Hydrogenation catalyst and preparation method and application thereof

Abstract

The invention relates to a hydrogenation catalyst and a preparation method and application thereof, the preparation method of the hydrogenation catalyst comprises the following steps: (1) uniformly mixing a nickel salt, a co-catalytic metal salt and a solvent, mixing the obtained active component solution with gamma-Al2O3 for dipping, and drying to obtain a catalyst precursor; and (2) sequentially roasting and activating the catalyst precursor obtained in the step (1) to obtain the hydrogenation catalyst. The hydrogenation catalyst prepared by the invention shows high activity, high selectivity and stability in hydrogenation reaction, can greatly improve the selectivity of 1, 4-butanediamine, reduces the generation of a byproduct tetrahydropyrrole, avoids the use of an auxiliary agent alkali in the hydrogenation process, reduces the operation difficulty of the hydrogenation process, and is beneficial to industrial production.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, and in particular to a hydrogenation catalyst and a preparation method and application thereof. Background Art

[0002] 1,4-Butanediamine is a diamine compound with two amino groups. It can react with compounds such as acids and aldehydes. It is mostly used to synthesize a variety of chemical substances, such as nylon, coatings, etc. It can also be used as an intermediate in the pharmaceutical industry. It is also used in the production of certain types of surfactants.

[0003] At present, the main production method of 1,4-butanediamine is chemical synthesis, that is, acrylonitrile and hydrocyanic acid are used as raw materials to synthesize succinonitrile under the action of alkaline catalyst, and succinonitrile is hydrogenated to obtain 1,4-butanediamine. From the mechanism of hydrogenation reaction, it can be seen that the main by-product of the reaction process is tetrahydropyrrole formed by the ring formation after the intermediate is deaminated, and the key to improving the selectivity of 1,4-butanediamine is to inhibit or reduce the occurrence of side reactions.

[0004] CN106748806A discloses a method for preparing diamines by hydrogenation of aliphatic dinitrile, which uses aliphatic dinitrile and hydrogen raw materials, dialkoxymethane as solvent, modified supported Ni-Co-Pb catalyst, and fluidized bed reactor to prepare aliphatic diamines. Dialkoxymethane and dinitrile are respectively gasified by metering pump and preheater; hydrogen is compressed by compressor and preheated; the three materials are fully mixed by mixer and pumped into fluidized bed reactor pre-installed with modified supported Ni-Co-Pb catalyst; after the reaction is completed, the product diamine is obtained by gas-liquid separation and continuous crystallization purification. However, the conversion rate and product selectivity of dinitrile in this method still need to be further improved.

[0005] CN112341339A discloses a method and device for synthesizing 1,4-butanediamine, wherein 1,4-butanediol raw material is fed into a cyclization reactor, and dehydrogenation cyclization is carried out under the condition of copper-based catalyst and 200-250°C to obtain γ-butyrolactone; the γ-butyrolactone is distilled and fed into an ammoniation reactor, and reacts with liquid ammonia at a set temperature for a certain period of time, and then the reaction is completed under the condition of 250°C and 5-10MPa to obtain γ-butyrolactam; the γ-butyrolactam is fed into an ammonolysis reactor, and an ammonolysis ring-opening reaction is carried out with ammonia gas under the condition of nitrate molecular sieve catalyst and 420-500°C to obtain 4-aminobutyronitrile; the dehydrated 4-aminobutyronitrile is fed into a hydrogenation reactor, and hydrogenated under the condition of 80-100°C with a molecular sieve loaded with nickel and cobalt as catalyst to obtain 1,4-butanediamine. However, the process flow is relatively complicated and not suitable for large-scale industrial production.

[0006] CN113797929A discloses a solid catalyst for catalytic synthesis of diethylenediamine, a method and a system device for preparing diethylenediamine using the same, wherein the solid catalyst comprises a carrier, an active component and an auxiliary agent supported on the carrier, wherein the active component comprises Ni and / or Co, and the auxiliary agent comprises a metal element and its oxide, wherein the metal element is selected from one or a combination of at least two of Mg, Ca, Zr, Mo, Ti, Cr, Cu, Fe, Ru, Rh, Pd, La or Ce. The selectivity of diethylenediamine in the method is relatively low, and further improvement is needed.

