Methods for hydrogenating butadiene

Abstract

This invention relates to the field of selective hydrogenation of C4 fractions to 1-butene, and discloses a method for hydrogenating butadiene. The method includes: contacting a butadiene-containing material with a catalyst under hydrogenation conditions. The catalyst comprises a support and a metal active component supported on the support. The metal active component includes a first metal active component and an optional second metal active component. The first metal active component is Cu, and the second metal active component is selected from at least one transition metal other than Cu. The support is carbon-modified alumina microspheres. Using the method of this invention, a high conversion rate of 1,3-butadiene and high selectivity for 1-butene can be obtained.

Description

Technical Field

[0001] This invention relates to the field of selective hydrogenation of C4 fractions to produce 1-butene, and more specifically to a method for hydrogenating butadiene. Background Technology

[0002] Alumina-supported catalysts are widely used in petrochemical plants. Industrial alumina supports are generally processed into sheets, strips, or spheres. Among these, spherical alumina can be uniformly packed in a fixed bed in a point-contact manner, reducing column or bed resistance, and therefore has been widely used. Currently, commonly used methods for preparing γ-alumina microspheres include oil column forming and spray drying. However, traditional alumina microsphere preparation methods have poor controllability, generally only yielding alumina microspheres with particle sizes below 100 μm or above 1000 μm, and the resulting microspheres suffer from problems such as uneven particle size distribution and low sphericity.

[0003] Microfluidics, centered on microstructured components, enhances mixing and transport within confined spaces by reducing the dispersion scale, resulting in a controllable and efficient process. Microchannels are widely used in droplet preparation processes, producing droplets with uniform and controllable sizes. Combining UV and temperature-based curing initiation methods, microspheres can be further obtained. However, the production capacity of a single microchannel is very low. For example, the yield of alumina microspheres prepared using a coaxial loop microchannel is only 1 g / h, which cannot meet the needs of industrial applications. Multi-channel microchannel reactors can solve the production efficiency problem. Taking an 8-channel reactor as an example, the continuous phase fluid and dispersed phase fluid flow through a dendritic fluid distributor, dispersing into eight independent fluid streams. These streams then flow into eight identical T-shaped channels to complete the shearing process of the dispersed phase, generating droplets. The droplets generated in each channel eventually converge at the central outlet and flow out. After passing through a hot oil bath, the droplets solidify into gel microspheres, which are then dried and calcined to obtain alumina microspheres.

[0004] When the main components of the C4 raffinate are butene and butane, with a small amount of butadiene, it is necessary to remove the butadiene before separating the butene and butane. Current technology typically uses hydrogenation catalysts to hydrogenate the C4 raffinate to remove the butadiene. In existing technologies, the hydrogenation reaction of 1,3-butadiene in the C4 raffinate mostly uses Pd / Al2O3 catalysts. However, this catalyst has the following problems: First, it uses a precious metal as the active component, resulting in high cost; second, the acidity of the alumina support itself leads to a side reaction during diene hydrogenation, where diene polymerizes into a polymer, known industrially as "green oil." This polymer can adhere to the catalyst surface, affecting catalyst activity and clogging pores, reducing the catalyst's diffusion performance and further decreasing its reactivity; third, the catalyst has poor selectivity, as it hydrogenates butene to form butane while hydrogenating butadiene, thus losing the effective components in the C4 raffinate.

[0005] Therefore, there is an urgent need to find a method that can reduce butene loss while removing butadiene from C4 raffinate. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of low butadiene removal rate and low butene selectivity in the existing technology, and to provide a method for hydrogenating butadiene.

[0007] To achieve the above objectives, the present invention provides a method for hydrogenating butadiene, the method comprising: contacting a butadiene-containing material with a catalyst under hydrogenation conditions, the catalyst comprising a support and a metal active component supported on the support, the metal active component comprising a first metal active component and an optional second metal active component, the first metal active component being Cu, the second metal active component being selected from at least one transition metal other than Cu, and the support being carbon-modified alumina microspheres.

