Aluminum alloy magnesium removal agent, preparation method and application thereof and aluminum alloy

Abstract

The invention provides an aluminum alloy magnesium removal agent, a preparation method and application thereof and an aluminum alloy. The aluminum alloy magnesium removal agent comprises a shell and powder wrapped by the shell, the powder comprises at least one of manganese chloride and aluminum fluoride, and the shell breaks in aluminum alloy melt. Therefore, the aluminum alloy magnesium removal agent is placed in an aluminum alloy melt, along with continuous heating of the aluminum alloy melt and continuous increase of the pressure in the shell of the magnesium removal agent, a pressure difference exists between the interior and the exterior of the shell, when the pressure in the shell reaches a certain degree, the shell is broken and even exploded, powder in the shell is diffused all around, and the magnesium removal effect is achieved. And in the shell breaking process, the action area of the powder can be increased, so that the powder is in full contact with the aluminum alloy melt, the reaction is relatively complete, the utilization rate of the magnesium removal agent is greatly improved, and the magnesium removal effect of the aluminum alloy is improved.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloys, and in particular to an aluminum alloy magnesium remover, a preparation method and application thereof, and an aluminum alloy. Background Art

[0002] Aluminum is one of the most effective renewable and recyclable metals. Compared with the production of primary aluminum, the smelting or recycling of scrap aluminum can not only reduce a large amount of energy and water consumption, but also reduce the emission of greenhouse gases and waste slag. However, the raw materials of scrap aluminum are complex, and different types of scrap metal devices are often mixed with a variety of metals, which makes the content of some metal elements in the recycled aluminum components too high and affects its use. Therefore, when smelting recycled aluminum alloys, measures need to be taken to reduce the content of certain metal elements, such as the removal of Mg. However, the current method of removing magnesium has a poor effect on the removal of magnesium, resulting in a high magnesium content in the aluminum alloy after magnesium removal, which affects the performance of the aluminum alloy. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one object of the present invention is to provide an aluminum alloy magnesium remover, which can effectively remove the magnesium element in the aluminum alloy.

[0004] In one aspect of the present invention, the present invention provides an aluminum alloy demagnesizing agent. According to an embodiment of the present invention, the aluminum alloy demagnesizing agent comprises: a shell and a powder wrapped by the shell, the powder comprises at least one of manganese chloride and aluminum fluoride, and the shell ruptures in the aluminum alloy melt. Thus, the aluminum alloy demagnesizing agent is placed in the aluminum alloy melt. As the aluminum alloy melt is continuously heated, the pressure in the shell of the demagnesizing agent continues to increase, so that there is a pressure difference between the inside and outside of the shell. When the pressure inside the shell reaches a certain level, the shell ruptures or even explodes, so that the powder inside the shell diffuses to the surroundings. In addition, in the process of the shell rupture, the effective area of ​​the powder can be increased, so that the powder is fully in contact with the aluminum alloy melt, and the reaction is relatively complete, which greatly improves the utilization rate of the demagnesizing agent and improves the demagnesizing effect of the aluminum alloy.

[0005] Furthermore, the shell is calcium carbonate.

[0006] Furthermore, the particle size of the shell is 2.0 to 3.0 cm, and the shell thickness is 0.6 to 1.0 cm.

[0007] Furthermore, the mass ratio of the manganese chloride to the aluminum fluoride is 1:5 to 5:1.

[0008] Furthermore, the difference between the density of the powder and the density of the aluminum alloy melt is less than or equal to 0.3 g / cm 3 .

[0009] Furthermore, for the aluminum alloy magnesium remover particles, the mass ratio of the powder to the shell is 5:1 to 1:1.

