Method for recovering manganese in manganese-containing waste lithium ion battery

Abstract

The invention provides a method for recovering manganese from a manganese-containing waste lithium ion battery. The method comprises the following steps: obtaining a copper-manganese solution from the manganese-containing waste lithium ion battery; adding a copper removal agent into the copper-manganese liquid, and filtering after reaction to obtain copper-removed liquid; adding pure water into a reaction kettle, heating, simultaneously adding the copper-removed solution and an alkaline precipitant aqueous solution, reacting, and filtering to obtain a crude manganese hydroxide filter cake; adding water into the coarse manganese hydroxide filter cake for size mixing, adding a complex EDTA for complexing, and filtering to obtain a manganese hydroxide filter cake; adding water into the manganese hydroxide filter cake for size mixing, adding an oxidizing agent, stirring for reaction, and filtering to obtain a manganous-manganic oxide filter cake; and washing and drying the manganous-manganic oxide filter cake to obtain the battery grade manganous-manganic oxide. The method for recovering manganese in the manganese-containing waste lithium ion battery provided by the invention is convenient to operate, short in process, low in cost, small in environmental pollution and high in recovery rate.

Description

Technical Field

[0001] The invention relates to the technical field of waste lithium battery recycling, and in particular to a method for recycling manganese in manganese-containing waste lithium ion batteries. Background Art

[0002] As one of the important power sources for new energy vehicles, the production scale of lithium-ion batteries is constantly expanding. Since the life of power lithium-ion batteries is generally 3 to 5 years, a large number of waste lithium-ion batteries will inevitably be generated. These lithium-ion batteries contain valuable resources such as nickel, cobalt, manganese, iron, aluminum, copper and lithium. If they cannot be effectively recycled, they will not only pollute the environment, but also lead to waste of resources and economic losses. In addition, it will also cause the metal resources for manufacturing lithium-ion batteries, especially the metal supply and demand gap of scarce mineral resources such as lithium and cobalt, to widen. Therefore, the development of recycling and reuse technology for waste lithium-ion batteries will help prevent and control waste battery pollution and alleviate the shortage of raw materials related to lithium batteries.

[0003] Manganese-containing waste lithium-ion batteries contain 10%-15% manganese. At present, the process for recovering manganese from waste lithium-ion batteries mainly adopts wet process. The characteristics of this process are flexible operation, easy control of production scale, and mature and stable process conditions. This process is to discharge, disassemble, crush and physically sort the waste lithium-ion batteries. Then, the obtained positive electrode active material is further subjected to acid leaching, wet leaching and extraction technology to recover the manganese resources in the waste lithium-ion batteries, and finally the lithium metal resources in the waste lithium-ion batteries are extracted by carbonate precipitation.

[0004] Among them, P2O4 extraction in the above process will produce copper-manganese liquid. Since the copper-manganese liquid is highly acidic and has a complex composition, containing multiple metal ions such as copper, calcium, manganese, and cobalt, the copper-manganese liquid has a very high recovery value.

[0005] At present, the copper-manganese solution recovery process usually involves first adjusting the pH value to extract copper metal by manganese powder replacement or extraction, then removing calcium by adding fluoride, and finally extracting with P507 to obtain a high-purity manganese sulfate solution. The entire process is long, technically complex, and costly. In addition, fluoride ions are introduced during the calcium removal stage, which are difficult to remove later and are likely to have an impact on the environment.

[0006] Therefore, there is an urgent need to develop a method for recycling manganese in manganese-containing waste lithium-ion batteries that is easy to operate, has a short process, low cost, low environmental pollution and high recovery rate. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a method for recovering manganese from manganese-containing waste lithium-ion batteries, which has the advantages of convenient operation, short process, low cost, small environmental pollution and high recovery rate.

[0008] In order to solve the above technical problems, the present invention provides a method for recovering manganese from manganese-containing waste lithium-ion batteries, comprising the following steps:

[0009] Obtaining copper-manganese liquid from manganese-containing waste lithium-ion batteries;

[0010] Adding a copper removal agent to the copper-manganese solution, filtering after the reaction to obtain a copper-removed solution;

[0011] After adding pure water to the reaction kettle and heating it to 50-90° C., adding the copper removal solution and the alkaline precipitant aqueous solution at the same time, controlling the pH value of the reaction system to be 4.5-8.0, stirring the reaction, and filtering to obtain a crude manganese hydroxide filter cake;

[0012] Add water to the crude manganese hydroxide filter cake to prepare the slurry, then add the complex EDTA for complexation, and then filter to obtain the manganese hydroxide filter cake;

[0013] Add water to the manganese hydroxide filter cake to prepare the slurry, add an oxidant, stir the reaction, and then filter to obtain the manganese tetraoxide filter cake;

[0014] The manganese tetraoxide filter cake is washed and dried to obtain battery-grade manganese tetraoxide.

[0015] The present invention provides another method for recovering manganese from waste lithium-ion batteries containing manganese, comprising the following steps:

[0016] Obtaining copper-manganese liquid from manganese-containing waste lithium-ion batteries;

[0017] Adding a copper removal agent to the copper-manganese solution, filtering after the reaction to obtain a copper-removed solution;

[0018] After adding pure water to the reaction kettle and heating it to 50-90° C., adding the copper removal solution and the alkaline precipitant aqueous solution at the same time, controlling the pH value of the reaction system to be 4.5-8.0, stirring the reaction, and filtering to obtain a crude manganese hydroxide filter cake;

[0019] Add water to the crude manganese hydroxide filter cake to prepare a slurry, add an oxidant, stir the reaction, and then filter to obtain a filter cake;

[0020] Add water to the filter cake to prepare the slurry, then add the complex EDTA for complexation, and then filter to obtain the manganese tetraoxide filter cake;

[0021] The manganese tetraoxide filter cake is washed and dried to obtain battery-grade manganese tetraoxide.

