Catalyst for continuously producing 3-chloro-1, 1, 1, 3-tetrafluoropropane through gas-solid phase reaction as well as preparation method and application of catalyst

Abstract

The invention discloses a catalyst for gas-solid phase continuous production of 3-chloro-1, 1, 1, 3-tetrafluoropropane as well as a preparation method and application of the catalyst. The catalyst comprises a copper and nitrogen co-modified carbon material, and the copper and nitrogen co-modified carbon material comprises a carbon material serving as a carrier, copper loaded on the carrier and serving as an active component, and a nitrogen-containing functional group formed on the surface of the copper or / and the carbon material. The preparation method comprises the following step: co-modifying a carbon material by using a copper salt and a nitrogen-containing substance to obtain the catalyst for continuously producing 3-chloro-1, 1, 1, 3-tetrafluoropropane through a gas-solid phase reaction. The invention further provides a method for continuously producing the 3-chloro-1, 1, 1, 3-tetrafluoropropane through the gas-solid phase reaction. According to the catalyst provided by the invention, an active component copper and an auxiliary component nitrogen-containing functional group are integrated on a carbon material carrier, so that gas-solid phase continuous production of 3-chloro-1, 1, 1, 3-tetrafluoropropane is realized, the problems of difficulty in catalyst separation, limited productivity and the like in a traditional intermittent kettle reaction are solved, and the production efficiency is improved. Meanwhile, the catalyst is low in synthesis cost, mild in process reaction condition and suitable for industrial amplification.

Description

Technical Field

[0001] The present invention relates to the field of gas-solid reaction catalysts, and specifically relates to a catalyst for continuously producing 3-chloro-1,1,1,3-tetrafluoropropane by gas-solid reaction, a preparation method and an application, belonging to the field of chemical engineering technology. Background Art

[0002] 3-chloro-1,1,1,3-tetrafluoropropane (HCFC-244fa) is an important fine chemical intermediate. Patents CN111454121A and CN113527041A disclose the preparation of 1,3,3,3-tetrafluoropropene (HFO-1234ze) by one-step dehydrochlorination of HCFC-244fa. Among them, trans-HFO-1234ze (E) is a potential refrigerant for high-temperature heat pumps, has good compatibility with most plastics, and can be used as a substitute for difluoromethane (HFC-32) and 1,1,1,2-tetrafluoroethane (HFC-134a). It has a low global warming potential (GWP), an ozone depletion potential (ODP) of 0, and low toxicity.

[0003] Patents CN101575263A and US20150259267 A1 disclose the one-step dehydrofluorination of HCFC-244fa to produce 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd). Trans-HCFO-1233zd (E) is a non-flammable and low-GWP refrigerant, which can replace 2,2-dichloro-1,1,1-trifluoroethane (R-123) in low-pressure centrifugal chillers and is an environmentally friendly substitute in applications such as organic Rankine cycles and high-temperature heat pumps.

[0004] With the large-scale application of HFO-1234ze and HCFO-1233zd, it is of great value to develop a highly efficient and high-capacity process route for synthesizing HCFC-244fa.

[0005] Patents CN1266045A and US20130211156A1 respectively disclose processes for preparing HCFC-244fa by partial fluorochlorination exchange reaction of 1,1,1,3,3-pentachloropropane or 1,1,1,3-tetrachloro-3-fluoropropane with HF. However, this method involves a fluorochlorination exchange reaction, and its degree is usually difficult to control, resulting in many by-products.

[0006] CN101560138A discloses the one-step synthesis of HCFC-244fa by telomerization reaction of vinyl fluoride and chlorotrifluoromethane at 120 °C in a batch reactor using a mixture of boron trifluoride, aluminum trichloride and iron trichloride as a catalyst. This method has high product selectivity, but the reaction needs to be carried out in a batch reactor, so this process has problems such as difficult catalyst separation, limited single-reactor production capacity, and low production efficiency.

