Method for preparing octanal

Abstract

The invention relates to the technical field of octanal preparation, and discloses a method for preparing octanal, which comprises the following steps: in the presence of a solvent and a catalyst, octenal is contacted with hydrogen; the catalyst comprises a carrier and an active component loaded on the carrier, the carrier is aluminum oxide microspheres modified by a nitrogen-containing high-molecular polymer, the active component is at least one of Ni and Co, and the content of the active component in the catalyst is 5-30wt% in terms of metal elements. According to the present invention, with the catalyst and the method, the octenal can be selectively hydrogenated into the octanal under the liquid phase reaction condition, and the conversion rate of the octenal and the selectivity of the octanal are high.

Description

Technical Field

[0001] This invention relates to the technical field of octaldehyde preparation, and more specifically, to a method for preparing octaldehyde. Background Technology

[0002] Octaldehyde is an important chemical product that can be used as an organic raw material. It has potential antibacterial properties and, due to its diverse aroma profile, can be used as a flavoring agent, possessing a pleasant fragrance with a long-lasting scent, enhancing the naturalness of flavorings. Octaldehyde is also used as a citrus flavoring in beverages and ice cream, demonstrating its wide range of applications. However, octanaldehyde is highly susceptible to oxidation, forming octanoic acid, which leads to complete spoilage.

[0003] The industrial production of octaldehyde is mainly obtained through the hydrogenation reaction of octenal. Octenal is an α,β-unsaturated aldehyde containing both C=C and C=O bonds. Thermodynamically, the bond energy of the C=C bond is 615 kJ / mol, and the bond energy of the C=O bond is 715 kJ / mol, with both bonds exhibiting conjugation. Kinetically, it is difficult to hydrogenate only the C=C bonds without proceeding to the C=O bonds. Therefore, octaldehyde, as an intermediate product of the octenal hydrogenation reaction, requires a catalyst with extremely high selectivity.

[0004] Currently, research mainly focuses on the hydrogenation of octenal to octanol, with relatively little research on the selective preparation of octanal. CN107930647A discloses a catalyst for the preparation of octanal, which uses a noble metal active component Pd and at least one of Ag, Co, and Rh supported on Al2O3. However, using a noble metal component significantly increases the overall cost of the catalyst. Furthermore, this invention involves a gas-phase reaction, requiring octenal to be heated to 180-220℃ to completely vaporize before hydrogen is introduced, resulting in high energy consumption.

[0005] In conclusion, it is essential to develop a hydrogenation catalyst for octenal with high conversion rate and good selectivity. Summary of the Invention

[0006] The purpose of this invention is to overcome the aforementioned problems in the prior art and to provide a method for preparing octanal.

[0007] To achieve the above objectives, the present invention provides a method for preparing octaldehyde, the method comprising: contacting octenal with hydrogen in the presence of a solvent and a catalyst; the catalyst comprising a support and an active component supported on the support, the support being alumina microspheres modified with a nitrogen-containing polymer, the active component being at least one of Ni and Co, and the content of the active component in the catalyst, calculated as a metal element, being 5-30 wt%.

[0008] This invention utilizes a specific alumina microsphere support modified with a nitrogen-containing polymer and an active component loaded on the support to prepare a catalyst with selective hydrogenation properties. Using the catalyst and method of this invention, the selective hydrogenation of octenal to octanal can be achieved under liquid-phase reaction conditions, with high conversion rates of octenal and high selectivity for octanal. Detailed Implementation

[0009] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0010] In this invention, unless otherwise specified, the diameter of the alumina microspheres refers to the average diameter of the alumina microspheres.

[0011] This invention provides a method for preparing octaldehyde, the method comprising: contacting octenal with hydrogen in the presence of a solvent and a catalyst; the catalyst comprising a support and an active component supported on the support, the support being alumina microspheres modified with a nitrogen-containing polymer, the active component being at least one of Ni and Co, and the content of the active component in the catalyst, calculated as a metal element, being 5-30 wt%.

[0012] According to the present invention, preferably, the active component is Ni. When the active component of the catalyst in the present invention is Ni, better conversion rate and selectivity of octenal can be obtained.

