The invention relates to a method for catalytically synthesizing N, N, Napos; , Napos, Napos; catalyst for 2-tetramethylethylenediamine as well as preparation method and application of catalyst

Abstract

The invention relates to the technical field of organic synthesis, in particular to a catalyst for catalytic synthesis of N, N, N ', N'-tetramethylethylenediamine as well as a preparation method and application of the catalyst. The composition of the copper-nickel-cerium-zirconium catalyst is CuO-NiO-CeO2-ZrO2, and the copper-nickel-cerium-zirconium catalyst is Wherein the molar ratio of CuO to NiO to CeO2 to ZrO2 is (60 to 65): (5 to 25): (10 to 25): (1 to 10). The copper-nickel-cerium-zirconium catalyst provided by the invention can efficiently catalyze dimethylamine and ethylene glycol to react to prepare N, N, N ', N'-tetramethylethylenediamine, the conversion rate of ethylene glycol can reach 99%, and the selectivity of N, N, N ', N'-tetramethylethylenediamine can reach 90%.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic synthesis, in particular to a catalyst for catalytic synthesis of N, N, N', N'-tetramethylethylenediamine and a preparation method and application thereof. BACKGROUND

[0002] The information disclosed in this BACKGROUND section is only for the purpose of increasing the understanding of the background of the present application and therefore it should not be taken as an acknowledgement or any form of suggestion that it forms prior art with respect to any country.

[0003] N, N, N', N'-tetramethylethylenediamine is a colorless transparent liquid, slightly ammonia smell, miscible with water, and can be miscible in ethanol and most organic solvents, which is an important organic intermediate, mainly used as biochemical reagent, epoxy resin crosslinking agent, and intermediate for synthesis of quaternary amine compounds.

[0004] At present, the methods for preparing N, N, N', N'-tetramethylethylenediamine mainly include the following three kinds: one is to react ethylenediamine with formic acid and formaldehyde as methylating reagent, formaldehyde provides methyl, formic acid provides hydrogen proton and acts as reducing agent; this method has mild reaction conditions, convenient operation, high conversion rate and single product, however, formic acid is oxidized to be removed, a large amount of carbon dioxide gas is released, and the polyoxymethylene is also depolymerized to release formaldehyde gas, which pollutes the environment. The second is to react ethylenediamine with methanol as methylating reagent, which is generally reacted in a fixed bed, and N, N, N', N'-tetramethylethylenediamine is formed by dehydration under the catalysis of metal supported catalyst, the raw material is easy to obtain and clean, however, the selectivity is poor and the by-products are many in the reaction process. The third is to react with dimethylamine as methylating reagent in the presence of N-propylmorpholine, however, there are many by-products in this reaction, and hydrogen chloride gas is generated, which pollutes the environment.

[0005] N, N, N', N'-tetramethylethylenediamine is prepared by reacting dimethylamine and ethylene glycol, the raw material is easy to obtain, friendly to the environment, and the types of by-products are few, which can be theoretically produced industrially, however, the non-noble metal catalysts reported at present have the problems of low conversion rate and selectivity of catalysis, which greatly limits the industrial application. SUMMARY

[0006] In order to overcome the above problems, the present application provides a catalyst for catalytic synthesis of N, N, N', N'-tetramethylethylenediamine and a preparation method and application thereof.

[0007] In order to achieve the above technical purposes, the present application adopts the following technical solutions: In a first aspect of the present application, a copper-nickel-cerium-zirconium catalyst is provided, the composition of the catalyst is CuO-NiO-CeO2-ZrO2. The molar ratio of CuO, NiO, CeO2 and ZrO2 is (60-65):(5-25):(10-25):(1-10).

