Process for the hydrodeethylenation of a c4 cut

Abstract

The present application relates to carbon four fraction hydrogenation acetylene removal technical field, disclose a kind of carbon four fraction hydrogenation acetylene removal method.The method includes: under hydrogenation condition, make carbon four fraction with catalyst contact, the catalyst includes carrier and the metal active component supported on carrier, the metal active component includes first metal active component and optional second metal active component, the first metal active component is Cu, the second metal active component is selected from at least one of Ni, Co, Pt, Pd, Rh, Ru, Mn, Co and Ag, and the carrier is carbon modified alumina microsphere.When carbon four fraction hydrogenation acetylene removal is carried out using the method of the present application, higher acetylene removal rate can be obtained while ensuring the lowest butadiene loss rate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of carbon four fraction hydrogenation acetylene removal, in particular to a method for carbon four fraction hydrogenation acetylene removal. BACKGROUND

[0002] Alumina supported catalyst has been widely used in petroleum chemical plants. The industrial alumina carrier generally needs to be processed into sheet, strip, spherical and the like, among which the spherical alumina can be uniformly stacked in the fixed bed in the form of point contact, reducing the column or bed resistance, and thus has been widely applied. At present, the commonly used preparation methods of gamma-alumina microspheres include oil column forming method, spray drying method and the like. However, the conventional alumina microsphere preparation method has poor controllability, and generally can only obtain alumina microspheres with particle size below 100 μm or above 1000 μm, and the obtained microspheres have problems of uneven particle size distribution and low ball forming rate.

[0003] Microfluidic technology takes micro-structure components as the core, and strengthens mixing and transmission by reducing the dispersion scale in a confined space, and the process is controllable and efficient. Microchannels are widely used in droplet preparation process, and the prepared droplets are uniform and controllable in size, and can be further obtained into microspheres by combining ultraviolet, temperature and other solidification initiation modes. However, the production capacity of a single microchannel is very low, for example, the yield of alumina microspheres prepared by a coaxial annular microchannel is only 1 g / h, which cannot meet the demand of industrial application. The multi-channel microchannel reactor can solve the problem of production efficiency. For example, 8 channels, the continuous phase fluid and the dispersed phase fluid are dispersed into 8 independent fluids after flowing through the tree-shaped fluid distributor, and then flow into 8 identical T-shaped channels to complete the shearing process of the dispersed phase to generate droplets. The droplets generated in each channel finally converge to the center outlet and flow out. The droplets flow through the hot oil bath to complete the solidification into gel microspheres, and then the alumina microspheres are obtained after drying and calcination.

[0004] The selective hydrogenation of carbon four fraction to remove acetylene is to convert the acetylenes such as methylacetylene, ethylacetylene and vinylacetylene in the carbon four fraction into butadiene, butene and a small amount of butane by using a selective hydrogenation catalyst through hydrogenation reaction. This method can selectively remove acetylenes in the carbon four fraction and simplify the butadiene separation process. However, the hydrogenation catalyst in the prior art not only removes acetylenes but also loses a large amount of butadiene when used for hydrogenation of carbon four fraction to remove acetylenes. Therefore, it is urgent to find a method which can effectively remove acetylenes in carbon four fraction and ensure low butadiene loss rate. SUMMARY

[0005] The present application aims to overcome the problems of low acetylene removal rate and high butadiene loss rate in the prior art when carbon four fraction is hydrogenated to remove acetylene, and provides a method for hydrogenation of carbon four fraction to remove acetylene.

[0006] To achieve the above objectives, the present invention provides a method for hydrogenating and removing alkynes from a C4 fraction. The method includes: contacting the C4 fraction with a catalyst under hydrogenation conditions, wherein the catalyst includes a support and a metal active component supported on the support, the metal active component including a first metal active component and an optional second metal active component, wherein the first metal active component is Cu, and the second metal active component is selected from at least one of Ni, Co, Pt, Pd, Rh, Ru, Mn, Co and Ag, and the support is carbon-modified alumina microspheres.

[0007] When using the method of this invention for the hydrotreating of C4 fractions to remove alkynes, a higher alkyne removal rate can be achieved while ensuring the lowest possible butadiene loss rate. The method of this invention can ensure stable operation of the C4 fraction hydrotreating to remove alkynes over a relatively long period (100 hours) without the need for repeated catalyst regeneration. Attached Figure Description

[0008] Figure 1 These are scanning electron microscope images of the alumina microspheres prepared in the preparation example.

