Application of a Boron Nitride-Coated Metal Catalyst in the Selective Hydrogenation Reaction of Acetylene

Abstract

The present invention discloses an application of a boron nitride-coated metal catalyst in the catalytic selective hydrogenation reaction of acetylene. The boron nitride-coated metal catalyst (M@BN) is prepared by two-step heat treatment using sodium amide (NaNH2), sodium borohydride (NaBH4), and a metal salt as reaction raw materials under an inert atmosphere. It is loaded into an atmospheric fixed-bed reactor for use in the catalytic selective hydrogenation reaction of acetylene. In the M@BN catalyst of the present invention, the nano-porous structure of the outer-layer coated h-BN is well retained, enabling gas acetylene molecules to fully approach the M active metal centers exposed in the form of single atoms, which helps to improve the catalytic selectivity. At the same time, the existence in the form of M nanoparticles can provide more single-atom type active centers, which helps to improve the catalytic activity.

Description

Technical Field

[0001] The present invention belongs to the technical field of acetylene selective hydrogenation, and particularly relates to the application of a boron nitride-coated metal catalyst in the catalytic acetylene selective hydrogenation reaction. Background Art

[0002] Ethylene is an important platform compound in the chemical industry and is widely used in the production of synthetic fibers, synthetic rubbers, synthetic plastics, synthetic ethanol, etc. The output of ethylene is an important indicator to measure the national economy. At present, ethylene can be produced industrially by naphtha cracking or acetylene selective hydrogenation. The ethylene fraction produced by naphtha cracking contains 0.1 - 2.0 vol% of acetylene, which will not only poison the catalyst in the subsequent polyethylene production process, reduce the service life of the catalyst, and lead to a decline in the product quality of polyethylene, but also the presence of acetylene will form explosive oligomers, bringing certain safety hazards. Therefore, catalytic hydrogenation is the key measure for the petroleum industry to remove trace acetylene in ethylene. During the process of removing acetylene, attention should also be paid to preventing the over-hydrogenation of acetylene to produce ethane, otherwise the polymerization reaction will be terminated. For decades, how to effectively remove acetylene while avoiding side reactions such as further hydrogenation or oligomerization of ethylene has always been a problem worthy of exploration. Therefore, whether it is to remove trace acetylene in the feed gas (to ensure that the acetylene content is reduced to less than 1 ppm to meet the process requirements) or directly prepare ethylene from acetylene, selective hydrogenation is crucial.

[0003] Currently, the methods for converting acetylene to ethylene include catalytic hydrogenation method, porous material adsorption method, complexation adsorption method, ammoniation method, rectification method, copper acetylide precipitation method, solvent absorption method, etc. Among them, the selective catalytic hydrogenation method has a simple process. It catalytically hydrogenates acetylene in the ethylene-rich stream to ethylene, can increase the ethylene output while removing trace acetylene, avoid the loss of ethylene, has low energy consumption and is environmentally friendly, and is the most widely used method in industrial applications.

[0004] An ideal acetylene selective hydrogenation catalyst should not only have high selectivity for ethylene to avoid deep hydrogenation to produce ethane, but also avoid coupled hydrogenation to produce oligomers. In the acetylene selective hydrogenation system, compared with other hydrogenation metal catalysts, Pd-based noble metal catalysts have very excellent hydrogenation activity in the preparation of ethylene by acetylene selective hydrogenation and are the best reported acetylene selective hydrogenation catalysts so far. The excellent activity of Pd at low temperatures is due to the overall size effect of the active sites. On Pd, the saturation rate of one double bond of an alkyne or a diene and the subsequent hydrogenation of the product olefin usually have the same order of magnitude. Therefore, compared with the formed monoene, the adsorption of dienes or alkynes is stronger. The adsorption coefficient of alkynes or dienes is always higher, which results in their preferential hydrogenation in competitive hydrogenation, although as individual substrates, their hydrogenation rate is slower than that of olefins.

[0005] However, there are inevitable problems with Pd-based supported catalysts in the acetylene selective hydrogenation reaction, among which the over-hydrogenation of ethylene to ethane is the biggest challenge for Pd-based catalysts. [1] Since Pd-based catalysts have high activity, both acetylene and ethylene are strongly adsorbed on the surface of metallic Pd species. The low kinetic barrier for the hydrogenation of ethylene to ethane leads to the inevitable direct over-hydrogenation of acetylene to ethane. [2] This is accompanied by polymerization side reactions and carbon deposition. Severe coke formation may cause catalyst deactivation by blocking catalytic active sites. For high acetylene conversion rates, Pd-based catalysts show a decrease in selectivity for ethylene and exhibit a short lifespan due to the formation of green oil. [3] .

[0006] In recent years, single-atom metal catalysts have shown very good catalytic activity and selectivity in various heterogeneous catalytic reactions. Due to their unique physical and chemical properties and ultra-high atomic utilization efficiency, when the active site size is reduced to the single-atom level, the adsorption characteristics are completely different: from strong σ adsorption on Pd particles to weak π bonding on single atoms, which inhibits the further hydrogenation of ethylene. [4] This is because the strong adsorption ability of olefins on Pd particles becomes very weak on the surface of Pd single atoms, which can effectively inhibit the second-step hydrogenation. Xin Tao et al. [5] studied Pd single atoms and Pd nanoparticles and found that Pd single-atom catalysts showed very high acetylene semi-hydrogenation activity and selectivity, with the highest ethylene selectivity at about 82% at 200 °C. The results of DFT calculations showed that the low barrier for the hydrogenation of acetylene to ethylene and the desorption of ethylene from Pd single atoms are the keys to the high selectivity of ethylene.

