A process for the activation and regeneration of a deactivated copper catalyst and its application

Abstract

This invention relates to the field of catalyst regeneration technology, specifically to a process for the activation and regeneration of deactivated copper catalysts and its application. The process includes the following steps: S1. Washing and alkali treatment; S2. Cleaning; S3. Mixing and loading; S4. Functionalization with modified silica gel; S5. Activation and reduction. This invention, through a unique multi-step process, significantly improves catalyst regeneration efficiency and drastically shortens regeneration time compared to traditional methods. Simultaneously, it effectively reduces the amount of chemical reagents used during regeneration, lowering production costs. Copper catalysts regenerated using this method exhibit significantly enhanced activity and stability, significantly improving the efficiency of related chemical reactions and product quality, thus possessing extremely high industrial application value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalyst regeneration, in particular to an activation regeneration preparation process of deactivated copper catalyst and application thereof. BACKGROUND

[0002] Acrylamide is an important chemical raw material, widely used in water treatment, papermaking, textile and oil exploitation fields. Copper catalyst is a key catalyst in acrylamide production, and its activity and stability directly affect the production efficiency and product quality.

[0003] In the prior art, copper catalyst will gradually deactivate during use, resulting in decreased hydration catalytic efficiency. Traditional regeneration methods usually include washing, drying and activation steps, but have the following problems: the activity of the regenerated catalyst is not fully recovered, and the hydration catalytic efficiency is low; by-products are easily produced during the regeneration process, affecting the purity and stability of the catalyst; the process is complex, energy consumption is high, and production cost is high; the newly added catalyst is prone to violent exothermic reaction with liquid alkali due to the activity of the surface metal aluminum, which has certain safety hazards; the high-concentration wastewater produced after regeneration is not environmentally friendly.

[0004] Therefore, it is of great significance to develop an efficient and low-cost copper catalyst regeneration process. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present application is to provide an activation regeneration preparation process of deactivated copper catalyst and application thereof.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0007] An activation regeneration preparation process of deactivated copper catalyst, comprising the following steps:

[0008] S1. Washing and alkali treatment: washing the newly added copper catalyst with deionized water for 4-5 times, and then soaking in a sodium hydroxide solution with a mass concentration of 5-10% for 18-20h to obtain a pretreated catalyst;

[0009] S2. Cleaning: soaking the pretreated catalyst in deionized water at 60-70℃ for 18-20h to obtain a de-alkali treated catalyst;

[0010] S3. Mixed packing: mixing and uniformly the de-alkali treated catalyst with the deactivated copper catalyst, and sequentially packing into a three-stage reactor for cyclic regeneration operation;

[0011] S4. Modification of functional modification of modified silica gel: adding modified silica gel into the three-stage reactor after the cyclic regeneration operation for functional modification to obtain a modified catalyst;

[0012] S5. Activation and reduction: adding liquid alkali into the modified catalyst in batches, and the generated hydrogen gas is subjected to reduction reaction with copper oxide at 250-300°C, and is subjected to activation treatment at 150-200°C, to obtain the regenerated high-efficiency copper catalyst;

[0013] The preparation of the modified silica gel comprises the following steps:

[0014] S11. Silica gel pretreatment: immersing 10-15 parts of mesoporous silica gel into 50-70 parts of the modified sol, and refluxing at 70-80°C for 5-6h to obtain the preliminary modified silica gel;

[0015] S12. Ionic liquid grafting: reacting the preliminary modified silica gel with 20-40 parts of 1-butyl-3-methylimidazolium tetrafluoroborate in toluene for 10-12h, washing with ethanol for 3-4 times, and vacuum drying at 50-60°C to obtain the modified silica gel.

[0016] Preferably, the mass ratio of the screened catalyst in step S3 to the deactivated copper catalyst is 1:2.

[0017] Preferably, the cyclic regeneration operation in step S3 adopts sodium hydroxide with an end-point concentration of 15% to cyclically regenerate the catalyst packed in the three-stage reactor, and in the initial stage, the concentration of sodium hydroxide is 5%, and then the concentration of sodium hydroxide is increased by 1% every two hours, and the control time is 20h.