[0007] Patent CN111875473A discloses that a nickel-rhodium-zinc composite catalyst is used to carry out a telomerization reaction of vinyl fluoride and chlorotrifluoromethane at 350 °C in a tubular reactor to produce HCFC-244fa. Although this process realizes the continuous production of HCFC-244fa, the synthesis cost of this catalyst is high, the reaction process temperature is high, and the energy consumption is large, which is not suitable for industrial scale-up. Summary of the Invention

[0008] In order to solve the above technical problems, the present invention provides a catalyst for the continuous gas-solid phase reaction to produce 3-chloro-1,1,1,3-tetrafluoropropane, its preparation method and application.

[0009] To achieve the foregoing invention object, the technical solutions adopted by the present invention include:

[0010] The present invention first provides a catalyst for the continuous gas-solid phase reaction to produce 3-chloro-1,1,1,3-tetrafluoropropane, the catalyst comprising a copper and nitrogen co-modified carbon material, the copper and nitrogen co-modified carbon material comprising a carbon material as a carrier, copper as an active component supported on the carrier, and nitrogen-containing functional groups formed on the surface of the carbon material and / or copper;

[0011] Preferably, the content of copper in the catalyst is 0.1-20 wt%, and the content of nitrogen is 0.1-20 wt%; more preferably, the content of copper in the catalyst is 0.2-10 wt%, and the content of nitrogen is 0.2-10 wt%.

[0012] Preferably, the carbon material as the carrier in the present invention is selected from carbon materials in which carbon atoms in the structure adopt sp 2 hybridization; more preferably, selected from at least one of activated carbon, carbon nanotubes, graphene, and carbon nitride; the telomerization reaction catalyzed by copper involves a free radical mechanism, and the delocalized π electron system is conducive to the formation and stabilization of free radicals.

[0013] The present invention also provides a preparation method of the catalyst for the continuous gas-solid phase reaction to produce 3-chloro-1,1,1,3-tetrafluoropropane, which comprises: co-modifying a carbon material with a copper salt solution and a nitrogen-containing substance to obtain a catalyst for the continuous gas-solid phase reaction to produce 3-chloro-1,1,1,3-tetrafluoropropane.

[0014] Preferably, the copper salt in the present invention is selected from copper ion salts containing monovalent or divalent copper ions; more preferably, it is selected from at least one of cuprous chloride, copper chloride, copper nitrate, and copper sulfate; even more preferably, the anion in the ionic salt includes chloride ions. The catalytic active center of the catalyst telomerization system is monovalent copper, and chloride ions can stabilize monovalent copper. The nitrogen-containing substance in the present invention includes inorganic nitrogen and organic nitrogen; preferably, the nitrogen-containing substance includes at least one of ammonia, acetonitrile, triethylamine, tert-butylamine, n-butylamine, and pyridine.

[0015] Preferably, the mass ratio of the carbon material to the copper salt in the present invention is 1000:1 to 5:1; more preferably, the mass ratio is 500:1 to 10:1.

[0016] Preferably, the mass ratio of carbon element in the carbon material to nitrogen element in the nitrogen-containing substance in the present invention is 500:1 to 1:1; more preferably, the mass ratio is 100:1 to 5:1.

[0017] Preferably, the solvent of the copper salt solution is hydrochloric acid or deionized water, and the concentration of copper element in the copper salt solution is 0.01 mol / L to 20 mol / L; more preferably, the concentration is 0.1 mol / L to 10 mol / L.

[0018] In some preparation examples, the preparation method specifically includes:

[0019] Heating a first mixture containing a carbon material and a copper salt solution, and raising the temperature to 100 - 800 °C for roasting to obtain a copper-modified carbon material; even more preferably, roasting is carried out at 200 - 600 °C;

[0020] And heating a second mixture containing the copper-modified carbon material and the nitrogen-containing substance, raising the temperature to 100 - 800 °C for roasting to obtain the catalyst for continuously producing 3-chloro-1,1,1,3-tetrafluoropropane by gas-solid phase reaction. Even more preferably, roasting is carried out at 200 - 600 °C.