[0022] The present invention provides a method for recovering manganese from waste lithium-ion batteries containing manganese, comprising the following steps:

[0023] Obtaining copper-manganese liquid from manganese-containing waste lithium-ion batteries;

[0024] Adding a copper removal agent to the copper-manganese solution, filtering after the reaction to obtain a copper-removed solution;

[0025] After adding pure water to the reaction kettle and heating it to 50-90°C, adding the copper removal solution and alkaline precipitant aqueous solution at the same time, and then adding an oxidant, controlling the pH value of the reaction system to 4.5-9.5, stirring the reaction, and filtering to obtain a filter cake;

[0026] Add water to the filter cake to prepare the slurry, then add the complex EDTA for complexation, and then filter to obtain the manganese tetraoxide filter cake;

[0027] The manganese tetraoxide filter cake is washed and dried to obtain battery-grade manganese tetraoxide.

[0028] Furthermore, the copper-manganese solution is obtained by the following steps:

[0029] Reduction calcination: The positive electrode black powder separated from the manganese-containing waste lithium-ion battery is calcined at high temperature to obtain a calcined product;

[0030] Water leaching: leaching the roasted product in water to obtain manganese-containing water leaching residue and lithium-rich solution;

[0031] Leaching: leaching the manganese-containing water leaching residue to obtain a manganese-containing leaching solution;

[0032] Extraction: Use an extractant to extract, separate and remove impurities from the manganese-containing leaching solution to obtain copper-manganese solution.

[0033] Furthermore, the extraction is to use P2O4 as an extractant to extract the manganese-containing leaching solution to obtain a raffinate and a loaded organic phase, and the loaded organic phase is back-extracted using a 160-200g / L sulfuric acid solution to obtain a copper-manganese solution.

[0034] Furthermore, the copper removal agent is one or both of manganese powder and iron powder, the amount of the copper removal agent added is 1.1 to 1.3 times the theoretical value of the reaction between the copper removal agent and the copper-manganese solution, the reaction temperature between the copper removal agent and the copper-manganese solution is 50 to 70° C., and the reaction time is 2 to 4 hours;

[0035] The alkaline precipitant in the alkaline precipitant aqueous solution is one or both of sodium hydroxide and ammonia water; the concentration of the alkaline precipitant aqueous solution is 1-10 mol / L.

[0036] Furthermore, the copper-removed liquid is added to the reactor under stirring conditions, and the addition time of the copper-removed liquid is 6 to 20 hours. After the addition is completed, the pH value and temperature are kept unchanged, and stirring and insulation are continued for aging reaction for 5 to 10 hours and then filtered, and the stirring speed is 300 to 800 r / min.

[0037] Furthermore, the solid-liquid ratio of the filter cake when adding water to the slurry is 1:10-30, the temperature of the complex EDTA complex is 40-70°C, the complex time is 50-70min, and the amount of EDTA added is EDTA and Ca in the slurry. 2+ Mg 2+ 2 to 3 times the theoretical amount of the reaction.

[0038] Furthermore, when adding the oxidant to react, the pH is controlled at 8.0-9.5 by adding an alkaline precipitant aqueous solution, the reaction temperature is controlled at 50-90° C., the reaction time is 2-4 hours, and the oxidant is air, oxygen or hydrogen peroxide.

[0039] Furthermore, the manganese tetraoxide filter cake is washed and then dried at 110-130° C. for 6-15 hours to obtain battery-grade manganese tetraoxide.

[0040] The method for recovering manganese from waste manganese lithium-ion batteries provided by the present invention first obtains copper-manganese liquid from waste manganese lithium-ion batteries, and then removes impurities from the copper-manganese liquid and prepares battery-grade manganese tetraoxide through a one-step reaction method or a two-step reaction method, which can not only effectively recover valuable metal manganese and reduce the manganese treatment cost of waste manganese lithium-ion batteries, but also can convert the recovered manganese into battery-grade manganese tetraoxide with high economic value, so that waste manganese lithium-ion batteries can be recycled again, thus realizing resource recycling. Moreover, the process is simple and easy to control, the reaction conditions are mild, easy to implement, the production cost is low, and it is easy to realize industrial production.

[0041] In addition, the method for recovering manganese from manganese-containing waste lithium-ion batteries provided by the present invention adopts EDTA complexation to remove calcium. Compared with the fluoride removal method widely adopted in the prior art, it can not only effectively remove calcium and magnesium ions in the system and reduce the impurity content in the product, but also does not introduce fluoride ions, which can effectively reduce process processing costs and reduce pollution to the environment.

[0042] At the same time, the method for recovering manganese from manganese-containing waste lithium-ion batteries provided by the present invention adopts a one-step reaction method or a two-step reaction method to prepare battery-grade manganese tetraoxide. The obtained battery-grade manganese tetraoxide has small particles, high purity, uniform particle size distribution, large tap density, and low specific surface area, which greatly improves the quality and application scope of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A flow chart of a method for recovering manganese from manganese-containing waste lithium-ion batteries provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0044] See also Figure 1 The present invention provides a method for recovering manganese from manganese-containing waste lithium-ion batteries, comprising the following steps:

[0045] Step 1) obtaining copper-manganese solution: obtaining copper-manganese solution from waste lithium-ion batteries containing manganese.

[0046] Wherein, obtaining copper-manganese solution comprises the following steps:

[0047] ① Reduction calcination: The positive electrode black powder separated from the manganese-containing waste lithium-ion battery is calcined at high temperature to obtain a calcined product;

[0048] ② Water leaching: The roasted product is leached in water to obtain manganese-containing water leaching residue and lithium-rich solution;

[0049] ③ Leaching: leaching the manganese-containing water leaching residue to obtain a manganese-containing leaching solution;

[0050] ④ Extraction: Use an extractant to extract, separate and remove impurities from the manganese-containing leaching solution to obtain copper-manganese solution.

