Adsorption material and preparation method thereof, method for removing calcium from manganese-containing solution and application

Abstract

The invention belongs to the technical field of impurity removal, and particularly relates to an adsorption material, a preparation method thereof, a method for removing calcium from a manganese-containing solution and application. The adsorption material comprises porous manganese dioxide, pores are at least distributed on the surface of the porous manganese dioxide, and the ratio of the pore diameter of the pores to the diameter of calcium ions is (1-1.5): 1. The adsorption material has excellent calcium ion adsorption performance, calcium ion impurities in the manganese-containing solution can be selectively and efficiently removed, the removal rate of main elements such as manganese is low, the calcium-removed manganese-containing solution with high purity and high concentration can be obtained easily, and the problems that in the manganese resource extraction process, the impurity calcium is not completely removed, and the extraction efficiency is low can be successfully solved. Equipment corrosion caused by calcium removal of phosphogypsum and traditional fluoride is avoided. Moreover, after the adsorption material adsorbs the calcium ions, the adsorbed calcium ions can be removed through elution and other treatment modes, so that the adsorption material can be recycled and reused, and is green, environment-friendly and high in economic benefit.

Description

Technical Field

[0001] The present application belongs to the technical field of impurity removal, and in particular relates to an adsorption material and a preparation method thereof, and a method and application of removing calcium from a manganese-containing solution. Background Art

[0002] With the rise of the new energy industry, the extraction and utilization of manganese resources has become more strategically significant. The global manganese ore resources are relatively abundant, but unevenly distributed. China's manganese resources rank about sixth in the world, mainly distributed in Guangxi, Hunan and Yunnan. Manganese ore mainly exists in the form of rhodochrosite (MnCO3) and pyrolusite (MnO2). Due to the depletion of rhodochrosite resources and the high content of alkaline earth impurities such as aluminum, calcium, potassium and sodium, the extraction of manganese resources from pyrolusite has attracted more and more market attention.

[0003] Traditional leaching of pyrolusite is mainly based on reduction leaching. In recent years, as the country has been controlling environmental protection and energy consumption, tail gas reduction leaching has become a new solution for leaching pyrolusite and has attracted much attention from the market. Traditional reducing gases on the market include sulfur dioxide, nitrogen oxides, etc. Since the use of sulfur dioxide gas will produce a large amount of difficult-to-handle phosphogypsum problems, using nitrogen oxides as reducing gases has more process advantages. Using nitrogen oxides as reducing gases, the calcium resources in pyrolusite enter the manganese solution as soluble calcium nitrate. Traditional methods for decalcification include freezing, precipitation, ion exchange, adsorption, etc. Among them, extraction and ion exchange methods require large amounts of resin and extractant, high regeneration costs, and low ion selectivity. Precipitation method requires more precipitants, which is easy to cause equipment corrosion. Other methods such as electrodialysis, cooling crystallization, concentration purification, etc. currently have certain limitations, such as high production costs, complex purification processes, and serious environmental pollution, which are difficult to meet industrial requirements.

[0004] Therefore, there is an urgent need to develop a method for decalcifying manganese ore leaching solution to achieve the effect of selective decalcification. Summary of the invention

[0005] The purpose of the present application is to provide an adsorption material and a preparation method thereof, a method for removing calcium from a manganese-containing solution and an application thereof, aiming to solve the problem that calcium ions in a manganese-containing solution are difficult to selectively remove to a certain extent.

[0006] In order to achieve the above application purpose, the technical solution adopted in this application is as follows:

[0007] In a first aspect, the present application provides an adsorption material, which includes porous manganese dioxide, wherein pores are distributed at least on the surface of the porous manganese dioxide, and the ratio of the pore diameter to the diameter of the calcium ion is (1-1.5):1.

[0008] In some possible implementations, the diameter of the pore is 0.2 nm to 0.3 nm.

[0009] In some possible implementations, the particle size of the porous manganese dioxide is 2200 nm to 5000 nm.

[0010] In some possible implementations, the specific surface area of ​​the porous manganese dioxide is 200 m 2 / g~330m 2 / g.

[0011] In some possible implementations, the pore volume of the porous manganese dioxide is 0.1 cm 3 / g~0.8cm 3 / g.

[0012] In some possible implementations, the porosity of the porous manganese dioxide is 30% to 95%.

[0013] In a second aspect, the present application provides a method for preparing an adsorbent material, comprising the following steps:

[0014] Dissolving a soluble manganese source, an oxidant and a soluble calcium salt into a solution for mixed reaction to obtain manganese dioxide adsorbing calcium ions;

[0015] The calcium ions in the manganese dioxide adsorbing calcium ions are eluted and removed to obtain porous manganese dioxide.

[0016] In some possible implementations, the mixing reaction step includes: preparing the calcium salt into a calcium salt solution, and sequentially adding the manganese source and the oxidant to react.

[0017] In some possible implementations, the molar ratio of the calcium element in the calcium salt, the manganese element in the manganese source, and the oxidant is (1-2.2):1:(1.5-5).

[0018] In some possible implementations, the step of eluting and removing calcium ions includes: eluting the manganese dioxide adsorbing calcium ions with a solvent, and then separating the solid and liquid.

[0019] In some possible implementations, the calcium salt includes at least one of calcium chloride, calcium gluconate, calcium dihydrogen phosphate, calcium nitrate, calcium bicarbonate, calcium bisulfate, calcium bisulfite, calcium hypochlorite, calcium bromide, calcium iodide, calcium chlorate, calcium perchlorate, and calcium permanganate.

[0020] In some possible implementations, the manganese source includes at least one of manganese sulfate, manganese chloride, manganese nitrate, potassium permanganate, manganese acetate, and manganese dihydrogen phosphate.

[0021] In some possible implementations, the oxidant includes at least one of hydrogen peroxide, potassium permanganate, nitric acid, oxygen and ozone.

