Catalyst for the hydrogenation and amination of furfural to produce furfural amine and its preparation method

Abstract

This invention relates to the field of catalyst technology, specifically to a catalyst for the hydrogenation and amination of furfural to produce furfurylamine and its preparation method, comprising the following raw materials in parts by weight: 63-71 parts of support, 14-24 parts of additive, and 2-3 parts of additive; the catalyst for the hydrogenation and amination of furfural to produce furfurylamine is prepared by the following method: Step 1: Preparation of additive, the raw materials of which include porous materials, dopants, composite materials, and magnesium powder; Step 2: Preparation of support, the raw materials of which include γ-alumina, tetrabutyl titanate, and urea; Step 3: Support loading, to obtain a supported support; Step 4: Final preparation, to obtain the catalyst for the hydrogenation and amination of furfural to produce furfurylamine. This invention achieves high activity, high selectivity, and strong stability of the catalyst by precisely controlling the ruthenium-cobalt bimetallic ratio, the titanium-aluminum composite support structure, and the composite additive system.

Description

Technical Field

[0001] This invention relates to the field of catalyst technology, specifically to a catalyst for the hydrogenation and amination of furfural to produce furfural amine and its preparation method. Background Technology

[0002] Furfural is an important organic chemical intermediate with wide applications in pharmaceuticals, pesticides, dyes and other fields. The hydrogenation amination of furfural is an important process route for the preparation of furfural. The performance of the catalyst in this reaction directly affects the reaction efficiency, product selectivity and industrial production cost.

[0003] Current catalysts for the hydrogenation and amination of furfural to produce furfurylamine lack effective mechanisms for immobilizing active components. Traditional catalysts struggle to maintain high activity while ensuring stability over long periods, leading to rapid performance degradation and regeneration difficulties during continuous reactions. This fails to meet the stringent requirements of modern green chemical production for high efficiency and stability. Therefore, this invention provides a catalyst for the hydrogenation and amination of furfural to produce furfurylamine and its preparation method. Summary of the Invention

[0004] The purpose of this invention is to provide a catalyst for the hydrogenation and amination of furfural to produce furfurylamine and its preparation method. The catalyst prepared by this invention solves the problems of uneven dispersion of active components, high energy consumption at high temperatures, susceptibility to ammonia poisoning, and poor stability of traditional catalysts, and can effectively meet the stringent requirements of green chemical production for high efficiency and stability of catalysts.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing a catalyst for the hydrogenation and amination of furfural to produce furfural amine, comprising the following raw materials in parts by weight: 63-71 parts of support, 14-24 parts of auxiliaries, and 2-3 parts of additives;

[0006] The catalyst for the hydrogenation amination of furfural to produce furfural amine was prepared by the following method:

[0007] Step 1: Preparation of additives. The raw materials for additives include porous materials, dopants, composite materials, and magnesium powder.

[0008] Step 2: Carrier preparation. The raw materials for the carrier include γ-alumina, tetrabutyl titanate, and urea.

[0009] Step 3: Loading the carrier to obtain the load carrier;

[0010] Step 4: Final preparation, to obtain the catalyst for the hydrogenation and amination of furfural to produce furfural amine.

[0011] Preferably, the additive is selected from guar gum powder.

[0012] Preferably, the preparation method of the additive includes the following steps: weigh the porous material, dopant, and composite material as needed and add them to a mixer. Set the speed to 20-30 rpm and mix for 50-60 min. Then add magnesium powder and continue mixing for 30 min to obtain a premix. Add the premix to an atmosphere furnace, introduce ammonia gas, and heat it to 930-980℃ at 4-5℃ / min and keep it at that temperature for 2-3 h. After the product is crushed and ground, it is passed through a 100-150 mesh sieve to obtain the additive. The mass ratio of the porous material, dopant, composite material, and magnesium powder is (4-6):(2-4):(1-3):(0.5-1).

[0013] Preferably, the porous material is prepared by adding nano-silica and urea to a ball mill at a mass ratio of 1:3, setting the rotation speed to 350-450 rpm, and milling for 50-60 min. Then, the mixture is transferred to a tube furnace, nitrogen is introduced, and the temperature is raised to 650-750°C at a rate of 5°C / min and held for 100-120 min. The resulting product is crushed and passed through a 200-mesh sieve to obtain the porous material. The nitrogen flow rate is 50 ml / min.