[0021] In some other preparation examples, the preparation method specifically includes:

[0022] Heating a third mixture of a carbon material and a nitrogen-containing substance, raising the temperature to 100 - 1000 °C for roasting to obtain a nitrogen-modified carbon material; even more preferably, roasting is carried out at 200 - 900 °C;

[0023] And heating a fourth mixture of the nitrogen-modified carbon material and the copper salt solution, and raising the temperature to 100 - 800 °C for roasting to obtain a copper and nitrogen co-modified carbon material; even more preferably, roasting is carried out at 200 - 600 °C.

[0024] Calcination of copper salts and carbon materials at medium temperatures (200 - 600 °C) will form more cuprous copper, while high temperatures will form inactive zero-valent copper. Therefore, the calcination temperature is preferably medium temperature.

[0025] An embodiment of the present invention also provides an application of the catalyst for continuously producing 3-chloro-1,1,1,3-tetrafluoropropane in the gas-solid phase reaction in the continuous production of 3-chloro-1,1,1,3-tetrafluoropropane in the gas-solid phase reaction.

[0026] Correspondingly, an embodiment of the present invention also provides a method for continuously producing 3-chloro-1,1,1,3-tetrafluoropropane in the gas-solid phase reaction, which includes:

[0027] Encapsulate the catalyst for continuously producing 3-chloro-1,1,1,3-tetrafluoropropane in the gas-solid phase reaction in a gas-solid phase fixed bed reaction device to form a catalyst bed layer;

[0028] Continuously introduce the reaction raw material gas of vinyl fluoride and chlorotrifluoromethane into the catalyst bed layer at a ratio of 2:1 - 1:2, increase the inlet pressure of the reaction raw material gas to 0.1 - 2.0 MPa, heat the temperature of the catalyst bed layer to 80 - 300 °C, and obtain 3-chloro-1,1,1,3-tetrafluoropropane through catalytic telomerization reaction; preferably, the reaction raw material ratio of vinyl fluoride and chlorotrifluoromethane is 1:1.5 - 1.5:1, the inlet pressure of the reaction raw material gas is increased to 0.1 - 1.0 MPa, and the temperature of the catalyst bed layer is 100 - 200 °C; more preferably, the reaction raw material ratio of vinyl fluoride and chlorotrifluoromethane is 1:1.2 - 1.2:1, the inlet pressure of the reaction raw material gas is increased to 0.3 - 0.7 MPa, and the temperature of the catalyst bed layer is 120 - 180 °C.

[0029] This study found that appropriately increasing the reaction pressure or temperature is beneficial to improving the conversion rate of the product. However, if the reaction pressure or temperature is too high, it is easy to produce by-products of the polymerization of chlorotrifluoromethane and multiple vinyl fluorides; Detailed implementation

[0030] The following will further illustrate the present invention in combination with specific preparation examples and examples, but the present invention is not limited to these specific implementation manners. Those skilled in the art should recognize that the present invention covers all alternative solutions, improvement solutions, and equivalent solutions that may be included within the scope of the claims.

[0031] I. Catalyst preparation

[0032] Preparation Example 1

[0033] Take 5.0 g of cuprous chloride and dissolve it in 15.0 mL of concentrated hydrochloric acid. Then impregnate the above solution into 45.0 g of activated carbon (20 - 40 mesh, BET area 1000 m 2 / g), and dried overnight in an oven at 100 °C. The dried catalyst precursor was placed in a tube furnace, nitrogen was introduced, and it was heated to 300 °C at a heating rate of 5 °C / min and calcined for 3 hours. After cooling to room temperature, a copper-modified carbon material was obtained. Subsequently, in the tube furnace, the copper-modified carbon material was heated to 300 °C at a heating rate of 5 °C / min in an ammonia atmosphere of 25 mL / min and calcined for 3 hours. After cooling to room temperature, a copper- and nitrogen-codoped carbon material was obtained. The nitrogen content in the copper- and nitrogen-codoped carbon material was measured to be 1.3 wt% by elemental analysis, and the copper content was measured to be 6.5 wt% by atomic absorption spectrometry.

