Preparation process of aluminum trichloride

Abstract

The invention discloses a preparation process of aluminum trichloride. The invention provides a preparation method of aluminum trichloride. The preparation method comprises the following steps: (1) providing a dry aluminum source and a carbon source; (2) roasting the dried aluminum source obtained in the step (1) in an inert atmosphere; and (3) the roasted aluminum source obtained in the step (2), the dried carbon source obtained in the step (1) and chlorine are mixed for chlorination to obtain aluminum trichloride, the aluminum source further comprises carbon, and in the dried aluminum source and the dried carbon source, the weight ratio of aluminum to carbon is smaller than or equal to 1: 0.3 on the basis of aluminum oxide and carbon.

Description

Technical Field

[0001] This invention relates to a method for producing aluminum trichloride, specifically to a process for the resource recycling of low-quality aluminum-containing and carbon-containing substances. Background Technology

[0002] Aluminum trichloride is an important inorganic chemical raw material used in the synthesis of dyes, synthetic rubber, pharmaceuticals, fragrances, and many other fields. Simultaneously, as a crucial catalyst, it has limited substitutability, maintaining sustained market demand for a long time. In recent years, the rapid development of industrial production in my country has driven a rapid increase in the demand for aluminum trichloride.

[0003] The aluminum ingot chlorination process is one of the mainstream methods for the industrial production of aluminum trichloride. It requires the electrolysis of alumina into aluminum ingots, and the aluminum ingots are chlorinated at 800-900℃ to obtain aluminum chloride. This process is energy-intensive, and the price of aluminum ingots fluctuates greatly due to the influence of the electrolytic aluminum market, resulting in a low cost advantage.

[0004] Patent CN110589860A reports that aluminum trichloride is prepared by cleaning, crushing, melting, and then chlorinating recycled waste aluminum at high temperature. The separation of inorganic metal impurities is achieved through melting, but the removal of organic impurities is not explained in detail.

[0005] Patent US3760066 reports the preparation of alumina from bauxite by alkaline washing to remove impurities and calcination at different temperatures to remove water. The resulting alumina is then chlorinated at 950-1000℃ to produce aluminum trichloride with a yield of ≥96%, achieving efficient aluminum recovery. However, this technology suffers from bottlenecks such as long process, limited raw materials, and high energy consumption, which restrict its further development.

[0006] China is the world's largest producer and consumer of aluminum. In 2024, my country's primary aluminum production was 43.38 million tons, and its recycled aluminum production was 10.5 million tons, resulting in an aluminum recycling rate of only 24%. Compared with developed countries (such as Europe and the United States, where the recycling rate of scrap aluminum exceeds 80%), there is still room for improvement in China. Meanwhile, under the goal of carbon neutrality, the recycling of aluminum will become a key development direction.

[0007] There is an urgent need in this field for a method to prepare aluminum trichloride that can recover and reuse low-quality aluminum and carbon sources, produce aluminum trichloride with high yield, high purity and activity, is simple to operate, is easy to industrialize, and can reduce the amount of reducing agent (e.g., carbon-containing substances) used. Summary of the Invention

[0008] One objective of this application is to provide a method for preparing aluminum trichloride, which enables the recycling and reuse of low-quality aluminum and carbon sources, produces aluminum trichloride with high yield, high purity and activity, is simple to operate, and is easy to industrialize, while reducing the amount of reducing agent (e.g., carbon-containing substances) used.

[0009] This application provides a method for preparing aluminum trichloride, comprising the following steps:

[0010] (1) Provide dry aluminum and carbon sources;

[0011] (2) The dried aluminum source obtained in step (1) is calcined under an inert atmosphere;

[0012] (3) The calcined aluminum source obtained in step (2) and the dried carbon source obtained in step (1) are mixed and chlorinated with chlorine gas to obtain aluminum trichloride.

[0013] The aluminum source also includes carbon.

[0014] In the dried aluminum source and dried carbon source, the weight ratio of aluminum to carbon, calculated as alumina and carbon, is ≤1:0.3.

[0015] Another aspect of this application provides aluminum trichloride, which is prepared by the method described in this application, wherein the purity of the aluminum trichloride is ≥98.5% by weight and the total content of metal impurities is ≤0.1% by weight.

