Polycyclic aromatic hydrocarbon hydrogenation saturation catalyst as well as preparation method and application thereof

Abstract

The invention provides a polycyclic aromatic hydrocarbon hydrogenation saturation catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, mixing a structure-directing agent, a silicon source and a solvent, stirring, and washing to obtain a solid intermediate product; s2, the solid intermediate product and an aluminum salt solution are mixed and dissolved, ammonia water is added into the formed solution to adjust the pH value, and a reaction is conducted under the stirring condition; s3, mixing the reaction product obtained in the step S2 with a USY molecular sieve, carrying out a hydrothermal reaction, filtering, and washing to obtain a hydrothermal reaction product; s4, performing first drying and first roasting on the hydrothermal reaction product to obtain an Al-SBA15 / USY composite molecular sieve; and step S5, loading a metal active component on the Al-SBA15 / USY composite molecular sieve to obtain the polycyclic aromatic hydrocarbon hydrogenation saturation catalyst. The catalyst has a micro-mesoporous pore channel structure and has a remarkable catalytic effect in a polycyclic aromatic hydrocarbon hydrogenation saturation reaction.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of hydrogenation catalysis, in particular to a condensed aromatic hydrocarbon hydrogenation saturation catalyst, a preparation method and application thereof. BACKGROUND

[0002] With the development of modern coal chemical industry and coking industry in China, a large amount of by-products, i.e. coal tar, will be produced in the processing. Direct combustion of coal tar will pollute the environment, and its composition is complex, rich in condensed aromatic hydrocarbons. The components of coal tar can be preliminarily separated by cutting and fractionation. A large amount of condensed aromatic hydrocarbons are contained in anthracene oil obtained by distillation at a temperature of 280-360℃, and the total aromatic hydrocarbon content is more than 90%. Condensed aromatic hydrocarbons are widely used in fuel, medicine and alloy, etc. Further processing of condensed aromatic hydrocarbons into saturated aromatic hydrocarbons has a compact molecular structure and a robust ring strain, and is widely used. At the same time, because of its high volumetric energy density and the ability to improve the stability of fuel, it becomes an ideal component of jet fuel. Therefore, the research on hydrogenation saturation reaction and the preparation of hydrogenation saturation catalyst are of great significance to coal tar chemical industry.

[0003] Efficient utilization and deep removal of condensed aromatic hydrocarbons are usually considered as effective means for hydrogenation saturation of condensed aromatic hydrocarbons, and an important factor for realizing this process is to develop and utilize high-activity supported catalysts. The supported noble metal of the supported catalyst has good hydrogenation activity, so in order to make the performance of the catalyst more superior, the carrier should be started. The carrier plays a very important role in the whole catalyst, which not only provides a place for the metal active component, but also participates in the reaction due to its unique properties. The pore structure and the acidity and alkalinity of the carrier itself are two important indicators for evaluating the carrier. The unique pore structure and the appropriate pore size are the key to the free diffusion of reactants and products, and the acidity of the carrier itself also affects the reaction. Strong acidity can accelerate the cracking of products, and weak acidity will not promote the reaction. Therefore, microporous molecular sieves have certain limitations in the hydrogenation saturation of macromolecules, and too strong acidity will cause secondary cracking and decrease selectivity.

[0004] Patent CN104117386A reports a condensed aromatic hydrocarbon hydrogenation catalyst loaded with 0.1%-2% of platinum, palladium, iridium and other noble metals on a Beta molecular sieve. Under the conditions of space velocity of 0.5-10h -1 , reaction temperature of 260-300℃ and reaction pressure of 6MPa, the conversion rate of naphthalene is 100%, and the ring-opening selectivity is more than 37%. Corma et al. compared the changes of catalytic hydrogenation reaction performance of active metal Pt supported on different carriers (γ-Al2O3 / USY / MCM-41) on naphthalene. It is found that the higher specific surface area and regular pore structure of the molecular sieve make the dispersion degree of the active metal Pt higher, the particle size smaller, and the surface of the molecular sieve has more active sites, which is beneficial to the hydrogenation of naphthalene. The acid sites promote the formation of electron-deficient Pt clusters, thereby enhancing the hydrogenation activity of the catalyst.

