Preparation method for catalyst for dehydration-condensation reduction reaction, resulting product and use

Abstract

Disclosed in the present invention are a preparation method for a catalyst for a dehydration-condensation reduction reaction, the resulting product and the use. The preparation method comprises the following steps: spreading activated carbon evenly in a fixed bed, then continuously introducing a mixed solution of copper nitrate, zinc nitrate and zirconium nitrate into the fixed bed, and enabling the mixed solution to be in full contact with an activated carbon layer; roasting the activated carbon which is in full contact with the mixed solution, so as to obtain activated carbon loaded with copper oxide-zinc oxide-zirconium oxide; and dispersing the active carbon loaded with copper oxide-zinc oxide-zirconium oxide into an organic solvent, then adding a sulfiding agent, subjecting same to a sulfurization reaction, and filtering, washing and drying same after the reaction, so as to obtain the catalyst for a dehydration condensation reduction reaction. The preparation method for a catalyst of the present invention is simple and convenient to operate, low in cost and small in environmental pollution, can be applied to the dehydration condensation reduction reaction of various ketones or aldehydes and amines, improves the selectivity of the reaction, reduces side reaction products, and has a good catalytic effect and industrial development prospects.

Description

A method for preparing a catalyst for a dehydration condensation reduction reaction, the resulting product, and its application. Technical Field

[0001] This invention relates to a method for preparing a catalyst for a dehydration condensation reduction reaction and the resulting product, and also to the application of the catalyst in the hydrogenation reaction of aldehydes or ketones with amines. Background Technology

[0002] The dehydration condensation reduction of aldehydes and ketones with amines has important applications in the preparation of primary, secondary, and tertiary amines. Organic amine compounds are widely used in pesticides, pharmaceuticals, dyes, surfactants, rubber additives, and many other fields, playing a vital role in industrial and agricultural production as well as daily life.

[0003] Catalytic hydrogenation is a very traditional method. In this method, carbonyl compounds and amines are dehydrated and condensed under a reducing atmosphere and a reducing catalyst in the presence of hydrogenation catalysts such as nickel, palladium, and platinum to obtain the target amine.

[0004] With the increasingly widespread application of the dehydration condensation reduction reaction of aldehydes, ketones, and amines, research on it has become more in-depth. Metal-supported catalysts exhibit high catalytic activity and produce a variety of hydrogenation byproducts in this reaction. Particularly in the synthesis of the mainstream antioxidant 4020, approximately 17% of the raw material methyl isobutyl ketone (MIBK) is hydrogenated to methyl isobutyl methanol (MIBC) using copper as a catalyst. Because these catalysts have strong hydrocracking performance and high activity in the initial stages of operation, the reaction rate can easily become too fast, potentially leading to overheating, which can damage the catalyst and reactor, increasing safety risks, production costs, and reducing production efficiency. Summary of the Invention

[0005] To address the problems of existing catalysts, this invention provides a method for preparing a catalyst for dehydration condensation reduction reaction and the resulting catalyst. This invention uses a special process to load copper oxide-zinc oxide-zirconia onto activated carbon, which can appropriately weaken the hydrogenation catalytic performance of the catalyst, regulate the selectivity in the chemical reaction, reduce side reactions in the dehydration condensation reduction reaction, and improve the yield of the main product.

[0006] This invention is achieved through the following technical solution:

[0007] A method for preparing a catalyst for a dehydration condensation reduction reaction, the method comprising the following steps:

[0008] (1) Spread activated carbon evenly in a fixed bed, and then continuously pass a mixed solution of copper nitrate, zinc nitrate and zirconium nitrate into the fixed bed so that the mixed solution is in full contact with the activated carbon layer;

[0009] (2) The activated carbon that has been in full contact with the mixed solution is calcined to obtain activated carbon loaded with copper oxide-zinc oxide-zirconia;

[0010] (3) Disperse the activated carbon loaded with copper oxide-zinc oxide-zirconia into an organic solvent, then add a sulfiding agent to carry out a sulfidation reaction. After the reaction, filter, wash and dry to obtain a catalyst for dehydration condensation reduction reaction.

