Method for preparing magnetic adsorption material from injection molding neodymium iron boron waste and application of magnetic adsorption material

Abstract

The invention discloses a method for preparing a magnetic adsorption material from injection molding neodymium iron boron waste and application thereof, and the method comprises the following steps: S1, carrying out thermogravimetric analysis on a sample of the injection molding neodymium iron boron waste so as to accurately determine the thermal stability characteristic of the sample; s2, carrying out carbonization treatment on the sample under the protection of a nitrogen atmosphere; s3, after carbonization, grinding a product in a ball mill for 1 hour, and screening through a screen to obtain an adsorption material; and S4, carrying out an adsorption test on Cu ions by using the adsorption material obtained in S3. According to the method for preparing the magnetic adsorption material for adsorption application by carbonizing the resin and retaining the magnetism, high-value utilization of waste materials is achieved, and the method has important significance in the fields of recycling of electrochemical energy storage materials and environmental protection.

Description

Technical Field

[0001] The invention relates to the technical field of magnetic adsorption material preparation, and in particular to a method for preparing magnetic adsorption material from injection-molded NdFeB waste materials and application thereof. Background Art

[0002] Injection molding NdFeB waste is generated in the process of producing high-performance NdFeB permanent magnet materials, including machining debris, scraps, sludge debris, and raw materials remaining during grinding, pressing and roasting. It contains a large amount of rare earth elements such as neodymium, praseodymium, dysprosium, etc., and has important recycling value.

[0003] The global demand for rare earth resources is growing, especially in key areas such as new energy, aerospace, and national defense. However, if the waste generated during the mining and utilization of rare earth resources is not properly handled, it will cause serious environmental pollution and waste precious rare earth resources. Therefore, the development of effective waste recycling technology is of great significance to promote the recycling of rare earth resources and reduce environmental pollution. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for preparing a magnetic adsorption material from injection molded NdFeB waste and its application. The method prepares a magnetic adsorption material for adsorption applications by carbonizing the resin and retaining the magnetism, thereby realizing high-value utilization of the waste and having important significance for the recycling of electrochemical energy storage materials and the environmental protection field.

[0005] In order to solve the above technical problems, the present invention provides a method for preparing a magnetic adsorption material by injection molding NdFeB waste and its application, comprising the following steps: S1: Perform thermogravimetric analysis on samples of NdFeB injection molding waste to accurately determine its thermal stability characteristics; S2: The sample is carbonized under the protection of a nitrogen atmosphere; S3: After carbonization, the product was ground in a ball mill for 1 hour, and then screened through a sieve to obtain an adsorption material; S4: Use the adsorption material obtained in S3 to carry out adsorption test of Cu ions.

[0006] Furthermore, in step S3, the rotation speed of the ball mill is set to 433 rpm, and the screen is selected to have a size of 120 mesh.

[0007] Furthermore, in step S4, the environmental data used in the test are as follows: The concentration range of Cu ions was set at 20ppm-400ppm, and the solid-liquid ratio was controlled at 0.5-4g / L, so as to comprehensively examine the adsorption capacity and effect of the magnetic adsorption material on Cu ions in wastewater, and provide reliable experimental basis and technical support for its practical application in the field of wastewater treatment.

[0008] Beneficial effects of the present invention: The present invention uses rubidium iron boron injection molding waste as raw material to prepare magnetic adsorption material, realizes high-value resource utilization of waste, effectively reduces dependence on primary resources, conforms to the concept of circular economy, and reduces the environmental pressure caused by improper waste disposal from the source, providing a new path for solving the rubidium iron boron waste pollution problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is the sample weight curve of the present invention.

[0010] Figure 2 It is the relationship diagram between the solid-liquid ratio and the adsorption capacity of the present invention.

[0011] Figure 3 It is the relationship diagram between Cu2+ concentration and adsorption capacity of the present invention.

[0012] Figure 4 It is the relationship diagram between adsorption time and adsorption capacity of the present invention.

[0013] Figure 5 is the XRD spectrum of the sample of the present invention. DETAILED DESCRIPTION

[0014] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0015] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0016] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0017] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0018] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0019] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0020] Reference Figures 1 to 4 As shown, the present invention discloses a method for preparing a magnetic adsorption material from injection molded NdFeB waste and its application, comprising the following steps: S1: performing thermogravimetric analysis on a sample of NdFeB injection molded waste to accurately determine its thermal stability characteristics; S2: carbonizing the sample under the protection of a nitrogen atmosphere; S3: after carbonization, grinding the product in a ball mill for 1 hour, and then screening it through a sieve to obtain an adsorption material; S4: using the adsorption material obtained in S3 to carry out an adsorption test on Cu ions.