[0009] Figure 2 This is a particle size distribution diagram of the alumina microspheres prepared in the preparation example. Detailed Implementation

[0010] 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.

[0011] In this invention, unless otherwise specified, the diameter of the alumina microspheres refers to the average diameter of the alumina microspheres.

[0012] In this invention, "ppm" and "ppb" represent volume concentration.

[0013] This invention provides a method for hydrogenating and removing alkynes from a C4 fraction. The method includes: contacting the C4 fraction with a catalyst under hydrogenation conditions. The catalyst includes 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 of Ni, Co, Pt, Pd, Rh, Ru, Mn, Co, and Ag. The support is carbon-modified alumina microspheres.

[0014] According to the present application, preferably, the contacting conditions include: temperature of 30-60℃, hydrogen pressure of 0.5-2MPa, liquid hourly space velocity of the carbon four fraction of 2-20h -1 , and molar ratio of hydrogen to acetylene in the carbon four fraction of 0.2-10. The temperature of the carbon four fraction contacting with the catalyst refers to the temperature at the inlet of the reactor.

[0015] According to the present application, preferably, the content of acetylene in the carbon four fraction is greater than or equal to 0.5% by volume, preferably 0.5-1.5% by volume.

[0016] According to the present application, preferably, the carbon four fraction contains at least one of butane, butene, butadiene and acetylene; more preferably, the acetylene is at least one of methylacetylene, ethylacetylene and vinylacetylene.

[0017] According to the present application, preferably, the content of butadiene in the carbon four fraction is greater than or equal to 40% by volume, preferably 40-60% by volume.

[0018] According to the present application, preferably, the carbon four fraction contains at least one of isobutane, n-butane, trans-2-butene, 1-butene, isobutene, cis-2-butene, 1,2-butadiene, 1,3-butadiene, methylacetylene, ethylacetylene and vinylacetylene.

[0019] According to the present application, preferably, the weight ratio of the first metal active component in terms of metal elements to the second metal active component in terms of metal elements is 50-300 (for example, 50, 100, 130, 150, 180, 200, 250, 280, 300).

[0020] According to the present application, preferably, the first metal active component is Cu, and the second metal active component is Pd.

[0021] According to the present application, preferably, the preparation method of the catalyst comprises: contacting alumina microspheres with a nitrogen-containing polymer solution, and then performing first calcination on the contacting product under inert atmosphere to obtain a carrier, and loading a metal active component on the carrier.

[0022] According to the present application, preferably, the particle diameter of the alumina microspheres is 200-800μm, and the coefficient of variation is 3-8%.

[0023] According to the present application, the source of the alumina microspheres is not particularly limited, as long as the particle diameter and the coefficient of variation of the alumina microspheres can meet the defined range. The alumina microspheres can be prepared according to the method described in the literature, for example, the method described in CN110203953B or CN110282642B. Preferably, the preparation method of the alumina microspheres comprises: taking an aluminum sol as a dispersed phase, taking an organic solvent as a continuous phase, forming droplets of the dispersed phase under the shearing action of the continuous phase, obtaining gel microspheres through solidification, and then obtaining alumina microspheres through drying and calcination.

[0024] According to the method for preparing alumina microspheres of the present application, preferably, the solid content of the aluminum sol is 5-8wt%.

[0025] According to the method for preparing alumina microspheres of the present application, preferably, the organic solvent used in the preparation of the alumina microspheres is a C1-C10 monovalent saturated alcohol, preferably octanol.

[0026] According to the method for preparing alumina microspheres of the present application, the drying temperature can be 100-120℃, and the drying time can be 3-15h.

[0027] According to the method for preparing alumina microspheres of the present application, the calcination temperature can be 550-1200℃, and the calcination time can be 4-10h.

[0028] According to the present application, preferably, the alumina microspheres are prepared in a microchannel reactor. The type of the microchannel reactor is not particularly limited, and the microchannel reactor is a single-channel reactor and / or a multi-channel reactor.