[0008] The method of this invention can achieve a high conversion rate of 1,3-butadiene and a high selectivity for 1-butene in the hydrogenation reaction of 1,3-butadiene in the C4 raffinate. Attached Figure Description

[0009] Figure 1 These are scanning electron microscope images of the alumina microspheres prepared in the preparation example.

[0010] Figure 2 This is a particle size distribution diagram of the alumina microspheres prepared in the preparation example. Detailed Implementation

[0011] 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.

[0012] In this invention, unless otherwise specified, the diameter of the alumina microspheres refers to the average diameter of the alumina microspheres.

[0013] This invention provides a method for hydrogenating butadiene, the method comprising: contacting a butadiene-containing material with a catalyst under hydrogenation conditions, the catalyst comprising a support and a metal active component supported on the support, the metal active component comprising a first metal active component and optionally a second metal active component, the first metal active component being Cu, the second metal active component being selected from at least one transition metal other than Cu (preferably Ni, Co, Pt, Pd, Rh, Ru, Mn, Co, and Ag), and the support being carbon-modified alumina microspheres.

[0014] According to the present invention, preferably, the contact conditions include: a temperature of 30°C-60°C, a hydrogen pressure of 0.6-3.5 MPa, and a liquid hourly space velocity (LHSV) of 10-60 h⁻¹ for the butadiene-containing material. -1 The molar ratio of hydrogen to alkynes in butadiene-containing materials is 0.2-10.

[0015] According to the present invention, preferably, the total butadiene content in the butadiene-containing material is greater than or equal to 0.5% by volume, more preferably 0.5-3% by volume, and more preferably 1-2% by volume.

[0016] According to the present invention, preferably, the butadiene-containing material contains at least one of butane, butene, butadiene, and alkyne; more preferably, the alkyne includes at least one of methylacetylene, ethylacetylene, and vinylacetylene.

[0017] According to the present invention, preferably, the total content of alkynes in the butadiene-containing material is less than or equal to 0.05% by volume.

[0018] According to the present invention, preferably, the total butene content in the butadiene-containing material is greater than or equal to 70% by volume, more preferably 70-90% by volume. More preferably, the butene includes at least one selected from trans-2-butene, 1-butene, isobutene, and cis-2-butene.

[0019] According to the present invention, preferably, the butadiene-containing material is C4 raffinate.

[0020] According to the present invention, preferably, the weight ratio of the first metal active component and the second metal active component, calculated as metal elements, is 100-800 (for example, it can be 100, 130, 200, 220, 250, 300, 500, 700, 715, 750, or 800).

[0021] According to the present invention, preferably, the first metal active component is Cu, and the second metal active component is Pd.

[0022] According to the present invention, preferably, the preparation method of the catalyst includes: contacting alumina microspheres with a nitrogen-containing polymer solution, then subjecting the contact product to a first calcination under an inert atmosphere to obtain a support, and then loading the metal active component onto the support.

[0023] According to the present invention, preferably, the alumina microspheres have a particle diameter of 200-800 μm and a coefficient of variation of 3-8%.

[0024] According to the present invention, the source of the alumina microspheres is not particularly limited, as long as the particle diameter and coefficient of variation of the alumina microspheres meet the defined range. The alumina microspheres can be prepared according to methods described in the literature, for example, according to the methods described in CN110203953B or CN110282642B. 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.

[0025] In the method for preparing alumina microspheres according to the present invention, preferably, the aluminum sol has a solid content of 5-8 wt%.

[0026] In the method for preparing alumina microspheres according to the present invention, preferably, the organic solvent used in the preparation of alumina microspheres is a C1-C10 monohydric saturated alcohol, preferably octanol.

[0027] In the method for preparing alumina microspheres according to the present invention, the drying temperature can be 100-120℃ and the drying time can be 3-15h.

[0028] In the method for preparing alumina microspheres according to the present invention, the calcination temperature can be 550-1200℃, and the calcination time can be 4-10h.

