阅读说明：本技术 全氟己酮生产过程中副产物2-氯-1,1,1,3,3,3-六氟丙烷的资源化利用方法 (Resource utilization method of byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in production process of perfluorohexanone ) 是由 韩文锋 陶杨 刘兵 陈爱民 于 2020-12-31 设计创作，主要内容包括：本发明公开了全氟己酮生产过程中副产物2-氯-1,1,1,3,3,3-六氟丙烷的资源化利用方法,过程为：在反应釜中加入甲醇钠、溶剂和催化剂,搅拌升温至反应温度后,搅拌下通入2-氯-1,1,1,3,3,3-六氟丙烷气体进行反应,反应结束后冷却、出料、精馏,即得到1,1,1,3,3,3-六氟异丙基甲基醚。本发明成功的将全氟己酮生产过程中的副产物2-氯-1,1,1,3,3,3-六氟丙烷资源化利用,并转化为具有高附加值的氢氟醚产品。同时1,1,1,3,3,3-六氟异丙基甲基醚的合成过程不使用强碱,工艺简单、环保,反应条件温和,成本低、产品质量好,实现了绿色化学的工艺生产,具有非常好的工业应用前景。(The invention discloses a resource utilization method of a byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in a perfluorohexanone production process, which comprises the following steps: adding sodium methoxide, a solvent and a catalyst into a reaction kettle, stirring and heating to a reaction temperature, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas while stirring for reaction, cooling after the reaction is finished, discharging and rectifying to obtain the 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether. The method successfully utilizes the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of the perfluorohexanone as a resource and converts the byproduct into a hydrofluoroether product with high added value. Meanwhile, strong base is not used in the synthesis process of the 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether, the process is simple and environment-friendly, the reaction condition is mild, the cost is low, the product quality is good, the green chemical process production is realized, and the method has a very good industrial application prospect.)

1. A resource utilization method of byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in a perfluorohexanone production process is characterized in that sodium methoxide, a solvent and a catalyst are added into a reaction kettle, the mixture is stirred and heated to a reaction temperature, 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas is introduced into the reaction kettle under stirring for reaction, and after the reaction is finished, the mixture is cooled, discharged and rectified to obtain 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether.

2. The method of claim 1, wherein the solvent is one of acetonitrile, methanol, and N, N-dimethylformamide, and the catalyst is MF (MF)₂Or doped with nitrogen carbon, said MF₂M in (A) represents one of Ba, Sr and Ca.

3. The method of claim 2, wherein the MF is a method for recycling 2-chloro-1, 1,1,3,3, 3-hexafluoropropane produced as a byproduct in a perfluorohexanone production process₂The preparation method comprises the following steps: dissolving M metal salt and a fluorine source in deionized water, stirring at room temperature for 0.5-1h to form a precipitate, standing and aging for 1-2h, then performing suction filtration, washing, drying, and finally calcining at the temperature of 350-450 ℃ for 3-5h in a muffle furnace in an air atmosphere to obtain the MF (MF)₂A catalyst.

4. The method of claim 3, wherein the fluorine source is ammonium fluoride (MF), namely, MF₂The molar ratio of M metal in (b) to F in the fluorine source is 1: 2-3, preferably 1: 2.2.

5. The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the perfluorohexanone production process according to claim 2, characterized in that the preparation process of the nitrogen-doped carbon catalyst is as follows: mixing coconut shell activated carbon and melamine according to the mass ratio of 1: 1.5-3, adding the mixture into an alcohol solvent, stirring for 10-15h at the temperature of 50-70 ℃, filtering, drying, and finally calcining for 3-5h at the temperature of 650-750 ℃ in a muffle furnace under the air atmosphere to obtain the nitrogen-doped carbon catalyst.

6. The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the perfluorohexanone production process according to claim 1, characterized in that the molar ratio of sodium methoxide to 2-chloro-1, 1,1,3,3, 3-hexafluoropropane is 3-20: 1, preferably 6.5-10: 1; the mass ratio of the 2-chloro-1, 1,1,3,3, 3-hexafluoropropane to the solvent is 1-10: 1, preferably 1-3: 1.