[0034] Preparation Example 2

[0035] The method of this preparation example is the same as that of Preparation Example 1, except that: for the preparation of the copper-modified carbon material, 8.6 g of copper chloride dihydrate was dissolved in 20.0 mL of deionized water, and then the above solution was impregnated on activated carbon. The nitrogen content in the copper- and nitrogen-codoped carbon material was 1.4 wt%, and the copper content was 6.5 wt%.

[0036] Preparation Example 3

[0037] The method of this preparation example is the same as that of Preparation Example 1, except that: for the preparation of the copper-modified carbon material, 14.3 g of copper nitrate hexahydrate was dissolved in 20.0 mL of deionized water, and then the above solution was impregnated on activated carbon. The nitrogen content in the copper- and nitrogen-codoped carbon material was 1.8 wt%, and the copper content was 6.5 wt%.

[0038] Preparation Example 4

[0039] The method of this preparation example is the same as that of Preparation Example 1, except that: for the preparation of the copper-modified carbon material, 12.6 g of copper sulfate pentahydrate was dissolved in 200 mL of deionized water, and then the above solution was impregnated on activated carbon. The nitrogen content in the copper- and nitrogen-codoped carbon material was 1.2 wt%, and the copper content was 6.4 wt%.

[0040] Preparation Example 5

[0041] The method of this preparation example is the same as that of Preparation Example 1, except that: for the preparation of the copper-modified carbon material, 1.1 g of cuprous chloride was dissolved in 3.3 mL of concentrated hydrochloric acid. Then the above solution was impregnated onto 10.0 g of multi-walled carbon nanotubes. The nitrogen content in the copper- and nitrogen-codoped carbon material was 1.5 wt%, and the copper content was 6.5 wt%.

[0042] Preparation Example 6

[0043] The method of this preparation example is the same as that of Preparation Example 1, except that: for the preparation of the copper-modified carbon material, 1.1 g of cuprous chloride was taken and dissolved in 3.3 mL of concentrated hydrochloric acid. Then the above solution was impregnated onto 10.0 g of graphene. The nitrogen content in the copper and nitrogen co-modified carbon material is 1.6 wt%, and the copper content is 6.5 wt%.

[0044] Preparation Example 7

[0045] The method of this preparation example is the same as that of Preparation Example 1, except that: for the preparation of the copper-modified carbon material, 1.1 g of cuprous chloride was taken and dissolved in 3 mL of concentrated hydrochloric acid. Then the above solution was impregnated onto 10.0 g of carbon nitride. The nitrogen content in the copper and nitrogen co-modified carbon material is 55.1 wt%, and the copper content is 6.5 wt%.

[0046] Preparation Example 8

[0047] The method of this preparation example is the same as that of Preparation Example 1, except that: in the preparation of the copper-modified carbon material, the calcination temperature in a nitrogen atmosphere is 600 °C. The nitrogen content in the copper and nitrogen co-modified carbon material is 1.1 wt%, and the copper content is 6.5 wt%.

[0048] Preparation Example 9

[0049] The method of this preparation example is the same as that of Preparation Example 1, except that: for the copper-modified carbon material, the calcination temperature in an ammonia atmosphere is 600 °C. The nitrogen content in the copper and nitrogen co-modified carbon material is 4.1 wt%, and the copper content is 6.3 wt%.

[0050] Preparation Example 10

[0051] The method of this preparation example is the same as that of Preparation Example 10, except that: for the copper-modified carbon material, 20 mL of acetonitrile was added for impregnation and dried in an oven at 60 °C for 2 hours. Subsequently, in a tubular furnace, the impregnated copper-modified carbon material was heated to 300 °C at a heating rate of 5 °C / min in a nitrogen atmosphere of 25 mL / min and calcined for 3 hours. After cooling to room temperature, the copper and nitrogen co-modified carbon material was obtained. The nitrogen content in the copper and nitrogen co-modified carbon material is 1.0 wt%, and the copper content is 6.4 wt%.