[0021] Among them, in step S3, the rotation speed of the ball mill is set to 433 rpm, and the screen size is 120 mesh; in step S4, the environmental data used in the test are as follows: the concentration range of Cu ions is set at 20ppm-400ppm, and the solid-liquid ratio is controlled at 0.5-4g / L, so as to comprehensively examine the adsorption capacity and effect of the magnetic adsorption material on Cu ions in wastewater, and provide reliable experimental basis and technical support for its practical application in the field of wastewater treatment.

[0022] Three specific embodiments are listed below: Example 1 A sample of rubidium iron boron injection molding waste was selected and placed in a tubular furnace. It was carbonized at 450°C for 2 hours under a protective atmosphere with a nitrogen flow rate of 10 mL / min. The obtained product was ground in a ball mill at a speed of 433 rpm for 1 hour, and then screened with a 120-mesh screen to obtain an adsorbent material, numbered RuC. For simulated wastewater with a Cu2+ concentration of 100 ppm, the adsorbent material was added at a solid-liquid ratio of 0.5-5 g / L and placed in an oscillator at 200 r / min. After the adsorption reaction was carried out for 2 hours, the Cu ion concentration in the wastewater was determined by atomic absorption spectroscopy, and it was found that its adsorption capacity could reach 124 mg / g, showing good adsorption potential.

[0023] Example 2 The rubidium iron boron injection molding waste sample was carbonized at 500 ° C for 2 hours. Then the carbonized product was put into a ball mill, ground at a predetermined speed for 1 hour and screened. The solid-liquid ratio was set to 0.5g / L for adsorption test. The initial pH of 20, 50, 100, 150, 200, 300, and 400mg / L copper solutions was adjusted to 4.5 with 1mol / LHCl and NaOH, and 0.5g / L magnetic carbon-based functional material was added, placed in an oscillator at 200r / min, the adsorption time was 2h, and filtered, and the concentration of Cu2+ in the filtrate was detected by atomic absorption.

[0024] Example 3 The rubidium iron boron injection molding waste sample was carbonized at 500°C for 2 hours. Then the carbonized product was put into a ball mill, ground at a predetermined speed for 1 hour and screened. For the simulated wastewater with a Cu ion concentration of 100ppm, the solid-liquid ratio was set to 0.5g / L for adsorption test. The copper solution was adjusted to an initial pH of 4.5 with 1mol / LHCl and NaOH, and 0.5g / L of magnetic carbon-based functional material was added, placed in an oscillator at 200r / min, the adsorption time was 10min-120min, and filtered, and the concentration of Cu2+ in the filtrate was detected by atomic absorption.

[0025] The present invention uses polymer low-temperature carbonization technology to convert polymer materials in injection molded NdFeB waste into porous carbon materials with high specific surface area while retaining the magnetic properties of the waste. This porous carbon material can not only be used as an efficient magnetic adsorption material for water treatment, pollutant removal and other fields, but also as a high-performance electrode material for energy storage devices such as supercapacitors and lithium-ion batteries. This technology adopts a one-step carbonization method and uses transition metal oxides to promote the carbonization of waste polyester at a relatively low temperature, providing a new method for converting a large amount of cheap urban and industrial waste polyester into high-value-added porous carbon materials.

[0026] The above-described embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art based on the present invention are within the protection scope of the present invention. The protection scope of the present invention shall be subject to the claims.

Claims

1. A method for preparing magnetic adsorption material by injection molding NdFeB waste and its application, characterized in that: The steps include: S1: Perform thermogravimetric analysis on samples of NdFeB injection molding waste to accurately determine its thermal stability characteristics; S2: The sample is carbonized under the protection of a nitrogen atmosphere; S3: After carbonization, the product was ground in a ball mill for 1 hour, and then screened through a sieve to obtain an adsorption material; S4: Use the adsorption material obtained in S3 to carry out adsorption test of Cu ions.

2. The method for preparing magnetic adsorption material from injection molded NdFeB waste and its application as claimed in claim 1, characterized in that: In step S3, the rotation speed of the ball mill is set to 433 rpm, and the screen is selected to have a size of 120 mesh.

3. The method for preparing magnetic adsorption material from injection molded NdFeB waste and its application as claimed in claim 1, characterized in that: In step S4, the environmental data used in the test are as follows: The concentration range of Cu ions was set at 20ppm-400ppm, and the solid-liquid ratio was controlled at 0.5-4g / L, so as to comprehensively examine the adsorption capacity and effect of the magnetic adsorption material on Cu ions in wastewater, and provide reliable experimental basis and technical support for its practical application in the field of wastewater treatment.

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