Supported nickel-based catalysts, methods for their preparation and use

Abstract

The disclosure provides a preparation method of a supported nickel-based catalyst, comprising the steps of: weighing the required deionized water based on the unit water absorption of gamma-Al2O3 or ZSM-5 molecular sieve as a carrier and the content of crystal water in nitrate salt, adding nickel nitrate into the deionized water, and heating and stirring until completely dissolved to prepare a salt solution; adding the molecular sieve into the salt solution and transferring to an ultrasonic machine for ultrasonic impregnation for 0.5-5 hours, and then standing for 4-20 hours after impregnation to obtain an impregnated product; drying the impregnated product at a temperature of 70-130 DEG C for 3-24 hours to obtain a dried impregnated product, and calcining the dried impregnated product at a temperature of 250-650 DEG C for 2-12 hours to obtain the supported nickel-based catalyst. The disclosure also provides the supported nickel-based catalyst prepared by the preparation method and the application of the supported nickel-based catalyst in the preparation of hexamethylenediamine from adiponitrile by hydrogenation.

Description

Technical Field

[0001] This disclosure pertains to the field of catalyst technology and relates to a supported nickel-based catalyst for the hydrogenation of adiponitrile to hexamethylenediamine, its preparation method, and its application. Background Technology

[0002] Hexamethylenediamine (HDMA), an important raw material in the chemical industry, is commonly used to synthesize polyamide nylon-66 and nylon-610. It can also be used to synthesize organic crosslinking agents, synthetic resins, surfactants, and other chemical products. It has wide applications in aerospace, automotive and electronic components, and consumer electronics, resulting in a huge market demand. The most mainstream synthesis route for HDMA is using adiponitrile and hydrogen as raw materials. The main processes for synthesizing HDMA by hydrogenation of adiponitrile include high-pressure and low-pressure methods. The high-pressure method has a high single-unit HDMA production capacity but requires stringent reaction conditions; the low-pressure method has milder reaction conditions and higher selectivity for HDMA, but has a lower single-unit HDMA production capacity.

[0003] Currently, iron and copper-based catalysts are mainly used in the high-pressure hydrogenation process of adiponitrile to synthesize hexamethylenediamine, but the harsh reaction conditions increase energy consumption during production. In the low-pressure hydrogenation process of adiponitrile to synthesize hexamethylenediamine, Raney nickel is the main catalyst, but Raney nickel catalysts have high activity, are prone to spontaneous combustion, and have poor mechanical strength, increasing safety concerns during production. Furthermore, both the low-pressure and high-pressure processes require the introduction of high-pressure ammonia or the addition of large amounts of strong alkali to suppress side reactions, increasing the difficulty of subsequent separation and raising equipment costs. Therefore, researching and developing a high-performance catalyst with high mechanical strength and good thermal stability, combining the advantages of both high-pressure and low-pressure processes, would inject new vitality into the process of hydrogenating adiponitrile to synthesize hexamethylenediamine under mild conditions, and help alleviate the current supply shortage in my country's hexamethylenediamine market.

[0004] Through research by numerous experts both domestically and internationally, some achievements have been made in the technology of hydrogenating adiponitrile to hexamethylenediamine. In 2020, the research group of Liang Changhai at Dalian University of Technology prepared a metal oxide-modified nickel-based catalyst Ni-Ce3 / Al2O3 supported on alumina and applied it to the hydrogenation of adiponitrile to hexamethylenediamine. The catalyst achieved a 100% conversion rate of adiponitrile and a high selectivity of 91% for hexamethylenediamine. In 2016, the research group of Liu Pingle at Xiangtan University prepared an acid-activated and metal-modified sepiolite-supported nickel-based catalyst K-La-Ni / ASEP and applied it to the hydrogenation of adiponitrile to hexamethylenediamine. The catalyst achieved a 90.03% conversion rate of adiponitrile and a total selectivity of 90.22% for 6-aminohexanonitrile and hexamethylenediamine, but the selectivity for hexamethylenediamine was only 27.09%. In 2018, the research group also prepared a metal-modified supported nickel-based catalyst (1%MgO-1%Cu-Ni / MWCNT) on multi-walled carbon nanotubes for the hydrogenation of adiponitrile to hexamethylenediamine. This catalyst achieved an adiponitrile conversion of 96.27% and a total selectivity of 91.22% for 6-aminohexanonitrile and hexamethylenediamine. In 2016, Rosa Adam et al. from the Leibniz Institute for Catalysis in Germany prepared an NNP-type pincer-shaped imidazole-based phosphine-ruthenium complex catalyst for the hydrogenation of adiponitrile to hexamethylenediamine. This catalyst achieved an adiponitrile conversion of over 99% and a hexamethylenediamine yield of up to 89%, but the catalyst preparation process was cumbersome and lengthy. Therefore, developing a simple adiponitrile hydrogenation catalyst with mild reaction conditions, high catalytic activity, and high hexamethylenediamine selectivity is a pressing technical challenge.

[0005] Chinese patent CN107812534A discloses a supported nickel-based catalyst using silanized modified mesoporous silica as a support, prepared by an equal-volume impregnation method. The supported nickel-based catalyst used in this patent achieves a high adiponitrile conversion rate of up to 99.6%, but does not obtain high hexamethylenediamine selectivity, and the byproduct selectivity is relatively high. Chinese patent CN115646508A discloses a supported Ni-Ru catalyst using γ-Al₂O₃ as a support. The catalyst used in this patent achieves a high adiponitrile conversion rate of up to 100% and a hexamethylenediamine selectivity of 95.4%, but the content of the noble metal Ru in the catalyst significantly affects the hexamethylenediamine selectivity, thus the catalyst cost is relatively high.

