C4 fraction selective hydroisomerization catalyst as well as preparation method and application thereof

Abstract

The present invention provides a C4 fraction selective hydroisomerization catalyst, which comprises a carrier and an active component loaded on the carrier, and the carrier is a metal composite oxide modified by an organic cation quaternary ammonium salt and a silane reagent; the metal composite oxide contains a metal element I, and the metal element I comprises aluminum and titanium; the active component contains a metal element II, the metal element II comprises a main active component Cu and an optional auxiliary active component, and the auxiliary active component comprises Ni, Ru and alkali metal. According to the selective hydrogenation catalyst provided by the invention, the carrier is modified, so that the dispersion of the active components on the surface of the carrier can be remarkably improved, and the active components are controlled to exist in a nanocluster form on the surface of the carrier, so that the low-temperature activity of the catalyst prepared from the carrier precursor is remarkably improved. The invention also provides a preparation method and application of the C4 fraction selective hydrogenation isomerization catalyst, and a method for removing butadiene and preparing 1-butene through C4 fraction selective hydrogenation.

Description

Technical Field

[0001] This invention relates to the field of selective hydrogenation technology for C4 fractions, and particularly to a selective hydrogenation isomer catalyst for C4 fractions, its preparation method, and its application. Background Technology

[0002] C4 fraction refers to a mixture of various alkanes, alkenes, dienes, and alkynes containing four carbon atoms. It mainly originates from refinery gas produced during petroleum refining and byproducts of ethylene production from petroleum hydrocarbon cracking. Cracked C4 fractions contain saturated and unsaturated hydrocarbons such as n-butane, isobutane, 1-butene, trans-2-butene, cis-2-butene, isobutene, 1,2-butadiene, 1,3-butadiene, methylacetylene, ethylacetylene, and vinylacetylene. Industrially, it is mainly used to produce 1,3-butadiene, isobutene, and 1-butene.

[0003] 1-Butene is an important chemical raw material, mainly used as a monomer for copolymerizing linear low-density polyethylene (LLDPE) and producing poly-1-butene plastics. It can also be used as a main raw material to produce high-value-added chemical products such as sec-butanol and methyl ethyl ketone. 1-Butene oligomerization can produce C8 and C12 α-olefins, which are excellent raw materials for preparing surfactants and have wide applications in petrochemical, fine chemical, pharmaceutical, and pesticide fields.

[0004] In methods for producing butene from cracked C4 hydrocarbons, one approach involves selectively hydrogenating the cracked C4 hydrocarbons directly, hydrogenating 1,2-butadiene, 1,3-butadiene, methylacetylene, ethylacetylene, and vinylacetylene to generate mono-olefins such as 1-butene, trans-2-butene, and cis-2-butene, while avoiding further hydrogenation of these mono-olefins to form alkanes. Another method involves first separating 1,3-butadiene from the cracked C4 hydrocarbons. The remaining byproduct, mainly containing C4 alkanes and C4 mono-olefins, is called the C4 raffinate. This raffinate often contains approximately 1.0 wt% 1,3-butadiene, which needs to be removed by selective hydrogenation. Currently, the catalysts used in industrial production for the selective hydrogenation of C4 hydrocarbons to butene are Pd / Al2O3 catalysts and Pd-Ag / Al2O3 bimetallic catalysts; non-precious metal catalysts are rarely used.

[0005] Noble metal catalysts generally employ palladium catalysts supported on a carrier (usually alumina), with the addition of other co-catalyst components such as gold, silver, chromium, copper, iron, rhodium, lithium, potassium, and even lead or zinc. Noble metal catalysts exhibit good low-temperature activity and mild reaction conditions, but their drawbacks include easy loss of active components, high cost, difficulty in regeneration, and slightly poor hydrogenation selectivity. Non-noble metal catalysts require higher temperatures and harsher hydrogenation conditions, but their preparation is simple, they are easy to regenerate repeatedly, and their cost is relatively low, thus still possessing certain research and development value. In these hydrogenation reactions, semi-hydrogenated free radicals adsorbed on the catalyst react with adjacent dienes to form a viscous polymer (commonly known as green oil), mainly composed of compounds with more than six carbon atoms. Because it covers the catalyst surface, it blocks the micropores, reducing catalyst activity and affecting catalyst lifespan. Especially for conjugated dienes (such as 1,3-butadiene), their polymerization reaction is more likely to occur, causing the catalyst to deactivate quickly, thus requiring frequent regeneration for reuse.

[0006] In the application research of selective hydrogenation of C4 alkynes, it has been recognized that nickel-based selective hydrogenation catalysts are safer and more efficient for feedstocks with high butadiene content. However, the activity and selectivity of nickel-based selective hydrogenation catalysts are somewhat inferior to those of noble metal palladium-based catalysts, limiting their application. Therefore, for non-noble metal catalysts used in the selective hydrogenation of alkynes, it is necessary to further improve the activity and selectivity of these catalysts, research countermeasures to address the green oil problem during catalyst use, and extend catalyst life. Using non-noble metal hydrogenation catalysts for the selective hydrogenation of alkynes can improve the catalyst's resistance to impurity poisoning and its stability, which has economic value. Summary of the Invention

[0007] In order to overcome at least one of the above-mentioned problems in the prior art, one of the objectives of the present invention is to provide a non-precious metal C4 fraction selective hydroisomerization catalyst with high low-temperature activity, high selectivity and high stability, which can save more than 70% of the catalyst production cost, and the catalyst has good resistance to impurity poisoning and good raw material adaptability.

[0008] The second objective of this invention is to provide a selective hydroisomerization catalyst for C4 alkynes prepared by the above-mentioned method.

[0009] The third objective of this invention is to provide an application of the above-mentioned selective hydroisomerization catalyst for C4 fraction alkynes.

[0010] The fourth objective of this invention is to provide a method for selectively hydrogenating alkynes in C4 fractions to remove alkynes and increase butadiene production.

[0011] Therefore, in a first aspect, the present invention provides a C4 fraction selective hydroisomerization catalyst, comprising a support and an active component supported on the support.

[0012] The carrier is a metal composite oxide modified with organic cationic quaternary ammonium salt and silane reagents; the metal composite oxide contains metal element I, which includes aluminum and titanium;

[0013] The active component contains metal element II, which includes the main active component Cu and optional auxiliary active components, including Ni, Ru and alkali metals.

