Copper-lanthanum-based catalyst as well as preparation method and application thereof

Abstract

The invention discloses a copper-lanthanum-based catalyst as well as a preparation method and application thereof. The copper-lanthanum-based catalyst comprises a silicon-based carrier and an active component loaded on the silicon-based carrier, the active components comprise copper and lanthanum. According to the preparation method of the copper-lanthanum-based catalyst provided by the invention, the copper-lanthanum-based catalyst is applied to a reaction for preparing fatty nitrile through fatty alcohol dehydrogenation ammoniation, the catalyst prepared by the method can remarkably improve the production efficiency of the fatty nitrile, the stability of the catalyst is obviously improved, and the service life of the catalyst is obviously prolonged.

Description

Technical Field

[0001] The present application relates to a copper-lanthanum-based catalyst, a preparation method and an application thereof, belonging to the technical field of bioenergy chemical engineering. Background Art

[0002] Fatty nitriles are an important class of nitrogen-containing chemical raw materials and synthetic intermediates, which can be used in multiple fields such as pharmaceutical chemistry, analytical chemistry, organic chemistry, polymer chemistry, etc., and the market demand increases year by year. Generally, fatty nitriles can be obtained by methods such as nucleophilic cyanation of alkyl halides, Wittig reaction, amine dehydrogenation, alcohol ammoxidation, carboxylic acid ammoniation, aldehyde oxime dehydration, alkane ammoxidation (for industrial production of acetonitrile), etc., but they face problems such as the use of a large amount of organic solvents, difficulty in recovering heterogeneous catalysts, and by-production of highly toxic hydrocyanic acid. In recent years, with the maturity of new industrial production routes of ethanol and higher alcohols, the route of gas-phase dehydrogenation ammoniation of fatty alcohols to synthesize fatty nitriles has gradually attracted attention, with advantages such as easy control of reaction heat, high selectivity, and co-production of hydrogen.

[0003] The reaction of dehydrogenation ammoniation of fatty alcohols to fatty nitriles belongs to a metal-acid dual-site cooperative catalytic reaction network, in which the metal component usually selects transition metals in the fourth period such as Cu, Ni, Co, Cr, etc., and the carriers focus on Al 2 O 3 、ZrO 2 、molecular sieves and other acidic oxides. Regulating the metal active component is a classic strategy for optimizing the metal-support interaction and modulating the catalyst activity and target product selectivity. For example, the National University of Singapore reported the use of Cu and Ni bimetallic components supported on Al 2 O 3 carriers to catalyze the dehydrogenation ammoniation of butanol to butyronitrile, and its activity is significantly higher than that of Cu-Al 2 O 3 and Ni-Al 2 O 3 (ACS Catal. 2019, 9, 6681-6691). Hebei University of Technology reported the use of Co and Ni bimetallic components supported on Al 2 O 3The dehydrogenative amination of ethanol by a catalyst can achieve an initial acetonitrile selectivity of 92%, but the acetonitrile selectivity gradually decreases with the progress of the reaction (Cata. Commun., 2009, 10, 1454 - 1458). The National University of Chemical Technology of Ukraine reported that the dehydrogenative amination of ethanol using a composite oxide composed of Cu, Zn, Zr, Al, and Ca can achieve an acetonitrile single - pass yield of 92% (Russ. J. Appl. Chem., 2016, 89, 414 - 420). Currently, although the reaction activity of the dehydrogenative amination of fatty alcohols to fatty nitriles can be improved by component regulation, the problem of short catalytic life caused by catalyst sintering deactivation and carbon deposition cannot be overcome, limiting its large - scale application. Summary of the Invention

[0004] The object of the present invention is to provide the preparation and application of a copper - lanthanum - based catalyst. This method has the advantages of simple operation, low catalyst cost, economic practicality, high efficiency in producing fatty nitriles, low carbon deposition degree, long catalytic life, etc.

