Preparation method and application of aluminum-iron-carbon composite material for continuously activating zero-valent aluminum

Abstract

The present invention provides a preparation method of an aluminum-iron-carbon composite material for realizing continuous activation of zero-valent aluminum, comprising the following steps: placing aluminum powder, iron powder, activated carbon and ball milling beads in a ball milling tank, evacuating and sealing it, and then carrying out ball milling treatment under an inert atmosphere to obtain the aluminum-iron-carbon composite material. The present invention also provides an environmental remediation application of the aluminum-iron-carbon composite material in removing pollutants in wastewater. When the aluminum-iron-carbon composite material enters the solution, a large number of microscopic corrosion primary batteries are formed between aluminum-carbon and iron-carbon. Hydrolysis reaction occurs on the surface of the activated carbon to form a local alkaline environment, which promotes the activation of zero-valent aluminum and maintains the reaction activity under the action of the galvanic cathode effect, and can quickly and effectively remove pollutants in water. The aluminum-iron-carbon composite material prepared by the present invention is environmentally friendly, has a wide range of application scenarios, strong reaction activity, can continuously dissolve and output electrons without passivation phenomenon, and also has the advantages of wide raw material sources, low cost, simple preparation method and fast removal rate, and is easy to be applied in engineering.

Description

Technical Field

[0001] The present invention belongs to the technical field of water pollution treatment, and specifically relates to a preparation method of an aluminum-iron-carbon composite material for realizing continuous activation of zero-valent aluminum, and also relates to the application of an aluminum-iron-carbon composite material for realizing continuous activation of zero-valent aluminum in removing pollutants in wastewater. Background Art

[0002] Zero-valent metal aluminum is the most abundant metal material in the earth's crust, with extremely high reactivity (standard redox potential -1.67V), low cost, light weight, and environmental friendliness. Compared with zero-valent iron, it has greater potential for environmental applications. However, the dense oxide layer on the surface of aluminum powder hinders the release of electrons, greatly limiting the reactivity of zero-valent aluminum, resulting in extremely low removal efficiency of pollutants by zero-valent aluminum under near-neutral conditions. Currently, the commonly used methods for removing the aluminum oxide film are pickling and mechanical treatment. However, the treated materials usually still need to maintain activity under strong acidic or strong alkaline conditions (pH < 4 or pH > 10), and pickling and mechanical treatment with additives are prone to cause secondary environmental pollution. In addition, after the treated zero-valent aluminum metal surface reacts with the environmental medium, an oxide layer will be further generated, resulting in secondary passivation of the material. The oxide layer on the surface of zero-valent aluminum is the biggest bottleneck hindering its application in environmental remediation.

[0003] Based on this, it is of great significance to research and develop a technology that can activate zero-valent aluminum, remove the oxide layer, and keep zero-valent aluminum continuously reactive. Summary of the Invention

[0004] One of the purposes of the present invention is to provide a preparation method of an aluminum-iron-carbon composite material for realizing continuous activation of zero-valent aluminum.

[0005] Another purpose of the present invention is to provide the application of an aluminum-iron-carbon composite material for realizing continuous activation of zero-valent aluminum in removing pollutants in wastewater.

[0006] The technical solution adopted by the present invention to achieve the first purpose is: providing a preparation method of an aluminum-iron-carbon composite material for realizing continuous activation of zero-valent aluminum, including the following steps: putting activated carbon, aluminum powder, iron powder, and ball milling beads into a ball milling tank, evacuating and sealing it, and then performing ball milling treatment under an inert atmosphere to obtain the aluminum-iron-carbon composite material.

[0007] The preparation method of the aluminum-iron-carbon composite material provided by the present invention utilizes the synergistic effect of aluminum, iron, and carbon three materials, and adopts the process of ball milling treatment to achieve the de-passivation of aluminum metal and continuously provide electrons. Among them, the carbon material provides the galvanic cathode effect to ensure the alkaline dissolution of aluminum, and also provides a cathode for highly selectively reducing nitrate to nitrogen. The addition of iron powder can bring the following advantages: First, the hardness of metallic iron is relatively high, which is beneficial to assisting grinding, and friction occurs on the surfaces of both aluminum and iron, destroying the surface oxide film; Second, iron and carbon can also form a corrosion primary battery, which is beneficial to the local alkalinity increase on the surface of activated carbon, promoting the activation of aluminum, and thus promoting the selective reduction of nitrate.