7. The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the perfluorohexanone production process according to claim 1, characterized in that the mass of the catalyst is 1% -10% of the mass of the 2-chloro-1, 1,1,3,3, 3-hexafluoropropane.

8. The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the perfluorohexanone production process according to claim 1, characterized in that the reaction temperature is controlled to be 30-150 ℃; and continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas in the reaction process, keeping the reaction pressure in the reaction kettle between 0.1 and 1MPa, stopping introducing the 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas, and continuing to react for 2 to 12 hours, namely finishing the reaction.

Technical Field

The invention relates to a resource utilization method of a byproduct, namely 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in a perfluorohexanone production process.

Background

The perfluorohexanone is a novel halon substitute, has an ODP value of 0 and a GWP value of 1, belongs to a green environment-friendly compound, and has almost zero harm to the environment and human bodies; the water-based solar heat collector is colorless liquid at normal temperature, is easy to vaporize, is easy to store at normal temperature and normal pressure, has evaporation heat of 1/25 of water only, and has strong heat absorption capacity. Can be used for physical fire extinguishing, has excellent fire extinguishing performance and is suitable for protecting precise and valuable equipment. When used as a clean fire extinguishing agent, the fire extinguishing agent does not belong to dangerous goods, does not leave residues after release, and is convenient to transport.

Because the generation of a by-product 2-chloro-1, 1,1,3,3, 3-hexafluoropropane can not be avoided in the process of producing the perfluorohexanone, the current main treatment mode of the 2-chloro-1, 1,1,3,3, 3-hexafluoropropane is incineration treatment, but the environmental pollution is aggravated, and the production cost of the perfluorohexanone is increased. Meanwhile, the hydrofluoroether is used as a novel and efficient fluorine-containing product, has an ODP value of 0 and a very low GWP value, and can be used as a cleaning agent for precise electronic devices. And the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the process of producing the perfluorohexanone can be transferred into a 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether product with high added value only by simple dechlorination.

Therefore, the development of a process route for resource utilization of the byproduct, namely 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of the perfluorohexanone is very important.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a resource utilization method of byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone. The method successfully utilizes the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of the perfluorohexanone as a resource and converts the byproduct into a hydrofluoroether product with high added value. Meanwhile, strong base is not used in the synthesis process of the 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether, the process is simple and environment-friendly, the reaction condition is mild, the cost is low, the product quality is good, the green chemical process production is realized, and the method has a very good industrial application prospect.

The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone is characterized in that sodium methoxide, a solvent and a catalyst are added into a reaction kettle, the mixture is stirred and heated to the reaction temperature, 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas is introduced into the reaction kettle under stirring for reaction, and after the reaction is finished, the mixture is cooled, discharged and rectified to obtain the 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether.

The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone is characterized in that the solvent is one of acetonitrile, methanol and N, N-dimethylformamide, and the catalyst is MF₂Or doped with nitrogen carbon, said MF₂M in (A) represents one of Ba, Sr and Ca.

The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone is characterized in that the MF is a resource utilization method of₂The preparation method comprises the following steps: dissolving M metal salt and a fluorine source in deionized water, stirring at room temperature for 0.5-1h to form a precipitate, standing and aging for 1-2h, then performing suction filtration, washing, drying, and finally calcining at the temperature of 350-450 ℃ for 3-5h in a muffle furnace in an air atmosphere to obtain the MF (MF)₂A catalyst.

The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone is characterized in that the fluorine source is ammonium fluoride and MF₂The molar ratio of M metal in (b) to F in the fluorine source is 1: 2-3, preferably 1: 2.2.

The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone is characterized in that the preparation process of the nitrogen-doped carbon catalyst comprises the following steps: mixing coconut shell activated carbon and melamine according to the mass ratio of 1: 1.5-3, adding the mixture into an alcohol solvent, stirring for 10-15h at the temperature of 50-70 ℃, filtering, drying, and finally calcining for 3-5h at the temperature of 650-750 ℃ in a muffle furnace under the air atmosphere to obtain the nitrogen-doped carbon catalyst.