[0005] According to one aspect of the present application, a copper - lanthanum - based catalyst is provided. The copper - lanthanum - based catalyst includes a silicon - based carrier and an active component supported on the silicon - based carrier;

[0006] The active component includes copper and lanthanum;

[0007] The particle size of the copper - lanthanum - based catalyst is 2 - 15 nm.

[0008] Optionally, the metal nanoparticles of the copper - lanthanum - based catalyst are less than 15 nm.

[0009] Optionally, in the copper - lanthanum - based catalyst, the loading amount of copper is 1 wt% - 40 wt%.

[0010] Optionally, in the copper - lanthanum - based catalyst, the loading amount of copper independently selects any value from 1 wt%, 2 wt%, 5 wt%, 8 wt%, 10 wt%, 12 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt% or the range value between any two of the above.

[0011] Optionally, in the copper - lanthanum - based catalyst, the loading amount of lanthanum is 0.1 wt% - 10 wt%.

[0012] Optionally, in the copper - lanthanum - based catalyst, the loading amount of lanthanum independently selects any value from 0.1 wt%, 0.2 wt%, 0.5 wt%, 1 wt%, 2 wt%, 4 wt%, 6 wt%, 8 wt%, 10 wt% or the range value between any two of the above.

[0013] According to another aspect of the present application, there is provided a method for preparing the copper-lanthanum-based catalyst described above, and the preparation method includes:

[0014] Immerse the silicon-based support in a mixture containing copper salt and lanthanum salt, stand, dry I, calcine I, and reduce I to obtain the copper-lanthanum-based catalyst;

[0015] Alternatively, adopt the co-precipitation method, and age, dry II, calcine II, and reduce II a mixture II containing copper salt, lanthanum salt, precipitant, and silicon-based support to obtain the copper-lanthanum-based catalyst.

[0016] Optionally, the copper salt is selected from at least one of copper nitrate, copper chloride, copper acetate, copper sulfate, and basic copper sulfate.

[0017] Optionally, the lanthanum salt is selected from at least one of lanthanum nitrate, lanthanum chloride, and lanthanum sulfate.

[0018] Optionally, the silicon-based support is selected from at least one of mesoporous silica, silica sol, white carbon black, activated silica, metakaolin, and macroporous silica gel.

[0019] Optionally, the precipitant is selected from at least one of ammonia water, sodium carbonate, sodium bicarbonate, urea, and ammonium carbonate.

[0020] Optionally, the standing time is 2 to 24 h.

[0021] Optionally, the standing time is independently selected from any value of 2 h, 4 h, 6 h, 8 h, 12 h, 16 h, 20 h, 24 h or the range value between any two of the above.

[0022] Optionally, the temperatures of drying I and drying II are independently selected from 80 to 150 °C, and the times of drying I and drying II are independently selected from 1 to 48 h.

[0023] Optionally, the temperatures of drying I and drying II are independently selected from any value of 80 °C, 90 °C, 100 °C, 110 °C, 120 °C, 130 °C, 140 °C, 150 °C or the range value between any two of the above.

[0024] Optionally, the times of drying I and drying II are independently selected from any value of 1 h, 2 h, 4 h, 8 h, 12 h, 16 h, 20 h, 24 h, 36 h, 48 h or the range value between any two of the above.

[0025] Optionally, the temperatures of calcining I and calcining II are independently selected from 300 to 700 °C, and the times of calcining I and calcining II are independently selected from 2 to 48 h.

[0026] Optionally, the temperatures of the first calcination and the second calcination are independently selected from any value of 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 700°C or a range value between any two of the above.

[0027] Optionally, the times of the first calcination and the second calcination are independently selected from any value of 2 h, 4 h, 8 h, 12 h, 16 h, 20 h, 24 h, 36 h, 48 h or a range value between any two of the above.

[0028] Optionally, the temperatures of the first reduction and the second reduction are independently selected from 200 - 600°C, and the times of the first reduction and the second reduction are independently selected from 0.5 - 48 h.

[0029] Optionally, the temperatures of the first reduction and the second reduction are independently selected from any value of 200°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C or a range value between any two of the above.