[0014] Preferably, the preparation method of the dopant is as follows: sucrose and urea are dissolved in deionized water at a mass ratio of 2:3. The resulting product is added to a high-pressure reactor, the rotation speed is set to 250-300 rpm, the temperature is raised to 175-180℃, and the reaction is carried out for 2-3 hours. The resulting product is filtered to obtain a filter cake. The filter cake is added to a tube furnace and heated to 780-820℃ at 8-10℃ / min under a nitrogen atmosphere. The mixture is calcined for 180-200 minutes. The resulting product is ball-milled and passed through a 300-350 mesh sieve to obtain the dopant. The mass of sucrose is 12-14% of the mass of deionized water.

[0015] Preferably, the preparation method of the composite material is as follows: lanthanum nitrate and cerium nitrate are mixed at a mass ratio of 1:1 and added to deionized water. The mixture is stirred in a water bath at 60-65℃ until completely dissolved. Citric acid is then added, and stirring continues until a clear state is obtained, resulting in a mixed solution. The mixed solution is transferred to a constant temperature magnetic stirrer, and the temperature is set at 78-82℃ and the speed at 450-550 rpm. The mixture is stirred until the viscosity reaches 900-1100 Pa·s, resulting in a gel. The gel is then transferred to a muffle furnace and heated to 600℃ at a rate of 3-4℃ / min, and held for 120-150 min. The resulting product is pulverized to a particle size of 5-10 μm, which is the composite material. The mass of lanthanum nitrate is 9-11% of the mass of deionized water, and the mass ratio of lanthanum nitrate to citric acid is 1:(2-3).

[0016] Preferably, the specific method for preparing the carrier is as follows: γ-alumina, tetrabutyl titanate, and urea are added to a reaction vessel, ammonia is added dropwise to adjust the pH to 8.3-8.7, the rotation speed is set to 180-220 rpm and the temperature to 78-82℃, and the treatment is carried out for 100-130 min. The resulting product is transferred to a rotary kiln and calcined at 590-610℃ for 200-250 min to obtain the first coarse material. The first coarse material is then ground in a ball mill to a specific surface area of ​​220-240 m² / g to obtain the carrier.

[0017] Preferably, the mass ratio of γ-alumina, tetrabutyl titanate, and urea is (48-52):(4-6):(8-10).

[0018] Preferably, the carrier loading method includes the following steps;

[0019] Step 1: Mix ruthenium trichloride and cobalt nitrate at a molar ratio of 1.8:1, add deionized water, stir to dissolve, and obtain the impregnation solution. The total mass of ruthenium trichloride and cobalt nitrate is 2.5-3.5% of the carrier mass, and the solid content of the impregnation solution is 20-25%.

[0020] Step 2: Add the carrier to the impregnation tank, pour in the impregnation solution, and sonicate at 40 kHz for 50-60 min. Transfer the obtained product to an oven and dry at 105-115℃ for 200-240 min to obtain the loaded carrier.

[0021] Preferably, the specific method for the final preparation includes the following steps:

[0022] S1: Add the additives, support carrier, and additives to the mixer, set the speed to 40-50 rpm, and mix for 40-50 minutes to obtain the mixture.

[0023] S2: Add the mixture to a tablet press and produce granules with a particle size of 5-6 mm under a pressure of 15 MPa;

[0024] S3: The granular material is loaded into a fixed-bed reactor, and after hydrogen is introduced, the temperature is increased to 350-400℃ at a heating rate of 2-3℃ / min, and then held at a constant temperature for 175-185min. The resulting product is cooled to room temperature under nitrogen protection to obtain the furfural hydrogenation amination catalyst for furfural amine production.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] This invention discloses a method for preparing a catalyst for the hydrogenation and amination of furfural to produce furfural amine. By precisely controlling the ruthenium-cobalt bimetallic ratio, the titanium-aluminum composite support structure, and the composite additive system, the catalyst achieves high activity, high selectivity, and strong stability. Through the synergistic effect of specific ratios of active components, the mass transfer advantages of a hierarchical porous support, and the construction of a nitrogen-resistant environment, it solves the problems of uneven dispersion of active components, high energy consumption at high temperatures, susceptibility to ammonia poisoning, and poor stability of traditional catalysts. It is suitable for green synthesis processes in the field of biomass conversion and also provides an efficient, stable, and environmentally friendly catalytic solution for the amination reactions of other aldehyde-containing compounds, promoting energy conservation and sustainable development in related chemical production. Attached Figure Description

[0027] Figure 1 A flowchart is provided for the invention of a catalyst for the hydrogenation and amination of furfural to produce furfural amine and its preparation method. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0030] Example 1

[0031] A method for preparing a catalyst for the hydrogenation and amination of furfural to produce furfural amine includes the following raw materials in parts by weight: 63 parts of support, 14 parts of auxiliary agent, and 2 parts of additive;

[0032] The catalyst for the hydrogenation amination of furfural to produce furfural amine was prepared by the following method:

[0033] Step 1: Preparation of additives. The raw materials for additives include porous materials, dopants, composite materials, and magnesium powder.