[0008] In a second aspect of the present application, a preparation method of the copper-nickel-cerium-zirconium catalyst is provided, comprising the following steps: (1) adding a nickel precursor solution into the cerium precursor solution, adjusting the pH value of the mixed solution to 7-13 by adding a precipitator, and performing first ripening; (2) adding a copper precursor solution into the mixed solution after the first ripening, adjusting the pH value of the mixed solution to 7-13 by adding a precipitator, and performing second ripening; (3) adding a zirconium precursor solution into the mixed solution after the second ripening, adjusting the pH value of the mixed solution to 7-13 by adding a precipitator, and performing third ripening; (4) collecting the solid after filtering the mixed solution after the third ripening, and obtaining the copper-nickel-cerium-zirconium catalyst after washing, drying, grinding and heat treatment.

[0009] In one or more embodiments, in step (1), the cerium precursor includes one or more of cerium nitrate and cerium chloride.

[0010] In one or more embodiments, in step (1), the concentration of the cerium precursor solution is 0.8-1.2 mol / L, and preferably 1.0 mol / L.

[0011] In one or more embodiments, in step (1), the nickel precursor includes one or more of nickel nitrate, nickel chloride, nickel acetate and nickel sulfate.

[0012] In one or more embodiments, in step (1), the concentration of the nickel precursor solution is 0.8-1.2 mol / L, and preferably 1.0 mol / L.

[0013] In one or more embodiments, in steps (1)-(3), the precipitator includes one or more of ammonia, sodium carbonate, sodium bicarbonate, ammonium bicarbonate or sodium hydroxide; and preferably sodium carbonate.

[0014] In one or more embodiments, in step (2), the copper precursor includes one or more of copper acetate, copper nitrate, copper chloride and copper oxalate.

[0015] In one or more embodiments, in step (2), the concentration of the copper precursor solution is 0.8-1.2 mol / L, and preferably 1.0 mol / L.

[0016] In one or more embodiments, in step (3), the zirconium precursor includes one or more of zirconium acetate, zirconium nitrate, zirconium chloride and zirconium oxalate.

[0017] In one or more embodiments, in step (3), the concentration of the zirconium precursor solution is 0.8~1.2 mol / L, preferably 1.0 mol / L.

[0018] In one or more embodiments, during steps (1) to (3), the temperature is 50 to 90 °C and the time is 0.5 to 2 h during the first, second, and third maturation processes. The temperature and pH of the solution are kept constant during the maturation process.

[0019] In one or more embodiments, in steps (1) to (3), the molar ratio of copper precursor, nickel precursor, cerium precursor and zirconium precursor is (60~65):(5~25):(10~25):(1~10).

[0020] In one or more embodiments, in step (4), the heat treatment temperature is 400~600 ℃ and the heat treatment time is 0.5~12 h.

[0021] A third aspect of the present invention provides the application of the copper-nickel-cerium-zirconium catalyst described in the first aspect or the copper-nickel-cerium-zirconium catalyst prepared by the preparation method described in the second aspect in the catalytic reaction of dimethylamine and ethylene glycol to prepare N,N,N',N'-tetramethylethylenediamine.

[0022] A fourth aspect of the present invention provides a method for synthesizing N,N,N',N'-tetramethylethylenediamine, wherein dimethylamine and ethylene glycol are used as raw materials, hydrogen is introduced, and N,N,N',N'-tetramethylethylenediamine is synthesized by reaction under the catalysis of the copper-nickel-cerium-zirconium catalyst described in the first aspect or the copper-nickel-cerium-zirconium catalyst prepared by the preparation method described in the second aspect.

[0023] In one or more embodiments, the reaction temperature for synthesizing N,N,N',N'-tetramethylethylenediamine is 200~250°C.

[0024] The beneficial effects of this invention are as follows: (1) The copper-nickel-cerium-zirconium catalyst provided by the present invention can efficiently catalyze the reaction of dimethylamine and ethylene glycol to prepare N,N,N',N'-tetramethylethylenediamine. The conversion rate of ethylene glycol can reach 99%, and the selectivity of N,N,N',N'-tetramethylethylenediamine can reach 90%.