[0016] This application's method can react low-quality alumina-containing raw materials such as aluminum ash slag and aluminum trichloride adsorbent with a carbon-containing reducing agent to convert them into high-value aluminum trichloride products. Furthermore, the reducing agent is not limited to solid carbon-containing materials; gaseous carbon-containing reducing media such as carbon monoxide or phosgene synthesis tail gas can also be used, achieving efficient resource recycling while significantly reducing solid waste and harmful gas emissions. This application's method effectively utilizes the embedded carbon source in the aluminum source to achieve atomic-level uniform mixing of carbon and aluminum components, synergistically carrying out high-temperature chlorination, significantly improving the production efficiency and product purity of aluminum trichloride, while effectively reducing the amount of carbon-containing reducing agent used.

[0017] In addition, the method described in this application has advantages such as a simple process, strong operability, and excellent product quality, and is easy to industrialize. Detailed Implementation

[0018] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.

[0019] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0020] The "range" disclosed herein is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also expected. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0021] Unless otherwise specified in this application, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions.

[0022] Unless otherwise specified, all technical features and preferred features mentioned herein can be combined to form new technical solutions.

[0023] In this application, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0024] In this application, unless otherwise specified, the terms "comprising" and "including" as used herein are open-ended or closed-ended. For example, "comprising" and "including" may mean that other components not listed may also be included, or that only the listed components may be included.

[0025] In the description of this article, it should be noted that, unless otherwise stated, "above" and "below" include the number itself, and "several" in "one or more" means two or more.

[0026] In this description, unless otherwise stated, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0027] Unless otherwise specified, percentages (%) or parts refer to weight percentages or parts by weight of the composition.

[0028] Unless otherwise stated herein, the sum of the contents of the components in the composition is 100%.

[0029] Unless otherwise stated herein, the sum of the parts of each component in the composition may be 100 parts by weight.

[0030] In this document, unless otherwise stated, “combination of” means a multi-component mixture of the elements, such as two, three, four, and up to the maximum possible multi-component mixture.

[0031] Unless otherwise specified, the term "a" as used in this specification means "at least one".

[0032] Unless otherwise specified, all methods or steps in this application are performed at room temperature and pressure.

[0033] This application provides a method for preparing aluminum trichloride, comprising the following steps:

[0034] (1) Provide dry aluminum and carbon sources;

[0035] (2) The dried aluminum source obtained in step (1) is calcined under an inert atmosphere;

[0036] (3) The calcined aluminum source obtained in step (2), the dried carbon source obtained in step (1), and chlorine gas are mixed and chlorinated to obtain aluminum trichloride.

[0037] The aluminum source also includes carbon.

[0038] In the dried aluminum source and dried carbon source, the weight ratio of aluminum to carbon, calculated as alumina and carbon, is ≤1:0.3.

[0039] In this application, the aluminum source refers to an aluminum-containing material with an alumina content of ≥50% by weight (e.g., ≥60% by weight, ≥70% by weight, 50-90% by weight, 50-80% by weight). Typically, the aluminum source includes, but is not limited to, one or more of the following: alumina adsorbents, kaolin, alumina powder, bauxite, fly ash, and aluminum slag.

[0040] In this application, the aluminum source also includes carbon. The carbon content, based on the total weight of the aluminum source, is ≥1% by weight, for example ≥3% by weight, ≥5% by weight, 1-30% by weight, 2-25% by weight, 3-20% by weight, or 4-15% by weight.

[0041] In this application, the aluminum source may also contain other substances, such as hydrogen, silicon dioxide, iron, nickel, vanadium, sodium, phosphorus, etc. Typically, other substances account for 0-50% by weight of the total weight of the aluminum source, for example, 0-40% by weight, 0.1-40% by weight, or 1-40% by weight.

[0042] In this application, the carbon source can be a solid carbon source or a gaseous carbon source. Typically, the solid carbon source has a carbon content ≥ 80% by weight (e.g., 80-99% by weight, 85-95% by weight). Non-limiting examples of the solid carbon source may be one or more of petroleum coke, activated carbon, coke, charcoal, and calcined coke. Typically, non-limiting examples of the gaseous carbon source may be one or more of carbon monoxide or phosgene synthesis tail gas.

[0043] In this application, the aluminum source and solid carbon source may be provided in particulate form. Typically, the sieved particle size of the particles is 0.02-1 mm, for example 0.02-0.8 mm, 0.02-0.6 mm, 0.05-0.4 mm, or 0.05-0.2 mm.

