Bimetal catalyst for synthesizing 1, 1, 1, 2, 3, 3-hexafluoropropane as well as preparation method and application thereof

Abstract

The invention discloses a bimetallic catalyst for synthesizing 1, 1, 1, 2, 3, 3-hexafluoropropane, the bimetallic catalyst is composed of a carrier, organic amine RN loaded on the carrier and metals M1 and M2, the carrier is SiC, the metal M1 is any one of Pt, Pd, Rh, Ru and Ag, and the metal M2 is any one of Mg, Fe, Mn, Ni and Sn; the catalyst comprises the following components in percentage by weight: 0.2-3% of metal M1, 0.1-1% of metal M2, 10-30% of organic amine RN and the balance of a carrier. The invention also discloses a preparation method and application of the catalyst. When the catalyst is used for continuous catalytic synthesis of 1, 1, 1, 2, 3, 3-hexafluoropropane from 1, 1, 1, 2, 3, 3-hexafluoropropylene, the automation degree is high, the yield of a target product is relatively high, and the service life of the catalyst is long.

Description

Technical Field

[0001] The invention belongs to the technical field of 1,1,1,2,3,3-hexafluoropropane preparation, and specifically relates to a bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, and a preparation method and application thereof. Background Art

[0002] 1,1,1,2,3,3-Hexafluoropropane, referred to as HFC-236ea, with the molecular formula CF3-CHF-CH2F, is a colorless, odorless, non-toxic gas with strong solubility, volatility, and good refrigeration performance. It is widely used in commercial and industrial refrigeration equipment and can be used as a refrigerant, fire extinguishing agent, heat transfer medium, gaseous dielectric, bactericide carrier, polymerization medium, particle removal fluid, carrier fluid, polishing agent and abrasive, displacement desiccant and power cycle working fluid.

[0003] 1,1,1,2,3,3-Hexafluoropropane is the raw material for producing 1,1,1,2,3-pentafluoropropene and is the intermediate for producing 1,1,1,2,3-pentafluoropropane or 1,1,1,2-tetrafluoropropene, see patents US5679875A and US8389779B2.

[0004] In the presence of a catalyst composed of metal oxides, 1,1,1,2,2-pentafluoro-3,3-dichloropropane (HCFC-225ca) and / or 1,1,2,2,3-pentafluoro-1,3-dichloropropane (HCFC-225cb) are subjected to a dechlorination and fluorination reaction to obtain at least one tetrafluorochloropropene. Then, the generated tetrafluorochloropropene (1,1,1,2-tetrafluoro-3-chloro-2-propene (HCFO-1224yd), 1,1,2,3-tetrafluoro-1-chloro-2-propene (HCFO-1224ye) and 1,1,2,3-tetrafluoro-3-chloro-1-propene (HCFO-1224yc) are subjected to a fluorination reaction in the presence of a catalyst to produce HFC-236ea, see patent US5532418A. This method is a two-step method for preparing HFC-236ea, and the yield needs to be improved. Summary of the invention

[0005] In view of the defects of the prior art, the present invention provides a bimetallic catalyst for 1,1,1,2,3,3-hexafluoropropane and a preparation method and application thereof. The bimetallic catalyst can synthesize 1,1,1,2,3,3-hexafluoropropane by one-step conversion of hexafluoropropylene.

[0006] A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier, an organic amine RN loaded on the carrier, and metals M1 and M2, the carrier being SiC, the metal M1 being any one of Pt, Pd, Rh, Ru, and Ag, and the metal M2 being any one of Mg, Fe, Mn, Ni, and Sn; the catalyst having the following contents of the components based on 100% by weight: 0.2-3% of metal M1, 0.1-1% of metal M2, 10-30% of organic amine RN, and the balance being the carrier.

[0007] Preferably, the organic amine is any one of diethylenetriamine, triethylenetetramine, morpholine, cyclohexylamine, piperazine, triethylenediamine, N,N-diisopropylethylamine, N,N-diethylethanolamine, and p-phenylenediamine.

[0008] Preferably, the organic amine is any one of diethylenetriamine, morpholine, and p-phenylenediamine. Preferably, the metal M1 is any one of Pt and Pd, and the metal M2 is any one of Ni, Mn and Fe.