[0011] Furthermore, in step (1), the specific surface area of ​​the activated carbon is 1250-1350 m² / g.

[0012] Furthermore, in step (1), the thickness of the activated carbon layer on the fixed bed is 1.3-1.8 cm.

[0013] Furthermore, in step (1), the mixed solution is obtained by mixing copper nitrate, zinc nitrate, zirconium nitrate and water, and there are no special requirements for the mixing order of the raw materials.

[0014] Furthermore, in step (1), the concentration of copper nitrate in the mixed solution is 1-5 g / 100 ml, for example, 1 g / 100 ml, 2 g / 100 ml, 3 g / 100 ml, 4 g / 100 ml, or 5 g / 100 ml. Preferably, the concentration of copper nitrate is 3 g / 100 ml.

[0015] Furthermore, in step (1), the concentration of zinc nitrate in the mixed solution is 3-7 g / 100 ml, for example 3 g / 100 ml, 4 g / 100 ml, 5 g / 100 ml, 6 g / 100 ml, 7 g / 100 ml, preferably 4 g / 100 ml.

[0016] Further, in step (1), the concentration of zirconium nitrate in the mixed solution is 1-5 g / 100 ml, for example 1 g / 100 ml, 2 g / 100 ml, 3 g / 100 ml, 4 g / 100 ml, 5 g / 100 ml, preferably 2 g / 100 ml.

[0017] Furthermore, in step (1), the mixed solution passes through the activated carbon layer at a certain speed, allowing the metal salt in the mixed solution to fully contact the activated carbon, thereby achieving the loading of the metal salt on the activated carbon. The flow rate of the mixed solution is 1-10 ml / min, for example, 1 ml / min, 2 ml / min, 3 ml / min, 4 ml / min, 5 ml / min, 6 ml / min, 7 ml / min, 8 ml / min, 9 ml / min, 10 ml / min, preferably 5 ml / min.

[0018] Furthermore, in step (1), the temperature when the mixed solution comes into contact with the activated carbon layer is 25-45°C, for example, 25°C, 30°C, 35°C, or 40°C, preferably 35°C. The contact time between the mixed solution and the activated carbon layer is 0.5-2 hours, for example, 0.5 hours, 1 hour, 1.5 hours, or 2 hours, preferably 1 hour.

[0019] Furthermore, in step (1), the final loading of nitrate on activated carbon can be controlled by adjusting the concentration of the mixed solution, the flow rate, and the contact time. In a specific embodiment of the present invention, the final loading of copper nitrate on activated carbon is 10-12%, the loading of zinc nitrate on activated carbon is 7-8%, and the loading of zirconium nitrate on activated carbon is 5-7%. The loading is calculated as the mass of a specific nitrate / (total mass of activated carbon and nitrate) * 100%.

[0020] Furthermore, in step (2), the roasting can be carried out in a muffle furnace under an air atmosphere.

[0021] Furthermore, in step (2), the roasting temperature is 400-800℃, for example 400℃, 450℃, 500℃, 550℃, 600℃, 650℃, 700℃, 750℃, 800℃, preferably 500℃.

[0022] Furthermore, in step (2), the roasting time is 2-6 hours, for example 2 hours, 3 hours, 4 hours, 5 hours, or 6 hours, preferably 4 hours.

[0023] Furthermore, in step (3), the activated carbon loaded with copper oxide-zinc oxide-zirconia obtained by calcination can be dispersed in an organic solvent by stirring, ultrasound, etc., and the organic solvent is an alcohol, such as methanol, ethanol, isopropanol, etc., preferably methanol.

[0024] Furthermore, in step (3), the mass ratio of activated carbon loaded with copper oxide-zinc oxide-zirconia to organic solvent is 1:6-10, for example 1:6, 1:7, 1:8, 1:9, 1:10.