[0034] Step 2: Carrier preparation. The raw materials for the carrier include γ-alumina, tetrabutyl titanate, and urea.

[0035] Step 3: Loading the carrier to obtain the load carrier;

[0036] Step 4: Final preparation, to obtain the catalyst for the hydrogenation and amination of furfural to produce furfural amine.

[0037] The additive is selected from guar gum powder.

[0038] The preparation method of the additive includes the following steps: Weigh the porous material, dopant, and composite material as needed and add them to a mixer. Mix at 20 rpm for 50 min. Then add magnesium powder and continue mixing for 30 min to obtain a premix. Add the premix to an atmosphere furnace, introduce ammonia gas, and heat to 930℃ at 4℃ / min and keep warm for 2 h. The obtained product is pulverized and ground and then passed through a 100-mesh sieve to obtain the additive. The mass ratio of porous material, dopant, composite material, and magnesium powder is 4:2:1:0.5.

[0039] The porous material is prepared by adding nano-silica and urea to a ball mill at a mass ratio of 1:3, setting the speed to 350 rpm, and milling for 50 min. Then, the mixture is transferred to a tube furnace, nitrogen is introduced, and the temperature is raised to 650℃ at 5℃ / min and held for 100 min. The resulting product is crushed and passed through a 200-mesh sieve to obtain the porous material. The nitrogen flow rate is 50 ml / min.

[0040] The preparation method of the dopant is as follows: sucrose and urea are dissolved in deionized water at a mass ratio of 2:3. The resulting product is added to a high-pressure reactor, the rotation speed is set to 250 rpm, the temperature is raised to 175°C, and the reaction is carried out for 2 hours. The resulting product is filtered to obtain a filter cake. The filter cake is added to a tube furnace and heated to 780°C at 8°C / min under a nitrogen atmosphere. The mixture is then calcined for 180 minutes. The resulting product is ball-milled and passed through a 300-mesh sieve to obtain the dopant. The mass of sucrose is 12% of the mass of deionized water.

[0041] The preparation method of the composite material is as follows: lanthanum nitrate and cerium nitrate are mixed at a mass ratio of 1:1 and added to deionized water. The mixture is stirred in a 60°C water bath until completely dissolved. Citric acid is then added, and stirring continues until a clear state is obtained. The mixture is then transferred to a constant-temperature magnetic stirrer, set to a temperature of 78°C and a speed of 450 rpm, and stirred until the viscosity reaches 900 Pa·s to obtain a gel. This gel is then transferred to a muffle furnace and heated to 600°C at a rate of 3°C / min, and held for 120 min. The resulting product is pulverized to a particle size of 5 μm, which is the composite material. The mass of lanthanum nitrate is 9% of the mass of deionized water, and the mass ratio of lanthanum nitrate to citric acid is 1:2.

[0042] The specific method for preparing the carrier is as follows: γ-alumina, tetrabutyl titanate and urea are added to the reaction vessel, ammonia water is added dropwise to adjust the pH to 8.3, the rotation speed is set to 180 rpm and the temperature is 78℃, and the treatment is carried out for 100 min. The resulting product is transferred to a rotary kiln and calcined at 590℃ for 200 min to obtain the first coarse material. The first coarse material is ground by a ball mill to a specific surface area of ​​220 m² / g to obtain the carrier.

[0043] The mass ratio of γ-alumina, tetrabutyl titanate, and urea is 48:4:8.

[0044] The specific method for carrier loading includes the following steps;

[0045] Step 1: Mix ruthenium trichloride and cobalt nitrate in a molar ratio of 1.8:1, add deionized water, stir to dissolve, and obtain an impregnation solution. The total mass of ruthenium trichloride and cobalt nitrate is 2.5% of the carrier mass, and the solid content of the impregnation solution is 20%.

[0046] Step 2: Add the carrier to the impregnation tank, pour in the impregnation solution, and sonicate at 40 kHz for 50 min. Transfer the obtained product to an oven and dry at 105 ℃ for 200 min to obtain the loaded carrier.