[0025] (2) The copper-nickel-cerium-zirconium catalyst provided by this invention improves the conversion rate of ethylene glycol and the selectivity of N,N,N',N'-tetramethylethylenediamine from three aspects: functional complementarity, electronic optimization, and structural temperature. Regarding functional complementarity: the reaction of dimethylamine and ethylene glycol to synthesize N,N,N',N'-tetramethylethylenediamine mainly includes three steps. First, ethylene glycol undergoes dehydrogenation at the metal site to generate an aldehyde (hydroxyacetaldehyde) and hydrogen atoms. Second, the generated aldehyde undergoes nucleophilic addition-dehydration with dimethylamine to generate an imine intermediate. Third, the imine intermediate is reduced by hydrogen atoms generated by ethylene glycol to synthesize N,N,N',N'-tetramethylethylenediamine. Cu and Ni in the copper-nickel-cerium-zirconium catalyst can not only serve as excellent dehydrogenation catalysts to accelerate the dehydrogenation of ethylene glycol, but also serve as good hydrogenation catalysts to efficiently promote the hydrogenation of imine. Zr and Ce, as strong Lewis acids, can very effectively provide acidic sites to activate the carbonyl group of aldehydes and promote nucleophilic addition-dehydration. Regarding electronic optimization, metals with lower electronegativity (Ce and Zr) can transfer electrons to metals with higher electronegativity (Cu and Ni), altering the electron density on the latter's surface. This electronic modulation can "fine-tune" the adsorption strength of active sites for reactants, intermediates, and products. Excessive adsorption can lead to catalyst poisoning; insufficient adsorption cannot effectively activate molecules. Multi-metal systems can find an optimal adsorption strength through electronic effects, thereby accelerating the reaction rate. Regarding structural stability, the presence of one metal in a copper-nickel-cerium-zirconium catalyst can act as a "structural aid" for another metal, preventing the sintering and aggregation of active components, allowing them to exist in a smaller, more dispersed form, thus exposing more active sites. Attached Figure Description

[0026] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0027] Figure 1 The images show the CO-TPR spectra of the catalysts prepared in Examples 1, 1, 2, 3, and 5; where a is Example 1, b is Comparative Example 3, c is Comparative Example 1, d is Comparative Example 5, and e is Comparative Example 2. Figure 2 The catalytic effects of the catalysts prepared in Examples 1, 14-16 are shown. Figure 3 The value represents the lifespan of the catalyst prepared in Example 1. Detailed Implementation

[0028] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0029] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0030] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0031] Example 1 Preparation of copper-nickel-cerium-zirconium catalysts: (1) Add 1.5 mL of 1.0 mol / L nickel nitrate solution to 6.2 mL of 1.0 mol / L cerium nitrate solution, add sodium carbonate as precipitant to adjust the pH of the mixed solution to 8; carry out the first aging; the temperature of the first aging is 60 ℃ and the time is 0.5 h; the beaker is covered during the aging process to prevent excessive evaporation of water.

[0032] (2) Add 1.8 mL of 1.0 mol / L copper nitrate solution to the mixed solution after the first maturation, and add sodium carbonate as a precipitant to adjust the pH of the mixed solution to 8; carry out the second maturation; the temperature of the second maturation is 60 ℃ and the time is 0.5 h; the beaker is covered during the maturation process to prevent excessive evaporation of water.

[0033] (3) Add 0.5 mL of 1.0 mol / L zirconium nitrate solution to the mixed solution after the second aging, and add sodium carbonate as a precipitant to adjust the pH of the mixed solution to 8; carry out the third aging; the temperature of the third aging is 60 ℃ and the time is 0.75 h; the beaker is covered during the aging process to prevent excessive evaporation of water.

[0034] (4) After filtering the mixed solution after the third maturation, the solid was collected, washed with deionized water 3 to 5 times, dried at 80°C, ground and heat-treated to obtain the copper-nickel-cerium-zirconium catalyst; the heat treatment temperature was 500°C and the heat treatment time was 3h.