[0010] In another aspect of the present invention, the present invention provides a method for preparing the aluminum alloy demagnesizing agent described above. According to an embodiment of the present invention, the method for preparing the aluminum alloy demagnesizing agent comprises: providing manganese chloride powder and aluminum fluoride powder respectively, and uniformly mixing the manganese chloride powder and the aluminum fluoride powder to obtain a powder; and wrapping the powder with a shell. Thus, the aluminum alloy demagnesizing agent is placed in an aluminum alloy melt. As the aluminum alloy melt is continuously heated, the pressure inside the shell of the demagnesizing agent continues to increase, so that there is a pressure difference between the inside and outside of the shell. When the pressure inside the shell reaches a certain level, the shell ruptures or even explodes, so that the powder inside the shell diffuses to the surroundings. In addition, in the process of the shell rupture, the effective area of ​​the powder can be increased, so that the powder is fully in contact with the aluminum alloy melt, and the reaction is relatively complete, which greatly improves the utilization rate of the demagnesizing agent and improves the demagnesizing effect of the aluminum alloy.

[0011] Furthermore, the method for preparing the manganese chloride powder includes: reacting rhodochrosite with hydrochloric acid to obtain a first mixed solution; adjusting the pH of the first mixed solution to 4-5 to obtain a second mixed solution; sequentially adding hydrogen peroxide and manganese sulfate to the second mixed solution to obtain a third mixed solution; and obtaining the manganese chloride powder by evaporating, concentrating and crystallizing the third mixed solution.

[0012] Furthermore, the method for preparing the aluminum fluoride powder includes: reacting ammonium bicarbonate with fluorosilicic acid to obtain an ammonium fluoride solution and a silicon dioxide precipitate, and separating the ammonium fluoride solution and the silicon dioxide precipitate; reacting the separated ammonium fluoride solution with an aluminum chloride solution to obtain a fourth mixed solution; and obtaining the aluminum fluoride powder by crystallizing, drying, calcining, and crushing the fourth mixed solution.

[0013] In another aspect of the present invention, the present invention provides a method for removing magnesium from an aluminum alloy using the aluminum alloy remover as described above. According to an embodiment of the present invention, the method for removing magnesium from an aluminum alloy using a magnesium remover comprises: melting the aluminum alloy to obtain an aluminum alloy melt, and adding the aluminum alloy remover to the aluminum alloy melt; in the process of continuously heating the aluminum alloy melt, the shell of the aluminum alloy remover ruptures, and the powder in the aluminum alloy remover mixes into the aluminum alloy melt to generate bubbles and magnesium-containing precipitates; the magnesium-containing precipitates are discharged from the aluminum alloy melt as the bubbles escape. Therefore, the above-mentioned method for removing magnesium is simple and easy to implement, and the magnesium remover can be more fully in contact with the aluminum alloy melt, so as to achieve a highly efficient magnesium removal effect, and can effectively and greatly reduce the magnesium content in the aluminum alloy.

[0014] Furthermore, the mass of the aluminum alloy magnesium remover added is 3% to 8% of the mass of the aluminum alloy.

[0015] In another aspect of the present invention, the present invention provides an aluminum alloy obtained by removing magnesium using the above method. According to an embodiment of the present invention, the magnesium content in the aluminum alloy is less than or equal to 0.5%. It can be seen that after removing magnesium using the magnesium removal agent of the present invention, the content of magnesium in the aluminum alloy can be effectively reduced to obtain an aluminum alloy with a low magnesium content. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0017] Figure 1 It is a schematic diagram of the structure of an aluminum alloy magnesium remover in one embodiment of the present invention. DETAILED DESCRIPTION

[0018] The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0019] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0020] In one aspect of the present invention, the present invention provides an aluminum alloy magnesium removal agent. According to an embodiment of the present invention, referring to Figure 1 The aluminum alloy demagnesizing agent comprises: a shell 1 and a powder 2 wrapped by the shell 1, the powder 2 comprises at least one of manganese chloride and aluminum fluoride, and the shell breaks in the aluminum alloy melt. Thus, the aluminum alloy demagnesizing agent is placed in the aluminum alloy melt. As the aluminum alloy melt is continuously heated, the pressure in the shell of the demagnesizing agent continues to increase, so that there is a pressure difference between the inside and outside of the shell. When the pressure inside the shell reaches a certain level, the shell breaks or even explodes, so that the powder inside the shell spreads to the surroundings. In addition, in the process of the shell breaking, the effective area of ​​the powder can be increased, so that the powder is fully in contact with the aluminum alloy melt, and the reaction is relatively complete, which greatly improves the utilization rate of the demagnesizing agent and improves the demagnesizing effect of the aluminum alloy.

