Preparation method and application of a manganese trifluoride catalyst

Abstract

This invention relates to a method for preparing manganese trifluoride catalyst and its application, belonging to the field of chemical technology. The method includes the following steps: S1, adding manganese powder to a reactor and preheating the reactor; S2, adding nitrogen trifluoride to the reactor and maintaining the reactor temperature until the reaction is complete; S3, the manganese powder and nitrogen trifluoride react to generate manganese trifluoride and nitrogen gas. After the reaction is complete, excess fluorine gas and the nitrogen gas produced in the reaction are removed for tail gas treatment, and the product manganese trifluoride is collected; S4, the prepared manganese trifluoride is added to an octafluoropropane synthesis reactor for use as a catalyst. This invention utilizes the decomposition of nitrogen trifluoride at a certain temperature to generate free fluoride ions, which react completely with manganese powder to generate manganese trifluoride. The reaction process is stable and can achieve continuous industrial production. The conversion rate of octafluoropropane synthesis can be effectively improved through the catalysis of manganese trifluoride.

Description

Technical Field

[0001] This invention belongs to the field of chemical synthesis technology, specifically relating to a method for preparing and applying a manganese trifluoride catalyst to improve the yield of octafluoropropane synthesis. Background Technology

[0002] Octafluoropropane (C3F8) is currently widely used in the semiconductor industry and medical fields. As a plasma etching gas, it can etch intricate circuit patterns onto silicon wafers during semiconductor manufacturing. It can also be used for surface cleaning in CVD equipment, precisely removing surface impurities and improving chip yield. In the medical field, it is primarily used in ultrasound imaging to enhance ultrasound signal backscattering. With the rapid development of the global semiconductor and medical industries, the demand for octafluoropropane is increasing daily.

[0003] Currently, the main industrial processes for producing octafluoropropane include: extracting octafluoropropane as a byproduct from the synthesis of carbon tetrafluoride or hexafluoropropylene; and directly fluorinating hexafluoropropylene and fluorine to produce octafluoropropane. These processes all suffer from drawbacks such as high impurity content, low product conversion rates, and substandard product quality. Therefore, it is necessary to develop a novel fluorination catalyst for the synthesis of octafluoropropane.

[0004] Industrially, manganese trifluoride is mainly prepared by reacting manganese difluoride with fluorine gas. Additionally, there are methods for preparing manganese trifluoride by directly reacting manganese with chlorine trifluoride. CN115947375A discloses a method for synthesizing manganese trifluoride, specifically using perfluoropolyether oil as a dispersion medium to directly react manganese difluoride with fluorine gas to generate manganese trifluoride. The applicant's use of these methods to prepare manganese trifluoride for the catalytic synthesis of octafluoropropane resulted in low yields and substandard product quality. Summary of the Invention

[0005] The purpose of this invention is to develop a method for preparing a manganese trifluoride catalyst, which is used to solve the process technology problems existing in the synthesis of octafluoropropane, thereby improving the synthesis stability of octafluoropropane, increasing the product conversion rate, and improving the product quality indicators.

[0006] The technical solution of the present invention: A method for preparing a manganese trifluoride catalyst includes the following steps: S1. Add manganese powder to the reactor and preheat the reactor; S2. Add nitrogen trifluoride to the reactor and maintain the reactor temperature until the reaction is complete. Manganese powder and nitrogen trifluoride react to produce manganese trifluoride and nitrogen gas. S3. After the reaction is complete, the excess nitrogen trifluoride and the nitrogen gas produced by the reaction are treated as tail gas, and the product manganese trifluoride is collected.

[0007] Preferably, the purity of nitrogen trifluoride is >99.9% and the purity of manganese powder is >99%.

[0008] Preferably, the preheating temperature of the reactor in step S1 is 100~200℃.

[0009] Preferably, the reactor temperature is maintained at 100~200℃ during the reaction process in step S2.

[0010] Preferably, the reaction time in step S2 is 6-8 hours, and the reactor pressure is controlled within 0.1-0.2 MPa.

[0011] Preferably, the molar ratio of manganese powder to nitrogen trifluoride in step S2 is 1:1 to 1.2.

[0012] Preferably, the purity of the product manganese trifluoride in step S3 is >99%.