[0022] In some possible implementations, the solvent used for eluting and removing calcium ions includes at least one of water, dilute nitric acid, ethanol, acetic acid, dilute hydrochloric acid, dilute sulfuric acid, and methanol.

[0023] In some possible implementations, the mass concentration of the calcium salt solution is 5% to 15%.

[0024] In a third aspect, the present application provides a method for removing calcium from a manganese-containing solution, comprising the following steps:

[0025] obtaining a manganese-containing solution, wherein the manganese-containing solution contains calcium ions;

[0026] The above-mentioned adsorption material and / or the adsorption material prepared by the above-mentioned method is mixed with the manganese-containing solution for adsorption treatment to obtain a calcium-removed manganese-containing solution.

[0027] In some possible implementations, the mass ratio of the adsorption material to the manganese-containing solution is (1% to 3%):1.

[0028] In some possible implementations, the manganese-containing solution includes a manganese ore leaching solution, and the preparation of the manganese ore leaching solution includes the steps of: mixing manganese ore with an acid hydrolysis solution to obtain the manganese ore leaching solution.

[0029] In some possible implementations, the molar ratio of the manganese element in the manganese ore to the acid hydrolysis solution is 1:(1-3).

[0030] In some possible implementations, the acidolysis solution includes at least one of nitric acid, hydrochloric acid, sulfuric acid, water and nitrogen oxides, and water and sulfur dioxide.

[0031] In some possible implementations, the manganese ore includes at least one of rhodochrosite and pyrolusite.

[0032] In a fourth aspect, the present application provides a method for preparing a manganese-containing positive electrode material, wherein the manganese source for preparing the manganese-containing positive electrode material is a decalcified manganese-containing solution prepared by the above-mentioned method for decalcifying a manganese-containing solution.

[0033] The adsorption material provided in the first aspect of the present application includes porous manganese dioxide, and the surface of the porous manganese dioxide has pores whose pore diameters match the diameters of calcium ions. The difference between the diameters of calcium ions and other ions can be used to form specific targeted adsorption of calcium ions. Therefore, the adsorption material of the present application has excellent calcium ion adsorption performance, and is applied to the decalcification of manganese-containing solutions, and can selectively and efficiently remove calcium ion impurities in manganese-containing solutions, while the removal rate of main elements such as manganese is low.

[0034] The second aspect of the present application is a method for preparing an adsorbent material, wherein a soluble manganese source and an oxidant are used as raw materials to prepare manganese dioxide, and at the same time, calcium ions are introduced at the raw material end, so that calcium ions are uniformly adsorbed in situ in manganese dioxide; after the calcium ions in the manganese dioxide adsorbing calcium ions are eluted and removed, pores adapted to the size of calcium ions are formed in situ in manganese dioxide, and the difference between the particle size of calcium ions and other ions is utilized to form specific targeted adsorption of calcium ions. In the process of synthesizing the adsorbent material, the present application forms pores in situ according to the radius of the impurity element ions, and the prepared adsorbent material is based on porous manganese dioxide, and has pores adapted to the size of calcium ions on the surface of the porous manganese dioxide, so as to form targeted adsorption of calcium ions. The process is simple and suitable for large-scale industrial production and application. The prepared adsorbent material has excellent calcium ion adsorption performance, and is applied to the decalcification of manganese-containing solutions, and can selectively and efficiently remove calcium ion impurities in manganese-containing solutions, and the removal rate of main elements such as manganese is low.

[0035] The third aspect of the present application is a method for decalcifying a manganese-containing solution. After obtaining the manganese-containing solution, the above-mentioned adsorption material is used to perform mixed adsorption treatment on the manganese-containing solution. Since the above-mentioned adsorption material includes porous manganese dioxide, the adsorption material has pores that are adapted to the size of calcium ions, and can form specific targeted adsorption for calcium ions. Therefore, calcium ion impurities in the manganese-containing solution can be selectively adsorbed and removed, and the removal rate of main elements such as manganese is low. It is conducive to obtaining a high-purity and high-concentration decalcified manganese-containing solution. The method for decalcifying a manganese-containing solution of the present application has the advantages of simple process, easy operation, strong pertinence, and good impurity removal effect. It can successfully solve the problems of incomplete removal of impurity calcium in the process of manganese resource extraction, equipment corrosion caused by phosphogypsum and traditional fluoride decalcification.

[0036] The fourth aspect of the present application is a method for preparing a manganese-containing positive electrode material, which uses the decalcified manganese-containing solution obtained by the above-mentioned method for decalcifying a manganese-containing solution as a manganese source, has a high degree of resource utilization, can reduce production costs, and has broad market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 It is a schematic diagram of the process of preparing the adsorption material provided in the embodiment of the present application;

[0039] Figure 2 It is a schematic flow chart of the method for decalcifying a manganese-containing solution provided in an embodiment of the present application. DETAILED DESCRIPTION

[0040] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0041] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0042] In this application, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b or c", or "at least one of a, b and c", can all represent: a, b, c, ab (i.e. a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0043] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0044] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0045] The weight of the relevant components mentioned in the embodiments of the present specification can not only refer to the specific content of each component, but also represent the proportional relationship between the weights of the components. Therefore, as long as the content of the relevant components in the embodiments of the present specification is proportionally enlarged or reduced, it is within the scope disclosed in the embodiments of the present specification. Specifically, the mass described in the embodiments of the present specification can be μg, mg, g, kg and other mass units known in the chemical industry.

[0046] The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and should not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX may also be referred to as the second XX, and similarly, the second XX may also be referred to as the first XX. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0047] A first aspect of an embodiment of the present application provides an adsorption material, which includes porous manganese dioxide. Pores are distributed on the surface of the porous manganese dioxide, and the ratio of the pore size to the diameter of the calcium ion is (1-1.5):1.

