Preparation method of carbonyl fluoride

Abstract

The invention discloses a preparation method of carbonyl fluoride, which comprises the following steps: with hexafluoropropylene and oxygen as raw materials, introducing gas into a reactor filled with a catalyst for reaction at high temperature; the catalyst is one of palladium oxide, ruthenium oxide, platinum oxide and molybdenum oxide. According to the scheme, the cost is low, the raw material utilization rate is high, and compared with other carbonyl fluoride synthesis methods, the reaction does not involve phosgene, fluorine and other dangerous chemicals, and reaction by-products are few. In addition, according to the method, the toxicity of raw materials is small, hexafluoropropylene can be completely reacted under the condition of excessive oxygen, the reaction process is environment-friendly and simple, and basically no three wastes are generated. According to the method, hexafluoropropylene and oxygen are adopted as raw materials which are common chemical raw materials and are cheap and easy to obtain, and the method is simple in reaction process, mild in reaction, easy to operate and suitable for industrial production.

Description

Technical Field

[0001] The invention belongs to the field of fine chemicals and relates to a method for preparing carbonyl fluoride. Background Art

[0002] Carbonyl fluoride is an important fine chemical intermediate and an important upstream raw material for drugs such as the antihypertensive drug candesartan cilexetil and the anticancer drug domperidone maleate, as shown in chemical reaction pathway 1 and chemical reaction pathway 2. In addition, high-purity carbonyl fluoride can also be used as an etching gas for electronic chips and can be widely used in the semiconductor industry.

[0003] Chemical reaction pathway 1:

[0004]

[0005] Chemical reaction pathway 2:

[0006]

[0007] At present, there are many patents for the preparation method of carbonyl fluoride. The Chinese patent CN101080362A carbonyl fluoride manufacturing method reports the reaction of preparing carbonyl fluoride with fluorine gas and carbon monoxide as raw materials, the reaction of preparing carbonyl fluoride (chemical reaction path 3), and the other is to use phosgene as raw material, react with hydrogen fluoride, and prepare the reaction of carbonyl fluoride (chemical reaction path 4). The first method raw material fluorine gas and carbon monoxide are both highly toxic gases, which are harmful to the human body. Fluorine gas is a strong oxidizing gas and corrosive. In addition, carbon monoxide is a flammable and explosive gas with a wide explosion range. Therefore, the process is dangerous and needs to invest in high safety costs in research and development production. The second method phosgene and hydrogen fluoride are also highly toxic or corrosive gases, and the cost is also high during the research and development experiment.

[0008] Chemical reaction pathway 3:

[0009] CO+F2=COF2

[0010] Chemical reaction pathway 4:

[0011] COCl2+HF=COF2+HCl. Summary of the invention

[0012] In order to solve the above technical problems, the present invention provides a preparation method for synthesizing carbonyl fluoride, which can avoid the problem of high toxicity of raw materials and the safety problem of the process.

[0013] The technical solution of the present invention is:

[0014] A method for preparing carbonyl fluoride, using hexafluoropropylene and oxygen as raw materials, aerating a reactor filled with a catalyst under high temperature conditions for reaction, aerating again when stable carbonyl fluoride is generated, and then collecting;

[0015] The catalyst is one of palladium oxide, ruthenium oxide, platinum oxide and molybdenum oxide.

[0016] Preferably, the specific steps are as follows:

[0017] S1, filling the catalyst into the sieve plate with holes inside the tubular reactor and sealing it with a flange head;

[0018] S2, purging nitrogen into the reactor under high temperature conditions to remove moisture in the reactor and activate the catalyst;

[0019] S3, hexafluoropropylene and oxygen are introduced into the reactor at a certain flow ratio, and react to generate carbonyl fluoride under the catalytic action of the catalyst. After the carbonyl fluoride is synthesized into a stable product, the reaction is continued and collected.

[0020] Preferably, the tubular reactor in S1 has a specification of DN25*2000mm.

[0021] Preferably, the diameter of the hole in S1 is 2 to 4 mm.

[0022] Preferably, the high temperature condition in S2 is 200-500°C.

[0023] Preferably, the nitrogen purge time in S2 is 16 to 168 hours; the nitrogen flow rate is 100 to 500 mL / min.

[0024] Preferably, the molar ratio of hexafluoropropylene to oxygen in S3 is 1:1.5-10;

[0025] The flow rate ratio of hexafluoropropylene to oxygen is 1:6-20, and the flow rate of oxygen in S3 is 120-400 mL / min.