[0030] Optionally, the times of the first reduction and the second reduction are independently selected from any value of 0.5 h, 2 h, 4 h, 8 h, 12 h, 16 h, 20 h, 24 h, 36 h, 48 h or a range value between any two of the above.

[0031] Optionally, the atmospheres of the first reduction and the second reduction are independently selected from at least one of hydrogen, methane, ethane, and carbon monoxide.

[0032] Optionally, the pH value of the mixture II is 6 - 9.

[0033] Optionally, the pH value of the mixture II is independently selected from any value of 6, 7, 8, 9 or a range value between any two of the above.

[0034] Optionally, the temperature of the aging is 20 - 75°C, and the time of the aging is 2 - 48 h.

[0035] Optionally, the temperature of the aging is independently selected from any value of 20°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 75°C or a range value between any two of the above.

[0036] Optionally, the time of the aging is independently selected from any value of 2 h, 4 h, 8 h, 12 h, 16 h, 20 h, 24 h, 36 h, 48 h or a range value between any two of the above.

[0037] According to another aspect of the present application, there is provided a method for catalytic dehydrogenation amination of fatty alcohols to prepare fatty nitriles using the above-mentioned copper - lanthanum - based catalyst, and the method includes:

[0038] In an ammonia atmosphere, the fatty alcohol is contacted with a copper-lanthanum-based catalyst for reaction to obtain the fatty nitrile.

[0039] Optionally, the fatty alcohol is selected from at least one of ethanol, n-propanol, n-butanol, n-pentanol, n-hexanol, n-heptanol, n-octanol, lauryl alcohol, and myristyl alcohol.

[0040] Optionally, the molar ratio of ammonia to the fatty alcohol is 1 to 50:1.

[0041] Optionally, the molar ratio of ammonia to the fatty alcohol is 5 to 20:1.

[0042] Optionally, the reaction pressure is 0.1 to 0.5 MPa.

[0043] Optionally, the reaction pressure is independently selected from any value of 0.1 MPa, 0.2 MPa, 0.3 MPa, 0.4 MPa, 0.5 MPa or the range value between any two of the above.

[0044] Optionally, the reaction pressure is 0.1 to 0.2 MPa.

[0045] Optionally, the reaction temperature is 220 to 400 °C.

[0046] Optionally, the reaction temperature is independently selected from any value of 220 °C, 250 °C, 260 °C, 280 °C, 300 °C, 320 °C, 350 °C, 360 °C, 380 °C, 400 °C or the range value between any two of the above.

[0047] Optionally, the reaction temperature is 250 to 350 °C.

[0048] Optionally, the mass hourly space velocity of the fatty alcohol is 0.1 to 10 h -1 。

[0049] Optionally, the mass hourly space velocity of the fatty alcohol is independently selected from 0.1 h -1 、1 h -1 、2 h -1 、3 h -1 、4 h -1 、5 h -1 、6 h -1 、7 h -1 、8 h -1 、9 h -1 、10 h -1 or the range value between any two of them.

[0050] Optionally, the mass hourly space velocity of the fatty alcohol is 0.1 to 4 h -1 。

[0051] As an optional implementation, the present application is achieved through the following technical solutions:

[0052] A preparation method of a copper-lanthanum-based catalyst, the copper-lanthanum-based catalyst comprising a silicon-based carrier and metal active components copper and lanthanum, and the component contents thereof are: copper 1 wt% to 40 wt%, lanthanum 0.1 wt% to 10 wt%, and the rest is the silicon-based carrier; wherein copper and lanthanum are introduced into the carrier simultaneously by an impregnation method or a co-precipitation method to obtain a silicon-based catalyst precursor loaded with copper-lanthanum, and then the catalyst precursor is calcined and reduced and activated to obtain the copper-lanthanum-based catalyst.