[0005] Although the catalysts loaded with noble metals show better hydrogenation activity, there are still some difficulties in hydrogenation saturation of polycyclic aromatic hydrocarbons to saturated aromatic hydrocarbons, and the hydrogenation saturation is poor. If the loading amount of noble metals is increased to continue the hydrogenation saturation, there are disadvantages such as high cost, high processing cost and difficult industrial production. If non-noble metals are used to increase the loading amount to solve this problem, there are still disadvantages such as limited loading amount and poor carrier bearing capacity. SUMMARY

[0006] The main purpose of the present application is to provide a polycyclic aromatic hydrocarbon hydrogenation saturation catalyst and a preparation method and application thereof, so as to solve the problem of poor catalytic effect of the catalyst in the prior art in polycyclic aromatic hydrocarbon hydrogenation saturation.

[0007] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a preparation method of a polycyclic aromatic hydrocarbon hydrogenation saturation catalyst is provided, comprising the following steps: step S1, mixing a structure directing agent, a silicon source and a solvent, stirring, washing to obtain a solid intermediate product; step S2, mixing and dissolving the solid intermediate product and an aluminum salt solution, adding ammonia water to adjust the pH value in the formed solution, and reacting under stirring conditions; step S3, mixing the reaction product of step S2 with USY molecular sieve, carrying out hydrothermal reaction, filtering, washing to obtain a hydrothermal reaction product; step S4, carrying out first drying and first calcination on the hydrothermal reaction product to obtain an Al-SBA15 / USY composite molecular sieve; and step S5, loading the Al-SBA15 / USY composite molecular sieve with a metal active component to obtain a polycyclic aromatic hydrocarbon hydrogenation saturation catalyst.

[0008] Further, the structure directing agent comprises any one or more of triblock copolymers EO 20 PO 70 EO 20 , EO 106 PO 70 EO 106 ;

[0009] The silicon source comprises any one or more of tetraethyl orthosilicate, tetra-methyl orthosilicate and silica sol;

[0010] The mass ratio of the structure directing agent to the silicon source is 0.5-1.0;

[0011] The solvent in step S1 comprises hydrochloric acid and acetic acid, and preferably, the concentration of the hydrochloric acid is 0.5-2.5 mol / L;

[0012] The duration of the stirring in step S1 is 20-28 h.

[0013] Further, the aluminum salt is any one or more of aluminum nitrate nonahydrate, aluminum chloride hexahydrate and aluminum isopropoxide;

[0014] In step S2, the mass ratio of the solid intermediate product to the aluminum salt is 0.2-0.8;

[0015] In step S2, ammonia is added to adjust the pH value to 1-4;

[0016] In step S2, the reaction time is 2-5h and the reaction temperature is 25-40℃.

[0017] Further, the silicon-aluminum ratio of the USY molecular sieve is 13-115.

[0018] Further, the temperature of the hydrothermal reaction is 120-180℃ and the time is 20-30h;

[0019] Preferably, the hydrothermal reaction is carried out under static state.

[0020] Further, in step S4, the first drying is carried out at a temperature increasing rate of 3-5℃ / min, the temperature is increased to 50-70℃, and the temperature is kept for 12-24h;

[0021] In step S4, the first calcination is carried out at a temperature of 500-600℃ for 1.5-3.5h, and preferably, the temperature increasing rate during the first calcination is 1-3℃ / min;

[0022] In step S4, the mass ratio of the USY molecular sieve to the Al-SBA15 molecular sieve in the Al-SBA15 / USY composite molecular sieve is 1:2-1:10.

[0023] Further, the metal active component is any one or more of Pt, Pb and Ru; and preferably, the metal active component is Pt.

[0024] The mass fraction of the metal active component in the condensed aromatic hydrocarbon hydrogenation saturation catalyst is 0.5wt%-1.5wt%;

[0025] In step S5, the method for loading the metal active component is the equal-volume impregnation method.

[0026] Further, step S5 comprises: mixing the Al-SBA15 / USY composite molecular sieve with a metal active component precursor solution, stirring at room temperature, carrying out second drying, second calcination and reduction calcination to obtain the condensed aromatic hydrocarbon hydrogenation saturation catalyst;

[0027] Preferably, the second drying is carried out at a temperature increasing rate of 3-5℃ / min to a drying temperature, and the second drying temperature is 80-120℃.

[0028] Preferably, the second calcination is performed at a rate of 1-3℃ / min to the calcination temperature, the calcination temperature of the second calcination is 500-600℃, and the holding time at the calcination temperature is 1.5h-3.0h; preferably, the second calcination is performed in a muffle furnace.

[0029] Preferably, the reduction calcination is performed at a temperature of 500-600℃ for 3-5h.

