A method for preparing molybdenum dichloride dioxide by metathesis reaction using industrial grade hydrogen chloride gas

Abstract

The application discloses a method for preparing molybdenum dichloride dioxide by means of metathesis reaction using industrial-grade hydrogen chloride gas. The method is as follows: a molybdenum source is loaded into a reaction zone of a quartz tube type reaction furnace, and an inert atmosphere is kept in the reaction furnace; the reaction furnace is heated, and then industrial-grade hydrogen chloride gas is introduced, and constant temperature reaction is carried out; after the reaction is completed, yellowish white crystalline molybdenum dichloride dioxide crude product is obtained; the obtained crude product is placed in a sublimation device, and under the protection of an inert atmosphere, the sublimation zone is heated and sublimated at constant temperature, and the yellowish crystalline product molybdenum dichloride dioxide is obtained by cooling at the receiving end. The application uses industrial-grade hydrogen chloride gas (containing trace water) as a chlorine source and a reaction medium, and prepares molybdenum dichloride dioxide by means of metathesis reaction with a molybdenum source under high-temperature and water-free conditions.

Description

Technical Field

[0001] This invention relates to the field of compound preparation technology, and specifically to a method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction. Background Technology

[0002] Molybdenum dioxide (MoO2Cl2), with the chemical formula MoO2Cl2 and a molecular weight of 198.85 g / mol, is a yellow-orange solid powder that sublimates upon heating to 159℃ and decomposes at 184℃. Its molybdenum center is coordinated with two oxygen atoms and two chlorine atoms, forming a tetrahedral structure.

[0003] In recent years, molybdenum dichlorodioxide (MoD) has attracted considerable attention as a precursor for depositing metallic molybdenum films using vacuum deposition techniques (CVD or ALD) in the semiconductor industry. Molybdenum films deposited using MoD generally exhibit better performance than those deposited using organometallic molybdenum precursors because MoD contains no nitrogen or carbon atoms, resulting in a higher purity film. Furthermore, MoD is widely used as a catalyst for the liquid-phase epoxidation of olefins, making it a versatile and cost-effective non-noble metal transition metal complex catalyst in organic synthesis.

[0004] Currently, the main methods for preparing molybdenum dioxide dichloride include the following:

[0005] 1. Direct chlorination with chlorine gas

[0006] The traditional method involves reacting molybdenum dioxide (MoO2) or molybdenum trioxide (MoO3) with chlorine gas:

[0007] MoO2 + Cl2 → MoO2Cl2;

[0008] 2MoO3+ 2Cl2→ 2MoO2Cl2+ O2;

[0009] The above method involves passing excess chlorine gas through the reactants at a high temperature of 200–400℃ to carry out a chlorination reaction.

[0010] 2. Thionyl chloride process (CN120712237A)

[0011] Yuan Yi Semiconductor Materials Co., Ltd. disclosed a method for preparing molybdenum dichlorodioxide without using chlorine gas, which involves reacting molybdenum trioxide with thionyl chloride (… The reaction occurs in a non-coordinated solvent: MoO3 + SOCl2 → MoO2Cl2 + SO2.

[0012] 3. Reaction method of molybdenum trioxide with concentrated hydrochloric acid

[0013] Literature reports that the simplest method for preparing molybdenum dioxide dichlorotrioxide is to treat molybdenum trioxide with concentrated hydrochloric acid.

[0014] MoO3+ 2HCl → MoO2Cl2+ H2O;

[0015] This method, described in patent CN121405130A, is used for the production of electronic-grade molybdenum dichlorodioxide: molybdenum trioxide is reacted with 4–5 times its mass of concentrated hydrochloric acid at 80–100°C.

[0016] 4. Ammonium molybdate / ammonium chloride heating method

[0017] Literature reports that molybdenum dioxide dichlorodioxide can be obtained by mixing ammonium molybdate and ammonium chloride in a certain molar ratio, adding an appropriate amount of aqueous solution, stirring to dissolve, and then heating to react.

[0018] The aforementioned existing technologies generally suffer from the following problems:

[0019] (1) The chlorine method faces serious regulatory barriers. Chlorine is a highly toxic chemical, and its purchase requires an application for a purchase license from the provincial public security authority; the chlorination process has been listed as a high-risk chemical process, and new chlorination-related projects need to be reviewed by multiple departments, making the approval process extremely strict.