[0053] Optionally, the steps for preparing the silicon-based catalyst precursor of copper-lanthanum by the impregnation method are as follows:

[0054] (1) Dissolve copper salt and lanthanum salt in water and stir to obtain a copper-lanthanum salt solution;

[0055] (2) Impregnate the copper-lanthanum salt solution onto the silicon-based carrier by an equal-volume impregnation method or a stepwise impregnation method, and after sufficient mixing, let it stand at room temperature for 2 to 24 h;

[0056] (3) Dry the mixture at 80 to 150 °C for 1 to 48 h to obtain the silicon-based catalyst precursor loaded with copper-lanthanum.

[0057] Optionally, the steps for preparing the silicon-based catalyst precursor of copper-lanthanum by the co-precipitation method are as follows:

[0058] (1) Dissolve copper salt and lanthanum salt in water and stir to obtain solution a;

[0059] (2) Dissolve the precipitant in water and stir to obtain solution b;

[0060] (3) Disperse the silicon-based carrier in water and stir, and add solution a and solution b in parallel, control the pH = 6 to 9, and age at 20 to 75 °C for 2 to 48 h;

[0061] (4) Filter and wash the mixture, and dry it at 80 to 150 °C for 1 to 48 h to obtain the silicon-based catalyst precursor loaded with copper-lanthanum;

[0062] Calcine the catalyst precursor at 300 to 700 °C for 2 to 48 h, and treat it with a reducing gas at 200 to 600 °C for 0.5 to 48 h to obtain the copper-lanthanum-based catalyst.

[0063] In the present application, the copper-lanthanum-based catalyst is used for catalyzing the reaction of dehydrogenation and amination of fatty alcohols to prepare fatty nitriles.

[0064] Optionally, a fixed bed is used as the reactor for the reaction.

[0065] Optionally, the reaction steps are as follows:

[0066] Fill the copper-lanthanum-based catalyst in the middle of a fixed bed, heat it to a specified temperature, introduce ammonia gas, and pump in fatty alcohol for reaction.

[0067] Optionally, the copper-lanthanum-based catalyst is pelletized, with a pressure of 1-10 MPa and a particle size of 20-80 mesh.

[0068] The beneficial effects that this application can produce include:

[0069] 1) The preparation method of the copper-lanthanum-based catalyst provided by this application, and the copper-lanthanum-based catalyst prepared by it is used in the reaction of dehydrogenative amination of fatty alcohol to fatty nitrile. The catalyst prepared by this method can significantly improve the production efficiency of fatty nitrile, and the stability and service life of the catalyst are significantly improved. Among them, the conversion rate of the fatty alcohol exceeds 80%. The selectivity of fatty nitrile exceeds 80%; The catalyst operates stably for more than 150 h, and the change in bed pressure is less than 0.1 MPa.

[0070] 2) Using fatty alcohol as a reactant to prepare fatty nitrile provided by this application, the yield of fatty alcohol is large, the synthesis route is mature, and the added value of the fatty nitrile generated by the dehydrogenative amination reaction of fatty alcohol is high, and it has a wide range of applications in multiple fields.

[0071] 3) The copper-lanthanum-based catalyst provided by this application has the following two advantages: the sources of the carrier and the metal precursor are wide and the price is low; Compared with a single copper component, the introduction of lanthanum strengthens the dispersion of copper species and the exposure of high-active sites, can effectively reduce the reaction activation energy, and produces fatty nitrile with high selectivity at a lower reaction temperature, and the catalyst shows a lower carbon deposition rate.

[0072] 4) The copper-lanthanum-based catalyst provided by this application is easy to prepare and easy to scale up. When used in the dehydrogenative amination reaction of fatty alcohol, the substrate has wide adaptability, no solvent is required, and the product is easy to separate and purify, and it has a good application prospect in the field of converting fatty alcohol into high-value chemicals. Description of the Drawings

[0073] Figure 1 It is the transmission electron microscope photograph of the sample obtained in Example 1 of this application (the scale bar in the figure is 100 nm).

[0074] Figure 2 It is the thermogravimetric curve of the sample obtained in Example 1 of this application after reaction. Detailed Description of the Invention

[0075] The following describes this application in detail with reference to the examples, but this application is not limited to these examples.