[0018] Preferably, the preparation of the modified sol comprises the following steps:

[0019] S111. Dissolving 7-10 parts of 3-aminopropyltriethoxysilane and 2-5 parts of mercaptopropyltrimethoxysilane in 90-100 parts of anhydrous ethanol, and adding 0.1-0.5 parts of hydrochloric acid with a mass concentration of 36-38% as a catalyst;

[0020] S112. Adding 0.5-1 parts of the composite nanoparticles into the solution obtained in step S111, and stirring at a constant temperature of 40-50°C for 4-6h, and then standing for 10-12h to obtain the modified sol.

[0021] Preferably, the preparation of the composite nanoparticles comprises the following steps:

[0022] S1121. Mixing lanthanum nitrate and cerium nitrate, and adding 10-15% ammonia water to react for 1-2h;

[0023] S1122. Centrifuging and drying the solution obtained in step S1121, and calcining at 500-600°C for 3-4h to obtain the composite nanoparticles.

[0024] Preferably, the mass ratio of the modified silica gel to the mixed catalyst obtained in step S3 is 1:5.

[0025] Preferably, the sodium hydroxide solution with a mass concentration of 10-15% is added in 3-4 batches in step S5, and each addition is separated by 20-30 min.

[0026] Preferably, the time for the reduction reaction and the activation treatment in step S5 is 2-3 h and 2-4 h, respectively.

[0027] Preferably, the mass ratio of lanthanum nitrate to cerium nitrate is 1:3.

[0028] The application also discloses application of the regenerated high-efficiency copper catalyst prepared according to the activation regeneration preparation process of the deactivated copper catalyst in production of acrylamide.

[0029] Compared with the prior art, the application has the following beneficial effects:

[0030] 1. The modified sol prepared by the composite nanoparticles can cover the surface pores of the catalyst with a uniform nano coating, the -Si-O-Si- network formed by the hydrolysis of silane catalyzed by hydrochloric acid in the sol enhances the alkali resistance and swelling resistance of the coating, reduces the penetration loss of chemical reagents in the regeneration process, prevents the agglomeration of active components, and promotes the increase of the acrylamide yield.

[0031] 2. The modified silica gel and the modified sol are used in cooperation to form a hydrophobic-hydrophilic alternating microenvironment on the surface of the silica gel, the structure can directionally adsorb reactant molecules, reduces the residence of by-products on the surface of the catalyst, optimizes the diffusion path of the reactants, reduces the generation of by-products by 20%, prolongs the service life of the catalyst by 50%, increases the oxygen vacancy density, and increases the acrylamide yield by 15%.

[0032] 3. The unique multi-step processing procedure greatly improves the regeneration efficiency of the catalyst, and compared with the traditional method, the regeneration time is greatly shortened. Meanwhile, the use amount of chemical reagents is effectively reduced in the regeneration process, and the production cost is reduced. The copper catalyst regenerated by the method has significantly improved activity and stability, can significantly improve the efficiency and product quality of related chemical reactions, and has extremely high industrial application value. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The process flow chart for improving the hydration catalytic efficiency of the copper catalyst by improving the activation process of the copper catalyst;

[0034] Figure 2 The process flow chart for preparing the modified silica gel;

[0035] Figure 3Process flow chart for preparation of modified sol of the present application.

[0036] Figure 4 Process flow chart for preparation of composite nanoparticles of the present application. DETAILED DESCRIPTION

[0037] The present application will be described in greater detail by way of specific embodiments, of which the following are examples. As will be obvious to those skilled in the art, the described embodiments are not the only way to implement the present application. Any other embodiments based on the embodiments disclosed in the present application, without departing from the spirit of the present application, are also within the scope of the present application.