[0007] Therefore, in view of the shortcomings of the prior art, it is necessary to provide a hydrogenation catalyst with high activity, high selectivity and stability. Summary of the invention

[0008] The object of the present invention is to provide a hydrogenation catalyst and a preparation method and application thereof. The hydrogenation catalyst has high activity, high selectivity and stability and is applied in the process of preparing 1,4-butanediamine by hydrogenation of succinonitrile to significantly improve the selectivity of 1,4-butanediamine.

[0009] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a method for preparing a hydrogenation catalyst, the preparation method comprising the following steps:

[0011] (1) uniformly mixing nickel salt, catalytic metal salt and solvent, and mixing the obtained active component solution with γ-Al 2 O 3 Mixing and impregnating, and drying to obtain a catalyst precursor;

[0012] (2) The catalyst precursor obtained in step (1) is calcined and activated in sequence to obtain the hydrogenation catalyst.

[0013] The preparation method of the hydrogenation catalyst provided by the present invention is based on γ-Al 2 O 3 As carrier, in γ-Al 2 O 3 The main active ingredient nickel oxide is loaded on the surface, and potassium oxide and / or lanthanum oxide are added. The prepared hydrogenation catalyst can be used for hydrogenating succinonitrile to prepare 1,4-butanediamine. The obtained hydrogenation catalyst is eggshell-type. Compared with uniform catalysts, the hydrogenation catalyst shows high activity, high selectivity and stability in the hydrogenation reaction. At the same time, potassium and / or lanthanum metal elements are added during the preparation process to make the catalyst have a higher specific surface area.

[0014] Preferably, the catalytic metal salt in step (1) comprises potassium salt and / or lanthanum salt.

[0015] Preferably, the potassium salt comprises potassium nitrate and / or potassium phosphate.

[0016] Preferably, the lanthanum salt comprises lanthanum nitrate and / or lanthanum chloride.

[0017] Preferably, the nickel salt in step (1) comprises nickel nitrate and / or nickel chloride.

[0018] Preferably, in the active component solution of step (1), the mass fraction of nickel salt is 0.1-10%, the mass fraction of potassium salt is ≤1%, and the mass fraction of lanthanum salt is ≤1%.

[0019] The mass fraction of the nickel salt in the active component solution is 0.1-10%, for example, 0.1%, 1%, 3.5%, 4%, 5% or 10%, but is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable, preferably 3.5-5%.

[0020] The mass fraction of potassium salt in the active component solution is ≤1%, for example, it can be 1%, 0.6%, 0.4%, 0.3%, 0.1% or 0.05%, but is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable, preferably 0.3-0.6%.

[0021] The mass fraction of the lanthanum salt in the active component solution is ≤1%, for example, it can be 1%, 0.6%, 0.4%, 0.3%, 0.1% or 0.05%, but is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable, preferably 0.3-0.6%.

[0022] In the present invention, as the mass fraction of nickel doped in the hydrogenation catalyst increases and the mass fractions of potassium and lanthanum elements decrease, the selectivity of 1,4-butanediamine will gradually increase and then remain stable. Therefore, it is necessary to control the nickel salt, potassium salt and lanthanum salt in the active component solution within a reasonable range to ensure the selectivity of 1,4-butanediamine. If the content exceeds the limited range, the selectivity of 1,4-butanediamine will be adversely affected.

[0023] Preferably, the solvent in step (1) comprises any one of acetone, methyl ethyl ketone or ethanol, or a combination of at least two thereof. Typical but non-limiting combinations include a combination of acetone and methyl ethyl ketone, or a combination of acetone and ethanol, preferably acetone.

[0024] Preferably, the active component solution in step (1) is mixed with γ-Al 2 O 3 The mass ratio is (1-3):(0.3-1), for example, it can be 3:0.3, 1:0.3, 3:1 or 1:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0025] Preferably, the γ-Al in step (1) 2 O 3 The particle size is 2-4 mm, for example, 2 mm, 2.5 mm, 3 mm, 3.5 mm or 4 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0026] Preferably, the immersion temperature in step (1) is 20-50°C, for example, 20°C, 25°C, 30°C, 40°C or 50°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0027] Preferably, the immersion time in step (1) is 20-30 hours, for example, 20 hours, 22 hours, 25 hours, 28 hours or 30 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0028] Preferably, the drying temperature in step (1) is 80-140°C, for example, 80°C, 90°C, 100°C, 120°C or 140°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0029] Preferably, the drying time in step (1) is 10-20 hours, for example, 10 hours, 12 hours, 15 hours, 18 hours or 20 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0030] Preferably, the calcination temperature in step (2) is 300-500°C, for example, 300°C, 350°C, 400°C, 450°C or 500°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0031] Preferably, the calcination time in step (2) is 2-8 h, for example, 2 h, 3 h, 5 h, 6 h or 8 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0032] Preferably, the calcination in step (2) is carried out in a protective atmosphere.