[0013] Preferably, the method includes the following steps: adding manganese powder with a purity >99% into a reactor, preheating the reactor to 100~200℃, and then introducing nitrogen trifluoride with a purity >99.9% into the reactor at a pressure reduced to 0.1~0.2MPa using a pressure reducer, with a molar ratio of manganese powder to nitrogen trifluoride of 1:1~1.2. The reaction is carried out at 100~200℃ for 6~8 hours, after which heating is stopped. After the reaction is completed, manganese powder and nitrogen trifluoride generate manganese trifluoride and nitrogen gas. The valve of the tail gas absorption tower is opened to exhaust the generated tail gas. Finally, the generated manganese trifluoride product is collected to obtain manganese trifluoride.

[0014] An application of a manganese trifluoride catalyst, used as a catalyst in the synthesis of octafluoropropane.

[0015] Furthermore, manganese trifluoride can provide F· radicals to participate in the synthesis of octafluoropropane, thereby catalyzing the synthesis of octafluoropropane. The raw materials in the synthesis of octafluoropropane are hexafluoropropylene and fluorine gas, with a molar ratio of 1:1.2. The molar ratio of manganese trifluoride catalyst to hexafluoropropylene is 2:1. The catalytic reaction temperature is 30~50 °C, the reaction time is 0.5~1 h, the flow rate of hexafluoropropylene is 10 kg / h, and the flow rate of fluorine gas is 3 kg / h.

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects: This invention provides a method for preparing manganese trifluoride catalyst, which yields manganese trifluoride with higher purity, reaching over 99%. Using this product to catalyze the synthesis of octafluoropropane makes the synthesis reaction more stable and significantly improves the conversion rate of industrial octafluoropropane synthesis. Detailed Implementation

[0017] To further illustrate the inventive objectives and technical solutions of this invention, which can achieve the effects and advantages described above, the present invention will be described in detail below with reference to preferred embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0018] This invention provides a method for preparing manganese trifluoride catalyst, comprising the following steps: adding manganese powder with a purity >99% to a reactor; preheating the reactor to 100-200°C; introducing nitrogen trifluoride with a purity >99.9% into the reactor at a pressure reduced to 0.1-0.2 MPa using a pressure reducer, with a molar ratio of manganese powder to nitrogen trifluoride of 1:1-1.2; reacting at 100-200°C for 6-8 hours, followed by stopping heating. After the reaction is complete, manganese powder and nitrogen trifluoride react to generate manganese trifluoride and nitrogen gas. The tail gas is then discharged by opening the valve of the tail gas absorption tower. Finally, the generated manganese trifluoride product is collected, yielding manganese trifluoride with a purity >99%. Using the prepared manganese trifluoride in the synthesis of octafluoropropane can increase the conversion rate of octafluoropropane to 95%.

[0019] Example 1 A method for preparing a manganese trifluoride catalyst specifically includes the following steps: S1. Add manganese powder with a purity >99% to the reactor and preheat the reactor to 100 ℃.

[0020] S2. After reducing the pressure of nitrogen trifluoride to 0.1 MPa using a pressure reducer, introduce it into the reactor at a molar ratio of manganese powder to nitrogen trifluoride of 1, and maintain the reactor temperature at 100 ℃.

[0021] S3. After reacting in the reactor for 6 hours, manganese powder and nitrogen trifluoride generate manganese trifluoride and nitrogen gas. Open the valve of the tail gas absorption tower and discharge the generated tail gas into the tail gas adsorption tower. Finally, collect the generated manganese trifluoride from the reactor.

[0022] S4. The generated manganese trifluoride was analyzed and tested, and the purity of manganese trifluoride was found to be 95%.

[0023] Application Example 0 Using hexafluoropropylene and fluorine gas as raw materials in a molar ratio of 1:1.2, without the catalyst manganese trifluoride, the synthesis reaction was carried out at a temperature of 40 °C for 1 h. The flow rate of hexafluoropropylene was 10 kg / h, and the flow rate of fluorine gas was 3 kg / h. The resulting octafluoropropane had a conversion rate of 60%.

[0024] Application Example 1 Using hexafluoropropylene and fluorine gas as raw materials in a molar ratio of 1:1.2, Example 1 prepared manganese trifluoride with a purity of 95% as a catalyst. The molar ratio of manganese trifluoride to hexafluoropropylene was 2:1. The catalytic reaction was carried out at a temperature of 40°C for 1 h, with a flow rate of 10 kg / h for hexafluoropropylene and a flow rate of 3 kg / h for fluorine gas. The conversion rate of the synthesized octafluoropropane was 90%.