[0044] In this application, the weight ratio of aluminum to carbon in the dried aluminum source and the dried carbon source is ≤1:0.3 (e.g., ≤1:0.2), based on alumina and carbon, for example 1:(0.01-0.3), 1:(0.05-0.3), 1:(0.1-0.3), 1:(0.15-0.3), 1:(0.15-0.29), 1:(0.1-0.2).

[0045] In this application, the method for drying the aluminum and carbon sources is a commonly used drying method in the art. For example, the aluminum and carbon sources (in the case of solid carbon sources) can be heated. The heating temperature is typically 50-300°C. When using a gaseous carbon source, dehydration can be achieved through methods such as condensation dehydration or desiccant dehydration. Typically, the moisture content of the dried aluminum and carbon sources is ≤1% by weight, typically ≤0.5% by weight, for example ≤0.1% by weight (e.g., 0.001-1% by weight, 0.05-1% by weight).

[0046] In step (2) above, the roasting temperature is usually 200-800℃, for example 250-700℃, 300-600℃, 300-500℃.

[0047] In step (2) above, the inert atmosphere is usually nitrogen, rare gas or a combination thereof.

[0048] In step (2) above, the roasting time can be 0.5-10h, for example 0.5-5h or 0.5-3h.

[0049] Without being bound by any specific theory, it is believed that through the roasting process, the carbon and aluminum in the aluminum source can achieve atomic-level uniform mixing, which can synergistically carry out high-temperature chlorination, significantly improving the production efficiency and product purity of aluminum trichloride, while greatly reducing the amount of reducing agent (carbon) used.

[0050] In one example of this application, when using a solid carbon source, the solid carbon source can be roasted together with the aluminum source or roasted separately.

[0051] In step (3) of this application, the mixing method can be a method commonly used in the art, including but not limited to stirring. When a solid carbon source is used and co-calcined with an aluminum source, the carbon source and aluminum source are already in a mixed state. When a gaseous carbon source is used, the mixing includes introducing the gaseous carbon source and chlorine together or separately into a reactor containing an aluminum source, or the mixing can also involve adding the aluminum source to a reactor containing chlorine and the gaseous carbon source. When a solid carbon source is used, the solid carbon source and aluminum source are pre-mixed and placed in a reactor, and then chlorine is introduced to achieve mixing; alternatively, the solid carbon source and aluminum source can be added to a reactor containing chlorine.

[0052] The chlorination conditions can be those commonly used in the art. In one example of this application, the chlorination temperature is 300-1500℃, or 400-1200℃, or 500-1200℃, or 600-1200℃; the chlorination time is 1-20h, for example 2-15h, 3-10h, etc.

[0053] In one example of this application, during the chlorination process, chlorine gas is continuously introduced into the reactor at a rate of 10-100 L / h, for example, 20-80 L / h or 25-60 L / h. When using a gaseous carbon source, during the chlorination process, the gaseous carbon source is continuously introduced into the reactor at a rate of 10-30 L / h. Typically, the rate of introduction of the gaseous carbon source can be adjusted based on the required total amount of carbon source to achieve the desired total amount.

[0054] The aluminum trichloride product prepared by the method described in this application is typically a gas. A solid product is usually obtained through condensation. In one example of this application, to improve the purity and production efficiency of the obtained product, multi-stage condensation can be used to collect the aluminum trichloride product, for example, 2-6 stages of condensation. "Multi-stage condensation" means condensing the gaseous product at multiple temperatures from high to low. For example, two-stage condensation means condensation at two temperatures from high to low, three-stage condensation means condensation at three temperatures from high to low, and so on. In one example of this application, the multi-stage condensation is 2-4 stages, for example, three stages. In a preferred embodiment of this application, the three condensation temperatures from high to low in the three-stage condensation are 200-230°C (e.g., 200-220°C), 170-195°C (e.g., 175-190°C), and 150-169°C (e.g., 160-169°C).

[0055] Another aspect of this application provides aluminum trichloride, which is prepared by the method described in this application, wherein the purity of the aluminum trichloride is ≥98.5% by weight and the total content of metal impurities is ≤0.1% by weight.

[0056] Preferably, the aluminum trichloride has a purity of 98-99.9% by weight (e.g., 98.5-99.8% by weight) and a metal impurity content of 0.001-0.1% by weight (e.g., 0.005-0.015% by weight). Typically, the metal impurities refer to metals other than aluminum that are originally present in the raw material, including but not limited to iron, nickel, vanadium, sodium, or combinations thereof.

