A catalyst for the continuous synthesis of 2-chloro-3,3,3-trifluoropropene from 1,1,2,3-tetrachloropropene and applications thereof

Abstract

This invention discloses a catalyst for the continuous synthesis of 2-chloro-3,3,3-trifluoropropene from 1,1,2,3-tetrachloropropene and its application. The catalyst uses γ-alumina as a support and is loaded with copper, nickel, and palladium. Based on the mass of the support (100%), the loading of copper is 5%–22%, the loading of nickel is 2%–10%, and the loading of palladium is 1%–5%. The preparation method employs a conventional impregnation method, followed by impregnation, calcination, and reduction, and then further fluorination with hydrogen fluoride. This catalyst, used in the synthesis of 2-chloro-3,3,3-trifluoropropene from 1,1,2,3-tetrachloropropene, exhibits high feed conversion rate and product selectivity, and maintains stable catalytic activity over long-term operation. It significantly improves the preparation efficiency of 2-chloro-3,3,3-trifluoropropene and possesses characteristics such as high activity, high selectivity, long service life, low preparation cost, ease of preparation, and low pollution, aligning with the principles of green chemistry.

Description

Technical Field

[0001] This invention belongs to the field of 2-chloro-3,3,3-trifluoropropylene preparation technology, specifically relating to a catalyst for the continuous synthesis of 2-chloro-3,3,3-trifluoropropylene from 1,1,2,3-tetrachloropropylene and its application. Background Technology

[0002] 2-Chloro-3,3,3-trifluoropropene has significant practical value, especially as an intermediate in the synthesis of 2,3,3,3-tetrafluoropropene (HFC-1234yf). Due to its low global warming potential (GWP=4) and low ozone depletion rate, 2,3,3,3-tetrafluoropropene is considered an effective refrigerant and a potential replacement for 1,1,1,2-tetrafluoroethane. Furthermore, 2,3,3,3-tetrafluoropropene has other applications, such as serving as a heat transfer medium, a foaming agent, a sterilization carrier, and a polishing compound. Given its significant commercial and environmental potential, the rapid and efficient preparation of 2-chloro-3,3,3-trifluoropropene has become a hotly debated topic in the chemical community.

[0003] The preparation of 2-chloro-3,3,3-trifluoropropene requires a catalyst with not only a long lifespan but also high activity and selectivity to significantly shorten the reaction time and increase the reaction rate. The previously reported La / F-Cr2O3 catalyst for the synthesis of 2-chloro-3,3,3-trifluoropropene from 1,1,2,3-tetrachloropropene showed a conversion rate decline to 98% after 96 hours, indicating low conversion and poor stability. Fe-based fluorination catalysts have been reported for the gas-phase fluorination of 2-chloro-3,3,3-trifluoropropene from 1,1,2,3-tetrachloropropene. After a single-pass continuous reaction of 1200 hours, the conversion of 1,1,2,3-tetrachloropropene was greater than 99%, and the selectivity of 2-chloro-3,3,3-trifluoropropene was greater than 94%. However, this catalyst still suffers from rapid degradation over long-term use. Summary of the Invention

[0004] The purpose of this invention is to provide a catalyst for the efficient preparation of 2-chloro-3,3,3-trifluoropropene from 1,1,2,3-tetrachloropropene. This catalyst has the characteristics of high activity, long lifetime, high selectivity and easy preparation, which greatly improves the preparation efficiency of 2-chloro-3,3,3-trifluoropropene.

[0005] The catalyst provided by this invention uses γ-alumina as a support and loads copper, nickel, and palladium. Based on the mass of the support (100%), the loading of copper is 5%–22%, the loading of nickel is 2%–10%, and the loading of palladium is 1%–5%. The preparation method of the catalyst includes the following steps:

[0006] Step 1: Treat γ-alumina with an aqueous nitric acid solution to obtain acid-treated γ-alumina;

[0007] Step 2: Dissolve the soluble salt of the metal element fully in pure water to obtain the impregnation solution;

[0008] Step 3: Add the acid-treated γ-alumina from Step 1 to the impregnation solution from Step 2 to ensure thorough impregnation;

[0009] Step 4: Dry the γ-alumina obtained after impregnation in Step 3 and then calcine it;

[0010] Step 5: After the catalyst precursor obtained after calcination in step 4 is reduced in a hydrogen atmosphere, it is then fluorinated in a mixture of nitrogen and hydrogen fluoride.