[0006] Therefore, developing an adiponitrile hydrogenation catalyst with high catalytic activity, mild reaction conditions, good thermal stability, and no need for the addition of strong base promoters is an urgent problem to be solved in this field. Summary of the Invention

[0007] The purpose of this invention is to provide a method for preparing a supported nickel-based catalyst.

[0008] Another object of the present invention is to provide a supported nickel-based catalyst prepared by the method of the above-mentioned supported nickel-based catalyst, which has the advantages of high catalytic activity, mild reaction conditions, good thermal stability and no need to add strong base promoters in the hydrogenation reaction of adiponitrile.

[0009] Another object of the present invention is to provide the application of the supported nickel-based catalyst in the hydrogenation of adiponitrile to hexamethylenediamine.

[0010] To achieve the above objectives, the present invention provides a method for preparing a supported nickel-based catalyst. The preparation method includes the following steps:

[0011] Based on the unit water absorption capacity of the molecular sieve as the carrier and the crystal water content in the nitrate, the required amount of deionized water is weighed, nickel nitrate is added to the deionized water, and heated and stirred until completely dissolved to prepare a salt solution; wherein the molecular sieve includes γ-Al2O3 molecular sieve or ZSM-5 molecular sieve.

[0012] The molecular sieve is added to a salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 0.5 to 5 hours. After impregnation, it is left to stand for 4 to 20 hours to obtain the impregnated material.

[0013] The impregnated material is dried for 3 to 24 hours at a temperature between 70°C and 130°C to obtain a dried impregnated material.

[0014] The dried impregnated material is calcined for 2 to 12 hours at a temperature between 250°C and 650°C to obtain the supported nickel-based catalyst.

[0015] In one specific embodiment, the nickel nitrate is nickel nitrate hexahydrate, and the mass of nickel in the supported nickel-based catalyst is between 5% and 50% based on the total mass of the supported nickel-based catalyst.

[0016] In one specific embodiment, the step of adding the nickel nitrate to the deionized water further includes: adding a metal modifier nitrate to the deionized water, wherein the metal modifier nitrate is selected from the group consisting of sodium nitrate, cerium nitrate hexahydrate, magnesium nitrate hexahydrate, copper nitrate trihydrate, calcium nitrate tetrahydrate, and zinc nitrate hexahydrate, and the total mass of sodium oxide, cerium dioxide, magnesium oxide, copper, calcium oxide, and zinc oxide produced by the reaction is between 0.1% and 10% based on the total mass of the supported nickel-based catalyst.

[0017] In one specific embodiment, in the step of heating and stirring until completely dissolved, the heating temperature is between 30°C and 110°C, and the heating time is between 3 min and 30 min.

[0018] In one specific embodiment, the water absorption capacity per gram of the carrier is 0.3 mL to 4 mL of water when it is a γ-Al2O3 molecular sieve, and the water absorption capacity per gram of the carrier is 0.5 mL to 5 mL of water when it is a ZSM-5 molecular sieve.

[0019] In one specific embodiment, the ZSM-5 molecular sieve is prepared by the following steps:

[0020] Tetraethyl orthosilicate, aluminum isopropoxide, tetrapropylammonium hydroxide, sodium hydroxide, and deionized water are weighed in sequence according to a molar ratio of 500:(1 to 50):150:50:10000.

[0021] The sodium hydroxide is added to the deionized water and stirred until completely dissolved. Then, the tetrapropylammonium hydroxide is added dropwise and stirred continuously at room temperature for 0 to 2 hours to form a mixed solution.

[0022] The aluminum isopropoxide is added to the mixed solution and stirred continuously for 2 to 4 hours until the aluminum isopropoxide is completely dissolved. Then, the tetraethyl orthosilicate is added dropwise and stirred continuously for 10 to 20 hours to prepare a suspension and disperse it fully.

[0023] The suspension is transferred to a hydrothermal crystallization vessel, the vessel is sealed, and the suspension is liquidized for 12 to 72 hours at a temperature of 60°C to 220°C and a rotation speed of 30 r / min to 120 r / min to obtain a crystallized product.

[0024] The crystallized product, after centrifugal washing, is dried at a temperature of 70°C to 130°C for 3 to 24 hours to obtain a dried crystallized product; and

[0025] The dried crystallized product is calcined for 2 to 12 hours at 250°C to 650°C and then ground and sieved to 20 to 100 mesh to obtain the ZSM-5 molecular sieve.

[0026] The present invention further provides a supported nickel-based catalyst prepared by the method described above, the supported nickel-based catalyst comprising a support and an active metal, wherein the support comprises γ-Al2O3 molecular sieve or ZSM-5 molecular sieve; the active metal comprises nickel; and the mass of the support is between 60% and 80% based on the total mass of the supported nickel-based catalyst, and the mass of the active metal is between 15% and 40%.

[0027] In one specific embodiment, the γ-Al₂O₃ or ZSM-5 molecular sieve support in the supported nickel-based catalyst provides a suitable pore structure and framework, enabling the active component to be stably supported on or within the support. The active metal provides sufficient hydrogenation sites for the hydrogenation of adiponitrile to hexamethylenediamine. The metal modifier promotes the dispersion of the active metal, improves the hydrogenation activity of the supported nickel-based catalyst, and provides an appropriate amount of basic sites to enhance the selectivity of the supported nickel-based catalyst for hexamethylenediamine.

[0028] In one specific embodiment, the supported nickel-based catalyst is in the shape of amorphous solid particles, and the size of the particles is between 150 μm and 850 μm.

