A method for preparing a phosphorus removal agent by mixing waste battery recycled iron-aluminum slag with pyrolusite.

Abstract

This disclosure relates to a method for preparing a phosphorus removal agent by mixing iron-aluminum slag from waste battery recycling with pyrolusite. The method includes the following steps: grinding and crushing the iron-aluminum slag obtained during the waste battery recycling process to obtain fine iron-aluminum slag; activating and modifying the fine iron-aluminum slag to obtain modified iron-aluminum slag; pulverizing and acid-leaching the pyrolusite, filtering to obtain solid MnO2; adding a chelating agent, KMnO4 solution, dilute sulfuric acid solution, and hydrazine hydrate to the solid MnO2, filtering to obtain modified solid MnO2; mixing the modified iron-aluminum slag and modified solid MnO2 to obtain an iron-aluminum slag-manganese dioxide mixture, followed by blanking and sintering to obtain a phosphorus removal adsorbent. This disclosure achieves high-value utilization of Fe and Al in waste batteries by modifying the iron-aluminum slag obtained from waste battery recycling, modifying natural pyrolusite, and mixing the two to prepare a phosphorus removal agent, while also making full use of low-quality pyrolusite, thus enhancing resource utilization efficiency.

Description

Technical Field

[0001] This disclosure relates to a method for preparing a phosphorus removal agent by mixing waste battery recycled iron-aluminum slag with pyrolusite. Background Technology

[0002] With the improvement and maturation of my country's new energy vehicle technology, the sales of ternary lithium-ion battery-powered vehicles in my country have continued to rise. As time goes by, the amount of waste batteries scrapped each year is also enormous.

[0003] Lithium-ion batteries have an average lifespan of 500-1000 cycles, with a service life of about 3 years. Therefore, the recycling and disposal of used lithium-ion batteries has received widespread attention. With the continuous increase in demand for power batteries, and given their limited lifespan, the number of power batteries destined for obsolescence will be enormous in the future.

[0004] Currently, the recycling and impurity removal processes for waste batteries generally employ wet processes. These processes generate nickel-cobalt-manganese-lithium metal sulfate solutions, which contain certain amounts of iron and aluminum ions. Therefore, removing iron and aluminum from these solutions is a crucial step in lithium battery recycling. Currently, in wet processes, Fe and Al are typically converted into FeOOH, Fe(OH)3, AlOOH, and Al(OH)3. However, FeOOH, Fe(OH)3, AlOOH, and Al(OH)3 have low utilization value and are difficult to utilize independently. Summary of the Invention

[0005] Based on this, the purpose of this disclosure is to provide a method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite, so as to achieve high-value utilization of Fe and Al in waste batteries, while also making full use of low-quality pyrolusite and enhancing resource utilization efficiency.

[0006] The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in this disclosure includes the following steps:

[0007] The iron-aluminum slag obtained from the grinding and crushing process of waste battery recycling is used to obtain fine iron-aluminum slag.

[0008] The fine iron-aluminum slag is activated and modified to obtain modified iron-aluminum slag;

[0009] The pyrolusite was crushed, acid-leached, and filtered to obtain solid MnO2.

[0010] A chelating agent, KMnO4 solution, dilute sulfuric acid solution, and hydrazine hydrate were added to the MnO2 solid, and the mixture was filtered to obtain modified MnO2 solid.

[0011] The modified iron-aluminum slag and modified MnO2 solid were mixed to obtain an iron-aluminum slag manganese dioxide mixture, which was then formed and sintered to obtain a phosphorus removal adsorbent.

[0012] Pyrolusite, whose main component is manganese dioxide, is a common manganese mineral with advantages such as large quantity, low price, no pollution, and strong stability. At the same time, pyrolusite has good surface adsorption effect, redox effect and channel effect. In addition, pyrolusite also contains transition metal elements such as Ni, Ti and Co, which have catalytic oxidation effect. However, unmodified pyrolusite cannot adsorb phosphorus.

[0013] This disclosure achieves high-value utilization of Fe and Al in waste batteries by modifying the iron-aluminum slag obtained from waste battery recycling, modifying natural pyrolusite, and sintering the two together to obtain a loose and porous phosphorus adsorbent. At the same time, it makes full use of low-quality pyrolusite and enhances resource utilization efficiency.