[0021] According to an embodiment of the present invention, the principle of removing magnesium from aluminum alloy by a magnesium remover is as follows: when MnCl2 powder in the powder reacts with Mg in the aluminum alloy melt to generate MgCl2 precipitate (displacement reaction of manganese chloride and metallic magnesium), and reacts with Al to generate AlCl3 bubbles (displacement reaction of manganese chloride and metallic aluminum), since MgCl2 has a relatively small density, it is easy to float and adsorb on the surface of AlCl3 bubbles, and the MgCl2 precipitate is removed from the aluminum alloy melt as the AlCl3 bubbles escape, thereby achieving the purpose of removing magnesium, and the manganese element generated by the substitution can be retained in the aluminum alloy as a doping element of the aluminum alloy; when AlF3 powder in the powder reacts with the aluminum alloy melt, AlF3 bubbles and MgF2 precipitate are generated (magnesium ions combine with fluorine ions to generate precipitates, and AlF3 is dispersed in the aluminum alloy melt and in the environment where the substitution reaction of manganese chloride and metallic magnesium generates AlCl3 bubbles, and changes from solid to gas), MgF2 is adsorbed on the surface of AlF3 bubbles, and MgF2 is removed from the aluminum alloy melt by the escape of AlF3 bubbles, thereby achieving the purpose of removing magnesium. It can be seen that both components of the powder can generate gas, which helps the solid reaction products MgCl2 and MgF2 to quickly float out of the aluminum alloy melt, and to a certain extent promotes the magnesium removal reaction; and when the powder includes both manganese chloride and aluminum fluoride powders, it can have a more efficient magnesium removal effect.

[0022] In some embodiments of the present invention, the shell 1 is made of calcium carbonate. Therefore, the shell made of calcium carbonate has a high boiling point and will not undergo phase change in the aluminum alloy melt, that is, it will remain in a solid state, so the calcium carbonate shell can finally be precipitated out of the aluminum alloy melt, so the broken shell will not be mixed in the aluminum alloy melt and pollute the aluminum alloy.

[0023] In some embodiments of the present invention, the particle size of the shell is 2.0-3.0 cm, such as 2.0 cm, 2.1 cm, 2.2 cm, 2.3 cm, 2.4 cm, 2.5 cm, 2.6 cm, 2.7 cm, 2.8 cm, 2.9 cm, 3.0 cm, etc., and the shell thickness is 0.6-1.0 cm, such as 0.6 cm, 0.7 cm, 0.8 cm, 0.9 cm, 1.0 cm, etc. The aluminum alloy magnesium removal agent of the above size is convenient for it to be more evenly dispersed in the aluminum alloy liquid and is not easy to agglomerate.

[0024] In some embodiments of the present invention, the mass ratio of manganese chloride to aluminum fluoride is 1:5 to 5:1, for example, the mass ratio of manganese chloride to aluminum fluoride is 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, etc. The above ratio of manganese chloride to aluminum fluoride can more efficiently remove magnesium from aluminum alloys.

[0025] In some embodiments of the present invention, the difference between the density of the powder and the density of the aluminum alloy melt is less than or equal to 0.3 g / cm3 As a result, the density of the powder is comparable to that of the aluminum alloy melt, so the powder is not easy to float or sink when added into the aluminum alloy melt, making the powder reaction more thorough, which in turn helps to improve the magnesium removal efficiency.