[0033] Preferably, the protective atmosphere includes any one of nitrogen, argon or helium.

[0034] Preferably, the activation temperature in step (2) is 300-600°C, for example, 300°C, 350°C, 400°C, 500°C or 600°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0035] Preferably, the activation time in step (2) is 2-8 h, for example, 2 h, 3 h, 5 h, 6 h or 8 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0036] Preferably, the activation in step (2) is carried out in a hydrogen atmosphere.

[0037] In a second aspect, the present invention provides a hydrogenation catalyst, wherein the hydrogenation catalyst is prepared by the preparation method of the hydrogenation catalyst according to the first aspect, and the hydrogenation catalyst comprises γ-Al 2 O 3 And loaded on γ-Al 2 O 3 Nickel oxide and catalytic metal oxide on it.

[0038] The hydrogenation catalyst provided by the present invention has high activity, high selectivity and stability, and can significantly improve the selectivity of 1,4-butanediamine in the process of preparing 1,4-butanediamine by hydrogenating succinonitrile.

[0039] Preferably, the catalytically-promoting metal oxide comprises potassium oxide and / or lanthanum oxide.

[0040] In a third aspect, the present invention provides a use of the hydrogenation catalyst as described in the second aspect, wherein the hydrogenation catalyst is used to prepare 1,4-butanediamine, and the method for preparing 1,4-butanediamine comprises the following steps:

[0041] Succinonitrile is dissolved in a solvent, mixed with a hydrogenation catalyst, and then hydrogen is introduced to react to obtain 1,4-butanediamine.

[0042] The hydrogenation catalyst provided by the present invention is applied to the process of preparing 1,4-butanediamine by hydrogenating succinonitrile, which can greatly improve the selectivity of 1,4-butanediamine and reduce the generation of by-product tetrahydropyrrole. At the same time, the use of auxiliary alkali is avoided in the hydrogenation process, and the subsequent alkali removal operation of the hydrogenation process is omitted, which greatly reduces the operating difficulty of the hydrogenation process and is convenient for industrial production.

[0043] Preferably, the mass ratio of the solvent to succinonitrile is (0.1-20):1, for example, 0.1:1, 5:1, 10:1, 15:1 or 20:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0044] Preferably, the solvent comprises any one of methanol, ethanol or water or a combination of at least two thereof. Typical but non-limiting combinations include a combination of methanol and ethanol, a combination of ethanol and water, or a combination of methanol, ethanol and water.

[0045] Preferably, the mass ratio of the hydrogenation catalyst to succinonitrile is (0.1-10):1, for example, 0.1:1, 1:1, 3:1, 5:1 or 10:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0046] Preferably, the step of introducing hydrogen specifically comprises: introducing nitrogen into the autoclave for replacement, and then introducing hydrogen for replacement, the replacement pressure is 0.1-1MPa, for example, it can be 0.1MPa, 0.3MPa, 0.5MPa, 0.8MPa or 1MPa, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0047] Preferably, the stirring rate of the reaction is 400-800 rpm, for example, 400 rpm, 500 rpm, 600 rpm, 700 rpm or 800 rpm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0048] Preferably, the reaction temperature is 50-100°C, for example, 50°C, 60°C, 80°C, 90°C or 100°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0049] Preferably, the reaction pressure is 1-6 MPa, for example, 1 MPa, 2 MPa, 3 MPa, 5 MPa or 6 MPa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0050] Preferably, the reaction time is 0.5-3 h, for example, 0.5 h, 1 h, 1.5 h, 2 h or 3 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] (1) The preparation method of the hydrogenation catalyst provided by the present invention is to use γ-Al 2 O 3 As carrier, in γ-Al 2 O 3 The main active ingredient nickel oxide is loaded on the catalyst, and potassium oxide and / or lanthanum oxide are added. The prepared hydrogenation catalyst can be used for hydrogenating succinonitrile to prepare 1,4-butanediamine. The obtained hydrogenation catalyst is eggshell-type. Compared with the uniform catalyst, the hydrogenation catalyst exhibits high activity, high selectivity and stability in the hydrogenation reaction. At the same time, potassium and / or lanthanum metal elements are added during the preparation process, so that the catalyst has a higher specific surface area.