[0014] The selective hydrogenation catalyst provided by this invention has a support modified with organic cationic quaternary ammonium salt and silane reagents, which solves the problem of low crushing strength of metal composite oxides caused by the introduction of Ti. The support has higher crushing strength, which can effectively avoid the pulverization problem of the catalyst during long-term operation. It can also be produced by extrusion, and the irregular surface can be used to increase the contact area between the outer surface of the catalyst and the physical environment, thereby improving the activity of the catalyst.

[0015] The selective hydrogenation catalyst provided by this invention has a support modified with organic cationic quaternary ammonium salt and silane reagents, which can significantly improve the dispersion of active components on the support surface and control the active components to be distributed on the support in the form of nanoclusters with a particle size of less than 5 nm, thereby significantly improving the low-temperature activity, selectivity and stability of the catalyst prepared from the support precursor.

[0016] As a specific embodiment of the present invention, the organic cationic quaternary ammonium salt includes a hydrocarbon-based quaternary ammonium salt.

[0017] As a specific embodiment of the present invention, the general formula of the hydrocarbon-based quaternary ammonium salt is R4N. + X - , where X - Selected from halide ions and acid radical ions, preferably, the halide ions include F. - Cl - ,Br - and I - The acid radical ions include nitrate ions and carboxylate ions, with the general formula R4N. + X - Each R may be the same or different, and each is independently selected from alkyl, cycloalkyl, aryl, aralkyl and alkylaryl. At least one R is selected from alkyl with more than 6 Cs, preferably from alkyl with 6 to 20 Cs, and the remaining Rs are preferably selected from alkyl with 1 to 4 Cs or aralkyl with 7 to 11 Cs.

[0018] As a specific embodiment of the present invention, the general formula R4N + X -The Rs may be the same or different, at least 1 to 2 Rs are selected from C6 or higher alkyl groups, preferably from C6 to 20 alkyl groups, and the remaining Rs are preferably selected from C1 to C4 alkyl groups or C7 to C11 aryl alkyl groups.

[0019] As a specific embodiment of the present invention, the organic cationic quaternary ammonium salt includes at least one of di(octadecyl)dimethyl quaternary ammonium salt, hexadecyltrimethyl quaternary ammonium salt, and C12-18 alkyldimethylbenzyl quaternary ammonium salt.

[0020] As a specific embodiment of the present invention, the organic cationic quaternary ammonium salt is selected from at least one of bis(octadecyl)dimethylammonium chloride, hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, dodecyldimethylbenzylammonium chloride, tetradecyldimethylbenzylammonium chloride, hexadecyldimethylbenzylammonium chloride and octadecyldimethylbenzylammonium chloride.

[0021] As a specific embodiment of the present invention, the general formula of the silane reagent is SiR. 1 x (OR 2 ) y Where x and y are each independently selected from integers from 1 to 3, x + y = 4, R 1 Selected from hydrogen, C1-C6 alkyl and C2-C6 alkenyl, R 2 Selected from C1 to C6 alkyl groups.

[0022] As a specific embodiment of the present invention, the silane reagent includes at least one selected from triethoxysilane, trimethoxysilane, methyltriethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane. The methoxy and ethoxy functional groups in the above-mentioned silane reagents bind to the hydroxyl groups on the support surface, improving the dispersibility of metals and their oxides on the surface and reducing particle size.

[0023] In a specific embodiment of the present invention, the amount of the organic cationic quaternary ammonium salt is 1%-50% of the mass of the metal composite oxide. According to the present invention, controlling the above ratio can increase the hydroxyl groups on the carrier surface and improve the affinity between the carrier surface and the additives.

[0024] In a specific embodiment of the present invention, the amount of the organic cationic quaternary ammonium salt is 30%-50% of the mass of the metal composite oxide. According to the present invention, controlling the above ratio can further increase the hydroxyl groups on the carrier surface and improve the affinity between the carrier surface and the additives.

[0025] In a specific embodiment of the present invention, the amount of the organic cationic quaternary ammonium salt is 35%-50% of the mass of the metal composite oxide. According to the present invention, controlling the above ratio can further increase the hydroxyl groups on the carrier surface and improve the affinity between the carrier surface and the additives.

[0026] In a specific embodiment of the present invention, the amount of the silane reagent is 0.5%-30% of the mass of the metal composite oxide. According to the present invention, controlling the above ratio can increase the hydrophobicity of the support surface and improve the dispersion of the catalyst active component on the support surface.

[0027] In a specific embodiment of the present invention, the amount of the silane reagent is 0.5%-15% of the mass of the metal composite oxide. According to the present invention, controlling the above ratio can further improve the hydrophobicity of the support surface and increase the dispersion of the catalyst active component on the support surface.

[0028] In a specific embodiment of the present invention, the amount of the silane reagent is 0.5%-10% of the mass of the metal composite oxide. According to the present invention, controlling the above ratio can further improve the hydrophobicity of the support surface and increase the dispersion of the catalyst active component on the support surface.

[0029] As a specific embodiment of the present invention, the alkali metal is selected from at least one of lithium, sodium, potassium, and rubidium.

[0030] As a specific embodiment of the present invention, the metal composite oxide is an Al2O3-TiO2 composite oxide.

[0031] As a specific embodiment of the present invention, based on the Al2O3-TiO2 composite oxide, the content of Ti in the Al2O3-TiO2 composite oxide, calculated as TiO2, is 5-30 wt%, and the content of Al, calculated as Al2O3, is 70 wt%-95 wt%. According to the present invention, controlling Al2O3 and TiO2 in the above-mentioned ratio can improve crushing strength, increase specific surface area and pore volume, improve the electronic properties of the catalyst surface, and enhance catalyst activity.

[0032] As a specific embodiment of the present invention, based on the Al2O3-TiO2 composite oxide, the content of Ti in the Al2O3-TiO2 composite oxide, calculated as TiO2, is 8wt% to 25wt%; and the content of Al, calculated as Al2O3, is 75wt% to 92wt%. According to the present invention, controlling Al2O3 and TiO2 in the above-mentioned ratio can further improve the crushing strength, the larger specific surface area and pore volume, improve the electronic properties of the catalyst surface, and enhance the catalyst activity.

[0033] In a specific embodiment of the present invention, the carrier is a SiO2-TiO2-Al2O3 composite oxide.