[0048] The adsorption material provided in the first aspect of the embodiment of the present application includes porous manganese dioxide, and the surface of the porous manganese dioxide has pores adapted to the diameter of calcium ions. The difference between the diameter of calcium ions and other ions can be used to form specific targeted adsorption of calcium ions. Therefore, the adsorption material of the embodiment of the present application has excellent calcium ion adsorption performance, can be used for calcium removal in manganese-containing solutions, and has a low removal rate for main elements such as manganese. In one embodiment, it can be applied to the decalcification of manganese ore leachate, and can selectively and efficiently remove calcium ion impurities in manganese ore leachate, and has a low removal rate for main elements such as manganese. It is conducive to obtaining high-purity and high-concentration calcium-removed manganese ore leachate, and can successfully solve the problems of incomplete removal of impurity calcium, phosphogypsum and equipment corrosion caused by traditional fluoride decalcification during manganese resource extraction. In addition, after the adsorption material is subjected to calcium ion adsorption, the adsorbed calcium ions can be removed by elution and other treatment methods, so that the adsorption material can be recycled and reused, which is green and environmentally friendly and has high economic benefits.

[0049] It should be noted that, in the above-mentioned embodiments of the present application, targeted adsorption refers to the process of making the target molecule (calcium ion) and the adsorbent material (porous manganese dioxide) surface tightly combined by specific interactions (such as electrostatic interaction, π-π interaction, van der Waals force and hydrogen bond, etc.). In porous manganese dioxide, due to the limitation of pore size and the optimization of surface properties, it is possible to achieve targeted adsorption specific to calcium ions. Specifically, the size of calcium ions matches the pore size of porous manganese dioxide to ensure that calcium ions can smoothly enter the pore interior and be adsorbed. In addition, there is a strong interaction between calcium ions and the porous manganese dioxide surface, which can ensure that calcium ions are not easy to fall off during adsorption. By optimizing the surface properties of porous manganese dioxide, it is possible to achieve selective adsorption specific to calcium ions, thereby avoiding the interference of other non-target molecules.

[0050] For example, the ratio of the pore size of the porous manganese dioxide to the diameter of the calcium ions can be any typical but non-limiting value such as 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, or an interval between any two values.

[0051] In some possible implementations, the diameter of the pores on the surface of porous manganese dioxide is 0.2nm to 0.4nm. In this case, the diameter of the pores in porous manganese dioxide is highly compatible with the particle size of calcium ions, which allows calcium ions to smoothly enter the pores and be adsorbed. This size matching is the basis of targeted adsorption, ensuring that only calcium ions of a specific size can be effectively captured. Exemplarily, the diameter of the pores in porous manganese dioxide can be 0.2nm, 0.22nm, 0.24nm, 0.26nm, 0.28nm, 0.30nm, 0.32nm, 0.34nm, 0.36nm, 0.38nm, 0.4nm, etc., typical but non-restrictive arbitrary point values ​​or interval values ​​between any two point values.

[0052] In some possible implementations, the particle size (average particle size) of porous manganese dioxide is 2200nm~5000nm. In this case, the particle size of porous manganese dioxide is small, the adsorption active surface area is large, and it is more conducive to targeted adsorption of calcium ions through surface pores. Exemplary, the particle size of porous manganese dioxide can be 2200nm, 2500nm, 3000nm, 3500nm, 4000nm, 4500nm, 5000nm, 4500nm, etc. typical but non-restrictive arbitrary point values ​​or interval values ​​between any two point values.

[0053] In some possible implementations, the specific surface area of ​​the porous manganese dioxide is 200 m 2 / g~330m 2 / g. In this case, the active specific surface area of ​​the porous manganese dioxide is large, ensuring that the adsorbent material has a high adsorption efficiency for calcium ions. Exemplarily, the specific surface area of ​​the porous manganese dioxide particles can be 200m 2 / g, 210m 2 / g, 220m 2 / g, 230m 2 / g, 240m 2 / g, 250m 2 / g, 260m 2 / g, 270m 2 / g, 280m 2 / g, 290m 2 / g、300m 2 / g, 310m 2 / g, 320m 2 / g, 330m2 / g and other typical but non-limiting arbitrary point values ​​or interval values ​​between any two point values.

[0054] In some possible implementations, the pore volume in the porous manganese dioxide is 0.1 cm 3 / g~0.8cm 3 / g. In this case, the pore volume of the porous manganese dioxide is high, indicating that the pore content is large and more calcium ions can be adsorbed, so the adsorbent material has a high adsorption efficiency for calcium ions. For example, the pore volume of the porous manganese dioxide particles can be 0.1cm 3 / g, 0.2cm 3 / g, 0.3cm 3 / g, 0.4cm 3 / g, 0.5cm 3 / g, 0.6cm 3 / g, 0.7cm 3 / g, 0.8cm 3 / g and other typical but non-limiting arbitrary point values ​​or interval values ​​between any two point values.

[0055] In some possible implementations, the porosity in the porous manganese dioxide is 30% to 95%. In this case, the porous manganese dioxide has a high porosity, so the adsorbent material has a high adsorption efficiency for calcium ions. Exemplarily, the porosity of the porous manganese dioxide particles can be 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, etc., which are typical but non-restrictive arbitrary point values ​​or interval values ​​between any two point values.

[0056] In a second aspect, the present invention provides a method for preparing an adsorbent material. Figure 1 As shown, the following steps are included:

[0057] S10. A soluble manganese source, an oxidant and a soluble calcium salt are mixed and reacted in a solution to obtain manganese dioxide that adsorbs calcium ions;

[0058] S20. eluting and removing the calcium ions from the manganese dioxide that has adsorbed calcium ions to obtain porous manganese dioxide.