[0014] The phosphorus removal adsorbent prepared in this disclosure has uniform particle size, high strength, numerous micropores on its surface, and a crisscrossing internal network, exhibiting strong adsorption capacity. It is less affected by the pH of the water body and has a long service life. The process is simple and low-cost, achieving highly efficient phosphorus removal without generating secondary pollutants. It is easy to apply industrially and has excellent application prospects. The material can not only be used as an adsorbent for phosphorus-containing wastewater but also for phosphorus removal in natural water bodies and controlling phosphorus release from sediments. It also makes full use of low-grade pyrolusite, enhancing resource utilization efficiency.

[0015] As a preferred embodiment, the method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in this disclosure is characterized by further comprising the following steps:

[0016] The crushed and acid-leached soft manganese ore, after filtration, also yields a solution containing Fe and Al.

[0017] Iron powder was added to the Fe and Al solution to obtain a Fe(II) and Al solution;

[0018] When the modified iron-aluminum slag and modified MnO2 solid are mixed, a solution containing Fe(II) and Al is also added. After mixing, NaOH solution is added to adjust the pH, and air is introduced at the same time. After filtration, filter residue is obtained, and then the mixture is made into a blank.

[0019] By fully utilizing the Fe and Al ions in the acid leaching solution of pyrolusite, the adsorption performance is further enhanced by allowing them to adhere to the surface of iron-aluminum slag and pyrolusite.

[0020] As a preferred embodiment, the blank preparation method described in this disclosure requires the addition of charcoal powder. The filter residue and the charcoal powder are mixed in a mass ratio of 2 to 3:1 to form a slurry. The slurry is then added to a mold to obtain the molding material, which facilitates subsequent sintering.

[0021] As a preferred embodiment, the pH adjustment range described in this disclosure is 3.8-4.5, which converts Fe and Al ions into aluminum hydroxide (AlOOH) and iron hydroxide (FeOOH); on the one hand, Al... 3+ Fe 3+ With PO4 3- On the other hand, Al 3+ Hydrolysis forms mononuclear complexes such as AlOOH and FeOOH, which further condense into a series of polynuclear complexes Al through collisional condensation. n (OH) m (3n-m)+ (n>1, m≤3n), these aluminum polynuclear complexes often have high positive charge and specific surface area, which can quickly adsorb negatively charged impurities in water, neutralize colloidal charge, reduce colloidal potential, coagulate and precipitate, thus showing good phosphorus removal effect.

[0022] As a preferred embodiment, the charcoal powder disclosed herein includes activated carbon. Activated carbon can play a role in making the material porous during the reaction process; during the subsequent sintering process, the activated carbon in the reacted portion can create passageways and expand the reaction area; the activated carbon that has not undergone reaction can play an adsorption role.

[0023] As a preferred embodiment, this disclosure uses acid to activate the fine iron-aluminum slag and uses an aluminate coupling agent to modify the fine iron-aluminum slag. Acid activation removes organic matter and other impurities from the iron-aluminum slag, clears pores, and improves the specific surface area and surface activity of the iron-aluminum slag. Modification with an aluminate coupling agent imparts more active sites and stronger heavy metal binding to the iron-aluminum slag.

[0024] As a preferred embodiment, the chelating agent disclosed herein is one or more of citric acid, oxalic acid, salicylic acid, and tartaric acid, with a concentration of 0.5–1 mol / L; the KMnO4 solution concentration is 0.1–0.3 mol / L; the dilute sulfuric acid solution concentration is 60–80 g / L; and the hydrazine hydrate concentration is 10–20 g / L. The chelating agent can react with Mn... 2+ A complex is formed, which strongly adsorbs onto the surface of inorganic metal oxides such as MnO2. The complexing effect of the chelating agent, combined with the dissolving effect of sulfuric acid, works synergistically to dissolve the surface of solid MnO2. Furthermore, the oxidizing properties of KMnO4 further improve the surface properties of solid MnO2, thereby enhancing its adsorption capacity. Simultaneously, the synergistic effect of the dissolving effect of dilute sulfuric acid and the reducing dissolution effect of a small amount of hydrazine hydrate further dissolves impurities within the pores of solid MnO2, renewing the intact crystalline surface layer and forming a new, nascent surface layer, thus improving the interfacial adsorption capacity of solid MnO2.

[0025] As a preferred embodiment, the acid leaching solution described in this disclosure is a 100-300 g / L sulfuric acid solution; the MnO2 solid obtained after filtration needs to be dried at 60-80°C for 120-240 min. Sulfuric acid can dissolve Fe and Al ions in pyrolusite, thus initially clearing the pores of the pyrolusite.