[0047] The specific method for final preparation includes the following steps:

[0048] S1: Add the additives, support carrier, and additives to the mixer, set the speed to 40 rpm, and mix for 40 minutes to obtain the mixture;

[0049] S2: Add the mixture to the tablet press and produce granules with a particle size of 5mm under a pressure of 15MPa;

[0050] S3: The granular material is loaded into a fixed-bed reactor, hydrogen is introduced, and the temperature is increased to 350°C at a rate of 2°C / min. The temperature is then maintained for 175 min. The resulting product is cooled to room temperature under nitrogen protection to obtain the furfural hydrogenation amination catalyst for the production of furfural amine.

[0051] Example 2

[0052] A method for preparing a catalyst for the hydrogenation and amination of furfural to produce furfural amine includes the following raw materials in parts by weight: 67 parts of support, 19 parts of auxiliary agent, and 2.5 parts of additive;

[0053] The catalyst for the hydrogenation amination of furfural to produce furfural amine was prepared by the following method:

[0054] Step 1: Preparation of additives. The raw materials for additives include porous materials, dopants, composite materials, and magnesium powder.

[0055] Step 2: Carrier preparation. The raw materials for the carrier include γ-alumina, tetrabutyl titanate, and urea.

[0056] Step 3: Loading the carrier to obtain the load carrier;

[0057] Step 4: Final preparation, to obtain the catalyst for the hydrogenation and amination of furfural to produce furfural amine.

[0058] The additive is selected from guar gum powder.

[0059] The preparation method of the additive includes the following steps: Weigh the porous material, dopant, and composite material as needed and add them to a mixer. Mix at 25 rpm for 55 minutes. Then add magnesium powder and continue mixing for 30 minutes to obtain a premix. Add the premix to an atmosphere furnace, introduce ammonia gas, and heat to 950℃ at 4.5℃ / min and hold for 2.5 hours. The resulting product is pulverized and ground and then passed through a 125-mesh sieve to obtain the additive. The mass ratio of porous material, dopant, composite material, and magnesium powder is 5:3:2:0.8.

[0060] The porous material is prepared by adding nano-silica and urea to a ball mill at a mass ratio of 1:3, setting the speed to 400 rpm, and milling for 55 min. Then, the mixture is transferred to a tube furnace, nitrogen is introduced, and the temperature is raised to 700℃ at 5℃ / min and held for 110 min. The resulting product is crushed and passed through a 200-mesh sieve to obtain the porous material. The nitrogen flow rate is 50 ml / min.

[0061] The preparation method of the dopant is as follows: sucrose and urea are dissolved in deionized water at a mass ratio of 2:3. The resulting product is added to a high-pressure reactor, the rotation speed is set to 280 rpm, the temperature is raised to 178°C, and the reaction is carried out for 2.5 h. The resulting product is filtered to obtain a filter cake. The filter cake is added to a tube furnace and heated to 800°C at 9°C / min under a nitrogen atmosphere. The mixture is then calcined for 190 min. The resulting product is ball-milled and passed through a 320-mesh sieve to obtain the dopant. The mass of sucrose is 13% of the mass of deionized water.

[0062] The preparation method of the composite material is as follows: lanthanum nitrate and cerium nitrate are mixed at a mass ratio of 1:1 and added to deionized water. The mixture is stirred in a 63℃ water bath until completely dissolved. Citric acid is then added, and stirring continues until a clear state is obtained. The mixture is then transferred to a constant temperature magnetic stirrer, set to 80℃ and 500 rpm, and stirred until the viscosity reaches 1000 Pa·s to obtain a gel. This gel is then transferred to a muffle furnace and heated to 600℃ at a rate of 3.5℃ / min, and held for 135 min. The resulting product is pulverized to a particle size of 8 μm, which is the composite material. The mass of lanthanum nitrate is 10% of the mass of deionized water, and the mass ratio of lanthanum nitrate to citric acid is 1:2.5.

[0063] The specific method for preparing the carrier is as follows: γ-alumina, tetrabutyl titanate and urea are added to the reaction vessel, ammonia water is added dropwise to adjust the pH to 80.5, the rotation speed is set to 200 rpm and the temperature to 80℃, and the treatment is carried out for 115 min. The resulting product is transferred to a rotary kiln and calcined at 600℃ for 220 min to obtain the first coarse material. The first coarse material is ground by a ball mill to a specific surface area of ​​230 m² / g to obtain the carrier.

[0064] The mass ratio of γ-alumina, tetrabutyl titanate, and urea is 50:5:9.