[0026] Preferably, the reaction temperature in S3 is 350°C to 500°C.

[0027] Preferably, the time for the carbonyl fluoride to synthesize a stable product in S3 is 48 to 168 hours. Through infrared online analysis and detection, if the infrared spectrum is compared with the standard spectrum, if the comparison is consistent, it is a stable product synthesized by carbonyl fluoride.

[0028] Preferably, the collection temperature in S3 is -80°C.

[0029] The chemical reaction path of the present invention is:

[0030]

[0031] The catalyst in the early stage of the S3 oxidation process of the present invention only plays an initiating role. The carbonyl fluoride generated in the early stage will react with the catalyst to generate metal fluoride. Only after the oxide on the catalyst surface is completely fluorinated will stable carbonyl fluoride be generated. This needs to be carried out under high temperature and anhydrous conditions.

[0032] Beneficial effects of the present invention:

[0033] This scheme uses hexafluoropropylene and oxygen as raw materials and noble metal oxides as catalysts to react to generate carbonyl fluoride products. The crude carbonyl fluoride is filled into a collection cylinder at low temperature. This process has low production costs, simple and easy-to-obtain raw materials, relatively low risk, and can be reacted under normal pressure. The reaction is mild, easy to operate, and has a high reaction yield.

[0034] Compared with other carbonyl fluoride synthesis methods, the present invention does not involve hazardous chemicals such as phosgene and fluorine gas, and has few reaction by-products. In addition, the raw material toxicity of this method is low, hexafluoropropylene can be completely reacted under the condition of excess oxygen, the reaction process is environmentally friendly and simple, and basically no three wastes are generated. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is the infrared spectrum of carbonyl fluoride according to the embodiment of the present invention. DETAILED DESCRIPTION

[0036] Example 1

[0037] Step 1: Add 5 kg of palladium oxide into a DN25*2000 mm reactor, the diameter of the reactor pores is 2 to 4 mm.

[0038] Step 2: Purge with nitrogen at 300° C. for 120 hours at a nitrogen flow rate of 300 mL / min to remove residual moisture in the reactor.

[0039] Step 3: Hexafluoropropylene (20 mL / min) and oxygen (120 mL / min) were introduced into the reactor for reaction. After 168 hours of reaction, stable carbonyl fluoride was generated. Figure 1 .

[0040] 1.5 kg of hexafluoropropylene and 0.48 kg of oxygen were introduced into the reactor at the same feed rate, the hexafluoropropylene flow rate was 20 mL / min, and the oxygen flow rate was 120 mL / min. The reaction was carried out at normal pressure and 500°C for 1.5 hours. The generated carbonyl fluoride product was collected in a collection cylinder at -80°C. A total of 1.69 kg of carbonyl fluoride product was collected, with a purity of 79.6% and a yield of 85.3%.

[0041] Example 2

[0042] Step 1: Add 5 kg of platinum oxide into a DN25*2000 mm reactor, the diameter of the reactor hole is 2 to 4 mm.

[0043] Step 2: Purge with nitrogen at 200° C. for 168 hours at a nitrogen flow rate of 100 mL / min to remove residual moisture in the reactor.

[0044] Step 3: Hexafluoropropylene and oxygen are introduced into the reactor at a flow rate of 20 mL / min and 200 mL / min, and stable carbonyl fluoride is generated after 48 hours of reaction.

[0045] 1.5 kg of hexafluoropropylene and 3.2 kg of oxygen were introduced into the reactor at the same feed rate, the hexafluoropropylene flow rate was 20 mL / min, and the oxygen flow rate was 120 mL / min. The reaction was carried out at normal pressure and 350°C for 2 hours. The generated carbonyl fluoride product was collected in a collection cylinder at -80°C. A total of 1.81 kg of carbonyl fluoride product was collected, with a purity of 66.4% and a yield of 91.4%.

[0046] Example 3

[0047] Step 1: Add 5 kg of ruthenium oxide into a DN25*2000 mm reactor, the diameter of the reactor hole is 2 to 4 mm.

[0048] Step 2: purge with nitrogen at 500°C for 16 hours at a nitrogen flow rate of 500 mL / min to remove residual moisture in the reactor;

[0049] Step 3: Hexafluoropropylene is introduced into the reactor at a flow rate of 20 mL / min and oxygen is introduced at a flow rate of 400 mL / min. After 168 hours of reaction, stable carbonyl fluoride is generated.