[0026] As a preferred embodiment, the grinding and crushing process described in this disclosure uses a sand mill. During grinding and crushing, the sand mill rotates at a speed of 200–300 r / min, the grinding time is 30–60 min, and the volume ratio of grinding balls to raw materials is 3–5:1. The fine iron-aluminum slag has a particle size of 60–80 mesh. Crushing and grinding can reduce the particle size of the iron-aluminum slag, facilitating subsequent activation and modification.

[0027] As a preferred embodiment, the sintering process described in this disclosure is carried out under an inert atmosphere, with a sintering temperature of 100℃ to 200℃ and a sintering time of 1 to 3 hours. The inert atmosphere prevents oxidation during the sintering process; the resulting phosphorus removal adsorbent has higher mechanical strength.

[0028] As a preferred embodiment, after blank preparation and before sintering, the present disclosure further includes air drying, which is performed by placing the blank in the environment for natural air drying for 8-12 hours. Natural air drying facilitates subsequent transfer and collection and reduces energy consumption.

[0029] As a preferred embodiment, the present disclosure further includes drying after air drying and before sintering. The drying process is carried out in an oven at a temperature of 100-110°C for 30-60 minutes. The temperature is primarily to evaporate the free water present in the product.

[0030] To better understand and implement this disclosure, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0031] Figure 1 This is a flowchart of a method for preparing a phosphorus removal agent by mixing waste battery recycled iron and aluminum slag with pyrolusite. Detailed Implementation

[0032] like Figure 1 As shown, a method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite includes the following steps:

[0033] The iron-aluminum slag obtained from the recycling process of waste batteries is crushed and ground to obtain fine iron-aluminum slag.

[0034] The fine iron-aluminum slag is activated and modified to obtain modified iron-aluminum slag;

[0035] The natural pyrolusite was crushed, acid-leached, and filtered to obtain solid MnO2 and a solution containing Fe and Al.

[0036] A chelating agent, KMnO4 solution, dilute sulfuric acid solution, and hydrazine hydrate were added to the MnO2 solid, and the mixture was filtered to obtain modified MnO2 solid.

[0037] Iron powder was added to the Fe and Al solution so that all iron ions in the solution existed in the form of ferrous iron, thus obtaining a Fe(II) and Al solution.

[0038] The modified iron-aluminum slag and the modified MnO2 solid were added to the Fe(II) and Al-containing solution, mixed, and then NaOH solution was added to adjust the pH. At the same time, air was introduced to precipitate the iron and aluminum ions in the solution, resulting in a mixture of iron-aluminum slag and manganese dioxide.

[0039] The iron-aluminum slag manganese dioxide mixture is mixed with charcoal powder to form a slurry. The slurry is then added to a mold to form a blank, followed by air drying, drying, and sintering to obtain a phosphorus removal adsorbent.

[0040] Example 1

[0041] This disclosure provides a method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite, including the following steps:

[0042] 1. In the lithium-ion battery recycling process, the iron and aluminum slag obtained from the wet leaching process is dried, crushed, and ground. The grinding mill speed is 200 r / min, the grinding time is 30 min, and the volume ratio of grinding balls to raw materials is 3:1. The product is then screened to 60 mesh fine iron and aluminum slag.

[0043] 2. Aluminate coupling agents are used to modify iron-aluminum slag, giving the iron-aluminum slag structure more active sites and stronger heavy metal binding. At the same time, acid activation is used before modifying the iron-aluminum slag with aluminate coupling agents to remove organic matter and other impurities in the iron-aluminum slag, clear the pores, and improve the specific surface area and surface activity of the iron-aluminum slag.

[0044] 3. Pyrolusite is generally associated with oxides such as Al and Fe2O3. Pyrolusite can be subjected to preliminary sulfation treatment by using a 100g / L sulfuric acid solution to dissolve Fe and Al.

[0045] 4. The solution of H2SO4 treated with pyrolusite was subjected to solid-liquid separation and dried at 60℃ for 120 min to obtain relatively pure dry MnO2 solid.

[0046] 5. Citric acid is a highly efficient chelating agent that can form complexes and strongly adsorb on the surface of MnO2. Adding 0.5 mol / L citric acid solution dissolves the surface of MnO2, and the oxidizing properties of 0.1 mol / L KMnO4 further improve the surface properties, thereby enhancing its surface adsorption capacity.

[0047] 6. The leaching effect of 60g / L dilute sulfuric acid and the reducing dissolution effect of 10g / L hydrazine hydrate work synergistically to dissolve the impurities that are "fixed" in the pores of natural manganese ore under natural conditions, thereby renewing the intact surface layer and forming a new ecological surface layer, thus improving the adsorption capacity of natural manganese at the interface.