[0011] Step 6: The powder obtained after fluorination in step 5 is shaped, crushed, and sieved to obtain the catalyst.

[0012] Furthermore, in the above catalyst, based on the mass of the support, the preferred loading of copper is 10% to 15%, the loading of nickel is 4% to 6%, and the loading of palladium is 1.5% to 3%.

[0013] Furthermore, in step 1 of the above catalyst preparation method, γ-alumina is placed in a nitric acid aqueous solution with a mass fraction of 5% to 15%, boiled for 2 to 4 hours, cooled and washed with pure water until pH=4 to 6, dried in an oven at 60 to 80°C for 8 to 12 hours, and then dried at 110 to 120°C for 2 to 3 hours to obtain acid-treated γ-alumina.

[0014] Furthermore, in step 2 of the above catalyst preparation method, a soluble salt of a metal element is added to pure water and stirred and dissolved at 30-50°C for 1-2 hours to obtain an impregnation solution; when the metal element is copper, its soluble salt is selected from one or more of copper sulfate, copper nitrate, and copper chloride; when the metal element is nickel, its soluble salt is selected from one or more of nickel nitrate, nickel chloride, and nickel acetate; when the metal element is palladium, its soluble salt is selected from one or more of palladium sulfate, palladium chloride, and palladium nitrate.

[0015] Furthermore, in step 3 of the above catalyst preparation method, the volume ratio of the acid-treated γ-alumina to the impregnation liquid is 1:1.5-2.

[0016] Furthermore, in step 4 of the above catalyst preparation method, the drying temperature is 80-120℃ and the time is 5-8h, and the calcination temperature is 300-600℃ and the time is 3-6h.

[0017] Furthermore, in step 5 of the above catalyst preparation method, the reduction temperature is 300-500℃, the time is 3-6h, and the hydrogen flow rate is 200-400 mL / min.

[0018] Furthermore, in step 5 of the catalyst preparation method, the volume ratio of nitrogen to hydrogen fluoride in the mixed gas is 4:1, and the fluorination treatment temperature is 200–500°C and the time is 3–6 h.

[0019] Furthermore, in step 6 of the above catalyst preparation method, the powder obtained after fluorination is pressed into tablets using a tablet press under a pressure of 10-30 MPa, and then crushed and sieved to a mesh size of 5-20 mesh.

[0020] This invention also provides the application of the above-mentioned catalyst in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene via the catalytic reaction of 1,1,2,3-tetrachloropropene. The specific method is as follows: the catalyst is loaded into a fixed-bed reactor, hydrogen fluoride is used as the carrier gas, and 1,1,2,3-tetrachloropropene is introduced. The molar ratio of hydrogen fluoride to 1,1,2,3-tetrachloropropene is 10–15:1, and the mass hourly space velocity (HHSV) of 1,1,2,3-tetrachloropropene is 1–4 h⁻¹. -1 2-Chloro-3,3,3-trifluoropropene is synthesized by reaction under conditions of temperature 150–270℃ and pressure 0.8–2MPa.

[0021] The beneficial effects of this invention are as follows:

[0022] This invention uses 1,1,2,3-tetrachloropropene as a raw material, and synthesizes 2-chloro-3,3,3-trifluoropropene by treating the catalyst with HF followed by fluorine-chlorine exchange. In the production process of 2-chloro-3,3,3-trifluoropropene, this copper, nickel, and palladium composite metal catalyst exhibits high conversion rate, selectivity, long-term stable operation, low cost, and low pollution, conforming to the principles of green chemistry. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the embodiments, but the scope of protection of the present invention is not limited to these embodiments.