[0059] The preparation method of the adsorbent material of the embodiment of the present application is to prepare manganese dioxide with a soluble manganese source and an oxidant as raw materials, and at the same time, calcium ions are introduced at the raw material end, so that calcium ions are uniformly adsorbed in situ in manganese dioxide; after the calcium ions in the manganese dioxide adsorbed with calcium ions are eluted and removed, pores adapted to the size of calcium ions are formed in situ in manganese dioxide, and the difference between the particle size of calcium ions and other ions can be used to form specific targeted adsorption of calcium ions. In the synthesis process of the adsorbent material, the embodiment of the present application forms pores in situ according to the radius of the impurity element ions. The prepared adsorbent material is based on porous manganese dioxide, and has pores adapted to the diameter of calcium ions on the surface of the porous manganese dioxide, forming targeted adsorption of calcium ions. The process is simple and suitable for large-scale industrial production and application. The prepared adsorbent material has excellent calcium ion adsorption performance, which is applied to calcium removal in manganese-containing solutions, such as calcium removal of manganese ore leachate, and can selectively and efficiently remove calcium ion impurities in manganese ore leachate, and the removal rate of main elements such as manganese is low.

[0060] In the above step S10: a soluble manganese source, an oxidant and a soluble calcium salt are mixed and reacted, wherein the manganese source provides a matrix for generating MnO2, the oxidant provides oxidation degree, and the calcium salt provides calcium ions, and in situ pores are formed according to the radius of the calcium ions during the synthesis of manganese dioxide.

[0061] In some possible implementations, the manganese source includes at least one of manganese sulfate, manganese chloride, manganese nitrate, potassium permanganate, manganese acetate, and manganese dihydrogen phosphate. These manganese sources have good solubility and are conducive to mixing reactions.

[0062] In some possible implementations, the calcium salt includes at least one of calcium chloride, calcium gluconate, calcium dihydrogen phosphate, calcium nitrate, calcium bicarbonate, calcium bisulfate, calcium bisulfite, calcium hypochlorite, calcium bromide, calcium iodide, calcium chlorate, calcium perchlorate, and calcium permanganate. These calcium salts all have good solubility and can be completely dissolved and ionized in a solvent to form uniform and stable calcium ions.

[0063] In some possible implementations, the oxidant includes at least one of hydrogen peroxide, potassium permanganate, nitric acid, oxygen and ozone. These oxidants all have high oxidizing properties and are conducive to mixed reactions.

[0064] In some possible implementations, the concentration of hydrogen peroxide is 15% to 30%. In this case, the concentration of hydrogen peroxide is conducive to a stable and efficient reaction rate between hydrogen peroxide and potassium permanganate, and avoids excessively high or low concentrations that affect the reaction rate and pore-forming effect.

[0065] Exemplarily, the concentration of hydrogen peroxide can be 15%, 16%, 18%, 20%, 22%, 25%, 28%, 30%, or any other typical but non-limiting value or an interval between any two values.

[0066] In some possible implementations, potassium permanganate, hydrogen peroxide and calcium nitrate salt are mixed and reacted in a solution, wherein potassium permanganate provides a matrix and oxidizability for generating MnO2, hydrogen peroxide provides oxidation degree, and calcium salt provides calcium ions, and in-situ pores are formed according to the radius of calcium ions during the synthesis of manganese dioxide. The reaction process of potassium permanganate and hydrogen peroxide is shown in the following equation:

[0067] 3H2O2+2KMnO4=2KOH+2MnO2↓+2H2O+3O2↑.

[0068] In some possible implementations, the step of the mixed reaction includes: dissolving the calcium salt in a solvent such as water to prepare a calcium salt solution, and then sequentially adding potassium permanganate and hydrogen peroxide to react. In this case, it is ensured that the calcium salt is fully and evenly dissolved in the reaction system, which is convenient for in-situ pore formation, and it is also beneficial to control the reaction rate of potassium permanganate and hydrogen peroxide, so as to avoid too fast a reaction, which makes it difficult for calcium ions to be uniformly and abundantly adsorbed into manganese dioxide.

[0069] In some possible implementations, the concentration of the calcium salt solution in the mixed reaction system is 5% to 15%. In this case, it is fully ensured that the calcium ions can be stably and evenly dispersed in the reaction system to avoid the calcium salt being not completely dissolved and ionized due to the high concentration; and it is fully ensured that there are enough calcium ions in the reaction system to form pores in situ according to the radius of the calcium ions during the synthesis of manganese dioxide, forming uniform and abundant pores in manganese dioxide that are adapted to the size of the calcium ions. This ensures the adsorption effect of the adsorbent material on calcium ions.

[0070] Exemplarily, in the mixed reaction system, the concentration of calcium salt can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, or any other typical but non-limiting point value or an interval value between any two points.

[0071] In some possible implementations, the molar ratio of calcium in the calcium salt, manganese in the manganese source, and the oxidant is (1-2.2):1:(1.5-5). In this case, the ratio of potassium permanganate and hydrogen peroxide fully ensures that the two react fully to form manganese dioxide, and the ratio of calcium salt ensures that pores are formed in situ according to the radius of calcium ions during the synthesis of manganese dioxide, forming uniformly distributed and abundant pores in manganese dioxide that are adapted to the size of calcium ions, without causing excessive waste of raw materials.

[0072] Illustratively, the molar ratio of calcium in the calcium salt, manganese in the manganese source and the oxidant can be 1:1:1.5, 1.5:1:1.5, 2:1:1.5, 2.2:1:1.5, 1:1:2, 1.5:1:2, 2:1:1.5, 2.2:1:2, 1:1:3, 1.5:1:3, 2:1:3, 2.2:1:3, 1:1:4, 1.5:1:4, 2:1:4, 2.2:1:4, 1:1:5, 1.5:1:5, 2:1:5, 2.2:1:5 and the like, and can be any typical but non-limiting point value or interval value between any two point values.