[0057] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0058] Example

[0059] A. Source of raw materials:

[0060] Alumina clay pellets (purchased from Zibo Henghuan Aluminum Co., Ltd.)

[0061] Petroleum coke (0.3-0.8 mm, purchased from Jiangsu Taizhi New Material Technology Co., Ltd.)

[0062] Aluminum-coal powder (purchased from Shandong Luoqi Aluminum Co., Ltd.)

[0063] Phosgene synthesis exhaust gas (from Ningxia Ruitai Technology Co., Ltd.)

[0064] Carbon monoxide (99.9% purity, purchased from Yangzhou Baohong Industrial Gases Co., Ltd.)

[0065] Chlorine gas (from Ningxia Ruitai Technology Co., Ltd.)

[0066] B. Equipment:

[0067] High-temperature reactor (model TFH-1200-100-Ⅱ-440, purchased from Anhui Kemi Instrument Co., Ltd.)

[0068] C. Testing or analysis methods

[0069] The raw materials were analyzed using the following methods: Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) (Agilent 5110) and Elemental Analyzer (Thermo Fisher Scientific FlashSmart™).

[0070] Aluminum trichloride yield = m 收料 *w 收料中铝含量 / (m 铝源 *w 铝源中铝含量 )

[0071] m 收料 Refers to the quality of received materials;

[0072] w 收料中铝含量 This refers to the Al content in the received material as determined by ICP.

[0073] m 铝源 This refers to the initial quality of the aluminum source.

[0074] w 铝源中铝含量 This refers to the Al content in the initial feed as measured by ICP.

[0075] Aluminum trichloride purity: The aluminum trichloride content was determined by potentiometric titration (GB / T3959-2023).

[0076] Example 1

[0077] 500g of alumina-containing clay pellets (75% alumina, 12% carbon) with a particle size of 0.1-0.15mm (100-150 mesh) and 30g of petroleum coke (99% carbon) were dried at 100℃ to remove moisture, yielding 420g of aluminum powder (89% alumina, 10% carbon) and 28g of carbon powder. The aluminum and carbon powders were mixed evenly and placed in a high-temperature reactor. The mixture was calcined at 350℃ under a nitrogen atmosphere for 1 hour, then the temperature was raised to 600℃, and chlorine gas was introduced at a rate of 40L / h for 6 hours. The resulting gaseous product underwent three-stage condensation, with the first-stage condensation temperature controlled at 215℃, the second-stage at 183℃, and the third-stage at 167℃, yielding 950g of aluminum trichloride (97% yield, 99.8% purity, and 50ppm metallic impurities).

[0078] Example 2

[0079] 500g of alumina-containing clay pellets (75% alumina, 12% carbon) with a sieve particle size of 0.1-0.15mm (100-150 mesh) were dried at 105℃ to remove moisture, yielding 420g of aluminum powder (89% alumina, 10% carbon). The aluminum powder was placed in a high-temperature reactor and calcined at 300℃ under a nitrogen atmosphere for 1.5h. The temperature was then raised to 750℃, and 40L / h of chlorine and 16L / h of phosgene were introduced to synthesize the tail gas (92% carbon monoxide). The reaction was carried out for 6h. The resulting gaseous product underwent three-stage condensation, with the first-stage condensation temperature controlled at 203℃, the second-stage at 190℃, and the third-stage at 165℃. No carbon monoxide was detected in the tail gas collection device. 923g of aluminum trichloride was obtained, with a yield of 93%, a purity of 98.5%, and a metallic impurity content of 120ppm.

[0080] Example 3

[0081] 500g of aluminum-coal powder (52% alumina, 5% carbon) with a sieve particle size of 0.1-0.15mm (100-150 mesh) was dried at 103℃ to remove moisture, yielding 470g of aluminum powder (55% alumina, 3% carbon). The aluminum powder was placed in a high-temperature reactor and calcined at 400℃ under an argon atmosphere for 2 hours. The temperature was then increased to 750℃, and 28L / h of chlorine and 19L / h of carbon monoxide were introduced, with a reaction time of 6 hours. The resulting gaseous product underwent three-stage condensation, with the first-stage condensation temperature controlled at 208℃, the second-stage at 176℃, and the third-stage at 166℃. No carbon monoxide was detected in the tail gas collection device. 653g of aluminum trichloride was obtained, with a yield of 95%, a purity of 98.7%, and a metallic impurity content of 100ppm.