[0024] Example 1

[0025] In this embodiment, the catalyst uses γ-alumina as a support and is loaded with the metal elements copper, nickel, and palladium. Based on γ-alumina mass of 100%, the loading of copper is 5%, the loading of nickel is 2%, and the loading of palladium is 1%. The catalyst preparation method includes the following steps:

[0026] Step 1: Place γ-alumina in a 10wt% nitric acid aqueous solution, boil for 3 hours, cool down and wash with pure water until pH=5±0.2, dry in an oven at 80℃ for 8 hours, and then dry at 120℃ for 2 hours to obtain acid-treated γ-alumina.

[0027] Step 2: Weigh out copper nitrate, nickel nitrate, and palladium nitrate according to the mass ratio Cu:Ni:Pd=5:2:1, add them to pure water, and stir until they are completely dissolved to obtain the impregnation solution;

[0028] Step 3: Add the acid-treated γ-alumina to the impregnation solution obtained in Step 2 and impregnate at 50°C for 12 hours;

[0029] Step 4: Dry the γ-alumina obtained after impregnation in step 3 at 100°C for 8 hours, and then calcine it at 450°C for 3 hours.

[0030] Step 5: The catalyst precursor obtained after calcination in step 4 is placed in a hydrogen atmosphere with a hydrogen flow rate of 300 mL / min and reduced at 400℃ for 3 h. Then, a mixture of nitrogen and hydrogen fluoride is introduced for fluorination treatment for 5 h.

[0031] Step 6: Press the powder obtained after fluorination in step 5 into a tablet using a tablet press at 15 MPa pressure, then crush and pass it through a 10-mesh sieve to obtain the catalyst.

[0032] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 88% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 98%. After continuous reaction for 2000h, the conversion rate of the raw material decreased by 5%, and the selectivity of the target product decreased by 5%.

[0033] Example 2

[0034] The catalyst in this embodiment uses γ-alumina as a support and is loaded with the metal elements copper, nickel and palladium. Based on the mass of γ-alumina as 100%, the loading of copper is 8%, the loading of nickel is 3%, and the loading of palladium is 1.5%. The preparation method of the catalyst is the same as that in Example 1.

[0035] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹.-1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 90% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 99%. After continuous reaction for 2000h, the conversion rate of the raw material decreased by 4%, and the selectivity of the target product decreased by 6%.

[0036] Example 3

[0037] The catalyst in this embodiment uses γ-alumina as a support and is loaded with the metal elements copper, nickel and palladium. Based on the mass of γ-alumina as 100%, the loading of copper is 11%, the loading of nickel is 4%, and the loading of palladium is 2%. The preparation method of the catalyst is the same as that in Example 1.

[0038] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 100% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 99.5%. After continuous reaction for 2000h, the conversion rate of the raw material decreased by 2%, and the selectivity of the target product decreased by 3%.

[0039] Example 4

[0040] The catalyst in this embodiment uses γ-alumina as a support and is loaded with the metal elements copper, nickel and palladium. Based on the mass of γ-alumina as 100%, the loading of copper is 13%, the loading of nickel is 5%, and the loading of palladium is 2.5%. The preparation method of the catalyst is the same as that in Example 1.

[0041] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 97% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 97%. After continuous reaction for 2000h, the conversion rate of the raw material decreased by 4%, and the selectivity of the target product decreased by 5%.

[0042] Example 5

[0043] The catalyst in this embodiment uses γ-alumina as a support and is loaded with the metal elements copper, nickel and palladium. Based on the mass of γ-alumina as 100%, the loading of copper is 15%, the loading of nickel is 6% and the loading of palladium is 3%. The preparation method of the catalyst is the same as that in Example 1.

[0044] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 95% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 98%. After continuous reaction for 2000h, the conversion rate of the raw material decreased by 6%, and the selectivity of the target product decreased by 7%.

[0045] Example 6

[0046] The catalyst in this embodiment uses γ-alumina as a support and is loaded with the metal elements copper, nickel and palladium. Based on the mass of γ-alumina as 100%, the loading of copper is 17%, the loading of nickel is 7%, and the loading of palladium is 3.5%. The preparation method of the catalyst is the same as that in Example 1.