[0052] Preparation Example 11

[0053] The method of this preparation example is the same as that of Preparation Example 10, except that: for the copper-modified carbon material, 20 mL of triethylamine was added for impregnation. The nitrogen content in the copper and nitrogen co-modified carbon material is 0.9 wt%, and the copper content is 6.5 wt%.

[0054] Preparation Example 12

[0055] The method of this preparation example is the same as that of Preparation Example 10, except that: for the copper-modified carbon material, 20 mL of tert-butylamine was added for impregnation. The nitrogen content in the copper and nitrogen co-modified carbon material is 0.8 wt%, and the copper content is 6.5 wt%.

[0056] Preparation Example 13

[0057] The method of this preparation example is the same as that of Preparation Example 10, except that: for the copper-modified carbon material, 20 mL of n-butylamine was added for impregnation. The nitrogen content in the copper and nitrogen co-modified carbon material is 0.8 wt%, and the copper content is 6.4 wt%.

[0058] Preparation Example 14

[0059] The method of this preparation example is the same as that of Preparation Example 10, except that: for the copper-modified carbon material, 20 mL of pyridine was added for impregnation. The nitrogen content in the copper and nitrogen co-modified carbon material is 0.7 wt%, and the copper content is 6.4 wt%.

[0060] Preparation Example 15

[0061] Take 45.0 g of activated carbon (20 - 40 mesh, BET surface area 1000 m 2 / g) and place it in a tubular furnace. Heat it to 300 °C at a heating rate of 5 °C / min in an ammonia atmosphere of 25 mL / min and calcine for 3 hours. Cool down to room temperature to obtain the nitrogen-modified carbon material. Take 5.0 g of cuprous chloride and dissolve it in 15 mL of concentrated hydrochloric acid. Impregnate the hydrochloric acid solution of cuprous chloride into the above nitrogen-modified carbon material and dry it overnight in an oven at 100 °C. In the tubular furnace, heat the copper-impregnated nitrogen-modified carbon material to 300 °C at a heating rate of 5 °C / min and calcine for 3 hours. After cooling down to room temperature, a copper and nitrogen co-modified carbon material is obtained. The nitrogen content of the sample is measured to be 0.4 wt% by elemental analysis, and the copper content is measured to be 6.5 wt% by atomic absorption spectrometry.

[0062] Preparation Example 16

[0063] The method of this preparation example is the same as that of Preparation Example 15, except that: in the preparation of the nitrogen-modified carbon material, the calcination temperature in the ammonia atmosphere is 600 °C. The nitrogen content in the copper and nitrogen co-modified carbon material is 2.7 wt%, and the copper content is 6.5 wt%.

[0064] Preparation Example 17

[0065] The method of this preparation example is the same as that of Preparation Example 15, except that: in the preparation of the nitrogen-modified carbon material, take 20 mL of n-butylamine and impregnate it in 45.0 g of activated carbon (20 - 40 mesh, BET surface area 1000 m 2 / g), and then dried in an oven at 60 °C for 2 hours. In a tubular furnace, the impregnated copper-modified carbon material was heated to 300 °C at a heating rate of 5 °C / min in a nitrogen atmosphere of 25 mL / min and calcined for 3 hours. The nitrogen content in the copper and nitrogen co-modified carbon material was 0.2 wt%, and the copper content was 6.3 wt%.

[0066] Preparation Example 18

[0067] The method of this preparation example is the same as that of Preparation Example 17, except that: in the preparation of the nitrogen-modified carbon material, it was calcined at 600 °C. The nitrogen content in the copper and nitrogen co-modified carbon material was 1.2 wt%, and the copper content was 6.4 wt%.

