Catalyst for selective hydrogenation of cyclopentadiene as well as preparation method and application of catalyst

Abstract

The invention discloses a catalyst for selective hydrogenation of cyclopentadiene and a preparation method and application thereof, the catalyst comprises an Al2O3-CuO-TiO2 composite oxide carrier, a main active component Ni and an optional auxiliary active component, the main active component Ni and the optional auxiliary active component are loaded on the Al2O3-CuO-TiO2 composite oxide carrier, and the auxiliary active component is selected from at least one of Ag and Ru. The catalyst provided by the invention has high low-temperature reaction activity and selectivity, is simple in preparation process, mild in reaction condition and low in production cost, can stably operate for a long time in production, and has industrial application value.

Description

Technical Field

[0001] The invention relates to a catalyst for selective hydrogenation of cyclopentadiene and a preparation method and application thereof. Background Art

[0002] At present, my country's annual ethylene production has exceeded 20 million tons. The C5 and C9 fractions of ethylene cracking contain a large amount of dicyclopentadiene, and the potential annual production of dicyclopentadiene has exceeded 1 million tons. However, most of the current dicyclopentadiene is directly burned as low-value-added fuel oil, which not only wastes resources but also causes environmental pollution. Dicyclopentadiene can be heated and depolymerized to produce its monomer cyclopentadiene, and cyclopentadiene can be selectively hydrogenated to produce multi-purpose monoolefins - cyclopentene. This is a high-value-added utilization of dicyclopentadiene resources.

[0003] Cyclopentene is an important organic chemical raw material and can be used to prepare important organic chemical intermediates and products such as cyclopentanol, cyclopentanone, glutaraldehyde, glutaric acid, cyclopentane, halogenated cyclopentane and polycyclopentene rubber.

[0004] The method for preparing cyclopentene by selective hydrogenation of cyclopentadiene has the characteristics of sufficient raw materials and good economy, and can produce cyclopentene in large quantities. It is a process technology with strong application and development prospects.

[0005] The technical difficulty of preparing cyclopentene by selective hydrogenation of cyclopentadiene is to control the hydrogenation depth of cyclopentadiene, that is, it is necessary to avoid full hydrogenation to generate cyclopentane as much as possible, so as to improve the selectivity of hydrogenation reaction to cyclopentene. In addition, since the boiling points of the byproduct cyclopentane of deep hydrogenation and the target product cyclopentene are relatively close, the separation of the two is not easy, and the energy consumption of the distillation process is relatively high. Based on the above reasons, it is required that the selectivity of the hydrogenation catalyst to cyclopentene is as good as possible, and the catalytic activity is as high as possible. In addition, in the hydrogenation reaction of cyclopentadiene, the cyclopentadiene adsorbed on the catalyst surface is very easy to dimerize, and then repolymerize to form a polymer, i.e., the generation process of the so-called "green oil", which causes the catalyst to need frequent regeneration, shortens the service life and greatly affects the long-term stable operation of the device. Accordingly, it is required that the catalyst has high low-temperature activity, a large "green oil" capacity, and has high stability. Obviously, the key to the technology of preparing cyclopentene by selective hydrogenation of cyclopentadiene lies in the selection of high-performance catalysts.

[0006] In the prior art, the selective hydrogenation catalyst for preparing cyclopentene by hydrogenation of cyclopentadiene is typically a carrier-supported Pd catalyst, the carrier usually uses alumina, and an additive is often used to modify the Pd active component in this type of catalyst. The catalyst is easy to lose, expensive, difficult to regenerate, and has unsatisfactory selectivity.

[0007] In the prior art, Ni catalysts have also been reported in the method of selective hydrogenation of cyclopentadiene, and the typical one is Raney-Ni catalyst. However, Raney-Ni is a skeleton Ni-Al alloy catalyst, which is mostly used in slurry bed reactions. It is often dispersed in the raw material in powder form to violently disturb the contact reaction. It has poor strength, is easy to crush and lose, and is easy to spontaneously ignite when exposed to air. It is not convenient to store and separate from the product after the reaction. In addition, while ensuring a high selectivity for cyclopentene, the hydrogenation activity of cyclopentadiene is low, and the raw material conversion rate is usually less than 90%.

[0008] The Ni catalyst supported by the carrier is very suitable for fixed bed reaction due to its large particles, high mechanical strength, large pore volume and large specific surface area. Therefore, there is no problem of difficult separation of catalyst and product, which can greatly simplify the hydrogenation process. However, there are few reports on related technologies and the use effect is poor. In addition, although the Ni catalyst supported by the carrier has many advantages over the more typical Pd catalyst and Raney-Ni catalyst supported by the carrier, it still has the problems of insufficient selectivity and low temperature reaction activity and poor stability in the selective hydrogenation process of cyclopentadiene.

[0009] Therefore, it is necessary to develop a catalyst for the selective hydrogenation of cyclopentadiene to prepare cyclopentene, which has high low-temperature reaction activity, good selectivity, simple process, mild reaction conditions, low production cost, and can operate stably for a long time. Summary of the invention

[0010] In view of this, in order to overcome at least one technical problem existing in the prior art, the present invention provides a catalyst for selective hydrogenation of cyclopentadiene, and a preparation method and application thereof.