[0013] According to the present invention, preferably, the weight ratio of octenal to solvent is 1:3-25, and can be 1:3, 1:5, 1:9, 1:10, 1:12, 1:15, 1:18, 1:20, 1:23, 1:25, or any two of the above values ​​within a range. Using the amounts of octenal and solvent described in this invention is beneficial for improving the selectivity and yield of octenal.

[0014] According to the present invention, more preferably, the weight ratio of octenal to solvent is 1:4-15.

[0015] The inventors of this invention have discovered that the catalyst used in this invention is suitable for preparing isooctaldehyde from isooctaldehyde, and particularly suitable for preparing 2-ethyl-1-hexanal with high selectivity from 2-ethyl-2-hexenal. Therefore, preferably, the isooctaldehyde is 2-ethyl-2-hexenal and the isooctaldehyde is 2-ethyl-1-hexanal.

[0016] In this invention, the solvent is a C4-C8 saturated alcohol, preferably octanol, more preferably isooctol, and even more preferably 2-ethyl-1-hexanol.

[0017] According to the present invention, preferably, the contact conditions include: a reaction temperature of 60-110°C, a hydrogen pressure of 2-4 MPa, and a volume hourly space velocity of 1-5 h⁻¹. -1 The contact conditions provided by this invention can further improve the conversion rate of octenal.

[0018] In this invention, the selective hydrogenation reaction of octenal to prepare octaldehyde can be carried out in either a batch reaction device, such as an autoclave, or in a continuous feed device, such as a continuous feed fixed bed. Preferably, the reaction is carried out in a continuous feed fixed bed, which can further reduce the operation process, reduce labor costs, and overcome the problem that traditional batch reaction devices are not conducive to continuous production.

[0019] According to the present invention, preferably, the method further includes preparing the catalyst by the following steps: placing alumina microspheres in a nitrogen-containing polymer solution, obtaining alumina microspheres modified with nitrogen-containing polymer by a solvothermal method, and then loading the active component onto the alumina microspheres modified with nitrogen-containing polymer.

[0020] According to the present invention, preferably, the diameter of the alumina microspheres is 200-800 μm and the coefficient of variation is 3-8%.

[0021] According to the present invention, the source of the alumina microspheres is not particularly limited, as long as they meet the ranges defined by the particle diameter and coefficient of variation of the alumina microspheres. The alumina microspheres can be prepared in-house or by referring to methods in the literature. Preferably, the preparation method of the alumina microspheres includes: using aluminum sol as the dispersed phase and an organic solvent as the continuous phase, forming droplets under the shearing action of the continuous phase, solidifying to obtain gel microspheres, and then drying and calcining to obtain alumina microspheres.

[0022] In the method for preparing alumina microspheres according to the present invention, preferably, the solid content of the aluminum sol is 5-10 wt%.

[0023] In the method for preparing alumina microspheres according to the present invention, preferably, the organic solvent is a C1-C10 monohydric saturated alcohol, preferably octanol.

[0024] In the method for preparing alumina microspheres according to the present invention, preferably, the drying conditions include: a drying temperature of 80-140°C and a drying time of 1-10 h.

[0025] In the method for preparing alumina microspheres according to the present invention, preferably, the calcination conditions include: a calcination temperature of 500-800℃ and a calcination time of 3-6h.

[0026] In this invention, the alumina microspheres are prepared in a microchannel reactor. This invention does not particularly limit the type of microchannel reactor. The microchannel reactor can be a single-channel reactor or a multi-channel reactor. Preferably, the microchannel reactor is a multi-channel reactor.

[0027] According to a further preferred embodiment of the present invention, the multi-channel reactor is an eight-channel reactor. The preferred structure of the eight-channel reactor in the present invention is that of the eight-channel reactor disclosed in CN113041974A, which is used in the apparatus for large-scale preparation of alumina microspheres. The structure of the eight-channel reactor is described below. The eight-channel reactor includes a continuous phase distribution layer, a first droplet generation layer, a second droplet generation layer, and a dispersed phase distribution layer. The continuous phase distribution layer consists of petal-shaped resistance distribution channels with eight fluid outlets at their ends, a continuous phase vertical inlet, and four positioning holes. Each branch of the fluid path is called a stage, and a certain resistance is applied before each fluid branch. The width of the channel decreases as the circumference radius of the starting end of each stage increases. The first droplet generation layer has eight T-shaped channels, four positioning holes, and eight through holes to meet the requirements of the continuous phase flowing from the distribution layer to the generation layer. The second droplet generation layer has a similar structure to the first droplet generation layer, and also has eight droplet outlets at the end of the main T-shaped channel. The dispersed phase distribution layer has a similar structure to the continuous phase distribution layer, and in addition to the petal-shaped resistance distribution channels and the eight dispersed phase outlets at their ends, it also has a dispersed phase fluid inlet and eight product outlets.