[0030] In order to achieve the above-mentioned purpose, according to one aspect of the present application, there is provided a condensed ring aromatic hydrocarbon hydrogenation saturation catalyst prepared by any one of the above-mentioned preparation methods of the condensed ring aromatic hydrocarbon hydrogenation saturation catalyst.

[0031] According to another aspect of the present application, there is provided an application of the above-mentioned condensed ring aromatic hydrocarbon hydrogenation saturation catalyst in a condensed ring aromatic hydrocarbon hydrogenation saturation reaction.

[0032] By using the technical solution of the present application, the catalyst prepared by the method has a micro-mesoporous pore structure, which can make the reaction and the product freely diffuse, and meanwhile, the inside of the composite catalyst uses a USY microporous molecular sieve with strong acidity, and the outside uses an Al-SBA15 mesoporous molecular sieve with weak acidity, and the two are compounded to prepare a catalyst with uniform pore size and neutralized acidity, which has a better synergistic and complementary effect, and plays a significant role in the condensed ring aromatic hydrocarbon hydrogenation saturation. BRIEF DESCRIPTION OF DRAWINGS

[0033] The drawings accompanying the specification of the present application form a part thereof, serve to provide further understanding of the present application, and together with the description of the exemplary embodiments of the present application and the explanation thereof serve to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0034] Figure 1 A scanning electron microscope (SEM) image of the catalyst prepared according to Example 1 of the present application is shown;

[0035] Figure 2 A curve showing the change of the product yield with time in the anthracene saturation hydrogenation reaction of the catalyst prepared according to Example 2 of the present application is shown. DETAILED DESCRIPTION

[0036] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0037] As analyzed in the background art of the present application, there is a problem of poor catalytic effect of the catalyst in the condensed ring aromatic hydrocarbon hydrogenation saturation in the prior art. In order to solve this problem, the present application provides a condensed ring aromatic hydrocarbon hydrogenation saturation catalyst and a preparation method and application thereof.

[0038] According to an exemplary embodiment of the present application, a preparation method of a condensed ring aromatic hydro-saturation catalyst is provided, which comprises the following steps: step S1, mixing a structure directing agent, a silicon source and a solvent, stirring, washing to obtain a solid intermediate product; step S2, mixing and dissolving the solid intermediate product and an aluminum salt solution, adding ammonia water to the formed solution to adjust the pH value, and performing a reaction under stirring; step S3, mixing the reaction product of step S2 with a USY molecular sieve, performing a hydrothermal reaction, filtering, and washing to obtain a hydrothermal reaction product; step S4, performing first drying and first calcination on the hydrothermal reaction product to obtain an Al-SBA15 / USY composite molecular sieve; and step S5, loading a metal active component on the Al-SBA15 / USY composite molecular sieve to obtain the condensed ring aromatic hydro-saturation catalyst.

[0039] The preparation method of the present application adjusts the pore structure and the acid amount of the condensed ring aromatic hydro-saturation catalyst carrier, and the prepared condensed ring aromatic hydro-saturation catalyst has a micro-mesopore pore structure, which can enable the free diffusion of the reaction and the product. Meanwhile, the internal part of the composite catalyst uses a USY microporous molecular sieve with strong acidity, and the external part uses an Al-SBA15 mesoporous molecular sieve with weak acidity. The combination of the two can not only have a uniform pore size, but also neutralize the acidity to have a better synergistic and complementary effect, and has a high activity for the condensed ring aromatic hydro-saturation reaction.

[0040] In some embodiments of the present application, the structure directing agent comprises any one or more of the following: a triblock copolymer EO 20 PO 70 EO 20 , EO 106 PO 70 EO 106 The selection of the above structure directing agent is conducive to the formation of a uniform pore structure and the improvement of the catalytic effect of the catalyst on the condensed ring aromatic hydro-saturation reaction.

[0041] The silicon source can be selected in the prior art. In some embodiments of the present application, the silicon source comprises any one or more of the following: tetraethyl orthosilicate, tetramethyl orthosilicate, and silica sol, but is not limited to the above.

[0042] In some embodiments of the present application, the mass ratio of the structure directing agent to the silicon source is 0.5-1.0, so that the catalyst has a suitable pore and specific surface area, and the catalytic activity is improved.

[0043] In some embodiments of the present application, the solvent in step S1 comprises hydrochloric acid and acetic acid. Preferably, the concentration of the hydrochloric acid is 0.5-2.5 mol / L.