[0053] (2) The hydrogenation catalyst provided by the present invention is applied to the process of preparing 1,4-butanediamine by hydrogenating succinonitrile, which can greatly improve the selectivity of 1,4-butanediamine and reduce the formation of by-product tetrahydropyrrole. At the same time, the use of auxiliary alkali is avoided in the hydrogenation process, and the subsequent alkali removal operation is omitted in the hydrogenation process, which greatly reduces the operating difficulty of the hydrogenation process and facilitates industrial production. DETAILED DESCRIPTION

[0054] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0055] Example 1

[0056] This embodiment provides a hydrogenation catalyst, wherein the hydrogenation catalyst comprises γ-Al 2 O 3 and loaded on γ-Al 2 O 3 Nickel oxide, potassium oxide and lanthanum oxide on the surface; the preparation method of the hydrogenation catalyst comprises the following steps:

[0057] (1) Nickel nitrate, potassium nitrate, lanthanum nitrate and acetone are uniformly mixed, and the obtained active component acetone solution is mixed with γ-Al with a particle size of 3 mm. 2 O 3 Mixing, impregnating at 30° C. for 25 h, and then drying at 120° C. for 15 h to obtain a catalyst precursor;

[0058] In the active component acetone solution, the mass fraction of nickel nitrate is 4%, the mass fraction of potassium nitrate is 0.4%, and the mass fraction of lanthanum nitrate is 0.5%. 2 O 3 The mass ratio is 3:1;

[0059] (2) The catalyst precursor obtained in step (1) is calcined in a nitrogen atmosphere at 400° C. for 5 h and activated in a hydrogen atmosphere at 500° C. for 5 h to obtain the hydrogenation catalyst.

[0060] The hydrogenation catalyst is used to prepare 1,4-butanediamine, and the method for preparing 1,4-butanediamine comprises the following steps:

[0061] Succinonitrile is dissolved in ethanol, mixed with a hydrogenation catalyst and added into an autoclave, nitrogen is introduced into the autoclave for replacement 3 times, and hydrogen is introduced into the autoclave for replacement 3 times, and the replacement pressure is 0.5 MPa; the reaction is carried out at a stirring rate of 600 rpm, a temperature of 80° C., and a pressure of 3 MPa for 1 hour to obtain 1,4-butanediamine; the mass ratio of the ethanol to succinonitrile is 5:1; the mass ratio of the hydrogenation catalyst to succinonitrile is 5:1.

[0062] Example 2

[0063] This embodiment provides a hydrogenation catalyst, wherein the hydrogenation catalyst comprises γ-Al 2 O 3 And loaded on γ-Al 2 O 3 Nickel oxide, potassium oxide and lanthanum oxide on the surface; the preparation method of the hydrogenation catalyst comprises the following steps:

[0064] (1) Nickel nitrate, potassium nitrate, lanthanum nitrate and acetone are uniformly mixed, and the obtained active component acetone solution is mixed with γ-Al with a particle size of 2 mm. 2 O 3 Mixing, impregnating at 20° C. for 30 h, and then drying at 80° C. for 20 h to obtain a catalyst precursor;

[0065] In the active component acetone solution, the mass fraction of nickel nitrate is 3.5%, the mass fraction of potassium nitrate is 0.6%, and the mass fraction of lanthanum nitrate is 0.6%; the active component acetone solution and γ-Al 2 O 3 The mass ratio is 1:1;

[0066] (2) The catalyst precursor obtained in step (1) is calcined in an argon atmosphere at 300° C. for 8 h and activated in a hydrogen atmosphere at 300° C. for 8 h to obtain the hydrogenation catalyst.