[0028] According to the present invention, preferably, the process of preparing alumina microspheres is described using an eight-channel reactor as an example. Using aluminum sol as the dispersed phase and an organic solvent as the continuous phase, the flow rate of the continuous phase is adjusted to fill the continuous phase distribution layer and flow into the droplet generation layer, then out through the outlet. The flow rate of the continuous phase is eventually stabilized at 6-10 mL / min, preferably 7-9 mL / min. The flow rate of the dispersed phase is then adjusted to 1-4 mL / min, preferably 2-3 mL / min, to fill the dispersed phase distribution layer and flow into the droplet generation layer. Further, droplets are generated under the shearing action of the continuous phase. The droplets solidify in an oil column to obtain gel microspheres. After drying and calcination, alumina microspheres with a diameter of 200-800 μm and a coefficient of variation of 3-8% are obtained.

[0029] In the method for preparing the catalyst according to the present invention, the mass ratio of the alumina microspheres to the nitrogen-containing polymer solution is 1:1-10, which can be 1:1, 1:2, 1:3, 1:5, 1:7, 1:9, 1:10, or any two of the above values ​​within a range. Preferably, the mass ratio of the alumina microspheres to the nitrogen-containing polymer solution is 1:3-7.

[0030] In the method for preparing the catalyst according to the present invention, the conditions of the solvothermal method include: a temperature of 100-120°C and a time of 4-10 h.

[0031] In the method for preparing the catalyst according to the present invention, the nitrogen-containing polymer is selected from one or more of polyvinylimidazole, polyvinylpyrrolidone and polyvinylpyridine, preferably polyvinylimidazole.

[0032] In the method for preparing the catalyst according to the present invention, there is no particular limitation on the concentration of the nitrogen-containing polymer solution. However, in order to further improve the selectivity of octanal, preferably, the concentration of the nitrogen-containing polymer solution is 0.2-1.5 wt%, which can be 0.2 wt%, 0.5 wt%, 0.8 wt%, 1.2 wt%, 1.5 wt%, or any two of the above values ​​within the range.

[0033] In the method for preparing the catalyst according to the present invention, the solvent in the nitrogen-containing polymer solution is selected from one or a combination of methanol and ethanol.

[0034] In the method for preparing the catalyst according to the present invention, the active component is loaded onto alumina microspheres modified with nitrogen-containing polymer by immersing the alumina microspheres modified with nitrogen-containing polymer in an active component precursor solution, followed by drying and calcination to obtain the catalyst.

[0035] In the method for preparing the catalyst according to the present invention, the concentration of the active component precursor solution, calculated by metal element, is 20-80 wt%, and can be 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, or any two of the above values ​​within a range.

[0036] In the method for preparing the catalyst according to the present invention, the active component precursor is at least one selected from nickel nitrate, nickel carbonate, and cobalt nitrate.

[0037] In the method for preparing the catalyst according to the present invention, preferably, the impregnation conditions include: a temperature of 40-80°C and a time of 0.1-1 h.

[0038] In the method for preparing the catalyst according to the present invention, preferably, the drying conditions include: a drying temperature of 90-140°C and a drying time of 2-6 hours.

[0039] In the method for preparing the catalyst according to the present invention, preferably, the calcination temperature includes: a calcination temperature of 300-400℃ and a calcination time of 2-6h.

[0040] According to a preferred embodiment of the present invention, the catalyst needs to be reduced before use. The reduction atmosphere can be hydrogen, wherein the reduction temperature is 400-600°C and the reduction time is 3-6 hours.

[0041] The present invention will be described in detail below through embodiments.