[0044] In some embodiments of the present application, the structure-directing agent is dissolved in hydrochloric acid and glacial acetic acid under the condition of a water bath at 25-40℃, and the silicon source is added for stirring. Preferably, the duration of stirring is 20-28h. The obtained product is filtered and washed to obtain the above-mentioned solid intermediate product. Understandably, the washing can be performed with water (such as ultrapure water, deionized water, etc.).

[0045] In the above-mentioned step S2, the solid intermediate product and the aluminum salt solution are mixed and dissolved to form a solution, and ammonia is added to adjust the pH value, and the reaction is performed under stirring. The type of aluminum salt in the aluminum salt solution can be selected in the prior art. In some embodiments of the present application, the aluminum salt is any one or more of aluminum nitrate nonahydrate, aluminum chloride hexahydrate, and aluminum isopropoxide.

[0046] In some embodiments of the present application, in step S2, the mass ratio of the solid intermediate product to the aluminum salt is 0.2-0.8.

[0047] In some embodiments of the present application, in the above-mentioned step S2, the ammonia is added to adjust the pH value to 1-4, which can be specifically 1, 1.5, 2, 2.5, 3, 3.5, 4, or other values in the above range.

[0048] In the above-mentioned step S2, after the pH value of the solution is adjusted to the above range by adding ammonia, the system is continuously stirred for reaction. Preferably, the reaction time is 2-5h, and the reaction temperature is 25-40℃.

[0049] In the above-mentioned step S3, the reaction product of step S2 is mixed with USY molecular sieve for hydrothermal reaction, filtration, and washing to obtain a hydrothermal reaction product. The USY molecular sieve can be selected in the prior art, such as a commercially available product.

[0050] In some embodiments of the present application, the silicon-aluminum ratio of the USY molecular sieve used in step S3 is 13-115, which is helpful to further improve the catalytic activity of the prepared catalyst in the hydrogenation saturation reaction of condensed ring aromatic hydrocarbons. Specifically, the silicon-aluminum ratio of the USY molecular sieve can be 13, 30, 70, 115, or other values in the above range.

[0051] In some embodiments of the present application, the temperature of the hydrothermal reaction is 120-180℃, and the time is 20-30h. Specifically, the temperature of the hydrothermal reaction can be 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, etc., and the time of the hydrothermal reaction can be 20h, 22h, 24h, 26h, 28h, 30h, etc. Preferably, the hydrothermal reaction is performed under static conditions, i.e., without stirring.

[0052] In some embodiments of the present application, the hydrothermal reaction is carried out in a stainless steel synthesis kettle, and the inner lining of the stainless steel synthesis kettle is a polytetrafluoroethylene lining, which has good high-temperature resistance and corrosion resistance and does not adversely affect the reaction.

[0053] After the hydrothermal reaction is completed, the solid product is collected by filtration and washed with deionized water to obtain a hydrothermal reaction product.

[0054] In step S4, the hydrothermal product is subjected to first drying and first calcination to obtain an Al-SBA15 / USY composite molecular sieve.

[0055] In some embodiments of the present application, in step S4, the first drying has a temperature increasing rate of 3-5℃ / min, and the temperature is increased to 50-70℃ and maintained for 12-24h.

[0056] In some embodiments of the present application, in step S4, the first calcination has a temperature of 500-600℃ and a holding time of 1.5-3.5h, and preferably, the temperature increasing rate during the first calcination is 1-3℃ / min.

[0057] In some embodiments of the present application, the hydrothermal reaction product is heated to 50-70℃ at a temperature increasing rate of 3-5℃ / min in an oven for 12-24h, and then heated to 500-600℃ at a temperature increasing rate of 1-3℃ / min in a muffle furnace for 1.5-3.5h to obtain an Al-SBA15 / USY composite molecular sieve white powder.

[0058] In some embodiments of the present application, the Al-SBA15 / USY composite molecular sieve prepared in step S4 has a mass ratio of USY molecular sieve to Al-SBA15 molecular sieve of 1:2-1:10, and specifically, the mass ratio can be 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10.

[0059] In step S5, the Al-SBA15 / USY composite molecular sieve is loaded with a metal active component to obtain a condensed aromatic hydrocarbon hydrogenation saturation catalyst.

[0060] In some embodiments of the present application, the metal active component is any one or more of Pt, Pb, and Ru, and preferably, the metal active component is Pt, which has a better catalytic effect on the condensed aromatic hydrocarbon hydrogenation saturation reaction.

[0061] In some embodiments of the present application, the mass fraction of the metal active component in the condensed aromatic hydrocarbon hydrogenation saturation catalyst is 0.5wt%-1.5wt%.