[0007] However, due to the inherently low Tammann temperature and high surface energy of noble metal single atoms, they are prone to Pd sintering and growth at high temperatures during long-term operation. In addition, single-atom metal catalysts are difficult to prepare, have a very low loading amount, and insufficient stability. These factors all restrict their development. Therefore, it is of great significance to prepare Pd-based catalysts for acetylene semi-hydrogenation reactions while maintaining high catalyst activity and improving ethylene selectivity.

[0008] [1] Teschner D, Borsodi J, Wootsch A, et al. The roles of subsurface carbon and hydrogen in palladium-catalyzed alkyne hydrogenation[J]. Science, 2008, 320(5872): 86 - 89.

[0009] [2] Studt F, Abild-Pedersen F, Bligaard T, et al. Identification of non-precious metal alloy catalysts for selective hydrogenation of acetylene[J]. Science, 2008, 320(5881): 1320 - 1322.

[0010] [3] Hu M, Wang X. Effect of N3-species on selective acetylene hydrogenation over Pd / SAC catalysts[J]. Catalysis Today, 2016, 263: 98 - 104.

[0011] [4] Huang X, Xia Y, Cao Y, et al. Enhancing both selectivity and coking-resistance of a single-atom Pd1 / C3N4 catalyst for acetylene hydrogenation[J]. Nano Research, 2017, 10: 1302 - 1312.

[0012] [5] Tao X, Nan B, Li Y, et al. Highly Active Isolated Single-Atom Pd Catalyst Supported on Layered MgO for Semihydrogenation of Acetylene[J]. ACS Applied Energy Materials, 2022, 5(9): 10385 - 10390. Summary of the Invention

[0013] In order to solve the problems existing in the prior art, the present invention aims to provide an application of a boron nitride-coated metal catalyst in the catalytic selective hydrogenation reaction of acetylene, which has excellent catalytic activity and ethylene selectivity.

[0014] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0015] Application of a boron nitride-coated metal catalyst in the catalytic selective hydrogenation of acetylene. The boron nitride-coated metal catalyst (M@BN) is prepared by two-step heat treatment using sodium amide (NaNH2), sodium borohydride (NaBH4), and a metal salt as reaction raw materials under an inert atmosphere, and is loaded into an atmospheric fixed-bed reactor for the catalytic selective hydrogenation of acetylene.

[0016] The M@BN catalyst is a nano-porous and highly crystalline h-BN-derived strong metal-support interaction type nano-catalyst constructed by in-situ encapsulation and reduction of an inorganic salt mixture, with metal nanoparticles uniformly dispersed and coated by h-BN nanosheets.

[0017] Preferably, the metal in the boron nitride-coated metal catalyst is at least one of palladium, platinum, gold, nickel, copper, zinc, ruthenium, and iridium, and the metal accounts for 0.5 - 7 wt% of the boron nitride content; more preferably 1 - 3 wt%.

[0018] Preferably, the inert atmosphere is a nitrogen, argon, or helium atmosphere.

[0019] Preferably, the metal salt is at least one of palladium chloride (PdCl2), platinum tetrachloride (PtCl4), gold trichloride (AuCl3), nickel chloride (NiCl2), copper chloride (CuCl2), zinc chloride (ZnCl2), ruthenium chloride (RuCl3), and iridium chloride (IrCl3).

[0020] Preferably, the process of the two-step heat treatment is: first maintain at 500 °C for 1 h, and then maintain at 850 °C for 2 h.

[0021] Preferably, the raw material gas for the acetylene selective hydrogenation reaction is acetylene and hydrogen, with nitrogen or helium as the balance gas, and the space velocity is 56000 - 144000 mL·g -1 ·h -1 , and the reaction temperature is 30 - 200 °C.

[0022] The beneficial effects of the present invention are as follows:

[0023] In the M@BN material, the nano-porous structure of the outer-layer coated h-BN is well retained, enabling gas acetylene molecules to fully approach the M active metal centers exposed in the form of single atoms, which helps to improve catalytic selectivity. At the same time, the existence in the form of M nanoparticles can provide more single-atom type active centers, which helps to improve catalytic activity; in addition, the metal nanoparticles coated by h-BN are highly dispersed and physically isolated in a limited space, with high thermal stability, effectively preventing the sintering and aggregation commonly present in metal nanoparticles in the practical application of metal catalysts, and overall improving the catalytic stability of the catalyst. Description of the Drawings

[0024] Figure 1 TEM image and Mapping image of 1Pd@BN in Example 1;

[0025] Figure 2 Particle size distribution diagram of 1Pd@BN in Example 1;

[0026] Figure 3 XRD patterns of xPd@BN with different Pd contents in Examples 1-3 and Comparative Example 1:

[0027] Figure 4 Catalytic performance of xPd@BN with different Pd contents in acetylene selective hydrogenation reaction in Examples 1-3;

[0028] Figure 5 Catalytic performance of 1Pd@BN in acetylene selective hydrogenation reaction under different space velocity conditions in Examples 1 and 4-5;

[0029] Figure 6 Catalytic performance of 1Pd@BN in acetylene selective hydrogenation reaction under different catalyst addition amounts in Examples 1 and 6-8;

[0030] Figure 7 Catalytic performance of 1Pd@BN and 1Pd / BN in acetylene selective hydrogenation reaction in Examples 4 and Comparative Example 2;

[0031] Figure 8 Catalytic performance of 1Pt@BN and 1Pt / BN in acetylene selective hydrogenation reaction in Examples 9 and Comparative Example 3;

[0032] Figure 9 Catalytic performance of 1Au@BN and 1Au / BN in acetylene selective hydrogenation reaction in Examples 10 and Comparative Example 4;

