Nitrogen- and carbon-containing aluminum iron boride composite materials, their preparation methods and applications

Abstract

This invention discloses a nitrogen-carbon-containing aluminum iron boride composite material, its preparation method and application. The nitrogen-carbon-containing aluminum iron boride composite material has the characteristics of high catalytic efficiency, low leaching, easy recovery and high stability, and has considerable application potential in activated persulfate advanced oxidation systems.

Description

Technical Field

[0001] This invention belongs to the field of environmental nanomaterials, specifically relating to a nitrogen-carbon-containing aluminum iron boride composite material, its preparation method, and its application. Background Technology

[0002] In recent years, with the rapid development of detection technology, highly toxic and recalcitrant trace persistent organic pollutants in water, such as pesticides, flame retardants, and antibiotics, have received increasing attention. Traditional wastewater treatment methods struggle to achieve efficient and complete degradation of these pollutants. Persulfate advanced oxidation technology, due to its ability to generate various high-potential free radicals and reactive oxygen species, is attracting growing attention as a promising technology. Methods for activating persulfate are mainly divided into homogeneous catalysis and heterogeneous catalysis. Homogeneous catalysis uses recyclable solid-phase catalysts to initiate the persulfate reaction and produce active substances. Finding more efficient and stable catalysts is one of the key tasks in promoting the development of persulfate advanced oxidation systems.

[0003] Transition metal materials often exhibit highly efficient catalytic activity; however, metal leaching remains a persistent challenge. Carbon materials possess advantages such as large specific surface area, strong adsorption capacity, and well-developed pore structure, yet their catalytic performance is less than satisfactory. Therefore, developing metal-nonmetal composite materials that combine high efficiency and environmental friendliness is a new trend in heterogeneous catalyst research. Summary of the Invention

[0004] 1. The problem to be solved

[0005] To address the problems of low catalytic efficiency and poor stability in the application of existing heterogeneous catalysts, one of the objectives of this invention is to provide a nitrogen-doped carbon-coated aluminum iron borate composite material, which can be used as a catalyst to efficiently activate persulfate.

[0006] Meanwhile, the present invention also provides a method for preparing the nitrogen-doped carbon-coated aluminum iron boride composite material, and the application of the nitrogen-doped carbon-coated aluminum iron boride composite material as a heterogeneous catalyst.

[0007] 2. Technical Solution

[0008] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0009] According to one of the objectives of this invention, the present invention provides a method for preparing a nitrogen-carbon-containing aluminum iron boride composite material, comprising the steps of:

[0010] S1. Prepare a powder material containing Fe, Al, and B, and subject the powder material to high-temperature plasma sintering to obtain aluminum iron boride powder.

[0011] S2. Prepare a mixture containing aluminum iron boron powder and carbon and nitrogen organic matter;

[0012] The mass ratio of the aluminum iron boride powder to the carbon and nitrogen-containing organic matter is (0.1-0.3):2.

[0013] S3. The mixture is subjected to high-temperature sintering treatment;

[0014] The conditions for the high-temperature treatment include:

[0015] In an inert gas atmosphere,

[0016] First, maintain the temperature at 500–600℃ for 2–4 hours (first stage sintering).

[0017] Then maintain at 800-1000℃ for 4-8 hours (second stage sintering).

[0018] According to any embodiment of the first aspect of the present invention, the method for preparing nitrogen-containing carbon-containing aluminum iron boron composite material uses nitrogen, argon, or helium as the inert gas.

[0019] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, in step S2, the mass ratio of the aluminum iron boride powder and the carbon-nitrogen-containing organic matter is preferably (0.1-0.3):2, (0.15-0.25):2, (0.18-0.22):2, and 0.2:2.

[0020] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, in step S2, the sintering temperature of the first stage is preferably 500-600℃, 525-580℃, and 550℃ respectively.

[0021] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, in step S2, the sintering time of the first stage is preferably 2-4 h, 2.5-3.5 h, and 3 h respectively.

[0022] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, in step S2, the sintering temperature of the second stage is preferably 800-1000℃, 850-950℃, and 900℃ respectively.

[0023] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, in step S2, the sintering time of the second stage is preferably 4-8h, 5-7h, and 6h respectively.

[0024] According to any embodiment of the first aspect of the present invention, the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, step S1 includes first grinding the powder material and then performing high-temperature plasma sintering, wherein the grinding conditions include:

[0025] Grind at 600-800 rpm for 7-15 minutes.

