Noble metal catalyst for preparing dihydrodicyclopentadiene, preparation method of noble metal catalyst and method for preparing dihydrodicyclopentadiene

Abstract

The invention relates to a noble metal catalyst for preparing dihydrodicyclopentadiene, a preparation method thereof and a method for preparing dihydrodicyclopentadiene, the noble metal catalyst contains a carrier and an active component, the carrier is one or more of titanium dioxide, cerium dioxide, silicon dioxide, aluminum oxide and activated carbon, and the active component is one or more of titanium dioxide, cerium dioxide, silicon dioxide, aluminum oxide and activated carbon. The active component contains one or more of palladium and platinum; on the basis of the dry basis weight of the noble metal catalyst, the content of the active component is more than 0.3 wt%; the particle size range of the active component is D + / -a, D ranges from 5 nm to 13 nm, and a ranges from 1 nm to 4.2 nm. The catalyst provided by the invention has relatively high reaction activity, and has relatively high selectivity on dihydrodicyclopentadiene.

Description

Technical Field

[0001] The present application relates to a noble metal catalyst for preparing dihydrodicyclopentadiene and a preparation method thereof, and a method for preparing dihydrodicyclopentadiene. Background Art

[0002] With the increasing scale of ethylene and petroleum catalytic cracking units, C5 fraction resources are becoming increasingly abundant. As the main component of C5 fraction, dicyclopentadiene (DCPD) is of great significance to achieve its efficient utilization. The DCPD molecule is a cyclic hydrocarbon containing two unsaturated bonds. Its semi-hydrogenated product, endo-dihydrodicyclopentadiene (Endo-DHDCPD), can be synthesized through the Diels-Alder reaction to prepare other chemicals, such as tetrahydrotricyclopentadiene high-density fuel; it can also be further hydrogenated to obtain endo-tetrahydrodicyclopentadiene (Endo-THDCPD, the main component of JP-10 fuel), which is an important fine chemical, pharmaceutical intermediate, and material intermediate.

[0003] At present, the Raney Ni catalyst that has been put into industrial application has high DCPD hydrogenation activity, but the catalyst is relatively active, flammable and explosive, and difficult to store. Therefore, supported catalysts with high activity have attracted widespread attention.

[0004] CN 111662150 A discloses a method for preparing bridged dihydrodicyclopentadiene by hydrogenating dicyclopentadiene, wherein dicyclopentadiene is shallowly hydrogenated to bridged dihydrodicyclopentadiene by using a hydrogen supplying agent in the presence of a hydrogenation catalyst. Summary of the invention

[0005] The purpose of the present invention is to provide a noble metal catalyst for preparing dihydrodicyclopentadiene and a preparation method thereof, and a method for preparing dihydrodicyclopentadiene. The noble metal catalyst of the present invention has high reaction activity and high selectivity for dihydrodicyclopentadiene.

[0006] In order to achieve the above-mentioned object, the present invention provides a precious metal catalyst for preparing dihydrodicyclopentadiene, wherein the precious metal catalyst contains a carrier and an active component, wherein the carrier is one or more of titanium dioxide, cerium dioxide, silicon dioxide, aluminum oxide and activated carbon, and the active component contains one or more of palladium and platinum; based on the dry weight of the precious metal catalyst, the content of the active component is more than 0.3 weight percent; the particle size range of the active component is D±a, wherein D is 5-13 nm and a is 1-4.2 nm.

[0007] Optionally, the carrier is titanium dioxide, the active component is palladium, the content of the active component is 0.3-2% by weight, and the active component is calculated as a metal element.

[0008] Optionally, D is 5-10 nm and a is 1-4 nm.

[0009] The second aspect of the present invention provides a method for preparing the noble metal catalyst provided by the first aspect of the present invention, the method comprising: mixing and grinding a noble metal precursor and a carrier, and heat-treating the obtained mixture.