[0029] In one specific embodiment, the pore volume distribution of the supported nickel-based catalyst, which is supported on γ-Al₂O₃ molecular sieve, is in the range of 0.10 cm⁻¹. 3 / g and 0.50cm 3 The specific surface area distribution ranges from / g to between 10m². 2 / g and 300m 2 The average pore size distribution ranges between 3 nm and 15 nm; and the pore volume distribution of the supported nickel-based catalyst with ZSM-5 molecular sieve is between 0.05 cm³ / g. 3 / g and 0.30cm 3 The specific surface area distribution ranges from / g to between 20m². 2 / g and 400m 2 The average pore size distribution ranges from 2nm to 11nm, and the silicon-to-aluminum ratio is between 20 and 500.

[0030] In one specific embodiment, the supported nickel-based catalyst further comprises a metal modifier, the metal modifier comprising at least one of oxides of sodium, magnesium, cerium, calcium or zinc and copper; wherein the mass of the metal modifier is between 0.1% and 10% based on the total mass of the supported nickel-based catalyst.

[0031] The present invention further provides the application of the supported nickel-based catalyst in the hydrogenation of adiponitrile to hexamethylenediamine, the application being carried out through the following steps:

[0032] The supported nickel-based catalyst is packed into the isothermal section of a fixed-bed tubular reactor. A mixed gas flow of hydrogen and nitrogen is introduced, and the supported nickel-based catalyst is heated from room temperature to the temperature required for reduction at a heating rate of 1°C / min to 10°C / min, thus initiating the reduction process.

[0033] The temperature was then adjusted to the required reaction temperature. The nitrogen gas supply was stopped and the flushing pipeline was switched to a pure hydrogen gas flow. After flushing, the hydrogen gas was used to pressurize the pipeline and adjust it to the required reaction pressure. The flow rate of the hydrogen gas was set, and a mixed solution of adiponitrile and solvent in a certain proportion was introduced to start the reaction. After the reaction product was separated into gas and liquid phases, the liquid phase product was analyzed, and the catalytic performance of the supported nickel-based catalyst was evaluated based on the analysis results.

[0034] In one specific embodiment, the reduction conditions are as follows: at atmospheric pressure, the reduction is carried out using a mixed gas flow of hydrogen and nitrogen; the reduction time is between 2 hours and 10 hours; the reduction temperature is between 300°C and 500°C; the flow rate of hydrogen is between 10 mL / min and 100 mL / min; the flow rate of nitrogen is between 10 mL / min and 100 mL / min; the flow rate of pure hydrogen gas in the flushing pipeline is between 10 mL / min and 200 mL / min; and the flushing time of the flushing pipeline is between 3 min and 30 min.

[0035] In one specific embodiment, the reaction temperature is between 40°C and 180°C, the reaction pressure is between 0.5 MPa and 10 MPa, and the mass hourly space velocity (WHSV) of the adiponitrile is between 0.1 h⁻¹. -1 With 10h -1 The reaction time is between 1 hour and 144 hours.

[0036] In one specific embodiment, the hydrogen gas flow rate and the adiponitrile mass hourly space velocity are proportional, specifically, the molar ratio of hydrogen to adiponitrile in the feed is between 5 and 200.

[0037] In one specific embodiment, the mass hourly space velocity (MSV) of the adiponitrile in the reaction is the ratio of the adiponitrile feed mass flow rate to the total mass of the supported nickel-based catalyst before reduction.

[0038] In one specific embodiment, the mass fraction of adiponitrile in the mixed solution of adiponitrile and solvent is between 5% and 50%, and the solvent is at least one of ethanol, methanol, and isopropanol.

[0039] The above-described technical solution of the present invention has the following advantages and beneficial effects:

[0040] The supported nickel-based catalyst prepared by the method provided in this invention has the following advantages: the supported nickel-based catalyst with excellent catalytic performance, long catalytic lifetime, good thermal stability and high mechanical strength can be obtained through a simple and low-cost preparation process, which has extremely high industrial application value and prospects.

[0041] The supported nickel-based catalyst provided by this invention is suitable for factories and enterprises that use adiponitrile and hydrogen as raw materials to produce hexamethylenediamine.

[0042] The supported nickel-based catalyst of the present invention can be applied to the hydrogenation of adiponitrile to hexamethylenediamine. The supported nickel-based catalyst exhibits good catalytic performance under mild conditions and avoids the addition of a large amount of strong base additives in the production process, thereby minimizing the investment cost of equipment, reducing energy consumption in the production process, and reducing potential environmental pollution.

[0043] The supported nickel-based catalyst of this invention is suitable for fixed-bed reactors and can effectively promote the large-scale continuous production capacity of hexamethylenediamine, alleviating the problem of insufficient supply of downstream products using hexamethylenediamine as a raw material in my country.

[0044] The supported nickel-based catalyst of this invention is prepared by an equal-volume impregnation method and modified with a metal modifier, which promotes the dispersion of the active components in the catalyst and provides basic sites conducive to the formation of primary amines. Under the same reaction conditions, it improves the conversion rate of adiponitrile and the selectivity of hexamethylenediamine compared with the unmodified catalyst. This invention avoids the addition of a large amount of strong base promoters with environmental pollution risks during the reaction process, and the catalyst itself has good thermal stability and mechanical strength, effectively solving the process technology problems of flammable catalysts, environmental pollution from strong base promoters, and high selectivity of by-products in existing processes. In the supported nickel-based catalyst described in this invention, the conversion rate of adiponitrile can be maintained at 100.00%, and the selectivity of hexamethylenediamine can reach over 82.07%. Attached Figure Description

[0045] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0046] Figure 1 This is a schematic diagram illustrating the catalytic performance of a supported nickel-based catalyst modified with different amounts of sodium metal modifiers for the hydrogenation of adiponitrile to hexamethylenediamine.