[0076] Unless otherwise specified, the raw materials in the examples of this application are all purchased through commercial channels.

[0077] Gas chromatography analysis (Varian 3800, FID detector, capillary column PoraPLOTQ-HT).

[0078] TEM images were recorded using a JEM-2100 electron microscope.

[0079] Thermogravimetric and differential thermal analysis (TG-DTG) were carried out on a TA SDTQ600 analyzer.

[0080] The reaction products were analyzed by Agilent 7890B chromatography.

[0081] Example 1

[0082] Preparation of copper-lanthanum-based catalyst: Preparation of 15Cu / 3La-meso SiO 2 -IM catalyst. The process of preparing the catalyst is as follows:

[0083] Weigh 5.10 g of copper nitrate and 0.81 g of lanthanum nitrate, add them to a beaker containing 25 mL of distilled water, stir until completely dissolved, and then impregnate 10.6 g of mesoporous silica support with equal volume. Let it stand at room temperature for 24 h, dry at 80 °C for 8 h, then calcine at 400 °C for 2 h, and reduce at 350 °C for 4 h in a hydrogen atmosphere to obtain 15Cu / 3La-meso SiO 2 -IM catalyst. It can be Figure 1 seen that the metal particle size of the catalyst is less than 5 nm.

[0084] Example 2

[0085] Preparation of copper-lanthanum-based catalyst: Preparation of 15Cu / 3La-meso SiO 2 -CP catalyst

[0086] Weigh 5.10 g of copper nitrate and 0.81 g of lanthanum nitrate, add them to a beaker containing 125 mL of distilled water, stir until completely dissolved, and prepare solution a. Weigh 10.6 g of sodium carbonate, add it to a beaker containing 110 mL of distilled water, stir until completely dissolved, and prepare solution b. Weigh 10.6 g of mesoporous silica support, suspend it in a round-bottom flask containing 135 mL of distilled water, and place it in a constant-temperature water bath and heat up to 50 °C. Add solution a and solution b dropwise in parallel into the round-bottom flask, stir the solution to keep the pH = 9, and age for 12 h. After naturally cooling to room temperature, filter, wash the filter cake three times with deionized water, then take out the filter cake and put it into an oven, dry at 90 °C for 8 h, then calcine at 400 °C for 4 h, and reduce at 300 °C for 3 h in a hydrogen atmosphere to obtain 15Cu / 3La-mesoSiO 2 -CP catalyst; The Cu content of the catalyst is 15 wt.%, and the La content is 3 wt.%.

[0087] Examples 3 - 10

[0088] Example 3 is different from Example 1 only in that the catalyst support is silica white, and the catalyst number is 15Cu / 3La-WH-IM.

[0089] Example 4 is different from Example 1 only in that the copper content of the catalyst is 20 wt%, and the catalyst number is 20Cu / 3La-meso SiO 2 -IM.

[0090] Example 5 is different from Example 2 only in that the precipitant is 20.3 g of urea, and the catalyst number is 15Cu / 3La-meso SiO 2 -UR-CP.

[0091] Example 6 is different from Example 1 only in that the copper content of the catalyst is 10 wt% and the lanthanum content is 9 wt%, and the catalyst number is 10Cu / 9La-meso SiO 2 -IM.

[0092] Example 7 is different from Example 1 only in that the copper content of the catalyst is 24 wt%, the catalyst support is macroporous silica gel, and the catalyst number is 24Cu / 3La-marco SiO 2 -IM.

[0093] Example 8 is different from Example 2 only in that the copper salt is copper sulfate, the lanthanum salt is lanthanum sulfate, the copper content of the catalyst is 22 wt%, the lanthanum content is 6 wt%, and the catalyst number is 22Cu / 6La-meso SiO 2 -CP.

[0094] Example 9 is different from Example 2 only in that the catalyst support is macroporous silica gel, the precipitant is 15.2 g of ammonium carbonate, and the catalyst number is 15Cu / 3La-macro SiO 2 -AC-CP.