[0033] Figure 10 Catalytic performance of 1Ni@BN and 1Ni / BN in acetylene selective hydrogenation reaction in Examples 11 and Comparative Example 5;

[0034] Figure 11 Catalytic performance of 1Cu@BN and 1Cu / BN in acetylene selective hydrogenation reaction in Examples 12 and Comparative Example 6;

[0035] Figure 12 Catalytic performance of 1Zn@BN and 1Zn / BN in acetylene selective hydrogenation reaction in Examples 13 and Comparative Example 7;

[0036] Figure 13In Examples 14 and Comparative Example 8, the catalytic performances of 1Ru@BN and 1Ru / BN in the acetylene selective hydrogenation reaction;

[0037] Figure 14 In Examples 15 and Comparative Example 9, the catalytic performances of 1Ir@BN and 1Ir / BN in the acetylene selective hydrogenation reaction. Detailed implementation manners

[0038] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the exemplified embodiments are not intended to limit the present invention.

[0039] Example 1

[0040] Weigh 3.0 g of sodium amide powder (NaNH2), 3.0 g of sodium borohydride powder (NaBH4) and 32.04 mg of palladium chloride (PdCl2) in a nickel mortar in a glove box. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Subsequently, place them in a tubular furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it multiple times, and place it in a vacuum oven to dry overnight. The catalyst is labeled as: 1Pd@BN, and the Pd loading is detected by ICP-OES to be 0.96 wt%.

[0041] Perform transmission electron microscopy analysis on 1Pd@BN, and the results are as Figure 2 shown, with a particle size of 1.0 - 4.0 nm.

[0042] Evaluate the catalytic performance of the 1Pd@BN catalyst in the acetylene selective hydrogenation reaction in an atmospheric pressure fixed-bed reactor. Take an equal mass of quartz sand (SiO2, 60 - 80 mesh) to dilute 30 mg of the catalyst, and fix the catalyst bed with quartz wool in a quartz reaction tube (i.d. = 10 mm). The reaction feed gas composition is: 5 vol.% acetylene (C2H2), 5 vol.% hydrogen (H2), and nitrogen (N2) as the balance gas. The space velocity is controlled at 100000 mL·g -1 ·h -1 , the reaction pressure is 0.1 MPa, and the reaction temperature is controlled at 30 - 200 °C. The gas products are separated and detected online by a gas chromatograph (Agilent 8860), which is equipped with an alumina-packed column and a flame ionization detector (FID). Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 100%, and the ethylene yield is 82.21%.

[0043] Example 2

[0044] Weigh 3.0 g of sodium amide powder (NaNH₂), 3.0 g of sodium borohydride powder (NaBH₄), and 16.02 mg of palladium chloride (PdCl₂) in a nickel mortar in a glove box. Grind the above raw materials thoroughly until homogeneous, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first, heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it multiple times, and place it in a vacuum oven to dry overnight. The catalyst is labeled as 0.5Pd@BN, and the Pd loading is detected by ICP - OES to be 0.47 wt%.

[0045] Evaluate the catalytic performance of the 0.5Pd@BN catalyst in the selective hydrogenation of acetylene in an atmospheric - pressure fixed - bed reactor. Similar to Example 1, through analysis and calculation, it is obtained that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 97.05%, and the ethylene yield is 75.55%.

[0046] Example 3

[0047] Weigh 3.0 g of sodium amide powder (NaNH₂), 3.0 g of sodium borohydride powder (NaBH₄), and 96.13 mg of palladium chloride (PdCl₂) in a nickel mortar in a glove box. Grind the above raw materials thoroughly until homogeneous, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first, heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it multiple times, and place it in a vacuum oven to dry overnight. The catalyst is labeled as 3Pd@BN, and the Pd loading is detected by ICP - OES to be 2.77 wt%.

[0048] Evaluate the catalytic performance of the 3Pd@BN catalyst in the selective hydrogenation of acetylene in an atmospheric - pressure fixed - bed reactor. Similar to Example 1, through analysis and calculation, it is obtained that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 100%, and the ethylene yield is 80.20%.

[0049] Example 4

[0050] The catalyst is prepared in the same way as in Example 1.

[0051] Evaluate the catalytic performance of the 1Pd@BN catalyst in the selective hydrogenation of acetylene in an atmospheric - pressure fixed - bed reactor. Similar to Example 1, the only difference is that the space velocity is controlled at 56000 mL·g -1 ·h -1 , through analysis and calculation, it is obtained that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 100%, and the ethylene yield is 94.03%.

[0052] Example 5

[0053] The catalyst was prepared in the same manner as in Example 1.

[0054] The catalytic performance of the 1Pd@BN catalyst in the selective hydrogenation of acetylene was evaluated in an atmospheric-pressure fixed-bed reactor. The procedure was the same as in Example 1, except that the space velocity was controlled at 144000 mL·g -1 ·h -1 . Through analysis and calculation, it was found that when the reaction temperature reached 200 °C, the conversion rate of acetylene was 100%, and the ethylene yield was 79.69%.

[0055] Example 6

[0056] The catalyst was prepared in the same manner as in Example 1.

[0057] The catalytic performance of the 1Pd@BN catalyst in the selective hydrogenation of acetylene was evaluated in an atmospheric-pressure fixed-bed reactor. The procedure was the same as in Example 4, except that an equal mass of quartz sand (SiO2, 60 - 80 mesh) was used to dilute 15 mg of the catalyst. Through analysis and calculation, it was found that when the reaction temperature reached 200 °C, the conversion rate of acetylene was 89.56%, and the ethylene yield was 85.99%.