[0008] Further, the activated carbon is selected from one or more combinations of coconut shell activated carbon, wood activated carbon, fruit shell activated carbon, and coal-based activated carbon. Such activated carbon materials have a large specific surface area and rich functional groups.

[0009] Further, the purity of the aluminum powder is 95-99%, and the particle size is 50-2000 mesh. The purity of the iron powder is 95-99%, and the particle size is 50-1000 mesh. In the present invention, metal powders with too small particle sizes pose risks during storage and transportation, and metal powders with too large particle sizes have a smaller specific surface area and lower reaction activity.

[0010] Further, the mass ratio of the aluminum powder, iron powder, and activated carbon is 1:(0.2-5):(1-10). Among them, the dosage ratio of carbon and aluminum will affect the construction of the primary battery and the formation of local alkalinity; the dosage ratio of aluminum and iron will also affect the local alkalinity and will also have an impact on the initial activity of aluminum. Preferably, the mass ratio of the aluminum powder, iron powder, and activated carbon is 1:(1-5):5. It has been found through research that controlling the raw material ratio within the above range can ensure the activation and continuous dissolution of aluminum in the iron-aluminum-carbon composite material and higher nitrogen selectivity.

[0011] Further, the mass ratio of the ball milling beads to the material dosage is (10-100):1. The material of the ball milling beads is selected from one or more of zirconia, agate, corundum, and stainless steel, and the particle size of the ball milling beads is 6-20 mm.

[0012] In some better implementation modes, the ball milling beads are composed of ball milling beads with particle sizes of 6 mm, 10 mm, and 15 mm respectively according to the quantity ratio of 15:5:1.

[0013] Further, the equipment for the ball milling treatment is a planetary ball mill, the rotation speed of the ball milling treatment is 200-500 rpm, and the time of the ball milling treatment is 1-20 h. Preferably, the rotation speed of the ball milling treatment is 400 rpm, and the time of the ball milling treatment is 3 h.

[0014] Another technical solution adopted to achieve the second objective of the present invention is to provide an application of the aluminum-iron-carbon composite material prepared by the preparation method described in the first objective of the present invention in removing pollutants from wastewater.

[0015] At present, there are two difficulties in the application of aluminum to pollutants in wastewater: First, how to fully remove the oxide film on the surface of aluminum; Second, how to prevent aluminum from undergoing secondary passivation. At present, the application of conventional zero-valent aluminum-based materials in the environmental field only achieves the removal of the oxide film on the aluminum surface through various means and utilizes the initial reaction activity, but the problem of secondary passivation of aluminum has not been solved. Different from this, in the aluminum-iron-carbon composite material prepared by the present invention, the activated aluminum can continuously output electrons during use, thus effectively avoiding the problem of secondary passivation. As shown in Formulas 1-3, when the aluminum-iron-carbon composite material prepared by the present invention is added to the solution, it mainly undergoes a reaction process in two stages:

[0016] First, the activated carbon material has a large specific surface area and electron transfer ability, and can form a microscopic corrosion primary battery with the ball-milled aluminum and iron in an aqueous solution. Aluminum and iron gradually dissolve and release electrons as anodes, and hydrolysis reactions occur on the surface of carbon as the cathode, generating OH - which will cause the pH on the carbon surface to rise, forming a local alkaline environment and constituting the "Galvanic cathode effect". As the local alkalinity increases, the aluminum surface oxide layer gradually dissolves, thus promoting the activation of zero-valent aluminum;

[0017] Second, there is a large potential difference between the activated zero-valent aluminum and carbon, and more OH - will be generated on the surface of the carbon cathode, which can continuously promote the dissolution of aluminum without passivation. Therefore, the aluminum-iron-carbon composite material can efficiently remove pollutants from wastewater.

[0018] Anodic reaction: Al - 3e - = Al 3+ E 0 (Al 3+ / Al) = -1.66V (Formula 1)

[0019] Fe - 2e - = Fe 2+ E 0 (Fe 2+ / Fe) = -0.44V (Formula 2)

[0020] Cathodic reaction: 2H2O + 2e - = H2 + 2OH - (Formula 3)

[0021] Furthermore, the pollutants in the wastewater of the present invention include inorganic pollutants and organic pollutants. Among them, the inorganic pollutants include: nitrates, nitrites, hexavalent chromium, perchlorates, bromates, selenates, etc.; the organic pollutants include: trichloroethylene, tetrachloroethylene, triclosan, chlorophenol, p-nitrophenol, etc. The pH of the wastewater containing pollutants is 3 to 11, and the removal effect can be exerted within a relatively wide pH range.