[0025] Furthermore, in step (3), the vulcanizing agent is at least one of dimethyl sulfide, dodecathionol, dimethyl sulfoxide, diphenyl sulfide, and diphenyl disulfide, preferably a mixture of diphenyl sulfide and diphenyl disulfide.

[0026] Furthermore, when the vulcanizing agent is a mixture of diphenyl sulfide and diphenyl disulfide, the mass ratio of diphenyl sulfide to diphenyl disulfide is 1:1 to 1.5, preferably 1:1.2.

[0027] Furthermore, in step (3), the mass ratio of activated carbon loaded with copper oxide-zinc oxide-zirconia to sulfiding agent is 5:0.1-1, for example 5:0.1, 5:0.2, 5:0.3, 5:0.4, 5:0.5, 5:0.6, 5:0.7, 5:0.8, 5:0.9, 5:1.0, preferably 5:0.5.

[0028] Furthermore, in step (3), the vulcanizing agent is preferably added by dripping, with the dripping time controlled at 2-5 minutes and the temperature during dripping at 25-45°C, such as 25°C, 30°C, 35°C, 40°C, or 45°C, preferably 35°C.

[0029] Furthermore, in step (3), after the vulcanizing agent is added, the reaction is continued at 25-45°C, for example, 25°C, 30°C, 35°C, 40°C, or 45°C, preferably 35°C. The reaction time is 0.5-2 hours, for example, 0.5 hours, 1 hour, 1.5 hours, or 2 hours, preferably 1 hour.

[0030] Furthermore, in step (3), after vulcanization is completed, the product is filtered, washed, and dried to obtain the product of the present invention.

[0031] The catalyst used in the dehydration condensation reduction reaction of this invention has good selectivity and can be applied to the dehydration condensation reduction reaction of various ketones or aldehydes with amines. Therefore, the catalyst and its application in the dehydration condensation reduction reaction of aldehydes with amines or ketones with amines are also within the scope of protection of this invention.

[0032] The present invention has the following beneficial effects:

[0033] 1. The method of the present invention is simple to operate, has mild synthesis conditions, low risk, low cost, and minimal environmental pollution.

[0034] 2. This invention uses activated carbon as a carrier, loads copper, zinc, and zirconium ions, and then calcines it at high temperature to obtain a carbon-based catalyst supported on composite oxides. The catalyst is then passivated using a sulfiding agent to obtain the final activated carbon-supported CuO-ZnO-ZrO2-S catalyst. This catalyst has convenient raw material purchase and transportation, appropriately weakens its hydrogenation catalytic performance, and can be applied to the dehydration condensation reduction reactions of various ketones or aldehydes with amines, improving reaction selectivity, reducing side reaction products, and exhibiting good catalytic effect. Detailed Implementation

[0035] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the specific implementation method and effects of a novel catalyst preparation method and its application in antioxidant synthesis based on the present invention are described in detail below.

[0036] In the following examples and comparative examples, the activated carbon used was purchased from the market and had a specific surface area of ​​1250-1350 m² / g.

[0037] Example 1

[0038] A method for preparing a catalyst for a dehydration condensation reduction reaction, the specific synthesis steps of which are as follows:

[0039] Step 1: Load

[0040] Weigh 5g of activated carbon and fill it into a fixed bed to a thickness of 1.5cm. Dissolve copper nitrate, zinc nitrate, and zirconium nitrate in water and mix thoroughly to obtain a mixed solution with a copper nitrate concentration of 2g / 100ml, a zinc nitrate concentration of 4g / 100ml, and a zirconium nitrate concentration of 2g / 100ml. Pass the mixed solution through the fixed bed at 35℃ at a rate of 3ml / min, ensuring continuous contact between the activated carbon and the mixed solution for 1 hour. After completion, wash the solution and determine the content of copper nitrate, zinc nitrate, and zirconium nitrate in the remaining mixed solution. Calculate the loading of activated carbon using the difference method. The loading of copper nitrate on the activated carbon is approximately 10%, the loading of zinc nitrate is approximately 8%, and the loading of zirconium nitrate is approximately 7%. Loading = (mass of metal salts / (mass of activated carbon + total mass of metal salts)) * 100%.