[0042] Octenal conversion rate = (moles of octenal in the raw material - moles of unreacted octenal) ÷ ​​moles of octenal in the raw material × 100%.

[0043] Octal yield = number of moles of octal in the product ÷ (number of moles of octenal in the raw material - number of moles of unreacted octenal) × 100%.

[0044] The coefficient of variation is calculated using the following formula:

[0045]

[0046] CV: Coefficient of variation, n: Alumina microsphere count, X i Diameter of a single alumina microsphere. Average diameter of all alumina microspheres.

[0047] Preparation Example 1

[0048] Monodisperse alumina microspheres were prepared using a microchannel reactor. The dispersed phase was an aluminum sol (obtained by reacting aluminum hydroxide with excess sodium hydroxide) with a solid content of 7.5 wt%. The continuous phase and the liquid in the oil column were both organic solvents, specifically octanol. First, the flow rate of the continuous phase was adjusted to fill the continuous phase distribution layer and flow into the droplet formation layer, then flow out from the outlet. The continuous phase flow rate was eventually stabilized at 7 mL / min. Then, the dispersed phase flow rate was adjusted to 2 mL / min to fill the dispersed phase distribution layer and flow into the droplet formation layer, further generating droplets under the shearing action of the continuous phase. The droplets solidified in the oil column to obtain gel microspheres. After drying at 120℃ for 12 h and calcining at 600℃ for 4 h, alumina microspheres with an average diameter of 345 μm and a coefficient of variation of 6.5% were obtained.

[0049] Preparation Example 2

[0050] Monodisperse alumina microspheres were prepared using an eight-channel microreactor. The dispersed phase was an aluminum sol (obtained by reacting aluminum hydroxide with excess sodium hydroxide) with a solid content of 7.5 wt%. The continuous phase and the liquid in the oil column were both organic solvents, specifically octanol. First, the flow rate of the continuous phase was adjusted to fill the continuous phase distribution layer and flow into the droplet formation layer, then flow out from the outlet. The continuous phase flow rate was eventually stabilized at 9 mL / min. Then, the dispersed phase flow rate was adjusted to 3 mL / min to fill the dispersed phase distribution layer and flow into the droplet formation layer, further generating droplets under the shearing action of the continuous phase. The droplets solidified in the oil column to obtain gel microspheres. After drying at 120 °C for 12 h and calcining at 600 °C for 4 h, alumina microspheres with an average diameter of 480 μm and a coefficient of variation of 7.2% were obtained.

[0051] Example 1

[0052] 1) 200g of alumina microspheres obtained in Preparation Example 1 were immersed in a 0.2wt% ethanol solution of polyvinylimidazole, with a mass ratio of alumina microspheres to ethanol solution of polyvinylimidazole of 1:10. The mixture was then transferred to a hydrothermal reactor and reacted at 100°C for 10h. After cooling and filtration, the polymer alumina microsphere composite carrier was obtained.

[0053] 2) Take 80wt% nickel nitrate aqueous solution and put it in a beaker. Place 200g of alumina microspheres modified with nitrogen-containing polymer in the nickel nitrate aqueous solution. After soaking at 60℃ for 0.5h, dry at 120℃ for 4h and calcine at 300℃ for 6h under air conditions. The amount of nickel nitrate added makes the nickel content in the catalyst 20wt%. This catalyst is denoted as A1.

[0054] Example 2

[0055] 1) 200g of alumina microspheres obtained in Preparation Example 2 were immersed in a 0.1wt% ethanol solution of polyvinylimidazole, with a mass ratio of alumina microspheres to ethanol solution of polyvinylimidazole of 1:2; then the mixture was transferred to a hydrothermal reactor and reacted at 100°C for 10h, and cooled and filtered to obtain a polymer alumina microsphere composite carrier.

[0056] 2) Take 50wt% nickel nitrate aqueous solution and put it in a beaker. Place 200g of alumina microspheres modified with nitrogen-containing polymer in the nickel nitrate aqueous solution. After soaking at 40℃ for 1h, dry at 120℃ for 3h and calcine at 350℃ for 6h under air conditions. The amount of nickel nitrate added makes the nickel content in the catalyst 10wt%. The catalyst is denoted as A2.