[0029] According to a further preferred embodiment of the present application, the multi-channel reactor is an eight-channel reactor. The structure of the eight-channel reactor is described below, which comprises a continuous phase distribution layer, a first droplet generation layer, a second droplet generation layer and a dispersed phase distribution layer, wherein the continuous phase distribution layer is composed of a petal-shaped resistance distribution channel, eight fluid outlets at the end of the petal-shaped resistance distribution channel, one continuous phase vertical inlet and four positioning holes, the fluid passing through each branch is called a level, a certain resistance is added before each fluid branch, and the width of the channel decreases with the increase of the circumferential radius of the starting end of each level; the first droplet generation layer is distributed with eight T-shaped channels, four positioning holes and eight through holes to meet the needs of the continuous phase self-distribution layer flowing to the generation layer, the second droplet generation layer is similar in structure to the first droplet generation layer, and eight droplet outlets are distributed at the end of the T-shaped channel main channel; the dispersed phase distribution layer is similar in structure to the continuous phase distribution layer, in addition to the eight dispersed phase outlets at the end of the petal-shaped resistance distribution channel, there is also one dispersed phase fluid inlet and eight product outlets.

[0030] According to the present application, preferably, the process for preparing alumina microspheres is exemplified by an eight-channel reactor. The alumina sol is used as the dispersed phase and the organic solvent is used as the continuous phase. The flow rate of the continuous phase is adjusted so that the continuous phase fills the continuous phase distribution layer and flows into the droplet generation layer, and then flows out of the outlet. The flow rate of the continuous phase is finally stabilized at 6-10 mL / min. The flow rate of the dispersed phase is adjusted to 1-4 mL / min so that the dispersed phase fills the dispersed phase distribution layer and flows into the droplet generation layer. The droplets are further generated under the shearing action of the continuous phase. The droplets are solidified in the 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.

[0031] According to the process for preparing catalysts of the present application, the amount of the nitrogen-containing polymer can be selected within a wide range. Preferably, the amount of the nitrogen-containing polymer solution is 0.1-1 g, more preferably 0.9-1 g, relative to 100 g of alumina microspheres.

[0032] According to the process for preparing catalysts of the present application, the conditions under which the alumina microspheres are contacted with the nitrogen-containing polymer solution can be selected within a wide range. Preferably, the alumina microspheres are contacted with the nitrogen-containing polymer solution at a temperature of 100-120°C for 4-10 h, preferably 8-10 h.

[0033] According to the process for preparing catalysts of the present application, the type of the nitrogen-containing polymer can be selected within a wide range. Preferably, the nitrogen-containing polymer in the nitrogen-containing polymer solution is a nitrogen-containing heterocyclic polymer, preferably at least one of polyvinylimidazole, polyvinylpyridine and polyvinylpyrrolidone, more preferably polyvinylimidazole.

[0034] According to the process for preparing catalysts of the present application, the concentration of the nitrogen-containing polymer in the nitrogen-containing polymer solution is not particularly limited. Preferably, the concentration of the nitrogen-containing polymer in the nitrogen-containing polymer solution is 0.1-1 wt%, preferably 0.9-1 wt%.

[0035] According to the process for preparing catalysts of the present application, preferably, the solvent in the nitrogen-containing polymer solution is an alcohol, preferably a C1-C4 saturated alcohol, more preferably methanol and / or ethanol.

[0036] According to the process for preparing catalysts of the present application, the conditions of the first calcination can be selected within a wide range. Preferably, the temperature of the first calcination is 400-800°C, preferably 400-450°C, and the time is 2-10 h, preferably 9-10 h.

[0037] According to the method for preparing the catalyst, the inert atmosphere used in the first calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

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

[0040] According to the method for preparing the catalyst, the inert atmosphere used in the first calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0041] According to the method for preparing the catalyst, the inert atmosphere used in the first calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0042] According to the method for preparing the catalyst, the inert atmosphere used in the first calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0043] According to the method for preparing the catalyst, the inert atmosphere used in the first calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0044] According to the method for preparing the catalyst, the inert atmosphere used in the first calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0045] According to the method for preparing the catalyst, the inert atmosphere used in the first calcination process is at least one of nitrogen atmosphere, argon atmosphere and helium atmosphere.

[0046] More preferably, the mass percentage of the copper salt solution in the impregnation solution containing the metal active component is 10-40wt%.

[0047] In the method for preparing the catalyst according to the present application, the metal active component can also be loaded on the carrier by means of twice calcination, thus, preferably, the method for loading the metal active component on the carrier is: using a first part of the solution containing the metal active component to contact with the carrier, and then performing primary calcination under inert atmosphere; using a second part of the solution containing the metal active component to contact with the product of the primary calcination, and then performing secondary calcination under inert atmosphere.