[0041] Step 2: Roasting

[0042] Activated carbon loaded with metal ions was placed in a muffle furnace and calcined at 400°C in air atmosphere. After 3 hours, it was cooled to obtain a carbon-based copper oxide-zinc oxide-zirconia catalyst.

[0043] Step 3: Vulcanization

[0044] At 25°C, 5g of carbon-based copper oxide-zinc oxide-zirconia catalyst was added to 30g of organic solvent ethanol and stirred thoroughly to disperse evenly. Then, 0.3g of a mixture of diphenyl sulfide and diphenyl disulfide in a mass ratio of 1:1.4 was added dropwise using a pipette over a period of 3 minutes. After the addition was complete, the mixture was sulfided at 25°C for 0.5 hours. The mixture was then filtered, the solid was washed, and dried in an oven to obtain the catalyst product of this invention.

[0045] Example 2

[0046] A method for preparing a catalyst for a dehydration condensation reduction reaction, the specific synthesis steps of which are as follows:

[0047] Step 1: Load

[0048] Weigh 5g of activated carbon and fill it into a fixed bed to a thickness of 1.5cm. Dissolve copper nitrate, zinc nitrate, and zirconium nitrate in water and mix thoroughly to obtain a mixed solution with a copper nitrate concentration of 3g / 100ml, a zinc nitrate concentration of 4g / 100ml, and a zirconium nitrate concentration of 2g / 100ml. Pass the mixed solution through the fixed bed at 35℃ at a rate of 5ml / min, allowing the activated carbon to remain in contact with the mixed solution for 0.5h. After completion, wash the solution and determine the contents of copper nitrate, zinc nitrate, and zirconium nitrate in the remaining mixed solution. Calculate the loading of activated carbon using the difference method. The loading of copper nitrate on the activated carbon is approximately 12%, the loading of zinc nitrate is approximately 7%, and the loading of zirconium nitrate is approximately 6%.

[0049] Step 2: Roasting

[0050] Activated carbon loaded with metal ions was placed in a muffle furnace and calcined at 500°C in air atmosphere. After 4 hours, it was cooled to obtain a carbon-based copper oxide-zinc oxide-zirconia catalyst.

[0051] Step 3: Vulcanization

[0052] At 25°C, 5g of carbon-based copper oxide-zinc oxide-zirconia catalyst was added to 30g of organic solvent methanol and stirred thoroughly to disperse it evenly. Then, 0.5g of a mixture of diphenyl sulfide and diphenyl disulfide in a mass ratio of 1:1.3 was added dropwise using a pipette over a period of 3 minutes. After the addition was complete, the mixture was sulfided at 25°C for 1 hour. The mixture was then filtered, the solid was washed, and dried in an oven to obtain the catalyst product of this invention.

[0053] Example 3

[0054] The catalyst for the dehydration condensation reduction reaction was prepared according to the method of Example 2, except that in step 3, 0.5 g of diphenyl sulfide and diphenyl disulfide in a mass ratio of 1:1.3 were replaced with 1 g of diphenyl sulfide, and the dropping time was 3 min.

[0055] Example 4

[0056] The catalyst for the dehydration condensation reduction reaction was prepared according to the method of Example 2, except that in step 3, 0.5 g of diphenyl sulfide and diphenyl disulfide in a mass ratio of 1:1.3 were replaced with 0.5 g of a mixture of dimethyl sulfide and diphenyl disulfide in a mass ratio of 1:1.2, and the addition time was 3 min.