[0020] (2) The concentrated hydrochloric acid method has inherent defects. Molybdenum dioxide dichloride decomposes upon contact with water: MoO2Cl2 + H2O → MoO3 + 2HCl. Even trace amounts of moisture in the air can cause its decomposition. The existing concentrated hydrochloric acid method reacts in the presence of a large amount of water, and the reaction equilibrium is severely restricted by the presence of water, resulting in a low yield; moreover, the product is easily hydrolyzed in aqueous systems, requiring complex separation and purification processes.

[0021] (3) The thionyl chloride process uses highly toxic reagents. SOCl2 itself is toxic and corrosive, and its synthesis process still involves chlorine gas, which does not fundamentally eliminate the dependence on chlorine resources. In addition, the by-product SO2 requires additional tail gas treatment.

[0022] (4) The ammonium molybdate / ammonium chloride aqueous solution method also faces the problem of aqueous phase reaction. The presence of a large amount of water leads to product hydrolysis, resulting in low yield, and the product needs to undergo multiple post-processing steps such as filtration, washing, and drying.

[0023] (5) In summary, existing technologies have failed to resolve the core issue of moisture interference in the preparation of molybdenum dichlorodioxide. The concentrated hydrochloric acid method and the ammonium molybdate method introduce large amounts of water, which limits the reaction to equilibrium and makes the product prone to hydrolysis. Although the chlorine method and the thionyl chloride method can achieve anhydrous conditions, they face challenges such as the regulation of highly toxic chemicals, approval of hazardous processes, and the use of highly toxic reagents. Therefore, developing a method that completely avoids chlorine and efficiently prepares molybdenum dichlorodioxide under anhydrous or low-water conditions has significant industrial application value and is of urgent practical importance. Summary of the Invention

[0024] To address the above technical problems, this invention provides a method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination relocation reaction. This invention uses industrial-grade hydrogen chloride gas (containing trace amounts of water) as the chlorine source and reaction medium, and prepares molybdenum dioxide dichlorodioxide under high-temperature and anhydrous conditions via a coordination relocation reaction with a molybdenum source.

[0025] The purpose of this invention is to provide a method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction, comprising the following steps:

[0026] The molybdenum source is loaded into the reaction zone of the tubular reactor, and the reaction zone is kept in an inert atmosphere.

[0027] The reaction zone was heated, and then industrial-grade hydrogen chloride gas was introduced and the reaction was carried out at a constant temperature. After the reaction was completed, a pale yellow-white crystalline crude molybdenum dioxide dichloride product was obtained.

[0028] The crude product was placed in a sublimation apparatus and heated to a constant temperature in the sublimation zone under an inert atmosphere. The receiving end was then cooled to obtain a pale yellow crystalline product, molybdenum dioxide dichloride.

[0029] In some embodiments of the present invention, the inert gas in the inert atmosphere is nitrogen and / or argon; the flow rate of the inert gas is 20~50 mL / min.

[0030] In some embodiments of the present invention, the molybdenum source is selected from molybdenum trioxide and / or molybdic acid.

[0031] In some embodiments of the present invention, the reaction zone is heated to a temperature of 200-300°C.

[0032] In some embodiments of the present invention, the water content of the industrial-grade hydrogen chloride gas is 150~300 ppm; the concentration of the industrial-grade hydrogen chloride gas is >99.5%, preferably 99.9%.

[0033] In some embodiments of the present invention, the flow rate of the industrial-grade hydrogen chloride gas is 150~200 mL / min.

[0034] In some embodiments of the present invention, the isothermal reaction temperature is 200~300°C and the reaction time is 3~4 hours.

[0035] In some embodiments of the present invention, the inert gas in the sublimation apparatus includes nitrogen and / or argon.

[0036] In some embodiments of the present invention, the heating temperature for constant temperature sublimation is 180~190°C, and the constant temperature sublimation time is 4~6 hours; the receiving end is cooled to 20~70°C.