[0026] In the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material according to any embodiment of the first aspect of the present invention, the grinding speed is preferably 600-800 rpm, 650-750 rpm, and 700 rpm respectively.

[0027] In the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material according to any embodiment of the first aspect of the present invention, the grinding time is preferably 7-15 min, 8-12 min, and 10 min respectively.

[0028] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, the conditions for the high-temperature plasma sintering in step S1 include:

[0029] The sintering temperature is 1000~1200℃, and the sintering speed is 0.10~0.50cm / s.

[0030] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, the preferred temperatures for high-temperature plasma sintering are 1000–1200°C, 950–1150°C, 1000–1150°C, and 1110°C.

[0031] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, the preferred high-temperature plasma sintering speeds are 0.10–0.50 cm / s, 0.20–0.50 cm / s, 0.30–0.40 cm / s, and 0.37 cm / s, respectively.

[0032] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, in step S1, the molar ratio of Fe, Al, and B is preferably 2:(1.1~1.5):2, 2:(1.1~1.4):2, 2:(1.1~1.3):2, 2:(1.1~1.2):2, and 2:(1.1~1.15):2.

[0033] According to any embodiment of the first aspect of the present invention, the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, step S2 includes:

[0034] Prepare a mixture containing aluminum iron boride powder and carbon and nitrogen-containing organic matter;

[0035] The mixture is stirred and dried to obtain the mixture material.

[0036] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, the solvent of the mixture is a mixture comprising water and alcohol.

[0037] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, the volume ratio of water to alcohol is 4:(0.5-2).

[0038] According to any embodiment of the first aspect of the present invention, the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, wherein the alcohol includes low carbon alcohols of C1-C4; preferably, the alcohol is methanol.

[0039] In the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material according to any embodiment of the first aspect of the present invention, in step S3, the heating rate is 3-5 °C / min.

[0040] According to any embodiment of the first aspect of the present invention, in the method for preparing nitrogen-containing carbon-containing aluminum iron boride composite material, in step S2, the temperature of the drying treatment does not exceed 185°C;

[0041] Preferably not exceeding 180℃;

[0042] A further preferred temperature is 150–180°C.

[0043] A second aspect of the present invention provides a nitrogen-carbon-containing aluminum iron boride composite material, the nitrogen-carbon-containing aluminum iron boride composite material comprising: aluminum iron boride powder;

[0044] In addition, nitrogen and carbon elements are attached to the aluminum iron boron powder.

[0045] The nitrogen-containing carbon-containing aluminum iron boride composite material according to any embodiment of the second aspect of the present invention is prepared by the method according to any embodiment of the first aspect of the present invention.

[0046] A third aspect of the present invention provides the application of nitrogen- and carbon-containing aluminum iron boride composite materials as heterogeneous catalysts.

[0047] The application of the nitrogen-containing carbon-containing aluminum iron borate composite material according to any embodiment of the third aspect of the present invention as an activator of persulfate.

[0048] The application of the nitrogen-carbon-containing aluminum iron boride composite material according to any embodiment of the third aspect of the present invention, wherein the nitrogen-carbon-containing aluminum iron boride composite material is prepared by the method according to any embodiment of the first aspect of the present invention, or as the nitrogen-carbon-containing aluminum iron boride composite material according to any embodiment of the second aspect of the present invention.

[0049] Beneficial effects

[0050] (1) The nitrogen-carbon-containing aluminum iron boride composite material provided by the present invention includes aluminum iron boride powder and nitrogen and carbon elements attached to the aluminum iron boride powder, wherein the nitrogen and carbon are located on the surface of the aluminum iron boride particles and form a coating on the aluminum iron boride particles;

[0051] The aluminum iron boronide is an iron-based ceramic material with strong magnetic properties. When used in a catalytic system, it is easy to recover and will not cause metal leaching, and it is very stable. At the same time, the nitrogen and carbon (or nitrogen-doped carbon) on the surface of the aluminum iron boronide particles can effectively enhance catalytic activity and improve catalytic efficiency.

[0052] (2) The nitrogen-containing carbon iron boron aluminum composite material provided by the present invention is used as a heterogeneous catalyst, such as a persulfate catalyst. It has both the high activity of metal catalysts and the environmental friendliness of non-metal catalysts. Its high catalytic efficiency, low leaching, easy recovery and high stability make it have considerable application potential in heterogeneous catalysis and activation of persulfate advanced oxidation systems.