[0058] Example 7

[0059] The catalyst was prepared in the same manner as in Example 1.

[0060] The catalytic performance of the 1Pd@BN catalyst in the selective hydrogenation of acetylene was evaluated in an atmospheric-pressure fixed-bed reactor. The procedure was the same as in Example 4, except that an equal mass of quartz sand (SiO2, 60 - 80 mesh) was used to dilute 60 mg of the catalyst. Through analysis and calculation, it was found that when the reaction temperature reached 200 °C, the conversion rate of acetylene was 100%, and the ethylene yield was 90.77%.

[0061] Example 8

[0062] The catalyst was prepared in the same manner as in Example 1.

[0063] The catalytic performance of the 1Pd@BN catalyst in the selective hydrogenation of acetylene was evaluated in an atmospheric-pressure fixed-bed reactor. The procedure was the same as in Example 4, except that an equal mass of quartz sand (SiO2, 60 - 80 mesh) was used to dilute 90 mg of the catalyst. Through analysis and calculation, it was found that when the reaction temperature reached 200 °C, the conversion rate of acetylene was 100%, and the ethylene yield was 89.27%.

[0064] Example 9

[0065] Weigh 3.0 g of sodium amide powder (NaNH2), 3.0 g of sodium borohydride powder (NaBH4), and 32.96 mg of platinum(IV) chloride (PtCl4) in a glove box into a nickel mortar. Grind the above raw materials thoroughly until homogeneous, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first, heat up to 500 °C and maintain for 1 h, and then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it several times, and dry it overnight in a vacuum oven. The catalyst is labeled as: 1Pt@BN, and the Pt loading is detected by ICP-OES to be 0.90 wt%.

[0066] Same as Example 8, evaluate the catalytic performance of the 1Pt@BN catalyst in the acetylene selective hydrogenation reaction in an atmospheric-pressure fixed-bed reactor. Analysis and calculation show that: when the reaction temperature reaches 200 °C, the acetylene conversion rate is 88.90%, and the ethylene yield is 74.70%.

[0067] Example 10

[0068] Weigh 3.0 g of sodium amide powder (NaNH2), 3.0 g of sodium borohydride powder (NaBH4), and 29.39 mg of gold(III) chloride (AuCl3) in a glove box into a nickel mortar. Grind the above raw materials thoroughly until homogeneous, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first, heat up to 500 °C and maintain for 1 h, and then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it several times, and dry it overnight in a vacuum oven. The catalyst is labeled as: 1Au@BN, and the Au loading is detected by ICP-OES to be 0.90 wt%.

[0069] Same as Example 8, evaluate the catalytic performance of the 1Au@BN catalyst in the acetylene selective hydrogenation reaction in an atmospheric-pressure fixed-bed reactor. Analysis and calculation show that: when the reaction temperature reaches 200 °C, the acetylene conversion rate is 82.90%, and the ethylene yield is 61.37%.

[0070] Example 11

[0071] Weigh 3.0 g of sodium amide powder (NaNH2), 3.0 g of sodium borohydride powder (NaBH4), and 42.14 mg of nickel chloride (NiCl2) in a glove box into a nickel mortar. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Subsequently, place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first, heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it multiple times, and dry it overnight in a vacuum oven. The catalyst is labeled as: 1Ni@BN. The loading of Ni detected by ICP-OES is 0.93 wt%.

[0072] Same as Example 8, evaluate the catalytic performance of the 1Ni@BN catalyst in the acetylene selective hydrogenation reaction in an atmospheric pressure fixed bed reactor. Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 82.90%, and the ethylene yield is 61.37%.

[0073] Example 12

[0074] Weigh 3.0 g of sodium amide powder (NaNH2), 3.0 g of sodium borohydride powder (NaBH4), and 40.38 mg of copper chloride (CuCl2) in a glove box into a nickel mortar. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Subsequently, place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first, heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it multiple times, and dry it overnight in a vacuum oven. The catalyst is labeled as: 1Cu@BN. The loading of Cu detected by ICP-OES is 0.91 wt%.

[0075] Same as Example 8, evaluate the catalytic performance of the 1Cu@BN catalyst in the acetylene selective hydrogenation reaction in an atmospheric pressure fixed bed reactor. Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 76.90%, and the ethylene yield is 65.39%.

[0076] Example 13

[0077] Weigh 3.0 g of sodium amide powder (NaNH₂), 3.0 g of sodium borohydride powder (NaBH₄), and 39.79 mg of zinc chloride (ZnCl₂) in a nickel mortar in a glove box. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Subsequently, place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first, heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it multiple times, and place it in a vacuum oven to dry overnight. The catalyst is labeled as: 1Zn@BN, and the loading amount of Zn detected by ICP - OES is 0.92 wt%.

[0078] Same as Example 8, evaluate the catalytic performance of the 1Zn@BN catalyst in the acetylene selective hydrogenation reaction in an atmospheric pressure fixed - bed reactor. Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 95.90%, and the ethylene yield is 72.91%.

[0079] Example 14

[0080] Weigh 3.0 g of sodium amide powder (NaNH₂), 3.0 g of sodium borohydride powder (NaBH₄), and 39.17 mg of ruthenium chloride (RuCl₃) in a nickel mortar in a glove box. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Subsequently, place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first, heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it multiple times, and place it in a vacuum oven to dry overnight. The catalyst is labeled as: 1Ru@BN, and the loading amount of Ru detected by ICP - OES is 0.93 wt%.

[0081] Same as Example 8, evaluate the catalytic performance of the 1Ru@BN catalyst in the acetylene selective hydrogenation reaction in an atmospheric pressure fixed - bed reactor. Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 88.90%, and the ethylene yield is 72.93%.