[0068] II. Catalyst Application

[0069] Example 1

[0070] In this example, the reaction tube of the gas-solid fixed-bed reactor was an electrically heated tubular reactor with an inner diameter of 19 mm and a length of 0.5 m. The reaction process was as follows:

[0071] 10 g of the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 1 was loaded into the reaction tube. Chlorotrifluoromethane and vinyl fluoride were continuously fed into the reaction tube simultaneously. The volume ratio of chlorotrifluoromethane to vinyl fluoride was 1:1, and the total flow rate was 50 mL / min. The reaction pressure was adjusted to 0.1 MPa by adjusting the back pressure valve. The catalyst bed temperature was heated to 100 °C for reaction. The crude product of 3-chloro-1,1,1,3-tetrafluoropropane was collected at the end of the fixed bed, and the obtained product was analyzed by gas chromatography. The conversion rate of vinyl fluoride was 71%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane was 70%. The remaining products were chlorotrifluoromethane and by-products of polymerization of two or more vinyl fluorides.

[0072] Example 2

[0073] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 2 was used. The conversion rate of vinyl fluoride was 68%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane was 67%.

[0074] Example 3

[0075] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 3 was used. The conversion rate of vinyl fluoride was 52%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane was 65%.

[0076] Example 4

[0077] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 4 is used. The conversion rate of vinyl fluoride is 23%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 67%.

[0078] Example 5

[0079] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 5 is used. The conversion rate of vinyl fluoride is 86%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 79%.

[0080] Example 6

[0081] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 6 is used. The conversion rate of vinyl fluoride is 77%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 74%.

[0082] Example 7

[0083] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 7 is used. The conversion rate of vinyl fluoride is 83%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 71%.

[0084] Example 8

[0085] The method of this example is the same as that of Example 1, except that: activated carbon without copper-nitrogen modification is used as the catalyst. The conversion rate of vinyl fluoride is 11%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 24%.

[0086] Example 9

[0087] The method of this example is the same as that of Example 1, except that: no catalyst is installed in the reaction tube. The conversion rate of vinyl fluoride is 0%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 0%.

[0088] Example 10

[0089] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 8 is used. The conversion rate of vinyl fluoride is 33%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 59%.

[0090] Example 11

[0091] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 9 is used. The conversion rate of vinyl fluoride is 45%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 63%.

[0092] Example 12

[0093] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 10 is used. The conversion rate of vinyl fluoride is 70%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 75%.

[0094] Example 13

[0095] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 11 is used. The conversion rate of vinyl fluoride is 75%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 83%.

[0096] Example 14

[0097] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 12 is used. The conversion rate of vinyl fluoride is 75%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 79%.

[0098] Example 15

[0099] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 13 is used. The conversion rate of vinyl fluoride is 74%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 97%.

[0100] Example 16

[0101] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 14 is used. The conversion rate of vinyl fluoride is 71%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 85%.

[0102] Example 17

[0103] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 15 is used. The conversion rate of vinyl fluoride is 52%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 70%.

[0104] Example 18

[0105] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 16 is used. The conversion rate of vinyl fluoride is 60%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 68%.

[0106] Example 19

[0107] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 17 is used. The conversion rate of vinyl fluoride is 21%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 84%.

[0108] Example 20

[0109] The method of this example is the same as that of Example 1, except that: the copper-nitrogen co-modified carbon catalyst prepared in Preparation Example 18 is used. The conversion rate of vinyl fluoride is 53%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 65%.

[0110] Example 21

[0111] The method of this example is the same as that of Example 1, except that: the back pressure valve is adjusted to adjust the reaction pressure to 0.6 MPa. Gas chromatography analysis shows that the conversion rate of vinyl fluoride is 92%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 98%.

[0112] Example 22

[0113] The method of this example is the same as that of Example 1, except that: the back pressure valve is adjusted to adjust the reaction pressure to 1.0 MPa. Gas chromatography analysis shows that the conversion rate of vinyl fluoride is 99%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 79%.