[0053] (3) The method for preparing nitrogen-containing carbon-containing aluminum iron boron composite material provided by the present invention is simple, easy to implement, and inexpensive, and is suitable for industrial production. Attached Figure Description

[0054] Figure 1 The images show the effects of nitrogen-containing carbon-containing aluminum iron boride composite material prepared in Example 1 and aluminum iron boride material obtained in Comparative Example 1 on the activation of persulfate degradation of sulfonamides.

[0055] In the picture:

[0056] PMS indicates that only persulfate is added to degrade the organic pollutant sulfonamide;

[0057] MBA-PMS indicates the addition of Fe2AlB2 powder and persulfate to degrade the organic pollutant sulfonamide;

[0058] MBA@NC states that it only adds nitrogen-containing carbon-containing aluminum iron boron compound to degrade the organic pollutant sulfonamide;

[0059] MBA@NC-PMS indicates the addition of nitrogen-containing carbon-containing aluminum iron boron compound and persulfate to degrade the organic pollutant sulfonamide. Detailed Implementation

[0060] This disclosure will be more readily understood by referring to the following description, taken in conjunction with the accompanying drawings and examples, all of which form part of this disclosure. It should be understood that this disclosure is not limited to the specific products, methods, conditions, or parameters described and / or illustrated herein. Furthermore, the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting, unless otherwise stated.

[0061] It should also be understood that, for clarity, certain features of this disclosure may be described herein in the context of individual embodiments, but may also be provided in combination with each other in individual embodiments. That is, unless obviously incompatible or specifically excluded, each individual embodiment is considered to be combinable with any other embodiment, and such combination is considered to represent another different embodiment. Conversely, for brevity, various features of this disclosure described in the context of individual embodiments may also be provided individually or in any sub-combination. Finally, while a particular embodiment may be described as part of a series of steps or part of a more general structure, each step or substructure may also be considered an independent embodiment in itself.

[0062] Unless otherwise stated, it should be understood that each individual element in the list and each combination of individual elements in the list will be interpreted as a different embodiment. For example, a list of embodiments denoted as "A, B, or C" should be interpreted as including embodiments "A", "B", "C", "A or B", "A or C", "B or C", or "A, B, or C".

[0063] In this disclosure, the singular forms of the articles “a,” “an,” and “the” also include the corresponding plural references, and references to a particular value include at least that particular value, unless the context clearly indicates otherwise. Thus, for example, a reference to “substance” is a reference to at least one of such substance and its equivalents.

[0064] Terms including ordinal numbers such as "first" and "second" may be used to describe various components or fluids, but these components and fluids are not limited by these terms. Therefore, without departing from the teachings of this disclosure, these terms are used only to distinguish one component / fluid from another.

[0065] When an item is described using the integrative terms “...and / or ...", the description should be understood to include any of the associated listed items and all combinations thereof; for example, A and / or B should be interpreted as an embodiment that includes “A” but not “B”, an embodiment that includes “B” but not “A”, or an embodiment that includes both “A” and “B”.

[0066] Generally, the use of the term "about" indicates an approximation that can vary depending on the desired characteristics obtained from the disclosed subject matter and will be interpreted in a context-dependent manner based on function. Therefore, those skilled in the art will be able to interpret a degree of difference on a case-by-case basis. In some cases, the number of significant figures used when expressing a particular value can be a representative technique for determining the difference allowed by the term "about." In other cases, a gradient within a range of values ​​can be used to determine the range of differences allowed by the term "about." Furthermore, all ranges in this disclosure are inclusive and composable, and references to values ​​described within a range include every value within that range.

[0067] Throughout the description of this application, when a part is described as "including" a certain element, it does not mean that other elements are excluded, but rather that other elements may be included, unless otherwise expressly stated to the contrary.

[0068] Throughout this specification, when a step is described as being "above" or "before" other steps, this includes not only cases where the step has a direct temporal sequence relationship with the other steps, but also cases where the temporal sequence of two steps changes, such as a mixed step following each step, and where there is an indirect temporal sequence relationship.

[0069] Throughout this specification, the phrase “any embodiment of the first aspect of the first object of the present invention…” does not mean the exclusion of any constituent elements of the described scheme that appear before or after it, but rather means that other constituent elements may also be included, unless otherwise expressly stated to the contrary.

[0070] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terms used herein and / or include any and all combinations of one or more of the associated listed items.

[0071] To demonstrate the technical solutions and advantages of the present invention, the technical solutions in the embodiments of the present invention will be described in full below.