[0034] As a specific embodiment of the present invention, based on the carrier, the content of Ti in the carrier, calculated as TiO2, is 5wt% to 25wt%, the content of Al, calculated as Al2O3, is 65wt% to 90wt%, preferably 80wt% to 90wt%, and the content of Si, calculated as SiO2, is 0.5wt% to 15wt%.

[0035] As a specific embodiment of the present invention, based on 100 parts by mass of catalyst, the content of active component Cu in the catalyst is 5 to 25 parts, calculated as CuO; the content of active component Ru is 0 to 5 parts, preferably 0.1 to 5 parts, calculated as its oxide; the content of active component Ni is 0 to 5 parts, preferably 0.1 to 5 parts, calculated as its oxide; the content of alkali metal is 0 to 1 part, preferably 0.1 to 0.5 parts, calculated as its oxide; and the content of support is 70 to 95 parts.

[0036] In a specific embodiment of the present invention, the active component is distributed on the carrier in the form of nanoclusters, wherein the particle size of the nanoclusters is less than 5 nm.

[0037] In a specific embodiment of the present invention, the specific surface area of ​​the carrier is 30–150 μm. 2 / g, preferably 50-90m 2 / g.

[0038] As a specific embodiment of the present invention, the pore volume of the carrier is 0.2 to 0.8 mL / g, preferably 0.3 to 0.5 mL / g.

[0039] In a specific embodiment of the present invention, the main active component and the co-active component in the catalyst each exist independently in the form of their elemental form or oxide.

[0040] As a specific embodiment of the present invention, the preparation of the carrier includes the following steps: the metal composite oxide is subjected to a first treatment with an organic cationic quaternary ammonium salt solution, and the treated metal composite oxide is subjected to a second treatment with a silane reagent to obtain the carrier.

[0041] In a specific embodiment of the present invention, the first treatment includes a first impregnation and a first drying performed sequentially. According to the present invention, using an organic cationic quaternary ammonium salt solution to impregnate the metal composite oxide can effectively control the possibility of metal ions participating in the oxidation reaction.

[0042] As a specific embodiment of the present invention, the second treatment includes adding a solution of silane reagent dropwise onto the metal composite oxide that has undergone the first treatment, followed by stirring, second drying, and first calcination, preferably with a stirring time of 1 min to 60 min.

[0043] As a specific embodiment of the present invention, the concentration of the organic cation quaternary ammonium salt solution is 0.1 wt% to 10 wt%, preferably 0.2 to 10 wt%, and more preferably 1 to 5 wt%.

[0044] As a specific embodiment of the present invention, the solvent of the solution of the organic cationic quaternary ammonium salt includes at least one of water, methanol, ethanol, benzene, toluene, isopropanol, acetone, sulfuric acid, hydrochloric acid, nitric acid, sodium hydroxide, and potassium hydroxide.

[0045] As a specific embodiment of the present invention, the solution of the organic cation quaternary ammonium salt is an alkaline solution of the organic cation quaternary ammonium salt, wherein the alkaline solution is selected from at least one of ammonia, sodium hydroxide, and potassium hydroxide, and preferably, the concentration of the alkaline solution is 0.2 to 0.4 mol / L.

[0046] As a specific embodiment of the present invention, the solution of the silane reagent is an aqueous solution of the silane reagent with a concentration of 0.1-10 wt%, preferably 1-10 wt%.

[0047] As a specific embodiment of the present invention, the conditions for the first impregnation include: impregnation temperature of 10°C to 50°C, and impregnation time of 1 hour to 12 hours, preferably 1 hour to 8 hours.

[0048] As a specific embodiment of the present invention, the conditions for the first drying and the second drying each independently include: drying temperature of 60℃~150℃, preferably 60℃~110℃, and drying time of 4h~12h.

[0049] As a specific embodiment of the present invention, the conditions for the first roasting include: a roasting temperature of 300-1100°C, preferably 500-900°C, and a roasting time of 4-12 hours.

[0050] Therefore, in a second aspect, the present invention provides a method for preparing the above-mentioned C4 fraction selective hydroisomerization catalyst, comprising the following steps: second impregnating a support with a copper salt solution, optionally a nickel salt solution, optionally a ruthenium salt solution, and optionally an alkali metal salt solution; and third drying and second calcining the impregnated support to obtain the catalyst.

[0051] As a specific embodiment of the present invention, the copper salt includes at least one of copper sulfate, nitrate, soluble carboxylate, hypophosphite and halide, preferably at least one of copper sulfate, copper nitrate, copper chloride and copper acetate.

[0052] As a specific embodiment of the present invention, the nickel salt includes at least one of nickel nitrate, soluble carboxylate and halide, preferably at least one of nickel nitrate, hydrochloride, oxalate and acetate.

[0053] As a specific embodiment of the present invention, the ruthenium salt includes at least one of ruthenium nitrate, soluble carboxylate and halide, preferably at least one of ruthenium nitrate, hydrochloride, oxalate and acetate.

[0054] As a specific embodiment of the present invention, the alkali metal salt is selected from at least one of lithium salt, sodium salt, potassium salt, and rubidium salt.

[0055] As a specific embodiment of the present invention, the solvents in the copper salt solution, nickel salt solution, ruthenium salt solution and alkali metal salt solution are each independently at least one selected from water, methanol, ethanol, benzene, toluene and chloroethane.

[0056] In a specific embodiment of the present invention, the concentration of the copper salt solution is 0.1 to 0.6 mol / L.

[0057] In a specific embodiment of the present invention, the concentration of the nickel salt solution is 0.1 to 0.3 mol / L.

[0058] As a specific embodiment of the present invention, the concentration of the ruthenium salt solution is 0.01 to 0.1 mol / L.

[0059] As a specific embodiment of the present invention, the concentration of the alkali metal salt solution is 0.1 to 0.3 mol / L.

[0060] As a specific embodiment of the present invention, the conditions for the second impregnation include: temperature of 20°C to 70°C, preferably 20°C to 40°C, and time of 1 hour to 12 hours, preferably 1 hour to 4 hours.

[0061] As a specific embodiment of the present invention, the conditions for the third drying include: a temperature of 60-150°C, preferably 100-150°C, and a time of 1-8 hours, preferably 4-8 hours.