[0114] Example 23

[0115] The method of this example is the same as that of Example 21, except that: the temperature of the catalyst bed layer is heated to 150 °C for the reaction. Gas chromatography analysis shows that the conversion rate of vinyl fluoride is 99%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 96%.

[0116] Example 24

[0117] The method of this example is the same as that of Example 21, except that: the temperature of the catalyst bed layer is heated to 200 °C for the reaction. Gas chromatography analysis shows that the conversion rate of vinyl fluoride is 99%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 71%.

[0118] Example 25

[0119] The method of this example is the same as that of Example 23, except that: the volume ratio of chlorotrifluoromethane to vinyl fluoride is 1:1.5. Gas chromatography analysis shows that the conversion rate of vinyl fluoride is 99%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 91%.

[0120] Example 26

[0121] The method of this example is the same as that of Example 23, except that: the volume ratio of chlorotrifluoromethane to vinyl fluoride is 1.5:1. Gas chromatography analysis shows that the conversion rate of vinyl fluoride is 95%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 85%.

[0122] Example 27

[0123] The method of this example is the same as that of Example 23, except that: activated carbon without copper-nitrogen modification is used as the catalyst. Gas chromatography analysis shows that the conversion rate of vinyl fluoride is 18%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 36%.

[0124] Example 28

[0125] The method of this example is the same as that of Example 23, except that: no catalyst is loaded in the reaction tube. Gas chromatography analysis shows that the conversion rate of vinyl fluoride is 0%, and the selectivity of 3-chloro-1,1,1,3-tetrafluoropropane is 0%.

[0126] The data sorting results of each example are shown in Tables 1 to 3 below.

[0127] Table 1 Effects of copper metal salt precursors and carbon carriers on the conversion rate and selectivity of the telomerization reaction of chlorotrifluoromethane and vinyl fluoride catalyzed by the co-modified catalyst a

[0128]

[0129] a The reaction is carried out at 100 °C, the volume ratio of chlorotrifluoromethane to vinyl fluoride is 1:1, and the reaction pressure is 0.1 MPa. Catalyst preparation: After the metal copper salt is impregnated on the carbon carrier, it is calcined with nitrogen at 300 °C to obtain copper-modified carbon material, and then the copper-modified carbon material is treated with ammonia at 300 °C to obtain copper and nitrogen co-modified carbon material.

[0130] Table 2 Effects of the calcination temperature and sequence of the copper modification and nitrogen modification steps, and the nitrogen-containing reagent for nitrogen modification on the conversion rate and selectivity of the telomerization reaction of chlorotrifluoromethane and vinyl fluoride catalyzed by the co-modified catalyst a

[0131]

[0132]

[0133] aThe reaction is carried out at 100 °C, the volume ratio of chlorotrifluoromethane to vinyl fluoride is 1:1, and the reaction pressure is 0.1 MPa. Catalyst preparation: A concentrated hydrochloric acid solution of CuCl is impregnated on activated carbon and then calcined in nitrogen to obtain a copper-modified carbon material. Different nitrogen-containing reagents are added to the copper-modified carbon material and calcined to prepare a copper and nitrogen co-modified carbon material. b Catalyst preparation: First, the activated carbon is nitrogen-modified, and then the nitrogen-modified carbon material is copper-modified to obtain a copper and nitrogen co-modified carbon material.

[0134] Table 3 Effects of reaction temperature, pressure, and raw material ratio on the conversion rate and selectivity of the telomerization reaction of chlorotrifluoromethane and vinyl fluoride a

[0135]

[0136]

[0137] a The telomerization reaction of chlorotrifluoromethane and vinyl fluoride catalyzed by a copper and nitrogen co-modified catalyst. Catalyst preparation: A concentrated hydrochloric acid solution of CuCl is impregnated on activated carbon and then calcined in nitrogen at 300 °C to obtain a copper-modified carbon material. The copper-modified carbon material is mixed with n-butylamine and then treated at 300 °C to obtain a copper and nitrogen co-modified carbon material. b The conversion rate is calculated based on vinyl fluoride.