[0082] Examples 4-7

[0083] Using the same reaction apparatus as in Example 1, and following the steps and conditions of Example 1, with only the quality of petroleum coke changed, the aluminum trichloride preparation results are shown in Table 1:

[0084] Table 1. Preparation effects of Examples 4-7

[0085]

[0086] As can be seen from the data in Table 1, increasing the amount of carbon slightly improves the yield and purity of aluminum trichloride.

[0087] Examples 8-10

[0088] Using the same reaction apparatus as in Example 1, and following the steps and conditions of Example 1, with only the particle size of the alumina white spheres being changed, the preparation results of aluminum trichloride are shown in Table 2:

[0089] Table 2 Preparation effects of Examples 8-11

[0090]

[0091] Examples 11-14

[0092] Using the same reaction apparatus as in Example 1, and following the steps and conditions of Example 1, only the calcination and chlorination temperatures were changed, the preparation results of aluminum trichloride are shown in Table 3:

[0093] Table 3. Preparation effects of Examples 12-15

[0094]

[0095] Examples 15-18

[0096] Using the same reaction apparatus as in Example 1, and following the steps and conditions of Example 1, with only the carbon source changed, the preparation results of aluminum trichloride are shown in Table 5:

[0097] Table 5. Preparation effects of Examples 20-23

[0098]

[0099] Comparative Example 1:

[0100] 500g of alumina-containing clay pellets (75% alumina, 12% carbon) with a sieve particle size of 0.1-0.15mm (100-150 mesh) and 30g of petroleum coke (99% carbon) were mixed evenly and placed in a high-temperature reactor. The mixture was calcined at 350℃ under a nitrogen atmosphere for 1 hour, then the temperature was raised to 600℃ and chlorine gas was introduced at a rate of 40L / h. The reaction was continued for 6 hours. The resulting gaseous product underwent three-stage condensation, with the first-stage condensation temperature controlled at 215℃, the second-stage at 183℃, and the third-stage at 167℃, yielding 878.5g of aluminum trichloride, with a yield of 85.7%, a purity of 95.4%, and a metallic impurity content of 160ppm.

[0101] Comparative Example 2:

[0102] 500g of alumina-containing clay pellets (75% alumina, 12% carbon) with a particle size of 0.1-0.15mm (100-150 mesh) and 30g of petroleum coke (99% carbon) were dried at 100℃ to remove moisture, yielding 420g of aluminum powder (89% alumina, 10% carbon) and 28g of carbon powder. The aluminum and carbon powders were mixed evenly and placed in a high-temperature reactor. The temperature was raised to 600℃, and chlorine gas was introduced at a rate of 40L / h for 6 hours. The resulting gaseous product underwent three-stage condensation, with the first-stage condensation temperature controlled at 215℃, the second-stage at 183℃, and the third-stage at 167℃, yielding 972g of aluminum trichloride (90% yield, 96.7% purity, and 186ppm metallic impurities).

[0103] Comparative Example 3:

[0104] 500g of commercially available alumina (99% alumina content, sieved particle size 0.1-0.15mm (100-150 mesh)) and 93g of petroleum coke (99% carbon content) were dried at 100℃ to remove moisture, yielding 495g of alumina powder (99.9% alumina content) and 195g of carbon powder. The aluminum and carbon powders were mixed evenly and placed in a high-temperature reactor. The temperature was raised to 600℃, and chlorine gas was introduced at a rate of 40L / h for 6 hours. The resulting gaseous product underwent three-stage condensation, with the first-stage condensation temperature controlled at 215℃, the second-stage at 183℃, and the third-stage at 167℃, yielding 1280g of aluminum trichloride (99% yield, 99.85% purity, and 45ppm metallic impurities).

[0105] Comparative Example 4:

[0106] 500g of alumina (99% alumina content, sieved particle size 0.1-0.15mm (100-150 mesh)) and 30g of petroleum coke (99% carbon content) were dried at 100℃ to remove moisture, yielding 495g of alumina powder (99.9% alumina content) and 28g of carbon powder. The aluminum and carbon powders were mixed evenly and placed in a high-temperature reactor. The mixture was calcined at 350℃ under a nitrogen atmosphere for 1 hour, then the temperature was raised to 600℃, and chlorine gas was introduced at a rate of 40L / h for 6 hours. The resulting gaseous product underwent three-stage condensation, with the first-stage condensation temperature controlled at 215℃, the second-stage at 183℃, and the third-stage at 167℃, yielding 410g of aluminum trichloride, with a yield of 31.7%, a purity of 99.81%, and a metallic impurity content of 47ppm.