[0048] In the method for preparing the catalyst according to the present application, preferably, the metal active component in the first part of the solution containing the metal active component is Cu.

[0049] In the method for preparing the catalyst according to the present application, preferably, the metal active component in the second part of the solution containing the metal active component is Pd.

[0050] Preferably, the mass percentage content of the copper salt solution in the first part of the solution containing the metal active component is 10-40wt%.

[0051] Preferably, the mass percentage content of the palladium salt solution in the second part of the solution containing the metal active component is 0.01-0.3wt%.

[0052] In the method for preparing the catalyst according to the present application, preferably, the method for using the first part of the solution containing the metal active component to contact with the carrier is impregnation and / or spraying.

[0053] In the method for preparing the catalyst according to the present application, preferably, the conditions for impregnating the carrier with the first part of the solution containing the metal active component include impregnating at 15-40℃ for 0.2-1h; more preferably, the carrier is impregnated with the first part of the solution containing the metal active component, and then the product after impregnation is dried at 100-140℃ for 10-15h, and then primary calcination is performed under inert atmosphere.

[0054] In the method for preparing the catalyst according to the present application, preferably, the conditions for spraying the carrier with the first part of the solution containing the metal active component include spraying at 15-40℃ for 0.2-0.5h; more preferably, the carrier is sprayed with the first part of the solution containing the metal active component, and then the product after spraying is placed in air for 1-3h, and then dried at 100-140℃ for 10-15h, and then primary calcination is performed under inert atmosphere.

[0055] In the method for preparing the catalyst according to the present application, preferably, the conditions for the primary calcination include: temperature is 400-800℃, and time is 2-10h.

[0056] In the method for preparing a catalyst according to the present application, preferably, the way of contacting the solution of the second part of the metal-containing active component with the primary calcination product is impregnation and / or spraying.

[0057] In the method for preparing a catalyst according to the present application, preferably, the conditions of impregnating the primary calcination product with the solution of the second part of the metal-containing active component include impregnation at 15-40℃ for 0.2-1h; more preferably, the primary calcination product is sprayed with the solution of the second part of the metal-containing active component, the product after spraying is placed in air for 1-3h, dried at 100-140℃ for 10-15h, and then subjected to secondary calcination in an inert atmosphere.

[0058] In the method for preparing a catalyst according to the present application, preferably, the conditions of spraying the primary calcination product with the solution of the second part of the metal-containing active component include spraying at 15-40℃ for 0.2-0.5h; more preferably, the primary calcination product is sprayed with the solution of the second part of the metal-containing active component, the product after spraying is placed in air for 1-3h, dried at 100-140℃ for 10-15h, and then subjected to secondary calcination in an inert atmosphere.

[0059] In the method for preparing a catalyst according to the present application, preferably, the conditions of the secondary calcination include a temperature of 400-800℃ and a time of 2-10h.

[0060] In the method for preparing a catalyst according to the present application, preferably, the inert atmosphere used in the primary calcination and the secondary calcination is at least one of a nitrogen atmosphere, an argon atmosphere and a helium atmosphere.

[0061] The present application will be described in detail below by way of examples. In the following examples,

[0062] The room temperature is about "25℃".

[0063] The diameter of the alumina microspheres is tested by a scanning electron microscope.

[0064] Method for testing the coefficient of variation: the number of alumina microspheres in a unit area is measured by a scanning electron microscope, and the diameter of each alumina microsphere is measured, and then the coefficient of variation is calculated according to the formula.

[0065] The coefficient of variation is calculated according to the following formula:

[0066]

[0067] CV: coefficient of variation, n: number of alumina microsphere particles, X i : diameter of a single alumina microsphere particle, average value of the diameter of all alumina microsphere particles.

[0068]

[0069]

[0070] Preparation Example

[0071] The dispersed phase was selected as an aluminum sol with solid content of 7.5wt%, the continuous phase and the liquid in the oil column were selected as octanol, an organic solvent. First, the flow rate of the continuous phase was adjusted so that the continuous phase filled the continuous phase distribution layer 1 and flowed into the droplet generation layer, and then flowed out from the outlet. The flow rate of the continuous phase was finally stabilized at 6-10mL / min. Then, the flow rate of the dispersed phase was adjusted to 1-4mL / min so that the dispersed phase filled the dispersed phase distribution layer 4 and flowed into the droplet generation layer, and further generated droplets under the shearing action of the continuous phase. The droplets were solidified in the oil column to obtain gel microspheres. After drying at 120℃ for 12h and calcination at 600℃ for 4h, alumina microspheres with a diameter of 345μm and a coefficient of variation of 7.2% were obtained.