[0062] In some embodiments of the present application, the method for loading the metal active component in step S5 is an equal-volume impregnation method, which is relatively simple and the metal active component is uniformly distributed in the molecular sieve.

[0063] In some embodiments of the present application, step S5 comprises mixing the Al-SBA15 / USY composite molecular sieve with a metal active component precursor solution, stirring at room temperature, performing second drying, second calcination and reduction calcination to obtain the polycyclic aromatic hydrocarbon hydrogenation saturation catalyst. After mixing the Al-SBA15 / USY composite molecular sieve with the metal active component precursor solution, stirring can be performed at room temperature until the metal active component precursor solution enters the composite molecular sieve, and the mixture is in a dry state. The metal active component precursor can be a salt compound of the metal active component and can be dissolved in a solvent such as water, so that it can be uniformly dispersed in the composite molecular sieve. For example, when the metal active component is Pt, the metal active component precursor includes, but is not limited to, any one or more of chloroplatinic acid and platinum nitrate. The amount of the metal active component precursor can be calculated according to the mass fraction of the metal active component in the polycyclic aromatic hydrocarbon hydrogenation saturation catalyst.

[0064] Preferably, the second drying is performed at a rate of 3-5 ℃ / min to a drying temperature of 80-120 ℃. Preferably, the second calcination is performed at a rate of 1-3 ℃ / min to a calcination temperature of 500-600 ℃, and the holding time at the calcination temperature is 1.5-3.0 h. Preferably, the second calcination is performed in a muffle furnace. Preferably, the reduction calcination is performed at a temperature of 500-600 ℃ for 3-5 h. Preferably, the reduction calcination is performed in a tube furnace.

[0065] According to another typical embodiment of the present application, a polycyclic aromatic hydrocarbon hydrogenation saturation catalyst is provided, which is prepared by any one of the above-mentioned preparation methods of the polycyclic aromatic hydrocarbon hydrogenation saturation catalyst.

[0066] The polycyclic aromatic hydrocarbon hydrogenation saturation catalyst prepared by the above-mentioned method has a micro-mesoporous pore structure, which allows the reaction and product to diffuse freely. In addition, the composite catalyst uses a USY microporous molecular sieve with strong acidity inside and an Al-SBA15 mesoporous molecular sieve with weak acidity outside. The combination of the two can not only uniform the pore size, but also neutralize the acidity to have a better synergistic and complementary effect, and has high activity for polycyclic aromatic hydrocarbon hydrogenation saturation reaction.

[0067] According to another typical embodiment of the present application, there is provided an application of the above-mentioned condensed ring aromatic hydrocarbon hydrogenation saturation catalyst in a condensed ring aromatic hydrocarbon hydrogenation saturation reaction. The above-mentioned condensed ring aromatic hydrocarbon hydrogenation saturation catalyst is applied in the hydrogenation saturation reaction of condensed ring aromatic hydrocarbons, which has high activity, good selectivity, can significantly improve the reaction yield and reduce the production cost.

[0068] The beneficial effects that can be achieved by the present application will be further illustrated below in combination with examples and comparative examples.

[0069] Example 1

[0070] 3.0g of triblock copolymer EO 20 PO 70 EO 20 and 4.66g of glacial acetic acid are weighed, stirred in a water bath at a temperature of 38℃, and dissolved in 80ml of 2mol / L hydrochloric acid. After the triblock copolymer EO 20 PO 70 EO 20 After complete dissolution, 6.24g of tetraethyl orthosilicate is added, and stirred at the above-mentioned water bath temperature for 24h. The solid product is filtered and washed for 3-5 times. 1.125g of aluminum nitrate nonahydrate is dissolved in 70ml of aqueous solution, and the aqueous solution is added to the above-mentioned filtered solid product and stirred until dissolution. Ammonia water is used to adjust the solution pH=1, and the stirring in the water bath is continued for 2h. 0.5g of USY with a silicon-aluminum ratio of 13 (macklin) is added, and the stirring is continued for 2h. The solution is moved to a hydrothermal synthesis kettle, and hydrothermal treatment is carried out at high temperature for 24h. After that, the product is filtered and washed with ultrapure water for 3-5 times. Drying is carried out in an oven at 50℃, and calcination is carried out in a muffle furnace at high temperature of 550℃ for 3h, to obtain the Al-SBA15 / USY molecular sieve. The Pt / Al-SBA15 / USY catalyst is prepared by using the same volume impregnation method. Specifically, chloroplatinic acid is placed in a beaker, and an appropriate amount of water and Al-SBA15 / USY composite molecular sieve are added. The beaker is placed on a magnetic stirrer and stirred at room temperature for 24h until dry. The stirred sample is heated in an oven at a temperature increasing rate of 3℃ / min to 100℃ for a period of time. Then, the sample is calcined in a muffle furnace at a temperature increasing rate of 2℃ / min to 550℃ and kept for a period of time. Finally, the sample is reduced in a tube furnace to obtain the Pt / Al-SBA15 / USY catalyst. The content of Pt is 1%, which is referred to as Pt / ASU13-1. The scanning electron microscope (SEM) image of the catalyst is shown in FIG. 1. Figure 1