[0067] The hydrogenation catalyst is used to prepare 1,4-butanediamine, and the method for preparing 1,4-butanediamine comprises the following steps:

[0068] Succinonitrile is dissolved in methanol, mixed with a hydrogenation catalyst and added into an autoclave, nitrogen is introduced into the autoclave for replacement 3 times, and hydrogen is introduced into the autoclave for replacement 3 times, and the replacement pressure is 0.1 MPa; the reaction is carried out at a stirring rate of 400 rpm, a temperature of 50° C., and a pressure of 6 MPa for 3 hours to obtain 1,4-butanediamine; the mass ratio of the methanol to succinonitrile is 0.1:1; the mass ratio of the hydrogenation catalyst to succinonitrile is 0.1:1.

[0069] Example 3

[0070] This embodiment provides a hydrogenation catalyst, wherein the hydrogenation catalyst comprises γ-Al 2 O 3 And loaded on γ-Al 2 O 3 Nickel oxide, potassium oxide and lanthanum oxide on the surface; the preparation method of the hydrogenation catalyst comprises the following steps:

[0071] (1) uniformly mixing nickel chloride, potassium phosphate, lanthanum chloride and acetone, the obtained active component acetone solution and γ-Al with a particle size of 4 mm 2 O 3 Mixing, impregnating at 50° C. for 20 h, and then drying at 140° C. for 10 h to obtain a catalyst precursor;

[0072] In the active component acetone solution, the mass fraction of nickel chloride is 5%, the mass fraction of potassium phosphate is 0.3%, and the mass fraction of lanthanum chloride is 0.3%; the active component acetone solution and γ-Al 2 O 3 The mass ratio is 3:0.3;

[0073] (2) The catalyst precursor obtained in step (1) is calcined in a helium atmosphere at 500° C. for 2 h and activated in a hydrogen atmosphere at 600° C. for 2 h to obtain the hydrogenation catalyst.

[0074] The hydrogenation catalyst is used to prepare 1,4-butanediamine, and the method for preparing 1,4-butanediamine comprises the following steps:

[0075] Succinonitrile is dissolved in water, mixed with a hydrogenation catalyst and added into an autoclave, nitrogen is introduced into the autoclave for replacement 3 times, and hydrogen is introduced into the autoclave for replacement 3 times, and the replacement pressure is 1 MPa; the reaction is carried out at a stirring rate of 800 rpm, a temperature of 100° C., and a pressure of 1 MPa for 0.5 h to obtain 1,4-butanediamine; the mass ratio of water to succinonitrile is 20:1; the mass ratio of the hydrogenation catalyst to succinonitrile is 10:1.

[0076] Example 4

[0077] This embodiment provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of Embodiment 1 is that, in the active component acetone solution of step (1), the mass fraction of nickel nitrate is adjusted to 0.1%, the mass fraction of potassium nitrate is adjusted to 1%, and the mass fraction of lanthanum nitrate is adjusted to 1%, and the rest is the same as that of Embodiment 1.

[0078] Example 5

[0079] This embodiment provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of Embodiment 1 is that, in the active component acetone solution of step (1), the mass fraction of nickel nitrate is adjusted to 10%, the mass fraction of potassium nitrate is adjusted to 0.1%, and the mass fraction of lanthanum nitrate is adjusted to 0.1%, and the rest is the same as that of Embodiment 1.

[0080] Example 6

[0081] This embodiment provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of Example 1 is that potassium nitrate is not added in step (1), and the rest is the same as that of Example 1.

[0082] Example 7

[0083] This embodiment provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of Example 1 is that lanthanum nitrate is not added in step (1), and the rest is the same as that of Example 1.

[0084] Example 8

[0085] This embodiment provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of embodiment 1 is that, except that the activation temperature in step (2) is adjusted to 250° C., the rest is the same as that of embodiment 1.

[0086] Example 9

[0087] This embodiment provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of Embodiment 1 is that, except that the activation temperature in step (2) is adjusted to 650° C., the rest is the same as that of Embodiment 1.

[0088] Example 10

[0089] This embodiment provides a hydrogenation catalyst, which is used to prepare 1,4-butanediamine. The method for preparing 1,4-butanediamine is different from that of Example 1 in that nitrogen is introduced into the autoclave for replacement once, and then hydrogen is introduced for replacement once, and the rest is the same as that of Example 1.

[0090] Embodiment 11

[0091] This embodiment provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of embodiment 1 is that the mass fraction of acetone in step (1) is replaced by methyl ethyl ketone, and the rest is the same as that of embodiment 1.