[0051] The extraction is to use P2O4 as an extractant to extract the manganese-containing leaching solution to obtain a raffinate and a loaded organic phase, and the loaded organic phase is back-extracted using a 160-200g / L sulfuric acid solution to obtain a copper-manganese solution.

[0052] Step 2) copper removal: add a copper removal agent to the copper-manganese solution, and filter after the reaction to obtain a copper-removed solution.

[0053] Wherein, the copper removing agent is manganese powder or iron powder or a mixture of manganese powder and iron powder.

[0054] When using a copper remover to remove copper from copper-manganese liquid, the amount of copper remover added is 1.1 to 1.3 times the theoretical value of the reaction between the copper remover and the copper-manganese liquid.

[0055] In order to improve the reaction efficiency and make the reaction more complete, the reaction temperature is controlled at 50-70°C and the reaction time is 2-4 hours when the copper removal agent reacts with the copper-manganese solution. After the reaction is complete, the sponge copper and the copper removal solution are obtained by filtration. During the reaction, the following reactions occur:

[0056] Cu 2+ +Mn(Fe)=Cu+Mn 2+ (Fe 2+ ):

[0057] The main component of the sponge copper obtained is copper; after copper is removed, the liquid mainly contains calcium, magnesium and manganese.

[0058] Step 3) one-step reaction: a certain amount of pure water is added to the reaction kettle as the base liquid, and then heated to 50-90° C., and under stirring, the prepared copper removal liquid and alkaline precipitant aqueous solution are added to the reaction kettle in parallel, and the pH value of the reaction system is adjusted to between 4.5 and 8.0 by controlling the amount of the alkaline precipitant aqueous solution added, and after complete reaction, the crude manganese hydroxide filter cake is obtained by filtering.

[0059] Among them, when the copper removal liquid and the alkaline precipitant aqueous solution are added to the reactor in parallel, it is carried out under stirring conditions, and the stirring speed is controlled to be 300-800r / min. In addition, in order to control the reaction rate of manganese ions and hydroxide ions in the copper removal liquid, the addition speed of the copper removal liquid is controlled when the copper removal liquid is added to the reactor under stirring conditions, so that the addition time of the copper removal liquid is controlled to be 6-20h. After the addition is completed, the pH value of the mixed solution in the reactor is maintained between 4.5 and 8.0, and the temperature is maintained at 50-90°C, and the aging reaction is continued at a stirring speed of 300-800r / min for 5-10h. The following ion reactions occur during the reaction:

[0060] Mn 2+ +2OH - =Mn(OH)2

[0061] After the reaction is complete, the crude manganese hydroxide filter cake is obtained by filtration.

[0062] Step 4) removing calcium and magnesium: adding water to the crude manganese hydroxide filter cake to prepare a slurry, then adding the complex EDTA for complexation, and then filtering to obtain the manganese hydroxide filter cake.

[0063] When the crude manganese hydroxide filter cake is slurried with water, the solid-liquid ratio of the crude manganese hydroxide filter cake to water is 1:10-30, and then EDTA is added to the obtained slurry for complexation. Since EDTA has strong complexation, EDTA can coordinate with calcium and magnesium ions in the slurry to form a stable complex, thereby separating calcium and magnesium ions from other ions in the slurry.

[0064] In order to enable EDTA to fully and efficiently complex with calcium and magnesium ions in the slurry, the temperature during complexation is controlled at 40-70°C and the complexation time is 50-70 minutes.

[0065] In addition, in order to completely complex the calcium and magnesium ions in the slurry and effectively remove calcium and magnesium, the amount of EDTA added is controlled to be EDTA and Ca 2+ Mg 2+ The reaction is just 2 to 3 times the theoretical amount.

[0066] The present invention adopts EDTA complexation to remove calcium and magnesium. Compared with the fluoride removal method widely adopted in the prior art, it can not only effectively remove calcium and magnesium ions in the system and reduce the impurity content in the product, but also will not introduce fluoride ions, which can effectively reduce process processing costs and reduce pollution to the environment.

[0067] Step 5) Oxidation: Add water to the manganese hydroxide filter cake to prepare a slurry, add an oxidant, stir the reaction, and then filter to obtain a manganese tetraoxide filter cake.

[0068] When water is added to the manganese hydroxide filter cake to prepare the slurry, the solid-liquid ratio of the manganese hydroxide filter cake to water is 1:10-30, and then the slurry obtained by the slurry preparation is heated to 50-90°C, and the pH of the slurry is controlled at 8.0-9.5 by adding an alkaline precipitant aqueous solution, and then an oxidant is added to the slurry, and the slurry is stirred at a stirring speed of 300-800 r / min for reaction. The following ion reactions occur during the reaction:

[0069] 3Mn(OH)2-2e - =Mn3O4+2H + +2H2O

[0070] In order to make the reaction complete and efficient, the temperature during the reaction is controlled at 50-90°C, the reaction time is 2-4 hours, and after the reaction is complete, filtering can obtain a manganese tetraoxide filter cake.

[0071] Wherein, the oxidant is air, oxygen or hydrogen peroxide.

[0072] Step 6) washing and drying: washing and drying the manganese tetraoxide filter cake to obtain battery-grade manganese tetraoxide.

[0073] The manganese tetraoxide filter cake is washed and then dried at 110-130° C. for 6-15 hours to obtain battery-grade manganese tetraoxide.

[0074] The method for recovering manganese from manganese-containing waste lithium-ion batteries provided by the present invention can not only effectively recover valuable metallic manganese and reduce the manganese treatment cost of manganese-containing waste lithium-ion batteries, but also can convert the recovered manganese into battery-grade manganese tetraoxide with high economic value, so that the manganese-containing waste lithium-ion batteries can be recycled again, thus realizing the recycling of resources.