[0009] The preparation method of the catalyst comprises the following steps: (1) Dissolving an organic amine in at least one of water, ethanol or tetrahydrofuran according to its solubility to obtain an organic amine solution; adding a carrier thereto, stirring for 2-3 hours, evaporating the solution to dryness, and then drying to obtain RN-SiC; (2) mixing an aqueous solution of a precursor salt of metal M1 and an aqueous solution of a precursor salt of metal M2, adding the RN-SiC obtained in step (1), stirring for 2-3 hours, then standing for 8-10 hours, filtering, and drying to obtain a catalyst precursor; (3) The catalyst precursor is reduced to obtain the catalyst.

[0010] Preferably, the reduction is carried out in a mixed atmosphere of hydrogen and nitrogen at 200-300° C. for 1.5-3 h.

[0011] Preferably, the flow rate of the hydrogen is 50-500 mL / min, and the volume ratio of hydrogen to nitrogen is 1:9.

[0012] Preferably, the concentration of the organic amine solution is 8-12 wt %, and the drying condition is drying at 110-120° C. for 10-15 h.

[0013] A method for continuously catalyzing 1,1,1,2,3,3-hexafluoropropylene to synthesize 1,1,1,2,3,3-hexafluoropropane, which is as follows: loading a catalyst into a fixed bed reactor, replacing the reaction system with nitrogen, then introducing 1,1,1,2,3,3-hexafluoropropylene, introducing hydrogen and nitrogen for hydrogenation reaction, the reaction temperature is 150-300°C, the reaction pressure is 0.1Mpa, and collecting the reaction product; wherein the catalyst is the catalyst according to claim 1.

[0014] Preferably, the molar ratio of hydrogen to 1,1,1,2,3,3-hexafluoropropylene is 10-50, the molar ratio of nitrogen to 1,1,1,2,3,3-hexafluoropropylene is 5-10, and the space velocity of 1,1,1,2,3,3-hexafluoropropylene is 0.05-1 h -1 .

[0015] Advantages of the present invention: (1) The present invention uses an amine functional group to adjust the electronic properties of the carrier, which is beneficial to the desorption of the product on the catalyst and avoids its retention and coating of the active sites of the catalyst, leading to deactivation; (2) The bimetallic catalyst allows the activation of the reactants and the dissociation of H2 to be separated at different active sites, making the catalyst more active, selective and long-lived; (3) The catalyst of the present invention can be applied to the continuous catalytic synthesis of 1,1,1,2,3,3-hexafluoropropylene into 1,1,1,2,3,3-hexafluoropropane. The process has a high degree of continuous automation, low labor intensity, low equipment investment, and less three wastes in the reaction process, thus having good economic and social benefits. The yield of the target product 1,1,1,2,3,3-hexafluoropropane is high and the catalyst life is good. This application provides technical support for later industrial production. DETAILED DESCRIPTION

[0016] Example 1 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine diethylenetriamine loaded on the carrier, and metals Pd and Ni, expressed as PdNi-diethylenetriamine-SiC; the catalyst has the following contents of each component based on 100% by weight: 0.5% metal Pd, 0.1% Ni, 10% diethylenetriamine, and the balance being the carrier; The preparation method of the catalyst comprises the following steps: (1) Prepare a 100 g, 10 wt% diethylenetriamine ethanol solution, add 90 g SiC carrier thereto, immerse and stir for 2 h, evaporate the solution to dryness, and then dry at 120 ° C for 12 h to obtain diethylenetriamine-SiC; (2) Dissolve 1.38 g of sodium chloropalladate in water to obtain solution B, dissolve 0.50 g of nickel nitrate hexahydrate in water to obtain solution C, add solution C to solution B, immerse the diethylenetriamine-SiC obtained in step (1) therein, stir for 2 h, then let stand for 8 h, filter, and dry at 120 ° C for 12 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tubular furnace and reduced at 300° C. for 2 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 50 mL / min.

[0017] Example 2 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine diethylenetriamine loaded on the carrier, and metals Pt and Ni, expressed as PtNi-diethylenetriamine-SiC; the catalyst has the following contents of each component based on 100% by weight: 0.5% of metal Pt, 0.1% of Ni, 10% of diethylenetriamine, and the balance being the carrier; The preparation method of the catalyst comprises the following steps: (1) Prepare a 100 g, 10 wt% diethylenetriamine ethanol solution, add 90 g SiC carrier thereto, immerse and stir for 2 h, evaporate the solution to dryness, and then dry at 120 ° C for 12 h to obtain diethylenetriamine-SiC; (2) Dissolve 1.05 g of chloroplatinic acid in water to obtain solution B, dissolve 0.50 g of nickel nitrate hexahydrate in water to obtain solution C, add solution C to solution B, immerse the diethylenetriamine-SiC obtained in step (1) therein, stir for 2 h, then let stand for 8 h, filter, and dry at 120 ° C for 12 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tubular furnace and reduced at 300° C. for 2 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 50 mL / min.