[0048] 7. The iron-aluminum solution is mixed with iron-aluminum slag and manganese dioxide. After mixing, the pH is adjusted to 3.8 with dilute NaOH solution to further precipitate iron and aluminum ions, generating FeOOH and AlOOH, which are attached to the surface of iron-aluminum slag and pyrolusite, to obtain a mixture of iron-aluminum slag and manganese dioxide.

[0049] 8. Mix the iron-aluminum slag manganese dioxide mixture with charcoal powder at a mass ratio of 2:1 to form a slurry, add it to a mold to form a blank; shape it into a columnar material.

[0050] 9. After shaping, allow the material to air dry naturally. Place the columnar material in the environment to air dry naturally for 8 hours. Natural air drying makes it easier to transfer and collect.

[0051] 10. Place the air-dried columnar material into an oven and dry it at 100℃ for 30 minutes; the temperature of 100℃ is mainly to evaporate the free water.

[0052] 11. Sintering: After drying, place the product in a tube furnace and calcine at 100°C for 1 hour under N2 protection; the high-temperature calcination gives it good mechanical strength, which is beneficial for recycling.

[0053] Example 2

[0054] This disclosure provides a method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite, including the following steps:

[0055] 1. In the lithium-ion battery recycling process, the iron and aluminum slag obtained from the wet leaching process is dried, crushed and ground. The grinding mill speed is 250 r / min, the grinding time is 45 min, and the volume ratio of grinding balls to raw materials is 4:1. The fine iron and aluminum slag product is screened to 70 mesh.

[0056] 2. Aluminate coupling agents are used to modify iron-aluminum slag, giving the iron-aluminum slag structure more active sites and stronger heavy metal binding. At the same time, acid activation is used before modifying the iron-aluminum slag with aluminate coupling agents to remove organic matter and other impurities in the iron-aluminum slag, clear the pores, and improve the specific surface area and surface activity of the iron-aluminum slag.

[0057] 3. Pyrolusite is generally associated with oxides such as Al and Fe2O3. Pyrolusite can be subjected to preliminary sulfation treatment by using a 200g / L sulfuric acid solution to dissolve Fe and Al.

[0058] 4. The solution of H2SO4 treated with pyrolusite was subjected to solid-liquid separation and dried at 70℃ for 180 min to obtain relatively pure dry MnO2 solid.

[0059] 5. Oxalic acid is a highly efficient chelating agent. It can form complexes and strongly adsorb on the surface of MnO2. Adding 0.7 mol / L oxalic acid solution dissolves the surface of MnO2. Combined with the oxidizing properties of 0.2 mol / L KMnO4, the surface properties are improved to enhance its surface adsorption capacity.

[0060] 6. The leaching effect of 70g / L dilute sulfuric acid and the reducing dissolution effect of 15g / L hydrazine hydrate work synergistically to dissolve the impurities that are "fixed" in the pores of natural manganese ore under natural conditions, thereby renewing the intact surface layer and forming a new ecological surface layer, thus improving the adsorption capacity of natural manganese at the interface.

[0061] 7. The iron-aluminum solution is mixed with iron-aluminum slag and manganese dioxide. After mixing, the pH is adjusted to 4.0 with dilute NaOH solution to further precipitate iron and aluminum ions, generating FeOOH and AlOOH, which are attached to the surface of iron-aluminum slag and pyrolusite, to obtain a mixture of iron-aluminum slag and manganese dioxide.

[0062] 8. Mix the iron-aluminum slag manganese dioxide mixture with charcoal powder at a mass ratio of 2.5:1 to form a slurry, add it to a mold to form a blank; shape it into a columnar material.

[0063] 9. After shaping, allow the material to air dry naturally. Place the columnar material in the environment to air dry naturally for 10 hours. Natural air drying facilitates transfer and collection.

[0064] 10. Place the air-dried columnar material into an oven and dry it at 105℃ for 45 minutes; the temperature of 105℃ is mainly to evaporate the free water.

[0065] 11. Sintering: After drying, place the product in a tube furnace and calcine at 150°C for 2 hours under N2 protection; the high-temperature calcination gives it good mechanical strength, which is beneficial for recycling.