[0075] In addition, the battery-grade manganese tetraoxide obtained by the present invention has small particles, high purity, uniform particle size distribution, large tap density, and low specific surface area, which greatly improves the quality and application range of the product.

[0076] At the same time, the process of the invention is simple and easy to control, the reaction conditions are mild, easy to implement, the production cost is low, and it is easy to realize industrial production.

[0077] The present invention provides another method for recovering manganese from waste lithium-ion batteries containing manganese, comprising the following steps:

[0078] Step 1) obtaining copper-manganese solution: obtaining copper-manganese solution from waste lithium-ion batteries containing manganese.

[0079] Wherein, obtaining copper-manganese solution comprises the following steps:

[0080] ① Reduction calcination: The positive electrode black powder separated from the manganese-containing waste lithium-ion battery is calcined at high temperature to obtain a calcined product;

[0081] ② Water leaching: The roasted product is leached in water to obtain manganese-containing water leaching residue and lithium-rich solution;

[0082] ③ Leaching: leaching the manganese-containing water leaching residue to obtain a manganese-containing leaching solution;

[0083] ④ Extraction: Use an extractant to extract, separate and remove impurities from the manganese-containing leaching solution to obtain copper-manganese solution.

[0084] The extraction is to use P2O4 as an extractant to extract the manganese-containing leaching solution to obtain a raffinate and a loaded organic phase, and the loaded organic phase is back-extracted using a 160-200g / L sulfuric acid solution to obtain a copper-manganese solution.

[0085] Step 2) copper removal: add a copper removal agent to the copper-manganese solution, and filter after the reaction to obtain a copper-removed solution.

[0086] Wherein, the copper removing agent is manganese powder or iron powder or a mixture of manganese powder and iron powder.

[0087] When using a copper remover to remove copper from copper-manganese liquid, the amount of copper remover added is 1.1 to 1.3 times the theoretical value of the reaction between the copper remover and the copper-manganese liquid.

[0088] In order to improve the reaction efficiency and make the reaction more complete, the reaction temperature of the copper removal agent and the copper-manganese solution is controlled at 50-70°C and the reaction time is 2-4 hours. After the reaction is complete, the copper slag is filtered out to obtain the copper-removed solution.

[0089] Step 3) One-step reaction: pure water is added to the reaction kettle as the base liquid, and then heated to 50-90° C., and then the copper removal liquid and the alkaline precipitant aqueous solution are added at the same time, and the pH value of the reaction system is controlled at 4.5-8.0. After stirring for reaction, the crude manganese hydroxide filter cake is obtained by filtering.

[0090] Among them, when the copper removal liquid and the alkaline precipitant aqueous solution are added to the reactor in parallel, the stirring speed is controlled to be 300-800r / min, and the copper removal liquid is added to the reactor under stirring conditions. The addition speed of the copper removal liquid is controlled so that the addition time of the copper removal liquid is controlled to be 6-20h. After the addition is completed, the pH value of the mixed liquid in the reactor is maintained between 4.5 and 8.0, the temperature is maintained at 50-90°C, and the aging reaction is continued at a stirring speed of 300-800r / min for 5-10h. The following ion reactions occur during the reaction:

[0091] Mn 2+ +2OH - =Mn(OH)2

[0092] After the reaction is complete, the crude manganese hydroxide filter cake is obtained by filtration.

[0093] Step 4) secondary reaction: add water to the crude manganese hydroxide filter cake to prepare a slurry, add an oxidant, stir the reaction, and then filter to obtain a filter cake.

[0094] When water is added to the manganese hydroxide filter cake to prepare the slurry, the solid-liquid ratio of the manganese hydroxide filter cake to water is 1:10-30, and then the slurry obtained by the slurry preparation is heated to 50-90°C, and the pH of the slurry is controlled at 8.0-9.5 by adding an alkaline precipitant aqueous solution, and then an oxidant is added to the slurry, and the slurry is stirred at a stirring speed of 300-800 r / min for reaction. The following ion reactions occur during the reaction:

[0095] 3Mn(OH)2-2e - =Mn3O4+2H + +2H2O

[0096] In order to make the reaction complete and efficient, the temperature during the reaction is controlled at 50-90°C, the reaction time is 2-4 hours, and after the reaction is complete, filtering can obtain a manganese tetraoxide filter cake.

[0097] Wherein, the oxidant is air, oxygen or hydrogen peroxide.

[0098] Step 5) Removing calcium and magnesium: adding water to the filter cake to prepare the slurry, and then adding the complex EDTA for complexation, and then filtering to obtain the manganese tetraoxide filter cake.

[0099] When the manganese tetraoxide filter cake is added with water to prepare the slurry, the solid-liquid ratio of the manganese tetraoxide filter cake to water is 1:10-30, and then EDTA is added to the obtained slurry for complexation. Since EDTA has strong complexation, EDTA can coordinate with calcium and magnesium ions in the slurry to form a stable complex, thereby separating calcium and magnesium ions from other ions in the slurry.

[0100] In order to enable EDTA to fully and efficiently complex with calcium and magnesium ions in the slurry, the temperature during complexation is controlled at 40-70°C and the complexation time is 50-70 minutes.

[0101] In addition, in order to completely complex the calcium and magnesium ions in the slurry and effectively remove calcium and magnesium, the amount of EDTA added is controlled to be EDTA and Ca 2+ Mg 2+ The reaction is just 2 to 3 times the theoretical amount.

[0102] The present invention adopts EDTA complexation to remove calcium and magnesium. Compared with the fluoride removal method widely adopted in the prior art, it can not only effectively remove calcium and magnesium ions in the system and reduce the impurity content in the product, but also will not introduce fluoride ions, which can effectively reduce process processing costs and reduce pollution to the environment.