[0010] Optionally, the noble metal precursor is selected from one or more of an organic palladium salt, an inorganic palladium salt, an organic platinum salt, and an inorganic platinum salt;

[0011] Preferably, the noble metal precursor is selected from one or more of palladium acetylacetonate, palladium acetate, palladium chloride, palladium nitrate, platinum acetylacetonate, platinum acetate, platinum chloride and platinum nitrate.

[0012] Optionally, the mixing and grinding time is 1-30 min, preferably 5-20 min.

[0013] Optionally, the heat treatment conditions include: a temperature of 350-1000° C., a time of 1.5-5 h, and an atmosphere of one or more of air, nitrogen, hydrogen, and a hydrogen-nitrogen mixture.

[0014] The third aspect of the present invention provides a method for preparing dihydrodicyclopentadiene, which comprises: in the presence of a noble metal catalyst and a solvent, subjecting dicyclopentadiene to a hydrogenation reaction to prepare dihydrodicyclopentadiene; the noble metal catalyst is the noble metal catalyst provided in the first aspect of the present invention.

[0015] Optionally, the conditions for the hydrogenation reaction include: reaction temperature of 10-30° C., hydrogen pressure of 2-8 MPa, reaction time of 1-24 h, and stirring speed of 400-1000 r / min.

[0016] Optionally, the weight ratio of the noble metal catalyst to dicyclopentadiene is 1:(1-20); the weight ratio of the solvent to the dicyclopentadiene is 1:(10-30); and the solvent is selected from one or more of methylcyclohexane, benzene, toluene and cyclohexane.

[0017] Through the above technical scheme, the active component nanoparticles of the noble metal catalyst of the present invention are loaded on the carrier, and the catalyst has excellent catalytic hydrogenation reaction and selectivity for dihydrodicyclopentadiene.

[0018] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 It is the XRD spectrum of the noble metal catalyst prepared in Example 1 of the present invention.

[0021] Figure 2 This is a TEM photograph of the precious metal catalyst prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0022] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0023] The first aspect of the present invention provides a precious metal catalyst for preparing dihydrodicyclopentadiene, wherein the precious metal catalyst contains a carrier and an active component, wherein the carrier is one or more of titanium dioxide, cerium dioxide, silicon dioxide, aluminum oxide and activated carbon, and the active component contains one or more of palladium and platinum; based on the dry weight of the precious metal catalyst, the content of the active component is greater than 0.3% by weight; the particle size range of the active component is D±a, wherein D is 5-13nm and a is 1-4.2nm.

[0024] The noble metal catalyst of the invention has active components with specific nanometer sizes, and the particle size distribution range of the active components is narrow and the aggregation is small. The noble metal catalyst has relatively good reaction activity and selectivity for dihydrodicyclopentadiene.

[0025] In a specific embodiment, the carrier is titanium dioxide, the active component is palladium, the content of the active component is 0.3-2% by weight, preferably 0.3-1% by weight, and the active component is calculated as a metal element.

[0026] According to the present invention, the active component in the precious metal catalyst of the present invention is loaded on the carrier as particles of a specific nanometer size, and the particle size distribution range of the active component is narrow. In a specific embodiment, the particle size range of the active component is D±a, wherein D is 5-10nm and a is 1-4nm. In the present invention, a TEM analysis is performed on the precious metal catalyst by a transmission electron microscope, and 150 active component particles are randomly selected from the TEM photo thereof, and the distances corresponding to the two points with the largest distance on the 150 active component particles are measured respectively, and the average value of the distance is calculated to obtain D, and the standard deviation of the distance is calculated to obtain a, and the particle size range of the active component is expressed as D±a.

[0027] The second aspect of the present invention provides a method for preparing the noble metal catalyst provided by the first aspect of the present invention, the method comprising: mixing and grinding the noble metal precursor and the carrier, and heat-treating the obtained mixture.