[0095] Example 10 is different from Example 1 only in that the copper-lanthanum based catalyst support is metakaolin, the copper content of the catalyst is 16 wt%, and the catalyst number is 16Cu / 3La-MK-IM.

[0096] Comparative Example 1

[0097] It is different from Example 1 only in that no lanthanum salt is used during the synthesis process, and the copper content is controlled to be 15 wt.%, and the obtained catalyst is 15Cu-meso SiO 2 -IM.

[0098] Comparative Example 2

[0099] The difference from Example 1 is only that no copper salt is used during the synthesis process, and the lanthanum content is controlled to be 3 wt.%, and the obtained catalyst is 3La-meso SiO 2 -IM.

[0100] Example 11

[0101] The catalysts prepared in Examples 1 to 10 and Comparative Examples 1 and 2 were used in the dehydrogenative amination reaction of butanol. The catalytic experiment was carried out in a fixed-bed reactor, and the specific conditions were as follows: the amount of catalyst used was 4 g, the granulation pressure was 9 MPa, the particle size was 20 - 40 mesh, and the tableted and granulated catalyst was added to the fixed-bed reactor and heated to 300 °C. Ammonia was introduced, and at the same time, butanol was pumped in. The mass space velocity of butanol was 1.5 h -1 , the molar ratio of ammonia to ethanol was 8:1, the reaction pressure was 0.1 MPa, and the products were analyzed by on-line gas chromatography (Varian 3800, FID detector, capillary column PoraPLOTQ-HT). The reaction results of the dehydrogenative amination of butanol over different catalysts are shown in Table 1:

[0102] Table 1 Reaction results of the dehydrogenative amination of butanol over different catalysts

[0103]

[0104]

[0105] Table 1 compares the activity and product changes in the reaction of dehydrogenative amination of butanol to butyronitrile over different catalysts. It can be seen from the reaction data that the copper-lanthanum-based catalyst support, metal content, metal precursor type, and loading method have a certain influence on the reaction results. The catalysts in Examples 1 - 10 all achieved a butanol conversion rate of over 80% and a butyronitrile selectivity of over 80% within 200 h. Compared with the catalysts loaded with copper and lanthanum separately, the use of a copper-lanthanum bimetallic component catalyst has good reaction activity, high butyronitrile selectivity, and good catalytic life. After the catalyst in Example 1 was reacted for 200 h, the thermogravimetric curve was as Figure 2 shown, and the carbon deposition amount was less than 1.5 wt%, indicating that the catalyst has good anti-carbon deposition ability.

[0106] Example 12

[0107] The catalysts prepared in Example 1 and Example 2 were used in the dehydrogenative amination reactions of different fatty alcohols. The catalytic experiment was carried out in a fixed-bed reactor, and the specific conditions were as follows: the amount of catalyst used was 4 g, the granulation pressure was 9 MPa, the particle size was 20 - 40 mesh, and the tableted and granulated catalyst was added to the fixed-bed reactor and heated to 330 °C. Ammonia was introduced, and at the same time, fatty alcohol was pumped in. The mass space velocity of fatty alcohol was 1.1 h -1, the molar ratio of ammonia to ethanol was 8:1, the reaction pressure was 0.1 MPa, and the products were analyzed by on-line gas chromatography (Varian 3800, FID detector, capillary column PoraPLOTQ-HT). The reaction results of catalytic dehydrogenative amination of fatty alcohols over different catalysts are shown in Table 2:

[0108] Table 2 Reaction results of catalytic dehydrogenative amination of different fatty alcohols by catalysts

[0109]

[0110]

[0111] Table 2 compares the activities of different fatty alcohols in the dehydrogenative amination to fatty nitriles and the changes in products. From the reaction data, it can be seen that different fatty alcohol substrates have a certain influence on the reaction results, and the catalysts have good substrate universality. The catalysts in Example 1 and Example 2 both achieved a fatty alcohol conversion rate of over 80% and a fatty nitrile selectivity of over 80% within 200 h.