[0022] Furthermore, when the aluminum-iron-carbon composite material is used to treat pollutants, the dosage of the aluminum-iron-carbon composite material in the wastewater is 1 to 30 g / L.

[0023] Furthermore, through research, it is found that the activated carbon in the aluminum-iron-carbon composite material has a large specific surface area and abundant functional groups, and has a certain ability to buffer the pH of the solution. At the same time, aluminum and its various hydrolysis products can also play a role in stabilizing the pH of the solution. Therefore, when using this material to treat pollutants, the pH of the solution can be effectively maintained, preventing the solution from becoming overly alkaline.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] (1) The present invention provides a preparation method of an aluminum-iron-carbon composite material capable of realizing continuous activation of zero-valent aluminum. By ball-milling activated carbon, aluminum powder, and iron powder, an aluminum-iron-carbon composite material is obtained. This preparation method is carried out at normal temperature and pressure, the synthesis process is simple, the reaction conditions are mild, and it is suitable for industrial production. In addition, the carbon material, aluminum powder, and iron powder used can be industrial-grade raw materials, and the materials are inexpensive and easily available, can be used on a large scale, and effectively control the cost of treating wastewater.

[0026] (2) The aluminum-iron-carbon composite material provided by the present invention, when put into wastewater containing pollutants, can utilize the galvanic cathodic effect to form a local alkaline environment to promote the activation of aluminum, and zero-valent aluminum can continuously dissolve without passivation, effectively solving the practical problems in the application of zero-valent aluminum materials in the field of environmental remediation.

[0027] (3) The aluminum-iron-carbon composite material provided by the present invention can adapt to a relatively wide pH range (3 to 11), and can still maintain good activity properties and pollutant removal ability in the presence of dissolved oxygen and various ion interferences. It can achieve good treatment effects on various organic and inorganic pollutants in the wastewater, and is widely applicable to various water body restoration scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a schematic diagram of the principle of removing pollutants in wastewater by the aluminum-iron-carbon composite material capable of realizing continuous activation of zero-valent aluminum provided by the present invention;

[0029] Figure 2 is a micrograph of the aluminum-iron-carbon composite material prepared in Example 1 of the present invention;

[0030] Figure 3 Photographs of the aluminum-iron-carbon composite material prepared in Example 1 of the present invention and the aluminum-carbon material, iron-carbon material, and aluminum-iron material prepared in Comparative Examples 2-4;

[0031] Figure 4 Comparison diagram of the effects of the aluminum-iron-carbon composite material prepared in Example 1 of the present invention and Comparative Examples 1-4 on treating nitrate-containing wastewater;

[0032] Figure 5 Comparison diagram of the effects of the aluminum-iron-carbon composite materials prepared in Examples 2-4 of the present invention on treating nitrate-containing wastewater;

[0033] Figure 6 Comparison diagram of the reduction capabilities of the aluminum-iron-carbon composite material prepared in Example 2 of the present invention and the materials prepared in Comparative Examples 1-4; (a) is the graph of the bromate removal rate varying with time; (b) is the graph of the bromide ion concentration varying with time;

[0034] Figure 7 Graph of the removal rate of organic pollutant TCE varying with time when treated with the aluminum-iron-carbon composite material prepared in Example 1 of the present invention;

[0035] Figure 8 Comparison diagram of the effects of the aluminum-iron-carbon composite material prepared in Example 2 of the present invention on treating nitrate-containing wastewater under different pH conditions. Detailed implementation manners

[0036] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0038] The present invention will be further described below in conjunction with specific embodiments, but it is not limited to the present invention.

[0039] Table 1

[0040]

[0041]

[0042] Among the raw materials in the above table, the particle size of the aluminum powder is 80-150 μm and the purity is 99%; the particle size of the iron powder is 10-100 μm and the purity is 98%.