[0038] Referring to Figures 1-4 The present application provides a technical solution:

[0039] During use, catalysts may change in particle size due to wear and tear, carbon deposition, and other reasons. Sieving operations can remove particles that are too large or too small. Particles that are too large may affect the distribution of fluid within the reactor, leading to uneven reactions; particles that are too small may be lost with the reactant stream, resulting in waste of catalyst. By precise sieving, the size of catalyst particles loaded into the reactor is relatively uniform, which is conducive to improving the stability and efficiency of the reaction. For example, in a fixed bed reactor, uniform particle distribution allows fluid to flow more smoothly through the catalyst bed, avoiding phenomena such as channeling, and ensuring that the reaction can be carried out under good mass and heat transfer conditions.

[0040] The mass ratio of the sieved catalyst in step S3 to the deactivated copper catalyst is 1:2, which has been verified through a large number of experiments and practical production experience. Although the activity of the old catalyst has decreased, it still retains certain catalytically active sites and structural characteristics. The newly cleaned catalyst has high initial activity. By mixing and loading them in a mass ratio of 1:2, the residual value of the old catalyst can be fully utilized, and the cost can be reduced, and the high activity of the new catalyst can drive the operation of the entire reaction system. For example, in some organic synthesis reactions, the new catalyst can quickly start the reaction, and the old catalyst gradually releases activity during the reaction, maintaining the continuous and stable progress of the reaction. The synergistic effect of the two achieves a good balance between catalytic effect and economic benefit.

[0041] Liquid alkali (sodium hydroxide) plays a key role in the catalyst regeneration process. The initial stage controls the liquid alkali concentration at about 5%, because at this time the catalyst surface needs mild conditions for preliminary cleaning and activation of impurities and deactivation substances. As the reactor temperature rises, the activity of the catalyst gradually recovers, and its reactivity with liquid alkali also increases. Slowly increasing the liquid alkali concentration to about 15% at the end point can gradually and deeply remove stubborn impurities on the catalyst surface, such as carbon deposition and metal oxides, while promoting the re-exposure and recovery of the catalyst active sites. For example, for a catalyst deactivated by adsorbing organic pollutants, low concentration liquid alkali first dissolves part of the easily soluble impurities, and as the concentration increases, the stronger alkaline environment can break the chemical bond between the organic pollutants and the catalyst surface, completely removing them and effectively recovering the activity of the catalyst.

[0042] Example 1

[0043] An activation regeneration process for a deactivated copper catalyst:

[0044] Before implementing the improved method, the preparation of modified silica gel is carried out:

[0045] S11. Silica gel pretreatment: immerse 20g mesoporous silica gel in 100g modified sol, reflux at 70℃ for 5h, to obtain preliminary modified silica gel;

[0046] S12. Ionic liquid grafting: react the preliminary modified silica gel with 40g 1-butyl-3-methylimidazolium tetrafluoroborate in toluene for 10h, wash with ethanol for 3 times, and dry at 50℃ under vacuum to obtain modified silica gel;

[0047] The preparation of the above modified sol includes the following steps:

[0048] S111. Dissolve 70g 3-aminopropyltriethoxysilane and 20g mercaptopropyltrimethoxysilane in 900ml anhydrous ethanol, and add 1ml 36% mass concentration hydrochloric acid as catalyst;

[0049] S112. Add 5g composite nanoparticles to the solution obtained in step S111, stir at 40℃ for 4h, and then stand for 10h to obtain a modified sol;

[0050] The preparation of the above composite nanoparticles includes the following steps:

[0051] S1121. Mix 10g lanthanum nitrate and 30g cerium nitrate, and add 10% mass concentration ammonia water to react for 1h;

[0052] S1122. Centrifuge and dry the solution obtained in step S1121, and calcine at 500℃ for 3h to obtain composite nanoparticles;

[0053] S1. Washing and alkali treatment: 200 g of newly added copper catalyst was washed with deionized water for 4 times, and then soaked in a 5% mass concentration sodium hydroxide solution for 18 h to obtain a pretreated catalyst;

[0054] S2. Washing: the pretreated catalyst was soaked in deionized water at 60°C for 18 h to obtain an alkali-removed treated catalyst;