[0073] In the above step S20:

[0074] In some possible implementations, the step of removing calcium ions by eluting includes: eluting the manganese dioxide adsorbing calcium ions with a solvent, and performing solid-liquid separation. In this case, a large amount of solvent is used to perform multiple elutions on the manganese dioxide adsorbing calcium ions, followed by solid-liquid separation, and the calcium ions adsorbed in the manganese dioxide are removed by elution to obtain porous manganese dioxide.

[0075] In some possible implementations, the amount of solvent added is 10 to 20 times the amount of manganese dioxide that adsorbs calcium ions. In this case, it is ensured that the calcium ions adsorbed in the manganese dioxide are fully eluted.

[0076] For example, the amount of the solvent used as the eluent can be 10 times, 12 times, 15 times, 18 times, 20 times, or any other typical but non-limiting value or an interval value between any two values ​​of the manganese dioxide adsorbing calcium ions.

[0077] In some possible implementations, the solvent used for eluting and removing calcium ions includes at least one of water, dilute nitric acid, ethanol, acetic acid, dilute hydrochloric acid, dilute sulfuric acid, and methanol. These solvents are all used as eluents and can elute and separate calcium ions from manganese dioxide that adsorbs calcium ions.

[0078] In some possible implementations, the concentration of dilute nitric acid is 1% to 5%. In other possible implementations, the concentration of dilute hydrochloric acid is 1% to 3%. In other possible implementations, the concentration of dilute sulfuric acid is 1% to 3%.

[0079] In a third aspect, the present invention provides a method for removing calcium from a manganese-containing solution, such as Figure 2 As shown, the following steps are included:

[0080] S30. Obtaining a manganese-containing solution, wherein the manganese-containing solution contains calcium ions;

[0081] S40. Mix the above-mentioned adsorption material and / or the adsorption material prepared by the above-mentioned method with the manganese-containing solution for adsorption treatment to obtain a calcium-removed manganese-containing solution.

[0082] The method for decalcifying a manganese-containing solution in an embodiment of the present application is, after obtaining the manganese-containing solution, the manganese-containing solution is subjected to mixed adsorption treatment using the above-mentioned adsorption material. Since the above-mentioned adsorption material includes porous manganese dioxide, the adsorption material has pores that are adapted to the size of calcium ions, and can form specific targeted adsorption for calcium ions. Therefore, calcium ion impurities in the manganese-containing solution can be selectively adsorbed and removed, and the removal rate of main elements such as manganese is low. It is conducive to obtaining a high-purity and high-concentration decalcified manganese-containing solution. The method for decalcifying a manganese-containing solution in an embodiment of the present application has the advantages of simple process, easy operation, strong pertinence, and good impurity removal effect. It can successfully solve the problems of incomplete removal of impurity calcium in the process of manganese resource extraction, equipment corrosion caused by phosphogypsum and traditional fluoride decalcification, etc.

[0083] In the above step S30:

[0084] In some possible implementations, the manganese-containing solution includes a manganese ore leachate, and the preparation of the manganese ore leachate includes the steps of: mixing the manganese ore with an acid solution and then treating it to obtain a manganese ore leachate. The manganese ore is treated with an acid solution to extract the manganese element and the like. However, because the acid solution is used as a reducing substance, the calcium resources in the manganese ore enter the manganese solution in the form of calcium ions, and thus the manganese ore leachate obtained by leaching often contains a higher concentration of calcium ions. The selective removal of calcium ions in the manganese ore leachate is crucial.

[0085] In some possible implementations, the manganese ore includes at least one of rhodochrosite (MnCO3) and pyrolusite (MnO2).

[0086] In some possible implementations, methods for obtaining manganese-containing solutions include nitric acid method, sulfuric acid method, hydrochloric acid method, and reduction leaching method, etc. Different leaching schemes can be selected according to the manganese ore raw materials.

[0087] In some possible implementations, the molar ratio of manganese in manganese ore to acid solution is 1:(1-3); under this ratio, the leaching effect of acid solution on manganese in manganese ore can be fully ensured. Exemplarily, the molar ratio of manganese in manganese ore to acid solution can be 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, 1:2.2, 1:2.5, 1:2.8, 1:3, etc., typical but non-limiting arbitrary point values ​​or interval values ​​between any two point values.

[0088] In some possible implementations, the acidolysis solution includes at least one of nitric acid, hydrochloric acid, sulfuric acid, water and nitrogen oxides, and water and sulfur dioxide. Among them, water and nitrogen oxides refer to water and nitrogen oxides mixed as an acidolysis solution; water and sulfur dioxide refer to water and sulfur dioxide mixed as an acidolysis solution. The concentration of nitric acid is 35% to 45%; the concentration of hydrochloric acid is 20% to 35%; and the concentration of sulfuric acid is 40% to 60%. In some possible implementations, rhodochrosite is mixed with nitric acid for treatment.

[0089] This concentration range ensures both the leaching efficiency of manganese in manganese ore and the safety of the reaction.

[0090] In some embodiments, pyrolusite is mixed with water and nitrogen oxides.

[0091] In the above step S40:

[0092] In some possible implementations, the temperature condition of the mixed adsorption treatment is 25°C to 65°C, and the duration is 2 to 6 hours. In this case, the mixed adsorption treatment of the adsorbent material and the manganese-containing solution is carried out, and the temperature is appropriately increased to increase the molecular motion, which can increase the probability of ion collision and improve the adsorption efficiency of the adsorbent material on calcium ions in the manganese-containing solution.

[0093] Exemplarily, the temperature of the mixed adsorption treatment can be 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, etc., any typical but non-limiting point value or an interval value between any two point values, and the duration can be 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, etc., any typical but non-limiting point value or an interval value between any two point values.

[0094] In some possible implementations, the weight ratio of the adsorption material to the manganese-containing solution is (1% to 3%): 1. In this case, the adsorption efficiency of the adsorption material on calcium ions in the manganese-containing solution can be fully ensured, while avoiding waste of resources and saving costs.