[0037] The core technological innovation of this invention lies in the ingenious utilization of trace amounts of water: In existing technologies, molybdenum dioxide dichlorodeliquinates upon contact with water, and the large amount of water in concentrated hydrochloric acid is the fundamental reason for product decomposition and decreased yield. However, this invention discovers that trace amounts of water are not simply a destructive factor in the reaction, but rather possess unique catalytic / ionizing effects. The core reaction mechanism is as follows:

[0038] Ionization of HCl: Industrial-grade hydrogen chloride gas contains trace amounts of moisture. Although this moisture is insufficient to form liquid hydrochloric acid, it can be adsorbed onto the surface of the molybdenum source solid in the reaction system, promoting partial dissociation of hydrogen chloride molecules and producing a small amount of H+. + and Cl - Ions. In the absence of trace amounts of water, dry hydrogen chloride molecules exist in a covalent form, are chemically inert, and have an extremely low reaction rate.

[0039] H + Neutralization effect: The generated H + The proton undergoes a neutralization reaction with the molybdate or hydroxyl group, promoting the cleavage of the Mo-OH bond, resulting in Cl. - Coordination creates conditions.

[0040] Cl - Coordination effect: Cl produced by dissociation - It enters the coordination layer of molybdenum, undergoes a ligand substitution reaction, and forms a Mo-Cl bond.

[0041] High-temperature dehydration and equilibrium-driven reaction: The reaction is carried out at a high temperature of 200-300℃, and the generated water is promptly removed in the form of water vapor, allowing the reaction equilibrium to continuously advance to the right, while avoiding hydrolysis caused by water contacting the product. The reaction is carried out under anhydrous conditions, and the product is generated directly in solid form or sublimated and collected in gaseous form without the need for subsequent complex separation.

[0042] The core reaction equation of this invention is:

[0043] MoO3 + 2HCl (g) → MoO2Cl2 + H2O (g)↑;

[0044] MoO2(OH)2 + 2HCl (g) → MoO2Cl2 + 2H2O (g)↑ (applicable to molybdic acid);

[0045] This invention extends this reaction to industrial-grade hydrogen chloride gas conditions and utilizes the catalytic / ionization effect of trace amounts of water and a high-temperature dehydration mechanism to achieve efficient conversion, which is the original technical concept of this invention.

[0046] The beneficial effects of this invention are:

[0047] 1. Completely avoids the use of chlorine gas, eliminating regulatory barriers. This invention uses industrial-grade hydrogen chloride gas as the chlorine source. Hydrogen chloride is a bulk industrial chemical, and its procurement is not subject to the approval restrictions for highly toxic chemicals. It does not require the stringent safety review of high-risk chlorination chemical processes, significantly reducing the institutional costs of project implementation.

[0048] 2. Ingenious Utilization of Trace Amounts of Water. This invention is the first to discover and utilize the catalytic / ionization effect of trace amounts of water in hydrogen chloride gas, solving the problem of low reaction rate in traditional anhydrous hydrogen chloride. This is a breakthrough from the technical prejudice in the prior art that "molybdenum dioxide dichloride hydrolyzes upon contact with water"—trace amounts of water are not a destructive factor under certain conditions, but rather a catalyst that promotes the reaction.

[0049] 3. Completely solves the hydrolysis problem. Existing concentrated hydrochloric acid and ammonium molybdate aqueous solution methods are carried out in the presence of a large amount of water. The product MoO2Cl2 deliquesces upon contact with water, and the reaction equilibrium is limited by water, resulting in low yields. This invention reacts under high-temperature and anhydrous conditions, and the generated water is continuously removed in the form of water vapor, avoiding contact between the product and water. The reaction equilibrium shifts to the right, and the yield is significantly improved.

[0050] 4. High product purity and simple post-processing. The product of this invention is generated directly in solid form or sublimated and collected in gaseous form, without the need for complex post-processing steps such as filtration, washing, and drying. The product purity can reach over 99%, and after simple sublimation purification, the purity can reach over 99.9%, meeting the purity requirements of semiconductor CVD / ALD precursors.

[0051] 5. The process is continuous and suitable for large-scale production. This invention uses a tubular reactor to continuously introduce hydrogen chloride gas, enabling continuous production. The equipment is simple, easy to operate, and suitable for industrial scale-up.