[0103] Step 6) washing and drying: washing and drying the manganese tetraoxide filter cake to obtain battery-grade manganese tetraoxide.

[0104] The manganese tetraoxide filter cake is washed and then dried at 110-130° C. for 6-15 hours to obtain battery-grade manganese tetraoxide.

[0105] The method for recovering manganese from manganese-containing waste lithium-ion batteries provided by the present invention can not only effectively recover valuable metallic manganese and reduce the manganese treatment cost of manganese-containing waste lithium-ion batteries, but also can convert the recovered manganese into battery-grade manganese tetraoxide with high economic value, so that the manganese-containing waste lithium-ion batteries can be recycled again, thus realizing the recycling of resources.

[0106] In addition, the battery-grade manganese tetraoxide obtained by the present invention has small particles, high purity, uniform particle size distribution, large tap density, and low specific surface area, which greatly improves the quality and application range of the product.

[0107] At the same time, the process of the invention is simple and easy to control, the reaction conditions are mild, easy to implement, the production cost is low, and it is easy to realize industrial production.

[0108] The present invention also provides another method for recovering manganese from manganese-containing waste lithium-ion batteries, comprising the following steps:

[0109] Step 1) obtaining copper-manganese solution: obtaining copper-manganese solution from waste lithium-ion batteries containing manganese;

[0110] Wherein, obtaining copper-manganese solution comprises the following steps:

[0111] ① Reduction calcination: The positive electrode black powder separated from the manganese-containing waste lithium-ion battery is calcined at high temperature to obtain a calcined product;

[0112] ② Water leaching: The roasted product is leached in water to obtain manganese-containing water leaching residue and lithium-rich solution;

[0113] ③ Leaching: leaching the manganese-containing water leaching residue to obtain a manganese-containing leaching solution;

[0114] ④ Extraction: Use an extractant to extract, separate and remove impurities from the manganese-containing leaching solution to obtain copper-manganese solution.

[0115] The extraction is to use P2O4 as an extractant to extract the manganese-containing leaching solution to obtain a raffinate and a loaded organic phase, and the loaded organic phase is back-extracted using a 160-200g / L sulfuric acid solution to obtain a copper-manganese solution.

[0116] Step 2) copper removal: add a copper removal agent to the copper-manganese solution, and filter after the reaction to obtain a copper-removed solution.

[0117] Wherein, the copper removing agent is manganese powder or iron powder or a mixture of manganese powder and iron powder.

[0118] When using a copper remover to remove copper from copper-manganese liquid, the amount of copper remover added is 1.1 to 1.3 times the theoretical value of the reaction between the copper remover and the copper-manganese liquid.

[0119] In order to improve the reaction efficiency and make the reaction more complete, the reaction temperature of the copper removal agent and the copper-manganese solution is controlled at 50-70°C and the reaction time is 2-4 hours. After the reaction is complete, the copper slag is filtered out to obtain the copper-removed solution.

[0120] Step 3) Oxidation: pure water is added to the reaction kettle as the base liquid, and then heated to 50-90° C., and then the copper removal liquid and alkaline precipitant aqueous solution are added at the same time, and then an oxidant is added, and the pH value of the reaction system is controlled at 4.5-9.5. After stirring for reaction, the filter is filtered to obtain a filter cake.

[0121] The copper removal solution and the alkaline precipitant aqueous solution are added to the reactor in parallel under stirring conditions, and the stirring speed is controlled to be 300-800 r / min. Moreover, the copper removal solution is added to the reactor under stirring conditions, and the addition speed of the copper removal solution is controlled to control the addition time of the copper removal solution to be 6-20 hours. After the addition is completed, the pH value of the mixed solution in the reactor is maintained between 4.5 and 8.0, and the temperature is maintained at 50-90°C, and the aging reaction is continued at a stirring speed of 300-800 r / min for 5-10 hours. The following ion reactions occur during the reaction:

[0122] Mn 2+ +2OH - =Mn(OH)2.

[0123] Then add the oxidant to the mixture in the reactor and stir the mixture at a stirring speed of 300-800 r / min. The following ion reactions occur during the reaction:

[0124] 3Mn(OH)2-2e - =Mn3O4+2H + +2H2O

[0125] In order to make the reaction complete and efficient, the temperature during the reaction is controlled at 50-90°C, the reaction time is 2-4 hours, and after the reaction is complete, a filter cake can be obtained by filtering.

[0126] Wherein, the oxidant is air, oxygen or hydrogen peroxide.

[0127] Step 4) Removing calcium and magnesium: adding water to the filter cake to prepare the slurry, and then adding the complex EDTA for complexation, and then filtering to obtain the manganese tetraoxide filter cake.

[0128] When the filter cake is added with water to prepare the slurry, the solid-liquid ratio of the filter cake to water is 1:10-30, and then EDTA is added to the obtained slurry for complexation. Since EDTA has strong complexation, EDTA can coordinate with calcium and magnesium ions in the slurry to form a stable complex, thereby separating calcium and magnesium ions from other components in the slurry.

[0129] In order to enable EDTA to fully and efficiently complex with calcium and magnesium ions in the slurry, the temperature during complexation is controlled at 40-70°C and the complexation time is 50-70 minutes.

[0130] In addition, in order to completely complex the calcium and magnesium ions in the slurry and effectively remove calcium and magnesium, the amount of EDTA added is controlled to be EDTA and Ca 2+ Mg 2+ The reaction is just 2 to 3 times the theoretical amount.

[0131] The present invention adopts EDTA complexation to remove calcium and magnesium. Compared with the fluoride removal method widely adopted in the prior art, it can not only effectively remove calcium and magnesium ions in the system and reduce the impurity content in the product, but also will not introduce fluoride ions, which can effectively reduce process processing costs and reduce pollution to the environment.