[0057] Example 5

[0058] The catalyst for the dehydration condensation reduction reaction was prepared according to the method in Example 2, except that in step 1, 5g of activated carbon was weighed and packed into a fixed bed with a thickness of 1.5cm. Copper nitrate, zinc nitrate, and zirconium nitrate were dissolved in water and mixed evenly to obtain a mixed solution with a copper nitrate concentration of 5g / 100ml, a zinc nitrate concentration of 7g / 100ml, and a zirconium nitrate concentration of 5g / 100ml. The mixed solution was passed through the fixed bed at 45°C at a rate of 10ml / min, allowing the activated carbon to remain in contact with the mixed solution for 0.5h. After completion, the solution was washed, and the contents of copper nitrate, zinc nitrate, and zirconium nitrate in the remaining mixed solution were determined. The loading of activated carbon was calculated using the difference method. The loading of copper nitrate on the activated carbon was approximately 10%, the loading of zinc nitrate was approximately 7%, and the loading of zirconium nitrate was approximately 5%.

[0059] Comparative Example 1

[0060] A method for preparing a catalyst for a dehydration condensation reduction reaction, the specific synthesis steps of which are as follows:

[0061] Step 1: Load

[0062] Weigh 5g of activated carbon and fill it into a fixed bed to a thickness of 1.5cm. Dissolve copper nitrate, zinc nitrate, and zirconium nitrate in water and mix thoroughly to obtain a mixed solution with a copper nitrate concentration of 3g / 100ml, a zinc nitrate concentration of 4g / 100ml, and a zirconium nitrate concentration of 2g / 100ml. Pass the mixed solution through the fixed bed at 35℃ at a rate of 5ml / min, allowing the activated carbon to remain in contact with the mixed solution for 0.5h. After completion, wash the solution and determine the contents of copper nitrate, zinc nitrate, and zirconium nitrate in the remaining mixed solution. Calculate the loading of activated carbon using the difference method. The loading of copper nitrate on the activated carbon is approximately 12%, the loading of zinc nitrate is approximately 7%, and the loading of zirconium nitrate is approximately 6%.

[0063] Step 2: Roasting

[0064] Activated carbon loaded with metal ions was placed in a muffle furnace and calcined at 500°C in air atmosphere. After 4 hours, it was cooled to obtain a carbon-based copper oxide-zinc oxide-zirconia catalyst.

[0065] Comparative Example 2

[0066] The catalyst for the dehydration condensation reduction reaction was prepared according to the method in Example 2, except that in step 1, copper nitrate, zinc nitrate, and zirconium nitrate were dissolved in water and mixed thoroughly to obtain a mixed solution with a copper nitrate concentration of 3 g / 100 ml, a zinc nitrate concentration of 4 g / 100 ml, and a zirconium nitrate concentration of 2 g / 100 ml. 5 g of activated carbon was added to 30 g of the mixed solution, and the mixture was stirred at 35°C for 0.5 h. After the reaction, the carbon was washed, and the loading was determined using the difference method. The loading of copper nitrate on the activated carbon was approximately 8%, the loading of zinc nitrate was approximately 6%, and the loading of zirconium nitrate was approximately 5%.

[0067] Comparative Example 3

[0068] The catalyst for the dehydration condensation reduction reaction was prepared according to the method in Example 2, except that in step 1, 5g of activated carbon was weighed and filled into a fixed bed with a thickness of 1.5cm. Copper nitrate was dissolved in water and mixed evenly to obtain a solution with a copper nitrate concentration of 3g / 100ml. The copper nitrate solution was passed through the fixed bed at 35°C at a rate of 5ml / min, allowing the activated carbon to remain in contact with the mixed solution for 2 hours. After completion, the solution was washed, and the copper nitrate content in the remaining mixed solution was measured. The loading of activated carbon was calculated using the difference method, and the copper nitrate loading on the activated carbon was approximately 17%.