The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone is characterized in that the molar ratio of sodium methoxide to 2-chloro-1, 1,1,3,3, 3-hexafluoropropane is 3-20: 1, preferably 6.5-10: 1; the mass ratio of the 2-chloro-1, 1,1,3,3, 3-hexafluoropropane to the solvent is 1-10: 1, preferably 1-3: 1.

The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone is characterized in that the mass of the catalyst is 1% -10% of that of the 2-chloro-1, 1,1,3,3, 3-hexafluoropropane.

The resource utilization method of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the production process of perfluorohexanone is characterized in that the reaction temperature is controlled to be 30-150 ℃; and continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas in the reaction process, keeping the reaction pressure in the reaction kettle between 0.1 and 1MPa, stopping introducing the 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas, and continuing to react for 2 to 12 hours, namely finishing the reaction.

By adopting the technology, compared with the prior art, the invention has the beneficial effects that:

1) the method carries out resource utilization on the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane in the process of producing the perfluorohexanone, converts the 2-chloro-1, 1,1,3,3, 3-hexafluoropropane with low additional value into 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with high additional value, and increases the economic benefit of the perfluorohexanone process route. Meanwhile, the treatment cost of the byproduct 2-chloro-1, 1,1,3,3, 3-hexafluoropropane is reduced, the pollution of the byproduct to the environment is reduced, and the green chemical process concept is realized.

2) The adopted catalysts are all BaF₂、SrF₂、CaF₂And the nitrogen-doped carbon and other cheap catalysts are cheap and easy to obtain, have very good selectivity and greatly reduce the production cost. Meanwhile, the process route does not use strong alkali, does not cause the problem of environmental pollution, is a green and environment-friendly process route, and has good industrial application prospect.

Detailed Description

The present invention is further illustrated by the following examples, which should not be construed as limiting the scope of the invention.

Comparative example 1

Preparation of MgF₂Catalyst: weighing 93.24g of magnesium nitrate and 53g of ammonium fluoride, dissolving the weighed magnesium nitrate and ammonium fluoride in 300ml of deionized water, stirring at room temperature for 0.5h to form a precipitate, standing and aging for 1h, performing suction filtration and washing, drying at 120 ℃ for 12h, and roasting at 400 ℃ for 4h in a muffle furnace in an air atmosphere to obtain MgF₂A catalyst.

400g of sodium methoxide, 40g of acetonitrile and 6.2g of MgF are sequentially added into a 5L stainless steel autoclave with mechanical stirring, electric heating, thermocouple and pressure display₂And (2) sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 30 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. After introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, the introduction of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane was stopped, and the reaction was continued for 2 hours. After the reaction is finished, cooling, discharging and rectifying to obtain 48g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 99.1 percent and the yield of 12.5 percent.

The experiment of comparative example 1 was less effective due to MgF₂The acidity is too strong, C-F can be broken to generate a large amount of byproducts, so that the yield of the target product is low.

Comparative example 2

Selecting common coconut shell activated carbon as a catalyst, sequentially adding 800g of sodium methoxide, 300g of acetonitrile and 4.8g of the common coconut shell activated carbon catalyst into a 5L stainless steel autoclave with mechanical stirring, electric heating, thermocouple and pressure display, sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 100 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flowmeter, starting reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. And stopping introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, and continuing to react for 8 hours. After the reaction is finished, cooling, discharging and rectifying to obtain 13.8g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 97.2 percent and the yield of 3.6 percent.

The experiment of comparative example 2 is poor in effect, because the common coconut shell activated carbon is too weak in acidity and cannot hydrolyze and break C-Cl bonds, so that the yield of the target product is low.