[0132] Step 5) washing and drying: washing and drying the manganese tetraoxide filter cake to obtain battery-grade manganese tetraoxide.

[0133] The manganese tetraoxide filter cake is washed and then dried at 110-130° C. for 6-15 hours to obtain battery-grade manganese tetraoxide.

[0134] The method for recovering manganese from manganese-containing waste lithium-ion batteries provided by the present invention can not only effectively recover valuable metallic manganese and reduce the manganese treatment cost of manganese-containing waste lithium-ion batteries, but also can convert the recovered manganese into battery-grade manganese tetraoxide with high economic value, so that the manganese-containing waste lithium-ion batteries can be recycled again, thus realizing the recycling of resources.

[0135] In addition, the battery-grade manganese tetraoxide obtained by the present invention has small particles, high purity, uniform particle size distribution, large tap density, and low specific surface area, which greatly improves the quality and application range of the product.

[0136] At the same time, the process of the invention is simple and easy to control, the reaction conditions are mild, easy to implement, the production cost is low, and it is easy to realize industrial production.

[0137] The following three embodiments are used to specifically illustrate the methods for recovering manganese from three manganese-containing waste lithium-ion batteries provided by the present invention.

[0138] Example 1

[0139] The present invention provides a method for recovering manganese from manganese-containing waste lithium-ion batteries, and the specific steps are as follows:

[0140] (1) Obtaining a manganese-containing leaching solution: Positive electrode black powder is obtained from waste lithium-ion batteries by disassembling, crushing and separating. 500 g of the positive electrode black powder is calcined at 650° C. for 2 h to obtain a calcined product. The product is crushed by a crusher and wet-milled for 1.5 h. After ball milling, the slurry is hydrated to 3 L and carbon dioxide is passed through the water to extract lithium for 2 h. 375 g of water leaching residue (dry basis) and a lithium-rich solution are obtained by filtration. The lithium-rich solution is used to prepare lithium products. 200 g of water leaching residue (dry basis) is added with 600 ml of bottom water and 200 ml of concentrated sulfuric acid, and 60 ml of hydrogen peroxide is slowly added, with a pH of 1.5, to obtain a manganese-containing leaching solution.

[0141] (2) Extraction: The pH of the manganese-containing leaching solution is adjusted to 5.0, and the manganese-containing leaching solution is mixed with P2O4 treated with lithium hydroxide saponification and sulfonated kerosene for extraction and separation to obtain a raffinate and a loaded organic phase; the loaded organic phase is stripped with a 200 g / L dilute sulfuric acid solution to obtain a copper-manganese solution and a stripped organic phase, and the stripped organic phase is returned to the extraction step for recycling.

[0142] (3) Copper removal: Take 600 ml of copper-manganese liquid, add 4 g of manganese powder, the addition amount is 1.2 times the theoretical addition amount, the reaction temperature is 50°C, the reaction time is 2 h, after the reaction is completed, filter out the copper slag to obtain the copper-removed liquid.

[0143] (4) One-step reaction: pure water was added to the reactor as the bottom liquid, heated to 70°C, and stirred at 500 r / min to obtain the copper-free solution and the mixed aqueous solution of sodium hydroxide and ammonia (OH - The concentration of 5 mol / L) was added to the reactor in parallel, and the pH value of the reaction system was controlled to be 7.0 by adjusting the amount of the mixed aqueous solution added. The addition time of the manganese sulfate solution was 12 hours. After the addition was completed, the pH value was controlled unchanged, and the stirring and heat preservation were continued for 7 hours, and the crude manganese hydroxide filter cake was obtained by filtration.

[0144] (5) Removal of calcium and magnesium: Take 100g of crude manganese hydroxide filter cake, add 2L of water to prepare the slurry, add EDTA to the slurry, react at 50℃ for 60min, and the amount of EDTA added is 1:100g of Ca in the solution. 2+ Mg 2+ The stirring speed is 110r / min, and after the reaction is completed, the manganese hydroxide filter cake is obtained by filtration.

[0145] (6) Oxidation: Add 2 L of water to the manganese hydroxide filter cake for slurry preparation, heat to 60° C., and blow air into the mixture for oxidation at a stirring speed of 500 r / min. At the same time, add an aqueous sodium hydroxide solution to control the pH to 9.5. The mixture is reacted for 4 h. After the reaction is complete, the manganese tetraoxide filter cake is obtained by filtering.

[0146] (7) The manganese tetraoxide filter cake obtained by filtration was first washed with deionized water for several times, and then the manganese tetraoxide filter cake obtained by filtration was dried at 120° C. for 12 h to obtain battery-grade manganese tetraoxide.

[0147] The chemical composition and related properties of the battery-grade manganese tetraoxide obtained in the embodiment of the present invention were tested, and the test results are shown in Table 1.

[0148] Example 2

[0149] The present invention provides a method for recovering manganese from manganese-containing waste lithium-ion batteries, and the specific steps are as follows:

[0150] (1) Obtaining a manganese-containing leaching solution: Positive electrode black powder is obtained from waste lithium-ion batteries by disassembling, crushing and separating. 500 g of the positive electrode black powder is calcined at 650° C. for 2 h to obtain a calcined product. The product is crushed by a crusher and wet-milled for 1.5 h. After ball milling, the slurry is hydrated to 3 L and carbon dioxide is passed through the water to extract lithium for 2 h. 375 g of water leaching residue (dry basis) and a lithium-rich solution are obtained by filtration. The lithium-rich solution is used to prepare lithium products. 200 g of water leaching residue (dry basis) is added with 600 ml of bottom water and 200 ml of concentrated sulfuric acid, and 60 ml of hydrogen peroxide is slowly added, with a pH of 1.5, to obtain a manganese-containing leaching solution.