[0055] S3. Mixed loading: the alkali-removed treated catalyst was mixed with 400 g of deactivated copper catalyst to be uniformly mixed, and then sequentially loaded into a three-stage reactor for a cyclic regeneration operation. Sodium hydroxide with a final concentration of 15% was used for the cyclic regeneration operation of the catalyst loaded in the three-stage reactor. In the initial stage, the concentration of sodium hydroxide was 5%, and then the concentration of sodium hydroxide was increased by 1% every two hours, and the control time was 20 h;

[0056] S4. Functional modification of modified silica gel: 120 g of modified silica gel was added to the three-stage reactor after the cyclic regeneration operation for functional modification to obtain a modified catalyst;

[0057] S5. Activation and reduction: 10% mass concentration sodium hydroxide solution was added to the modified catalyst in three times with an interval of 20 min. The generated hydrogen was subjected to a reduction reaction with copper oxide at 250°C for 2 h, and then subjected to an activation treatment at 150°C for 2 h to obtain a regenerated high-efficiency copper catalyst.

[0058] Example 2

[0059] A preparation process for activation and regeneration of a deactivated copper catalyst:

[0060] Before implementing the improved method, the preparation of modified silica gel was carried out:

[0061] S11. Silica gel pretreatment: 30 g of mesoporous silica gel was immersed in 140 g of modified sol, and refluxed at 80°C for 6 h to obtain a preliminary modified silica gel;

[0062] S12. Ionic liquid grafting: the preliminary modified silica gel was reacted with 80 g of 1-butyl-3-methylimidazolium tetrafluoroborate in toluene for 12 h, washed with ethanol for 4 times, and vacuum dried at 60°C to obtain modified silica gel;

[0063] The preparation of the above modified sol includes the following steps:

[0064] S111. 100 g of 3-aminopropyltriethoxysilane and 50 g of mercaptopropyltrimethoxysilane were dissolved in 1000 ml of anhydrous ethanol, and 5 ml of 38% mass concentration hydrochloric acid was added as a catalyst;

[0065] S112. 10g of the composite nanoparticles were added to the solution obtained in step S111, and stirred at 50℃ for 6h, and then allowed to stand for 12h to obtain a modified sol;

[0066] The preparation of the composite nanoparticles includes the following steps:

[0067] S1121. 10g of lanthanum nitrate and 30g of cerium nitrate were mixed, and then added to 15% ammonia water to react for 2h;

[0068] S1122. The solution obtained in step S1121 was centrifuged, washed and dried, and then calcined at 600℃ for 4h to obtain the composite nanoparticles;

[0069] S1. Washing and alkali treatment: 200g of newly added copper catalyst was washed with deionized water for 5 times, and then immersed in 10% sodium hydroxide solution for 20h to obtain a pretreated catalyst;

[0070] S2. Washing: the pretreated catalyst was immersed in 70℃ deionized water for 20h to obtain a catalyst after alkali removal treatment;

[0071] S3. Mixed packing: the catalyst after alkali removal treatment was mixed with 400g of deactivated copper catalyst, and then sequentially packed into three reactors for cyclic regeneration operation. The catalysts packed in the three reactors were subjected to cyclic regeneration operation using 15% sodium hydroxide as the end point. In the initial stage, the concentration of sodium hydroxide was 5%, and then the concentration of sodium hydroxide was increased by 1% every two hours, and the control time was 20h;

[0072] S4. Modification of the modified silica gel: 120g of modified silica gel was added to the three reactors after the cyclic regeneration operation for functional modification to obtain a modified catalyst;

[0073] S5. Activation and reduction: 15% sodium hydroxide solution was added to the modified catalyst in four times with an interval of 30min, and the generated hydrogen was subjected to reduction reaction with copper oxide at 300℃ for 3h, and then subjected to activation treatment at 200℃ for 4h to obtain a regenerated high-efficiency copper catalyst.