[0029] According to the present invention, preferably, the alumina microspheres are prepared in a microchannel reactor. There is no particular limitation on the type of microchannel reactor; the microchannel reactor may be a single-channel reactor and / or a multi-channel reactor.

[0030] According to a further preferred embodiment of the present invention, the multi-channel reactor is an eight-channel reactor. 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 point 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 distributed 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.

[0031] 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. The flow rate of the dispersed phase is then adjusted to 1-4 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.

[0032] In the method for preparing the catalyst according to the present invention, the amount of the nitrogen-containing polymer can be selected within a wide range. Preferably, the amount of the nitrogen-containing polymer solution, calculated as nitrogen-containing polymer, is 0.1-1g relative to 100g of alumina microspheres, more preferably 0.9-1g.

[0033] In the method for preparing the catalyst according to the present invention, the contact conditions between the alumina microspheres and the nitrogen-containing polymer solution can be selected within a wide range. Preferably, the contact temperature between the alumina microspheres and the nitrogen-containing polymer solution is 100-120°C, and the contact time is 4-10 h, preferably 8-10 h.

[0034] In the method for preparing the catalyst according to the present invention, the type of nitrogen-containing polymer can be selected from a wide range. Preferably, the nitrogen-containing polymer in the nitrogen-containing polymer solution is a polymer containing a nitrogen heterocycle, preferably at least one of polyvinylimidazole, polyvinylpyridine, and polyvinylpyrrolidone, and more preferably polyvinylimidazole.

[0035] In the method for preparing the catalyst according to the present invention, the concentration of the nitrogen-containing polymer in the nitrogen-containing polymer solution is not particularly limited, but preferably, the concentration of the nitrogen-containing polymer in the nitrogen-containing polymer solution is 0.1-1 wt%, more preferably 0.9-1 wt%.

[0036] In the method for preparing the catalyst according to the present invention, preferably, the solvent in the nitrogen-containing polymer solution is an alcohol, preferably a C1-C4 saturated alcohol, and more preferably methanol and / or ethanol.

[0037] In the method for preparing the catalyst according to the present invention, the conditions for the first calcination can be selected within a wide range. Preferably, the temperature of the first calcination is 400-800℃, more preferably 400-450℃, and the time is 2-10h, more preferably 9-10h.

[0038] In the method for preparing the catalyst according to the present invention, the inert atmosphere used in the first calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0039] According to the present invention, preferably, the preparation method of the catalyst further includes first drying the product after contacting alumina microspheres with a nitrogen-containing polymer solution and then performing a first calcination. More preferably, the temperature of the first drying is 60-80°C and the time is 4-12 hours.

[0040] In the method for preparing the catalyst according to the present invention, preferably, the amount of the metal active component, calculated as metal element, is 2-8g relative to 20g of support, more preferably 2.2-5.72g.

[0041] In the method for preparing the catalyst according to the present invention, the metal active component can be loaded onto the support by a single calcination. Therefore, preferably, the metal active component is loaded onto the support by contacting the support with an impregnation solution containing the metal active component, followed by a second calcination under an inert atmosphere.

[0042] In the method for preparing the catalyst according to the present invention, preferably, the conditions for the second calcination include: a temperature of 400-800°C and a time of 2-10 h.

[0043] In the method for preparing the catalyst according to the present invention, the inert atmosphere used in the second calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0044] According to the present invention, preferably, the preparation method of the catalyst further includes contacting the impregnation liquid containing the metal active component with the support, subjecting the product to a second drying and then a second calcination; more preferably, the temperature of the second drying is 100-130°C and the time is 4-12h.

[0045] In the method for preparing the catalyst according to the present invention, preferably, the conditions for contacting the impregnation solution containing the metal active component with the support include impregnation at 15-40°C for 0.2-1 h.

[0046] In the method for preparing the catalyst according to the present invention, preferably, the impregnation solution containing the metal active component is prepared by dissolving a water-soluble salt of the metal in water.