[0082] Example 15

[0083] In a glove box, weigh 3.0g of sodium amide powder (NaNH2), 3.0g of sodium borohydride powder (NaBH4) and 31.43mg of iridium chloride (IrCl3) in a nickel mortar, grind the above raw materials until they are uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place it in a tubular furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is: first heat it to 500°C and maintain it for 1h, then continue to heat it to 850°C and maintain it for 2h. After the heat treatment, the sample is washed and centrifuged several times, and placed in a vacuum oven to dry overnight. The catalyst is labeled: 1Ir@BN, and the Ir loading is 0.95wt% as detected by ICP-OES.

[0084] Similar to Example 8, the catalytic performance of 1Ir@BN catalyst in the selective hydrogenation of acetylene was evaluated in a fixed bed reactor at atmospheric pressure. Analysis and calculation showed that when the reaction temperature reached 200°C, the acetylene conversion rate was 70.90% and the ethylene yield was 47.52%.

[0085] Comparative Example 1

[0086] In a glove box, weigh 3g of sodium amide powder (NaNH2) and 3g of sodium borohydride powder (NaBH4) in a nickel mortar, grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with nitrogen atmosphere for later use. Then place it in a tubular furnace filled with nitrogen atmosphere for heat treatment. The specific heat treatment procedure is: first heat up to 500℃ and maintain for 1h, then continue to heat up to 850℃ and maintain for 2h. After the heat treatment, the sample is washed and centrifuged several times, and placed in a vacuum oven to dry overnight. Marked as: boron nitride (h-BN).

[0087] ICP-OES analysis showed that the Pd loading in BN was 0 wt %.

[0088] The catalytic performance of the BN catalyst in the selective hydrogenation of acetylene was evaluated in a fixed bed reactor at atmospheric pressure, as in Example 4. Analysis and calculation showed that when the reaction temperature reached 200°C, the acetylene conversion rate was 12.00% and the ethylene yield was 4.67%.

[0089] Comparative Example 2

[0090] In a glove box, weigh 3.0g of sodium amide powder (NaNH2) and 3.0g of sodium borohydride powder (NaBH4) in a nickel mortar, grind the above raw materials until they are uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place it in a tubular furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is: first heat it to 500℃ and maintain it for 1h, then continue to heat it to 850℃ and maintain it for 2h. After the heat treatment, the sample is washed and centrifuged several times, and placed in a vacuum oven to dry overnight. Marked as: boron nitride (h-BN).

[0091] Subsequently, the 1Pd / BN catalyst was prepared by an impregnation-calcination-reduction method. The specific preparation process is as follows:

[0092] (1) Weigh 1.0 g of boron nitride powder (h-BN) and 16.67 mg of palladium chloride (PdCl2), dissolve them in 50 mL of ethanol solution, stir well at 50 °C until the ethanol is completely evaporated, collect the precipitate, wash it with water and centrifuge it several times, and then place it in a vacuum oven and dry it overnight at 60 °C;

[0093] (2) Take the powder sample obtained in step (1) and calcine it at 400 °C for 4 h in an air atmosphere;

[0094] (3) Take the powder sample obtained in step (2) and reduce it at 200 °C for 2 h in a 5% H2 / 95% Ar atmosphere, collect the sample and label it as: 1Pd / BN.

[0095] Detected by ICP-OES, the Pd loading in 1Pd / BN is 0.93 wt%.

[0096] Same as Example 4, the catalytic performance of the 1Pd / BN catalyst in the acetylene selective hydrogenation reaction was evaluated in a fixed-bed reactor under atmospheric pressure. Analysis and calculation showed that when the reaction temperature reached 200 °C, the acetylene conversion was 100%, and the ethylene yield was 40.84%.

[0097] Comparative Example 3

[0098] Weigh 3.0 g of sodium amide powder (NaNH2) and 3.0 g of sodium borohydride powder (NaBH4) in a nickel mortar in a glove box, grind the above raw materials thoroughly until uniform, put them into a reagent bottle filled with a nitrogen atmosphere and store for later use. Subsequently, it was placed in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure was as follows: first, heat up to 500 °C and maintain for 1 h, and then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, the sample was washed with water and centrifuged several times, and placed in a vacuum oven and dried overnight. Labeled as: boron nitride (h-BN).

[0099] Subsequently, the 1Pt / BN catalyst was prepared by an impregnation-calcination-reduction method. The specific preparation process is as follows:

[0100] (1) Weigh 1.0 g of boron nitride powder (h-BN) and 17.27 mg of palladium chloride (PtCl4), dissolve them in 50 mL of ethanol solution, stir well at 50 °C until the ethanol is completely evaporated, collect the precipitate, wash it with water and centrifuge it several times, and then place it in a vacuum oven and dry it overnight at 60 °C;

[0101] (2) Take the powder sample obtained in step (1) and calcine it at 400 °C for 4 h in an air atmosphere;

[0102] (3) Take the powder sample obtained in step (2) and reduce it at 200 °C for 2 h in a 5% H2 / 95% Ar atmosphere. Collect the sample and label it as: 1Pt / BN.

[0103] As detected by ICP-OES, the Pd loading in 1Pt / BN is 0.95 wt%.