[0047] Figure 2 This is a schematic diagram illustrating the catalytic performance of a supported nickel-based catalyst modified with ZSM-5 molecular sieve using different amounts of sodium metal modifiers for the hydrogenation of adiponitrile to hexamethylenediamine. Detailed Implementation

[0048] The present invention will be further described below through preferred embodiments. Those skilled in the art should understand that the specific descriptions below are illustrative rather than restrictive, and the scope of protection of the present invention should not be limited thereto.

[0049] The reagents used in the embodiments of the present invention are shown in Table 1.

[0050] Table 1. Reagents used in the embodiments of the present invention.

[0051]

[0052]

[0053] Example 1:

[0054] The preparation process of the first catalyst, a nickel-based catalyst supported on γ-Al₂O₃, is as follows:

[0055] Based on the water absorption capacity of the γ-Al₂O₃ support (1.10 mL water / g support) and the water of crystallization content in the nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 0.55 g of sodium nitrate were added to 1.24 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.8 g of the γ-Al₂O₃ support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, the mixture was allowed to stand for 6 hours, dried at 110°C for 10 hours, and then calcined at 550°C for 5 hours to obtain the first catalyst of the nickel-based catalyst supported on γ-Al₂O₃.

[0056] The pore volume of the first catalyst is 0.25 cm³. 3 / g, with a specific surface area of ​​84.91m². 2 / g, with an average pore size of 7.32nm.

[0057] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 70%; the mass percentage of the active metal is 25%; and the mass percentage of the metal modifier is 5%.

[0058] Determination of the structure of the first catalyst: The size and morphology of the prepared first catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0059] II. Evaluation of the catalytic performance of the first catalyst:

[0060] The performance evaluation of the first catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen and nitrogen flow rates were both 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature, nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (MHV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile in the feed was 20, and the reaction results are shown in Table 2.

[0061] Example 2:

[0062] The preparation process of the second catalyst, which is a nickel-based catalyst supported on γ-Al2O3, is as follows:

[0063] Based on the water absorption capacity of 1.10 mL water / g support of the γ-Al2O3 support and the water of crystallization content in the nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 1.10 g of sodium nitrate were added to 1.02 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.6 g of the γ-Al2O3 support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, the mixture was allowed to stand for 6 hours and dried at 110 °C for 10 hours. Then, the dried impregnated material was calcined at 550 °C for 5 hours to obtain the second catalyst of the nickel-based catalyst supported on γ-Al2O3.

[0064] The pore volume of the second catalyst is 0.20 cm³. 3 / g, with a specific surface area of ​​47.63m². 2 / g, with an average pore size of 10.29nm.

[0065] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 65%; the mass percentage of the active metal is 25%; and the mass percentage of the metal modifier is 10%.

[0066] Determination of the structure of the second catalyst: The size and morphology of the prepared second catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0067] II. Evaluation of the catalytic performance of the second catalyst:

[0068] The performance evaluation of the second catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen and nitrogen flow rates were both 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. Nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0069] Example 3:

[0070] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0071] Weigh out 20.83 g of tetraethyl orthosilicate, 0.82 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 20:1:6:2:400. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Transfer the suspension to a hydrothermal crystallization vessel, seal the hydrothermal crystallization vessel, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0072] II. The preparation process of the third catalyst for the supported nickel-based catalyst with ZSM-5 molecular sieve as the support is as follows:

[0073] Based on the unit water absorption capacity of 1.39 mL water / g carrier of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed, and 4.95 g of nickel nitrate hexahydrate was added to 2.33 g of deionized water. The solution was prepared by heating and stirring in a constant temperature water bath until completely dissolved. 3 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, the solution was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the third catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0074] The pore volume of the third catalyst is 0.18 cm³. 3 / g, with a specific surface area of ​​193.78m². 2 / g, with an average pore size of 3.49nm.

[0075] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 75%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 0%; and the silicon-to-aluminum ratio of the support is 25.

[0076] The structure of the third catalyst was determined: the size and morphology of the prepared third catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0077] III. Evaluation of the catalytic performance of the third catalyst:

[0078] The performance evaluation of the third catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen and nitrogen flow rates were both 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. Nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0079] Example 4:

[0080] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0081] Weigh out 20.83 g of tetraethyl orthosilicate, 0.20 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 100:1:30:10:2000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Transfer the suspension to a hydrothermal crystallization vessel, seal the hydrothermal crystallization vessel, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0082] II. The preparation process of the fourth catalyst, which is a nickel-based catalyst supported on ZSM-5 molecular sieve, is as follows:

[0083] Based on the unit water absorption capacity of 1.42 mL water / g carrier of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed, and 4.95 g of nickel nitrate hexahydrate was added to 2.42 g of deionized water. The solution was prepared by heating and stirring in a constant temperature water bath until completely dissolved. 3 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, the solution was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the fourth catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0084] The pore volume of the fourth catalyst is 0.17 cm³. 3 / g, with a specific surface area of ​​203.07m². 2 / g, with an average pore size of 3.45nm.

[0085] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 75%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 0%; and the silicon-to-aluminum ratio of the support is 100.

[0086] Determination of the structure of the fourth catalyst: The size and morphology of the prepared fourth catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0087] III. Evaluation of the catalytic performance of the fourth catalyst:

[0088] The performance evaluation of the fourth catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen flow rate was 30mL / min, and the nitrogen flow rate was 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. The nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0089] Example 5:

[0090] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0091] Weigh out 20.83 g of tetraethyl orthosilicate, 0.41 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 50:1:15:5:1000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Then, transfer the suspension to a hydrothermal crystallization kettle, seal the hydrothermal crystallization kettle, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0092] II. The preparation process of the fifth catalyst, which is a nickel-based catalyst supported on ZSM-5 molecular sieve, is as follows:

[0093] Based on the unit water absorption capacity of 1.45 mL water / g carrier of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 0.55 g of sodium nitrate were added to 2.22 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.8 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, it was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the fifth catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0094] The pore volume of the fifth catalyst is 0.14 cm³. 3 / g, with a specific surface area of ​​105.72m². 2 / g, with an average pore size of 5.29nm.