[0151] (2) Extraction: The pH of the manganese-containing leaching solution is adjusted to 5.0, and the manganese-containing leaching solution is mixed with P2O4 treated with lithium hydroxide saponification and sulfonated kerosene for extraction and separation to obtain a raffinate and a loaded organic phase; the loaded organic phase is stripped with a 200 g / L dilute sulfuric acid solution to obtain a copper-manganese solution and a stripped organic phase, and the stripped organic phase is returned to the extraction step for recycling.

[0152] (3) Copper removal: Take 600 ml of copper-manganese liquid, add 4 g of manganese powder, the addition amount is 1.2 times the theoretical addition amount, the reaction temperature is 50°C, the reaction time is 2 h, after the reaction is completed, filter out the copper slag to obtain the copper-removed liquid.

[0153] (4) One-step reaction: pure water was added to the reactor as the bottom liquid, heated to 70°C, and stirred at 500 r / min to obtain the copper-free solution and the mixed aqueous solution of sodium hydroxide and ammonia (OH - The concentration of 5 mol / L) was added to the reactor in parallel, and the pH value of the reaction system was controlled to be 7.0 by adjusting the amount of the mixed aqueous solution added. The addition time of the manganese sulfate solution was 12 hours. After the addition was completed, the pH value was controlled unchanged, and the stirring and heat preservation were continued for 7 hours, and the crude manganese hydroxide filter cake was obtained by filtration.

[0154] (5) Secondary reaction: 100 g of crude manganese hydroxide filter cake was taken, 2 L of water was added for slurry preparation, the mixture was heated to 60° C., and air was blown into the mixture for oxidation under stirring at 500 r / min. After reacting for 4 h, the mixture was filtered to obtain a filter cake.

[0155] (6) Removal of calcium and magnesium: Add 2L of the filter cake to prepare the slurry, and then add the complex EDTA for complexation. React at 50°C for 60 minutes. The amount of EDTA added is the amount of Ca in the solution. 2+ Mg 2+ The stirring speed is 110r / min, and the manganese tetraoxide filter cake is obtained by filtration.

[0156] (7) Washing and drying: The manganese tetraoxide filter cake is washed several times with deionized water and dried at 120° C. for 12 h to obtain battery-grade manganese tetraoxide.

[0157] The chemical composition and related properties of the battery-grade manganese tetraoxide obtained in the embodiment of the present invention were tested, and the test results are shown in Table 1.

[0158] Example 3

[0159] The present invention provides a method for recovering manganese from manganese-containing waste lithium-ion batteries, and the specific steps are as follows:

[0160] (1) Obtaining a manganese-containing leaching solution: Positive electrode black powder is obtained from waste lithium-ion batteries by disassembling, crushing and separating. 500 g of the positive electrode black powder is calcined at 650° C. for 2 h to obtain a calcined product. The product is crushed by a crusher and wet-milled for 1.5 h. After ball milling, the slurry is hydrated to 3 L and carbon dioxide is passed through the water to extract lithium for 2 h. 375 g of water leaching residue (dry basis) and a lithium-rich solution are obtained by filtration. The lithium-rich solution is used to prepare lithium products. 200 g of water leaching residue (dry basis) is added with 600 ml of bottom water and 200 ml of concentrated sulfuric acid, and 60 ml of hydrogen peroxide is slowly added, with a pH of 1.5, to obtain a manganese-containing leaching solution.

[0161] (2) Extraction: The pH of the manganese-containing leaching solution is adjusted to 5.0, and the manganese-containing leaching solution is mixed with P2O4 treated with lithium hydroxide saponification and sulfonated kerosene for extraction and separation to obtain a raffinate and a loaded organic phase; the loaded organic phase is stripped with a 200 g / L dilute sulfuric acid solution to obtain a copper-manganese solution and a stripped organic phase, and the stripped organic phase is returned to the extraction step for recycling.

[0162] (3) Copper removal: Take 600 ml of copper-manganese liquid, add 4 g of manganese powder, the addition amount is 1.2 times the theoretical addition amount, the reaction temperature is 50°C, the reaction time is 2 h, after the reaction is completed, filter out the copper slag to obtain the copper-removed liquid.

[0163] (4) Oxidation: pure water was added to the reactor as the bottom liquid, heated to 70°C, and stirred at 500 r / min to mix the prepared copper removal solution and the mixed aqueous solution of sodium hydroxide and ammonia (OH - The concentration of manganese sulfate solution is 5 mol / L) and added to the reactor in parallel, and air is blown in for oxidation. The pH value of the reaction system is controlled to be 9.5 by adjusting the amount of the mixed aqueous solution added. The addition time of manganese sulfate solution is 12 h. After the addition is completed, the pH value is controlled unchanged, and stirring and insulation are continued for 7 h, and the filter cake is obtained by filtration.

[0164] (5) Removal of calcium and magnesium: Take 100g of filter cake, add 2L of water to the filter cake for slurry preparation, and then add EDTA for complexation, react at 50℃ for 60min. The amount of EDTA added is the amount of Ca in the solution. 2+ Mg 2+ The stirring speed is 110r / min, and the manganese tetraoxide filter cake is obtained by filtration.

[0165] (6) Washing and drying: The manganese tetraoxide filter cake is washed several times with deionized water, and the filtered product is dried at 120° C. for 12 h to obtain battery-grade manganese tetraoxide.

[0166] The chemical composition and related properties of the battery-grade manganese tetraoxide obtained in the embodiment of the present invention were tested, and the test results are shown in Table 1.

[0167] Table 1

[0168]

[0169] It can be seen from Table 1 that the performance of the battery-grade manganese manganese tetroxide obtained by the three methods for recovering manganese from manganese-containing waste lithium-ion batteries provided in the three embodiments of the present invention can meet the standards of battery-grade manganese manganese tetroxide in all aspects.

