A method for preparing aluminum sulfide

Abstract

The present invention relates to the field of chemical synthesis technology, and specifically to a preparation method of aluminum sulfide. The method comprises the following steps: S1, mixing lead sulfide and aluminum powder to obtain a mixture; S2, wrapping and compacting the mixture with an iron sheet, roasting at a temperature of 600-800 °C for 3-8 h, and cooling to room temperature to obtain an intermediate powder; S3, screening the intermediate powder to obtain a primary clinker; S4, roasting the primary clinker at a temperature of 860-950 °C for 3-8 h, and cooling to room temperature to obtain aluminum sulfide powder. The problems in the existing preparation method of lead sulfide, such as violent reaction during the preparation process, generation of toxic gases, and inability to separate the product from the raw materials, are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical synthesis, and specifically relates to a preparation method of aluminum sulfide. Background Art

[0002] Aluminum sulfide is a gray solid inorganic compound, which has high electrochemical activity, high specific surface area and conductivity, low decomposition potential, high energy density and other characteristics, and has very wide applications in supercapacitors, graphene oxide, secondary lithium batteries, preparation of metal and alloy compounds, etc.

[0003] At present, the preparation methods of aluminum sulfide include: obtaining it by igniting a mixture of sulfur powder and aluminum powder in a large crucible with a magnesium strip. However, the reaction of igniting sulfur powder and aluminum powder with a magnesium strip to prepare aluminum sulfide is violent and has a potential explosion risk. Obtaining it by heating dry hydrogen sulfide introduced into a vacuum furnace containing aluminum powder. However, the preparation of aluminum sulfide from dry hydrogen sulfide and aluminum powder causes serious environmental pollution, has a long preparation period, high requirements for equipment, and at the same time hydrogen sulfide is highly toxic. Loutfy et al. (U.S. Patent: 4265716) prepared aluminum sulfide at 1200 °C using pure carbon powder, sulfur powder and alumina powder. Huda et al. prepared aluminum sulfide by the carbothermal sulfidation reaction of alumina at 1200 - 1800 °C. The above two preparation methods both have the disadvantages of too high preparation temperature, generation of greenhouse gases such as CS2, inability to separate the preparation product from the raw materials, and low conversion rate of alumina. Hsu et al. prepared aluminum sulfide using COS and alumina at 850 °C. The preparation temperature of this preparation method is lower than the previous two, but the COS used in the preparation is very unfriendly to the environment, the preparation product cannot be separated from the raw materials, and only 40% of the alumina is converted into aluminum sulfide, with extremely high requirements for equipment. Summary of the Invention

[0004] (I) Technical Problems to be Solved

[0005] In view of the above-mentioned disadvantages and deficiencies of the prior art, the present invention provides a preparation method of aluminum sulfide, which solves the problems of violent reaction, generation of toxic gases, inability to separate the product from the raw materials, etc. in the existing preparation methods of lead sulfide.

[0006] (II) Technical Solutions

[0007] In order to achieve the above purpose, the main technical solutions adopted by the present invention include:

[0008] A preparation method of aluminum sulfide includes the following steps:

[0009] S1. Mix lead sulfide and aluminum powder to obtain a mixture;

[0010] S2. Wrap and compact the mixture with an iron sheet, roast it at a temperature of 600 - 800 °C for 3 - 8 h, and cool it to room temperature to obtain an intermediate powder;

[0011] S3. Screen the intermediate powder to obtain primary clinker;

[0012] S4. Calcinate the primary clinker at a temperature of 860 - 950 °C for 3 - 8 h, and obtain aluminum sulfide powder after cooling to room temperature.

[0013] Furthermore, in step S1, the molar ratio of lead sulfide to aluminum powder is 2 - 4:2.

[0014] Furthermore, in step S2, calcinate at a temperature of 600 °C for 6 h.

[0015] Furthermore, in step S4, calcinate at a temperature of 950 °C for 5 h.

[0016] Furthermore, in step S1, the molar ratio of lead sulfide to aluminum powder is 1:1.

[0017] Furthermore, step S2 is carried out in vacuum or argon.

[0018] Furthermore, step S4 is carried out in vacuum or argon.

[0019] Furthermore, the vacuum degree of the vacuum is 0.09 - 0.1 MPa.

[0020] Furthermore, the vacuum degree of the vacuum is 0.1 MPa.

[0021] The present invention also provides an aluminum sulfide prepared by the preparation method of any of the above technical solutions.

[0022] (III) Beneficial effects

[0023] The aluminum sulfide preparation method provided by the present invention uses lead sulfide and aluminum powder as raw materials and iron as a catalyst. The preparation method is simple, the raw materials are easy to obtain, and it is easy to realize industrial production.

[0024] The reaction during the preparation process is not violent, safe and controllable, and there is no explosion risk. At the same time, no tail gas is generated and no toxic gas is involved during the preparation process.