[0026] In some embodiments of the present invention, for the aluminum alloy magnesium removal agent particles, the mass ratio of the powder to the shell is 5:1 to 1:1, such as 1:1, 2:1, 3:1, 4:1, 5:1, etc. In this way, the ratio of the powder to the shell is appropriate, which helps to control the usage ratio between the magnesium removal agent and the aluminum alloy during magnesium removal, and also helps to evenly distribute the powder in the aluminum alloy liquid, thereby improving the magnesium removal efficiency.

[0027] In the embodiment of the present invention, the mass ratio, density and other parameters of manganese chloride and aluminum fluoride can be adjusted within the above range to obtain an aluminum alloy magnesium removal agent that removes magnesium faster and more efficiently.

[0028] In another aspect of the present invention, the present invention provides a method for preparing the above-mentioned aluminum alloy magnesium removal agent. According to an embodiment of the present invention, the method for preparing the aluminum alloy magnesium removal agent comprises:

[0029] S100: providing manganese chloride powder and aluminum fluoride powder respectively, and uniformly mixing the manganese chloride powder and the aluminum fluoride powder to obtain a powder.

[0030] In some embodiments, manganese chloride powder and aluminum fluoride powder are mixed uniformly in a mass ratio of 1:5 to 5:1, for example, the mass ratio of manganese chloride to aluminum fluoride is 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, etc. The above ratio of manganese chloride and aluminum fluoride can more efficiently remove magnesium from aluminum alloys.

[0031] There are no special requirements for the sources of manganese chloride powder and aluminum fluoride powder, which can be purchased in the market or prepared by themselves. In some embodiments of the present invention, manganese chloride powder and aluminum fluoride powder can be prepared by the following method, which is as follows:

[0032] In some embodiments, the method of preparing manganese chloride powder comprises:

[0033] S1: reacting rhodochrosite with hydrochloric acid to obtain a first mixed solution. The main component of rhodochrosite is manganese carbonate, and it may also contain elements such as iron and calcium. The reaction of rhodochrosite with hydrochloric acid can obtain a first mixed solution containing manganese chloride, calcium chloride and ferric chloride.

[0034] In some embodiments, the mass ratio of rhodochrosite to hydrochloric acid may be 1:3 to ensure sufficient reaction of the rhodochrosite.

[0035] S2: adjusting the pH of the first mixed solution to 4-5 to obtain a second mixed solution.

[0036] In some embodiments, in the step, lime can be added to the first mixed solution to neutralize unreacted hydrochloric acid, thereby obtaining a second mixed solution with a pH of 4 to 5.

[0037] S3: adding hydrogen peroxide and manganese sulfate to the second mixed solution in sequence to obtain a third mixed solution.

[0038] In this step, hydrogen peroxide is first added to the second mixed solution to remove the iron element in the second mixed solution (to generate iron hydroxide precipitation); after the iron element is removed, manganese sulfate is added to the second mixed solution to remove the calcium element (to generate calcium sulfate precipitation), thereby obtaining a preliminarily purified third mixed solution.

[0039] S4: Obtaining manganese chloride powder by evaporating, concentrating and crystallizing the third mixed solution.

[0040] In some specific embodiments, the manganese chloride powder can be obtained by evaporating, filtering, re-evaporating, concentrating, cooling and crystallizing, centrifuging, and crushing the third mixed solution. There are no special requirements for the specific processing conditions, and those skilled in the art can flexibly adjust them according to actual needs.

[0041] In some embodiments, the method of preparing aluminum fluoride powder comprises:

[0042] T1: reacting ammonium bicarbonate with fluorosilicic acid to obtain an ammonium fluoride solution and a silicon dioxide precipitate, and separating the ammonium fluoride solution and the silicon dioxide precipitate.

[0043] T2: reacting the separated ammonium fluoride solution with the aluminum chloride solution to obtain a fourth mixed solution;

[0044] T3: Aluminum fluoride powder is obtained by crystallizing, drying, calcining and pulverizing the fourth mixed solution.