[0043] Example 1

[0044] Add a total of 70 g of agate beads to a 100 mL stainless steel ball milling tank, and add ball milling beads with diameters of 15 mm, 10 mm, and 6 mm in a number ratio of 1:5:15; weigh 2.5 g of coconut shell activated carbon, 0.5 g of aluminum powder, and 0.5 g of iron powder into the ball milling tank respectively, that is, the mass ratio between aluminum, iron, and carbon is 1:1:5, and the mass ratio of the added materials to the ball milling beads is 1:20. After evacuating and sealing the ball milling tank, introduce argon as the protective gas, place the ball milling tank in a planetary ball mill, set the rotation speed to 400 rpm, and continuously ball mill for 3 h. After ball milling, take out the obtained aluminum-iron-carbon composite material and place it under nitrogen protection.

[0045] As Figure 2 shown, the microscopic morphology and energy spectrum analysis of the aluminum-iron-carbon composite material show that the aluminum and iron metal components are well dispersed inside the activated carbon. The particle size of the iron after ball milling is between 10 - 80 μm, and the particle size of the aluminum is between 10 - 50 μm.

[0046] Example 2

[0047] On the basis of Example 1, prepare an aluminum-iron-carbon composite material (Al:Fe:AC = 1:3:5) according to the raw material ratio and parameters shown in Table 1, with other conditions unchanged, and store the product in nitrogen.

[0048] Example 3

[0049] On the basis of Example 1, prepare an aluminum-iron-carbon composite material (Al:Fe:AC = 1:5:5) according to the raw material ratio and parameters shown in Table 1, with other conditions unchanged, and store the product in nitrogen.

[0050] Example 4

[0051] On the basis of Example 1, prepare an aluminum-iron-carbon composite material (Al:Fe:AC = 3:1:5) according to the raw material ratio and parameters shown in Table 1, with other conditions unchanged, and store the product in nitrogen.

[0052] Example 5

[0053] On the basis of Example 1, prepare an aluminum-iron-carbon composite material (Al:Fe:AC = 5:1:5) according to the raw material ratio and parameters shown in Table 1, with other conditions unchanged, and store the product in nitrogen.

[0054] Comparative Example 1

[0055] In a 100 mL stainless steel ball milling tank, ball milling beads (agate beads) with diameters of 15 mm, 10 mm, and 6 mm are added in a number ratio of 1:5:15; 2.5 g of coconut shell activated carbon is weighed into the ball milling tank, and the mass ratio of the added materials to the ball milling beads is 1:20. After the ball milling tank is sealed and evacuated, argon is introduced as a protective gas. The ball milling tank is placed in a planetary ball mill, the equipment rotation speed is 400 rpm, and the continuous ball milling time is 3 h. After ball milling, the obtained carbon material is taken out and placed under nitrogen protection.

[0056] Comparative Example 2

[0057] In a 100 mL stainless steel ball milling tank, ball milling beads (agate beads) with diameters of 15 mm, 10 mm, and 6 mm are added in a number ratio of 1:5:15; 2.5 g of coconut shell activated carbon and 0.5 g of aluminum powder are respectively weighed into the ball milling tank, that is, the mass ratio between aluminum and carbon is 1:5, and the mass ratio of the added materials to the ball milling beads is 1:20. After the ball milling tank is sealed and evacuated, argon is introduced as a protective gas. The ball milling tank is placed in a planetary ball mill, the equipment rotation speed is 400 rpm, and the continuous ball milling time is 3 h. After ball milling, the obtained aluminum-carbon material is taken out and placed under nitrogen protection.

[0058] Comparative Example 3

[0059] In a 100 mL stainless steel ball milling tank, ball milling beads (agate beads) with diameters of 15 mm, 10 mm, and 6 mm are added in a number ratio of 1:5:15; 2.5 g of coconut shell activated carbon and 0.5 g of iron powder are respectively weighed into the ball milling tank, that is, the mass ratio between iron and carbon is 1:5, and the mass ratio of the added materials to the ball milling beads is 1:20. After the ball milling tank is sealed and evacuated, argon is introduced as a protective gas. The ball milling tank is placed in a planetary ball mill, the equipment rotation speed is 400 rpm, and the continuous ball milling time is 3 h. After ball milling, the obtained iron-carbon material is taken out and placed under nitrogen protection.

[0060] Comparative Example 4

[0061] In a 100 mL stainless steel ball milling tank, ball milling beads (agate beads) with diameters of 15 mm, 10 mm, and 6 mm are added in a number ratio of 1:5:15; 0.5 g of aluminum powder and 0.5 g of iron powder are respectively weighed into the ball milling tank, that is, the mass ratio between aluminum and iron is 1:1, and the mass ratio of the added materials to the ball milling beads is 1:20. After the ball milling tank is sealed and evacuated, argon is introduced as a protective gas. The ball milling tank is placed in a planetary ball mill, the equipment rotation speed is 400 rpm, and the continuous ball milling time is 3 h. After ball milling, the obtained aluminum-iron material is taken out and placed under nitrogen protection.