[0092] Example 12

[0093] This embodiment provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of embodiment 1 is that the mass fraction of acetone in step (1) is replaced by ethanol, and the rest is the same as that of embodiment 1.

[0094] Comparative Example 1

[0095] This comparative example provides a hydrogenation catalyst. The difference between the preparation method of the hydrogenation catalyst and that of Example 1 is that potassium nitrate and lanthanum nitrate are not added in step (1), the mass fraction of acetone is replaced by water, and the rest is the same as that of Example 1.

[0096] The hydrogenation catalysts provided in Examples 1-12 and Comparative Example 1 were used to prepare 1,4-butanediamine. After the reaction, the reaction solution was allowed to stand for stratification and the hydrogenation catalyst was removed by filtration to obtain a product. The content of 1,4-butanediamine in the product was analyzed by gas chromatography, and the conversion rate of succinonitrile and the selectivity of 1,4-butanediamine were calculated. The results are shown in Table 1.

[0097] Table 1

[0098] Succinonitrile conversion rate / % 1,4-Butanediamine selectivity / % Example 1 99.9 99.3 Example 2 99.2 98.9 Example 3 99.7 98.5 Example 4 98.3 97.2 Example 5 98.6 96.5 Example 6 99.0 98.9 Example 7 99.2 98.7 Example 8 99.4 98.7 Example 9 90.1 88.1 Example 10 88.2 89.3 Embodiment 11 98.1 97.8 Example 12 97.6 96.9 Comparative Example 1 93.2 90.1

[0099] It can be seen from Table 1 that the hydrogenation catalyst provided by the present invention is used to prepare 1,4-butanediamine, and the conversion rate of succinonitrile and the selectivity of 1,4-butanediamine are relatively high;

[0100] From the comparison of Examples 1-5, it can be seen that when the ratio of the active component is within the preferred range, the conversion rate of succinonitrile and the selectivity of 1,4-butanediamine in the preparation of 1,4-butanediamine are relatively high. When the ratio exceeds the preferred range, the selectivity of 1,4-butanediamine will be reduced. From the comparison of Example 1 with Examples 6 and 7, it can be seen that when a single auxiliary active component is added during the preparation of the hydrogenation catalyst, a relatively high conversion rate of succinonitrile and selectivity of 1,4-butanediamine can also be obtained. From the comparison of Example 1 with Examples 8 and 9, it can be seen that when the activation temperature is too low or too high, the conversion rate of succinonitrile and the selectivity of 1,4-butanediamine can also be reduced. It will have an adverse effect on the conversion rate of succinonitrile and the selectivity of 1,4-butanediamine; from the comparison between Example 1 and Example 10, it can be seen that the nitrogen is introduced only once for replacement, and the hydrogen is introduced only once for replacement, which is not conducive to creating a good environmental atmosphere for hydrogenating succinonitrile to prepare 1,4-butanediamine, thereby affecting the conversion rate of succinonitrile and the selectivity of 1,4-butanediamine; from the comparison between Example 1 and Examples 11 and 12, it can be seen that when methyl ethyl ketone and ethanol are used as solvents, the conversion rate of succinonitrile and the selectivity of 1,4-butanediamine are reduced compared with acetone as a solvent.

[0101] From the comparison between Example 1 and Comparative Example 1, it can be seen that using water as a solvent without adding potassium salt and lanthanum salt will lead to a significant decrease in the selectivity of 1,4-butanediamine.

[0102] In summary, the preparation method of the hydrogenation catalyst provided by the present invention is based on γ-Al 2 O 3 As carrier, in γ-Al 2 O 3 The main active ingredient nickel oxide is loaded on the catalyst, and potassium oxide and / or lanthanum oxide are added. The prepared hydrogenation catalyst can be used for hydrogenating succinonitrile to prepare 1,4-butanediamine. The obtained hydrogenation catalyst is eggshell-type. Compared with the uniform catalyst, the hydrogenation catalyst exhibits high activity, high selectivity and stability in the hydrogenation reaction. At the same time, potassium and / or lanthanum metal elements are added during the preparation process, so that the catalyst has a higher specific surface area.