[0045] S200: The powder is encapsulated by a shell.

[0046] In some embodiments, the specific encapsulation method is: mixing powder and calcium carbonate modifier, and calcining at high temperature; during the calcination process, the calcium carbonate and the modifier undergo a solid phase reaction to form a shell, that is, the formed shell encapsulates the powder to obtain the aluminum alloy magnesium removal agent.

[0047] In which, further, the modifier can be a metal modifier, and in some specific embodiments, the modifier is calcium stearate. In some embodiments, the calcination temperature can be 550° C. to 600° C. Under the above conditions, a shell structure that wraps the powder can be effectively obtained.

[0048] According to an embodiment of the present invention, the above method can be used to quickly and efficiently prepare a magnesium remover, and the aluminum alloy magnesium remover is placed in an aluminum alloy melt. As the aluminum alloy melt is continuously heated, the pressure inside the shell of the magnesium remover continues to increase, so that there is a pressure difference between the inside and outside of the shell. When the pressure inside the shell reaches a certain level, the shell ruptures or even explodes, causing the powder inside the shell to diffuse to the surroundings. In addition, during the process of shell rupture, the effective area of ​​the powder can be increased, so that the powder is fully in contact with the aluminum alloy melt, and the reaction is relatively complete, thereby greatly improving the utilization rate of the magnesium remover and improving the magnesium removal effect of the aluminum alloy.

[0049] Among them, when the MnCl2 powder in the powder reacts with Mg in the aluminum alloy melt to generate MgCl2 precipitation (displacement reaction of manganese chloride and metallic magnesium), and reacts with Al to generate AlCl3 bubbles (displacement reaction of manganese chloride and metallic aluminum), due to the small density of MgCl2, it is easy to float and adsorb on the surface of AlCl3 bubbles, and the MgCl2 precipitation is eliminated from the aluminum alloy melt as the AlCl3 bubbles escape, thereby achieving the purpose of removing magnesium, and the manganese element generated by the substitution can be retained in the aluminum alloy as a doping element of the aluminum alloy; when the AlF3 powder in the powder reacts with the aluminum alloy melt, AlF3 bubbles and MgF2 precipitation are generated (magnesium ions and fluorine ions combine to generate precipitation, and AlF3 is dispersed in the aluminum alloy melt and in the environment where the substitution reaction of manganese chloride and metallic magnesium generates AlCl3 bubbles, and changes from solid to gas), MgF2 is adsorbed on the surface of AlF3 bubbles, and MgF2 is eliminated from the aluminum alloy melt by the escape of AlF3 bubbles, thereby achieving the purpose of removing magnesium. It can be seen that both components of the powder can generate gas, which helps the solid reaction products MgCl2 and MgF2 to quickly float out of the aluminum alloy melt, and to a certain extent promotes the magnesium removal reaction; and when the powder includes both manganese chloride and aluminum fluoride powders, it can have a more efficient magnesium removal effect.

[0050] In another aspect of the present invention, the present invention provides a method for removing magnesium from an aluminum alloy using the aluminum alloy magnesium removal agent described above. According to an embodiment of the present invention, the method for removing magnesium from an aluminum alloy using the magnesium removal agent comprises:

[0051] T100: melting the aluminum alloy to obtain an aluminum alloy melt, and adding an aluminum alloy magnesium removal agent to the aluminum alloy melt;

[0052] In some embodiments of the present invention, the difference between the density of the powder in the magnesium removal agent and the density of the aluminum alloy melt is less than or equal to 0.3 g / cm 3 As a result, the density of the powder is comparable to that of the aluminum alloy melt, so the powder is not easy to float or sink when added into the aluminum alloy melt, making the powder reaction more thorough, which in turn helps to improve the magnesium removal efficiency.