[0095] For example, the weight ratio of the adsorbent material to the manganese-containing solution may be 1%:1, 2%:1, 3%:1, or any other typical but non-limiting value or an interval value between any two values.

[0096] In some possible implementations, the method for removing calcium from a manganese-containing solution has a removal rate of no less than 96% for calcium ions in the manganese-containing solution and a removal rate of no more than 2% for manganese ions. The method for removing calcium from a manganese-containing solution in an embodiment of the present application has a high removal rate for calcium ions in the manganese-containing solution and a low removal rate for manganese ions, and can selectively adsorb and remove calcium ions without affecting the content of main elements such as manganese ions.

[0097] In a fourth aspect, an embodiment of the present application provides a method for preparing a manganese-containing positive electrode material, wherein the manganese source for preparing the manganese-containing positive electrode material is a decalcified manganese-containing solution prepared by the above-mentioned method for decalcifying a manganese-containing solution.

[0098] The method for preparing the manganese-containing positive electrode material in the embodiment of the present application adopts a decalcified manganese-containing solution prepared by a method for decalcifying a manganese-containing solution as a manganese source, has a high degree of resource utilization, can reduce production costs, and has broad market application prospects.

[0099] In order to enable the above-mentioned implementation details and operations of the present application to be clearly understood by those skilled in the art, as well as to demonstrate the significant improvement in the performance of the adsorption materials and preparation methods thereof, the method for removing calcium from manganese-containing solutions and their applications in the embodiments of the present application, the above-mentioned technical scheme is illustrated by means of multiple embodiments below.

[0100] Example 1

[0101] A porous manganese dioxide adsorption material with a particle size of 3000nm, a pore size of 0.2nm, and a specific surface area of ​​210m 2 / g, pore volume 0.15cm 3 / g, and the porosity is 70%.

[0102] The preparation method comprises the following steps: taking 11.4g potassium permanganate, soaking it in 300g 15% calcium nitrate solution, adding 12.89g hydrogen peroxide to carry out mixed reaction; then, adding the reaction product obtained by filtration into 12g water to carry out stirring elution treatment, and after eluting twice, a porous manganese dioxide adsorption material is obtained.

[0103] A method for decalcifying a manganese ore leaching solution comprises the following steps:

[0104] 1. Put 100g of pyrolusite into 300g of water, stir evenly, slowly introduce a nitrogen oxide mixture (including NO, NO2, NO4), react fully, and the pH value of the reaction solution is 0.1-0.5. Filter to obtain a manganese nitrate solution, i.e., a manganese ore leaching solution. The contents of metal elements in the pyrolusite and manganese nitrate solution before and after the pyrolusite is leached with nitrogen oxides are shown in Table 1 below.

[0105] 2. Take 6 g of the porous manganese dioxide adsorption material prepared in Example 1, put it into the manganese nitrate solution in step 1, react at room temperature (25° C.) for 2 hours, filter, and obtain a decalcified manganese nitrate solution. The content of metal elements in the decalcified manganese nitrate solution is shown in Table 1 below.

[0106] Table 1

[0107]

[0108] Example 2

[0109] A porous manganese dioxide adsorption material with a particle size of 2800nm, a pore size of 0.21nm, and a specific surface area of ​​262m 2 / g, pore volume 0.20cm 3 / g, and the porosity is 80%.

[0110] The preparation method comprises the following steps: taking 13.30 g potassium permanganate, soaking it in 300 g 25% calcium nitrate solution, adding 15.05 g hydrogen peroxide for mixed reaction; then, adding the reaction product obtained by filtration into 14 g ethanol for stirring and eluting treatment, and after eluting twice, a porous manganese dioxide adsorption material is obtained.

[0111] A method for decalcifying a manganese ore leaching solution comprises the following steps:

[0112] 1. Put 100g of pyrolusite into 300g of water, stir evenly, slowly introduce a nitrogen oxide mixture (including NO, NO2, NO4), react fully, and the pH value of the reaction solution is 0.1-0.5. Filter to obtain a manganese nitrate solution, i.e., a manganese ore leaching solution. The contents of metal elements in the pyrolusite and manganese nitrate solution before and after the pyrolusite is leached with nitrogen oxides are shown in Table 2 below.

[0113] 2. Take 7g of the porous manganese dioxide adsorption material prepared in Example 1, put it into the manganese nitrate solution in step 1, react at room temperature (25°C) for 3h, filter, and obtain decalcified manganese nitrate solution. The content of metal elements in the decalcified manganese nitrate solution is shown in Table 2 below.

[0114] Table 2

[0115]

[0116] Example 3

[0117] A porous manganese dioxide adsorption material, the particle size of which is 2500nm, the pore size is 0.20nm, and the specific surface area is 300m 2 / g, pore volume 0.30cm 3 / g, and the porosity is 90%.

[0118] The preparation method comprises the following steps: taking 15.2g potassium permanganate, soaking it in 300g 30% concentration calcium nitrate solution, adding 17.2g hydrogen peroxide to carry out mixed reaction; then, adding the reaction product obtained by filtration into 20g methanol to carry out stirring elution treatment, and after eluting twice, a porous manganese dioxide adsorption material is obtained.

[0119] A method for decalcifying a manganese ore leaching solution comprises the following steps:

[0120] 1. Put 100g of pyrolusite into 300g of water, stir evenly, slowly introduce a nitrogen oxide mixture (including NO, NO2, NO4), react fully, and the pH value of the reaction solution is 0.1-0.5. Filter to obtain a manganese nitrate solution, i.e., a manganese ore leaching solution. The contents of metal elements in the pyrolusite and manganese nitrate solution before and after the pyrolusite is leached with nitrogen oxides are shown in Table 3 below.

[0121] 2. Take 8g of the porous manganese dioxide adsorption material prepared in Example 1, put it into the manganese nitrate solution in step 1, react at room temperature (25°C) for 4h, filter, and obtain decalcified manganese nitrate solution. The content of metal elements in the decalcified manganese nitrate solution is shown in Table 3 below.