[0103] The hydrogenation catalyst provided by the present invention is applied to the process of preparing 1,4-butanediamine by hydrogenating succinonitrile, which can greatly improve the selectivity of 1,4-butanediamine and reduce the generation of by-product tetrahydropyrrole. At the same time, the use of auxiliary alkali is avoided in the hydrogenation process, and the subsequent alkali removal operation of the hydrogenation process is omitted, which greatly reduces the operating difficulty of the hydrogenation process and is convenient for industrial production.

[0104] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a hydrogenation catalyst, characterized in that: The preparation method comprises the following steps: (1) uniformly mixing nickel salt, catalytic metal salt and solvent, mixing the obtained active component solution with γ-Al2O3 for impregnation, and drying to obtain a catalyst precursor; (2) The catalyst precursor obtained in step (1) is calcined and activated in sequence to obtain the hydrogenation catalyst.

2. The preparation method according to claim 1, characterized in that: The catalytic promoter metal salt in step (1) includes potassium salt and / or lanthanum salt; Preferably, the potassium salt comprises potassium nitrate and / or potassium phosphate; Preferably, the lanthanum salt comprises lanthanum nitrate and / or lanthanum chloride; Preferably, the nickel salt in step (1) comprises nickel nitrate and / or nickel chloride; Preferably, in the active component solution of step (1), the mass fraction of nickel salt is 0.1-10%, the mass fraction of potassium salt is ≤1%, and the mass fraction of lanthanum salt is ≤1%; Preferably, in the active component solution of step (1), the mass fraction of nickel salt is 3.5-5%, the mass fraction of potassium salt is 0.3-0.6%, and the mass fraction of lanthanum salt is 0.3-0.6%; Preferably, the solvent in step (1) comprises any one of acetone, methyl ethyl ketone or ethanol, or a combination of at least two thereof, preferably acetone.

3. The preparation method according to claim 1 or 2, characterized in that: The mass ratio of the active component solution to γ-Al2O3 in step (1) is (1-3):(0.3-1); Preferably, the particle size of the γ-Al2O3 in step (1) is 2-4 mm.

4. The preparation method according to any one of claims 1 to 3, characterized in that The immersion temperature in step (1) is 20-50° C. Preferably, the immersion time in step (1) is 20-30 hours; Preferably, the drying temperature in step (1) is 80-140°C; Preferably, the drying time in step (1) is 10-20 hours.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The calcination temperature in step (2) is 300-500°C; Preferably, the calcination time in step (2) is 2-8 hours; Preferably, the calcination in step (2) is carried out in a protective atmosphere; Preferably, the activation temperature in step (2) is 300-600°C; Preferably, the activation time in step (2) is 2-8 hours; Preferably, the activation in step (2) is carried out in a hydrogen atmosphere.

6. A hydrogenation catalyst, characterized in that The hydrogenation catalyst is prepared by the method for preparing the hydrogenation catalyst according to any one of claims 1 to 5, and the hydrogenation catalyst comprises γ-Al2O3 and nickel oxide and a catalytic metal oxide supported on the γ-Al2O3.

7. The hydrogenation catalyst according to claim 6, characterized in that The catalytic promoter metal oxide includes potassium oxide and / or lanthanum oxide.

8. Use of the hydrogenation catalyst as claimed in claim 6 or 7, characterized in that: The hydrogenation catalyst is used to prepare 1,4-butanediamine, and the method for preparing 1,4-butanediamine comprises the following steps: Succinonitrile is dissolved in a solvent, mixed with a hydrogenation catalyst, and then hydrogen is introduced to react to obtain 1,4-butanediamine.

9. The use according to claim 8, characterized in that: The mass ratio of the solvent to succinonitrile is (0.1-20):1; Preferably, the solvent comprises any one of methanol, ethanol or water or a combination of at least two thereof; Preferably, the mass ratio of the hydrogenation catalyst to succinonitrile is (0.1-10):

1.

10. The use according to claim 8 or 9, characterized in that: The step of introducing hydrogen specifically comprises: introducing nitrogen into the autoclave for replacement, and then introducing hydrogen for replacement, with the replacement pressure being 0.1-1 MPa; Preferably, the stirring rate of the reaction is 400-800 rpm; Preferably, the reaction temperature is 50-100°C; Preferably, the reaction pressure is 1-6 MPa; Preferably, the reaction time is 0.5-3h.