[0018] Example 3 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine diethylenetriamine loaded on the carrier, and metals Pd and Ni, expressed as PdNi-diethylenetriamine-SiC; the catalyst has the following contents of each component based on 100% by weight: 3% metal Pd, 0.1% Ni, 10% diethylenetriamine, and the balance being the carrier; The preparation method of the catalyst comprises the following steps: (1) Prepare a 100 g, 10 wt% diethylenetriamine ethanol solution, add 90 g SiC carrier thereto, immerse and stir for 2 h, evaporate the solution to dryness, and then dry at 120 ° C for 12 h to obtain diethylenetriamine-SiC; (2) 8.29 g of sodium chloropalladate was dissolved in water to obtain solution B, 0.50 g of nickel nitrate hexahydrate was dissolved in water to obtain solution C, solution C was added to solution B, diethylenetriamine-SiC obtained in step (1) was immersed therein, stirred for 2 h, then allowed to stand for 8 h, filtered, and dried at 120 ° C for 12 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tubular furnace and reduced at 300° C. for 2 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 50 mL / min.

[0019] Example 4 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine p-phenylenediamine loaded on the carrier, and metals Pd and Ni, expressed as PdNi-p-phenylenediamine-SiC; the catalyst has the following contents of each component based on 100% by weight: 0.5% metal Pd, 0.1% Ni, 10% p-phenylenediamine, and the remainder being the carrier; The preparation method of the catalyst comprises the following steps: (1) preparing a 100 g ethanol solution of 10 wt% p-phenylenediamine, adding 90 g SiC carrier thereto, immersing, stirring for 2 h, evaporating the solution to dryness, and then drying at 120 ° C for 12 h to obtain p-phenylenediamine-SiC; (2) Dissolve 1.38 g of sodium chloropalladate in water to obtain solution B, dissolve 0.50 g of nickel nitrate hexahydrate in water to obtain solution C, add solution C to solution B, immerse the p-phenylenediamine-SiC obtained in step (1) therein, stir for 2 h, then let stand for 8 h, filter, and dry at 120 ° C for 12 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tubular furnace and reduced at 300° C. for 2 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 50 mL / min.

[0020] Example 5 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine diethylenetriamine loaded on the carrier, and metals Pd and Mn, expressed as PdMn-diethylenetriamine-SiC; the catalyst has the following contents of each component based on 100% by weight: 0.5% metal Pd, 0.1% Mn, 10% diethylenetriamine, and the balance being the carrier; The preparation method of the catalyst comprises the following steps: (1) preparing a 100 g ethanol solution of 10 wt% diethylenetriamine, adding 90 g SiC carrier thereto, immersing, stirring for 2 h, evaporating the solution to dryness, and then drying at 120 ° C for 12 h to obtain diethylenetriamine-SiC; (2) Dissolve 1.38 g of sodium chloropalladate in water to obtain solution B, dissolve 0.32 g of manganese nitrate in water to obtain solution C, add solution C to solution B, immerse the diethylenetriamine-SiC obtained in step (1) therein, stir for 2 h, then let stand for 8 h, filter, and dry at 120 ° C for 12 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tubular furnace and reduced at 300° C. for 2 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 50 mL / min.

[0021] Example 6 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine diethylenetriamine loaded on the carrier, and metals Pd and Fe, expressed as PdFe-diethylenetriamine-SiC; the catalyst has the following contents of each component based on 100% by weight: 0.5% metal Pd, 0.1% Fe, 10% diethylenetriamine, and the balance being the carrier; The preparation method of the catalyst comprises the following steps: (1) preparing a 100 g ethanol solution of 10 wt% diethylenetriamine, adding 90 g SiC carrier thereto, immersing, stirring for 2 h, evaporating the solution to dryness, and then drying at 120 ° C for 12 h to obtain diethylenetriamine-SiC; (2) Dissolve 1.38 g of sodium chloropalladate in water to obtain solution B, dissolve 0.72 g of ferric nitrate nonahydrate in water to obtain solution C, add solution C to solution B, immerse the diethylenetriamine-SiC obtained in step (1) therein, stir for 2 h, then let stand for 8 h, filter, and dry at 120 ° C for 12 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tubular furnace and reduced at 300° C. for 2 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 50 mL / min.