[0011] The objectives of the present invention are achieved through the following technical solutions.

[0012] In a first aspect, the present invention provides a catalyst for the selective hydrogenation of cyclopentadiene, wherein the catalyst comprises an Al2O3-CuO-TiO2 composite oxide carrier and a main active component Ni and an optional auxiliary active component loaded thereon, wherein the auxiliary active component is selected from at least one of Ag and Ru.

[0013] In the present invention, a catalyst for selective hydrogenation of cyclopentadiene is obtained by combining a specific carrier, a main active component and an auxiliary active component, and the catalyst has high low-temperature reaction activity and selectivity.

[0014] According to the catalyst provided by the present invention, based on 100 parts by weight of the composite oxide carrier, the content of CuO is 0.1 to 5 parts, the content of TiO2 is 5 to 25 parts, and the content of Al2O3 is 70 to 94.9 parts.

[0015] In some embodiments, based on 100 parts by weight of the composite oxide support, the content of CuO is 0.3 to 3 parts, the content of TiO2 is 9 to 20 parts, and the content of Al2O3 is 77 to 90.7 parts; and in some embodiments, based on 100 parts by weight of the composite oxide support, the content of CuO is 1.5 to 3 parts, the content of TiO2 is 12 to 18 parts, and the content of Al2O3 is 79 to 86.5 parts.

[0016] According to the catalyst provided by the present invention, based on the total weight of the catalyst as 100 parts by weight, the content of the main active component Ni is 5 to 25 parts in terms of NiO, preferably 10 to 20 parts, more preferably 10 to 15 parts, and most preferably 10 to 12 parts; the content of the auxiliary active component is 0 to 5 parts in terms of oxide, preferably 0.5 to 3 parts, more preferably 1 to 3 parts, and most preferably 2 to 3 parts; the content of the composite oxide is 70 to 95 parts, preferably 79.5 to 87 parts, more preferably 82 to 87 parts, and most preferably 85 to 87 parts.

[0017] According to the catalyst provided by the present invention, the specific surface area of ​​the composite oxide carrier is 30 to 155 m 2 / g, preferably 55 to 85m 2 / g, more preferably 55 to 70 m 2 / g.

[0018] According to the catalyst provided by the present invention, the pore volume of the composite oxide carrier is 0.2 to 0.8 mL / g, preferably 0.3 to 0.4 mL / g.

[0019] According to the catalyst provided by the present invention, the catalyst is an activated catalyst. In some embodiments, the activation treatment is carried out under hydrogen conditions.

[0020] According to the catalyst provided by the present invention, the main active component Ni and the auxiliary active component can exist in the form of atoms or compounds independently of each other. Such compounds can be compounds of the main active component Ni and the auxiliary active component commonly used in nickel-based catalysts for selective hydrogenation. In some embodiments, the main active component Ni and the auxiliary active component exist in the form of oxides independently of each other, such as NiO, Ag2O, RuO2.

[0021] In a second aspect, the present invention provides a method for preparing the catalyst of the first aspect, wherein the preparation method comprises the following steps:

[0022] S110, impregnating the Al2O3-CuO-TiO2 composite oxide support with a nickel salt solution to obtain an impregnated composite oxide support, and drying and calcining the impregnated composite oxide support to obtain a catalyst precursor;

[0023] Optionally, S120, the catalyst precursor is impregnated with a salt solution of an auxiliary active component to obtain an impregnated catalyst precursor, and the impregnated catalyst precursor is dried and calcined to obtain a catalyst.

[0024] According to the preparation method provided by the present invention, the time of the immersion treatment in steps S110 and S120 is independently 1 to 8 hours, preferably 1 to 4 hours.

[0025] According to the preparation method provided by the present invention, the conditions for the drying treatment in steps S110 and S120 independently include: a drying temperature of 90 to 120° C.; and / or a drying time of 2 to 8 hours.

[0026] According to the preparation method provided by the present invention, the conditions for the calcination treatment in steps S110 and S120 independently include: a calcination temperature of 300 to 800° C.; and / or a calcination time of 2 to 10 hours.

[0027] According to the preparation method provided by the present invention, examples of the nickel salt include, but are not limited to, nickel sulfate, nitrate, soluble carboxylate, hypophosphite and halide. In some embodiments, the nickel salt is nickel sulfate, nickel nitrate, nickel chloride or nickel acetate.

[0028] According to the preparation method provided by the present invention, the present invention has no particular restrictions on the type of nickel salt solution, which can be an aqueous solution or an organic nickel salt solution formed by ethanol, benzene, etc. as a solvent, preferably an aqueous solution of an inorganic nickel salt. Compared with an organic nickel salt solution, an aqueous solution of an inorganic nickel salt has low cost and is green and environmentally friendly.

[0029] According to the preparation method provided by the present invention, the concentration of the nickel salt solution is 1.0-3.0 mol / L, calculated as NiO.

[0030] According to the preparation method provided by the present invention, the salt of the co-active component can be a salt of the co-active component commonly used in the field of catalysts for selective hydrogenation, examples of which include but are not limited to: nitrates, soluble carboxylates and soluble halides of the co-active component, preferably nitrates, hydrochlorides, oxalates or acetates.