[0122] Table 3

[0123]

[0124] Example 4-Example 8

[0125] Examples 4 to 8 of the present application explored the effects of different adsorption temperatures, as shown in Table 4 below. Other relevant materials and preparation processes are referenced to Example 1.

[0126] Table 4

[0127]

[0128] From the test results in Table 4 above, it can be seen that the adsorption temperature between 45°C and 65°C shows better removal effect.

[0129] Example 9

[0130] A porous manganese dioxide adsorption material, the particle size of which is 2500nm, the pore size is 0.20nm, and the specific surface area is 300m 2 / g, pore volume 0.30cm 3 / g, and the porosity is 90%.

[0131] The preparation method comprises the following steps: taking 15.2g potassium permanganate, soaking it in 300g 30% concentration calcium nitrate solution, adding 17.2g hydrogen peroxide to carry out mixed reaction; then, adding the reaction product obtained by filtration into 20g methanol to carry out stirring elution treatment, and after eluting twice, a porous manganese dioxide adsorption material is obtained.

[0132] A method for decalcifying a manganese ore leaching solution comprises the following steps:

[0133] 1. Put 100g of pyrolusite into 300g of water, stir evenly, slowly introduce SO2, fully react, the pH value of the reaction solution is 0.1-0.5, filter to obtain manganese sulfate solution, i.e. manganese ore leaching solution. The contents of metal elements in pyrolusite and manganese sulfate solution before and after SO2 leaching of pyrolusite are shown in Table 5 below.

[0134] 2. Take 8g of the porous manganese dioxide adsorption material prepared in Example 5, put it into the manganese sulfate solution in step 1, react at room temperature (25°C) for 4h, filter, and obtain the decalcified manganese sulfate solution. The content of metal elements in the decalcified manganese sulfate solution is shown in Table 5 below.

[0135] Table 5

[0136]

[0137] Example 10

[0138] Example 10 explores the relationship between the amount of the solvent of the eluent and the manganese dioxide for adsorbing calcium ions, as shown in Table 6 below. Other related materials and preparation processes are referred to Example 1.

[0139] Table 6

[0140]

[0141]

[0142] It can be seen from the test results in Table 6 above that when the amount of the solvent used as the eluent is 10 to 20 times that of the manganese dioxide that adsorbs calcium ions, a better elution effect is achieved on the calcium ions adsorbed in the manganese dioxide.

[0143] Comparative Example 1

[0144] A method for decalcifying a manganese ore leaching solution comprises the following steps:

[0145] 1. Add 100g of pyrolusite to 300g of water, stir evenly, slowly introduce a nitrogen oxide mixture (including NO, NO2, NO4), react fully, and the pH value of the reaction solution is 0.1-0.5. Filter to obtain a manganese nitrate solution, i.e., a manganese ore leaching solution. The contents of metal elements in the pyrolusite and manganese nitrate solution before and after the pyrolusite is leached with nitrogen oxides are shown in Table 7 below.

[0146] 2. Take 6 g of 98% sulfuric acid and add it to the manganese nitrate solution in step 1. React at room temperature for 2 hours and filter to obtain decalcified manganese nitrate solution. The content of metal elements in the decalcified manganese nitrate solution is shown in Table 7 below.

[0147] Table 7

[0148]

[0149] Comparative Example 2

[0150] A method for decalcifying a manganese ore leaching solution comprises the following steps:

[0151] 1. Add 100g of pyrolusite to 300g of water, stir evenly, slowly introduce a nitrogen oxide mixture (including NO, NO2, NO4), react fully, and the pH value of the reaction solution is 0.1-0.5. Filter to obtain a manganese nitrate solution, i.e., a manganese ore leaching solution. The contents of metal elements in the pyrolusite and manganese nitrate solution before and after the pyrolusite is leached with nitrogen oxides are shown in Table 8 below.

[0152] 2. Take 6 g of ammonium fluoride with a mass fraction of 96%, put it into the manganese nitrate solution in step 1, react at room temperature for 2 hours, filter, and obtain a decalcified manganese nitrate solution. The content of metal elements in the decalcified manganese nitrate solution is shown in Table 8 below.

[0153] Table 8

[0154]

[0155] Comparative Example 3

[0156] A method for decalcifying a manganese ore leaching solution comprises the following steps:

[0157] 1. Add 100g of pyrolusite to 300g of water, stir evenly, slowly introduce a nitrogen oxide mixture (including NO, NO2, NO4), react fully, and filter to obtain a manganese nitrate solution, i.e., a manganese ore leaching solution, after the reaction liquid pH value is 0.1-0.5. The contents of metal elements in the pyrolusite and manganese nitrate solution before and after the pyrolusite is leached with nitrogen oxides are shown in Table 9 below.

[0158] 2. Take 6g of conventional manganese dioxide adsorption material, put it into the manganese nitrate solution in step 1, react at room temperature for 2h, filter, and obtain decalcified manganese nitrate solution. The content of metal elements in the decalcified manganese nitrate solution is shown in Table 9 below.

[0159] Table 9

[0160]

[0161] From the test results of the above embodiments and comparative examples, it can be seen that the embodiment of the present application adopts a porous manganese dioxide adsorption material with pores of the size adapted to calcium ions, which can target the adsorption of calcium ions in the manganese ore leachate, and the removal rate of calcium ions in the manganese ore leachate is not less than 96%, and the removal rate of manganese ions is not more than 2%, reducing the loss of manganese elements. Compared with the embodiment of the present application, the methods provided in comparative examples 1 and 3 have poor calcium ion removal rates and also remove a large amount of manganese elements. Although comparative example 2 has a high calcium ion removal rate, it also removes a large amount of manganese elements and introduces impurity element S. In addition, comparative example 1 also introduces impurity element F. Obviously, each comparative example cannot obtain the impurity removal effect of the embodiment of the present application.