[0072] The scanning electron microscope image of the alumina microspheres is shown in Figure 1 The alumina microspheres were in the range of 300-400μm in diameter and were uniform spherical particles.

[0073] The particle size distribution diagram of the alumina microspheres is shown in Figure 2 It can be seen from Figure 2 that the particle size distribution range of the alumina microspheres is very narrow.

[0074] Example 1

[0075] (1) 100g of the alumina microspheres obtained in the preparation example were immersed in an ethanol solution of polyvinylimidazole with a concentration of 1wt% (wherein the amount of polyvinylimidazole was 1g), and then transferred to an autoclave for reaction at 100℃ for 10h. After cooling and filtration, the product was dried at 80℃ for 4h, and then placed in a nitrogen atmosphere and calcined at 400℃ for 10h to obtain a carrier (carbon-doped alumina microspheres).

[0076] (2) 20g of the carrier was placed in a 16wt% aqueous copper nitrate solution (wherein the amount of copper nitrate was 3.52g in terms of metal elements), and after immersion at room temperature for 20min, the carrier was taken out and drained. The product was dried at 120℃ for 12h and calcined at 400℃ in a nitrogen atmosphere for 3h to obtain a catalyst.

[0077] The XRF characterization showed that the loading amount of copper in the catalyst was 14.9wt%.

[0078] Example 2

[0079] Step (1) was the same as in Example 1.

[0080] (2) 20 g of the support was put into 20 wt% copper nitrate aqueous solution (copper nitrate was 4.4 g in terms of metal element) and soaked at room temperature for 20 min, then the support was taken out and drained, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h in nitrogen atmosphere to obtain the catalyst.

[0081] The loading of copper in the catalyst was 16.8 wt% by XRF characterization.

[0082] Example 3

[0083] Step (1) was the same as that in Example 1.

[0084] (2) 20 g of the support was put into 20 wt% copper nitrate aqueous solution (copper nitrate was 4.4 g in terms of metal element) and soaked at room temperature for 20 min, then the support was taken out and drained, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h in nitrogen atmosphere to obtain the catalyst.

[0085] (3) The primary calcination product obtained in step (2) was put into a mixed solution composed of 0.1 wt% palladium nitrate aqueous solution (palladium nitrate was 0.016 g in terms of metal element), soaked at room temperature for 20 min, then the support was taken out and drained, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h in nitrogen atmosphere to obtain the catalyst.

[0086] The loading of copper in the catalyst was 14.8 wt% and the loading of palladium was 0.07 wt% by XRF characterization.

[0087] Example 4

[0088] Step (1) was the same as that in Example 1.

[0089] (2) 20 g of the support was put into 20 wt% copper nitrate aqueous solution (copper nitrate was 4.4 g in terms of metal element) and soaked at room temperature for 20 min, then the support was taken out and drained, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h in nitrogen atmosphere to obtain the catalyst.

[0090] (3) The primary calcination product obtained in step (2) was put into a mixed solution composed of 0.1 wt% palladium nitrate aqueous solution (palladium nitrate was 0.016 g in terms of metal element), soaked at room temperature for 20 min, then the support was taken out and drained, dried at 120 °C for 12 h, and calcined at 400 °C for 3 h in nitrogen atmosphere to obtain the catalyst.

[0091] The loading of copper in the catalyst was 14.8 wt% and the loading of palladium was 0.07 wt% by XRF characterization.

[0092] Example 5

[0093] Step (1) is the same as Example 1.

[0094] (2) 20 g of the support was sprayed with 16 wt% aqueous copper nitrate solution (copper nitrate was used in an amount of 3.52 g in terms of metal elements) at room temperature for 0.2 h, left 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 a primary calcination product.

[0095] (3) The primary calcination product obtained in step (2) was sprayed with 0.3 wt% aqueous palladium nitrate solution (palladium nitrate was used in an amount of 0.048 g in terms of metal elements) at room temperature for 0.2 h, left 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.

[0096] The catalyst was characterized by XRF, and the loading of copper in the catalyst was 14.9 wt%, and the loading of palladium was 0.2 wt%.