[0071] Example 2

[0072] 3.0g of triblock copolymer EO 20 PO 70 EO 20 ​and 4.66 g of glacial acetic acid, stirring at a water bath temperature of 38 °C, dissolved in 80 ml of 2 mol / L hydrochloric acid. After the triblock copolymer E0 20 P0 70 E0 20 After complete dissolution, 6.24 g of tetraethyl orthosilicate was added, stirring at the above water bath temperature for 24 h, and then filtered and washed 3-5 times. 1.125 g of aluminum nitrate nonahydrate was weighed into 70 mL of an aqueous solution, which was added to the filtered solid product, and stirred until dissolved. The solution was adjusted to pH = 2 using ammonia water, and stirring in the water bath pot was continued for 2 h. 0.5 g of USY with a silicon-aluminum ratio of 13 (McLaren) was added, and stirring was continued for 2 h. The solution was transferred to a hydrothermal synthesis kettle, and high-temperature hydrothermal treatment was performed for 24 h. After that, the product was filtered and washed 3-5 times using ultrapure water. Drying was performed in an oven at 50 °C, and calcination was performed in a muffle furnace at a high temperature of 550 °C for 3 h, to obtain the Al-SBA15 / USY molecular sieve. The same equal-volume impregnation method as in Example 1 was used to prepare a Pt / Al-SBA15 / USY catalyst with a Pt content of 1%, which was referred to as Pt / ASU13-2.

[0073] Example 3

[0074] 3.0 g of triblock copolymer E0 20 P0 70 E0 20 and 4.66 g of glacial acetic acid, stirring at a water bath temperature of 38 °C, dissolved in 80 ml of 2 mol / L hydrochloric acid. After the triblock copolymer E0 20 P0 70 E0 20 After complete dissolution, 6.24 g of tetraethyl orthosilicate was added, stirring at the above water bath temperature for 24 h, and then filtered and washed 3-5 times. 1.125 g of aluminum nitrate nonahydrate was weighed into 70 mL of an aqueous solution, which was added to the filtered solid product, and stirred until dissolved. The solution was adjusted to pH = 2 using ammonia water, and stirring in the water bath pot was continued for 2 h. 0.5 g of USY with a silicon-aluminum ratio of 13 (McLaren) was added, and stirring was continued for 2 h. The solution was transferred to a hydrothermal synthesis kettle, and high-temperature hydrothermal treatment was performed for 24 h. After that, the product was filtered and washed 3-5 times using ultrapure water. Drying was performed in an oven at 50 °C, and calcination was performed in a muffle furnace at a high temperature of 550 °C for 3 h, to obtain the Al-SBA15 / USY molecular sieve. The same equal-volume impregnation method as in Example 1 was used to prepare a Pt / Al-SBA15 / USY catalyst with a Pt content of 1%, which was referred to as Pt / ASU13-2.

[0075] Example 4

[0076] 3.0 g of triblock copolymer E0 20 P0 70 E0 20and 4.66 g of glacial acetic acid, stirring at a water bath temperature of 38 °C, dissolved in 80 ml of 2 mol / L hydrochloric acid. After the triblock copolymer E0 20 P0 70 E0 20 After complete dissolution, 6.24 g of tetraethyl orthosilicate was added, stirring at the above water bath temperature for 24 h, and then filtered and washed 3-5 times. 1.125 g of aluminum nitrate nonahydrate was weighed into 70 mL of an aqueous solution, which was added to the filtered solid product, and stirred until dissolved. The solution was adjusted to pH = 4 using ammonia water, and stirring in the water bath pot was continued for 2 h. 0.5 g of USY with a silica-alumina ratio of 13 (McClen) was added, and stirring was continued for 2 h. The solution was transferred to a hydrothermal synthesis kettle, and high-temperature hydrothermal treatment was performed for 24 h. After that, the product was filtered and washed 3-5 times using ultrapure water. Drying was performed in an oven at 50 °C, and calcination was performed in a muffle furnace at a high temperature of 550 °C for 3 h, to obtain the Al-SBA15 / USY molecular sieve. The same equal-volume impregnation method as in Example 1 was used to prepare a Pt / Al-SBA15 / USY catalyst with a Pt content of 1%, which was referred to as Pt / ASU13-4.