[0025] The prepared product is easy to separate from the raw materials, the catalyst and impurities. Brief description of the drawings

[0026] Figure 1 is the process flow chart of the preparation method of aluminum sulfide proposed by the present invention;

[0027] Figure 2 is the XRD pattern of the primary clinker in Example 1 of the present invention;

[0028] Figure 3 is the XRD pattern of the aluminum sulfide powder in Example 1 of the present invention. Detailed description of the invention

[0029] The following are specific embodiments of the present invention, and the technical solutions of the present invention are further described in conjunction with the accompanying drawings, but the present invention is not limited to these embodiments.

[0030] The process flow chart of the aluminum sulfide preparation method provided by the present invention is as follows Figure 1 As shown, the specific steps include:

[0031] S1, mixing lead sulfide and aluminum powder to obtain a mixture;

[0032] S2, wrapping and compacting the mixture with iron sheets, calcining at a temperature of 600-800° C. for 3-8 hours, and cooling to room temperature to obtain an intermediate powder;

[0033] S3, sieving the intermediate powder to obtain primary clinker;

[0034] S4. calcine the primary clinker at 860-960° C. for 3-8 h, and obtain aluminum sulfide powder after cooling to room temperature.

[0035] In the above preparation method, lead sulfide and aluminum powder are used as raw materials, iron is used as a catalyst, and the reaction principle is shown in formula (1):

[0036]

[0037] Specifically, in step S1, lead sulfide and aluminum powder are placed in a mixer and mixed to obtain a mixture. Preferably, the aluminum powder is weighed in a glove box filled with high-purity argon and free of water.

[0038] In step S2, an iron sheet is placed along the inner wall of the crucible, the mixture is loaded into the crucible containing the iron sheet, the mixture is wrapped and compacted with the iron sheet, and the mixture is roasted at a temperature of 500 to 800° C. for 3 to 8 hours, and after cooling to room temperature, an intermediate powder and an iron sheet coated with lead are obtained. At this time, the intermediate powder includes lead sulfide, aluminum sulfide, aluminum, and lead, wherein aluminum and lead are mostly in the form of small spheres, and a small part is aggregated into blocks or irregular shapes.

[0039] S3, the intermediate powder is screened by a mechanical separation method to obtain a primary clinker, and the lead-coated iron sheet is vibrated and separated to obtain lead and iron sheet. Specifically, the intermediate powder and the lead-coated iron sheet are poured into a mortar in a fume hood, the lead-coated iron sheet is taken out with tweezers, and the lead and iron sheet are vibrated and separated, and the remaining intermediate powder is screened by a mechanical separation method to remove aluminum and lead to obtain a primary clinker. At this time, the primary clinker includes lead sulfide, aluminum sulfide and a small amount of aluminum.

[0040] S4. The primary clinker is loaded into a crucible, and roasted at 860-960°C for 3-8h to remove impurities. After cooling to room temperature, the crucible is placed in a fume hood and ground to obtain aluminum sulfide powder.

[0041] To better understand the above solution, the exemplary embodiments of the present invention will be described in more detail below through specific examples.

[0042] Example 1

[0043] The preparation method of lead sulfide provided in this example includes the following steps:

[0044] S1. Put 0.2 mol of lead sulfide and 0.2 mol of aluminum powder into a mixer and mix them evenly to obtain a mixed material.

[0045] S2. Place the iron sheet along the inner wall of the graphite crucible, put the mixed material into the graphite crucible containing the iron sheet, use the iron sheet to wrap and compact the mixed material, and calcine it at a temperature of 600 °C for 6 h under a vacuum condition with a vacuum degree of 0.09 MPa. After cooling to room temperature, intermediate powder and an iron sheet coated with lead are obtained.

[0046] S3. Place the graphite crucible in a fume hood, pour the intermediate powder and the iron sheet coated with lead into a mortar, take out the iron sheet coated with lead with tweezers, oscillate and separate to obtain lead and the iron sheet, and use a mechanical separation method to screen the remaining intermediate powder to remove aluminum and lead to obtain primary clinker. The XRD pattern of the primary clinker is as Figure 2 shown.

[0047] S4. Place the primary clinker in a vacuum furnace and calcine it at a temperature of 950 °C for 5 h under a vacuum condition with a vacuum degree of 0.1 MPa. After cooling to room temperature, place the graphite crucible in a fume hood and grind it to obtain aluminum sulfide powder. The XRD pattern of the obtained aluminum sulfide powder is as Figure 3 shown.

[0048] Example 2

[0049] The difference from Example 1 is that in step S1 of this Example 2, 0.4 mol of lead sulfide and 0.2 mol of aluminum powder are put into a mixer and mixed evenly to obtain a mixed material. In step S2, an iron crucible is selected instead of a graphite crucible, and it is calcined at a temperature of 700 °C for 4 h under a vacuum condition with a vacuum degree of 0.09 MPa. After cooling to room temperature, intermediate powder and an iron sheet coated with lead are obtained. In step S4, it is calcined at a temperature of 860 °C for 7 h under a vacuum condition with a vacuum degree of 0.09 MPa to obtain aluminum sulfide powder.