[0138] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the present invention. For those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention.

Claims

1. A catalyst for the continuous production of 3-chloro-1,1,1,3-tetrafluoropropane by gas-solid phase reaction, characterized in that, It includes a copper and nitrogen co-modified carbon material, and the copper and nitrogen co-modified carbon material includes a carbon material as a carrier, copper as an active component loaded on the carbon carrier, and nitrogen-containing functional groups formed on the surface of the copper active component and / or the surface of the carbon material.

2. The catalyst for continuously producing 3-chloro-1,1,1,3-tetrafluoropropane by gas-solid phase reaction according to claim 1, characterized in that: The content of copper in the catalyst is 0.1-20 wt%, and the content of nitrogen is 0.1-20 wt%.

3. The catalyst for the continuous production of 3-chloro-1,1,1,3-tetrafluoropropane by gas-solid reaction according to claim 1, characterized in that: The carbon material used as the carrier is selected from carbon materials in which the carbon atoms in the structure adopt sp 2 hybridization.

4. A method for preparing the catalyst according to any one of claims 1-3, characterized in that, It includes: Co-modifying the carbon material with a copper salt and a nitrogen-containing substance to obtain the catalyst for the gas-solid phase continuous production of 3-chloro-1,1,1,3-tetrafluoropropane.

5. The preparation method according to claim 4, characterized in that, Specifically, it includes: Heating a first mixture containing a carbon material and a copper salt solution, raising the temperature to 100-800 °C for roasting to obtain a copper-modified carbon material; And heating a second mixture containing the copper-modified carbon material and a nitrogen-containing substance, raising the temperature to 100-800 °C for roasting to obtain the catalyst.

6. The preparation method according to claim 4, characterized in that, Specifically, it includes: Heating a third mixture containing a carbon material and a nitrogen-containing substance, raising the temperature to 100-1000 °C for roasting to obtain a nitrogen-modified carbon material; And heating a fourth mixture containing the nitrogen-modified carbon material and a copper salt solution, raising the temperature to 100-800 °C for roasting to obtain the catalyst.

7. The preparation method according to claim 5 or 6, characterized in that: The mass ratio of the carbon material to the copper salt is 1000:1-5:1; And / or, the mass ratio of carbon element in the carbon material to nitrogen element in the nitrogen-containing substance is 500:1-1:1; And / or, the copper salt is selected from copper ion salts containing monovalent or divalent; And / or, the solvent of the copper salt solution is hydrochloric acid or deionized water; And / or, the concentration of copper element in the copper salt solution is 0.01 mol / L-20 mol / L; And / or, the nitrogen-containing substance is inorganic nitrogen or organic nitrogen.

8. The preparation method according to claim 7, characterized in that: The nitrogen-containing substance is at least one of ammonia, acetonitrile, triethylamine, tert-butylamine, n-butylamine, pyridine.

9. Application of the catalyst for the gas-solid phase reaction continuous production of 3-chloro-1,1,1,3-tetrafluoropropane according to any one of claims 1-3 in the gas-solid phase reaction continuous production of 3-chloro-1,1,1,3-tetrafluoropropane.

10. A method for the continuous gas-solid reaction to produce 3-chloro-1,1,1,3-tetrafluoropropane, characterized in that It includes: Loading the catalyst for the gas-solid phase reaction continuous production of 3-chloro-1,1,1,3-tetrafluoropropane according to any one of claims 1-3 into a gas-solid phase fixed bed reaction device to form a catalyst bed layer; Continuously introducing the reaction raw material gas of chlorotrifluoromethane and vinyl fluoride into the catalyst bed layer at a molar ratio of 1:2-2:1, the pressure of the reaction raw material gas is 0.1-2.0 MPa, heating the temperature of the catalyst bed layer to 80-300 °C, and obtaining 3-chloro-1,1,1,3-tetrafluoropropane through a telomerization reaction.

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