[0028] The present invention adopts the method of mixing and grinding the precious metal precursor and the carrier and then heat treating for the first time to prepare the precious metal catalyst, and the method is simple and easy to operate. And the inventor of the present invention has found through research that the traditional impregnation method for loading active components on the carrier may cause the precious metal active components to precipitate due to uneven stirring of the impregnation liquid during the impregnation process, resulting in uneven concentration of the impregnation liquid, so that the particle size difference of the active components on the catalyst obtained by impregnation is relatively large, while the contact between the precious metal precursor and the carrier is more fully and uniform during sufficient mechanical grinding. The catalyst prepared by the method of the present invention has excellent hydrogenation performance, and the particle size distribution range of the active component is narrow, so that it has good selectivity for dihydrodicyclopentadiene.

[0029] In a specific embodiment, the noble metal precursor is selected from one or more of an organic palladium salt, an inorganic palladium salt, an organic platinum salt, and an inorganic platinum salt; preferably, the noble metal precursor is selected from one or more of palladium acetylacetonate, palladium acetate, palladium chloride, palladium nitrate, platinum acetylacetonate, platinum acetate, platinum chloride, and platinum nitrate. More preferably, the noble metal precursor is selected from one or more of palladium acetylacetonate, palladium acetate, platinum acetylacetonate, and platinum acetate. The metal precursor used in the preparation of the noble metal catalyst of the present invention is an organic metal salt precursor, which is decomposed by the heat treatment step of the preparation process, leaving only the metal load on the carrier, and will not introduce impurities such as chlorine in the inorganic metal salt, so that the prepared noble metal catalyst has better reaction activity and selectivity for dihydrodicyclopentadiene.

[0030] According to the present invention, the time of mixing and grinding can vary within a wide range. In a preferred embodiment, the time of mixing and grinding is 1-30 min, preferably 3-20 min, and more preferably 5-20 min. Grinding can be performed using equipment well known to those skilled in the art, such as a mortar.

[0031] In a specific embodiment, the heat treatment conditions include: a temperature of 350-1000°C, a time of 1.5-5h, and an atmosphere of one or more of air, nitrogen, hydrogen, and a hydrogen-nitrogen mixture; preferably, the temperature is 400-600°C, and the time is 1.5-4h. The heat treatment can be carried out in equipment well known to those skilled in the art, such as a muffle furnace, a tubular furnace, etc., and the present invention does not specifically limit this.

[0032] In a specific embodiment, the product obtained by heat treatment is subjected to reduction treatment in a hydrogen atmosphere to improve the conversion rate of the raw material when the noble metal catalyst is used to prepare dihydrodicyclopentadiene. The reduction conditions include: temperature of 100-300° C. and time of 1-3 hours.

[0033] The third aspect of the present invention provides a method for preparing dihydrodicyclopentadiene, the method comprising: in the presence of a noble metal catalyst and a solvent, subjecting dicyclopentadiene to a hydrogenation reaction to prepare dihydrodicyclopentadiene; the noble metal catalyst is the noble metal catalyst provided by the first aspect of the present invention. The method of the present invention has a high selectivity for dihydrodicyclopentadiene.

[0034] In a specific embodiment of the present invention, the conditions of the hydrogenation reaction include: reaction temperature of 10-30°C, hydrogen pressure of 2-8MPa, reaction time of 1-24h, stirring speed of 400-1000r / min; preferably, the reaction temperature is 10-20°C, hydrogen pressure is 3-5MPa, reaction time is 1-10h, and stirring speed is 450-800r / min.

[0035] According to the present invention, the weight ratio of the noble metal catalyst to the amount of dicyclopentadiene can vary within a wide range. In a specific embodiment of the present invention, the weight ratio of the noble metal catalyst to the amount of dicyclopentadiene is 1:(1-20), preferably 1:(1-10); the weight ratio of the solvent to the amount of dicyclopentadiene is 1:(10-30), preferably 1:(10-20); the solvent is selected from one or more of methylcyclohexane, benzene, toluene and cyclohexane. Under the above conditions, the selectivity for dihydrodicyclopentadiene can be further improved.