[0047] More preferably, the copper salt solution in the impregnation solution containing the metal active component has a mass percentage content of 10-40 wt%.

[0048] In the method for preparing the catalyst according to the present invention, the metal active component can also be loaded onto the support by means of two calcinations. Therefore, preferably, the metal active component is loaded onto the support by: contacting the support with a first part of the solution containing the metal active component, and then performing a first-stage calcination under an inert atmosphere; and contacting the first-stage calcination product with a second part of the solution containing the metal active component, and then performing a second-stage calcination under an inert atmosphere.

[0049] In the method for preparing the catalyst according to the present invention, preferably, the metal active component in the first portion of the solution containing the metal active component is Cu.

[0050] In the method for preparing the catalyst according to the present invention, preferably, the metal active component in the second part of the solution containing the metal active component is Pd.

[0051] In the method for preparing the catalyst according to the present invention, preferably, the solution containing the metal active component is prepared by dissolving a water-soluble salt of a metal in water.

[0052] More preferably, the mass percentage of copper salt solution in the first portion of the solution containing the metal active component is 10-30 wt%.

[0053] More preferably, the mass percentage of palladium salt solution in the second part of the solution containing the metal active component is 0.05-0.1 wt%.

[0054] In the method for preparing the catalyst according to the present invention, preferably, the first part of the solution containing the metal active component is contacted with the support by impregnation and / or spraying.

[0055] In the method for preparing the catalyst according to the present invention, preferably, the conditions for impregnating the support with the first part of the solution containing the metal active component include impregnation at 15-40°C for 0.2-1 h; more preferably, the support is impregnated with the first part of the solution containing the metal active component, and the impregnated product is dried at 100-140°C for 10-15 h, and then subjected to a first-stage calcination under an inert atmosphere.

[0056] In the method for preparing the catalyst according to the present invention, preferably, the conditions for spraying the support with the first portion of the solution containing the metal active component include spraying at 15-40°C for 0.2-1 h. More preferably, the support is sprayed with the first portion of the solution containing the metal active component, the sprayed product is placed in air for 1-3 h, dried at 100-140°C for 10-15 h, and then subjected to a first-stage calcination under an inert atmosphere.

[0057] In the method for preparing the catalyst according to the present invention, preferably, the conditions for the first-stage calcination include: a temperature of 400-800°C and a time of 2-10 h.

[0058] In the method for preparing the catalyst according to the present invention, preferably, the contact between the second part of the solution containing the metal active component and the primary calcination product is by impregnation and / or spraying.

[0059] In the method for preparing the catalyst according to the present invention, preferably, the conditions for impregnating the first-stage calcined product with the second part of the solution containing the metal active component include impregnation at 15-40°C for 0.2-1 h; more preferably, the first-stage calcined product is impregnated with the second part of the solution containing the metal active component, and the impregnated product is dried at 100-140°C for 10-15 h, and then subjected to a second-stage calcination under an inert atmosphere.

[0060] In the method for preparing the catalyst according to the present invention, preferably, the conditions for spraying the first-stage calcined product with the second part of the solution containing the metal active component include spraying at 15-40°C for 0.2-1 h; more preferably, the first-stage calcined product is sprayed with the second part of the solution containing the metal active component, and the sprayed product is placed in air for 1-3 h, dried at 100-140°C for 10-15 h, and then subjected to a second-stage calcination under an inert atmosphere.

[0061] In the method for preparing the catalyst according to the present invention, preferably, the conditions for the secondary calcination include: a temperature of 400-800°C and a time of 2-10 h.

[0062] In the method for preparing the catalyst according to the present invention, preferably, the inert atmosphere used in the primary roasting and secondary roasting is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0063] The present invention will be described in detail below through embodiments. In the following embodiments,

[0064] The room temperature is approximately 25°C.

[0065] The diameter of the alumina microspheres was measured using scanning electron microscopy.

[0066] The method for testing the coefficient of variation is as follows: the number of alumina microspheres in a unit area is measured by scanning electron microscopy, and the diameter of each alumina microsphere is measured. Then, the coefficient of variation is calculated according to the formula.