[0112] As described above, these are only several embodiments of the present application and do not impose any form of limitation on the present application. Although the present application is disclosed with preferred embodiments as above, it is not intended to limit the present application. Any person skilled in the art, without departing from the scope of the technical solution of the present application, making some changes or modifications using the technical content disclosed above is equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

Claims

1. A copper-lanthanum-based catalyst, characterized in that, the copper-lanthanum-based catalyst comprises a silicon-based support and active components supported on the silicon-based support; the active components include copper and lanthanum; the particle size of the copper-lanthanum-based catalyst is 2-15 nm.

2. The copper-lanthanum-based catalyst according to claim 1, characterized in that, in the copper-lanthanum-based catalyst, the loading amount of copper is 1 wt% - 40 wt%; preferably, in the copper-lanthanum-based catalyst, the loading amount of lanthanum is 0.1 wt% - 10 wt%.

3. A method for preparing the copper-lanthanum-based catalyst according to any one of claims 1 to 2, characterized in that, the preparation method comprises: immersing the silicon-based support in a mixture containing copper salt and lanthanum salt, standing, drying I, calcining I, reducing I, to obtain the copper-lanthanum-based catalyst; alternatively, by the co-precipitation method, a mixture II containing copper salt, lanthanum salt, precipitating agent, and silicon-based support is aged, dried II, calcined II, reduced II, to obtain the copper-lanthanum-based catalyst.

4. The preparation method according to claim 3, characterized in that, the copper salt is selected from at least one of copper nitrate, copper chloride, copper acetate, copper sulfate, basic copper sulfate; preferably, the lanthanum salt is selected from at least one of lanthanum nitrate, lanthanum chloride, lanthanum sulfate; preferably, the silicon-based support is selected from at least one of mesoporous silica, silica sol, white carbon black, activated silica, metakaolin, macroporous silica gel; preferably, the precipitating agent is selected from at least one of ammonia water, sodium carbonate, sodium bicarbonate, urea, ammonium carbonate.

5. The preparation method according to claim 3, characterized in that, the standing time is 2-24 h; preferably, the temperatures of drying I and drying II are independently selected from 80-150 °C, and the drying times of drying I and drying II are independently selected from 1-48 h; preferably, the temperatures of calcining I and calcining II are independently selected from 300-700 °C, and the calcining times of calcining I and calcining II are independently selected from 2-48 h; preferably, the temperatures of reducing I and reducing II are independently selected from 200-600 °C, and the reducing times of reducing I and reducing II are independently selected from 0.5-48 h.

6. The preparation method according to claim 3, characterized in that, the atmospheres of reducing I and reducing II are independently selected from at least one of hydrogen, methane, ethane, carbon monoxide; preferably, the pH value of the mixture II is 6-9; preferably, the aging temperature is 20-75 °C, and the aging time is 2-48 h.

7. A method for catalytically dehydrogenating and aminating fatty alcohols to prepare fatty nitriles using the copper-lanthanum-based catalyst according to any one of claims 1 to 2, characterized in that, the method comprises: under an ammonia atmosphere, contacting the fatty alcohol with the copper-lanthanum-based catalyst for reaction to obtain the fatty nitrile.

8. The method according to claim 7, characterized in that, the fatty alcohol is selected from at least one of ethanol, n-propanol, n-butanol, n-pentanol, n-hexanol, n-heptanol, n-octanol, lauryl alcohol, myristyl alcohol; preferably, the molar ratio of ammonia to the fatty alcohol is 1-50:1; Preferably, the molar ratio of the ammonia gas to the fatty alcohol is 5 to 20:

1.

9. According to the method described in claim 7, wherein, the reaction pressure is 0.1 to 0.5 MPa; Preferably, the reaction pressure is 0.1 to 0.2 MPa; Preferably, the reaction temperature is 220 to 400 °C; Preferably, the reaction temperature is 250 to 350 °C.

10. According to the method described in claim 7, wherein, The mass hourly space velocity of the fatty alcohol is 0.1 to 10 h -1 ; Preferably, the mass hourly space velocity of the fatty alcohol is 0.1 to 4 h -1 .

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