[0036] The present invention is further described below by way of examples, but the present invention is not limited thereto.

[0037] Unless otherwise specified, the raw materials used in the examples and comparative examples of the present invention are commercially available.

[0038] Examples 1-10 are examples of preparing catalysts, and Comparative Example 1 is a comparative example of preparing catalysts; Examples 11-21 are examples of preparing dihydrodicyclopentadiene, and Comparative Example 2 is an example of preparing dihydrodicyclopentadiene.

[0039] Example 1

[0040] Palladium acetylacetonate and titanium dioxide (P25) were mixed and ground for 20 minutes, which was recorded as mixture A, in which the mass fraction of Pd was 0.3 wt %. Mixture A was placed in a muffle furnace for calcination in air at a heat treatment temperature of 500° C. for 2 h to obtain a noble metal catalyst A loaded with Pd.

[0041] The composition of the noble metal catalyst and the particle size of the active component are shown in Table 1, and the same below. The XRD spectrum of the noble metal catalyst is shown in Figure 1 As shown in the TEM photo Figure 2 As shown, the XRD spectrum only has the diffraction peak of titanium dioxide (P25), indicating that the active metal particles in the catalyst have no obvious aggregation.

[0042] Example 2

[0043] The noble metal catalyst B was prepared by the same method as in Example 1, except that the carrier was cerium dioxide, and the catalyst was calcined in a muffle furnace and then reduced with hydrogen in a tubular furnace at 200° C. for 1 h.

[0044] Example 3

[0045] The noble metal catalyst C was prepared by the same method as in Example 1, except that the heat treatment temperature was 300° C., the heat treatment time was 1 h, and the heat treatment atmosphere was air.

[0046] Example 4

[0047] The noble metal catalyst D was prepared by the same method as in Example 1, except that the grinding time was 3 min.

[0048] Example 5

[0049] The noble metal catalyst E was prepared in the same manner as in Example 1, except that palladium acetylacetonate and titanium dioxide (P25) were mixed and ground for 20 minutes, referred to as mixture B, in which the mass fraction of Pd was 2.3 wt %.

[0050] Example 6

[0051] The noble metal catalyst F was prepared by the same method as in Example 1, except that the carrier was silicon dioxide.

[0052] Example 7

[0053] The noble metal catalyst G was prepared by the same method as in Example 1, except that the carrier was γ-Al2O3.

[0054] Example 8

[0055] The noble metal catalyst H was prepared by the same method as in Example 1, except that the carrier was silicon dioxide, and the catalyst was calcined in a muffle furnace and then reduced with hydrogen in a tubular furnace at 200° C. for 1 h.

[0056] Example 9

[0057] The noble metal catalyst I was prepared by the same method as in Example 1, except that the carrier was γ-Al2O3 and the catalyst was calcined in a muffle furnace and then reduced with hydrogen in a tubular furnace at 200°C for 1 h.

[0058] Example 10

[0059] The noble metal catalyst J was prepared in the same manner as in Example 1, except that the catalyst was calcined in a muffle furnace and then reduced with hydrogen in a tubular furnace at 200° C. for 1 h.

[0060] Comparative Example 1

[0061] The Pd / TiO2 catalyst DA was prepared by an impregnation method, wherein the mass fraction of Pd was 0.3 wt %. The specific steps were: an equal volume of palladium nitrate solution was impregnated into titanium dioxide, followed by drying and calcining in air at 500° C. for 3 h.

[0062] Examples 11-20

[0063] The precious metal catalysts prepared in Examples 1-10 were respectively used in high-pressure reactors for catalytic hydrogenation of dicyclopentadiene. The solvent was methylcyclohexane, and the mass fraction of dicyclopentadiene was 5%. The mass ratio of the precious metal catalyst to dicyclopentadiene was 1:10. The reaction temperature was 15°C, the hydrogen pressure was 3 MPa, the reaction time was 1 h, and the stirring speed was 450 r / min.