[0022] Example 7 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine morpholine supported on the carrier, and metals Rh and Mg, expressed as RhMg-morpholine-SiC; the catalyst has the following contents of each component based on 100% by weight: 0.5% metal Rh, 1% Mg, 30% morpholine, and the balance being the carrier; The preparation method of the catalyst comprises the following steps: (1) preparing 375 g of an 8 wt% morpholine aqueous solution, adding 70 g of a SiC carrier thereto, immersing the carrier, stirring for 3 h, evaporating the solution to dryness, and then drying at 110 °C for 15 h to obtain morpholine-SiC; (2) Dissolve 1.28 g of rhodium trichloride trihydrate in water to obtain solution B, dissolve 6.10 g of magnesium nitrate in water to obtain solution C, add solution C to solution B, immerse the morpholine-SiC obtained in step (1) therein, stir for 3 h, then let stand for 10 h, filter, and dry at 110 ° C for 15 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tube furnace and reduced at 200° C. for 3 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 500 mL / min.

[0023] Example 8 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine cyclohexylamine loaded on the carrier, and metals Ru and Sn, expressed as RuSn-cyclohexylamine-SiC; the catalyst has the following contents of each component based on 100% by weight: 0.5% of metal Ru, 0.5% of Sn, 20% of cyclohexylamine, and the balance of the carrier; The preparation method of the catalyst comprises the following steps: (1) preparing 167 g of an aqueous solution of 12 wt% cyclohexylamine, adding 80 g of a SiC carrier thereto, immersing the carrier, stirring for 2 h, evaporating the solution to dryness, and then drying at 120 ° C. for 10 h to obtain cyclohexylamine-SiC; (2) Dissolve 1.03 g of ruthenium trichloride in water to obtain solution B, dissolve 1.48 g of tin tetrachloride pentahydrate in water to obtain solution C, add solution C to solution B, immerse the cyclohexylamine-SiC obtained in step (1) therein, stir for 3 h, then let stand for 10 h, filter, and dry at 120° C. for 10 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tube furnace and reduced at 300° C. for 1.5 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 500 mL / min.

[0024] Example 9 A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, the bimetallic catalyst comprising a carrier SiC, an organic amine N,N-diisopropylethylamine loaded on the carrier, and metals Ag and Ni, expressed as AgNi-N,N-diisopropylethylamine-SiC; the catalyst has the following contents of each component based on 100% by weight: 0.5% metal Ag, 0.1% Ni, 10% N,N-diisopropylethylamine, and the balance being the carrier; The preparation method of the catalyst comprises the following steps: (1) preparing a 100 g, 10 wt% N,N-diisopropylethylamine aqueous solution, adding 90 g of SiC carrier thereto, immersing, stirring for 2 h, evaporating the solution to dryness, and then drying at 120 ° C for 10 h to obtain N,N-diisopropylethylamine-SiC; (2) Dissolve 0.79 g of silver nitrate in water to obtain solution B, dissolve 0.50 g of nickel nitrate hexahydrate in water to obtain solution C, add solution C to solution B, immerse the N,N-diisopropylethylamine-SiC obtained in step (1), stir for 2 h, then let stand for 8 h, filter, and dry at 120 ° C for 10 h to obtain a catalyst precursor; (3) The catalyst precursor is transferred to a tube furnace and reduced at 300° C. for 2 h in a H2 / N2 mixed atmosphere with a volume ratio of 1:9 to obtain the catalyst; wherein the flow rate of H2 is 100 mL / min.

[0025] Catalyst performance evaluation 1. Catalytic performance evaluation The catalyst is loaded into a quartz tube of a fixed bed reactor, the reaction system is replaced with nitrogen, 1,1,1,2,3,3-hexafluoropropylene is introduced, hydrogen and nitrogen are introduced for hydrogenation reaction, the reaction temperature is 150-300°C, the reaction pressure is 0.1Mpa, the reaction product is collected and sent to GC for detection; wherein the molar ratio of hydrogen to 1,1,1,2,3,3-hexafluoropropylene is 10-50, the molar ratio of nitrogen to 1,1,1,2,3,3-hexafluoropropylene is 5-10, and the space velocity of 1,1,1,2,3,3-hexafluoropropylene is 0.05-1 h -1 , and the reaction was continued for 500 h; the specific reaction conditions and reaction results are shown in Table 1.