[0162] In addition, the calcium-removing manganese ore leachate obtained in the above Example 1 is used as a manganese source and applied to the preparation of a positive electrode material for a lithium manganese iron phosphate battery. The specific steps are as follows:

[0163] 1. Mix appropriate amount of manganese ore and acid solution, stir evenly, react fully, and filter to obtain calcium manganese nitrate solution.

[0164] 2. Add 2% active manganese dioxide by weight to the filtrate of step 1, react at 25° C. for 5 h, and filter to obtain a calcium-removed manganese nitrate solution.

[0165] 3. Add an appropriate amount of iron sulfate to the filtrate of step 2, react at 90°C for 8 hours, and filter to obtain potassium-free manganese nitrate solution. The reaction equation is: 3Fe2(SO4)3+12H2O+K2SO4=K2Fe6(SO4)4(OH) 12 +6H2SO4.

[0166] 4. Add the molar amount of Mn to the filtrate of step 3. x Fe 1-x PO4 is added into an appropriate amount of iron salt solution and an appropriate amount of phosphate salt solution, and crystallized at 120°C for 4 hours, and then ferromanganese phosphate is obtained by filtration.

[0167] 5. Using the above-mentioned manganese iron phosphate precursor to prepare lithium manganese iron phosphate material, including: according to the molecular formula Mn x Fe 1-x PO4, lithium source and manganese iron phosphate precursor are mixed evenly in a molar ratio of 1.1:1, 12% of carbon source is added to the mixture, heated to 500°C under nitrogen, kept warm for 7 hours, and cooled to room temperature to obtain lithium manganese iron phosphate.

[0168] The lithium iron manganese phosphate material prepared in the embodiment of the present application has broad application prospects in lithium-ion batteries.

[0169] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. An adsorption material, characterized in that: The adsorption material includes porous manganese dioxide, and pores are distributed at least on the surface of the porous manganese dioxide. The ratio of the pore diameter to the diameter of the calcium ion is (1-1.5):

1.

2. The adsorbent material according to claim 1, characterized in that The diameter of the pores is 0.2 nm to 0.3 nm.

3. The adsorbent material according to claim 1 or 2, characterized in that The particle size of the porous manganese dioxide is 2200nm to 5000nm; And / or, the specific surface area of ​​the porous manganese dioxide is 200m 2 / g~330m 2 / g; And / or, the pore volume of the porous manganese dioxide is 0.1 cm 3 / g~0.8cm 3 / g; And / or, the porosity of the porous manganese dioxide is 30% to 95%.

4. A method for preparing an adsorbent material, characterized in that: The steps include: Dissolving a soluble manganese source, an oxidant and a soluble calcium salt into a solution for mixed reaction to obtain manganese dioxide adsorbing calcium ions; The calcium ions in the manganese dioxide adsorbing calcium ions are eluted and removed to obtain porous manganese dioxide.

5. The method for preparing an adsorbent material according to claim 4, characterized in that: The mixing reaction step comprises: preparing the calcium salt into a calcium salt solution, and sequentially adding the manganese source and the oxidant to react; And / or, the molar ratio of the calcium element in the calcium salt, the manganese element in the manganese source and the oxidant is (1-2.2):1:(1.5-5); And / or, the step of eluting to remove calcium ions comprises: eluting the manganese dioxide adsorbing calcium ions with a solvent, and then separating the solid from the liquid; And / or, the calcium salt includes at least one of calcium chloride, calcium gluconate, calcium dihydrogen phosphate, calcium nitrate, calcium bicarbonate, calcium bisulfate, calcium bisulfite, calcium hypochlorite, calcium bromide, calcium iodide, calcium chlorate, calcium perchlorate, and calcium permanganate; And / or, the manganese source includes at least one of manganese sulfate, manganese chloride, manganese nitrate, potassium permanganate, manganese acetate, and manganese dihydrogen phosphate; And / or, the oxidant includes at least one of hydrogen peroxide, potassium permanganate, nitric acid, oxygen and ozone.

6. The method for preparing an adsorbent material according to claim 5, characterized in that: The solvent used for eluting and removing calcium ions includes at least one of water, dilute nitric acid, ethanol, acetic acid, dilute hydrochloric acid, dilute sulfuric acid, and methanol; And / or, the mass concentration of the calcium salt solution is 5% to 15%.

7. A method for removing calcium from a manganese-containing solution, characterized in that: The following steps are involved: obtaining a manganese-containing solution, wherein the manganese-containing solution contains calcium ions; The adsorption material according to any one of claims 1 to 3 and / or the adsorption material prepared by the method according to any one of claims 4 to 6 is mixed with the manganese-containing solution for adsorption treatment to obtain a calcium-removed manganese-containing solution.

8. The method for decalcifying a manganese-containing solution as claimed in claim 7, characterized in that: The mass ratio of the adsorption material to the manganese-containing solution is (1% to 3%):

1.

9. The method for decalcifying a manganese-containing solution according to claim 7 or 8, characterized in that: The manganese-containing solution includes a manganese ore leaching solution, and the preparation of the manganese ore leaching solution includes the steps of: mixing manganese ore with an acid hydrolysis solution to obtain the manganese ore leaching solution.

10. The method for decalcifying a manganese-containing solution according to claim 9, characterized in that: The molar ratio of the manganese element in the manganese ore to the acid hydrolysis solution is 1:(1-3); and / or, the acidolysis solution comprises at least one of nitric acid, hydrochloric acid, sulfuric acid, water and nitrogen oxides, water and sulfur dioxide; And / or, the manganese ore includes at least one of rhodochrosite and pyrolusite.

11. A method for preparing a manganese-containing positive electrode material, characterized in that: The manganese source for preparing the manganese-containing positive electrode material adopts the decalcified manganese-containing solution prepared by the method for decalcifying the manganese-containing solution as claimed in any one of claims 7 to 10.

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