[0095] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 70%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 5%; and the silicon-to-aluminum ratio of the support is 50.

[0096] Determination of the structure of the fifth catalyst: The size and morphology of the prepared fifth catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0097] III. Evaluation of the catalytic performance of the fifth catalyst:

[0098] The performance evaluation of the fifth catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen and nitrogen flow rates were both 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. Nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0099] Example 6:

[0100] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0101] Weigh out 20.83 g of tetraethyl orthosilicate, 0.41 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 50:1:15:5:1000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Then, transfer the suspension to a hydrothermal crystallization kettle, seal the hydrothermal crystallization kettle, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0102] II. The preparation process of the sixth catalyst, which is a nickel-based catalyst supported on ZSM-5 molecular sieve, is as follows:

[0103] Based on the unit water absorption capacity of 1.45 mL water / g carrier of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 1.10 g of sodium nitrate hexahydrate were added to 1.93 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.6 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, it was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the sixth catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0104] The pore volume of the sixth catalyst is 0.05 cm³. 3 / g, with a specific surface area of ​​20.99m². 2 / g, with an average pore size of 9.93nm.

[0105] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 65%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 10%; and the silicon-to-aluminum ratio of the support is 50.

[0106] Determination of the structure of the sixth catalyst: The size and morphology of the prepared sixth catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0107] III. Evaluation of the catalytic performance of the sixth catalyst:

[0108] The performance evaluation of the sixth catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen and nitrogen flow rates were both 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. Nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0109] Example 7:

[0110] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0111] Weigh out 20.83 g of tetraethyl orthosilicate, 0.41 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 50:1:15:5:1000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Then, transfer the suspension to a hydrothermal crystallization kettle, seal the hydrothermal crystallization kettle, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0112] II. The preparation process of the seventh catalyst, a nickel-based catalyst supported on ZSM-5 molecular sieve, is as follows:

[0113] Based on the unit water absorption capacity of 1.45 mL water / g support of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 0.50 g of cerium nitrate hexahydrate were added to 2.09 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.8 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, it was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the seventh catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0114] The pore volume of the seventh catalyst is 0.15 cm³. 3 / g, with a specific surface area of ​​155.72m². 2 / g, with an average pore size of 4.29nm.

[0115] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 70%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 5%; and the silicon-to-aluminum ratio of the support is 50.

[0116] Determination of the structure of the seventh catalyst: The size and morphology of the prepared seventh catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0117] III. Evaluation of the catalytic performance of the seventh catalyst:

[0118] The performance evaluation of the seventh catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen flow rate was 30mL / min, and the nitrogen flow rate was 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. The nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0119] Example 8:

[0120] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0121] Weigh out 20.83 g of tetraethyl orthosilicate, 0.41 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 50:1:15:5:1000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Then, transfer the suspension to a hydrothermal crystallization kettle, seal the hydrothermal crystallization kettle, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0122] II. The preparation process of the eighth catalyst, which is a nickel-based catalyst supported on ZSM-5 molecular sieve, is as follows:

[0123] Based on the unit water absorption capacity of 1.45 mL water / g carrier of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 1.27 g of magnesium nitrate hexahydrate were added to 1.68 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.8 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, it was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the eighth catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0124] The pore volume of the eighth catalyst is 0.16 cm³. 3 / g, with a specific surface area of ​​173.35m². 2 / g, with an average pore size of 3.98nm.

[0125] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 70%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 5%; and the silicon-to-aluminum ratio of the support is 50.

[0126] Determination of the structure of the eighth catalyst: The size and morphology of the prepared eighth catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0127] III. Evaluation of the catalytic performance of the eighth catalyst:

[0128] The performance evaluation of the eighth catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen flow rate was 30mL / min, and the nitrogen flow rate was 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. The nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0129] Example 9:

[0130] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0131] Weigh out 20.83 g of tetraethyl orthosilicate, 0.41 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 50:1:15:5:1000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Then, transfer the suspension to a hydrothermal crystallization kettle, seal the hydrothermal crystallization kettle, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0132] II. The preparation process of the ninth catalyst, a nickel-based catalyst supported on ZSM-5 molecular sieve, is as follows:

[0133] Based on the unit water absorption capacity of 1.45 mL water / g carrier of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 0.76 g of copper nitrate trihydrate were added to 2.05 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.8 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, it was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the ninth catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0134] The pore volume of the ninth catalyst is 0.14 cm³. 3 / g, with a specific surface area of ​​126.75m². 2 / g, with an average pore size of 4.93nm.

[0135] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 70%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 5%; and the silicon-to-aluminum ratio of the support is 50.

[0136] Determination of the structure of the ninth catalyst: The size and morphology of the prepared ninth catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0137] III. Evaluation of the catalytic performance of the ninth catalyst:

[0138] The performance evaluation of the ninth catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen flow rate was 30mL / min, and the nitrogen flow rate was 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. The nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow rate of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0139] Example 10:

[0140] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0141] Weigh out 20.83 g of tetraethyl orthosilicate, 0.41 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 50:1:15:5:1000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Then, transfer the suspension to a hydrothermal crystallization kettle, seal the hydrothermal crystallization kettle, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0142] II. The preparation process of the tenth catalyst, a supported nickel-based catalyst with ZSM-5 molecular sieve as the support, is as follows:

[0143] Based on the unit water absorption capacity of 1.45 mL water / g carrier of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 0.84 g of calcium nitrate tetrahydrate were added to 1.96 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.8 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, it was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the tenth catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0144] The pore volume of the tenth catalyst is 0.14 cm³. 3 / g, with a specific surface area of ​​110.28m². 2 / g, with an average pore size of 5.07nm.