[0066] Example 3

[0067] This disclosure provides a method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite, including the following steps:

[0068] 1. In the lithium-ion battery recycling process, the iron and aluminum slag obtained from the wet leaching process is dried, crushed, and ground. The grinding mill speed is 300 r / min, the grinding time is 60 min, and the volume ratio of grinding balls to raw materials is 5:1. The product is then screened to a fine iron and aluminum slag product of 60-80 mesh.

[0069] 2. Aluminate coupling agents are used to modify iron-aluminum slag, giving the iron-aluminum slag structure more active sites and stronger heavy metal binding. At the same time, acid activation is used before modifying the iron-aluminum slag with aluminate coupling agents to remove organic matter and other impurities in the iron-aluminum slag, clear the pores, and improve the specific surface area and surface activity of the iron-aluminum slag.

[0070] 3. Pyrolusite is generally associated with oxides such as Al and Fe2O3. Pyrolusite can be subjected to preliminary sulfation treatment by using a 300g / L sulfuric acid solution to dissolve Fe and Al.

[0071] 4. The solution of H2SO4 treated with pyrolusite was subjected to solid-liquid separation and dried at 80℃ for 240 min to obtain relatively pure dry MnO2 solid.

[0072] 5. Salicylic acid is a highly efficient chelating agent that can form complexes and strongly adsorb on the surface of MnO2. Adding 1 mol / L salicylic acid solution causes the surface to dissolve, and the oxidizing properties of 0.3 mol / L KMnO4 are combined to improve the surface properties and enhance its surface adsorption capacity.

[0073] 6. The leaching effect of 80g / L dilute sulfuric acid and the reducing dissolution effect of 20g / L hydrazine hydrate work synergistically to dissolve the impurities that are "fixed" in the pores of natural manganese ore under natural conditions, thereby renewing the intact surface layer and forming a new ecological surface layer, thus improving the adsorption capacity of natural manganese at the interface.

[0074] 7. The iron-aluminum solution is mixed with iron-aluminum slag and manganese dioxide. After mixing, the pH is adjusted to 4.5 with dilute NaOH solution to further precipitate iron-aluminum ions, generating FeOOH and AlOOH, which are attached to the surface of iron-aluminum slag and pyrolusite, to obtain a mixture of iron-aluminum slag and manganese dioxide.

[0075] 8. Mix the iron-aluminum slag manganese dioxide mixture with charcoal powder at a mass ratio of 3:1 to form a slurry, add it to a mold to form a blank; shape it into a columnar material.

[0076] 9. After shaping, allow the material to air dry naturally. Place the columnar material in the environment to air dry naturally for 12 hours. Natural air drying makes it easier to transfer and collect.

[0077] 10. Place the air-dried columnar material into an oven and dry it at 110℃ for 60 minutes; the temperature of 110℃ is mainly to evaporate the free water.

[0078] 11. Sintering: After drying, place the product in a tube furnace and calcine at 200℃ for 3 hours under N2 protection; the high-temperature calcination gives it good mechanical strength, which is conducive to recycling.

[0079] Example 4

[0080] This disclosure provides a method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite, including the following steps:

[0081] 1. In the lithium-ion battery recycling process, the iron and aluminum slag obtained from the wet leaching process is dried, crushed, and ground. The grinding mill speed is 200 r / min, the grinding time is 30 min, and the volume ratio of grinding balls to raw materials is 3:1. The product is then screened to a fine iron and aluminum slag product of 60-80 mesh.

[0082] 2. Aluminate coupling agents are used to modify iron-aluminum slag, giving the iron-aluminum slag structure more active sites and stronger heavy metal binding. At the same time, acid activation is used before modifying the iron-aluminum slag with aluminate coupling agents to remove organic matter and other impurities in the iron-aluminum slag, clear the pores, and improve the specific surface area and surface activity of the iron-aluminum slag.

[0083] 3. Pyrolusite is generally associated with oxides such as Al and Fe2O3. Pyrolusite can be subjected to preliminary sulfation treatment by using a 100g / L sulfuric acid solution to dissolve Fe and Al.

[0084] 4. The solution of H2SO4 treated with pyrolusite was subjected to solid-liquid separation and dried at 60℃ for 120 min to obtain relatively pure dry MnO2 solid.

[0085] 5. Citric acid and tartaric acid are highly efficient chelating agents. They can form complexes and strongly adsorb on the surface of MnO2. Adding a 1 mol / L mixed solution of citric acid and tartaric acid will dissolve the surface. Combined with the oxidizing properties of 0.1 mol / L KMnO4, the surface properties are improved to enhance its surface adsorption capacity.