[0064] Embodiment 21

[0065] The catalytic hydrogenation reaction of dicyclopentadiene was carried out in the same manner as in Example 11, except that the reaction temperature was 35° C., the hydrogen pressure was 6 MPa, the reaction time was 12 h, and the stirring speed was 400 r / min.

[0066] Comparative Example 2

[0067] The precious metal catalysts prepared in Comparative Example 1 were used to carry out catalytic hydrogenation of dicyclopentadiene in high-pressure reactors. The solvent was methylcyclohexane, and the mass fraction of dicyclopentadiene was 5%. The mass ratio of the precious metal catalyst to dicyclopentadiene was 1:10. The reaction temperature was room temperature (about 15°C), the pressure was 3MPa, the reaction time was 1h, and the stirring speed was 450r / min.

[0068] Table 1

[0069]

[0070] Table 2

[0071]

[0072]

[0073] It can be seen from the above that the noble metal catalyst of the present invention has a relatively good hydrogenation reaction activity, and when it is used for preparing dihydrodicyclopentadiene from dicyclopentadiene, it has a relatively high selectivity for dihydrodicyclopentadiene.

[0074] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0075] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0076] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A noble metal catalyst for preparing dihydrodicyclopentadiene, the noble metal catalyst comprising a carrier and an active component, the carrier being one or more of titanium dioxide, cerium dioxide, silicon dioxide, aluminum oxide and activated carbon, the active component comprising one or more of palladium and platinum; the content of the active component is 0.3 wt% or more based on the dry weight of the noble metal catalyst; the particle size range of the active component is D±a, wherein, D is 5-13nm, a is 1-4.2nm.

2. The noble metal catalyst according to claim 1, wherein The carrier is titanium dioxide, the active component is palladium, the content of the active component is 0.3-2% by weight, and the active component is calculated as a metal element.

3. The noble metal catalyst according to claim 1, wherein D is 5-10nm, a is 1-4nm.

4. A method for preparing the noble metal catalyst according to any one of claims 1 to 3, the method comprising: The noble metal precursor and the carrier are mixed and ground, and the obtained mixture is heat-treated.

5. The method according to claim 4, wherein: The noble metal precursor is selected from one or more of an organic palladium salt, an inorganic palladium salt, an organic platinum salt, and an inorganic platinum salt; Preferably, the noble metal precursor is selected from one or more of palladium acetylacetonate, palladium acetate, palladium chloride, palladium nitrate, platinum acetylacetonate, platinum acetate, platinum chloride and platinum nitrate.

6. The method according to claim 4, wherein: The mixing and grinding time is 1-30 min, preferably 5-20 min.

7. The method according to claim 4, wherein: The heat treatment conditions include: a temperature of 350-1000° C., a time of 1.5-5 hours, and an atmosphere of one or more of air, nitrogen, hydrogen, and a hydrogen-nitrogen mixture.

8. A method for preparing dihydrodicyclopentadiene, the method comprising: In the presence of a noble metal catalyst and a solvent, dicyclopentadiene is subjected to a hydrogenation reaction to prepare dihydrodicyclopentadiene; The noble metal catalyst is the noble metal catalyst according to any one of claims 1 to 3.

9. The method according to claim 8, wherein: The conditions of the hydrogenation reaction include: reaction temperature of 10-30° C., hydrogen pressure of 2-8 MPa, reaction time of 1-24 h, and stirring speed of 400-1000 r / min.

10. The method according to claim 8, wherein: The weight ratio of the noble metal catalyst to dicyclopentadiene is 1:(1-20); the weight ratio of the solvent to dicyclopentadiene is 1:(10-30); the solvent is selected from one or more of methylcyclohexane, benzene, toluene and cyclohexane.

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