[0031] According to the preparation method provided by the present invention, the present invention has no particular restrictions on the type of salt solution of the auxiliary active component, which can be an aqueous solution, or an organic salt solution formed by ethanol, benzene, etc. as a solvent, preferably an inorganic salt solution of the auxiliary active component. Compared with the organic salt solution, the inorganic salt solution has low cost and is green and environmentally friendly. For example, the salt of the auxiliary active component can be silver nitrate or ruthenium nitrate.

[0032] According to the preparation method provided by the present invention, the concentration of the salt solution of the co-active component is 0.01-0.3 mol / L in terms of the metal oxide.

[0033] According to the preparation method provided by the present invention, the preparation method of the composite oxide support comprises:

[0034] S210, adding a copper salt solution, a titanium salt solution and an alkaline solution to an aluminum salt solution in parallel at a temperature of 50 to 90° C., and after staying at a pH value of 5.5 to 7.0 for 15 to 20 minutes, continuing to add an alkaline solution until the pH value reaches 8 to 10, and staying for 15 to 20 minutes to obtain a precipitate;

[0035] S220, washing, drying and calcining the precipitate to obtain a composite oxide support.

[0036] According to the preparation method provided by the present invention, in step S210, by adjusting the pH value, several solutions can be fully mixed. Further, by continuing to add alkaline solution to a pH value of 8 to 10, the precipitation can be more thorough and the utilization rate of the metal can be improved; at the same time, the pore structure can be optimized to obtain a moderate pore volume and specific surface area.

[0037] According to the preparation method provided by the present invention, the aluminum salt is selected from aluminum sulfate, aluminum chloride, aluminum nitrate and organic aluminum salt, and / or the concentration of the aluminum salt solution is 0.5-2.5 mol / L.

[0038] According to the preparation method provided by the present invention, the titanium salt solution is selected from the acid solution of a soluble titanium salt of metatitanic acid, titanium tetrachloride, and tetraethyl titanate, such as a sulfuric acid solution; and / or the concentration of the titanium salt solution is 0.2 to 1.2 mol / L.

[0039] According to the preparation method provided by the present invention, the copper salt is a soluble copper salt, preferably selected from copper chloride, copper sulfate and copper nitrate; and / or the concentration of the copper salt aqueous solution is 0.1-0.6 mol / L.

[0040] According to the preparation method provided by the present invention, the alkaline solution comprises an ammonium salt solution and an alkaline solution. The ammonium salt is selected from ammonium bicarbonate, ammonium carbonate and an organic ammonium salt; and / or the concentration of the ammonium salt in the alkaline solution is 0.1 to 0.3 mol / L.

[0041] Similarly, the alkali solution is selected from ammonia water, sodium hydroxide, potassium hydroxide and organic base, and / or the concentration of the alkali solution is 0.2-0.4 mol / L.

[0042] According to the preparation method provided by the present invention, the precipitate washing process in step S220 includes washing with deionized water until no acid ions are detected.

[0043] According to the preparation method provided by the present invention, the drying conditions in step S220 include: a drying temperature of 100 to 150° C. and a drying time of 4 to 12 hours.

[0044] According to the preparation method provided by the present invention, the calcination conditions in step S220 include: a calcination temperature of 500 to 1100° C. and a calcination time of 4 to 12 hours.

[0045] According to the preparation method provided by the present invention, the preparation method of the titanium salt solution comprises: dissolving a soluble titanium salt such as metatitanic acid, titanium tetrachloride, and tetraethyl titanate in a sulfuric acid solution to form a titanium salt solution.

[0046] According to the preparation method provided by the present invention, the preparation method further comprises activating the catalyst obtained in step S120.

[0047] In some embodiments, the preparation method further comprises:

[0048] S310, using hydrogen to activate the catalyst obtained in step S120.

[0049] Preferably, the conditions for the activation treatment in step S310 include: an activation temperature of 300 to 600° C., an activation pressure of 0 to 3.0 MPa, a flow rate of hydrogen relative to the catalyst of 1 to 15 mL / min·g, and an activation time of 6 to 18 h.

[0050] In a third aspect, the present invention provides a catalyst prepared by the preparation method of the second aspect.

[0051] In a fourth aspect, the present invention provides use of the catalyst of the first aspect or the third aspect in the selective hydrogenation of cyclopentadiene to prepare cyclopentene.

[0052] In a fifth aspect, the present invention provides a method for preparing cyclopentene by selective hydrogenation of cyclopentadiene, wherein the method comprises: mixing cyclopentadiene and a diluent solvent, and allowing the cyclopentadiene and hydrogen to undergo a hydrogenation reaction in the presence of the catalyst to generate cyclopentene.

[0053] According to the method provided by the present invention, the dilution solvent is selected from alkanes such as n-heptane, isooctane, and cyclohexane, and is preferably selected from n-heptane and isooctane.

[0054] According to the method provided by the present invention, the conditions of the hydrogenation reaction include: a reaction temperature of 20 to 70°C, a reaction pressure of 0.1 to 1.5 MPa, a feed volume space velocity of 0.5 to 15 h -1 The molar ratio of cyclopentadiene to hydrogen is 1:(1.0-3.0), and the volume ratio of cyclopentadiene to the dilution solvent is 1:(0.1-20).