Example 1

Preparation of BaF₂Catalyst: weighing 59.6g of barium nitrate and 18.6g of ammonium fluoride, dissolving the weighed barium nitrate and ammonium fluoride in 300ml of deionized water, stirring at room temperature for 0.5h to form a precipitate, standing and aging for 1h, performing suction filtration and washing, drying at 120 ℃ for 12h, and roasting at 400 ℃ for 4h in a muffle furnace in an air atmosphere to obtain BaF₂A catalyst.

400g of sodium methoxide, 40g of acetonitrile and 17.5g of BaF were sequentially added to a 5L stainless steel autoclave with mechanical stirring, electrical heating, thermocouple and pressure indication₂And (2) sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 30 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. After introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, the introduction of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane was stopped, and the reaction was continued for 2 hours. After the reaction is finished, cooling, discharging and rectifying to obtain 245g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 99.3 percent and the yield of 63.7 percent.

Example 2

Preparation of SrF₂Catalyst: weighing 67.4g of strontium nitrate and 26g of ammonium fluoride, dissolving the weighed strontium nitrate and ammonium fluoride in 300ml of deionized water, stirring at room temperature for 0.5h to form a precipitate, standing and aging for 1h, performing suction filtration and washing, drying at 120 ℃ for 12h, and roasting at 400 ℃ for 4h in a muffle furnace in an air atmosphere to obtain SrF₂A catalyst.

Sequentially adding into a 5L stainless steel autoclave with mechanical stirring, electric heating, thermocouple and pressure display2000g of sodium methoxide, 400g of methanol, 25g of SrF₂And (2) sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 150 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. After introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, the introduction of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane was stopped, and the reaction was continued for 12 hours. After the reaction is finished, cooling, discharging and rectifying to obtain 378g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 99.1 percent and the yield of 97.7 percent.

Example 3

Preparation of CaF₂Catalyst: weighing 121g of calcium nitrate tetrahydrate and 41.8g of ammonium fluoride, dissolving the weighed calcium nitrate tetrahydrate and ammonium fluoride in 300ml of deionized water, stirring at room temperature for 0.5h to form a precipitate, standing and aging for 1h, then performing suction filtration and washing, drying at 120 ℃ for 12h, and then roasting at 400 ℃ for 4h in a muffle furnace under an air atmosphere to obtain CaF₂A catalyst.

1000g of sodium methoxide, 200g N, N-dimethylformamide and 23.4g of CaF were placed in succession in a 5L stainless steel autoclave with mechanical stirring, electrical heating, thermocouple and pressure indication₂And (2) sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 60 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. After introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, the introduction of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane was stopped, and the reaction was continued for 6 hours. After the reaction is finished, cooling, discharging and rectifying to obtain 313g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 99.2 percent and the yield of 81.6 percent.

Example 4

Preparing a nitrogen-doped carbon catalyst: adding 10g of common coconut shell activated carbon and 20g of melamine into 120ml of methanol, stirring for 12h in a water bath at 60 ℃, then filtering, drying the obtained solid for 12h at 110 ℃, and roasting for 3h at 700 ℃ in a muffle furnace under the air atmosphere to obtain the nitrogen-doped carbon catalyst.

Sequentially adding 800g of sodium methoxide, 300g of acetonitrile and 4.8g of nitrogen-doped carbon catalyst into a 5L stainless steel autoclave with mechanical stirring, electric heating, a thermocouple and pressure display, sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 100 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting the reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. And stopping introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, and continuing to react for 8 hours. After the reaction is finished, the mixture is cooled, discharged and rectified to obtain 321g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 99.4 percent and the yield of 83.5 percent.

Example 5

Preparation of CaF₂Catalyst: weighing 121g of calcium nitrate tetrahydrate and 41.8g of ammonium fluoride, dissolving the weighed calcium nitrate tetrahydrate and ammonium fluoride in 300ml of deionized water, stirring at room temperature for 0.5h to form a precipitate, standing and aging for 1h, then performing suction filtration and washing, drying at 120 ℃ for 12h, and then roasting at 400 ℃ for 4h in a muffle furnace under an air atmosphere to obtain CaF₂A catalyst.