[0052] 6. Raw materials are widely available and inexpensive. Industrial-grade hydrogen chloride gas is a bulk industrial chemical with a stable supply and low price; molybdenum trioxide, molybdic acid, and ammonium molybdate are all common molybdenum chemical products with controllable costs.

[0053] 7. Environmentally friendly. The byproduct of this invention is water vapor, with no harmful gas emissions; the hydrogen chloride in the reaction tail gas can be absorbed and recycled with water, making it environmentally friendly. Attached Figure Description

[0054] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0055] Figure 1 This is the XRD pattern of molybdenum dichlorodioxide obtained in Example 1 of the present invention. Detailed Implementation

[0056] To address the technical problems identified in the background section, the present invention provides the following solution:

[0057] The purpose of this invention is to provide a method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction, comprising the following steps:

[0058] The molybdenum source is loaded into the reaction zone of a quartz tube reactor, and the reactor is kept in an inert atmosphere.

[0059] The reactor was heated, and then industrial-grade hydrogen chloride gas was introduced and the reaction was carried out at a constant temperature. After the reaction was completed, a pale yellow-white crystalline crude molybdenum dioxide dichloride product was obtained.

[0060] The crude product was placed in a sublimation apparatus and heated to a constant temperature in the sublimation zone under an inert atmosphere. The receiving end was then cooled to obtain a pale yellow crystalline product, molybdenum dioxide dichloride.

[0061] In a specific embodiment of the present invention, the inert gas in the inert atmosphere is nitrogen and / or argon; the flow rate of the inert gas is 20~50 mL / min, and for example, it can be 20, 25, 30, 35, 40, 45, 50 mL / min, or any range between any two values.

[0062] In a specific embodiment of the present invention, the molybdenum source is selected from molybdenum trioxide and / or molybdic acid.

[0063] In a specific embodiment of the present invention, the reaction zone is heated to a temperature of 200-300°C. In this invention, when the reaction temperature is below 200°C, the removal of moisture is incomplete; above 300°C, the product is easily decomposed, and the product yield decreases.

[0064] In a specific embodiment of the present invention, the water content of the industrial-grade hydrogen chloride gas is 150~300 ppm. Exemplarily, it can be 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300 ppm, or any range between any two values. The concentration of the industrial-grade hydrogen chloride gas is >99.5%, preferably 99.9%. This invention utilizes the trace amount of water contained in the industrial-grade hydrogen chloride gas. After being adsorbed by the solid surface of the molybdenum source in the reaction system, it can promote the partial dissociation of hydrogen chloride molecules, generating a small amount of H₂. + and Cl - The ions then undergo a chlorination reaction. In the absence of trace amounts of water, the dry hydrogen chloride molecules exist in a covalent form, are chemically inert, and have an extremely low reaction rate. If the water content is high, hydrochloric acid will hydrolyze the product, molybdenum dioxide dichlorodioxide.

[0065] In a specific embodiment of the present invention, the flow rate of the industrial-grade hydrogen chloride gas is 150~200 mL / min. Exemplarily, it can be 150, 160, 170, 180, 190, 200 mL / min, or any range between any two values. When the industrial-grade hydrogen chloride gas reacts with the Mo source, if the flow rate is too low, it is insufficient to achieve adequate contact with Mo; if the flow rate is too high, it is wasteful and increases costs.

[0066] In a specific embodiment of the present invention, the temperature of the isothermal reaction is 200~300℃, and the reaction time is 3~4 hours.

[0067] In a specific embodiment of the present invention, the inert gas in the sublimation apparatus includes nitrogen and / or argon.

[0068] In a specific embodiment of the present invention, the heating temperature for constant temperature sublimation is 180~190°C, and the constant temperature sublimation time is 4~6 hours; the receiving end is cooled to 20~70°C.

[0069] 1. Catalytic / ionization effect of trace water: This invention is the first to discover and utilize the dual role of trace water in anhydrous hydrogen chloride gas systems—promoting HCl ionization (providing activity) and The method completely solves the fundamental problem of product hydrolysis in aqueous phase methods by removing the water generated in the reaction through high-temperature evaporation.

[0070] 2. High-Temperature Dehydration and Equilibrium-Driven: The reaction proceeds at high temperatures, where the generated water is continuously removed as steam, shifting the reaction equilibrium to the right while preventing contact between water and the product. The product can be generated directly in solid form or sublimated and collected in gaseous form, simplifying post-processing.