[0055] In some embodiments, the conditions of the hydrogenation reaction include: a reaction temperature of 25 to 40°C, a reaction pressure of 0.2 to 1.0 MPa, and a feed volume space velocity of 1 to 8 h -1 The molar ratio of cyclodiene to hydrogen is 1:(1.1-1.5), and the volume ratio of cyclopentadiene to the dilution solvent is 1:(0.5-10).

[0056] The present invention has the following advantages:

[0057] (1) The catalyst of the present invention has high low-temperature reaction activity and selectivity, a simple preparation process, mild reaction conditions, low production cost, and can operate stably for a long time in production, and has industrial application value.

[0058] (2) The Al2O3-CuO-TiO2 composite oxide used in the present invention has titanium oxide and aluminum oxide uniformly mixed and enriched on the surface of the composite oxide, and CuO is uniformly dispersed on the composite oxide skeleton structure. The inventors were surprised to find that a strong interaction is formed between Al2O3, CuO and TiO2 at high temperatures, so the composite oxide has high thermal stability, which overcomes the defect that copper alone is unstable at high temperatures. Furthermore, TiO2 can still maintain the active phase of anatase when calcined at a high temperature of 700 to 1000°C, ensuring the activity of the catalyst. In addition, it is believed that Al2O3 can maintain the crystal phase of γ-Al2O3, ensure the crushing strength and pore structure of the catalyst, and meet the needs of industrial applications.

[0059] (3) The catalyst for selective hydrogenation of cyclopentadiene to prepare cyclopentene provided by the present invention has the characteristics of high selectivity and low-temperature activity, large capacity of "green oil", stable hydrogenation activity, long-term use, convenient regeneration, continuous operation and easy separation from the product. The method for selective hydrogenation of cyclopentadiene to prepare cyclopentene using the catalyst has the characteristics of simple process, mild reaction conditions, low production cost and long-term stable operation. The use of the catalyst under the process conditions of the present invention can ensure excellent cyclopentadiene selective hydrogenation effect. DETAILED DESCRIPTION

[0060] The present invention will be further described below in conjunction with specific embodiments, but they do not constitute any limitation to the present invention.

[0061] Example 1

[0062] Preparation of vector

[0063] Prepare 1 L of 0.8 mol / L aluminum sulfate deionized water solution, 0.5 L of 0.46 mol / L metatitanic acid dilute sulfuric acid solution, 0.1 L of 0.39 mol / L copper nitrate solution, mix 0.22 mol / L ammonium bicarbonate solution with 25% ammonia water to prepare 1 L of mixed alkaline solution with a pH of 11-12.

[0064] At a temperature of 65°C, 0.1L of copper nitrate solution and 0.5L of dilute sulfuric acid solution of titanic acid were added to the above-mentioned deionized aluminum sulfate solution in parallel, and an appropriate amount of mixed alkali solution was added to keep the pH value of the mixed solution system at 6.2, and the mixture was kept for 20 minutes; the mixed alkali was continued to be added to make the pH = 9.1, and the mixture was kept for 20 minutes to obtain a precipitate, which was filtered to obtain a filter cake.

[0065] The filter cake was washed repeatedly 5 times with 20 times the volume of deionized water, dried at 110°C for 6 h, and calcined at 860°C for 5 h to obtain Al2O3-CuO-TiO2 composite oxide support A.

[0066] Example 2

[0067] Prepare 1 L of 0.88 mol / L aluminum sulfate deionized water solution, 0.5 L of 0.35 mol / L metatitanic acid dilute sulfuric acid solution, 0.13 L of 0.2 mol / L copper nitrate solution, mix 0.22 mol / L ammonium bicarbonate solution with 25% ammonia water to prepare 1 L of mixed alkaline solution with a pH of 11-12.

[0068] At a temperature of 75°C, copper nitrate solution and dilute sulfuric acid solution of metatitanic acid were added to the deionized aluminum sulfate solution in parallel, and an appropriate amount of mixed alkali solution was added to keep the pH value of the mixed solution system at 6.8, and the mixture was kept for 15 minutes; the mixed alkali solution was continued to be added to make the pH value = 8.5, and the mixture was kept for 15 minutes to obtain a precipitate, which was filtered to obtain a filter cake.

[0069] The filter cake was washed repeatedly 7 times with 30 times the volume of deionized water, dried at 120°C for 6 h, and calcined at 950°C for 4 h to obtain Al2O3-CuO-TiO2 composite oxide support B.

[0070] Example 3

[0071] The steps are basically the same as those in the preparation method of the carrier in Example 1, except that the concentrations of the solutions are different. Specifically, 1 L of a 0.9 mol / L aluminum sulfate deionized water solution, 0.5 L of a 0.25 mol / L metatitanic acid dilute sulfuric acid solution, and 0.1 L of a 0.1 mol / L copper nitrate solution are prepared. The Al2O3-CuO-TiO2 composite oxide carrier C is obtained.

[0072] Example 4

[0073] The steps are basically the same as those in the preparation method of the carrier in Example 1, except that the concentrations of the solutions are different. Specifically, 1 L of a 0.8 mol / L aluminum sulfate deionized water solution, 0.5 L of a 0.55 mol / L metatitanic acid dilute sulfuric acid solution, and 0.05 L of a 0.1 mol / L copper nitrate solution are prepared. The Al2O3-CuO-TiO2 composite oxide carrier D is obtained.