[0086] 6. The leaching effect of 60g / L dilute sulfuric acid and the reducing dissolution effect of 10g / L hydrazine hydrate work synergistically to dissolve the impurities that are "fixed" in the pores of natural manganese ore under natural conditions, thereby renewing the intact surface layer and forming a new ecological surface layer, thus improving the adsorption capacity of natural manganese at the interface.

[0087] 7. The iron-aluminum solution is mixed with iron-aluminum slag and manganese dioxide. After mixing, the pH is adjusted to 3.8-4.2 with dilute NaOH solution to further precipitate iron and aluminum ions, generating FeOOH and AlOOH, which are attached to the surface of iron-aluminum slag and pyrolusite, to obtain a mixture of iron-aluminum slag and manganese dioxide.

[0088] 8. Mix the iron-aluminum slag manganese dioxide mixture with charcoal powder at a mass ratio of 2:1 to form a slurry, add it to a mold to form a blank; shape it into a columnar material.

[0089] 9. After shaping, allow the material to air dry naturally. Place the columnar material in the environment to air dry naturally for 8 hours. Natural air drying makes it easier to transfer and collect.

[0090] 10. Place the air-dried columnar material into an oven and dry it at 100℃ for 30 minutes; the temperature of 100℃ is mainly to evaporate the free water.

[0091] 11. Sintering: After drying, place the product in a tube furnace and calcine at 100°C for 1 hour under N2 protection; the high-temperature calcination gives it good mechanical strength, which is beneficial for recycling.

Claims

1. A method for preparing a phosphorus removal agent by mixing waste battery recycled iron-aluminum slag with pyrolusite, comprising the following steps: The iron-aluminum slag obtained from the grinding and crushing process of waste battery recycling is used to obtain fine iron-aluminum slag. The fine iron-aluminum slag was activated with acid, and then modified with an aluminate coupling agent to obtain modified iron-aluminum slag. The pyrolusite was crushed, acid-leached, and filtered to obtain solid MnO2 and a solution containing Fe and Al. Iron powder was added to the Fe and Al solution to obtain a Fe(II) and Al solution; The modified MnO2 solid was first reacted with a chelating agent and a KMnO4 solution, and then with a dilute sulfuric acid solution and hydrazine hydrate. After filtration, the modified MnO2 solid was obtained. The modified iron-aluminum slag, modified MnO2 solid, Fe(II) and Al solution are mixed, and then NaOH solution is added to adjust the pH to 3.8-4.

5. At the same time, air is introduced to obtain an iron-aluminum slag-manganese dioxide mixture. Subsequently, the mixture is formed into a blank and sintered to obtain a phosphorus removal adsorbent.

2. The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in claim 1, characterized in that, The blanking process requires the addition of charcoal powder. The iron-aluminum slag manganese dioxide mixture is mixed with the charcoal powder at a mass ratio of 2~3:1 to form a slurry. The slurry is then added to a mold to obtain the molding material.

3. The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in claim 2, characterized in that, The charcoal powder includes activated carbon.

4. The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in claim 1, characterized in that, The chelating agent is one or more of citric acid, oxalic acid, salicylic acid, and tartaric acid, with a concentration of 0.5~1 mol / L; the KMnO4 solution has a concentration of 0.1~0.3 mol / L; the dilute sulfuric acid solution has a concentration of 60~80 g / L; and the hydrazine hydrate has a concentration of 10~20 g / L.

5. The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in claim 1, characterized in that, The acid leaching solution is a sulfuric acid solution of 100-300 g / L; the MnO2 solid obtained after filtration needs to be dried at 60-80℃ for 120-240 min.

6. The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in claim 1, characterized in that, The grinding and crushing process uses a sand mill. The rotation speed of the sand mill is 200~300 r / min, the grinding time is 30~60 min, and the volume ratio of grinding balls to raw materials is 3~5:

1. The particle size of the fine iron-aluminum slag is 60~80 mesh.

7. The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in claim 1, characterized in that, The sintering process is carried out under an inert atmosphere, with a sintering temperature of 100℃~200℃ and a sintering time of 1~3h.

8. The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite as described in claim 1, characterized in that, After the blank is formed but before sintering, it also includes air drying, which is to place it in the environment for natural air drying for 8-12 hours.

9. The method for preparing a phosphorus removal agent by mixing waste battery recycling iron-aluminum slag with pyrolusite according to claim 8, characterized in that, After air drying and before sintering, the process also includes drying, which is carried out in an oven at a temperature of 100-110℃ for 30-60 minutes.

Images