[0047] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 88% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 98%. After continuous reaction for 2000h, the conversion rate of the raw material decreased by 6%, and the selectivity of the target product decreased by 8%.

[0048] Example 7

[0049] The catalyst in this embodiment uses γ-alumina as a support and is loaded with the metal elements copper, nickel and palladium. Based on the mass of γ-alumina as 100%, the loading of copper is 19%, the loading of nickel is 8%, and the loading of palladium is 4%. The preparation method of the catalyst is the same as that in Example 1.

[0050] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 80% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 97%. After continuous reaction for 2000h, the conversion rate of the raw material decreased by 7%, and the selectivity of the target product decreased by 9%.

[0051] Example 8

[0052] The catalyst in this embodiment uses γ-alumina as a support and is loaded with the metal elements copper, nickel and palladium. Based on the mass of γ-alumina as 100%, the loading of copper is 22%, the loading of nickel is 10%, and the loading of palladium is 5%. The preparation method of the catalyst is the same as in Example 1.

[0053] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 75% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 97%. After continuous reaction for 2000h, the conversion rate of the raw material decreased by 7%, and the selectivity of the target product decreased by 10%.

[0054] Comparative Example 1

[0055] The catalyst in this comparative example uses γ-alumina as a support and is loaded with the metal elements copper and nickel. Based on the mass of γ-alumina as 100%, the loading of copper is 11% and the loading of nickel is 4%. The catalyst preparation method does not add palladium nitrate, and other steps are the same as in Example 1.

[0056] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 80% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 75%. After 1000 hours of continuous reaction, the conversion rate of the raw material decreased by 12%, and the selectivity of the target product decreased by 10%.

[0057] Comparative Example 2

[0058] The catalyst in this comparative example uses γ-alumina as a support and is loaded with the metal elements copper and nickel. Based on the mass of γ-alumina as 100%, the loading of copper is 11% and the loading of nickel is 4%. The catalyst preparation method does not add palladium nitrate and replaces copper sulfate with copper carbonate. Other steps are the same as in Example 1.

[0059] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 88% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 80%. After 1000 hours of continuous reaction, the conversion rate of the raw material decreased by 10%, and the selectivity of the target product decreased by 8%.

[0060] Comparative Example 3

[0061] The catalyst used in this comparative example is the same as that in Example 1.

[0062] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 20:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1 The reaction was carried out at a temperature of 280℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 86% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 82%. After 1000 hours of continuous reaction, the conversion rate of the raw material decreased by 8%, and the selectivity of the target product decreased by 6%.

[0063] Comparative Example 4

[0064] The catalyst in this comparative example uses γ-alumina as a support and is loaded with the metal elements copper, nickel, and palladium. Based on the mass of γ-alumina as 100%, the loading of copper is 13%, the loading of nickel is 5%, and the loading of palladium is 2.5%. The catalyst preparation method does not involve the introduction of a mixed gas of nitrogen and hydrogen fluoride for fluorination treatment. Other steps are the same as in Example 1.

[0065] The catalyst described above was loaded into a fixed-bed reactor, and the feedstock 1,1,2,3-tetrachloropropene and carrier gas HF were continuously introduced. The molar ratio of HF to 1,1,2,3-tetrachloropropene was 12:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1.5 h⁻¹. -1The reaction was carried out at a temperature of 250℃ and a pressure of 1.0MPa. Chromatographic analysis showed that the conversion rate of 1,1,2,3-tetrachloropropene reached 82% during the entire reaction process, and the selectivity of the target product 2-chloro-3,3,3-trifluoropropene reached 90%. After 1000 hours of continuous reaction, the conversion rate of the raw material decreased by 13%, and the selectivity of the target product decreased by 10%.