[0074] Example 5

[0075] The steps are basically the same as those in the preparation method of the carrier in Example 1, except that the concentrations of the solutions are different. Specifically, 1 L of a 0.9 mol / L aluminum sulfate deionized water solution, 0.4 L of a 0.2 mol / L metatitanic acid dilute sulfuric acid solution, and 0.4 L of a 0.2 mol / L copper nitrate solution are prepared. Al2O3-CuO-TiO2 composite oxide carrier E is obtained.

[0076] Example 6

[0077] The steps are basically the same as those in the preparation method of the carrier in Example 1, except that the concentrations of the solutions are different. Specifically, 1 L of a 0.8 mol / L aluminum sulfate deionized water solution, 0.5 L of a 0.75 mol / L metatitanic acid dilute sulfuric acid solution, and 0.015 L of a 0.1 mol / L copper nitrate solution are prepared. The Al2O3-CuO-TiO2 composite oxide carrier F is obtained.

[0078] Comparative Example 1

[0079] 1. Preparation of Vector

[0080] 1 L of deionized aluminum sulfate solution with a concentration of 0.8 mol / L was prepared, 0.56 L of dilute sulfuric acid solution of titanic acid with a concentration of 0.46 mol / L was prepared, and 0.22 mol / L ammonium bicarbonate solution was mixed with 25% ammonia water to prepare a mixed alkaline solution with a pH of 11-12.

[0081] Under normal pressure and temperature of 65°C, three solutions of aluminum sulfate deionized water solution, metatitanic acid dilute sulfuric acid solution and mixed alkali solution were co-precipitated in parallel. The flow rate of the mixed alkali solution was controlled to keep the pH value of the precipitate in the range of 5.0-6.0 for 8 minutes, and then the flow rate of the mixed alkali solution was increased to keep the pH value of the mixed solution in the range of 8.5-9.5 for 8 minutes, and then the flow rate of the mixed alkali solution was reduced to keep the pH value of the mixed solution in the range of 5.0-6.0 for 8 minutes, and then the flow rate of the mixed alkali solution was increased to keep the pH value of the precipitate in the range of 8.5-9.5, and this process was repeated until all the solutions were added. The reaction solution was allowed to stand at 70°C for 30 minutes, filtered, and the filter cake was washed with deionized water 15 times the volume of the filter cake for 30 minutes, filtered again, and washed again. This process was repeated four times, and finally the filter cake was dried at 110°C for 10 hours and calcined at 950°C for 5 hours to obtain titanium oxide-aluminum oxide composite G.

[0082] Comparative Example 2

[0083] 97g of γ-Al2O3 produced by Yantai Henghui Company was impregnated in 0.1L of 0.38mol / L copper nitrate solution for 4h, dried at 110℃ for 8h, and calcined at 550℃ for 5h. Al2O3 with a CuO content of 3% was obtained. 3- CuO composite oxide support H.

[0084] Comparative Example 3

[0085] γ-Al2O3 produced by Yantai Henghui Company was used as a carrier, which is denoted as carrier I.

[0086] Vector characterization

[0087] 1. Specific surface area and pore volume

[0088] The specific surface area and pore volume of the carrier were determined using the ASAP 2020 adsorption instrument (N2 adsorption-desorption method) from Mack Instruments, USA. Specifically, the carrier sample was degassed at 623K for 4 hours before the test, nitrogen was adsorbed at liquid nitrogen temperature, the sample data was processed using AMSM software, and the specific surface area of ​​the sample was obtained using the Brunauer-Emmet-Teller (BET) method. The average pore size was obtained based on the nitrogen adsorption isotherm curve using the Barrett-Joyner-Halenda (BJH) method, and the pore volume was obtained using the P / Po single-point desorption curve. The results are shown in Table 1.

[0089] 2. Determination of carrier components

[0090] UV-2100 ultraviolet spectrophotometer was used to measure the components in the carrier. The results are shown in Table 1.

[0091] Table 1 Carrier parameters of Examples 1 to 6 and Comparative Examples 1 to 3

[0092]

[0093] Example 7

[0094] A method for preparing Ni / Al2O3-CuO-TiO2 catalyst.

[0095] Take 100 g of the Al2O3-CuO-TiO2 composite oxide carrier A prepared in Example 1, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 2 h, dry it at 110°C for 6 h, and then calcine it at 500°C for 4 h to obtain catalyst A1 with a NiO content of 10.6 parts by weight.

[0096] Example 8

[0097] The catalyst was prepared according to the preparation method of the Ni / Al2O3-CuO-TiO2 catalyst in Example 7, with the only difference being that the Al2O3-CuO-TiO2 composite oxide carriers B, C, and D prepared above were taken respectively, and the concentration of the nickel nitrate solution was changed to prepare catalysts B1, C1, and D1 with different Ni contents.

[0098] Example 9

[0099] A method for preparing a Ni-Ag / Al2O3-CuO-TiO2 catalyst.

[0100] Take 100 g of the Al2O3-CuO-TiO2 composite oxide carrier A prepared in Example 1, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 1.5 h, dry it at 110°C for 6 h, and then calcine it at 550°C for 6 h to obtain a catalyst precursor with a NiO content of 10.6 parts by weight.