[0062] As a specific embodiment of the present invention, the conditions for the second calcination include: a temperature of 300-600°C, preferably 400-500°C, and a time of 4-12 hours.

[0063] Therefore, in a third aspect, the present invention provides the application of the above-described C4 fraction selective hydroisomerization catalyst or the C4 fraction selective hydroisomerization catalyst prepared by the above-described preparation method in the selective hydrogenation of C4 fractions to remove butadiene and to produce 1-butene.

[0064] As a specific embodiment of the present invention, the conditions for selecting hydrogenation include: reaction temperature of 20℃~40℃, molar ratio of hydrogen to alkyne of 1~2.5:1, pressure of 0.5MPa~0.8MPa, and recycle ratio of 10~30:1.

[0065] In a specific embodiment of the present invention, the catalyst is divided into upper and lower layers of composite loading, and the weight ratio between the upper catalyst layer and the lower catalyst layer is 1 to 3:1.

[0066] Therefore, in a fourth aspect, the present invention provides a method for selective hydrogenation of C4 fractions to remove butadiene and to produce 1-butene, using the above-mentioned C4 fraction selective hydrogenation catalyst or the C4 fraction selective hydrogenation catalyst prepared by the above-mentioned preparation method as the catalyst.

[0067] As a specific embodiment of the present invention, the conditions for selecting hydrogenation include: reaction temperature of 20℃~40℃, molar ratio of hydrogen to alkyne of 1~2.5:1, pressure of 0.5MPa~0.8MPa, and recycle ratio of 10~30:1.

[0068] In a specific embodiment of the present invention, the catalyst is divided into upper and lower layers of composite loading, and the weight ratio between the upper catalyst layer and the lower catalyst layer is 1 to 3:1.

[0069] The beneficial effects of this invention are as follows:

[0070] (1) The selective hydrogenation catalyst provided by the present invention has a support treated with organic cationic quaternary ammonium salt and silane reagent, which can significantly improve the dispersion of active components on the support surface and control the active components to be distributed on the support in the form of nano clusters. The nano clusters reach below 5 nm, thereby significantly improving the low-temperature activity, selectivity and stability of the catalyst containing the support.

[0071] (2) The selective hydrogenation catalyst provided by the present invention has its support treated with organic cationic quaternary ammonium salt and silane reagents, which helps to overcome the disadvantage of low crushing strength caused by the introduction of TiO2 into the support. The crushing strength of the prepared catalyst is improved compared with the catalyst prepared by unmodified composite oxide. The higher crushing strength can effectively avoid the pulverization problem of the catalyst during long-term operation. It can also be produced by extrusion, and the shaped surface can be used to increase the contact area between the outer surface of the catalyst and the physical environment, thereby improving the activity of the catalyst.

[0072] (3) The catalyst of the present invention has high low-temperature reaction activity and selectivity, its preparation process is simple, the reaction conditions are mild, the production cost is low, and it can operate stably for a long time in production, which has industrial application value.

[0073] (4) The C4 fraction selective hydroisomerization catalyst provided by the present invention has the advantages of high selectivity, high low temperature activity, and stable hydrogenation activity, and can be used for a long period of time. Attached Figure Description

[0074] Figure 1 This is a TEM characterization image of catalyst A. Detailed Implementation

[0075] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0076] The TiO2 content was determined using a spectrophotometer, and the parameter detection method was the standard curve method. The principle utilized was that in sulfuric acid solution, Ti... 4+ It forms a yellow complex with hydrogen peroxide. Titanium dioxide reacts with hot sulfuric acid to form titanyl sulfate, which then reacts with hydrogen peroxide to form a stable, orange-yellow [TiO(H₂O₂)]₂. 2- The results were measured at 430 nm using a spectrophotometer.

[0077] The specific surface area, pore volume, and most probable pore size of the support were determined using an ASAP 2020 adsorption analyzer (N2 adsorption-desorption method) from Micron Instruments, Inc., USA. The parameters were measured using the static volumetric method. Before testing, the catalyst samples were degassed at 623 K for 4 h and then adsorbed with nitrogen at liquid nitrogen temperature. Sample data were processed using AMSM software, and the specific surface area was obtained using the Brunauer-Emmet-Teller (BET) method. The average pore size was obtained from the nitrogen adsorption isotherm using the Barrett-Joyner-Halenda (BJH) method, and the pore volume was obtained using the P / Po single-point desorption curve.

[0078] The contents of Cu, Ni, Ru, and alkali metals in the catalyst were determined using an ICP atomic emission spectrometer, based on the JYT015 General Rules for Inductively Coupled Plasma Atomic Emission Spectrometry. A PerkinElmer (PE) Optima 8300 full-spectrum direct-reading ICP spectrometer with an echelle grating, solid-state detector, and dual-path dual-solid-state detectors in the ultraviolet and visible regions was used, employing planar plasma technology to ensure minimal argon consumption.

[0079] Catalyst characterization methods

[0080] The catalyst was observed using a Jem-3010 high-resolution transmission electron microscope with an accelerating voltage of 200 kV for HR-TEM characterization. Before testing, the catalyst sample was thoroughly ground into powder. A small amount of the sample was added to anhydrous ethanol and placed in an ultrasonic cleaner (model PS-10, Shenzhen Jiekang Ultrasonic Cleaning Machine Co., Ltd.) for ultrasonic separation for 15–20 min. Finally, the suspension was continuously added dropwise onto the microgrid using a dropper and allowed to air dry.

[0081] Preparation Example 1

[0082] The selected material is a TiO2-Al2O3 composite oxide produced by Yantai Heng Hui Chemical Co., Ltd., containing 15wt% TiO2 and 85wt% Al2O3, with a specific surface area of ​​60m². 2 / g, pore volume 0.55mL / g.

[0083] 100g of TiO2-Al2O3 composite oxide was impregnated with 1L of a 5wt% dimethyl dioctadecyl ammonium chloride methanol solution for 2h, and then dried at 70℃ for 10h. 100g of a 2wt% vinyltrimethoxysilane aqueous solution was added dropwise to the dried composite oxide. After the addition was completed, the resulting mixture was stirred uniformly for 10 minutes. The mixture was then dried at 70℃ for 10h and calcined at 850℃ for 4h to obtain the modified composite oxide support A'.