[0035] Example 2 Compared with Example 1, the molar ratio of copper precursor, nickel precursor, cerium precursor and zirconium precursor was adjusted, and the other methods were exactly the same as in Example 1.

[0036] The volume of cerium nitrate solution is 6.2 mL of 1.0 mol / L; The volume of nickel nitrate solution is 1.0 mL of 1.0 mol / L. The volume of copper nitrate solution is 2.1 mL of 1.0 mol / L; The volume of zirconium nitrate solution is 0.7 mL of 1.0 mol / L.

[0037] Example 3 Compared with Example 1, the molar ratio of copper precursor, nickel precursor, cerium precursor and zirconium precursor was adjusted, and the other methods were exactly the same as in Example 1.

[0038] The volume of cerium nitrate solution is 6.2 mL of 1.0 mol / L; The volume of nickel nitrate solution is 2.0 mL of 1.0 mol / L; The volume of copper nitrate solution is 1.5 mL of 1.0 mol / L; The volume of zirconium nitrate solution is 0.3 mL of 1.0 mol / L.

[0039] Example 4 Compared with Example 1, the molar ratio of copper precursor, nickel precursor, cerium precursor and zirconium precursor was adjusted, and the other methods were exactly the same as in Example 1.

[0040] The volume of cerium nitrate solution is 6.2 mL of 1.0 mol / L; The volume of nickel nitrate solution is 2.5 mL of 1.0 mol / L; The volume of copper nitrate solution is 1.2 mL of 1.0 mol / L; The volume of zirconium nitrate solution is 0.1 mL of 1.0 mol / L.

[0041] Comparative Example 1 Compared to Example 1, the catalyst contains only copper and nickel.

[0042] The volume of copper nitrate solution is 7.0 mL of 1.0 mol / L; The volume of nickel nitrate solution is 3.0 mL of 1.0 mol / L; The other methods are exactly the same as in Example 1.

[0043] Comparative Example 2 Compared to Example 1, the catalyst contains only cerium and zirconium.

[0044] The volume of cerium nitrate solution is 2.5 mL of 1.0 mol / L; The volume of zirconium nitrate solution is 2.5 mL of 1.0 mol / L; The other methods are exactly the same as in Example 1.

[0045] Comparative Example 3 Compared to Example 1, the catalyst contains only copper, nickel, and cerium.

[0046] The volume of copper nitrate solution is 5.5 mL of 1.0 mol / L; The volume of nickel nitrate solution is 2.3 mL of 1.0 mol / L; The volume of cerium nitrate solution is 2.2 mL of 1.0 mol / L. The other methods are exactly the same as in Example 1.

[0047] Comparative Example 4 Compared to Example 1, the catalyst contains only copper, nickel, and zirconium.

[0048] The volume of copper nitrate solution is 6.5 mL of 1.0 mol / L; The volume of nickel nitrate solution is 3.0 mL of 1.0 mol / L; The volume of zirconium nitrate solution is 0.5 mL of 1.0 mol / L; The other methods are exactly the same as in Example 1.

[0049] Comparative Example 5 Compared to Example 1, the catalyst contains only copper, cerium, and zirconium.

[0050] The volume of copper nitrate solution is 6.5 mL of 1.0 mol / L; The volume of cerium nitrate solution is 2.5 mL of 1.0 mol / L; The volume of zirconium nitrate solution is 1.0 mL of 1.0 mol / L; The other methods are exactly the same as in Example 1.

[0051] Comparative Example 6 Compared to Example 1, the catalyst contains only nickel, cerium, and zirconium.

[0052] The volume of nickel nitrate solution is 4.0 mL of 1.0 mol / L; The volume of cerium nitrate solution is 3.0 mL of 1.0 mol / L; The volume of zirconium nitrate solution is 3.0 mL of 1.0 mol / L; The other methods are exactly the same as in Example 1.