[0101] 100 g of the above catalyst precursor was put into 0.2 L of 0.18 mol / L silver nitrate aqueous solution, immersed for 1 h, dried at 110°C for 6 h, and then calcined at 600°C for 6 h to obtain catalyst A2, whose composition was: 3 parts by weight of Ag2O, 10 parts by weight of NiO and 87 parts by weight of the composite oxide carrier.

[0102] Example 10

[0103] The catalyst was prepared according to the preparation method of the Ni-Ag / Al2O3-CuO-TiO2 catalyst in Example 9, with the only difference being that the Al2O3-CuO-TiO2 composite oxide carriers B, C, and D prepared above were taken respectively, and the concentrations of the nickel nitrate solution and the silver nitrate aqueous solution were changed to prepare catalysts B2, C2, and D2 with different Ni and Ag contents.

[0104] Embodiment 11

[0105] A method for preparing a Ni-Ru / Al2O3-CuO-TiO2 catalyst.

[0106] Take 100 g of the Al2O3-CuO-TiO2 composite oxide carrier D prepared in Example 4, put it into 0.4 L of 1.0 mol / L nickel nitrate solution, soak it for 3 h, dry it at 110°C for 6 h, and then calcine it at 500°C for 4 h to obtain a catalyst precursor with a NiO content of 20.8 parts by weight.

[0107] 100 g of the above catalyst precursor was put into 0.2 L of 0.025 mol / L ruthenium nitrate aqueous solution, immersed for 1 h, dried at 110°C for 6 h, and then calcined at 500°C for 4 h to obtain catalyst D3, whose composition was: Ru content of 0.5 parts by weight, NiO content of 20 parts by weight and composite oxide carrier content of 79.5 parts by weight.

[0108] Example 12

[0109] The catalyst was prepared according to the preparation method of the Ni-Ru / Al2O3-CuO-TiO2 catalyst in Example 11, with the only difference being that the Al2O3-CuO-TiO2 composite oxide carriers A, B, and C prepared above were taken, the concentrations of the nickel nitrate solution and the ruthenium nitrate aqueous solution were changed, and catalysts A3, B3, and C3 with different Ni and Ru contents were prepared.

[0110] Embodiment 13

[0111] A method for preparing a Ni-Ag / Al2O3-CuO-TiO2 catalyst.

[0112] Take 100 g of the Al2O3-CuO-TiO2 composite oxide carrier A prepared in Example 1, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 150 min, dry it at 110°C for 6 h, and then calcine it at 500°C for 4 h to obtain a catalyst precursor with a NiO content of 10.6 parts by weight.

[0113] 100 g of the above catalyst precursor was taken, and the concentration of the silver nitrate aqueous solution was changed to prepare catalysts A4, A5, and A6 with the same carrier, the same Ni content, and different Ag contents.

[0114] Comparative Example 4

[0115] Take 100 g of the Al2O3-TiO2 composite oxide carrier G prepared in Comparative Example 1, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 1 hour, dry it at 110°C for 6 hours, and then calcine it at 550°C for 6 hours to obtain a catalyst precursor with a NiO content of 10.6 parts by weight.

[0116] 100 g of the above catalyst was taken as a precursor and put into 0.2 L of 0.18 mol / L silver nitrate aqueous solution, immersed for 1 h, dried at 110° C. for 6 h, and then calcined at 600° C. for 6 h to obtain catalyst G1, whose composition was: Ag content of 0.5 parts by weight, NiO content of 10 parts by weight and composite oxide carrier content of 89.5 parts by weight.

[0117] Comparative Example 5

[0118] Take 100 g of the Al2O3-TiO2 composite oxide carrier G prepared in Comparative Example 1, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 1 hour, dry it at 110°C for 6 hours, and then calcine it at 550°C for 6 hours to obtain a catalyst precursor with a NiO content of 10.6 parts by weight.

[0119] Take 100 g of the above catalyst as a precursor and put it into 0.2 L of a 0.15 mol / L ruthenium nitrate aqueous solution, soak it for 1 hour, dry it at 110°C for 6 hours, and then calcine it at 500°C for 4 hours to obtain catalyst G2, whose composition is: Ru content is 0.5 parts by weight, NiO content is 10 parts by weight and composite oxide carrier content is 89.5 parts by weight.

[0120] Comparative Example 6

[0121] Take 100 g of the Al2O3-CuO composite oxide support H prepared in Comparative Example 2, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 150 min, dry it at 110°C for 6 h, and then calcine it at 500°C for 4 h to obtain a catalyst precursor with a NiO content of 10.6 parts by weight.

[0122] 100 g of the above catalyst was taken as a precursor and put into 0.2 L of 0.18 mol / L silver nitrate aqueous solution, immersed for 1 h, dried at 110°C for 6 h, and then calcined at 600°C for 6 h to obtain catalyst H1, whose composition was: Ag content of 3 parts by weight, NiO content of 10 parts by weight and composite oxide carrier content of 89.5 parts by weight.

[0123] Comparative Example 7

[0124] Take 100 g of the Al2O3-CuO composite oxide support H prepared in Comparative Example 2, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 150 min, dry it at 110°C for 6 h, and then calcine it at 500°C for 4 h to obtain a catalyst precursor with a NiO content of 10.6 parts by weight.