[0145] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 70%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 5%; and the silicon-to-aluminum ratio of the support is 50.

[0146] Determination of the structure of the tenth catalyst: The size and morphology of the prepared tenth catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0147] III. Evaluation of the catalytic performance of the tenth catalyst:

[0148] The performance evaluation of the tenth catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen and nitrogen flow rates were both 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. Nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0149] Example 11:

[0150] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0151] Weigh out 20.83 g of tetraethyl orthosilicate, 0.41 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 50:1:15:5:1000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Then, transfer the suspension to a hydrothermal crystallization kettle, seal the hydrothermal crystallization kettle, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0152] II. The preparation process of the eleventh catalyst, which is a supported nickel-based catalyst with ZSM-5 molecular sieve as the support, is as follows:

[0153] Based on the unit water absorption capacity of 1.45 mL water / g carrier of ZSM-5 molecular sieve support and the crystal water content in nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate and 0.73 g of zinc nitrate hexahydrate were added to 1.95 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 2.8 g of ZSM-5 molecular sieve support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, it was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the eleventh catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve support.

[0154] The pore volume of the eleventh catalyst is 0.13 cm³. 3 / g, with a specific surface area of ​​93.37m². 2 / g, with an average pore size of 5.38nm.

[0155] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 70%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 5%; and the silicon-to-aluminum ratio of the support is 50.

[0156] Determination of the structure of the eleventh catalyst: The size and morphology of the prepared eleventh catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0157] III. Evaluation of the catalytic performance of the eleventh catalyst:

[0158] The performance evaluation of the eleventh catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen and nitrogen flow rates were both 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. Nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0159] Comparative Example 1:

[0160] The preparation process of the twelfth catalyst, a nickel-based catalyst supported on γ-Al₂O₃, is as follows:

[0161] Based on the unit water absorption of 1.10 mL water / g support of γ-Al2O3 and the water of crystallization content in nitrate, the required amount of deionized water was weighed. 4.95 g of nickel nitrate hexahydrate was added to 1.45 g of deionized water and heated and stirred in a constant temperature water bath until completely dissolved to prepare a salt solution. 3 g of γ-Al2O3 support was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, it was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the twelfth catalyst of the nickel-based catalyst supported on γ-Al2O3.

[0162] The pore volume of the twelfth catalyst is 0.32 cm³. 3 / g, with a specific surface area of ​​136.63m². 2 / g, with an average pore size of 6.13nm.

[0163] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 70%; the mass percentage of the active metal is 25%; and the mass percentage of the metal modifier is 5%.

[0164] Determination of the structure of the twelfth catalyst: The size and morphology of the prepared twelfth catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0165] II. Evaluation of the 12th Catalytic Performance:

[0166] The performance evaluation of the twelfth catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen flow rate was 30mL / min, and the nitrogen flow rate was 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. The nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0167] Comparative Example 2:

[0168] I. Synthesis of ZSM-5 molecular sieve support using dynamic hydrothermal method

[0169] Weigh out 20.83 g of tetraethyl orthosilicate, 0.41 g of aluminum isopropoxide, 15.25 g of tetrapropylammonium hydroxide, 0.40 g of sodium hydroxide, and 26.89 g of deionized water in a molar ratio of 50:1:15:5:1000. After weighing, add sodium hydroxide to deionized water and stir until completely dissolved. Then, add tetrapropylammonium hydroxide dropwise and stir continuously at room temperature for 1 hour to form a mixed solution. Add aluminum isopropoxide to the mixed solution and stir continuously for 3 hours until the aluminum isopropoxide is completely dissolved. Then, add tetraethyl orthosilicate dropwise and stir continuously for 15 hours to prepare a suspension and disperse it fully. Then, transfer the suspension to a hydrothermal crystallization kettle, seal the hydrothermal crystallization kettle, and crystallize the suspension at 170°C and a rotation speed of 90 r / min for 48 hours. After centrifugation and washing, the crystallized product was dried at 110°C for 12 hours. Finally, the dried product was calcined at 550°C for 5 hours and then ground and sieved to 20 to 40 mesh to obtain the carrier ZSM-5 molecular sieve.

[0170] II. The preparation process of the thirteenth catalyst, which is a nickel-based catalyst supported on ZSM-5 molecular sieve, is as follows:

[0171] Based on the unit water absorption capacity of 1.45 mL water / g carrier of ZSM-5 molecular sieve and the crystal water content in nitrate, the required amount of deionized water was weighed, and 4.95 g of nickel nitrate hexahydrate was added to 2.51 g of deionized water. The solution was prepared by heating and stirring in a constant temperature water bath until completely dissolved. 3 g of ZSM-5 molecular sieve carrier was added to the salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 1 hour. After impregnation, the solution was allowed to stand for 6 hours and dried at 110℃ for 10 hours. Then, the dried impregnated material was calcined at 550℃ for 5 hours to obtain the thirteenth catalyst of the nickel-based catalyst supported on ZSM-5 molecular sieve.

[0172] The pore volume of the thirteenth catalyst is 0.17 cm³. 3 / g, with a specific surface area of ​​200.765m². 2 / g, with an average pore size of 3.43nm.