[0077] Example 5

[0078] 3.0 g of triblock copolymer E0 20 P0 70 E0 20 and 4.66 g of glacial acetic acid, stirring at a water bath temperature of 38 °C, dissolved in 80 ml of 2 mol / L hydrochloric acid. After the triblock copolymer E0 20 P0 70 E0 20 After complete dissolution, 6.24 g of tetraethyl orthosilicate was added, stirring at the above water bath temperature for 24 h, and then filtered and washed 3-5 times. 1.125 g of aluminum nitrate nonahydrate was weighed into 70 mL of an aqueous solution, which was added to the filtered solid product, and stirred until dissolved. The solution was adjusted to pH = 4 using ammonia water, and stirring in the water bath pot was continued for 2 h. 0.5 g of USY with a silica-alumina ratio of 13 (McClen) was added, and stirring was continued for 2 h. The solution was transferred to a hydrothermal synthesis kettle, and high-temperature hydrothermal treatment was performed for 24 h. After that, the product was filtered and washed 3-5 times using ultrapure water. Drying was performed in an oven at 50 °C, and calcination was performed in a muffle furnace at a high temperature of 550 °C for 3 h, to obtain the Al-SBA15 / USY molecular sieve. The same equal-volume impregnation method as in Example 1 was used to prepare a Pt / Al-SBA15 / USY catalyst with a Pt content of 1%, which was referred to as Pt / ASU13-4.

[0079] Example 6

[0080] 3.0 g of triblock copolymer E0 20 P0 70 E0 20and 4.66 g of glacial acetic acid, stirring at a water bath temperature of 38 °C, dissolved in 80 ml of 2 mol / L hydrochloric acid. After the triblock copolymer E0 20 P0 70 E0 20 After complete dissolution, 6.24 g of tetraethyl orthosilicate was added, stirring at the above water bath temperature for 24 h, and the product was filtered and washed 3-5 times. 1.125 g of aluminum nitrate nonahydrate was weighed into 70 mL of an aqueous solution, which was added to the filtered solid product, and stirring was continued until dissolution. The solution was adjusted to pH = 2 using ammonia water, and stirring was continued in the water bath for 2 h. 0.5 g of USY with a silica-alumina ratio of 70 (McClen) was added, and stirring was continued for 2 h. The solution was transferred to a hydrothermal synthesis kettle, and high-temperature hydrothermal treatment was performed for 24 h. The product was then filtered and washed 3-5 times using ultrapure water. Drying was performed in an oven at 50 °C, and calcination was performed in a muffle furnace at a high temperature of 550 °C for 3 h, thereby obtaining an Al-SBA15 / USY molecular sieve. The same equal-volume impregnation method as in Example 1 was used to prepare a Pt / Al-SBA15 / USY catalyst with a Pt content of 1%, which was referred to as Pt / ASU70-2.

[0081] Example 7

[0082] 3.0 g of triblock copolymer E0 20 P0 70 E0 20 and 4.66 g of glacial acetic acid, stirring at a water bath temperature of 38 °C, dissolved in 80 ml of 2 mol / L hydrochloric acid. After the triblock copolymer E0 20 P0 70 E0 20 After complete dissolution, 6.24 g of tetraethyl orthosilicate was added, stirring at the above water bath temperature for 24 h, and the product was filtered and washed 3-5 times. 1.125 g of aluminum nitrate nonahydrate was weighed into 70 mL of an aqueous solution, which was added to the filtered solid product, and stirring was continued until dissolution. The solution was adjusted to pH = 2 using ammonia water, and stirring was continued in the water bath for 2 h. 0.5 g of USY with a silica-alumina ratio of 115 (McClen) was added, and stirring was continued for 2 h. The solution was transferred to a hydrothermal synthesis kettle, and high-temperature hydrothermal treatment was performed for 24 h. The product was then filtered and washed 3-5 times using ultrapure water. Drying was performed in an oven at 50 °C, and calcination was performed in a muffle furnace at a high temperature of 550 °C for 3 h, thereby obtaining an Al-SBA15 / USY molecular sieve. The same equal-volume impregnation method as in Example 1 was used to prepare a Pt / Al-SBA15 / USY catalyst with a Pt content of 1%, which was referred to as Pt / ASU115-2.