[0053] Experimental Example 1 The catalyst powders prepared in Examples 1-4 and Comparative Examples 1-6 were pressed into tablets and sieved to obtain catalyst particles of 10-20 mesh. 21.3 g of the catalyst was weighed and loaded into a stainless steel reactor, which was placed in an electric heating furnace. Using dimethylamine and ethylene glycol as raw materials, hydrogen gas was introduced, the hydrogen volume concentration in the reaction gas was 100%, the reaction temperature was 230 °C, and the ethylenediamine volume hourly space velocity was 0.3 h⁻¹. -1 The molar ratio of ethylene glycol to dimethylamine was 4:1, and the hydrogen flow rate was 60 mL / min. The conversion rate of ethylene glycol and the selectivity of N,N,N',N'-tetramethylethylenediamine were used as the activity indicators of the catalyst.

[0054] The catalytic effects of the catalysts prepared in Examples 1-4 and Comparative Examples 1-6 are shown in Table 1.

[0055] Table 1 Catalytic effects of the catalysts prepared in Examples 1-4 and Comparative Examples 1-6

[0056] As can be seen from Table 1, the activity of the CuNiZrCe quaternary catalyst is significantly better than that of the ternary or binary catalysts. Copper-nickel-cerium-zirconium catalysts improve the conversion rate of ethylene glycol and the selectivity of N,N,N',N'-tetramethylethylenediamine mainly through three aspects: functional complementarity, electronic optimization, and structural temperature. Regarding functional complementarity: the synthesis of N,N,N',N'-tetramethylethylenediamine from dimethylamine and ethylene glycol mainly involves three steps. First, ethylene glycol undergoes dehydrogenation at a metal site to generate an aldehyde (hydroxyacetaldehyde) and hydrogen atoms. Second, the generated aldehyde undergoes nucleophilic addition-dehydration with dimethylamine to generate an imine intermediate. Third, the imine intermediate is reduced by hydrogen atoms generated from ethylene glycol to synthesize N,N,N',N'-tetramethylethylenediamine. Cu and Ni in the copper-nickel-cerium-zirconium catalyst not only serve as excellent dehydrogenation catalysts, accelerating the dehydrogenation of ethylene glycol, but also as good hydrogenation catalysts, efficiently promoting the hydrogenation of imines. Zr and Ce, as strong Lewis acids, can effectively provide acidic sites to activate the carbonyl group of the aldehyde, promoting nucleophilic addition-dehydration. Regarding electronic optimization, metals with lower electronegativity (Ce and Zr) can transfer electrons to metals with higher electronegativity (Cu and Ni), altering the electron density on the latter's surface. This electronic modulation can "fine-tune" the adsorption strength of active sites for reactants, intermediates, and products. Excessive adsorption can lead to catalyst poisoning; insufficient adsorption cannot effectively activate molecules. Multi-metal systems can find an optimal adsorption strength through electronic effects, thereby accelerating the reaction rate. Regarding structural stability, the presence of one metal in a copper-nickel-cerium-zirconium catalyst can act as a "structural aid" for another metal, preventing the sintering and aggregation of active components, allowing them to exist in a smaller, more dispersed form, thus exposing more active sites.

[0057] Figure 1 The CO-TPR spectra of the catalysts prepared in Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 5 are shown below. Figure 1 The results show that the optimal quaternary catalyst prepared by adding Ce and Zr to Cu and Ni has a lower CO reduction peak compared with ternary or binary catalysts, which can enhance the surface redox ability of the catalyst. This further verifies that under the catalytic action of the optimal catalyst, ethylene glycol and dimethylamine can react at a lower reaction temperature.

[0058] Example 5 Compared with Example 1, the temperature of the first, second, and third maturation processes in the preparation of the copper-nickel-cerium-zirconium catalyst was adjusted to 50 °C, while the other methods were exactly the same as in Example 1.

[0059] Example 6 Compared with Example 1, the temperature of the first, second, and third maturation processes in the preparation of the copper-nickel-cerium-zirconium catalyst was adjusted to 70 °C, while the other methods were exactly the same as in Example 1.