[0125] Take 100 g of the above catalyst as a precursor and put it into 0.2 L of a 0.15 mol / L ruthenium nitrate aqueous solution, soak it for 1 hour, dry it at 110°C for 6 hours, and then calcine it at 500°C for 4 hours to obtain a catalyst H2, whose composition is: 0.5 parts by weight of Ru, 10 parts by weight of NiO and 89.5 parts by weight of the composite oxide carrier.

[0126] Comparative Example 8

[0127] Take 100 g of the γ-Al2O3 carrier of Comparative Example 3, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 150 min, dry it at 110°C for 6 h, and then calcine it at 500°C for 4 h to obtain a catalyst precursor with a NiO content of 10.6 parts by weight.

[0128] Take 100 g of the above catalyst as a precursor and put it into 0.2 L of 0.18 mol / L silver nitrate aqueous solution, soak it for 1 hour, dry it at 110°C for 6 hours, and then calcine it at 600°C for 6 hours to obtain catalyst I1, whose composition is: Ag content is 3 parts, NiO content is 10 parts and composite oxide carrier content is 89.5 parts.

[0129] Comparative Example 9

[0130] Take 100 g of the γ-Al2O3 carrier of Comparative Example 3, put it into 0.2 L of 1.0 mol / L nickel nitrate solution, soak it for 150 min, dry it at 110°C for 6 h, and then calcine it at 500°C for 4 h to obtain a catalyst precursor with a NiO content of 10.6 parts by weight.

[0131] Take 100 g of the above catalyst as a precursor and put it into 0.2 L of a 0.15 mol / L ruthenium nitrate aqueous solution, soak it for 1 hour, dry it at 110°C for 6 hours, and then calcine it at 500°C for 4 hours to obtain catalyst I2, whose composition is: Ru content is 0.5 parts by weight, NiO content is 10 parts by weight and composite oxide carrier content is 89.5 parts by weight.

[0132] According to specific examples 7 to 13 and comparative examples 4 to 9, the contents of the various components of the catalyst are shown in Table 2.

[0133] Table 2 Composition of each catalyst

[0134]

[0135] Application Examples

[0136] The catalyst used in this application example is the catalyst prepared in the examples and comparative examples, and the evaluation was carried out under the same conditions.

[0137] The reaction conditions for preparing cyclopentene from cyclopentadiene are as follows: a trickle bed hydrogenation reactor with a catalyst loading volume of 100 mL is used, the catalyst loading volume is 100 mL, the reaction pressure is 0.6 Pa, the reaction temperature is 30°C, the molar ratio of hydrogen to cyclopentadiene is 1.2:1, the volume ratio of cyclopentadiene to the diluent solvent cyclohexane is 1:5, and the feed volume space velocity (the volume ratio of the liquid raw material feed volume to the catalyst loading volume per hour) is 6.0 h -1 .

[0138] Table 3 Cyclopentadiene selective hydrogenation results

[0139]

[0140] As can be seen from Table 3, the selective hydrogenation reaction of cyclopentadiene using the catalyst provided by the present invention can produce cyclopentene with high conversion rate and high selectivity. Combined with Table 1 and Table 2, it is believed that the Al2O3-CuO-TiO2 composite oxide used in the present invention, titanium oxide and aluminum oxide are uniformly mixed and enriched on the composite oxide surface, and CuO is uniformly dispersed on the composite oxide skeleton structure. At high temperatures, Al2O3, CuO, and TiO2 form a strong interaction, so the thermal stability of the composite oxide is high, which overcomes the defect that the copper element is unstable at high temperatures. Further, the high temperature roasting of TiO2 at 700 to 1000 ° C can still maintain the active phase of anatase, ensuring the activity of the catalyst.

[0141] Any numerical value mentioned in the present invention, if there is only an interval of two units between any minimum value and any maximum value, includes all values ​​from the minimum value to the maximum value each time increasing by one unit. For example, if the amount of a component, or the value of a process variable such as temperature, pressure, time, etc. is declared to be 50-90, in this specification it means that 51-89, 52-88... and 69-71 and 70-71 are specifically listed. For non-integer values, 0.1, 0.01, 0.001 or 0.0001 can be appropriately considered as a unit. These are just some specially specified examples. In this application, in a similar manner, all possible combinations of numerical values ​​between the listed minimum and maximum values ​​are considered to have been disclosed.

[0142] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein, on the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A catalyst for the selective hydrogenation of cyclopentadiene, wherein: The catalyst comprises an Al2O3-CuO-TiO2 composite oxide carrier, a main active component Ni and an optional auxiliary active component supported thereon, wherein the auxiliary active component is selected from at least one of Ag and Ru.

2. The catalyst according to claim 1, characterized in that Based on the weight of the composite oxide support as 100 parts by weight, the content of CuO is 0.1 to 5 parts, the content of TiO2 is 5 to 25 parts, and the content of Al2O3 is 70 to 94.9 parts; preferably, based on the weight of the composite oxide support as 100 parts by weight, the content of CuO is 0.3 to 3 parts, the content of TiO2 is 9 to 20 parts, and the content of Al2O3 is 77 to 90.7 parts; more preferably, based on the weight of the composite oxide support as 100 parts by weight, the content of CuO is 1.5 to 3 parts, the content of TiO2 is 12 to 18 parts, and the content of Al2O3 is 79 to 86.5 parts.