[0053] Furthermore, the mass of the added aluminum alloy magnesium remover is 3% to 8% of the mass of the aluminum alloy. In this way, it can be effectively ensured that the magnesium remover can effectively remove the magnesium element in the aluminum alloy to the greatest extent, while ensuring the complete reaction of the powder, and thus will not introduce unreacted manganese chloride powder and aluminum fluoride powder into the aluminum alloy. Among them, the specific mass ratio of the mass of the added aluminum alloy magnesium remover to the aluminum alloy can be flexibly set within the above range according to the magnesium content in the aluminum alloy before magnesium removal. For example, when the aluminum alloy contains a higher content of magnesium, a larger amount of magnesium remover can be added to the aluminum alloy melt. When the aluminum alloy contains a higher content of magnesium, the amount of magnesium remover can be appropriately reduced.

[0054] In some embodiments of the present invention, the specific method of adding the aluminum alloy demagnesizing agent to the aluminum alloy melt may be: the demagnesizing agent may be transported to the middle and bottom of the aluminum alloy melt by external force, and stirring is performed during the reaction.

[0055] T200: During the continuous heating of the aluminum alloy melt, the shell of the aluminum alloy magnesium remover ruptures, and the powder in the aluminum alloy magnesium remover mixes into the aluminum alloy melt, generating bubbles and magnesium-containing precipitates.

[0056] T300: Magnesium-containing precipitates are discharged from the aluminum alloy melt along with the escape of bubbles, obtaining an aluminum alloy with a low magnesium content.

[0057] According to the embodiments of the present invention, the above-mentioned magnesium removal method is simple and easy to implement, and can make the magnesium removal agent more fully contact with the aluminum alloy melt, thereby achieving a highly efficient magnesium removal effect and effectively greatly reducing the magnesium content in the aluminum alloy.

[0058] In some specific embodiments, when MnCl2 powder in the powder reacts with Mg in the aluminum alloy melt to generate MgCl2 precipitate (displacement reaction of manganese chloride and metallic magnesium), and reacts with Al to generate AlCl3 bubbles (displacement reaction of manganese chloride and metallic aluminum), MgCl2 has a relatively small density and is easily floated and adsorbed on the surface of AlCl3 bubbles. The MgCl2 precipitate is removed from the aluminum alloy melt as the AlCl3 bubbles escape, thereby achieving the purpose of removing magnesium, and the manganese element generated by the substitution can be retained in the aluminum alloy as a doping element of the aluminum alloy; when AlF3 powder in the powder reacts with the aluminum alloy melt, AlF3 bubbles and MgF2 precipitate are generated (magnesium ions combine with fluorine ions to generate precipitate, and AlF3 is dispersed in the aluminum alloy melt and in the environment where the substitution reaction of manganese chloride and metallic magnesium generates AlCl3 bubbles, changing from solid to gaseous), the MgF2 precipitate is adsorbed on the surface of the AlF3 bubbles, and the MgF2 precipitate is removed from the aluminum alloy melt by the escape of the AlF3 bubbles, thereby achieving the purpose of removing magnesium. It can be seen that both components of the powder can generate gas, which helps the solid reaction products MgCl2 and MgF2 to quickly float out of the aluminum alloy melt, and to a certain extent promotes the magnesium removal reaction. Of course, those skilled in the art can understand that MgCl2 precipitation may also be removed from the aluminum alloy melt along with the escape of AlF3 bubbles, and MgF2 precipitation may also be removed from the aluminum alloy melt along with the escape of AlCl3 bubbles; and when the powder includes both manganese chloride and aluminum fluoride powders, it can have a more efficient magnesium removal effect.

[0059] In another aspect of the present invention, the present invention provides an aluminum alloy obtained by removing magnesium using the above method. According to an embodiment of the present invention, the magnesium content in the aluminum alloy is less than or equal to 0.5%. It can be seen that after removing magnesium using the magnesium removal agent of the present invention, the content of magnesium in the aluminum alloy can be effectively reduced to obtain an aluminum alloy with a low magnesium content.