[0050] 1.5 kg of hexafluoropropylene and 2.56 kg of oxygen were introduced into the reactor at the same feed rate, the hexafluoropropylene flow rate was 20 mL / min, and the oxygen flow rate was 120 mL / min. The reaction was carried out at normal pressure and 400°C for 1.5 hours. The generated carbonyl fluoride product was collected in a collection cylinder at -80°C. A total of 1.76 kg of carbonyl fluoride product was collected, with a purity of 81.2% and a yield of 88.9%.

[0051] Comparative Example 1

[0052] Step 1: Add 5 kg of palladium oxide into a DN25*2000 mm reactor, the diameter of the reactor pores is 2 to 4 mm.

[0053] Step 2: at 300° C., hexafluoropropylene (20 mL / min) and oxygen (120 mL / min) were introduced into the reactor for reaction. After 168 hours of reaction, stable carbonyl fluoride was generated.

[0054] 1.5 kg of hexafluoropropylene and 0.48 kg of oxygen were introduced into the reactor at the same feed rate, the hexafluoropropylene flow rate was 20 mL / min, and the oxygen flow rate was 120 mL / min. The reaction was carried out at normal pressure and 500°C for 1.5 hours. The generated carbonyl fluoride product was collected in a collection cylinder at -80°C. A total of 1.19 kg of carbonyl fluoride product was collected, with a purity of 76.7% and a yield of 60.1%.

[0055] Comparative Example 2

[0056] Step 1: In a DN25*2000mm reactor without a catalyst, the diameter of the reactor hole is 2 to 4 mm.

[0057] Step 2: purge with nitrogen at 200° C. for 168 hours at a nitrogen flow rate of 100 mL / min to remove residual moisture in the reactor;

[0058] Step 3: Hexafluoropropylene and oxygen are introduced into the reactor at a flow rate of 20 mL / min and 200 mL / min, and no carbonyl fluoride is generated after 48 hours of reaction.

[0059] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing carbonyl fluoride, characterized in that: Hexafluoropropylene and oxygen are used as raw materials, and aeration is conducted into a reactor filled with a catalyst under high temperature conditions. When stable carbonyl fluoride is generated, aeration is continued and then collected. The catalyst is one of palladium oxide, ruthenium oxide, platinum oxide and molybdenum oxide.

2. The method for preparing carbonyl fluoride according to claim 1, characterized in that: The specific steps are as follows: S1, filling the catalyst into the sieve plate with holes inside the tubular reactor and sealing it with a flange head; S2, purging nitrogen into the reactor under high temperature conditions to remove moisture in the reactor and activate the catalyst; S3, hexafluoropropylene and oxygen are introduced into the reactor at a certain flow ratio, and react to generate carbonyl fluoride under the catalytic action of the catalyst. After the carbonyl fluoride is synthesized into a stable product, the reaction is continued and collected.

3. The method for preparing carbonyl fluoride according to claim 2, characterized in that: The specification of the S1 medium tubular reactor is DN25*2000mm.

4. The method for preparing carbonyl fluoride according to claim 2, characterized in that: The diameter of the holes in S1 is 2 to 4 mm.

5. The method for preparing carbonyl fluoride according to claim 2, characterized in that: The medium and high temperature conditions of S2 are 200-500℃.

6. The method for preparing carbonyl fluoride according to claim 2, characterized in that: The duration of nitrogen purge in S2 is 16 to 168 h; the flow rate of nitrogen is 100 to 500 mL / min.

7. The method for preparing carbonyl fluoride according to claim 2, characterized in that: The molar ratio of hexafluoropropylene to oxygen in S3 is 1:1.5-10; The flow rate ratio of hexafluoropropylene to oxygen is 1:6-20, and the flow rate of oxygen in S3 is 120-400 mL / min.

8. The method for preparing carbonyl fluoride according to claim 2, characterized in that: The reaction temperature in S3 is 350°C to 500°C.

9. The method for preparing carbonyl fluoride according to claim 2, characterized in that: The time for the carbonyl fluoride synthesis to produce a stable product in S3 is 48 to 168 hours. Through infrared online analysis and detection, and comparison with the infrared standard spectrum, if the comparison is consistent, it is a stable product of carbonyl fluoride synthesis.

10. The method for preparing carbonyl fluoride according to claim 2, characterized in that: The collection temperature in S3 is -80°C.

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