[0057] Example 3

[0058] 1) 200g of alumina microspheres obtained in Preparation Example 1 were immersed in a 0.5wt% ethanol solution of polyvinylpyridine, with a mass ratio of alumina microspheres to ethanol solution of polyvinylpyridine of 1:3; then the mixture was transferred to a hydrothermal reactor and reacted at 100°C for 8h, and cooled and filtered to obtain a polymer alumina microsphere composite carrier.

[0059] 2) Take a 20wt% nickel nitrate aqueous solution and place it in a beaker. Place 200g of alumina microspheres modified with nitrogen-containing polymer in the nickel nitrate aqueous solution. After soaking at 40℃ for 0.2h, dry at 90℃ for 2h and calcine at 300℃ for 6h under air conditions. The amount of nickel nitrate added makes the nickel content in the catalyst 5.5wt%. This catalyst is denoted as A3.

[0060] Example 4

[0061] 1) 200g of alumina microspheres obtained in Preparation Example 1 were immersed in a 1wt% ethanol solution of polyvinylpyridine, with a mass ratio of alumina microspheres to ethanol solution of polyvinylpyridine of 1:5; then the mixture was transferred to a hydrothermal reactor and reacted at 100°C for 6h, and cooled and filtered to obtain a polymer alumina microsphere composite carrier.

[0062] 2) Take 40wt% nickel nitrate aqueous solution and put it in a beaker. Place 200g of alumina microspheres modified with nitrogen-containing polymer in the nickel nitrate aqueous solution. After soaking at 60℃ for 0.5h, dry at 120℃ for 4h and calcine at 400℃ for 3h under air conditions. The amount of nickel nitrate added makes the nickel content in the catalyst 10.7wt%. This catalyst is denoted as A4.

[0063] Example 5

[0064] 1) 200g of alumina microspheres obtained in Preparation Example 1 were immersed in a 1.5wt% ethanol solution of polyvinylpyridine, with a mass ratio of alumina microspheres to ethanol solution of polyvinylpyridine of 1:7; then the mixture was transferred to a hydrothermal reactor and reacted at 120°C for 10h, and cooled and filtered to obtain a polymer alumina microsphere composite carrier.

[0065] 2) Take 60wt% nickel nitrate aqueous solution and put it in a beaker. Place 200g of alumina microspheres modified with nitrogen-containing polymer in the nickel nitrate aqueous solution. After soaking at 80℃ for 0.1h, dry at 140℃ for 6h and calcine at 350℃ for 4h under air conditions. The amount of nickel nitrate added makes the nickel content in the catalyst 15.2wt%. This catalyst is denoted as A5.

[0066] Example 6

[0067] The catalyst was prepared according to the method of Example 1, except that nickel nitrate was replaced with cobalt nitrate, resulting in a catalyst with a cobalt loading of 20 wt%, denoted as A6.

[0068] Example 7

[0069] The catalyst was prepared according to the method of Example 1, except that step 1) further included: carbonizing alumina microspheres modified with nitrogen-containing polymer at 800°C for 8 hours under nitrogen protection, and finally obtaining a catalyst with a nickel content of 20 wt%, denoted as A7.

[0070] Comparative Example 1

[0071] 50g of a commercially available Al2O3 support was impregnated in a nickel nitrate solution and impregnated at 60°C for 0.5h. Then, it was dried at 120°C for 4h and calcined at 300°C for 6h to obtain a catalyst with a nickel content of 10wt%, denoted as B1.

[0072] Comparative Example 2

[0073] The catalyst was prepared according to the method of Example 1, except that the support used was alumina microspheres (without using polymers), and a catalyst with a nickel content of 20 wt% was finally obtained, denoted as B2.

[0074] Comparative Example 3

[0075] The catalyst was prepared according to the method of Example 1, except that the nitrogen-containing polymer was replaced with glucose, and finally a catalyst with a nickel content of 20 wt% was obtained, denoted as B3.

[0076] Comparative Example 4

[0077] The catalyst was prepared according to the method of Example 1, except that the content of the active component in the catalyst was 2 wt%, denoted as B4.

[0078] Comparative Example 5

[0079] The catalyst was prepared according to the method of Example 1, except that the active component in the catalyst was iron, and a catalyst with a loaded iron content of 20 wt% was finally obtained, which was denoted as B5.