[0084] The support A' contains 14.9 wt% TiO2, 84.3 wt% Al2O3, and 0.8 wt% SiO2. The specific surface area of ​​the support is 78 m². 2 / g, pore volume 0.45mL / g, crushing strength 196N / cm. The results are shown in Table 1.

[0085] Preparation Example 2

[0086] The selected material is a TiO2-Al2O3 composite oxide produced by Yantai Heng Hui Chemical Co., Ltd., containing 25wt% TiO2 and 75wt% Al2O3, with a specific surface area of ​​62m². 2 / g, pore volume 0.51mL / g.

[0087] 100g of TiO2-Al2O3 composite oxide was impregnated with 1L of a 5wt% hexadecyltrimethylammonium chloride methanol solution for 2h and then dried at 80℃ for 10h. 100g of a 5wt% triethoxysilane aqueous solution was then added dropwise to the dried composite oxide. After the addition was completed, the resulting mixture was stirred uniformly for 20 minutes. The mixture was then dried at 80℃ for 8h and calcined at 900℃ for 3h to obtain the modified composite oxide support B'.

[0088] The support contains 24.5 wt% TiO2, 73.5 wt% Al2O3, and 2.0 wt% SiO2. The specific surface area of ​​the support is 66 μm. 2 / g, pore volume is 0.41mL / g, and crushing strength is 220N / cm. The results are shown in Table 1.

[0089] Preparation Example 3

[0090] The selected material is a TiO2-Al2O3 composite oxide produced by Yantai Heng Hui Chemical Co., Ltd., containing 12wt% TiO2, 88wt% Al2O3, and a specific surface area of ​​66 μm. 2 / g, pore volume is 0.52mL / g.

[0091] 100g of TiO2-Al2O3 composite oxide was impregnated with 1L of a 5wt% tetradecyl dimethyl benzyl ammonium chloride methanol solution for 2h, and then dried at 90℃ for 9h. 100g of a 2.5wt% methyltriethoxysilane aqueous solution was added dropwise to the dried composite oxide. After the addition was completed, the resulting mixture was stirred evenly for 15 minutes. The composite oxide treated in this way was then dried at 90℃ for 9h and calcined at 750℃ for 6h to obtain the modified composite oxide support C'.

[0092] The support contains 11.9 wt% TiO2, 87.1 wt% Al2O3, and 1.0 wt% SiO2. The specific surface area of ​​the support is 72 μm. 2 / g, pore volume of 0.43mL / g, and crushing strength of 205N / cm. The results are shown in Table 1.

[0093] Preparation Example 4

[0094] The TiO2-Al2O3 composite oxide (TiO2 content 18wt%, Al2O3 content 82wt%, specific surface area 67m) produced by Yantai Heng Hui Chemical Co., Ltd. was selected. 2 / g, pore volume of 0.49mL / g), 100g of TiO2-Al2O3 composite oxide was impregnated with 1L of 5wt% dodecyl dimethyl benzyl ammonium chloride methanol solution for 2h, and then dried at 70℃ for 10h. 100g of 8wt% vinyltrimethoxysilane aqueous solution was added dropwise to the dried composite oxide. After the addition was completed, the resulting mixture was stirred evenly for 30 minutes. The composite oxide treated in this way was then dried at 150℃ for 5h and calcined at 650℃ for 6h to obtain the modified composite oxide support D'.

[0095] The support contains 17.5 wt% TiO2, 79.4 wt% Al2O3, and 3.1 wt% SiO2. The specific surface area of ​​the support is 88 μm. 2 / g, pore volume is 0.44mL / g, and crushing strength is 243N / cm. The results are shown in Table 1.

[0096] Preparation Example 5

[0097] The TiO2-Al2O3 composite oxide (TiO2 content 15wt%, Al2O3 content 85wt%, specific surface area 60m²) produced by Yantai Heng Hui Chemical Co., Ltd. was selected. 2 / g, pore volume 0.55mL / g, crushing strength 160N / cm), 100g of TiO2-Al2O3 composite oxide was impregnated with 1L of 5wt% hexadecyltrimethylammonium chloride methanol solution for 2h, and then dried at 60℃ for 12h. 100g of 1wt% vinyltrimethoxysilane aqueous solution was added dropwise to the dried composite oxide. After the addition was completed, the resulting mixture was stirred evenly for 20 minutes. The composite oxide treated in this way was then dried at 60℃ for 12h and calcined at 850℃ for 4h to obtain the modified composite oxide support E'.

[0098] The support contains 14.9 wt% TiO2, 84.7 wt% Al2O3, and 0.4 wt% SiO2. The specific surface area of ​​the support is 77 μm. 2 / g, pore volume 0.47mL / g, crushing strength 186N / cm. The results are shown in Table 1.

[0099] Preparation Example 6

[0100] The TiO2-Al2O3 composite oxide (TiO2 content 8wt%, Al2O3 content 92wt%, specific surface area 63m) produced by Yantai Heng Hui Chemical Co., Ltd. was selected. 2 / g, pore volume of 0.54mL / g), 100g of TiO2-Al2O3 composite oxide was impregnated with 1L of 5wt% octadecyl dimethyl benzyl ammonium chloride methanol solution for 2h, and then dried at 110℃ for 7h. 100g of 0.5wt% vinyltrimethoxysilane aqueous solution was added dropwise to the dried composite oxide. After the addition was completed, the resulting mixture was stirred evenly for 10 minutes. The composite oxide treated in this way was then dried at 110℃ for 7h and calcined at 850℃ for 4h to obtain the modified composite oxide support F'.

[0101] The support contains 8.0 wt% TiO2, 91.8 wt% Al2O3, and 0.2 wt% SiO2. The specific surface area of ​​the support is 88 μm. 2 / g, pore volume is 0.44mL / g, and crushing strength is 243N / cm. The results are shown in Table 1.

[0102] Comparative Preparation Example 1

[0103] The TiO2-Al2O3 carrier (TiO2 content 15wt%, Al2O3 content 85wt%, specific surface area 60m²) produced by Yantai Heng Hui Chemical Co., Ltd. was selected. 2 The material (g, pore volume 0.55 mL / g, crushing strength 160 N / cm) was not modified and was denoted as carrier G'. The results are shown in Table 1.