Claims

1. The application of a catalyst in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene from 1,1,2,3-tetrachloropropene, characterized in that: The catalyst was loaded into a fixed-bed reactor, and 1,1,2,3-tetrachloropropene was introduced using hydrogen fluoride as the carrier gas. The molar ratio of hydrogen fluoride to 1,1,2,3-tetrachloropropene was 10–15:1, and the mass hourly space velocity (WHSV) of 1,1,2,3-tetrachloropropene was 1–4 h⁻¹. -1 2-Chloro-3,3,3-trifluoropropene was synthesized by reaction under conditions of temperature 150–270℃ and pressure 0.8–2MPa. The catalyst uses γ-alumina as a support and is loaded with the metal elements copper, nickel, and palladium; based on the mass of the support (100%), the loading of copper is 10%–15%, the loading of nickel is 4%–6%, and the loading of palladium is 1.5%–3%. The method for preparing the catalyst includes the following steps: Step 1: Treat γ-alumina with an aqueous nitric acid solution to obtain acid-treated γ-alumina; Step 2: Dissolve the soluble salt of the metal element fully in pure water to obtain the impregnation solution; Step 3: Add the acid-treated γ-alumina from Step 1 to the impregnation solution from Step 2 to ensure thorough impregnation; Step 4: Dry the γ-alumina obtained after impregnation in Step 3 and then calcine it; Step 5: After the catalyst precursor obtained after calcination in step 4 is reduced in a hydrogen atmosphere, it is then fluorinated in a mixture of nitrogen and hydrogen fluoride. Step 6: The powder obtained after fluorination in step 5 is shaped, crushed, and sieved to obtain the catalyst.

2. The application of the catalyst according to claim 1 in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene by catalysis of 1,1,2,3-tetrachloropropene, characterized in that: In step 1, γ-alumina is placed in a nitric acid aqueous solution with a mass fraction of 5% to 15%, boiled for 2 to 4 hours, cooled and washed with pure water until pH=4 to 6, dried in an oven at 60 to 80°C for 8 to 12 hours, and then dried at 110 to 120°C for 2 to 3 hours to obtain acid-treated γ-alumina.

3. The application of the catalyst according to claim 1 in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene by catalysis of 1,1,2,3-tetrachloropropene, characterized in that: In step 2, a soluble salt of the metal element is added to pure water and stirred at 30-50°C for 1-2 hours to obtain an impregnation solution. When the metal element is copper, its soluble salt is selected from one or more of copper sulfate, copper nitrate, and copper chloride. When the metal element is nickel, its soluble salt is selected from one or more of nickel nitrate, nickel chloride, and nickel acetate. When the metal element is palladium, its soluble salt is selected from one or more of palladium sulfate, palladium chloride, and palladium nitrate.

4. The application of the catalyst according to claim 1 in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene by catalysis of 1,1,2,3-tetrachloropropene, characterized in that: In step 3, the volume ratio of the acid-treated γ-alumina to the impregnation solution is 1:1.5 to 2.

5. The application of the catalyst according to claim 1 in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene by catalysis of 1,1,2,3-tetrachloropropene, characterized in that: In step 4, the drying temperature is 80-120℃ and the time is 5-8 hours, and the calcination temperature is 300-600℃ and the time is 3-6 hours.

6. The application of the catalyst according to claim 1 in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene by catalysis of 1,1,2,3-tetrachloropropene, characterized in that: In step 5, the reduction temperature is 300–500℃, the time is 3–6 h, and the hydrogen flow rate is 200–400 mL / min.

7. The application of the catalyst according to claim 1 in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene by catalysis of 1,1,2,3-tetrachloropropene, characterized in that: In step 5, the volume ratio of nitrogen to hydrogen fluoride in the mixed gas is 4:1, and the fluorination treatment temperature is 200-500℃ and the time is 3-6h.

8. The application of the catalyst according to claim 1 in the continuous synthesis of 2-chloro-3,3,3-trifluoropropene by catalysis of 1,1,2,3-tetrachloropropene, characterized in that: In step 6, the powder obtained after fluorination is compressed into tablets using a tablet press at a pressure of 10-30 MPa, and then crushed and sieved with a mesh size of 5-20 mesh.