[0067] The coefficient of variation is calculated using the following formula:

[0068]

[0069] CV: Coefficient of variation, n: Alumina microsphere count, X i Diameter of a single alumina microsphere. Average diameter of all alumina microspheres.

[0070]

[0071]

[0072] Preparation Example

[0073] The dispersed phase was an aluminum sol 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 1 and flow into the droplet generation layer, then outflow from the outlet. The continuous phase flow rate was eventually stabilized at 6-10 mL / min. Then, the dispersed phase flow rate was adjusted to 1-4 mL / min to fill the dispersed phase distribution layer 4 and flow into the droplet generation layer, where droplets were further generated 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 a diameter of 345 μm and a coefficient of variation of 7.2% were obtained.

[0074] The scanning electron microscope image of the alumina microspheres is shown below. Figure 1 As shown, the alumina microspheres have a diameter in the range of 300-400 μm and are uniformly spherical particles.

[0075] The particle size distribution diagram of the alumina microspheres is shown below. Figure 2 As shown, by Figure 2 It can be seen that the particle size distribution range of alumina microspheres is very narrow.

[0076] Example 1

[0077] (1) 100g of alumina microspheres obtained in the preparation example were immersed in an ethanol solution of polyvinyl imidazole with a concentration of 1wt% (where the amount of polyvinyl imidazole was 1g), and then transferred to a hydrothermal reactor and reacted at 100°C for 10h. After cooling and filtration, the mixture was dried at 80°C for 4h, and then placed in a nitrogen atmosphere and calcined at 400°C for 10h to obtain the support (carbon-doped alumina microspheres).

[0078] (2) Place 20 g of support in a 10 wt% copper nitrate aqueous solution (of which the amount of copper nitrate, calculated as metal element, is 2.2 g), immerse at room temperature for 20 min, remove the support, drain, dry at 120 °C for 12 h, and calcine at 400 °C for 3 h in a nitrogen atmosphere to obtain the catalyst.

[0079] XRF characterization showed that the copper loading in the catalyst was 9.9 wt%.

[0080] Example 2

[0081] Step (1) is the same as in Example 1.

[0082] (2) At room temperature, 20 g of support was sprayed with 16 wt% copper nitrate aqueous solution (of which the amount of copper nitrate as metal element was 3.52 g) for 0.5 h, placed in air for 2 h, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h under nitrogen protection to obtain the catalyst.

[0083] XRF characterization showed that the copper loading in the catalyst was 14.9 wt%.

[0084] Example 3

[0085] Step (1) is the same as in Example 1.

[0086] (2) Place 20 g of the carrier in a 10 wt% copper nitrate aqueous solution (of which the amount of copper nitrate calculated as metal element is 2.2 g), immerse it at room temperature for 20 min, remove the carrier, drain it, dry it at 120 °C for 12 h, and calcine it at 400 °C for 3 h in a nitrogen atmosphere to obtain the first-stage calcined product.

[0087] (3) The primary calcined product obtained in step (2) was placed in a 0.1 wt% palladium nitrate aqueous solution (in which the amount of palladium nitrate calculated as metal element was 0.016 g), immersed at room temperature for 20 min, then removed from the support, drained, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h in a nitrogen atmosphere to obtain the catalyst.

[0088] XRF characterization showed that the catalyst contained 9.9 wt% copper and 0.07 wt% palladium.

[0089] Example 4

[0090] Step (1) is the same as in Example 1.

[0091] (2) At room temperature, 20 g of carrier was sprayed with a 16 wt% copper nitrate aqueous solution (of which the amount of copper nitrate as metal element was 3.52 g) for 0.5 h, placed in air for 2 h, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h under nitrogen protection to obtain the first-stage calcined product.

[0092] (3) At room temperature, the primary calcined product obtained in step (2) was sprayed with a 0.1 wt% palladium nitrate aqueous solution (in which the amount of palladium nitrate, calculated as metal element, was 0.016 g) for 0.5 h, placed in air for 2 h, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h under nitrogen protection to obtain the catalyst.