[0104] Comparative Preparation Example 2

[0105] γ-Al2O3 support (specific surface area 140m²) produced by Yantai Heng Hui Chemical Co., Ltd. was selected. 2 The material (with a pore volume of 0.65 mL / g and a crushing strength of 300 N / cm) was not modified and was denoted as carrier H'. The results are shown in Table 1.

[0106] Comparative preparation example 3

[0107] The TiO2-Al2O3 composite oxide (TiO2 content 15wt%, Al2O3 content 85wt%, specific surface area 60m²) produced by Yantai Heng Hui Chemical Co., Ltd. was selected. 2 / g, pore volume 0.55mL / g, crushing strength 160N / cm) 100g, 2wt% vinyltrimethoxysilane aqueous solution 100g was added dropwise to the composite oxide. After the addition was completed, the resulting mixture was stirred evenly for 10 minutes. The composite oxide treated in this way was then dried at 70℃ for 10h and calcined at 850℃ for 4h to obtain modified composite oxide carrier I'.

[0108] The support contains 15.0 wt% TiO2, 84.6 wt% Al2O3, and 0.4 wt% SiO2. The specific surface area of ​​the support is 75 μm. 2 / g, pore volume 0.40mL / g, crushing strength 178N / cm. The results are shown in Table 1.

[0109] Comparative preparation example 4

[0110] The TiO2-Al2O3 composite oxide (TiO2 content 15wt%, Al2O3 content 85wt%, specific surface area 60m²) produced by Yantai Heng Hui Chemical Co., Ltd. was selected. 2 / g, pore volume 0.55mL / g, crushing strength 160N / cm), 100g of TiO2-Al2O3 composite oxide was impregnated with 1L of 5wt% dimethyl dioctadecyl ammonium chloride methanol solution. After impregnation for 2h, it was dried at 70℃ for 10h and calcined at 850℃ for 4h to obtain the modified composite oxide carrier J'.

[0111] The support contains 15 wt% TiO2 and 85 wt% Al2O3. The specific surface area of ​​the support is 81 μm. 2 / g, pore volume is 0.49mL / g, and crushing strength is 168N / cm. The results are shown in Table 1.

[0112] Table 1

[0113]

[0114]

[0115] As shown in Table 1, the modified composite oxide provided by the present invention overcomes the disadvantage of low crushing strength caused by the introduction of TiO2 in metal composite oxides through modification, and significantly improves the crushing strength of the modified composite oxide.

[0116] Example 1

[0117] 72.8 g of the modified composite oxide support prepared in Preparation Example 1 was added to 628 mL of a solution containing 0.5 mol / L copper nitrate, 100 mL of 0.2 mol / L nickel nitrate, 20 mL of 0.075 mol / L ruthenium nitrate, and 50 mL of 0.21 mol / L potassium nitrate. The solution was impregnated at 25 °C for 180 min, dried at 110 °C for 6 h, and then calcined at 500 °C for 4 h to obtain the Cu-Ru-Ni-K / SiO2-TiO2-Al2O3 catalyst (supported catalyst A).

[0118] Example 2

[0119] 79.1 g of the modified composite oxide support prepared in Preparation Example 2 was added to 453 mL of a solution containing 0.5 mol / L copper nitrate, 100 mL of 0.29 mol / L nickel nitrate, 30 mL of 0.075 mol / L ruthenium nitrate, and 40 mL of 0.21 mol / L potassium nitrate. The solution was impregnated at 25 °C for 180 min, dried at 110 °C for 6 h, and then calcined at 500 °C for 4 h to obtain the Cu-Ru-Ni-K / SiO2-TiO2-Al2O3 catalyst (supported catalyst B).

[0120] Example 3

[0121] 81.8 g of the modified composite oxide support prepared in Preparation Example 3 was added to 440 mL of copper nitrate solution with a Cu content of 0.4 mol / L, 100 mL of nickel nitrate solution with a Ni content of 0.47 mol / L, 40 mL of ruthenium nitrate solution with a Ru content of 0.075 mol / L, and 30 mL of potassium nitrate solution with a K content of 0.21 mol / L. The solution was impregnated at 25 °C for 180 min, dried at 110 °C for 6 h, and then calcined at 500 °C for 4 h to obtain Cu-Ru-Ni-K / SiO2-TiO2-Al2O3 catalyst (supported catalyst C).

[0122] Example 4

[0123] 76.3 g of the modified composite oxide support prepared in Preparation Example 4 was added to 503 mL of a solution containing 0.5 mol / L copper nitrate, 100 mL of 0.41 mol / L nickel nitrate, 30 mL of 0.075 mol / L ruthenium nitrate, and 30 mL of 0.21 mol / L potassium nitrate. The solution was impregnated at 25 °C for 180 min, dried at 110 °C for 6 h, and then calcined at 500 °C for 4 h to obtain the Cu-Ru-Ni-K / SiO2-TiO2-Al2O3 catalyst (supported catalyst D).

[0124] Example 5

[0125] 73.85 g of the modified composite oxide support prepared in Preparation Example 5 was added to 628 mL of a solution containing 0.5 mol / L copper nitrate, 100 mL of 0.11 mol / L nickel nitrate, 10 mL of 0.075 mol / L ruthenium nitrate, and 25 mL of 0.21 mol / L potassium nitrate. The solution was impregnated at 25 °C for 180 min, dried at 110 °C for 6 h, and then calcined at 500 °C for 4 h to obtain the Cu-Ru-Ni-K / SiO2-TiO2-Al2O3 catalyst (supported catalyst E).

[0126] Example 6

[0127] 89.4 g of the modified composite oxide support prepared in Preparation Example 6 was added to 419 mL of copper nitrate with a Cu content of 0.15 mol / L, 334 mL of nickel nitrate with a Ni content of 0.2 mol / L, 50 mL of ruthenium nitrate with a Ru content of 0.075 mol / L, and 10 mL of potassium nitrate with a K content of 0.21 mol / L. The solution was impregnated at 25 °C for 180 min, dried at 110 °C for 6 h, and then calcined at 500 °C for 4 h to obtain the Cu-Ru-Ni-K / SiO2-TiO2-Al2O3 catalyst (supported catalyst F).