[0060] Example 7 Compared with Example 1, the temperature of the first, second, and third maturation processes in the preparation of the copper-nickel-cerium-zirconium catalyst was adjusted to 80 °C, while the other methods were exactly the same as in Example 1.

[0061] Example 8 Compared with Example 1, the temperature of the first, second, and third maturation processes in the preparation of the copper-nickel-cerium-zirconium catalyst was adjusted to 90 °C, while the other methods were exactly the same as in Example 1.

[0062] Example 9 Compared with Example 1, the pH value of the mixed solution was adjusted to 7 after adding a precipitant in steps (1), (2) and (3) of the preparation process of the copper-nickel-cerium-zirconium catalyst. The other methods were exactly the same as in Example 1.

[0063] Example 10 Compared with Example 1, the pH value of the mixed solution was adjusted to 9 after adding a precipitant in steps (1), (2) and (3) of the preparation process of the copper-nickel-cerium-zirconium catalyst. The other methods were exactly the same as in Example 1.

[0064] Experiment Example 2 The catalytic effects of the catalysts prepared in Examples 1, 5-10 were tested using the same testing method as in Experiment 1, and the results are shown in Table 2.

[0065] Table 2 Catalytic effects of the catalysts prepared in Examples 1, 5-10

[0066] As can be seen from Table 2, when the precipitation pH is 7, some active components are not effectively precipitated, resulting in a lower than actual active component of the catalyst, which reduces the catalyst activity and selectivity. When the pH is 9, the precursor settles faster, and agglomeration occurs, which reduces the catalyst activity. When the maturation temperature is 60 °C, it is conducive to the formation of smaller particle size and pore size of the catalyst, which helps to improve the catalyst activity.

[0067] Example 11 Compared with Example 1, the time for the second and third maturation in steps (2) and (3) of the preparation process of copper-nickel-cerium-zirconium catalyst was adjusted to 0.5 h, and the other methods were exactly the same as in Example 1.

[0068] Example 12 Compared with Example 1, the second maturation time in step (2) of the preparation process of copper-nickel-cerium-zirconium catalyst was adjusted to 0.75 h, while the other methods were exactly the same as in Example 1.

[0069] Example 13 Compared with Example 1, the time for the first and second maturation in step (1) of the preparation process of copper-nickel-cerium-zirconium catalyst was adjusted to 0.75 h, while the other methods were exactly the same as in Example 1.

[0070] Experimental Example 3 The catalytic effects of the catalysts prepared in Examples 1, 11-13 were tested using the same testing method as in Experiment 1, and the results are shown in Table 3.

[0071] Table 3 Catalytic effects of the catalysts prepared in Examples 1, 11-13

[0072] As can be seen from Table 3, the maturation time of each precursor has a relatively small impact on the activity and selectivity of the catalyst.

[0073] Example 14 Compared with Example 1, the temperature of the heat treatment in step (4) was adjusted to 300 °C, and the other methods were exactly the same as in Example 1.

[0074] Example 15 Compared with Example 1, the temperature of the heat treatment in step (4) was adjusted to 400 °C, and the other methods were exactly the same as in Example 1.

[0075] Example 16 Compared with Example 1, the temperature of the heat treatment in step (4) was adjusted to 600 °C, and the other methods were exactly the same as in Example 1.

[0076] Experiment Example 4 The catalytic effects of the catalysts prepared in Examples 1, 14-16 were tested using the same testing method as in Experimental Example 1, and the results are as follows: Figure 2 As shown in Table 4.

[0077] Table 4 Catalytic effects of the catalysts prepared in Examples 1, 14-16

[0078] from Figure 2 As shown in Table 4, the heat treatment temperature affects the catalyst activity and selectivity. The catalyst activity first increases and then decreases with the increase of heat treatment temperature. This may be because at lower heat treatment temperatures, some or a small amount of precursors may not be completely decomposed, leading to a decrease in the active components and a weaker interaction between components. At high temperatures, the active components of the catalyst may sinter, resulting in a decrease in the catalyst specific surface area and the dispersion of the active components, which in turn leads to a decrease in catalyst activity.