[0093] XRF characterization showed that the catalyst contained 9.8 wt% copper and 0.07 wt% palladium.

[0094] Example 5

[0095] Step (1) is the same as in Example 1.

[0096] (2) At room temperature, 20 g of carrier was sprayed with a 26 wt% copper nitrate aqueous solution (of which the amount of copper nitrate as metal element was 5.72 g) for 0.5 h, placed in air for 2 h, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h under nitrogen protection to obtain the first-stage calcined product.

[0097] (3) At room temperature, the primary calcined product obtained in step (2) was sprayed with a 0.05wt% palladium nitrate aqueous solution (in which the amount of palladium nitrate, calculated as metal element, was 0.008g) for 0.5h, placed in air for 2h, dried at 120℃ for 12h, and calcined at 400℃ for 3h under nitrogen protection to obtain the catalyst.

[0098] XRF characterization showed that the catalyst contained 22.2 wt% copper and 0.03 wt% palladium.

[0099] Comparative Example 1

[0100] The catalyst was prepared according to the method in Example 3, except that alumina microspheres were used directly as the carrier.

[0101] XRF characterization showed that the catalyst contained 9.9 wt% copper and 0.07 wt% palladium.

[0102] Comparative Example 2

[0103] The catalyst was prepared according to the method of Example 4, except that alumina microspheres were used directly as the carrier.

[0104] XRF characterization showed that the catalyst contained 9.8 wt% copper and 0.07 wt% palladium.

[0105] Comparative Example 3

[0106] The catalyst was prepared according to the method in Example 5, except that alumina microspheres were used directly as the carrier.

[0107] XRF characterization showed that the catalyst contained 22.2 wt% copper and 0.03 wt% palladium.

[0108] Test case

[0109] Catalyst evaluation was conducted in a two-stage fixed-bed reactor (Stage I and Stage II). Each stage was loaded with 20 mL of catalyst. After nitrogen purging, the C4 fraction was mixed with hydrogen and introduced into the reactor. The metered C4 feedstock was mixed with metered hydrogen and sequentially fed into Stage I and Stage II reactors from the bottom. The reaction products flowed out from the top of the reactor into a product storage tank. The catalyst was purged with nitrogen before the reaction and then reduced with hydrogen at 150°C for 2 h. The composition of the C4 fraction is shown in Table 1. The evaluation reaction time was 100 h, and the reaction conditions and test results are shown in Table 2. The content of each component in the C4 fraction and hydrogenation products was determined by gas chromatography.

[0110] Table 1

[0111] Components Content (volume %) Components Content (volume %) Isobutane 1.86 1,2-Butadiene 0.004 n-Butane 14.32 1,3-Butadiene 1.92 trans-2-butene 18.33 Methylacetylene - 1-Butene 16.52 Ethylacetylene 0.024 Isobutylene 35.87 Vinylacetylene 0.006 cis-2-butene 11.06

[0112] Table 2

[0113]

[0114] As can be seen from the results in Table 2, compared with the comparative examples, the catalysts in Examples 1-5 achieve higher butadiene conversion and butene selectivity when removing butadiene from the C4 fraction. In particular, the catalysts in Examples 4-5 yield even more significant results.