[0025] Example 2 A method for preparing a manganese trifluoride catalyst specifically includes the following steps: S1. Add manganese powder with a purity >99% to the reactor and preheat the reactor to 200 ℃.

[0026] S2. After reducing the pressure of nitrogen trifluoride to 0.2 MPa using a pressure reducer, introduce it into the reactor at a molar ratio of manganese powder to nitrogen trifluoride of 1.2, and maintain the reactor temperature at 200 ℃.

[0027] S3. After reacting in the reactor for 8 hours, manganese powder and nitrogen trifluoride generate manganese trifluoride and nitrogen gas. Open the valve of the tail gas absorption tower and discharge the generated tail gas into the tail gas adsorption tower. Finally, collect the generated manganese trifluoride from the reactor.

[0028] S4. The generated manganese trifluoride was analyzed and tested, and the purity of manganese trifluoride was found to be 98%.

[0029] Application Example 2 Using hexafluoropropylene and fluorine gas as raw materials in a molar ratio of 1:1.2, Example 2 prepared manganese trifluoride with a purity of 98% as a catalyst. The molar ratio of manganese trifluoride to hexafluoropropylene was 2:1. The catalytic reaction was carried out at a temperature of 40°C for 1 h, with a flow rate of 10 kg / h for hexafluoropropylene and 3 kg / h for fluorine gas. The conversion rate of the synthesized octafluoropropane was 93%.

[0030] Example 3 A method for preparing a manganese trifluoride catalyst specifically includes the following steps: S1. Add manganese powder with a purity >99% to the reactor and preheat the reactor to 150 ℃.

[0031] S2. After reducing the pressure of nitrogen trifluoride to 0.15 MPa using a pressure reducer, introduce it into the reactor at a molar ratio of manganese powder to nitrogen trifluoride of 1.1, and maintain the reactor temperature at 150 ℃.

[0032] S3. After reacting in the reactor for 8 hours, manganese powder and nitrogen trifluoride generate manganese trifluoride and nitrogen gas. Open the valve of the tail gas absorption tower and discharge the generated tail gas into the tail gas adsorption tower. Finally, collect the generated manganese trifluoride from the reactor.

[0033] S4. The generated manganese trifluoride was analyzed and tested, and the purity of manganese trifluoride was found to be 99%.

[0034] Application Example 3 Using hexafluoropropylene and fluorine gas as raw materials in a molar ratio of 1:1.2, Example 3 prepared manganese trifluoride with a purity of 99% as a catalyst. The molar ratio of manganese trifluoride to hexafluoropropylene was 2:1. The catalytic reaction was carried out at a temperature of 40°C for 1 h, with a flow rate of 10 kg / h for hexafluoropropylene and 3 kg / h for fluorine gas. The conversion rate of the synthesized octafluoropropane was 95%.

[0035] Application Example 4 Using hexafluoropropylene and fluorine gas as raw materials in a molar ratio of 1:1.2, Example 3 prepared manganese trifluoride with a purity of 99% as a catalyst. The molar ratio of manganese trifluoride to hexafluoropropylene was 2:1. The catalytic reaction was carried out at a temperature of 40°C for 0.5 h, with a flow rate of 10 kg / h for hexafluoropropylene and a flow rate of 3 kg / h for fluorine gas. The conversion rate of the synthesized octafluoropropane was 92%.

[0036] Application Example 5 Using hexafluoropropylene and fluorine gas as raw materials in a molar ratio of 1:1.2, Example 3 prepared manganese trifluoride with a purity of 99% as a catalyst. The molar ratio of manganese trifluoride to hexafluoropropylene was 2:1. The catalytic reaction was carried out at a temperature of 30°C for 50 minutes, with a flow rate of hexafluoropropylene of 10 kg / h and a flow rate of fluorine gas of 3 kg / h. The conversion rate of the synthesized octafluoropropane was 93%.