[0079] Experimental Example 5 The lifespan of the catalyst prepared in Example 1 was tested using the same test method as in Experimental Example 1, and the results are as follows: Figure 3 As shown, from Figure 3 As can be seen from the examples, the activity and selectivity of the copper-nickel-cerium-zirconium catalyst prepared in the examples did not decrease significantly during the test, and the catalyst has good catalytic activity and stability.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A copper nickel cerium zirconium catalyst characterized in that, The catalyst is composed of CuO-NiO-CeO2-ZrO2; The molar ratio of CuO, NiO, CeO2 and ZrO2 is (60-65):(5-25):(10-25):(1-10).

2. The process for the preparation of the copper nickel cerium zirconium catalyst according to claim 1, characterized in that, The method comprises the following steps: (1) adding a nickel precursor solution to a cerium precursor solution, adjusting the pH value of the mixed solution to 7-13 by adding a precipitator, and performing first ripening; (2) adding a copper precursor solution to the mixed solution after the first ripening, adjusting the pH value of the mixed solution to 7-13 by adding a precipitator, and performing second ripening; (3) adding a zirconium precursor solution to the mixed solution after the second ripening, adjusting the pH value of the mixed solution to 7-13 by adding a precipitator, and performing third ripening; (4) collecting the solid after filtering the mixed solution after the third ripening, and obtaining the copper-nickel-cerium-zirconium catalyst after washing, drying, grinding and heat treatment.

3. The production method according to claim 1, wherein In step (1), the cerium precursor comprises one or more of cerium nitrate and cerium chloride; The concentration of the cerium precursor solution is 0.8-1.2 mol / L; The nickel precursor comprises one or more of nickel nitrate, nickel chloride, nickel acetate and nickel sulfate; The concentration of the nickel precursor solution is 0.8-1.2 mol / L.

4. The production method according to claim 1, wherein The precipitator in steps (1)-(3) comprises one or more of ammonia, sodium carbonate, sodium bicarbonate, ammonium bicarbonate or sodium hydroxide.

5. The production method according to claim 1, wherein In step (2), the copper precursor comprises one or more of copper acetate, copper nitrate, copper chloride and copper oxalate; The concentration of the copper precursor solution is 0.8-1.2 mol / L; In step (3), the zirconium precursor comprises one or more of zirconium acetate, zirconium nitrate, zirconium chloride and zirconium oxalate; The concentration of the zirconium precursor solution is 0.8-1.2 mol / L, preferably 1.0 mol / L.

6. The production method according to claim 1, wherein In steps (1)-(3), the temperature during the first ripening, the second ripening and the third ripening is 50-90 ℃, and the time is 0.5-2 h.

7. The production method according to claim 1, wherein In steps (1)-(3), the molar ratio of the copper precursor, the nickel precursor, the cerium precursor and the zirconium precursor is (60-65):(5-25):(10-25):(1-10).

8. The production method according to claim 1, wherein In step (4), the temperature of the heat treatment is 400-600 ℃, and the time of the heat treatment is 0.5-12 h.

9. The use of the copper-nickel-cerium-zirconium catalyst of claim 1 or the copper-nickel-cerium-zirconium catalyst prepared by the preparation method of any one of claims 2-8 in catalyzing the reaction of dimethylamine and ethylene glycol to prepare N,N,N',N'-tetramethylethylenediamine.

10. A method of synthesizing N,N,N',N'-tetramethylethylenediamine, characterized in that, N,N,N',N'-tetramethylethylenediamine is synthesized by inputting hydrogen under the catalysis of the copper-nickel-cerium-zirconium catalyst of claim 1 or the copper-nickel-cerium-zirconium catalyst prepared by the preparation method of any one of claims 2-8.

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