Claims

1. A method for preparing aluminum trichloride, comprising the following steps: (1) Provide dry aluminum and carbon sources; (2) The dried aluminum source obtained in step (1) is calcined under an inert atmosphere; (3) The calcined aluminum source obtained in step (2), the dried carbon source obtained in step (1), and chlorine gas are mixed and chlorinated to obtain aluminum trichloride. The aluminum source also includes carbon. In the dried aluminum source and dried carbon source, the weight ratio of aluminum to carbon, calculated as alumina and carbon, is ≤1:0.

3.

2. The method as described in claim 1, wherein, The aluminum source refers to an aluminum-containing material with an alumina content of ≥50% by weight (e.g., ≥60% by weight, ≥70% by weight, 50-90% by weight, 50-80% by weight); or The aluminum source includes one or more of the following: alumina adsorbent, kaolin, alumina powder, bauxite, fly ash, and alumina slag; or Based on the total weight of the aluminum source, the carbon content is ≥1% by weight, for example ≥3% by weight, ≥5% by weight, 1-30% by weight, 2-25% by weight, 3-20% by weight, 4-15% by weight; or The aluminum source may also contain other substances, such as hydrogen, silicon dioxide, iron, nickel, vanadium, sodium, phosphorus, etc.; or Other substances account for 0-50% by weight of the total weight of the aluminum source, for example, 0-40% by weight, 0.1-40% by weight, and 1-40% by weight.

3. The method as described in claim 1, wherein, The carbon source is a solid carbon source or a gaseous carbon source; or The solid carbon source is one or more of petroleum coke, activated carbon, coke, charcoal, and calcined coke; or The gaseous carbon source is one or more of carbon monoxide or phosgene synthesis tail gas.

4. The method of claim 1, wherein, In the dried aluminum source and dried carbon source, the weight ratio of aluminum to carbon, calculated as alumina and carbon, is ≤1: 0.3, for example 1: (0.01-0.3), 1: (0.05-0.3), 1: (0.1-0.3), 1: (0.15-0.3), 1: (0.15-0.29), 1: (0.1-0.2).

5. The method of claim 1, wherein, Methods for providing dry aluminum and carbon sources include heating the aluminum and carbon sources (in the case of solid carbon sources); or The heating temperature is usually 50-300℃; or When using a gaseous carbon source, drying can be achieved through condensation dehydration or dehydration with a desiccant; or The moisture content of the dried aluminum and carbon sources is ≤1 wt%, typically ≤0.5 wt%, for example ≤0.1 wt% (e.g. 0.001-1 wt%, 0.05-1 wt%).

6. The method of claim 1, wherein, In step (2) above, the roasting temperature is 200-800℃, for example 250-700℃, 300-600℃, or 300-500℃; or In step (2) above, the inert atmosphere is nitrogen, a rare gas, or a combination thereof; or In step (2) above, the roasting time is 0.5-10h, for example 0.5-5h or 0.5-3h.

7. The method of claim 1, wherein, The chlorination temperature is 300-1200℃, or 400-950℃, or 500-900℃; the chlorination time is 1-20h, for example 2-15h, 3-10h, etc.

8. The method of claim 1, wherein, Multi-stage condensation can be used to collect aluminum trichloride products, for example, aluminum trichloride products can be collected through 2-6 stages of condensation; or The multi-stage condensation is 2-4 stages, for example, three stages; or The three condensation temperatures of the three-stage condenser, from high to low, are 200-230℃ (e.g., 200-220℃), 170-195℃ (e.g., 175-190℃), and 150-169℃ (e.g., 160-169℃).

9. An aluminum trichloride, prepared by the method described in this application, wherein the aluminum trichloride has a purity ≥ 98.5% by weight and a total metal impurity content ≤ 0.1% by weight.

10. The aluminum trichloride as described in claim 9, wherein, The aluminum trichloride has a purity of 98-99.9% by weight (e.g., 98.5-99.8% by weight) and a metal impurity content of 0.001-0.1% by weight (e.g., 0.005-0.015% by weight).

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