[0074] Example 3

[0075] A preparation process for activation and regeneration of a deactivated copper catalyst:

[0076] Before the improved method is implemented, the preparation of modified silica gel is performed:

[0077] S11. Silica gel pretreatment: 22g of mesoporous silica gel was immersed in 120g of modified sol, and then refluxed at 74℃ for 5.5h to obtain a preliminary modified silica gel;

[0078] S12. Ionic liquid grafting: the preliminary modified silica gel is reacted with 50 g of 1-butyl-3-methylimidazolium tetrafluoroborate in toluene for 11 h, washed with ethanol for 3 times, and vacuum dried at 54°C to obtain the modified silica gel;

[0079] The preparation of the modified sol comprises the following steps:

[0080] S111. 80 g of 3-aminopropyltriethoxysilane and 30 g of mercaptopropyltrimethoxysilane are dissolved in 940 ml of anhydrous ethanol, and 2 ml of hydrochloric acid with a mass concentration of 37% is added as a catalyst;

[0081] S112. 7 g of the composite nanoparticles are added to the solution obtained in step S111, and stirred at a constant temperature of 44°C for 5 h, and then aged for 11 h after a uniform sol is formed, to obtain a modified sol;

[0082] The preparation of the composite nanoparticles comprises the following steps:

[0083] S1121. 10 g of lanthanum nitrate and 30 g of cerium nitrate are mixed, and reacted in ammonia water with a mass concentration of 12% for 1.5 h;

[0084] S1122. The solution obtained in step S1121 is centrifuged, washed and dried, and calcined at 550°C for 3.5 h to obtain the composite nanoparticles;

[0085] S1. Washing and alkali treatment: 200 g of a newly added copper catalyst is washed with deionized water for 4 times, and then soaked in a sodium hydroxide solution with a mass concentration of 7% for 19 h to obtain a pretreated catalyst;

[0086] S2. Washing: the pretreated catalyst is soaked in deionized water at 64°C for 19 h to obtain an alkali-removed treated catalyst;

[0087] S3. Mixed packing: the alkali-removed treated catalyst is mixed with 400 g of an inactivated copper catalyst to be uniformly mixed, and sequentially packed into three-stage reactors for a cyclic regeneration operation, and sodium hydroxide with a final concentration of 15% is used for the cyclic regeneration operation of the catalyst packed in the three-stage reactors, in the initial stage, the concentration of sodium hydroxide is 5%, and then the concentration of sodium hydroxide is increased by 1% every two hours, and the control time is 20 h;

[0088] S4. Functional modification of modified silica gel: 120 g of modified silica gel is added to the three-stage reactors after the cyclic regeneration operation for functional modification to obtain a modified catalyst;

[0089] S5. Activation and reduction: 12% sodium hydroxide solution was added to the modified catalyst in three times with 24 min interval, the generated hydrogen was reacted with copper oxide at 270℃ for 2.5h and activated at 170℃ for 3h to obtain the regenerated high-efficiency copper catalyst.

[0090] Example 4

[0091] A preparation process for activation and regeneration of an inactivated copper catalyst:

[0092] Preparation of modified silica gel before implementing the improved method:

[0093] S11. Silica gel pretreatment: 28g mesoporous silica gel was immersed in 130g modified sol, and refluxed at 78℃ for 5.5h to obtain the preliminary modified silica gel;

[0094] S12. Ionic liquid grafting: the preliminary modified silica gel was reacted with 70g 1-butyl-3-methylimidazolium tetrafluoroborate in toluene for 11h, washed with ethanol for 4 times, and vacuum dried at 58℃ to obtain the modified silica gel;

[0095] The preparation of the above modified sol includes the following steps:

[0096] S111. 90g 3-aminopropyltriethoxysilane and 40g mercaptopropyltrimethoxysilane were dissolved in 980ml anhydrous ethanol, and 4ml 37% hydrochloric acid was added as a catalyst;

[0097] S112. 9g composite nanoparticles were added to the solution obtained in step S111, and stirred at 58℃ for 5.5h, and then aged for 11.5h after forming a uniform sol to obtain a modified sol;

[0098] The preparation of the above composite nanoparticles includes the following steps:

[0099] S1121. 10g lanthanum nitrate and 30g cerium nitrate were mixed and reacted with 14% ammonia water for 1.5h;

[0100] S1122. The solution obtained in step S1121 was centrifuged, washed and dried, and calcined at 580℃ for 3.5h to obtain the composite nanoparticles;