[0097] Comparative Example 1

[0098] The catalyst was prepared according to the method of Example 3, except that the alumina microspheres were directly used as the support.

[0099] The catalyst was characterized by XRF, and the loading of copper in the catalyst was 14.8 wt%, and the loading of palladium was 0.07 wt%.

[0100] Comparative Example 2

[0101] The catalyst was prepared according to the method of Example 4, except that the alumina microspheres were directly used as the support.

[0102] The catalyst was characterized by XRF, and the loading of copper in the catalyst was 18 wt%, and the loading of palladium was 0.13 wt%.

[0103] Comparative Example 3

[0104] The catalyst was prepared according to the method of Example 5, except that the alumina microspheres were directly used as the support.

[0105] The catalyst was characterized by XRF, and the loading of copper in the catalyst was 14.9 wt%, and the loading of palladium was 0.2 wt%.

[0106] Test Example

[0107] The catalyst evaluation was carried out in a reactor, which was a two-stage fixed bed reactor (Stage I and Stage II). Each stage was loaded with 20 mL of catalyst, and after nitrogen conversion, the carbon four fraction was mixed with hydrogen and fed into the reactor. The metered carbon four fraction feedstock was mixed with metered hydrogen, and sequentially fed into Stage I and Stage II reactors from the lower part of the reactor. The reaction product flowed out from the top of the reactor and entered the product storage tank. The catalyst was replaced with nitrogen before the reaction, and then reduced with hydrogen at 150°C for 2 h. The composition of the carbon four fraction is shown in Table 1. The reaction time for the evaluation was 100 h, and the reaction conditions and test results are shown in Table 2. The content of each component in the carbon four fraction and hydrogenated product was determined by gas chromatography.

[0108] Table 1

[0109] Component Content (vol%) Component Content (vol%) Isobutane 2.35 1,2-Butadiene 0.17 n-Butane 4.73 1,3-Butadiene 48.56 Trans-2-Butene 4.49 Methylacetylene 0.08 1-Butene 13.9 Ethylacetylene 0.73 Isobutene 21.31 Vinylacetylene 0.14 Cis-2-Butene 3.36

[0110] Table 2

[0111]

[0112] As can be seen from the results in Table 2, compared with the comparative examples, the catalysts in Examples 1-5 can effectively remove acetylenes in the carbon four fraction while ensuring that the loss of butadiene is less than 3%. In particular, the method of Examples 3-5 of the present application can achieve even better results.

[0113] The above describes preferred embodiments of the present application, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be considered as disclosed by the present application and fall within the protection scope of the present application.

Claims

1. A method for hydrogenating and removing alkynes from a C4 fraction, characterized in that, The method includes: contacting a C4 fraction 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, and the second metal active component being selected from at least one of Ni, Co, Pt, Pd, Rh, Ru, Mn, Co, and Ag, wherein the support is carbon-modified alumina microspheres; 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 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 alkyne content in the C4 fraction is 0.5-1.5% by volume. The butadiene content in the C4 fraction is 40-60% by volume. The contact conditions between the C4 fraction and the catalyst include: a temperature of 30°C-60°C, a hydrogen pressure of 0.5-2 MPa, and a liquid hourly space velocity (LHSV) of 2-20 h⁻¹ for the C4 fraction. -1 The molar ratio of hydrogen to alkynes in the C4 fraction is 0.2-10.

2. The method according to claim 1, wherein, The C4 fraction contains at least one of butane, butene, butadiene, and alkynes.

3. The method according to claim 1, wherein, 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 50-300. And / or, the first metal active component is Cu, and the second metal active component is Pd.

4. 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%.

5. 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.

6. 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.

7. The method according to claim 1 or 6, wherein, The nitrogen-containing polymer in the nitrogen-containing polymer solution is polyvinylimidazole.

8. The method according to claim 1 or 6, wherein, The solvent in the nitrogen-containing polymer solution is a C1-C4 saturated alcohol.

9. The method according to claim 1 or 6, wherein, The solvent in the nitrogen-containing polymer solution is methanol and / or ethanol.

10. 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.

11. 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.

12. The method according to claim 1 or 11, wherein, The amount of the metal active component, calculated as metal element, is 3.5-5g relative to 20g of carrier.

13. 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.

14. The method according to claim 13, 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.

15. The method according to claim 13, 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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