[0104] Evaluate the catalytic performance of the 1Pt / BN catalyst in the selective hydrogenation of acetylene in a fixed-bed reactor under atmospheric pressure. Take an equal mass of quartz sand (SiO2, 60 - 80 mesh) to dilute 30 mg of the catalyst, and fix the catalyst bed with quartz wool in a quartz reaction tube (i.d. = 10 mm). The reaction feed gas composition is: 5 vol.% acetylene (C2H2), 5 vol.% hydrogen (H2), and nitrogen (N2) as the balance gas. The space velocity is controlled at 56000 mL·g -1 ·h -1 , the reaction pressure is 0.1 MPa, and the reaction temperature is controlled at 30 - 200 °C. The gas products are separated and detected online by a gas chromatograph (Agilent 8860), which is equipped with an alumina-packed column and a flame ionization detector (FID). Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 90.57% and the ethylene yield is 27.62%.

[0105] Comparative Example 4

[0106] Weigh 3.0 g of sodium amide powder (NaNH2) and 3.0 g of sodium borohydride powder (NaBH4) in a nickel mortar in a glove box. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is: first heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it several times, and then dry it overnight in a vacuum oven. Label it as: boron nitride (h-BN).

[0107] Immediately afterwards, prepare the 1Au / BN catalyst by the impregnation-calcination-reduction method. The specific preparation process is as follows:

[0108] (1) Weigh 1.0 g of boron nitride powder (h-BN) and 15.40 mg of gold chloride (AuCl3) and dissolve them in 50 mL of ethanol solution. Stir well at 50 °C until the ethanol completely evaporates. Collect the precipitate, wash it with water and centrifuge it several times, and then dry it overnight at 60 °C in a vacuum oven;

[0109] (2) Take the powder sample obtained in step (1) and calcine it at 400 °C for 4 h in an air atmosphere;

[0110] (3) Take the powder sample obtained in step (2) and reduce it at 200 °C for 2 h in a 5% H2 / 95% Ar atmosphere. Collect the sample and label it as: 1Au / BN.

[0111] As detected by ICP-OES, the Au loading in 1Au / BN is 0.95 wt%.

[0112] Evaluate the catalytic performance of the 1Au / BN catalyst in the selective hydrogenation of acetylene in a fixed-bed reactor under atmospheric pressure. Take an equal mass of quartz sand (SiO2, 60 - 80 mesh) to dilute 30 mg of the catalyst, and fix the catalyst bed in a quartz reaction tube (i.d. = 10 mm) with quartz wool. The reaction feed gas composition is: 5 vol.% acetylene (C2H2), 5 vol.% hydrogen (H2), and nitrogen (N2) as the balance gas. The space velocity is controlled at 56000 mL·g -1 ·h -1 , the reaction pressure is 0.1 MPa, and the reaction temperature is controlled at 30 - 200 °C. The gas products are separated and detected online by a gas chromatograph (Agilent 8860), which is equipped with an alumina packed column and a flame ionization detector (FID). Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 86.57% and the ethylene yield is 9.08%.

[0113] Comparative Example 5

[0114] Weigh 3.0 g of sodium amide powder (NaNH2) and 3.0 g of sodium borohydride powder (NaBH4) in a nickel mortar in a glove box. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash and centrifuge the sample several times, and place it in a vacuum oven to dry overnight. Label it as: hexagonal boron nitride (h-BN).

[0115] Immediately afterwards, prepare the 1Ni / BN catalyst by the impregnation-calcination-reduction method. The specific preparation process is as follows:

[0116] (1) Weigh 1.0 g of hexagonal boron nitride powder (h-BN) and 22.08 mg of nickel chloride (NiCl2) and dissolve them in 50 mL of ethanol solution. Stir well at 50 °C until the ethanol is completely evaporated. Collect the precipitate, wash and centrifuge it several times, and then place it in a vacuum oven to dry overnight at 60 °C;

[0117] (2) Take the powder sample obtained in step (1) and calcine it at 400 °C for 4 h in an air atmosphere;

[0118] (3) Take the powder sample obtained in step (2) and reduce it at 200 °C for 2 h under a 5% H2 / 95% Ar atmosphere. Collect the sample and label it as: 1Ni / BN.

[0119] By ICP-OES detection, the Ni loading in 1Ni / BN is 0.95 wt%.

[0120] Evaluate the catalytic performance of the 1Pt / BN catalyst in the selective hydrogenation of acetylene in a fixed-bed reactor under atmospheric pressure. Take an equal mass of quartz sand (SiO2, 60 - 80 mesh) to dilute 30 mg of the catalyst, and fix the catalyst bed with quartz wool in a quartz reaction tube (i.d. = 10 mm). The reaction feed gas composition is: 5 vol.% acetylene (C2H2), 5 vol.% hydrogen (H2), and nitrogen (N2) as the balance gas. The space velocity is controlled at 56000 mL·g -1 ·h -1 -1·h-1, the reaction pressure is 0.1 MPa, and the reaction temperature is controlled at 30 - 200 °C. The gas products are separated and detected online by a gas chromatograph (Agilent 8860), which is equipped with an alumina-packed column and a flame ionization detector (FID). Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 67.57%, and the ethylene yield is 13.85%.

[0121] Comparative Example 6

[0122] Weigh 3.0 g of sodium amide powder (NaNH2) and 3.0 g of sodium borohydride powder (NaBH4) in a nickel mortar in a glove box. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it several times, and then dry it overnight in a vacuum oven. Label it as: hexagonal boron nitride (h-BN).

[0123] Immediately afterwards, prepare the 1Cu / BN catalyst by the impregnation-calcination-reduction method. The specific preparation process is as follows:

[0124] (1) Weigh 1.0 g of hexagonal boron nitride powder (h-BN) and 21.16 mg of copper chloride (CuCl2) and dissolve them in 50 mL of ethanol solution. Stir well at 50 °C until the ethanol completely evaporates. Collect the precipitate, wash it with water and centrifuge it several times, and then dry it overnight in a vacuum oven at 60 °C;

[0125] (2) Take the powder sample obtained in step (1) and calcine it at 400 °C for 4 h in an air atmosphere;

[0126] (3) Take the powder sample obtained in step (2) and reduce it at 200 °C for 2 h in a 5% H2 / 95% Ar atmosphere. Collect the sample and label it as: 1Cu / BN.