[0069] Comparative Example 4

[0070] The catalyst for the dehydration condensation reduction reaction was prepared according to the method in Example 2, except that in step 1, 5g of activated carbon was weighed and packed into a fixed bed with a thickness of 1.5cm. Copper nitrate and zinc nitrate were dissolved in water and mixed evenly to obtain a solution with a copper nitrate concentration of 3g / 100ml and a zinc nitrate concentration of 4g / 100ml. The copper nitrate solution was passed through the fixed bed at 35°C at a rate of 5ml / min, allowing the activated carbon to be in continuous contact with the mixed solution for 0.8h. After completion, the solution was washed, and the copper nitrate content in the remaining mixed solution was determined. The loading of activated carbon was calculated using the difference method, and the copper nitrate loading on the activated carbon was approximately 13% and the zinc nitrate loading was approximately 11%.

[0071] Application Example 1

[0072] 18.4 g of 4-aminodiphenylamine, 50 g of methyl isobutyl ketone, and 3 g of the catalyst from Example 2 were added to a 100 mL high-pressure reactor. Hydrogen gas was then introduced to a pressure of 3-4 MPa, and the reaction temperature was controlled at 120 °C to carry out ketone-amine dehydration condensation. When the hydrogen pressure dropped below 2 MPa, hydrogen gas was introduced to a pressure of 3-4 MPa until the hydrogen pressure no longer decreased. After the reaction was completed, no byproduct methyl isobutyl methanol was detected in the mother liquor. The remaining ketone and water were removed under reduced pressure to obtain 26.29 g of the final antioxidant product. The liquid chromatography purity (HPLC) was 99.2% (after deducting the ketone content), and the product yield based on 4-aminodiphenylamine was 98.91%.

[0073] Application Example 2

[0074] 18.4 g of 4-aminodiphenylamine, 46.4 g of acetone, and 3 g of the catalyst from Example 2 were added to a 100 mL high-pressure reactor. Hydrogen gas was then introduced to a pressure of 3-4 MPa, and the reaction temperature was controlled at 120 °C to carry out ketone-amine dehydration condensation. When the hydrogen pressure dropped below 2 MPa, hydrogen gas was introduced to a pressure of 3-4 MPa until the hydrogen pressure no longer decreased. After the reaction was complete, no byproduct isopropanol was detected in the mother liquor. The remaining ketone and water were removed under reduced pressure to obtain 22.34 g of the final antioxidant product. The liquid chromatography purity (HPLC) was 99.1% (after deducting the ketone content), and the product yield based on 4-aminodiphenylamine was 98.73%.

[0075] Application Example 3

[0076] 19.9 g of 4,4-diaminodiphenylamine, 46.4 g of acetone, and 3 g of the catalyst from Example 2 were added to a 100 mL high-pressure reactor. Hydrogen gas was then introduced to a pressure of 3-4 MPa, and the reaction temperature was controlled at 120 °C to carry out ketone-amine dehydration condensation. When the hydrogen pressure dropped below 2 MPa, hydrogen gas was introduced to a pressure of 3-4 MPa until the hydrogen pressure no longer decreased. After the reaction was completed, no byproduct isopropanol was detected in the mother liquor. The remaining ketone and water were removed under reduced pressure to obtain 27.81 g of the final antioxidant product. The liquid chromatography purity (HPLC) was 99.5% (after deducting the ketone content), and the product yield, based on 4,4-diaminodiphenylamine, was 98.27%.

[0077] Application Example 4

[0078] 10 g of 4,4-diaminodiphenylamine, 50 g of methyl isobutyl ketone, and 3 g of the catalyst from Example 2 were added to a 100 mL high-pressure reactor. Hydrogen gas was then introduced to 3-4 MPa, and the reaction temperature was controlled at 120 °C to carry out ketone-amine dehydration condensation. When the hydrogen pressure dropped below 2 MPa, hydrogen gas was introduced to 3-4 MPa until the hydrogen pressure no longer decreased. After the reaction was completed, no byproduct methyl isobutyl methanol was detected in the mother liquor. The remaining ketone and water were removed under reduced pressure to obtain 18.18 g of the final antioxidant product. The liquid chromatography purity (HPLC) was 99.0% (after deducting the ketone content), and the product yield, based on 4,4-diaminodiphenylamine, was 99.07%.