[0060] According to an embodiment of the present invention, the magnesium removal agent of the present invention can be applicable to aluminum alloys with a high magnesium content before magnesium removal, for example, the magnesium content in the aluminum alloy before magnesium removal is 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, etc. By using the magnesium removal agent of the present invention, an aluminum alloy with a low magnesium content (the magnesium content in the aluminum alloy is less than or equal to 0.5%) can be obtained from the above-mentioned aluminum alloy with a high magnesium content.

[0061] Example

[0062] Example 1

[0063] Preparation of MnCl2 powder: reacting crushed rhodochrosite with hydrochloric acid, wherein the mass ratio of rhodochrosite to hydrochloric acid is 1:3, and after the reaction is complete, a first mixed solution is obtained; lime is added to the first mixed solution to neutralize the hydrochloric acid, and the pH value is controlled to be 4 to obtain a second mixed solution; hydrogen peroxide is added to the second mixed solution to remove iron; manganese sulfate is added to the second mixed solution to remove calcium, and the solution is purified to obtain a third mixed solution; the third mixed solution is sequentially evaporated, filtered, evaporated and concentrated, cooled and crystallized, centrifuged and crushed to obtain MnCl2 powder.

[0064] Preparation of AlF3 powder: reacting ammonium bicarbonate with fluorosilicic acid to obtain an ammonium fluoride solution and a silicon dioxide precipitate, and separating the ammonium fluoride solution and the silicon dioxide precipitate; evaporating the ammonium fluoride solution and reacting it with an aluminum chloride solution to obtain a fourth mixed solution; and crystallizing, drying, calcining and crushing the fourth mixed solution to obtain AlF3 powder.

[0065] The MnCl2 powder and AlF3 powder prepared above are uniformly mixed to obtain a powder, wherein the mass ratio of MnCl2 to AlF3 is 1:5.

[0066] The mixed powder is encapsulated in a calcium carbonate shell to obtain a magnesium removal agent.

[0067] Example 2

[0068] The difference from Example 1 is that the mass ratio of MnCl2 to AlF3 is 1:2.

[0069] Example 3

[0070] The difference from Example 1 is that the mass ratio of MnCl2 to AlF3 is 1:1.

[0071] Example 4

[0072] The difference from Example 1 is that the mass ratio of MnCl2 to AlF3 is 3:1.

[0073] Example 5

[0074] The difference from Example 1 is that the mass ratio of MnCl2 to AlF3 is 5:1.

[0075] Example 6

[0076] The difference from Example 1 is that the powder only includes MnCl2 powder.

[0077] Example 7

[0078] The difference from Example 1 is that the powder only includes AlF3 powder.

[0079] Comparative Example 1

[0080] The difference from Example 3 is that the magnesium removal agent is only a powder containing MnCl2 powder and AlF3 powder, and is not wrapped in a shell.

[0081] The magnesium removal agent prepared in the above-mentioned Examples 1-7 and Comparative Example 1 was used to remove magnesium from the aluminum alloy, wherein the content of magnesium in the aluminum alloy before magnesium removal was 0.6%, and the mass of the added aluminum alloy magnesium removal agent was 5% of the mass of the aluminum alloy. The magnesium content in the aluminum alloy was detected after magnesium removal, and the test results are shown in Table 1.

[0082] Table 1

[0083]

[0084]

[0085] It can be seen from Table 1 that the magnesium removal agent of the present invention has a good magnesium removal effect, and can control the magnesium content in the aluminum alloy to below 0.5%, thereby obtaining an aluminum alloy with a low magnesium content. It can be seen from Table 1 that as the AlF3 content in the powder increases, the magnesium removal efficiency of the magnesium removal agent increases, and a higher magnesium removal efficiency can be obtained when MnCl2 and AlF3 cooperate with each other. Moreover, by comparing Example 3 with Comparative Example 1, it can be seen that when the magnesium removal agent contains a shell wrapping, it can have a better magnesium removal effect, because when the shell explodes in the aluminum alloy melt, the powder in the shell can be better diffused in the aluminum alloy melt, thereby contributing to the uniform diffusion of the powder and improving the magnesium removal efficiency.