[0127] Detected by ICP-OES, the Cu loading in 1Cu / BN is 0.94 wt%.

[0128] Evaluate the catalytic performance of the 1Cu / BN catalyst in the selective hydrogenation of acetylene in a fixed-bed reactor under atmospheric pressure. Take an equal mass of quartz sand (SiO2, 60 - 80 mesh) to dilute 30 mg of the catalyst, and fix the catalyst bed in a quartz reaction tube (i.d. = 10 mm) with quartz wool. The reaction feed gas composition is: 5 vol.% acetylene (C2H2), 5 vol.% hydrogen (H2), and nitrogen (N2) as the balance gas. The space velocity is controlled at 56000 mL·g -1 ·h -1 , the reaction pressure is 0.1 MPa, and the reaction temperature is controlled at 30 - 200 °C. The gas products are separated and detected online by a gas chromatograph (Agilent 8860), which is equipped with an alumina-packed column and a flame ionization detector (FID). Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 35.57%, and the ethylene yield is 17.96%.

[0129] Comparative Example 7

[0130] Weigh 3.0 g of sodium amide powder (NaNH2) and 3.0 g of sodium borohydride powder (NaBH4) in a nickel mortar in the glove box. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash and centrifuge the sample several times, and place it in a vacuum oven to dry overnight. Label it as: boron nitride (h-BN).

[0131] Immediately afterwards, prepare the 1Zn / BN catalyst by the impregnation-calcination-reduction method. The specific preparation process is as follows:

[0132] (1) Weigh 1.0 g of boron nitride powder (h-BN) and 20.85 mg of zinc chloride (ZnCl2) and dissolve them in 50 mL of ethanol solution. Stir well at 50 °C until the ethanol completely evaporates. Collect the precipitate, wash and centrifuge it several times, and then place it in a vacuum oven to dry overnight at 60 °C;

[0133] (2) Take the powder sample obtained in step (1) and calcine it at 400 °C for 4 h in an air atmosphere;

[0134] (3) Take the powder sample obtained in step (2) and reduce it at 200 °C for 2 h in a 5% H2 / 95% Ar atmosphere. Collect the sample and label it as: 1Zn / BN.

[0135] As detected by ICP-OES, the Zn loading in 1Zn / BN is 0.94 wt%.

[0136] Evaluate the catalytic performance of the 1Cu / BN catalyst in the selective hydrogenation of acetylene in a fixed-bed reactor under atmospheric pressure. Take an equal mass of quartz sand (SiO2, 60 - 80 mesh) to dilute 30 mg of the catalyst, and fix the catalyst bed in a quartz reaction tube (i.d. = 10 mm) with quartz wool. The reaction feed gas composition is: 5 vol.% acetylene (C2H2), 5 vol.% hydrogen (H2), and nitrogen (N2) as the balance gas. The space velocity is controlled at 56000 mL·g -1 ·h -1 , the reaction pressure is 0.1 MPa, and the reaction temperature is controlled at 30 - 200 °C. The gas products are separated and detected online by a gas chromatograph (Agilent 8860), which is equipped with an alumina-packed column and a flame ionization detector (FID). Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 97.57%, and the ethylene yield is 10.24%.

[0137] Comparative Example 8

[0138] Weigh 3.0 g of sodium amide powder (NaNH2) and 3.0 g of sodium borohydride powder (NaBH4) in a nickel mortar in the glove box. Grind the above raw materials thoroughly until uniform, and store them in a reagent bottle filled with a nitrogen atmosphere for later use. Then place them in a tubular furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure is as follows: first heat up to 500 °C and maintain for 1 h, then continue to heat up to 850 °C and maintain for 2 h. After the heat treatment, wash the sample with water and centrifuge it several times, and then dry it overnight in a vacuum oven. Label it as: hexagonal boron nitride (h-BN).

[0139] Immediately afterwards, prepare the 1Ru / BN catalyst by the impregnation-calcination-reduction method. The specific preparation process is as follows:

[0140] (1) Weigh 1.0 g of hexagonal boron nitride powder (h-BN) and 20.52 mg of ruthenium chloride (RuCl3) and dissolve them in 50 mL of ethanol solution. Stir well at 50 °C until the ethanol completely evaporates. Collect the precipitate, wash it with water and centrifuge it several times, and then dry it overnight at 60 °C in a vacuum oven;

[0141] (2) Take the powder sample obtained in step (1) and calcine it at 400 °C for 4 h in an air atmosphere;

[0142] (3) The powder sample obtained in step (2) was reduced at 200 °C for 2 h in a 5% H2 / 95% Ar atmosphere, and the sample was collected and labeled as: 1Ru / BN.

[0143] As detected by ICP-OES, the Ru loading in 1Ru / BN was 0.96 wt%.