[0079] Application Example 5

[0080] The antioxidant product was prepared according to the conditions of Application Example 1, except that the catalyst in Application Example 1 was reused. The results are shown in Table 1 below:

[0081] Table 1

[0082] Application Example 6

[0083] 18.4 g of 4-aminodiphenylamine, 50 g of methyl isobutyl ketone, and 3 g of different catalysts were added to a 100 mL high-pressure reactor. Hydrogen gas was then introduced to a pressure of 3-4 MPa, and the reaction temperature was controlled at 120 °C to carry out ketone-amine dehydration condensation. When the hydrogen pressure dropped below 2 MPa, hydrogen gas was introduced to a pressure of 3-4 MPa until the hydrogen pressure no longer decreased. After the reaction was complete, the alcohol content in the mother liquor was measured. Then, the alcohol, ketone, and water were removed under reduced pressure to obtain the final antioxidant product. The catalysts used and the product details are shown in Table 2 below.

[0084] Table 2

[0085] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been shown above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments 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. A method for preparing a catalyst for a dehydration condensation reduction reaction, comprising the following steps: (1) Spread activated carbon evenly in a fixed bed, and then continuously pass a mixed solution of copper nitrate, zinc nitrate and zirconium nitrate into the fixed bed so that the mixed solution is in full contact with the activated carbon layer; (2) The activated carbon that has been in full contact with the mixed solution is calcined to obtain activated carbon loaded with copper oxide-zinc oxide-zirconia; (3) Disperse the activated carbon loaded with copper oxide-zinc oxide-zirconia into an organic solvent, then add a sulfiding agent to carry out a sulfidation reaction. After the reaction, filter, wash and dry to obtain a catalyst for dehydration condensation reduction reaction.

2. The preparation method according to claim 1, wherein step (1) includes at least one of the following conditions: a. The specific surface area of ​​activated carbon is 1250-1350㎡ / g; b. The thickness of the activated carbon layer is 1.3-1.8 cm; c. The flow rate of the mixed solution is 1-10 ml / min; d. In the mixed solution, the concentration of copper nitrate is 1-5 g / 100 ml, the concentration of zinc nitrate is 3-7 g / 100 ml, and the concentration of zirconium nitrate is 1-5 g / 100 ml; e. The temperature when the mixed solution comes into contact with the activated carbon layer is 25-45℃, and the contact time is 0.5-2h.

3. According to the preparation method of claim 1 or 2, in step (2), the calcination is carried out in air, the calcination temperature is 400-800℃, and the calcination time is 2-6h.

4. The preparation method according to claim 1, wherein step (3) includes at least one of the following conditions: a. The vulcanizing agent is at least one selected from dimethyl sulfide, dodecyl mercaptan, dimethyl sulfoxide, diphenyl sulfide, and diphenyl disulfide; b. The organic solvent is an alcohol; c. The mass ratio of activated carbon loaded with copper oxide-zinc oxide-zirconia to sulfiding agent is 5:0.1-1.

5. In the preparation method according to claim 1 or 4, in step (3), the vulcanizing agent is a mixture of diphenyl sulfide and diphenyl disulfide.

6. In the preparation method according to claim 1 or 4, in step (3), the organic solvent is methanol, ethanol or isopropanol.

7. According to the preparation method of claim 1 or 4, in step (3), the vulcanizing agent is added dropwise for 2-5 minutes; 8. According to the preparation method of claim 7, in step (3), the temperature of adding the sulfiding agent is 25-45℃, and the reaction is kept at the temperature for 0.5-2h after the addition is complete.

9. A catalyst prepared according to any one of claims 1-8 for a dehydration condensation reduction reaction.

10. The use of the catalyst according to claim 9 in the dehydration condensation reduction reaction of aldehydes and amines or the dehydration condensation reduction reaction of ketones and amines.

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