; recycling of a mixture of the formed cobalt sulfate(VI) and nickel sulfate(VI) to digestion in step a); i) rectification of diluted hydrochloric acid having a concentration below the azeotropic concentration (approx. 20.2 mass % at atmospheric pressure) formed in extraction distillation processes in steps f)-h) in order to concentrate hydrochloric acid and recover and recycle of water; recycling of concentrated hydrochloric acid to extraction distillation in steps f)-h).

The method for preparing nickel sulfate according to an exemplary embodiment may prepare a nickel-containing raw material. Nickel may be selectively leached from a nickel-containing feedstock using an oxidant to produce a first leachate. Residual metals may be separated from the first leachate to produce a second leachate. Nickel sulfate may then be obtained from the second leachate. Therefore, a separate nickel extraction step can be omitted, thereby reducing unnecessary by-products.

The invention provides a new process for comprehensively recovering valuable metals in ternary positive electrode material powder, which comprises the steps of positive electrode material powder dissolution, metal salt separation, extraction and reverse extraction, lithium salt treatment and the like, acid obtained by electrolysis can be recycled, and a lithium salt solution can be further used for preparing a lithium carbonate product. The process has the remarkable advantages that resource recovery is comprehensive and efficient, the valuable metal recovery rate is high, and the metal separation precision is high; the process is environment-friendly and low in cost, auxiliary materials are recycled, the cost is reduced, and environmental pollution is reduced; the product is excellent in quality, low in impurity content and stable in performance, can meet high-end market requirements, and improves the market competitiveness and the added value. The process has outstanding advantages in the aspects of resource recovery, environmental protection cost, product quality and the like, and has wide application prospects and market values.

The utility model belongs to the technical field of industrial crystallization, and discloses a nickel sulfate continuous crystallization system. Comprising a stock solution storage tank, a pretreatment unit, a concentration unit and a crystallization unit, wherein the pretreatment unit comprises an iron remover, a filter and a preheating assembly which are sequentially communicated with a stock solution storage tank; the concentration unit comprises a forced circulation evaporator and a crystallization separator, and the crystallization unit comprises a cooling crystallizer, a cooling circulation pump, a hot crystal eliminator, a condenser, a condensed water tank, a vacuum pump, a thickener and a centrifugal machine. The nickel sulfate continuous crystallization system disclosed by the utility model is convenient to operate, high in continuous cooling crystallization efficiency and suitable for crystallization of nickel sulfate with different particle size requirements.

The invention relates to the technical field of positive electrode precursors, in particular to a method for preparing a sulfate solution for a precursor by using a cobalt nickel hydroxide intermediate product and application of the sulfate solution. Performing acid leaching on the intermediate product, and then adding a flocculating agent to obtain a cobalt-nickel-manganese mixed solution and manganese slag; extracting the cobalt-nickel-manganese mixed solution and P507-C272, and reversely extracting a loaded organic phase to obtain a crude manganese sulfate solution; performing P204 impurity removal on the raffinate, recovering cobalt by using P507 to obtain a cobalt sulfate solution, and performing C272 nickel-magnesium separation to obtain a nickel sulfate solution; manganese slag is subjected to reduction leaching to obtain reduction leaching liquid, and then the reduction leaching liquid is mixed with a sodium carbonate solution to remove iron to obtain iron-removed liquid; mixing the iron-removed solution with the crude manganese sulfate solution, and removing calcium and magnesium to obtain a calcium-magnesium-removed solution; mixing the calcium and magnesium removed solution with an aluminum source to remove fluorine to obtain a fluorine removed solution; and mixing the fluorine-removed solution with sulfide to remove copper and zinc, adding alkali liquor to obtain a heavy-removed solution, and treating the heavy-removed solution with modified resin to obtain a refined manganese sulfate solution. The method is high in manganese recovery rate and low in treatment cost.

The disclosure discloses a method for preparing a battery-grade nickel-cobalt-manganese sulfate solution from low nickel matte. The method includes the following steps: grinding low nickel matte, then adding the ground low nickel matte to concentrated sulfuric acid, and carrying out atmospheric pressure leaching to obtain a first slag phase and a first liquid phase; carrying out evaporation concentration-cooling crystallization on the first liquid phase to obtain ferrous sulfate crystals; adding concentrated sulfuric acid to the first slag phase, and carrying out oxygen pressure leaching to obtain a second slag phase and a second liquid phase; adjusting pH of the second liquid phase to 3-4 to generate a precipitate, and removing the precipitate by filtration to obtain a filtrate; carrying out adsorption treatment on the filtrate by adopting chelating resin; washing the adsorbed chelating resin with a first sulfuric acid solution to obtain a washing solution containing Mg and Mn, and then washing the chelating resin with a second sulfuric acid solution to obtain a nickel-cobalt sulfate solution; and mixing the nickel-cobalt sulfate solution with the washing solution containing Mg and Mn to obtain the nickel-cobalt-manganese sulfate solution. According to the method of the disclosure, the battery-grade nickel-cobalt sulfate solution is prepared from the low nickel matte as a raw material, so that the recovery rate of nickel and cobalt is increased, and the acid consumption is reduced.

The present invention provides a process for preparing a high-purity nickel sulphate solution, comprising the steps of: i. providing an aqueous feed solution comprising nickel. cobalt, calcium and magnesium: ii. extracting cobalt, calcium, and partly magnesium from said aqueous feed solution using a first solvent comprising a first alkylphosphorus-based acidic extractant, thereby obtaining an aqueous raffinate comprising nickel and magnesium: iii. extracting magnesium from said aqueous raffinate solution comprising nickel and magnesium using a second solvent comprising a second alkylphosphorus-based acidic extractant, thereby obtaining a high-purity aqueous nickel sulphate solution comprising nickel and magnesium: iv. stripping the first loaded solvent comprising cobalt, calcium and magnesium with an aqueous solution comprising a mineral acid.