1200g of sodium methoxide, 250g N, N-dimethylformamide and 15.6g of CaF are added in succession to a 5L stainless steel autoclave with mechanical stirring, electrical heating, thermocouple and pressure indication₂And (2) sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 90 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. After introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, the introduction of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane was stopped, and the reaction was continued for 10 hours. After the reaction is finished, cooling, discharging and rectifying to obtain 337g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 99.3 percent and the yield of 87.2 percent.

Example 6

Preparation of BaF₂Catalyst: weighing 59.6g of barium nitrate and 18.6g of ammonium fluoride, dissolving the weighed barium nitrate and ammonium fluoride in 300ml of deionized water, stirring at room temperature for 0.5h to form a precipitate, standing and aging for 1h, performing suction filtration and washing, drying at 120 ℃ for 12h, and roasting at 400 ℃ for 4h in a muffle furnace in an air atmosphere to obtain BaF₂A catalyst.

1000g of sodium methoxide, 200g of acetonitrile and 35g of BaF were sequentially added to a 5L stainless steel autoclave with mechanical stirring, electrical heating, thermocouple and pressure indication₂And (2) sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 120 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. After introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, the introduction of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane was stopped, and the reaction was continued for 9 hours. After the reaction is finished, cooling, discharging and rectifying to obtain 352g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 99.7 percent and the yield of 91.3 percent.

Example 7

Preparation of SrF₂Catalyst: weighing 67.4g of strontium nitrate and 26g of ammonium fluoride, dissolving the weighed strontium nitrate and ammonium fluoride in 300ml of deionized water, stirring at room temperature for 0.5h to form a precipitate, standing and aging for 1h, performing suction filtration and washing, drying at 120 ℃ for 12h, and roasting at 400 ℃ for 4h in a muffle furnace in an air atmosphere to obtain SrF₂A catalyst.

800g of sodium methoxide, 300g of methanol and 37.5g of SrF are sequentially added into a 5L stainless steel autoclave with mechanical stirring, electric heating, thermocouple and pressure display₂Sealing the feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 100 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process and maintaining the interior of the autoclaveThe pressure is between 0.5 and 0.8 MPa. And stopping introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, and continuing to react for 8 hours. After the reaction is finished, cooling, discharging and rectifying to obtain 358g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with the purity of 99.6 percent and the yield of 92.6 percent.

Example 8

Preparing a nitrogen-doped carbon catalyst: adding 10g of common coconut shell activated carbon and 20g of melamine into 120ml of methanol, stirring for 12h in a water bath at 60 ℃, then filtering, drying the obtained solid for 12h at 110 ℃, and roasting for 3h at 700 ℃ in a muffle furnace under the air atmosphere to obtain the nitrogen-doped carbon catalyst.

Adding 1000g of sodium methoxide, 160g N, N-dimethylformamide and 4.8g of nitrogen-doped carbon catalyst into a 5L stainless steel autoclave with mechanical stirring, electric heating, a thermocouple and pressure display in sequence, sealing a feed inlet of the stainless steel autoclave after the raw materials are added, starting stirring, starting heating, controlling the reaction temperature to be 130 ℃, introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane gas into the autoclave through a gas mass flow meter, starting the reaction, continuously introducing 2-chloro-1, 1,1,3,3, 3-hexafluoropropane during the reaction process, and maintaining the pressure in the autoclave to be 0.5-0.8 MPa. After introducing 400g of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane, the introduction of 2-chloro-1, 1,1,3,3, 3-hexafluoropropane was stopped, and the reaction was continued for 12 hours. After the reaction, the mixture was cooled, discharged and rectified to obtain 276g of 1,1,1,3,3, 3-hexafluoroisopropyl methyl ether with a purity of 99.3% and a yield of 71.7%.

The statements in this specification merely set forth a list of implementations of the inventive concept and the scope of the present invention should not be construed as limited to the particular forms set forth in the examples.