[0144] The catalytic performance of the 1Ru / BN catalyst in the selective hydrogenation of acetylene was evaluated in a fixed-bed reactor under atmospheric pressure. An equal mass of quartz sand (SiO2, 60 - 80 mesh) was taken to dilute 30 mg of the catalyst, and the catalyst bed was fixed in a quartz reaction tube (i.d. = 10 mm) with quartz wool. The reaction feed gas composition was: 5 vol.% acetylene (C2H2), 5 vol.% hydrogen (H2), and nitrogen (N2) as the balance gas, and the space velocity was controlled at 56000 mL·g -1 ·h -1 , the reaction pressure was 0.1 MPa, and the reaction temperature was controlled at 30 - 200 °C. The gas products were separated and detected online by a gas chromatograph (Agilent 8860), which was equipped with an alumina-packed column and a flame ionization detector (FID). Analysis and calculation showed that when the reaction temperature reached 200 °C, the acetylene conversion was 85.57% and the ethylene yield was 17.54%.

[0145] Comparative Example 9

[0146] In the glove box, 3.0 g of sodium amide powder (NaNH2) and 3.0 g of sodium borohydride powder (NaBH4) were weighed into a nickel mortar, and the above raw materials were thoroughly ground until uniform, then stored in a reagent bottle filled with a nitrogen atmosphere for later use. Subsequently, it was placed in a tube furnace filled with a nitrogen atmosphere for heat treatment. The specific heat treatment procedure was: first heated to 500 °C and maintained for 1 h, then continued to be heated to 850 °C and maintained for 2 h. After the heat treatment, the sample was washed and centrifuged several times, and then placed in a vacuum oven to dry overnight. Labeled as: hexagonal boron nitride (h-BN).

[0147] Immediately afterwards, a 1Ir / BN catalyst was prepared by the impregnation-calcination-reduction method. The specific preparation process is as follows:

[0148] (1) Weigh 1.0 g of hexagonal boron nitride powder (h-BN) and 16.47 mg of iridium chloride (IrCl3) and dissolve them in 50 mL of ethanol solution. Stir well at 50 °C until the ethanol is completely evaporated. Collect the precipitate, wash and centrifuge it several times, and then place it in a vacuum oven to dry overnight at 60 °C;

[0149] (2) Take the powder sample obtained in step (1) and calcine it at 400 °C for 4 h in an air atmosphere;

[0150] (3) Take the powder sample obtained in step (2) and reduce it at 200 °C for 2 h in a 5% H2 / 95% Ar atmosphere. Collect the sample and label it as: 1Ir / BN.

[0151] Detected by ICP-OES, the loading of Ir in 1Ir / BN is 0.91 wt%.

[0152] Evaluate the catalytic performance of the 1Ir / BN catalyst in the selective hydrogenation of acetylene in a fixed-bed reactor under atmospheric pressure. Take an equal mass of quartz sand (SiO2, 60-80 mesh) to dilute 30 mg of the catalyst, and fix the catalyst bed with quartz wool in a quartz reaction tube (i.d. = 10 mm). The reaction feed gas composition is: 5 vol.% acetylene (C2H2), 5 vol.% hydrogen (H2), and nitrogen (N2) as the balance gas. The space velocity is controlled at 56000 mL·g -1 ·h -1 , the reaction pressure is 0.1 MPa, and the reaction temperature is controlled at 30-200 °C. The gas products are separated and detected online by a gas chromatograph (Agilent 8860), which is equipped with an alumina-packed column and a flame ionization detector (FID). Analysis and calculation show that when the reaction temperature reaches 200 °C, the acetylene conversion rate is 60.57%, and the ethylene yield is 17.26%.

[0153] From the result analysis of Comparative Examples 1-9 and Examples 1-15, it can be seen that the h-BN-coated metal nanoporous catalyst (M@BN) constructed by in-situ encapsulation and reduction of the inorganic salt mixture has appropriate metal exposure sites, and there is a strong metal-support interaction between the metal nanoparticles (NPs) and h-BN. This unique mechanism enables M@BN to exhibit excellent acetylene selective hydrogenation activity and overall improves the catalytic stability of the catalyst. In contrast, in the boron nitride-supported metal catalyst (M / BN) synthesized by the impregnation method, due to the strong adsorption of metal nanoparticles (NPs) on unsaturated reactants, the generation of the over-hydrogenation side reaction ethane of acetylene is caused, so the ethylene selectivity is poor.

Claims

1. Application of a boron nitride-coated metal catalyst in the selective hydrogenation reaction of acetylene, characterized in that: The boron nitride-coated metal catalyst is prepared by two-step heat treatment using sodium amide, sodium borohydride, and metal salts as reaction raw materials under an inert atmosphere, and is loaded into an atmospheric fixed-bed reactor for catalytic acetylene selective hydrogenation reaction; The metal in the boron nitride-coated metal catalyst is at least one of palladium, platinum, gold, nickel, copper, zinc, ruthenium, and iridium, and the metal accounts for 0.5-7 wt% of the boron nitride; The process of the two-step heat treatment is as follows: first, maintain at 500 °C for 1 h, and then maintain at 850 °C for 2 h.

2. Use of the boron nitride-coated metal catalyst according to claim 1 in the catalytic selective hydrogenation reaction of acetylene, characterized in that: The inert atmosphere is a nitrogen, argon, or helium atmosphere.

3. Use of the boron nitride-coated metal catalyst according to claim 1 in the catalytic selective hydrogenation reaction of acetylene, characterized in that: The metal salt is at least one of palladium chloride, platinum tetrachloride, gold trichloride, nickel chloride, copper chloride, zinc chloride, ruthenium chloride, and iridium chloride.

4. Use of the boron nitride-coated metal catalyst according to any one of claims 1-3 in the catalytic selective hydrogenation reaction of acetylene, characterized in that: The feed gas for the selective hydrogenation reaction of acetylene is acetylene and hydrogen, with nitrogen or helium as the balance gas, and the space velocity is 56,000 - 144,000 mL·g -1 ·h -1 , and the reaction temperature is 30 - 200 °C.

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