[0026] Table 1 Specific reaction conditions and results catalyst Temperature ℃ Hydrogen-olefin molar ratio Nitride molar ratio <![CDATA[Air speed h -1 > Yield % Example 1 150 50 5 0.05 63 Example 1 250 15 5 0.05 74 Example 1 300 15 5 1 78 Example 2 250 15 5 0.05 55 Example 2 250 20 5 0.20 58 Example 3 180 10 5 0.15 68 Example 4 250 15 5 0.05 82 Example 5 250 15 5 0.05 67 Example 6 250 15 5 0.05 64 Example 7 250 15 5 0.20 61 Example 8 250 15 7 0.15 66 Example 9 250 15 10 0.10 63 2. Catalyst stability evaluation In the above reaction, the catalyst of Example 1 was used, the reaction temperature was 300°C, the pressure was 0.1 MPa, the hydrogen-olefin molar ratio was 15, the nitrogen-olefin molar ratio was 5, and the space velocity was 1 h -1 The yields at different reaction times are shown in Table 2.

[0027] Table 2 Reaction results of the catalyst described in Example 1 at different reaction times Time Yield % 500 78 550 78 600 76 650 75 800 73 1000 70

Claims

1. A bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane, characterized in that: The bimetallic catalyst is composed of a carrier, an organic amine RN loaded on the carrier, and metals M1 and M2, wherein the carrier is SiC, the metal M1 is any one of Pt, Pd, Rh, Ru, and Ag, and the metal M2 is any one of Mg, Fe, Mn, Ni, and Sn; the content of each component of the catalyst is as follows, based on 100% by weight: metal M1 0.2-3%, metal M2 0.1-1%, organic amine RN 10-30%, and the balance is the carrier.

2. The bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane according to claim 1, characterized in that: The organic amine is any one of diethylenetriamine, triethylenetetramine, morpholine, cyclohexylamine, piperazine, triethylenediamine, N,N-diisopropylethylamine, N,N-diethylethanolamine and p-phenylenediamine.

3. The bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane according to claim 2, characterized in that: The organic amine is any one of diethylenetriamine, morpholine and p-phenylenediamine.

4. The bimetallic catalyst for synthesizing 1,1,1,2,3,3-hexafluoropropane according to claim 3, characterized in that: The metal M1 is any one of Pt and Pd, and the metal M2 is any one of Ni, Mn and Fe.

5. The method for preparing the catalyst according to claim 1, characterized in that: The following steps are involved: (1) Dissolving an organic amine in at least one of water, ethanol or tetrahydrofuran according to its solubility to obtain an organic amine solution; adding a carrier thereto, stirring for 2-3 hours, evaporating the solution to dryness, and then drying to obtain RN-SiC; (2) mixing an aqueous solution of a precursor salt of metal M1 and an aqueous solution of a precursor salt of metal M2, adding the RN-SiC obtained in step (1), stirring for 2-3 hours, then standing for 8-10 hours, filtering, and drying to obtain a catalyst precursor; (3) The catalyst precursor is reduced to obtain the catalyst.

6. The method for preparing the catalyst according to claim 5, characterized in that: The reduction is carried out in a mixed atmosphere of hydrogen and nitrogen at 200-300° C. for 1.5-3 h.

7. The method for preparing the catalyst according to claim 6, characterized in that: The flow rate of the hydrogen is 50-500 mL / min, and the volume ratio of hydrogen to nitrogen is 1:

9.

8. The method for preparing the catalyst according to claim 7, characterized in that: The concentration of the organic amine solution is 8-12 wt %, and the drying condition is drying at 110-120° C. for 10-15 hours.

9. A method for continuously catalyzing 1,1,1,2,3,3-hexafluoropropylene to synthesize 1,1,1,2,3,3-hexafluoropropane, characterized in that: The details are as follows: loading the catalyst into a fixed bed reactor, replacing the reaction system with nitrogen, then introducing 1,1,1,2,3,3-hexafluoropropylene, introducing hydrogen and nitrogen for hydrogenation reaction, the reaction temperature is 150-300°C, the reaction pressure is 0.1Mpa, and collecting the reaction products; wherein the catalyst is the catalyst according to claim 1.

10. The method for catalyzing 1,1,1,2,3,3-hexafluoropropylene to synthesize 1,1,1,2,3,3-hexafluoropropane according to claim 9, characterized in that: The molar ratio of hydrogen to 1,1,1,2,3,3-hexafluoropropylene is 10-50, the molar ratio of nitrogen to 1,1,1,2,3,3-hexafluoropropylene is 5-10, and the space velocity of 1,1,1,2,3,3-hexafluoropropylene is 0.05-1 h -1 .