[0065] The specific method for carrier loading includes the following steps;

[0066] Step 1: Mix ruthenium trichloride and cobalt nitrate in a molar ratio of 1.8:1, add deionized water, stir to dissolve, and obtain an impregnation solution. The total mass of ruthenium trichloride and cobalt nitrate is 3% of the carrier mass, and the solid content of the impregnation solution is 22%.

[0067] Step 2: Add the carrier to the impregnation tank, pour in the impregnation solution, and sonicate at 40 kHz for 55 min. Transfer the obtained product to an oven and dry at 108 ℃ for 220 min to obtain the loaded carrier.

[0068] The specific method for final preparation includes the following steps:

[0069] S1: Add the additives, support carrier, and additives to the mixer, set the speed to 45 rpm, and mix for 45 minutes to obtain the mixture;

[0070] S2: Add the mixture to the tablet press and produce granules with a particle size of 5.5 mm under a pressure of 15 MPa;

[0071] S3: The granular material is loaded into a fixed-bed reactor, hydrogen is introduced, and the temperature is increased to 380°C at a rate of 2.5°C / min. The temperature is then maintained for 180 min. The resulting product is cooled to room temperature under nitrogen protection to obtain the furfural hydrogenation amination catalyst for the production of furfural amine.

[0072] Example 3

[0073] A method for preparing a catalyst for the hydrogenation and amination of furfural to produce furfural amine includes the following raw materials in parts by weight: 71 parts of support, 24 parts of auxiliary agent, and 3 parts of additive;

[0074] The catalyst for the hydrogenation amination of furfural to produce furfural amine was prepared by the following method:

[0075] Step 1: Preparation of additives. The raw materials for additives include porous materials, dopants, composite materials, and magnesium powder.

[0076] Step 2: Carrier preparation. The raw materials for the carrier include γ-alumina, tetrabutyl titanate, and urea.

[0077] Step 3: Loading the carrier to obtain the load carrier;

[0078] Step 4: Final preparation, to obtain the catalyst for the hydrogenation and amination of furfural to produce furfural amine.

[0079] The additive is selected from guar gum powder.

[0080] The preparation method of the additive includes the following steps: Weigh the porous material, dopant, and composite material as needed and add them to a mixer. Mix at 30 rpm for 60 min. Then add magnesium powder and continue mixing for 30 min to obtain a premix. Add the premix to an atmosphere furnace, introduce ammonia gas, and heat to 980℃ at 5℃ / min and keep warm for 3 h. The obtained product is pulverized and ground and then passed through a 150-mesh sieve to obtain the additive. The mass ratio of porous material, dopant, composite material, and magnesium powder is 6:4:3:1.

[0081] The porous material is prepared by adding nano-silica and urea to a ball mill at a mass ratio of 1:3, setting the speed to 450 rpm, and milling for 60 min. Then, the mixture is transferred to a tube furnace, nitrogen is introduced, and the temperature is raised to 750℃ at a rate of 5℃ / min and held for 120 min. The resulting product is crushed and passed through a 200-mesh sieve to obtain the porous material. The nitrogen flow rate is 50 ml / min.

[0082] The preparation method of the dopant is as follows: sucrose and urea are dissolved in deionized water at a mass ratio of 2:3. The resulting product is added to a high-pressure reactor, the rotation speed is set to 300 rpm, the temperature is raised to 180℃, and the reaction is carried out for 3 hours. The resulting product is filtered to obtain a filter cake. The filter cake is added to a tube furnace and heated to 820℃ at 10℃ / min under a nitrogen atmosphere. The mixture is then calcined for 200 minutes. The resulting product is ball-milled and passed through a 350-mesh sieve to obtain the dopant. The mass of sucrose is 14% of the mass of deionized water.

[0083] The preparation method of the composite material is as follows: lanthanum nitrate and cerium nitrate are mixed at a mass ratio of 1:1 and added to deionized water. The mixture is stirred in a 65°C water bath until completely dissolved. Citric acid is then added, and stirring continues until a clear state is obtained. The mixture is then transferred to a constant-temperature magnetic stirrer, set to a temperature of 82°C and a speed of 550 rpm, and stirred until the viscosity reaches 1100 Pa·s to obtain a gel. This gel is then transferred to a muffle furnace and heated to 600°C at a rate of 4°C / min, and held for 150 min. The resulting product is pulverized to a particle size of 10 μm, which is the composite material. The mass of lanthanum nitrate is 11% of the mass of deionized water, and the mass ratio of lanthanum nitrate to citric acid is 1:3.