[0037] Application Example 6 Using hexafluoropropylene and fluorine gas as raw materials in a molar ratio of 1:1.2, Example 3 prepared manganese trifluoride with a purity of 99% as a catalyst. The molar ratio of manganese trifluoride to hexafluoropropylene was 2:1. The catalytic reaction was carried out at a temperature of 50°C for 40 minutes, with a flow rate of hexafluoropropylene of 10 kg / h and a flow rate of fluorine gas of 3 kg / h. The conversion rate of the synthesized octafluoropropane was 92%.

[0038] Comparative Example 1 The difference between this comparative example and application example 3 is that the manganese trifluoride used is commercially available manganese trifluoride with a purity of 99%, the same purity as in Example 1. The conversion rate of the synthesized octafluoropropane is 85%.

[0039] Comparative Example 2 The difference between this comparative example and application example 3 is that the manganese trifluoride used is commercially available manganese trifluoride with a purity of 90%. The conversion rate of the synthesized octafluoropropane is 80.8%.

[0040] Comparative Example 3 The difference between this comparative example and Example 3 is that the purity of the raw material manganese powder is 90.5%, and the purity of the manganese trifluoride obtained in step S4 is 89%. The process for synthesizing octafluoropropane is the same as in Application Example 3, and the conversion rate of the obtained octafluoropropane is 87.3%.

[0041] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any other changes or modifications made based on the technical concept of the present invention, as well as modifications and equivalent variations made to the above embodiments based on the technical essence of the present invention, should be included within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a manganese trifluoride catalyst, characterized in that, Includes the following steps: S1. Add manganese powder to the reactor and preheat the reactor; S2. Add nitrogen trifluoride to the reactor and maintain the reactor temperature until the reaction is complete. Manganese powder and nitrogen trifluoride react to produce manganese trifluoride and nitrogen gas. S3. After the reaction is complete, the excess nitrogen trifluoride and the nitrogen gas produced by the reaction are treated as tail gas, and the product manganese trifluoride is collected.

2. The method for preparing a manganese trifluoride catalyst according to claim 1, characterized in that, Nitrogen trifluoride has a purity of >99.9%, and manganese powder has a purity of >99%.

3. The method for preparing a manganese trifluoride catalyst according to claim 1, characterized in that, In step S1, the reactor is preheated at a temperature of 100~200℃.

4. The method for preparing a manganese trifluoride catalyst according to claim 1, characterized in that, In step S2, the reactor temperature is maintained at 100~200℃ during the reaction process.

5. The method for preparing a manganese trifluoride catalyst according to claim 1, characterized in that, In step S2, the reaction time is 6-8 hours, and the reactor pressure is controlled within 0.1-0.2 MPa.

6. The method for preparing a manganese trifluoride catalyst according to claim 1, characterized in that, In step S2, the molar ratio of manganese powder to nitrogen trifluoride is 1:1 to 1.

2.

7. The method for preparing a manganese trifluoride catalyst according to claim 1, characterized in that, The purity of the product manganese trifluoride in step S3 is >99%.

8. The method for preparing a manganese trifluoride catalyst according to claim 1, characterized in that, Includes the following steps: Manganese powder with a purity >99% is added to the reactor, which is preheated to 100-200℃. Nitrogen trifluoride with a purity >99.9% is depressurized to 0.1-0.2 MPa through a pressure reducer and then introduced into the reactor at a molar ratio of manganese powder to nitrogen trifluoride of 1:1-1.

2. The reaction is carried out at 100-200℃ for 6-8 hours, after which heating is stopped. After the reaction is completed, manganese powder and nitrogen trifluoride generate manganese trifluoride and nitrogen gas. The tail gas absorption tower valve is opened to exhaust the generated tail gas. Finally, the generated manganese trifluoride product is collected to obtain manganese trifluoride.

9. An application of a manganese trifluoride catalyst, prepared by the method for preparing a manganese trifluoride catalyst according to any one of claims 1-8, characterized in that, It is used as a catalyst in the synthesis of octafluoropropane.

10. The application of the manganese trifluoride catalyst according to claim 9, characterized in that, The raw materials for the synthesis of octafluoropropane are hexafluoropropylene and fluorine gas in a molar ratio of 1:1.

2. The molar ratio of manganese trifluoride catalyst to hexafluoropropylene is 2:

1. The temperature of the catalytic reaction is 30~50 ℃, the reaction time is 0.5~1 h, the flow rate of hexafluoropropylene is 10 kg / h, and the flow rate of fluorine gas is 3 kg / h.