[0062] The physical pictures of the products prepared in Example 1 and Comparative Examples 2-4 are as Figure 3As shown. Due to the cold welding effect of zero-valent aluminum, the aluminum-iron sample after ball milling in Comparative Example 4 presented a metallic flake shape, while the carbon-containing materials in Example 1 and Comparative Examples 2 and 3 were more dispersed.

[0063] Performance Test

[0064] (1) NO3 - -N Removal Effect Test

[0065] In multiple serum bottles, 100 mL of simulated wastewater with a NO3 - -N concentration of 30 mg / L was prepared respectively without adjusting the initial pH of the solution (about 6.7). Aluminum-iron-carbon composite materials prepared in Examples 1-5 (dosage: 20 g / L) and carbon, aluminum-carbon, iron-carbon, and aluminum-iron materials prepared in Comparative Examples 1-4 were added to the serum bottles respectively. The dosages of the materials in Comparative Examples 1-4 were the same as the masses of the respective components contained in the aluminum-iron-carbon composite material in Example 1. After sealing the serum bottles, they were placed in a constant temperature water bath oscillator with the temperature set at 25 °C and the rotation speed set at 200 rpm. Samples of 1.5 mL were taken at regular intervals and filtered through a 0.22-micron polyethersulfone filter head. The concentrations of nitrate and nitrite were detected by ion chromatography, and the ammonia nitrogen concentration was detected by ultraviolet spectrophotometer. The results are as Figure 4 and 5 shown.

[0066] It can be seen from Figure 4 that the aluminum-iron-carbon composite material prepared in Example 1 can completely remove 30 mg / L of NO3 - -N within 10 h, and there is an obvious acceleration phenomenon after 6 h of reaction. However, the removal effects of the carbon, aluminum-carbon, iron-carbon, and aluminum-iron materials in Comparative Examples 1-4 are all poor.

[0067] Furthermore, by comparing the removal effects of Example 1 and Comparative Example 2, since iron with higher hardness was not added to the aluminum-carbon material in Comparative Example 2, on the one hand, the friction effect was worse than that of the iron-carbon composite material; on the other hand, for the aluminum-carbon material after ball milling, although aluminum has a certain activity, an oxide film will quickly form on its surface, making it extremely easy to passivate. After passivation of the aluminum in the aluminum-carbon material after the initial reaction, it loses the ability to continue to output electrons, thereby affecting its removal effect on NO3 - -N.

[0068] It can be seen from Figure 5 that the aluminum-iron-carbon composite materials prepared in Examples 2-5 have better nitrate removal effects compared to Comparative Examples 1-4, and Examples 2 (Al:Fe:AC = 1:3:5) and 3 (Al:Fe:AC = 1:5:5) can achieve better removal effects in a shorter time (8 h). In addition, compared with other examples, Example 2 has a faster reaction rate, while Example 3 has a higher nitrogen selectivity.

[0069] (ii) BrO3 - Removal effect test

[0070] Prepare 100 mL of 60 mg / L BrO3 in multiple serum bottles. - Simulated wastewater, without adjusting the initial pH of the solution (about 6.8), the aluminum-iron-carbon composite material prepared in Example 2 (dosage of 2 g / L), and the carbon, aluminum-carbon, iron-carbon and aluminum-iron materials prepared in Comparative Examples 1-4 were added to the serum bottle, and the dosage of the materials in Comparative Examples 1-4 was consistent with the mass of each component contained in the aluminum-iron-carbon composite material in Example 2. The serum bottle was sealed and placed in a constant temperature water bath oscillator, the temperature was set to 25°C, and the speed was set to 200 rpm. 1.5 mL was sampled regularly and filtered with a 0.22 micron polyethersulfone filter head, and the concentrations of bromate and bromide ions were detected by ion chromatography.

[0071] like Figure 6 As shown, the aluminum iron carbon prepared in Example 2 can absorb 60 mg / L BrO3 within 140 min. - The removal rate of the materials was over 95%, while the removal effects of other materials were poor. Figure 6 (b), Br in the solution after treatment in Example 2 - The concentration increases accordingly with time. According to the change in total bromine concentration, 91% of bromate is removed by reduction, which proves the excellent reducing ability of the aluminum-iron-carbon composite material prepared by the present invention.