[0128] Comparative Examples 1-2

[0129] 72.8 g of the supports prepared in Comparative Preparation Examples 1 and 2 were respectively added to 628 mL of copper nitrate solution with Cu content of 0.5 mol / L, 100 mL of nickel nitrate solution with Ni content of 0.2 mol / L, 20 mL of ruthenium nitrate solution with Ru content of 0.075 mol / L, and 50 mL of potassium nitrate solution with K content of 0.21 mol / L. The solutions were impregnated at 25 °C for 180 min, dried at 110 °C for 6 h, and then calcined at 500 °C for 4 h to obtain catalysts G and H.

[0130] Comparative Examples 3-4

[0131] 89.4 g of the supports prepared in Comparative Preparation Examples 3 and 4 were respectively added to 419 mL of copper nitrate solution with a Cu content of 0.15 mol / L, 334 mL of nickel nitrate solution with a Ni content of 0.2 mol / L, 50 mL of ruthenium nitrate solution with a Ru content of 0.075 mol / L, and 10 mL of potassium nitrate solution with a K content of 0.21 mol / L. The solutions were impregnated at 25 °C for 180 min, dried at 110 °C for 6 h, and then calcined at 500 °C for 4 h to obtain catalysts I and J.

[0132] The catalysts prepared in Examples 1-6 and Comparative Examples 1-4 are shown in Table 2 (based on 100 parts by mass of the catalyst).

[0133] Table 2

[0134]

[0135] Supported catalyst A was characterized using the catalyst characterization methods described above. Figure 1 ,from Figure 1 It can be seen that the active component particles are uniformly distributed on the carrier, and the particle size of the nano clusters formed by the active components on the carrier surface is in the range of 3 to 5 nm.

[0136] Test Example 1

[0137] The composition of the cracked C4 from a certain factory used as raw material in this test example is shown in Table 3.

[0138] Hydrogenation was carried out in a fixed-bed reactor. The upper and lower beds of the reactor were loaded with the catalyst prepared in the example, and the mass ratio of the upper to lower bed catalyst is shown in Table 4. Hydrogenation was performed by continuously adding butadiene-containing cracked C4 feedstock, with top feed and bottom discharge. During the experiment, the operating conditions were as follows: reaction temperature 30°C, reaction pressure 1.5 MPa, and fresh feed weight hourly space velocity (WHSV) of cracked C4 3 h⁻¹. -1The hydrogenation reaction was carried out continuously for 200 hours with a cycle ratio of 20 and a hydrogen / butadiene molar ratio of 3. The hydrogenation evaluation results are shown in Table 4.

[0139] Table 3 Composition of raw materials

[0140] Composition wt% Isobutane 0.3 butane 2.9 Butene-1 11.9 Isobutylene 22.4 Butene-2 11.8 butadiene 48.2 other 2.6

[0141] Table 4. Evaluation Results of Hydrogenation

[0142]

[0143] In Table 4, the selectivity of butene-1 is calculated as [(exit butene-1 - inlet butene-1) / (inlet butadiene - outlet butadiene)] × 100%.

[0144] As shown in Table 4, the non-precious metal dimethyl maleate selective hydrogenation catalyst provided by the present invention has the advantages of high selectivity and high low-temperature activity.

[0145] The above description of the embodiments is provided to enable those skilled in the art to understand and apply the present invention. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the embodiments described herein, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A selective hydroisomerization catalyst for C4 fractions, characterized in that, Includes the carrier and the active components loaded on the carrier. The carrier is a metal composite oxide modified with organic cationic quaternary ammonium salt and silane reagents; the metal composite oxide contains metal element I, which includes aluminum and titanium; The active component contains metal element II, which includes the main active component Cu and optional auxiliary active components, including Ni, Ru and alkali metals.

2. The catalyst according to claim 1, characterized in that, The organic cationic quaternary ammonium salt includes a hydrocarbon-based quaternary ammonium salt, preferably, the hydrocarbon-based quaternary ammonium salt has the general formula R4N. + X - , where X - Selected from halide ions and acid radical ions, preferably, the halide ions include F. - Cl - ,Br - and I - The acid radical ions include nitrate ions and carboxylate ions, with the general formula R4N. + X - Each R in the R may be the same or different, and each is independently selected from alkyl, cycloalkyl, aryl, aralkyl and alkylaryl, with at least one R, preferably 1 to 2 Rs selected from alkyl groups of C6 or above, preferably from C6 to 20 alkyl groups, and the remaining Rs are preferably selected from C1 to C4 alkyl groups and C7 to C11 aralkyl groups; Preferably, the organic cationic quaternary ammonium salt includes at least one of di(octadecyl)dimethyl quaternary ammonium salt, hexadecyltrimethyl quaternary ammonium salt, and C12-18 alkyldimethylbenzyl quaternary ammonium salt; More preferably, the organic cationic quaternary ammonium salt is selected from at least one of dioctadecyl dimethyl ammonium chloride, hexadecyl trimethyl ammonium chloride, hexadecyl trimethyl ammonium bromide, dodecyl dimethyl benzyl ammonium chloride, tetradecyl dimethyl benzyl ammonium chloride, hexadecyl dimethyl benzyl ammonium chloride, and octadecyl dimethyl benzyl ammonium chloride; and / or The general formula of the silane reagent is SiR 1 x (OR 2 ) y Where x and y are each independently selected from integers from 1 to 3, x + y = 4, R 1 Selected from hydrogen, C1-C6 alkyl and C2-C6 alkenyl, R 2 Selected from C1 to C6 alkyl groups; Preferably, the silane reagent comprises at least one of triethoxysilane, trimethoxysilane, methyltriethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane; and / or The amount of the organic cationic quaternary ammonium salt is 1%-50% of the mass of the metal composite oxide, preferably 30%-50%, more preferably 35%-50%; and / or The amount of the silane reagent used is 0.5%-30% of the mass of the metal composite oxide, preferably 0.5%-15%, more preferably 0.5%-10%; and / or The alkali metal is selected from at least one of lithium, sodium, potassium, and rubidium.