[0072] Example 1

[0073] This embodiment provides a nitrogen- and carbon-containing aluminum iron boride composite material according to the following steps:

[0074] S1. Fe powder, Al powder, and B powder are added in a molar ratio of 2:1.12:2 and mixed in a planetary ball mill at 700 rpm for 10 min to obtain a powder containing Fe, Al, and B. The powder is then subjected to high-temperature plasma sintering (sintering temperature of 1110℃ and sintering speed of 0.37 cm / s) to obtain aluminum iron boride powder, denoted as Fe2AlB2 powder.

[0075] S2. Take 0.2g of Fe2AlB2 powder obtained in step S1 and 2g of melamine and disperse them in a mixed solution containing 80mL of distilled water and 20mL of methanol. Stir vigorously for 15 minutes, then transfer the mixture to an oil bath at 180℃. After the solution is completely dried, grind it to obtain a mixture containing aluminum iron boride powder and carbon and nitrogen organic matter.

[0076] S3. The mixture is subjected to high-temperature sintering treatment;

[0077] The high-temperature treatment conditions are as follows: heating at 5℃ / min, pyrolysis at 550℃ in a N2 atmosphere for 3 hours, and then holding at 900℃ for 6 hours to obtain a nitrogen-carbon-containing aluminum iron boride composite material, named MAB@NC.

[0078] Example 2

[0079] This embodiment provides a nitrogen- and carbon-containing aluminum iron boride composite material according to the following steps:

[0080] S1. Fe powder, Al powder, and B powder are added in a molar ratio of 2:1.5:2 and mixed in a planetary ball mill at 800 rpm for 7 min to obtain a powder containing Fe, Al, and B. The powder is then subjected to high-temperature plasma sintering (sintering temperature of 1000℃ and sintering speed of 0.15 cm / s) to obtain aluminum iron boride powder, denoted as Fe2AlB2 powder.

[0081] S2. Take 0.1g of Fe2AlB2 powder obtained in step S1 and 2g of melamine and disperse them in a mixed solution containing 80mL of distilled water and 20mL of methanol. Stir vigorously for 20 minutes, then transfer the mixture to an oil bath at 150℃. After the solution is completely dried, grind it to obtain a mixture containing aluminum iron boride powder and carbon and nitrogen organic matter.

[0082] S3. The mixture is subjected to high-temperature sintering treatment;

[0083] The high-temperature treatment conditions are as follows: heating at 3℃ / min, pyrolyzing in a N2 atmosphere at 500℃ for 4 hours, and then maintaining at 1000℃ for 4 hours to obtain a nitrogen-carbon-containing aluminum iron boride composite material, named MAB@NC-2.

[0084] Example 2

[0085] This embodiment provides a nitrogen- and carbon-containing aluminum iron boride composite material according to the following steps:

[0086] S1. Fe powder, Al powder, and B powder are added in a molar ratio of 2:1.1:2 and mixed in a planetary ball mill at 600 rpm for 15 min to obtain a powder containing Fe, Al, and B. The powder is then subjected to high-temperature plasma sintering (sintering temperature of 1200℃ and sintering speed of 0.45 cm / s) to obtain aluminum iron boron powder, denoted as Fe2AlB2 powder.

[0087] S2. Take 0.3g of Fe2AlB2 powder obtained in step S1 and 2g of melamine and disperse them in a mixed solution containing 80mL of distilled water and 20mL of methanol. Stir vigorously for 20 minutes, then transfer the mixture to an oil bath at 160℃. After the solution is completely dried, grind it to obtain a mixture containing aluminum iron boride powder and carbon and nitrogen organic matter.

[0088] S3. The mixture is subjected to high-temperature sintering treatment;

[0089] The high-temperature treatment conditions are as follows: heating at 4℃ / min, pyrolyzing in a N2 atmosphere at 600℃ for 2 hours, and then maintaining at 800℃ for 8 hours to obtain a nitrogen-carbon-containing aluminum iron boride composite material, named MAB@NC-3.

[0090] Comparative Example 1

[0091] This comparative example provides a nitrogen- and carbon-containing aluminum iron boron composite material according to the following steps:

[0092] S1. Fe powder, Al powder, and B powder are added in a molar ratio of 2:1.12:2 and mixed in a planetary ball mill at 700 rpm for 10 min to obtain a powder containing Fe, Al, and B. The powder is then subjected to high-temperature plasma sintering (sintering temperature of 1110℃ and sintering speed of 0.37 cm / s) to obtain aluminum iron boride powder, denoted as Fe2AlB2 powder, and named MAB.