3. The catalyst according to claim 1 or 2, characterized in that Based on the total weight of the catalyst as 100 parts by weight, the content of the main active component Ni is 5 to 25 parts in terms of NiO, preferably 10 to 20 parts, more preferably 10 to 15 parts, and most preferably 10 to 12 parts; the content of the auxiliary active component is 0 to 5 parts in terms of oxide, preferably 0.5 to 3 parts, more preferably 1 to 3 parts, and most preferably 2 to 3 parts; the content of the composite oxide is 70 to 95 parts, preferably 79.5 to 87 parts, more preferably 82 to 87 parts, and most preferably 85 to 87 parts.

4. The catalyst according to any one of claims 1 to 3, characterized in that The specific surface area of ​​the composite oxide carrier is 30 to 155 m 2 / g, preferably 55 to 85m 2 / g, more preferably 55 to 70 m 2 / g; And / or, the pore volume of the composite oxide support is 0.2 to 0.8 mL / g, preferably 0.3 to 0.4 mL / g.

5. The method for preparing the catalyst according to any one of claims 1 to 4, wherein: The preparation method comprises the following steps: S110, impregnating the Al2O3-CuO-TiO2 composite oxide support with a nickel salt solution to obtain an impregnated composite oxide support, and drying and calcining the impregnated composite oxide support to obtain a catalyst precursor; Optionally, S120, the catalyst precursor is impregnated with a salt solution of an auxiliary active component to obtain an impregnated catalyst precursor, and the impregnated catalyst precursor is dried and calcined to obtain a catalyst.

6. The preparation method according to claim 5, characterized in that: The time of the immersion treatment in steps S110 and S120 is independently 1 to 8 hours, preferably 1 to 4 hours; And / or, the drying conditions in steps S110 and S120 independently include: a drying temperature of 90-120° C.; and / or a drying time of 2-8 hours; And / or, the conditions for the calcination treatment in steps S110 and S120 independently include: a calcination temperature of 300-800° C.; and / or a calcination time of 2-10 h.

7. The preparation method according to claim 5 or 6, characterized in that: The nickel salt is selected from the group consisting of nickel sulfates, nitrates, soluble carboxylates, hypophosphites and halides; and / or, in terms of NiO, the concentration of the nickel salt solution is 1.0 to 3.0 mol / L; and / or, the salt of the co-active component is selected from nitrates, soluble carboxylates and soluble halides; And / or, the concentration of the salt solution of the co-active component is 0.01-0.3 mol / L in terms of metal oxide.

8. The preparation method according to any one of claims 5 to 7, characterized in that: The preparation method of the composite oxide carrier comprises: S210, adding a copper salt solution, a titanium salt solution and an alkaline solution to an aluminum salt solution in parallel at a temperature of 50 to 90° C., and after staying at a pH value of 5.5 to 7.0 for 15 to 20 minutes, continuing to add an alkaline solution until the pH value reaches 8 to 10, and staying for 15 to 20 minutes to obtain a precipitate; S220, washing, drying and calcining the precipitate to obtain a composite oxide support; Preferably, the aluminum salt is selected from aluminum sulfate, aluminum chloride, aluminum nitrate and organic aluminum salt, and / or the concentration of the aluminum salt aqueous solution is 0.5 to 2.5 mol / L; Preferably, the titanium salt solution is an acid solution of a soluble titanium salt selected from metatitanic acid, titanium tetrachloride and tetraethyl titanate, such as a sulfuric acid solution; and / or, the concentration of the titanium salt solution is 0.2 to 1.2 mol / L; Preferably, the copper salt is selected from copper chloride, copper sulfate and copper nitrate; and / or, the concentration of the copper salt solution is 0.1 to 0.6 mol / L; Preferably, the alkaline solution comprises an ammonium salt and an alkali solution; more preferably, the ammonium salt is selected from ammonium bicarbonate, ammonium carbonate and an organic ammonium salt, and / or the concentration of the ammonium salt in the alkaline solution is 0.1 to 0.3 mol / L; Preferably, the drying conditions in step S220 include: a drying temperature of 100 to 150° C. and a drying time of 4 to 12 hours; Preferably, the calcination conditions in step S220 include: a calcination temperature of 500 to 1100° C. and a calcination time of 4 to 12 hours.

9. Use of the catalyst according to any one of claims 1 to 4 in the selective hydrogenation of cyclopentadiene to prepare cyclopentene.

10. A method for preparing cyclopentene by selective hydrogenation of cyclopentadiene, wherein: The method comprises: Mixing cyclopentadiene and a diluent solvent, and subjecting the cyclopentadiene to a hydrogenation reaction with hydrogen in the presence of a catalyst according to any one of claims 1 to 4 to produce cyclopentene; Preferably, the dilution solvent is selected from n-heptane, isooctane, cyclohexane, preferably selected from n-heptane and isooctane; Preferably, the conditions of the hydrogenation reaction include: reaction temperature of 20-70°C, reaction pressure of 0.1-1.5 MPa, feed volume space velocity of 0.5-15 h -1 The molar ratio of cyclopentadiene to hydrogen is 1:(1.0-3.0), and the volume ratio of cyclopentadiene to the dilution solvent is 1:(0.1-20).

Images