[0101] S1. Washing and alkali treatment: 200g newly added copper catalyst was washed with deionized water for 5 times, and then soaked in 9% sodium hydroxide solution for 19h to obtain a pretreated catalyst;

[0102] S2. Washing: the pretreated catalyst was soaked in 68℃ deionized water for 19h to obtain a catalyst after alkali removal treatment;

[0103] S3. Mixed loading: After the dealkalization treatment, the catalyst was mixed with 400 g of deactivated copper catalyst to form a mixture, which was then loaded into the three-stage reactor for cyclic regeneration. Sodium hydroxide with a final concentration of 15% was used for the cyclic regeneration of the catalyst loaded in the three-stage reactor. In the initial stage, the concentration of sodium hydroxide was 5%, and then the concentration of sodium hydroxide was increased by 1% every two hours, with a control time of 20 h.

[0104] S4. Functional modification of modified silica gel: 120 g of modified silica gel was added to the three-stage reactor after the cyclic regeneration operation for functional modification, and a modified catalyst was obtained.

[0105] S5. Activation and reduction: 14% sodium hydroxide solution was added to the modified catalyst in four stages, with an interval of 28 min each time. The generated hydrogen gas was subjected to a reduction reaction with copper oxide at 280°C for 2.5 h, and then an activation treatment was performed at 180°C for 3.5 h, obtaining a regenerated high-efficiency copper catalyst.

[0106] Comparative Example 1

[0107] In this comparative example, the copper catalyst was treated using a traditional regeneration method, i.e., only through the steps of washing, drying, and activation.

[0108] Performance test:

[0109] In a fixed bed reactor, the temperature was set to 80°C, the pressure was 1.5 MPa, and the mass concentration of acrylonitrile aqueous solution was 20%. The flow rate was controlled at 50 mL / min, and the regenerated high-efficiency copper catalyst obtained from Examples 1-4 and Comparative Example 1 was used as the catalyst. The yield of acrylamide after 1 hour of reaction was recorded, and the data obtained are shown in Table 1 below:

[0110] Table 1

[0111] Acrylamide yield (%) Example 1 83.4±0.8 Example 2 84.1±0.7 Example 3 83.8±0.9 Example 4 84.5±0.6 Comparative Example 1 72.5±1.2

[0112] The average yield of acrylamide in the examples was 83.9%, which was about 15.7% higher than that of the control group (72.5%). The yield improvement was attributed to the combined use of modified silica gel and modified sol, which increased the oxygen vacancy density and surface active site coverage of the catalyst, resulting in an increase in the yield of acrylamide.

[0113] The regenerated catalysts from Example 3 and Comparative Example 1 were continuously operated for 200 hours, and the acrylamide yield was tested every 24 hours. The stability of the regenerated catalysts from Example 3 and Comparative Example 1 was compared, and the data obtained are shown in Table 2 below:

[0114] Table 2

[0115] Run time (h) Comparative Example 1 yield (%) Example 3 yield (%) 24 71.8±1.1 83.5±0.8 100 65.2±1.5 80.1±1.0 200 58.4±2.0 77.6±1.2

[0116] The catalyst of Example 3 still maintained a yield of 77.6% after 200 hours, which was significantly improved compared to Comparative Example 1 (58.4%), and the life was prolonged by about 50%. The ionic liquid grafted layer of the modified silica gel effectively inhibited the carbon deposition and metal sintering, and maintained the pore structure and active sites of the catalyst.

[0117] While embodiments of the present application have been shown and described with reference to particular embodiments thereof, it will be understood by those skilled in the art that various changes in form and details can be made therein without departing from the spirit and scope of the application as defined by the appended claims and their equivalents.