[0072] (III) Organic pollutant removal capacity test

[0073] 100 mL of 50 mg / L trichloroethylene (TCE) simulated wastewater was prepared, and the initial pH of the solution was not adjusted (about 6.8), and 20 g / L of the aluminum-iron-carbon composite material prepared in Example 1 was added to the serum bottle. The serum bottle was sealed with a polytetrafluoroethylene gasket and placed in a constant temperature water bath oscillator, the temperature was set to 25°C, and the speed was set to 200 rpm. 1.5 mL was sampled regularly and filtered with a 0.22 micron nylon 66 filter head, and the change in TCE concentration was detected by high performance liquid chromatography.

[0074] like Figure 7 As shown, the aluminum-iron-carbon composite material prepared in Example 1 can completely remove 50 mg / L TCE within 20 minutes.

[0075] (IV) Reduction ability test under different pH conditions

[0076] Prepare 100mL of 30mg / L NO3 --N simulated wastewater, using 0.1 M NaOH and 0.1 M H2SO4 to adjust the initial pH of the solution to 3, 5, 9, and 11 respectively. Add 20 g / L of the aluminum-iron-carbon composite material (Al:Fe:AC = 1:3:5) prepared in Example 2 to the serum bottle. Place the serum bottle in a constant temperature water bath oscillator, set the temperature to 25 °C, and the rotation speed to 200 rpm. Take 1.5 mL of samples at regular intervals and filter them with a 0.22-micron polyethersulfone filter head. Detect the concentrations of nitrate and nitrite by ion chromatography, and detect the ammonia nitrogen concentration by ultraviolet spectrophotometer.

[0077] As Figure 8 shown, the aluminum-iron-carbon composite material prepared in Example 2 has a removal rate of more than 85% for 30 mg / L of NO3 - -N within 10 h when the initial pH of the solution is between 3 and 11; and reaches a removal rate of 100% within 9 h when the pH is between 5 and 9, and the nitrogen selectivity exceeds 70%. Further, when the solution pH increases to 11, the nitrogen selectivity exceeds 80%.

[0078] The above are only preferred embodiments of the present invention, and do not limit the implementation manners and protection scope of the present invention. For those skilled in the art, it should be realized that any equivalent substitution and obvious changes made by using the content of the specification of the present invention should be included in the protection scope of the present invention.

Claims

1. A preparation method of an aluminum-iron-carbon composite material for realizing continuous activation of zero-valent aluminum, comprising the following steps: Aluminum powder, iron powder, and activated carbon are placed in a ball milling tank with a mass ratio of 1:(0.2 - 5):(1 - 10) and ball milling beads. After sealing and evacuating, an inert gas is filled. Ball milling treatment is carried out under an inert atmosphere to obtain an aluminum-iron-carbon composite material.

2. The preparation method according to claim 1, characterized in that, The activated carbon is selected from one or a combination of more of coconut shell activated carbon, wood activated carbon, fruit shell activated carbon, and coal-based activated carbon.

3. The preparation method according to claim 1, characterized in that, The purity of the aluminum powder is 95 - 99%, and the particle size is 50 - 2000 mesh.

4. The preparation method according to claim 1, characterized in that, The purity of the iron powder is 95 - 99%, and the particle size is 50 - 1000 mesh.

5. The preparation method according to claim 1, characterized in that, The mass ratio of the ball milling beads to the material dosage is (10 - 100):

1.

6. The preparation method according to claim 5, characterized in that, The ball milling beads are composed of ball milling beads with particle sizes of 6 mm, 10 mm, and 15 mm in a quantity ratio of 15:5:

1.

7. The preparation method according to claim 1, characterized in that, The equipment for the ball milling treatment is a planetary ball mill.

8. The preparation method according to claim 7, characterized in that, The rotation speed of the ball milling treatment is 200 - 500 rpm, and the time of the ball milling treatment is 1 - 20 h.

9. An application of an aluminum-iron-carbon composite material for realizing continuous activation of zero-valent aluminum in removing pollutants from wastewater, characterized in that, The aluminum-iron-carbon composite material is prepared by the preparation method according to any one of claims 1 - 8; the dosage of the aluminum-iron-carbon composite material in wastewater is 1 - 30 g / L.

Images