[0071] 3. Safe and readily available raw materials: Although industrial-grade hydrogen chloride gas is a precursor chemical, it is also a bulk industrial chemical. Compared with chlorine, its procurement is not subject to the approval restrictions for highly toxic chemicals, and it is safer and more environmentally friendly than thionyl chloride and concentrated hydrochloric acid.

[0072] 4. The reaction mechanism is fundamentally different: Existing technologies either react in a large amount of water, leading to product hydrolysis, or use highly toxic chlorinating reagents; the present invention achieves coordination position replacement through the catalytic / ionization effect of trace amounts of water under anhydrous gas phase conditions, and the reaction mechanism and condition control method are significantly different from existing technologies. The present invention utilizes the dual role of trace amounts of water in hydrogen chloride gas: (1) promotes the ionization of HCl molecules, producing Cl - and H + (2) H + Neutralize OH in molybdenum source - Cl -The water is coordinated into the molybdenum center. Under high-temperature conditions, the water generated in the reaction is promptly removed in the form of water vapor to avoid contact with the product and hydrolysis, while simultaneously shifting the reaction equilibrium to the right, achieving efficient conversion.

[0073] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0074] Example 1

[0075] This embodiment provides a method for preparing molybdenum dichlorodioxide using molybdenum trioxide-hydrogen chloride gas, as detailed below:

[0076] I. Preparation of Crude Product

[0077] 20g of molybdenum trioxide (MoO3, purity ≥99.9%) was placed in a quartz tube reactor and positioned in the reaction zone. The air in the reaction system was replaced with high-purity nitrogen, and after replacement, nitrogen was maintained at a flow rate of 50 mL / min for purging. The reactor was heated to 250℃. Industrial-grade hydrogen chloride gas (water content approximately 200 ppm) was introduced at a flow rate of 200 mL / min, and the reaction was carried out at 250℃ for 4 hours. During the reaction, a pale yellow-white solid deposit gradually appeared at the reactor outlet. After the reaction was completed, the hydrogen chloride supply was stopped, and the mixture was allowed to cool to room temperature under nitrogen protection. The product was collected, yielding approximately 25.8g of pale yellow-white crystalline crude molybdenum dichlorodioxide (yield based on molybdenum approximately 93.4%). XRD analysis identified it as MoO2Cl2 (see [link to XRD pattern]). Figure 1 ICP-MS analysis showed that the total amount of metal impurities was <100 ppm.

[0078] II. Product Sublimation and Purification

[0079] 10 g of the crude molybdenum dioxide dichloride prepared in step one was placed in a sublimation apparatus. Under nitrogen protection, the sublimation zone was heated to 180°C, and the receiving end was cooled to 50°C. Sublimation was maintained at this temperature for 4 hours. Approximately 8.8 g of pale yellow crystalline product was collected at the receiving end, with a recovery rate of 88%. ICP-MS analysis showed that the product purity was ≥99.9%, tungsten content ≤50 ppb, and iron content ≤20 ppb, meeting the requirements for semiconductor-grade CVD precursors.

[0080] Example 2

[0081] This embodiment provides a method for preparing molybdenum dichlorodioxide using molybdenum trioxide-hydrogen chloride gas, as detailed below:

[0082] I. Preparation of Crude Product

[0083] 20g of molybdenum trioxide (MoO3, purity ≥99.9%) was placed in a quartz tube reactor and positioned in the reaction zone. The air in the reaction system was replaced with high-purity nitrogen gas, and after replacement, the nitrogen flow rate was maintained at 50 mL / min for purging. The reactor was heated to 300℃. Industrial-grade hydrogen chloride gas (water content approximately 300 ppm) was then introduced at a flow rate of 150 mL / min, and the reaction was carried out at 300℃ for 3 hours, yielding 24.9g of crude molybdenum dichlorodioxide, with a yield of approximately 90.1%.

[0084] II. Product Sublimation and Purification

[0085] Take 24.9 g of the crude product molybdenum dioxide dichloride prepared in step one and place it in a sublimation apparatus. Under nitrogen protection, heat the sublimation zone to 180°C, cool the receiving end to 50°C, and maintain the temperature for sublimation for 4 hours. Collect the product by sublimation condensation to obtain approximately 23.16 g of molybdenum dioxide dichloride, with a yield of approximately 93%. The product purity is ≥99.5%.