[0115] 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 hydrogenating butadiene, characterized in that, The method includes: contacting a butadiene-containing material with a catalyst under hydrogenation conditions, the catalyst comprising a support and a metal active component supported on the support, the metal active component comprising a first metal active component and an optional second metal active component, the first metal active component being Cu, the second metal active component being selected from at least one transition metal other than Cu, and the support being carbon-modified alumina microspheres; The amount of the nitrogen-containing polymer solution used relative to 100g of alumina microspheres is 0.1-1g, calculated as a nitrogen-containing polymer; the nitrogen-containing polymer in the nitrogen-containing polymer solution is at least one of polyvinylimidazolium, polyvinylpyridine, and polyvinylpyrrolidone. The total butadiene content in the butadiene-containing material is 0.5-3% by volume. The total alkyne content in the butadiene-containing material is less than or equal to 0.05% by volume. The total butadiene content in the butadiene-containing material is greater than or equal to 70% by volume. The catalyst preparation method includes: contacting alumina microspheres with a nitrogen-containing polymer solution, then calcining the contact product under an inert atmosphere to obtain a support, and then loading the metal active component onto the support; The contact conditions between the butadiene-containing material and the catalyst include: a temperature of 30℃-60℃, a hydrogen pressure of 0.6-3.5 MPa, and a liquid hourly space velocity (LHSV) of 10-60 h⁻¹ for the butadiene-containing material. -1 The molar ratio of hydrogen to alkynes in butadiene-containing materials is 0.2-10.

2. The method according to claim 1, wherein, The butadiene-containing material contains at least one of butane, butene, butadiene, and alkyne.

3. The method according to claim 1, wherein, The alkyne includes at least one of methylacetylene, ethylacetylene, and vinylacetylene.

4. The method according to claim 1, wherein, The total butene content in the butadiene-containing material is 70-90% by volume.

5. The method according to claim 1, wherein, The butadiene-containing material is C4 raffinate; And / or, the weight ratio of the first metal active component (calculated as a metal element) to the second metal active component (calculated as a metal element) is 100-800; And / or, the first metal active component is Cu, and the second metal active component is Pd.

6. The method according to claim 1, wherein, The alumina microspheres have a particle diameter of 200-800 μm and a coefficient of variation of 3-8%.

7. The method according to claim 1, wherein, The alumina microspheres are in contact with the nitrogen-containing polymer solution at a temperature of 100-120℃ for 4-10 hours.

8. The method according to claim 1, wherein, The nitrogen-containing polymer in the nitrogen-containing polymer solution is a polymer containing a nitrogen heterocycle; And / or, the concentration of the nitrogen-containing polymer in the nitrogen-containing polymer solution is 0.1-1 wt%; And / or, the solvent in the nitrogen-containing polymer solution is an alcohol.

9. The method according to claim 1, wherein, The nitrogen-containing polymer in the nitrogen-containing polymer solution is polyvinylimidazole.

10. The method according to claim 1, wherein, The solvent in the nitrogen-containing polymer solution is a C1-C4 saturated alcohol.

11. The method according to claim 1, wherein, The solvent in the nitrogen-containing polymer solution is methanol and / or ethanol.

12. The method according to claim 1, wherein, The first roasting temperature is 400-800℃, and the time is 2-10h; And / or, the inert atmosphere used in the first roasting process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

13. The method according to claim 1, wherein, The amount of the metal active component, calculated as metal element, is 2-8g relative to 20g of carrier.

14. The method according to claim 1, wherein, The amount of the metal active component, calculated as metal element, is 2.2-5.73g relative to 20g carrier.

15. The method according to claim 1, wherein, The method for loading the metal active component onto the support is as follows: the first part of the solution containing the metal active component is contacted with the support, and then a first-stage calcination is performed under an inert atmosphere; the second part of the solution containing the metal active component is contacted with the first-stage calcination product, and then a second-stage calcination is performed under an inert atmosphere.

16. The method according to claim 15, wherein, The active metal component in the first part of the solution containing the active metal component is Cu; And / or, the metal active component in the second part of the solution containing the metal active component is Pd; And / or, the carrier is contacted by immersion and / or spraying using a solution containing the first metal active component; And / or, the method of contacting the primary calcined product with the solution containing the second metal active component is impregnation and / or spraying.

17. The method according to claim 15, wherein, The conditions for the first-stage roasting include: a temperature of 400-800℃ and a time of 2-10 hours; And / or, the conditions for the secondary calcination include: a temperature of 400-800℃ and a time of 2-10h; And / or, the inert atmosphere used in the primary and secondary roasting is at least one of nitrogen, argon and helium atmospheres.

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