[0086] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0087] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A magnesium remover for aluminum alloy, It is characterized in that include: A shell and a powder wrapped by the shell, wherein the powder comprises at least one of manganese chloride and aluminum fluoride, and the shell is broken in an aluminum alloy melt.

2. The aluminum alloy magnesium remover according to claim 1, It is characterized in that The shell is calcium carbonate.

3. The aluminum alloy magnesium removal agent according to claim 1 or 2, It is characterized in that The particle size of the shell is 2.0-3.0 cm, and the shell thickness is 0.6-1.0 cm.

4. The aluminum alloy magnesium removal agent according to claim 1 or 2, It is characterized in that The mass ratio of the manganese chloride to the aluminum fluoride is 1:5 to 5:

1.

5. The aluminum alloy magnesium remover according to claim 4, It is characterized in that The difference between the density of the powder and the density of the aluminum alloy melt is less than or equal to 0.3 g / cm 3 .

6. The aluminum alloy magnesium removal agent according to claim 1 or 2, It is characterized in that For the aluminum alloy magnesium remover particles, the mass ratio of the powder to the shell is 5:1 to 1:

1.

7. A method for preparing the aluminum alloy magnesium removal agent according to any one of claims 1 to 6, It is characterized in that include: Providing manganese chloride powder and aluminum fluoride powder respectively, and uniformly mixing the manganese chloride powder and the aluminum fluoride powder to obtain a powder; The powder is encapsulated by a shell.

8. The method according to claim 7, It is characterized in that The method for preparing the manganese chloride powder comprises: reacting rhodochrosite with hydrochloric acid to obtain a first mixed solution; Adjusting the pH of the first mixed solution to 4-5 to obtain a second mixed solution; adding hydrogen peroxide and manganese sulfate to the second mixed solution in sequence to obtain a third mixed solution; The manganese chloride powder is obtained by evaporating, concentrating and crystallizing the third mixed solution.

9. The method according to claim 7 or 8, It is characterized in that The method for preparing the aluminum fluoride powder comprises: reacting ammonium bicarbonate with fluorosilicic acid to obtain an ammonium fluoride solution and a silicon dioxide precipitate, and separating the ammonium fluoride solution and the silicon dioxide precipitate; reacting the separated ammonium fluoride solution with the aluminum chloride solution to obtain a fourth mixed solution; The aluminum fluoride powder is obtained by crystallizing, drying, calcining and pulverizing the fourth mixed solution.

10. The method according to claim 7, It is characterized in that The encapsulation method comprises: mixing powder and a calcium carbonate modifier, and calcining at a high temperature; during the calcining process, the calcium carbonate and the modifier undergo a solid phase reaction to form a shell, thereby obtaining the aluminum alloy magnesium removal agent.

11. A method for removing magnesium from an aluminum alloy using the aluminum alloy magnesium remover according to any one of claims 1 to 6, It is characterized in that include: Melting the aluminum alloy to obtain an aluminum alloy melt, and adding the aluminum alloy magnesium removal agent to the aluminum alloy melt; In the process of continuously heating the aluminum alloy melt, the shell of the aluminum alloy magnesium remover is broken, and the powder in the aluminum alloy magnesium remover is mixed into the aluminum alloy melt to generate bubbles and magnesium-containing precipitates; The magnesium-containing precipitate is discharged from the aluminum alloy melt along with the escape of bubbles.

12. The method according to claim 11, It is characterized in that The mass of the added aluminum alloy magnesium remover is 3% to 8% of the mass of the aluminum alloy.

13. An aluminum alloy obtained by removing magnesium using the method according to claim 11 or 12, It is characterized in that The magnesium content in the aluminum alloy is less than or equal to 0.5%.

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