[0050] Others are the same as those in Example 1 and will not be elaborated here.

[0051] Example 3

[0052] It is different from Example 1. In step S1 of this Example 3, 0.3 mol of lead sulfide and 0.2 mol of aluminum powder are placed in a mixer and mixed evenly to obtain a mixed material. In step S2, under an argon atmosphere, it is calcined at a temperature of 600 °C for 8 h, and after cooling to room temperature, an intermediate powder and iron sheets coated with lead are obtained. In step S4, under a vacuum condition with a vacuum degree of 0.09 MPa, it is calcined at a temperature of 870 °C for 6 h to obtain aluminum sulfide powder.

[0053] Others are the same as those in Example 1 and will not be elaborated here.

[0054] Example 4

[0055] It is different from Example 1. In step S1 of this Example 4, 0.4 mol of lead sulfide and 0.2 mol of aluminum powder are placed in a mixer and mixed evenly to obtain a mixed material. In step S2, a corundum crucible is selected to replace the graphite crucible, and under a vacuum condition with a vacuum degree of 0.1 MPa, it is calcined at a temperature of 800 °C for 3 h, and after cooling to room temperature, an intermediate powder and iron sheets coated with lead are obtained.

[0056] Others are the same as those in Example 1 and will not be elaborated here.

[0057] Example 5

[0058] It is different from Example 1. In step S2 of this Example 5, a nickel crucible is selected to replace the graphite crucible, and under a vacuum condition with a vacuum degree of 0.09 MPa, it is calcined at a temperature of 600 °C for 8 h, and after cooling to room temperature, an intermediate powder and iron sheets coated with lead are obtained. In step S4, under a vacuum condition with a vacuum degree of 0.1 MPa, it is calcined at a temperature of 950 °C for 7 h to obtain aluminum sulfide powder.

[0059] Others are the same as those in Example 1 and will not be elaborated here.

[0060] Example 6

[0061] It is different from Example 1. In step S2 of this Example 6, under an argon atmosphere, it is calcined at a temperature of 600 °C for 6 h, and after cooling to room temperature, an intermediate powder and iron sheets coated with lead are obtained. In step S4, under a vacuum condition with a vacuum degree of 0.1 MPa, it is calcined at a temperature of 890 °C for 5 h to obtain aluminum sulfide powder.

[0062] Others are the same as those in Example 1 and will not be elaborated here.

[0063] Example 7

[0064] It is different from Example 1 in that in this Example 7, in step S2, it is calcined at a temperature of 600 °C for 6 h under an argon atmosphere, and after cooling to room temperature, an intermediate powder and an iron sheet coated with lead are obtained. In step S4, it is calcined at a temperature of 920 °C for 6 h under a vacuum condition with a vacuum degree of 0.1 MPa to obtain aluminum sulfide powder.

[0065] Others are the same as in Example 1 and will not be elaborated here.

[0066] It should be understood that the uses of these examples are only for illustrating the present invention rather than intending to limit the protection scope of the present invention. In addition, it should also be understood that after reading the technical content of the present invention, those skilled in the art can make various changes, modifications and / or variations to the present invention, and all these equivalent forms also fall within the protection scope defined by the appended claims of this application.

Claims

1. A method for preparing aluminum sulfide, characterized in that, The preparation method comprises the following steps: S1. Mix lead sulfide and aluminum powder to obtain a mixture; S2. Wrap the mixture with an iron sheet and compact it, then roast it at a temperature of 600 - 800 °C for 3 - 8 h, and after cooling to room temperature, obtain intermediate powder, which includes lead sulfide, aluminum sulfide, aluminum, and lead; S3. Screen the intermediate powder to obtain primary clinker, which includes lead sulfide, aluminum sulfide, and a small amount of aluminum; S4. Roast the primary clinker at a temperature of 860 - 950 °C for 3 - 8 h, and after cooling to room temperature, obtain aluminum sulfide powder.

2. The preparation method of aluminum sulfide according to claim 1, characterized in that, In step S1, the molar ratio of lead sulfide to aluminum powder is 2 - 4:

2.

3. The preparation method of aluminum sulfide according to claim 2, characterized in that, In step S2, roast it at a temperature of 600 °C for 6 h.

4. The preparation method of aluminum sulfide according to claim 3, characterized in that, In step S4, roast it at a temperature of 950 °C for 5 h.

5. The preparation method of aluminum sulfide according to claim 4, characterized in that, In step S1, the molar ratio of lead sulfide to aluminum powder is 1:

1.

6. The preparation method of aluminum sulfide according to claim 5, characterized in that, Step S2 is carried out in vacuum or argon.

7. The preparation method of aluminum sulfide according to claim 6, wherein, Step S4 is carried out in vacuum or argon.

8. The preparation method of aluminum sulfide according to claim 7, characterized in that, The vacuum degree of the vacuum is 0.09 - 0.1 MPa.

9. The preparation method of aluminum sulfide according to claim 8, characterized in that, The vacuum degree of the vacuum is 0.1 MPa.

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