3. The catalyst according to claim 1 or 2, characterized in that, The metal composite oxide is an Al2O3-TiO2 composite oxide; preferably, based on the Al2O3-TiO2 composite oxide, the content of Ti in the Al2O3-TiO2 composite oxide, calculated as TiO2, is 5-30 wt%, more preferably 8 wt%-25 wt%; the content of Al in the Al2O3 composite oxide, calculated as Al, is 70 wt%-95 wt%, more preferably 75 wt%-92 wt%; and / or The support is a SiO2-TiO2-Al2O3 composite oxide. Preferably, based on the support, the content of Ti (calculated as TiO2) in the support is 5wt% to 25wt%, the content of Al (calculated as Al2O3) is 65wt% to 90wt%, preferably 80wt% to 90wt%, and the content of Si (calculated as SiO2) is 0.5wt% to 15wt%; and / or Based on 100 parts by mass of the catalyst, the catalyst contains 5-25 parts of Cu (calculated as CuO), 0-1 parts of Ru (calculated as its oxide), preferably 0.1-0.5 parts, 0-5 parts of Ni (calculated as its oxide), preferably 0.1-5 parts, 0-1 parts of alkali metal (calculated as its oxide), preferably 0.1-0.5 parts, and 70-95 parts of support; and / or The active component is distributed on the support in the form of nanoclusters, wherein the particle size of the nanoclusters is less than 5 nm; and / or The specific surface area of ​​the carrier is 30–150 μm. 2 / g, preferably 50-90m 2 / g; and / or The pore volume of the carrier is 0.2–0.8 mL / g, preferably 0.3–0.5 mL / g. 2 / g; and / or In the catalyst, the main active component and the co-active component each exist independently in the form of their elemental form or oxide.

4. The catalyst according to any one of claims 1-3, characterized in that, The preparation of the carrier includes the following steps: The metal composite oxide was first treated with an organic cationic quaternary ammonium salt solution, and the treated metal composite oxide was then treated with a silane reagent to obtain the carrier. Preferably, the first treatment includes a first impregnation and a first drying performed sequentially; and / or, the second treatment includes adding a solution of a silane reagent dropwise onto the first-treated metal composite oxide, followed by stirring, a second drying, and a first calcination, preferably with a stirring time of 1 min to 60 min; Preferably, the concentration of the organic cation quaternary ammonium salt solution is 0.1 wt% to 10 wt%, more preferably 0.2 to 10 wt%, and even more preferably 1 to 5 wt%. Preferably, the solvent of the organic cationic quaternary ammonium salt solution includes at least one selected from water, methanol, ethanol, benzene, toluene, isopropanol, acetone, sulfuric acid, hydrochloric acid, nitric acid, sodium hydroxide, and potassium hydroxide. Preferably, the silane reagent solution is an aqueous solution of the silane reagent with a concentration of 0.1–10 wt%, more preferably 1–10 wt%.

5. The catalyst according to any one of claims 1-4, characterized in that, The conditions for the first impregnation include: an impregnation temperature of 10°C to 50°C, an impregnation time of 1 hour to 12 hours, preferably 1 hour to 8 hours; and / or The conditions for the first and second drying processes each independently include: a drying temperature of 60°C to 150°C, preferably 60°C to 110°C, and a drying time of 4 hours to 12 hours; and / or The conditions for the first roasting include: a roasting temperature of 300–1100℃, preferably 500–900℃, and a roasting time of 4–12 hours.

6. A method for preparing a C4 fraction selective hydroisomerization catalyst according to any one of claims 1-5, characterized in that, The process includes the following steps: second impregnating the support with a copper salt solution, optionally a nickel salt solution, optionally a ruthenium salt solution, and optionally an alkali metal salt solution; and then subjecting the impregnated support to a third drying and second calcination to obtain the catalyst.

7. The preparation method according to claim 6, characterized in that, The copper salt includes at least one of copper sulfate, nitrate, soluble carboxylate, hypophosphite, and halide, preferably at least one of copper sulfate, copper nitrate, copper chloride, and copper acetate; and / or The nickel salt includes at least one of nickel nitrate, soluble carboxylate, and halide, preferably at least one of nickel nitrate, hydrochloride, oxalate, and acetate; and / or The ruthenium salt includes at least one of ruthenium nitrate, soluble carboxylate, and halide, preferably at least one of ruthenium nitrate, hydrochloride, oxalate, and acetate; and / or The alkali metal salt is selected from at least one of lithium, sodium, potassium, and rubidium salts; and / or The solvents in the copper salt solution, nickel salt solution, ruthenium salt solution, and alkali metal salt solution are each independently at least one selected from water, methanol, ethanol, benzene, toluene, and chloroethane; and / or The concentration of the copper salt solution is 0.1–0.6 mol / L; and / or The concentration of the nickel salt solution is 0.1–0.3 mol / L; and / or The concentration of the ruthenium salt solution is 0.01–0.1 mol / L; and / or The concentration of the alkali metal salt solution is 0.1–0.3 mol / L.

8. The preparation method according to claim 6 or 7, characterized in that, The conditions for the second impregnation include: a temperature of 20°C to 70°C, preferably 20°C to 40°C, and a time of 1 hour to 12 hours, preferably 1 hour to 4 hours; and / or The conditions for the third drying include: a temperature of 60–150°C, preferably 100–150°C, and a time of 1–8 hours, preferably 4–8 hours; and / or The conditions for the second roasting include: a temperature of 300–600°C, preferably 400–500°C, and a time of 4–12 hours.

9. The application of the C4 fraction selective hydroisomerization catalyst according to any one of claims 1-5 or the C4 fraction selective hydroisomerization catalyst prepared by the preparation method according to claims 6-8 in the selective hydrogenation of C4 fractions to remove butadiene and to produce 1-butene, preferably, the selective hydrogenation conditions include: The reaction temperature is 20℃~40℃, the molar ratio of hydrogen to alkyne is 1~2.5:1, the pressure is 0.5MPa~0.8MPa, and the recycle ratio is 10~30:1; and / or, the catalyst is divided into upper and lower layers of composite packing, and the weight ratio between the upper catalyst layer and the lower catalyst layer is 1~3:

1.

10. A method for selective hydrogenation of C4 fractions to remove butadiene and produce 1-butene, using the C4 fraction selective hydrogenation catalyst according to any one of claims 1-5 or the C4 fraction selective hydrogenation catalyst prepared by any one of claims 6-8 as the catalyst, preferably, the selective hydrogenation conditions include: The reaction temperature is 20℃~40℃, the molar ratio of hydrogen to alkyne is 1~2.5:1, the pressure is 0.5MPa~0.8MPa, and the recycle ratio is 10~30:1; and / or, the catalyst is divided into upper and lower layers of composite packing, and the weight ratio between the upper catalyst layer and the lower catalyst layer is 1~3:1.

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