[0080] Test Example 1

[0081] 25 mL of catalyst was loaded into a stainless steel fixed-bed reactor, and high-purity hydrogen was introduced at a flow rate of 300 mL / min. The reactor was heated to 400 °C to reduce the catalyst for 4 hours. Then, high-purity N2 was introduced at a flow rate of 300 mL / min. When the temperature dropped to the set value, octenal, octanol, and H2 were introduced. The amounts of octenal and octanol added, as well as the reaction temperature, pressure, and volume hourly space velocity (VHSV) (total VHSV of octenal and octanol), are shown in Table 1. After the system stabilized, the composition was analyzed by gas chromatography, and the results are shown in Table 1.

[0082] Table 1

[0083]

[0084]

[0085] As can be seen from the results in Table 1, the catalysts prepared using the examples of this invention and the reaction conditions exhibit significantly better octenal conversion and octaldehyde selectivity. In this invention, the catalyst prepared in Example 1, under the preferred reaction conditions, achieves better octenal conversion and octaldehyde selectivity. Under the same reaction conditions, compared to the catalysts prepared in Example 6, the catalyst with a reactivity of Ni achieves better octenal conversion and octaldehyde selectivity.

[0086] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing octaldehyde, characterized in that, The method includes: contacting octenal with hydrogen in the presence of a solvent and a catalyst; The catalyst comprises a support and an active component loaded on the support. The support is alumina microspheres modified with a nitrogen-containing polymer. The active component is at least one of Ni and Co. The content of the active component in the catalyst, calculated as a metal element, is 5-30 wt%.

2. The method according to claim 1, wherein the weight ratio of octenal to solvent is 1:3-25, more preferably 1:4-15.

3. The method according to claim 1, wherein, The octenal is isooctenal, preferably 2-ethyl-2-hexenal; And / or, the octanal is isooctaldehyde, preferably 2-ethyl-1-hexanal.

4. The method according to claim 1, wherein, The solvent is a C4-C8 saturated alcohol; Preferably, the solvent is octanol; More preferably, the octanol is 2-ethyl-1-hexanol.

5. The method according to claim 1, wherein, The contact conditions include: a reaction temperature of 60-110°C, a hydrogen pressure of 2-4 MPa, and a volume hourly space velocity (VHSV) of octenal and solvent of 1-5 h⁻¹. -1 ; And / or, the contact is carried out in a continuously fed apparatus, preferably a continuously fed fixed bed.

6. The method according to claim 1, wherein, The method further includes preparing the catalyst by the following steps: placing alumina microspheres in a nitrogen-containing polymer solution, obtaining alumina microspheres modified with nitrogen-containing polymer by a solvothermal method, and then loading the active component onto the alumina microspheres modified with nitrogen-containing polymer.

7. The method according to claim 6, wherein, The mass ratio of the alumina microspheres to the nitrogen-containing polymer solution is 1:1-10, preferably 1:3-7; And / or, the conditions for the solvothermal method include: a temperature of 100-120°C and a time of 4-10 h.

8. The method according to claim 6, wherein, The nitrogen-containing polymer is selected from one or more of polyvinylimidazolium, polyvinylpyrrolidone, and polyvinylpyridine. And / or, the concentration of the nitrogen-containing polymer solution is 0.2-1.5 wt%; And / or, the solvent in the nitrogen-containing polymer solution is selected from one or a combination of methanol or ethanol.

9. The method according to any one of claims 6-8, wherein, The active component is loaded onto alumina microspheres modified with nitrogen-containing polymers by immersing the alumina microspheres modified with nitrogen-containing polymers in a solution of the active component precursor, followed by drying and calcination to obtain the catalyst.

10. The method according to claim 9, wherein, The concentration of the active component precursor solution, calculated by metal element, is 20-80 wt%. And / or, the active component precursor is at least one of nickel nitrate, nickel carbonate, and cobalt nitrate; And / or, the impregnation conditions include: a temperature of 40-80°C and a time of 0.1-1 h; And / or, the drying conditions include: a drying temperature of 90-140℃ and a drying time of 2-6 hours; And / or, the calcination conditions include: a calcination temperature of 300-400℃ and a calcination time of 2-6h.

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