[0170] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for recovering manganese from waste lithium-ion batteries containing manganese, characterized in that: The steps include: Obtaining copper-manganese liquid from manganese-containing waste lithium-ion batteries; Adding a copper removal agent to the copper-manganese solution, filtering after the reaction to obtain a copper-removed solution; After adding pure water to the reaction kettle and heating it to 50-90° C., adding the copper removal solution and the alkaline precipitant aqueous solution at the same time, controlling the pH value of the reaction system to be 4.5-8.0, stirring the reaction, and filtering to obtain a crude manganese hydroxide filter cake; Add water to the crude manganese hydroxide filter cake to prepare the slurry, then add the complex EDTA for complexation, and then filter to obtain the manganese hydroxide filter cake; Add water to the manganese hydroxide filter cake to prepare the slurry, add an oxidant, stir the reaction, and then filter to obtain the manganese tetraoxide filter cake; The manganese tetraoxide filter cake is washed and dried to obtain battery-grade manganese tetraoxide.

2. A method for recovering manganese from waste lithium-ion batteries containing manganese, characterized in that: The steps include: Obtaining copper-manganese liquid from manganese-containing waste lithium-ion batteries; Adding a copper removal agent to the copper-manganese solution, filtering after the reaction to obtain a copper-removed solution; After adding pure water to the reaction kettle and heating it to 50-90° C., adding the copper removal solution and the alkaline precipitant aqueous solution at the same time, controlling the pH value of the reaction system to be 4.5-8.0, stirring the reaction, and filtering to obtain a crude manganese hydroxide filter cake; Add water to the crude manganese hydroxide filter cake to prepare a slurry, add an oxidant, stir the reaction, and then filter to obtain a filter cake; Add water to the filter cake to prepare the slurry, then add the complex EDTA for complexation, and then filter to obtain the manganese tetraoxide filter cake; The manganese tetraoxide filter cake is washed and dried to obtain battery-grade manganese tetraoxide.

3. A method for recovering manganese from waste lithium-ion batteries containing manganese, characterized in that: The steps include: Obtaining copper-manganese liquid from manganese-containing waste lithium-ion batteries; Adding a copper removal agent to the copper-manganese solution, filtering after the reaction to obtain a copper-removed solution; After adding pure water to the reaction kettle and heating it to 50-90°C, adding the copper removal solution and alkaline precipitant aqueous solution at the same time, and then adding an oxidant, controlling the pH value of the reaction system to 4.5-9.5, stirring the reaction, and filtering to obtain a filter cake; Add water to the filter cake to prepare the slurry, then add the complex EDTA for complexation, and then filter to obtain the manganese tetraoxide filter cake; The manganese tetraoxide filter cake is washed and dried to obtain battery-grade manganese tetraoxide.

4. The method for recovering manganese from manganese-containing waste lithium-ion batteries according to any one of claims 1 to 3, characterized in that: The copper-manganese solution is obtained by the following steps: Reduction calcination: The positive electrode black powder separated from the manganese-containing waste lithium-ion battery is calcined at high temperature to obtain a calcined product; Water leaching: leaching the roasted product in water to obtain manganese-containing water leaching residue and lithium-rich solution; Leaching: leaching the manganese-containing water leaching residue to obtain a manganese-containing leaching solution; Extraction: Use an extractant to extract, separate and remove impurities from the manganese-containing leaching solution to obtain copper-manganese solution.

5. The method for recovering manganese from manganese-containing waste lithium-ion batteries according to claim 4, characterized in that: The extraction is to use P2O4 as an extractant to extract the manganese-containing leaching solution to obtain a raffinate and a loaded organic phase, and the loaded organic phase is back-extracted with a 160-200 g / L sulfuric acid solution to obtain a copper-manganese solution.

6. The method for recovering manganese from waste lithium-ion batteries containing manganese according to claim 4, characterized in that: The copper removal agent is one or both of manganese powder and iron powder, the amount of the copper removal agent added is 1.1 to 1.3 times the theoretical value of the reaction between the copper removal agent and the copper-manganese solution, the reaction temperature between the copper removal agent and the copper-manganese solution is 50 to 70° C., and the reaction time is 2 to 4 hours; The alkaline precipitant in the alkaline precipitant aqueous solution is one or both of sodium hydroxide and ammonia water; the concentration of the alkaline precipitant aqueous solution is 1-10 mol / L.

7. The method for recovering manganese from waste lithium-ion batteries containing manganese according to claim 4, characterized in that: The copper-removed liquid is added to the reaction kettle under stirring conditions, and the addition time of the copper-removed liquid is 6 to 20 hours. After the addition is completed, the pH value and temperature are kept unchanged, and stirring and insulation are continued for aging reaction for 5 to 10 hours, and then filtering is performed, and the stirring speed is 300 to 800 r / min.

8. The method for recovering manganese from waste lithium-ion batteries containing manganese according to claim 4, characterized in that: The solid-liquid ratio of the filter cake when adding water to the slurry is 1:10-30, the temperature of the complex EDTA complex is 40-70°C, the complex time is 50-70min, and the amount of EDTA added is EDTA and Ca in the slurry. 2+ Mg 2+ 2 to 3 times the theoretical amount of the reaction.

9. The method for recovering manganese from waste lithium-ion batteries containing manganese according to claim 4, characterized in that: When adding the oxidant to react, the pH is controlled at 8.0-9.5 by adding an alkaline precipitant aqueous solution, the reaction temperature is controlled at 50-90° C., the reaction time is 2-4 hours, and the oxidant is air, oxygen or hydrogen peroxide.

10. The method for recovering manganese from waste lithium-ion batteries containing manganese according to claim 4, characterized in that: The manganese tetraoxide filter cake is washed and dried at 110-130° C. for 6-15 hours to obtain battery-grade manganese tetraoxide.

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