[0084] The specific method for preparing the carrier is as follows: γ-alumina, tetrabutyl titanate and urea are added to the reaction vessel, ammonia water is added dropwise to adjust the pH to 8.7, the rotation speed is set to 220 rpm and the temperature to 82℃, and the treatment is carried out for 130 min. The resulting product is transferred to a rotary kiln and calcined at 610℃ for 250 min to obtain the first coarse material. The first coarse material is ground by a ball mill to a specific surface area of ​​240 m² / g to obtain the carrier.

[0085] The mass ratio of γ-alumina, tetrabutyl titanate, and urea is 52:6:10.

[0086] The specific method for carrier loading includes the following steps;

[0087] Step 1: Mix ruthenium trichloride and cobalt nitrate in a molar ratio of 1.8:1, add deionized water, stir to dissolve, and obtain the impregnation solution. The total mass of ruthenium trichloride and cobalt nitrate is 3.5% of the carrier mass, and the solid content of the impregnation solution is 25%.

[0088] Step 2: Add the carrier to the impregnation tank, pour in the impregnation solution, and sonicate at 40 kHz for 60 min. Transfer the obtained product to an oven and dry at 115 ℃ for 240 min to obtain the loaded carrier.

[0089] The specific method for final preparation includes the following steps:

[0090] S1: Add the additives, support carrier, and additives to the mixer, set the speed to 50 rpm, and mix for 50 minutes to obtain the mixture;

[0091] S2: Add the mixture to the tablet press and produce granules with a particle size of 6mm under a pressure of 15MPa;

[0092] S3: The granular material is loaded into a fixed-bed reactor, hydrogen is introduced, and the temperature is increased to 400°C at a rate of 3°C / min. The temperature is then maintained for 185 min. The resulting product is cooled to room temperature under nitrogen protection to obtain the furfural hydrogenation amination catalyst for the production of furfural amine.

[0093] Comparative Example 1: The difference between this comparative example and Example 1 is that the additives do not contain composite materials.

[0094] Comparative Example 2 differs from Example 1 in that the molar ratio of ruthenium trichloride to cobalt nitrate is changed to 1:1 when the carrier is loaded.

[0095] Comparative Example 3 differs from Example 1 in that ultrasonic treatment is omitted when the carrier is loaded, and only mechanical stirring and impregnation are used.

[0096] Comparative Example 4 differs from Example 1 in that the carrier preparation does not contain tetrabutyl titanate.

[0097] Test method: A fixed-bed reactor was used with a catalyst loading of 5g; the reaction raw material was a furfural-ammonia mixture (furfural:ammonia molar ratio 1:3), and hydrogen was used as the reducing gas (furfural:hydrogen molar ratio 1:5); the reaction temperature was 150℃, the pressure was 2MPa, the liquid hourly space velocity was 1h⁻¹, and the reaction was carried out continuously for 6h. Based on this, the furfural conversion rate, furfuralamine selectivity, and stability were tested.

[0098] Furfural conversion rate: (Initial furfural amount - Unreacted furfural amount) / Initial furfural amount × 100%;

[0099] Furfurylamine selectivity: Amount of furfurylamine produced / Amount of furfural converted × 100%;

[0100] Stability: After 5 consecutive cycles, the conversion rate of the 5th reaction is multiplied by the conversion rate of the first reaction by 100%.

[0101] The test data for Examples 1-3 and Comparative Examples 1-4 are recorded in the table below:

[0102]

[0103] Comparative analysis of the data in the table shows that the furfural conversion rate, furfuralamine selectivity, and stability in Examples 1-3 are quite similar.

[0104] Comparative analysis of Comparative Example 1 and Examples 1-3 shows that in Comparative Example 1, the furfural conversion rate decreased by about 12%, the selectivity of furfuralamine decreased by about 12%, and the stability decreased by about 28%. This is because the lanthanum and cerium rare earth elements in the composite material can form oxygen vacancies, promote the adsorption and activation of reaction intermediates, and inhibit the formation of carbon deposits. Without the composite material, the number of active sites decreases, the carbon deposition rate accelerates, and the performance decreases significantly.

[0105] Comparative analysis of Example 2 and Examples 1-3 shows that the furfural conversion rate decreased by about 8% and the furfural selectivity decreased by about 7%. This is because the Ru-Co ratio of 1.8:1 can form the optimal synergistic effect (Ru activates hydrogen and Co promotes the breaking of C=N bonds). When the ratio is changed to 1:1, the bimetallic synergistic effect weakens and the matching degree of active sites decreases, resulting in a decrease in reaction efficiency.