[0093] Comparative Example 2

[0094] This comparative example is basically the same as Example 1, except that:

[0095] In step S2, the amount of Fe2AlB2 powder used is 0.4g, and the amount of melamine used is 2g;

[0096] The rest is the same as in Example 1, and a nitrogen-carbon-containing aluminum iron boride composite material is obtained, named D-MAB@NC-1.

[0097] Comparative Example 3

[0098] This comparative example is basically the same as Example 1, except that:

[0099] In step S2, the amount of Fe2AlB2 powder used is 0.6g, and the amount of melamine used is 2g;

[0100] The rest is the same as in Example 1, and a nitrogen-carbon-containing aluminum iron boride composite material is obtained, named D-MAB@NC-2.

[0101] Example 4

[0102] In this embodiment, the materials prepared in Example 1 and Comparative Examples 1-3 are used as catalysts to catalyze the degradation of the organic pollutant sulfanilamide by persulfate (PMS). Specifically:

[0103] The performance of activated persulfate in degrading sulfonamides was tested using a Waters Alliance HPLC system from Waters Technology (Shanghai) Co., Ltd. First, 100 mL of a sulfonamide solution with a concentration of 10 mg / L was prepared. Then, 5 mg of the different catalysts prepared above were added to the sulfonamide solution and mixed thoroughly. Finally, 1 mM persulfate was added to initiate the reaction.

[0104] like Figure 1 As shown, under room temperature and unadjusted pH conditions, the addition of 5 mg of the MAB@NC catalyst prepared in Example 1 can achieve complete degradation of sulfonamides within 10 min; the addition of 5 mg of the MAB prepared in Comparative Example 1 can only achieve about 50% degradation of sulfonamides within 10 min under the same conditions.

[0105] At room temperature and without pH adjustment, the degradation rate of sulfonamides by the D-MAB@NC-1 catalyst prepared by adding 5 mg of Comparative Example 2 was less than 50% within 10 min under the same conditions; the degradation rate of sulfonamides by the D-MAB@NC-2 catalyst prepared by adding 5 mg of Comparative Example 3 was less than 50% within 10 min under the same conditions.

[0106] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a nitrogen- and carbon-containing aluminum iron boride composite material for catalyzing the degradation of organic pollutants by persulfate, characterized in that, Including the following steps: S1. Prepare a powder material containing Fe, Al, and B, and subject the powder material to high-temperature plasma sintering to obtain aluminum iron boride powder. S2. Prepare a mixture containing aluminum iron boron powder and carbon and nitrogen organic matter; The mass ratio of the aluminum iron boride powder to the carbon and nitrogen-containing organic matter is (0.1~0.3):2; S3. The mixture is subjected to high-temperature sintering treatment; The conditions for the high-temperature treatment include: In an inert gas atmosphere, First, maintain at 500~600 ℃ for 2~4 h. Then keep it at 800~1000℃ for 4~8 hours.

2. The preparation method according to claim 1, characterized in that, Step S1 includes first grinding the powder material, and then performing high-temperature plasma sintering. The grinding conditions include: Grind at 600-800 rpm for 7-15 minutes.

3. The preparation method according to claim 1, characterized in that, In step S1, the conditions for the high-temperature plasma sintering include: The sintering temperature is 1000~1200 ℃, and the sintering speed is 0.10~0.50 cm / s.

4. The preparation method according to any one of claims 1 to 3, characterized in that, In step S1, the molar ratio of Fe, Al, and B is 2:(1.1~1.5):

2.

5. The preparation method according to claim 4, characterized in that, Step S2 includes: Prepare a mixture containing aluminum iron boride powder and carbon and nitrogen-containing organic matter; The mixture is stirred and dried to obtain the mixture material.

6. The preparation method according to claim 5, characterized in that, The solvent of the mixture is a mixture of water and alcohol.

7. The preparation method according to claim 6, characterized in that, The volume ratio of water to alcohol is 4:(0.5~2).

8. The preparation method according to any one of claims 1 to 3, characterized in that, In step S3, the heating rate is 3~5℃ / min.

9. The nitrogen- and carbon-containing aluminum iron boride composite material prepared by the method according to any one of claims 1 to 8, characterized in that, The nitrogen- and carbon-containing aluminum iron boride composite material includes: Aluminum boron oxide powder; And nitrogen and carbon elements attached to the aluminum iron boron powder.

10. The application of the nitrogen-containing carbon-containing aluminum iron boron composite material as described in claim 9, characterized in that, The nitrogen- and carbon-containing aluminum iron borate composite material is used to catalyze the degradation of organic pollutants by persulfate.

Images