[0173] In the supported nickel-based catalyst or the metal-modified supported nickel-based catalyst, the mass percentage of the support is 75%; the mass percentage of the active metal is 25%; the mass percentage of the metal modifier is 0%; and the silicon-to-aluminum ratio of the support is 50.

[0174] The structure of the thirteenth catalyst was determined: the size and morphology of the prepared twelfth catalyst were determined by scanning electron microscopy and transmission electron microscopy.

[0175] III. Evaluation of the catalytic performance of the thirteenth catalyst:

[0176] The performance evaluation of the thirteenth catalyst was conducted in a fixed-bed tubular reactor. 3g of supported nickel-based catalyst was placed in the isothermal section of the reaction tube. The temperature was then increased from room temperature to the reduction temperature at a rate of 2℃ / min in a mixed gas flow of hydrogen and nitrogen, and reduction was initiated. The hydrogen and nitrogen flow rates were both 30mL / min. The reduction conditions were: reduction at 400℃ and atmospheric pressure for 6 hours. After reduction, the temperature inside the fixed-bed tubular reactor was adjusted to the required reaction temperature. Nitrogen flow was stopped, and the pipeline was flushed with a pure hydrogen flow of 200mL / min for 10 minutes. After flushing, the pressure was increased with hydrogen to the required reaction pressure, and the hydrogen flow rate was set. A mixed solution of adiponitrile (20% by mass) and ethanol was introduced to initiate the reaction. Reaction conditions: reaction temperature 120℃, reaction pressure 4MPa, adiponitrile mass hourly space velocity (HHSV) 0.25h⁻¹. -1 The reaction time was 12 hours, the molar ratio of hydrogen to adiponitrile feed was 20, and the reaction results are shown in Table 2.

[0177] Table 2 Performance evaluation of catalysts 1 through 13

[0178]

[0179]

[0180] In Table 2, ADN conv. represents the conversion of adiponitrile, HMDA sel. represents the selectivity of hexamethylenediamine in the product, ACN sel. represents the selectivity of 6-aminohexanenitrile in the product, ACH sel. represents the selectivity of cycloheximine in the product, and other sel. represents the selectivity of other substances in the product.

[0181] As shown in Table 2, the supported nickel-based catalyst with γ-Al₂O₃ and ZSM-5 molecular sieve prepared by this invention, after modification with a suitable metal modifier, achieves highly efficient hydrogenation of adiponitrile to hexamethylenediamine. By changing the content of the metal additive, the product distribution can be adjusted, thereby improving the selectivity of hexamethylenediamine and reducing the selectivity of by-products while maintaining the conversion rate of adiponitrile. Figure 1 and Figure 2These are schematic diagrams illustrating the catalytic performance of supported nickel-based catalysts modified with different amounts of sodium metal modifiers on γ-Al₂O₃ supports and supported nickel-based catalysts modified with different amounts of sodium metal modifiers on ZSM-5 molecular sieves for the hydrogenation of adiponitrile to hexamethylenediamine. Compared to the supported nickel-based catalyst on γ-Al₂O₃ in Comparative Example 1, the supported nickel-based catalyst on γ-Al₂O₃ prepared in this invention exhibits higher adiponitrile conversion and hexamethylenediamine selectivity after modification with appropriate amounts of metal modifiers, and the selectivity of byproducts is significantly reduced. On the other hand, compared to the supported nickel-based catalyst on ZSM-5 molecular sieves in Comparative Example 2, the supported nickel-based catalyst on ZSM-5 molecular sieves prepared in this invention shows varying degrees of improvement or decrease in catalytic performance after modification with different metal modifiers, with the catalyst modified with sodium metal modifiers exhibiting higher hexamethylenediamine selectivity. During the reaction, the conversion rate of adiponitrile can reach 100%, the selectivity of hexamethylenediamine can reach 82.07%, and the selectivity of the byproduct cycloheximine can be controlled within 12%. Furthermore, the product does not contain the unhydrogenated intermediate 6-aminohexanonitrile. Therefore, the metal-modified nickel-based catalyst with γ-Al₂O₃ and ZSM-5 molecular sieves prepared in this invention exhibits superior catalytic performance compared to traditional supported nickel-based catalysts.

[0182] The above descriptions are merely some representative preferred examples and do not constitute any limitation on the present invention. The above-described examples of representative examples do not constitute any limitation on the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent implementation examples without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. The application of a supported nickel-based catalyst in the hydrogenation of adiponitrile to hexamethylenediamine, characterized in that: The preparation method of the supported nickel-based catalyst includes the following steps: Based on the unit water absorption of the carrier and the water of crystallization content in the nitrate, the required amount of deionized water is weighed, nickel nitrate is added to the deionized water, and heated and stirred until completely dissolved to prepare a salt solution; wherein the carrier includes γ-Al2O3 or ZSM-5 molecular sieve. The carrier is added to a salt solution and transferred to an ultrasonic machine for ultrasonic impregnation for 0.5 to 5 hours. After impregnation, it is left to stand for 4 to 20 hours to obtain the impregnated material. The impregnated material is dried for 3 to 24 hours at a temperature between 70°C and 130°C to obtain a dried impregnated material. The dried impregnated material was calcined for 2 to 12 hours at a temperature between 250°C and 650°C to obtain the supported nickel-based catalyst. The step of adding the nickel nitrate to the deionized water further includes: adding a metal modifier nitrate to the deionized water, wherein the metal modifier nitrate is sodium nitrate, and the mass of sodium oxide produced by the reaction is between 5% and 10% based on the total mass of the supported nickel-based catalyst. The application is performed through the following steps: The supported nickel-based catalyst was packed into the isothermal section of a fixed-bed tubular reactor. A mixed gas flow of hydrogen and nitrogen was introduced, and the supported nickel-based catalyst was heated from room temperature to the temperature required for reduction at a heating rate of 1°C / min to 10°C / min, and the reduction was then initiated. The temperature was then adjusted to the required reaction temperature. The nitrogen gas supply was stopped and the flushing pipeline was switched to a pure hydrogen gas flow. After flushing, the hydrogen gas was used to pressurize the pipeline and adjust it to the required reaction pressure. The flow rate of the hydrogen gas was set, and a mixed solution of adiponitrile and solvent in a certain proportion was introduced to start the reaction. After the reaction product was separated into gas and liquid phases, the liquid phase product was analyzed, and the catalytic performance of the supported nickel-based catalyst was evaluated based on the analysis results.