[0086] Example 3

[0087] This embodiment provides a method for preparing molybdenum dioxide dichlorohydrate using molybdic acid-hydrogen chloride gas, as detailed below:

[0088] 1. Take 22.6 g of molybdic acid (H₂MoO₄, containing approximately 0.14 mol of molybdenum) and place it in a quartz tube reactor, then place it in the reaction zone. Replace the air in the reaction system with high-purity nitrogen gas, maintaining a nitrogen flow rate of 50 mL / min after replacement. Heat the reactor to 200°C. Switch to industrial-grade hydrogen chloride gas (containing approximately 150 ppm of water) at a flow rate of 200 mL / min, and react at 200°C for 5 hours. During the reaction, the molybdic acid gradually transforms into a pale yellow-white product. After the reaction is complete, cool under nitrogen protection and collect the product to obtain approximately 24.5 g of molybdenum dichlorodioxide (yield based on molybdenum of approximately 88.3%).

[0089] 2. Take 24.5 g of the crude product molybdenum dioxide dichloride prepared in step one and place it in a sublimation apparatus. Under nitrogen protection, heat the sublimation zone to 190°C, cool the receiving end to 50°C, and maintain the temperature for sublimation for 6 hours. Collect approximately 22.3 g of pale yellow crystalline product at the receiving end. After sublimation and condensation, collect approximately 22.3 g of molybdenum dioxide dichloride, with a yield of approximately 91%. The product purity is ≥99.5%.

[0090] Comparative Example 1

[0091] This comparative example provides a method for preparing molybdenum dioxide dichloride using SOCl2, the specific method of which is derived from CN120712237A.

[0092] Comparative Example 2

[0093] This comparative example provides a concentrated hydrochloric acid method for preparing molybdenum dioxide dichlorodioxide, the specific method of which is derived from CN121405130A.

[0094] Table 1 Comparison of the preparation methods of molybdenum dichloride in the embodiments of the present invention and the comparative examples.

[0095]

[0096] The embodiments described above are merely preferred embodiments for fully illustrating the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.

Claims

1. A method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction, characterized in that, Includes the following steps: The molybdenum source is loaded into the reaction zone of the tubular reactor, and the reaction zone is kept in an inert atmosphere. The reaction zone was heated, and then industrial-grade hydrogen chloride gas was introduced and the reaction was carried out at a constant temperature. After the reaction was completed, a pale yellow-white crystalline crude molybdenum dioxide dichloride product was obtained. The crude product was placed in a sublimation apparatus and heated to a constant temperature in the sublimation zone under an inert atmosphere. The receiving end was then cooled to obtain a pale yellow crystalline product, molybdenum dioxide dichloride.

2. The method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction according to claim 1, characterized in that, The inert gas in the inert atmosphere is nitrogen and / or argon; the flow rate of the inert gas is 20~50 mL / min.

3. The method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction according to claim 1, characterized in that, The molybdenum source is selected from molybdenum trioxide and / or molybdic acid.

4. The method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction according to claim 1, characterized in that, The reactor is heated to a temperature of 200~300℃.

5. The method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction according to claim 1, characterized in that, The industrial-grade hydrogen chloride gas has a water content of 150~300 ppm and a concentration >99.5%.

6. The method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction according to claim 1, characterized in that, The flow rate of the industrial-grade hydrogen chloride gas is 150~200 mL / min.

7. The method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction according to claim 1, characterized in that, The isothermal reaction temperature is 200~300℃, and the reaction time is 3~4 hours.

8. The method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction according to claim 1, characterized in that, The inert atmosphere in the sublimation apparatus contains inert gases including nitrogen and / or argon.

9. The method for preparing molybdenum dioxide dichlorodioxide using industrial-grade hydrogen chloride gas via a coordination substitution reaction according to claim 1, characterized in that, The heating and constant temperature sublimation temperature is 180~190℃, and the constant temperature sublimation time is 4~6 hours; the receiving end is cooled to 20~70℃.

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