Claims

1. An activation regeneration process for producing a deactivated copper catalyst for the production of acrylamide, characterized in that, The method comprises the following steps: S1. Washing and alkali treatment: the newly added copper catalyst is washed with deionized water for 4-5 times, and then soaked in a sodium hydroxide solution with a mass concentration of 5-10% for 18-20 h to obtain a pretreated catalyst; S2. Cleaning: the pretreated catalyst is soaked in deionized water at 60-70 ℃ for 18-20 h to obtain a catalyst after alkali removal treatment; S3. Mixed loading: the catalyst after alkali removal treatment is mixed with the deactivated copper catalyst, and then loaded into a three-stage reactor in sequence for a cyclic regeneration operation; S4. Modification of modified silica gel: the modified silica gel is added into the three-stage reactor after the cyclic regeneration operation for functional modification to obtain a modified catalyst; S5. Activation and reduction: liquid alkali is added into the modified catalyst in batches, hydrogen generated is subjected to a reduction reaction with copper oxide at 250-300 ℃, and activation treatment is performed at 150-200 ℃ to obtain a regenerated high-efficiency copper catalyst; The preparation of the modified silica gel comprises the following steps: S11. Silica gel pretreatment: 10-15 parts of mesoporous silica gel are immersed in 50-70 parts of modified sol, and reflux reaction is performed at 70-80 ℃ for 5-6 h to obtain preliminary modified silica gel; S12. Ionic liquid grafting: the preliminary modified silica gel is reacted with 20-40 parts of 1-butyl-3-methylimidazolium tetrafluoroborate in toluene for 10-12 h, washed with ethanol for 3-4 times, and vacuum dried at 50-60 ℃ to obtain modified silica gel; The preparation of the modified sol comprises the following steps: S111. 7-10 parts of 3-aminopropyltriethoxysilane and 2-5 parts of mercaptopropyltrimethoxysilane are dissolved in 90-100 parts of anhydrous ethanol, and 0.1-0.5 parts of hydrochloric acid with a mass concentration of 36-38% is added as a catalyst; S112. 0.5-1 parts of composite nanoparticles are added into the solution obtained in step S111, constant temperature stirring is performed at 40-50 ℃ for 4-6 h, and after the formation of a uniform sol, standing and ripening are performed for 10-12 h to obtain a modified sol; The preparation of the composite nanoparticles comprises the following steps: S1121. Lanthanum nitrate and cerium nitrate are mixed, and 10-15% ammonia water is added for reaction for 1-2 h; S1122. The solution obtained in step S1121 is centrifuged, washed and dried, and calcination is performed at 500-600 ℃ for 3-4 h to obtain composite nanoparticles.

2. A process for the activation and regeneration of a deactivated copper catalyst for the production of acrylamide according to claim 1, characterized in that, The mass ratio of the catalyst after screening in step S3 to the deactivated copper catalyst is 1:

2.

3. A process for the activation and regeneration of a deactivated copper catalyst for the production of acrylamide according to claim 1, characterized in that, The cyclic regeneration operation in step S3 adopts sodium hydroxide with a final concentration of 15% to cyclically regenerate the catalyst loaded in the three-stage reactor, in the initial stage, the concentration of sodium hydroxide is 5%, and then the concentration of sodium hydroxide is increased by 1% every two hours, and the control time is 20 h.

4. A process for the activation and regeneration of a deactivated copper catalyst for the production of acrylamide according to claim 1, characterized in that, The mass ratio of the modified silica gel to the mixed catalyst obtained in step S3 is 1:

5.

5. A process for the activation and regeneration of a deactivated copper catalyst for the production of acrylamide according to claim 1, characterized in that, In step S5, the liquid alkali is added in batches, specifically: 10-15% sodium hydroxide solution is added in 3-4 times, and each time interval is 20-30 min.

6. A process for the activation and regeneration of a deactivated copper catalyst for the production of acrylamide according to claim 1, characterized in that, The reduction reaction and activation treatment in step S5 are performed for 2-3 h and 2-4 h, respectively.

7. A process for the activation and regeneration of a deactivated copper catalyst for the production of acrylamide according to claim 1, characterized in that, The mass ratio of lanthanum nitrate and cerium nitrate is 1:

3.

8. The use of the regenerated high-efficiency copper catalyst prepared by the activation regeneration process for preparing an inactivated copper catalyst for producing acrylamide in the production of acrylamide.

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