[0106] Comparative analysis of Comparative Example 3 and Examples 1-3 shows that the furfural conversion rate decreased by about 6% and the furfural selectivity decreased by about 9%. This is because ultrasonic treatment promotes the penetration of active components into the carrier pores through the cavitation effect, thereby increasing the dispersion. The decrease in dispersion leads to the aggregation of active sites, a reduction in effective specific surface area, and an increase in side reactions (such as excessive hydrogenation of furfural to produce furfuryl alcohol).

[0107] Comparative analysis of Comparative Example 4 and Examples 1-3 shows that the performance of Comparative Example 4 is the most significantly reduced. This is because TiO formed by the hydrolysis of tetrabutyl titanate forms a composite support with γ-alumina, which can improve thermal stability and surface acidity uniformity. When only γ-alumina is used, the support is prone to phase transformation during high-temperature reaction, leading to pore collapse, sintering of active components, and a sharp decrease in stability.

[0108] Therefore, this catalyst exhibits superior low-temperature hydrogenation activity through precise control of the active component ratio and support structure. Its core lies in the synergistic effect of the 1.8:1 Ru-Co bimetallic ratio. Ru efficiently activates hydrogen, while Co promotes the selective breaking of C=N bonds. Combined with the high specific surface area (220-240 m² / g) and hierarchical pores (3-10 nm) of the titanium-aluminum composite support, the furfural hydrogenation amination reaction can proceed efficiently at lower temperatures. Compared to traditional catalysts that require high temperatures (above 200°C) to drive the reaction, this catalyst can achieve 96% furfural conversion and 92% hydrogenation efficiency at 150°C. The high selectivity of furfural-amine significantly reduces energy consumption. Simultaneously, the nitrogen-resistant environment created by the dopants and composites effectively mitigates the poisoning of active sites by ammonia, ensuring reaction stability. This characteristic is perfectly suited for green synthesis processes in biomass conversion, reducing side reactions and energy consumption caused by high temperatures, aligning with low-carbon and environmentally friendly principles, and providing a sustainable solution for the efficient conversion of biomass derivatives such as furfural. Furthermore, in this catalyst, dopants weaken ammonia adsorption by adjusting the electronic structure, the interconnected channels of the porous material accelerate ammonia diffusion, and the stable framework formed by magnesium powder nitridation inhibits the covering of active components by nitrogen species. After 5 cycles, the stability reaches 88%, far exceeding that of traditional catalysts. This nitrogen-resistant characteristic not only ensures the long-term stable operation of the furfural hydrogenation amination reaction but also lays the foundation for its expansion into the amination reactions of other aldehyde-containing compounds. For example, in the amination reactions of benzaldehyde and formaldehyde, it can effectively resist interference from nitrogen-containing species in the reaction system, maintaining high selectivity. In addition, the use of green additives such as guar gum powder in its preparation process further reduces the environmental impact, providing an efficient, stable, and environmentally friendly catalytic option for the amination reactions of aldehyde-containing compounds in multiple fields.

[0109] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0110] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing a catalyst for the hydrogenation and amination of furfural to produce furfurylamine, characterized in that, The raw materials include the following parts by weight: 63-71 parts carrier, 14-24 parts auxiliary agent, and 2-3 parts additive; The catalyst for the hydrogenation amination of furfural to produce furfural amine was prepared by the following method: Step 1: Preparation of additives. The raw materials for additives include porous materials, dopants, composite materials, and magnesium powder. Step 2: Carrier preparation. The raw materials for the carrier include γ-alumina, tetrabutyl titanate, and urea. Step 3: Carrier loading, to obtain the loaded carrier, specifically, ruthenium trichloride and cobalt nitrate are loaded onto the carrier in a molar ratio of 1.8:1; Step 4: Final preparation, to obtain the catalyst for the hydrogenation and amination of furfural to produce furfural-amine; The preparation method of the additive includes the following steps: Weigh the porous material, dopant, and composite material as needed and add them to a mixer. Set the speed to 20-30 rpm and mix for 50-60 minutes. Then add magnesium powder and continue mixing for 30 minutes to obtain a premix. Add the premix to an atmosphere furnace, introduce ammonia gas, and heat it to 930-980℃ at 4-5℃ / min and keep it at that temperature for 2-3 hours. After pulverizing and grinding the obtained product, pass it through a 100-150 mesh sieve to obtain the additive. The mass ratio of the porous material, dopant, composite material, and magnesium powder is (4-6):(2-4):(1-3):(0.5-1). The porous material is prepared as follows: nano-silica and urea are added to a ball mill at a mass ratio of 1:3, the speed is set to 350-450 rpm, the ball mill is milled for 50-60 min, and then transferred to a tube furnace. Nitrogen gas is introduced and the temperature is raised to 650-750℃ at 5℃ / min and held for 100-120 min. The obtained product is crushed and passed through a 200-mesh sieve to obtain the porous material. The nitrogen gas flow rate is 50 mL / min. The preparation method of the dopant is as follows: sucrose and urea are dissolved in deionized water at a mass ratio of 2:

3. The resulting product is added to a high-pressure reactor, the rotation speed is set to 250-300 rpm, the temperature is raised to 175-180℃, and the reaction is carried out for 2-3 hours. The resulting product is filtered to obtain a filter cake. The filter cake is added to a tube furnace and heated to 780-820℃ at 8-10℃ / min under a nitrogen atmosphere, and calcined for 180-200 minutes. The resulting product is ball-milled and passed through a 300-350 mesh sieve to obtain the dopant. The mass of sucrose is 12-14% of the mass of deionized water. The preparation method of the composite material is as follows: lanthanum nitrate and cerium nitrate are mixed at a mass ratio of 1:1 and added to deionized water. The mixture is stirred in a water bath at 60-65℃ until completely dissolved. Citric acid is then added, and stirring continues until a clear state is obtained, resulting in a mixed solution. The mixed solution is transferred to a constant temperature magnetic stirrer, and the temperature is set at 78-82℃ and the speed at 450-550 rpm. The mixture is stirred until the viscosity reaches 900-1100 Pa·s, resulting in a gel. The gel is then transferred to a muffle furnace and heated to 600℃ at a rate of 3-4℃ / min, and held for 120-150 min. The resulting product is pulverized to a particle size of 5-10 μm, which is the composite material. The mass of lanthanum nitrate is 9-11% of the mass of deionized water, and the mass ratio of lanthanum nitrate to citric acid is 1:(2-3).

2. In the preparation method of the furfural hydrogenation amination catalyst for producing furfural amine according to claim 1, the additive is selected from guar gum powder.

3. The method for preparing the catalyst for the hydrogenation and amination of furfural to produce furfurylamine according to claim 1, characterized in that, The specific method for preparing the carrier is as follows: γ-alumina, tetrabutyl titanate, and urea are added to a reaction vessel, and ammonia is added dropwise to adjust the pH to 8.3-8.

7. The rotation speed is set to 180-220 rpm and the temperature to 78-82℃, and the treatment is carried out for 100-130 min. The resulting product is transferred to a rotary kiln and calcined at 590-610℃ for 200-250 min to obtain the first coarse material. The first coarse material is then ground in a ball mill to a specific surface area of ​​220-240 m² / g to obtain the carrier.

4. The preparation method of the furfural hydrogenation amination catalyst for furfural-amine production according to claim 3, characterized in that, The mass ratio of γ-alumina, tetrabutyl titanate, and urea is (48-52):(4-6):(8-10).

5. The method for preparing the catalyst for the hydrogenation and amination of furfural to produce furfurylamine according to claim 1, characterized in that, The specific method for carrier loading includes the following steps; Step 1: Mix ruthenium trichloride and cobalt nitrate at a molar ratio of 1.8:1, add deionized water, stir to dissolve, and obtain the impregnation solution. The total mass of ruthenium trichloride and cobalt nitrate is 2.5-3.5% of the carrier mass, and the solid content of the impregnation solution is 20-25%. Step 2: Add the carrier to the impregnation tank, pour in the impregnation solution, and sonicate at 40 kHz for 50-60 min. Transfer the obtained product to an oven and dry at 105-115℃ for 200-240 min to obtain the loaded carrier.

6. The method for preparing the catalyst for the hydrogenation and amination of furfural to produce furfurylamine according to claim 1, characterized in that, The specific method for final preparation includes the following steps: S1: Add the additives, support carrier, and additives to the mixer, set the speed to 40-50 rpm, and mix for 40-50 minutes to obtain the mixture. S2: Add the mixture to a tablet press and produce granules with a particle size of 5-6 mm under a pressure of 15 MPa; S3: The granular material is loaded into a fixed-bed reactor, and after hydrogen is introduced, the temperature is increased to 350-400℃ at a heating rate of 2-3℃ / min, and then held at a constant temperature for 175-185min. The resulting product is cooled to room temperature under nitrogen protection to obtain the furfural hydrogenation amination catalyst for furfural amine production.

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