2. The application as described in claim 1, characterized in that: The reduction conditions are as follows: at atmospheric pressure, the reduction is carried out using a mixed gas flow of hydrogen and nitrogen; the reduction time is between 2 hours and 10 hours; the reduction temperature is between 300°C and 500°C; the flow rate of hydrogen is between 10 mL / min and 100 mL / min; the flow rate of nitrogen is between 10 mL / min and 100 mL / min; the flow rate of pure hydrogen gas in the flushing pipeline is between 10 mL / min and 200 mL / min; and the flushing time of the flushing pipeline is between 3 min and 30 min.

3. The application as described in claim 1, characterized in that: The reaction temperature is between 40°C and 180°C, the reaction pressure is between 0.5 MPa and 10 MPa, and the mass hourly space velocity (WHSV) of the adiponitrile is between 0.1 h⁻¹. -1 With 10h -1 The reaction time is between 1 hour and 144 hours; the molar ratio of hydrogen to adiponitrile feed is between 5 and 200; the mass hourly space velocity of the adiponitrile in the reaction is the ratio of the adiponitrile feed mass flow rate to the total mass of the supported nickel-based catalyst before reduction; and the mass fraction of adiponitrile in the mixed solution of adiponitrile and solvent is between 5% and 50%, and the solvent is at least one of ethanol, methanol, and isopropanol.

4. The application as described in claim 1, characterized in that: The nickel nitrate is nickel nitrate hexahydrate, and the mass of nickel in the supported nickel-based catalyst is between 5% and 50% based on the total mass of the catalyst.

5. The application as described in claim 1, characterized in that: In the step of heating and stirring until completely dissolved, the heating temperature is between 30°C and 110°C, and the heating time is between 3 min and 30 min.

6. The application as described in claim 1, characterized in that: Each gram of the carrier is γ-Al2O3 with a unit water absorption capacity of 0.3 mL to 4 mL of water, and each gram of the carrier is ZSM-5 molecular sieve with a unit water absorption capacity of 0.5 mL to 5 mL of water.

7. The application as described in claim 1, characterized in that: The ZSM-5 molecular sieve is prepared by the following steps: Tetraethyl orthosilicate, aluminum isopropoxide, tetrapropylammonium hydroxide, sodium hydroxide, and deionized water are weighed in sequence according to a molar ratio of 500:(1 to 50):150:50:10000. The sodium hydroxide is added to the deionized water and stirred until completely dissolved. Then, the tetrapropylammonium hydroxide is added dropwise and stirred continuously at room temperature for 0 to 2 hours to form a mixed solution. The aluminum isopropoxide is added to the mixed solution and stirred continuously for 2 to 4 hours until the aluminum isopropoxide is completely dissolved. Then, the tetraethyl orthosilicate is added dropwise and stirred continuously for 10 to 20 hours to prepare a suspension and disperse it fully. The suspension is transferred to a hydrothermal crystallization vessel, the vessel is sealed, and the suspension is liquidized for 12 to 72 hours at a temperature of 60°C to 220°C and a rotation speed of 30 r / min to 120 r / min to obtain a crystallized product. The crystallized product is washed by centrifugation and then dried at a temperature of 70°C to 130°C for 3 to 24 hours to obtain the dried crystallized product. as well as The dried crystallized product is calcined for 2 to 12 hours at 250°C to 650°C and then ground and sieved to 20 to 100 mesh to obtain the ZSM-5 molecular sieve.

8. The application as described in claim 1, characterized in that, The supported nickel-based catalyst comprises a support and an active metal, wherein the support comprises γ-Al₂O₃ or ZSM-5 molecular sieve; the active metal comprises nickel; the mass of the support is between 60% and 80% of the total mass of the supported nickel-based catalyst, and the mass of the active metal is between 15% and 40%; the supported nickel-based catalyst further comprises a metal modifier, wherein the metal modifier is an oxide of sodium; wherein the mass of the metal modifier is between 5% and 10% of the total mass of the supported nickel-based catalyst.

9. The application as described in claim 8, characterized in that: The supported nickel-based catalyst is in the shape of amorphous solid particles, and the size of the particles is between 150 μm and 850 μm.

10. The application as described in claim 8, characterized in that: The pore volume distribution of the supported nickel-based catalyst with γ-Al₂O₃ support ranges from 0.10 cm⁻¹. 3 / g and 0.50 cm 3 The specific surface area distribution ranges from / g to between 10m². 2 / g and 300 m 2 The average pore size distribution ranges between 3 nm and 15 nm; and the pore volume distribution of the supported nickel-based catalyst with ZSM-5 molecular sieve is between 0.05 cm³ / g. 3 / g and 0.30 cm 3 The specific surface area distribution ranges from / g to between 20 m² / g. 2 / g and 400 m 2 The average pore size distribution ranges from 2 nm to 11 nm, and the silicon-to-aluminum ratio is between 20 and 500.

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