[0083] Comparative Example 1

[0084] The same USY molecular sieve as in Example 1 (the same as the USY molecular sieve in Example 1) was mixed with the Al-SBA15 molecular sieve in a ratio of 1:1, and a composite catalyst was prepared using the same method as in Example 1 by using the equal-volume impregnation method.

[0085] Comparative Example 2

[0086] 3.0 g of the triblock copolymer EO 20 PO 70 EO 20 and 4.66 g of glacial acetic acid were weighed out, dissolved in 80 ml of 2 mol / L hydrochloric acid under stirring at a water bath temperature of 38°C. After the triblock copolymer EO 20 PO 70 EO 20 6.24 g of tetraethyl orthosilicate was added after complete dissolution, and stirring was continued at the above water bath temperature for 24 h. The solid product was filtered and washed 3-5 times, 1.125 g of aluminum nitrate nonahydrate was dissolved in 70 ml of water solution, and the water solution was added to the filtered solid product and stirred until dissolution. Ammonia water was used to adjust the solution pH to 1, and stirring was continued in the water bath for 2 h. The solution was transferred to a hydrothermal synthesis kettle, and high-temperature hydrothermal treatment was performed for 24 h. After that, the product was filtered and washed 3-5 times with ultrapure water. Drying was performed in an oven at 50°C, and calcination was performed in a muffle furnace at a high temperature of 550°C for 3 h, to obtain the Al-SBA15 molecular sieve. Then, a composite catalyst was prepared using the equal-volume impregnation method in the same manner as in Example 1.

[0087] The composite catalysts prepared in the above examples and comparative examples were subjected to property testing in the following manner, and the test results are listed in Table 1.

[0088] Acid amount: tested by connecting a pyridine infrared device (Dalian Institute of Chemical Physics, Chinese Academy of Sciences) with a BRUKER Fourier infrared spectrometer TENSOR 27 produced in Germany. The test procedure was as follows: 10 mg of powder was pressed into a non-defective circular sheet in a standard mold, and was loaded into an analysis cell, and was subjected to 1 h of pretreatment under vacuum at 400°C. After cooling to room temperature, pyridine adsorption was started. The sample was then heated to 150°C and 300°C respectively, and was kept for 0.5 h, and then was lowered to room temperature, and a Py-IR spectrum was collected. In the spectrum, the peaks at 1540 cm -1 and 1450 cm -1 correspond to the absorption peaks of and Lewis acid sites. And the calculation was performed according to the formula, in which R refers to the radius of the catalyst sheet, which was 0.65 cm.

[0089] C (mmol / g) = 1.42A L R 2 / W

[0090] C (mmol / g) = 1.88A B R 2 / W

[0091] Average pore size: The N2adsorption-desorption curves of the supports and catalysts involved in this paper were determined by using Autosor-iQ physical adsorption instrument produced by Quantachrome Corporation of the United States. The testing process is as follows: 100 mg of sample was placed in the test tube, and the moisture and impurities in the sample were removed under the condition of temperature of 160°C and vacuum. Subsequently, N2adsorption test was carried out under liquid nitrogen cooling.

[0092] Table 1

[0093]

[0094] According to the test data, it can be seen that with the increase of the pH value of the solution adjusted by ammonia water, the pore size of the catalyst shows a trend of first increasing and then decreasing.

[0095] The comparison of the results of pyridine infrared test of the catalysts of Examples 5-7 shows that with the increase of the silicon-aluminum ratio of the USY molecular sieve, the acidity of the composite catalyst prepared gradually decreases.

[0096] Application Example 1

[0097] The catalysts prepared in the above examples and comparative examples were respectively used for the hydrogenation saturation reaction of anthracene, and the reaction conditions were as follows: the temperature was 240°C, the pressure was 4 MPa, the rotation speed was 600 rpm, the reaction time was 12 h, and the raw material anthracene was all converted, wherein the selectivity of the target product perhydroanthracene when using different examples or comparative examples was as shown in Table 2. Among them, when using the catalyst prepared in Example 2, the products of the reaction system at different reaction times were as shown in Table 3. Figure 2

[0098] Table 2

[0099] Catalyst Selectivity Example 1 97.12％ Example 2 98.89％ Example 3 97.32％ Example 4 95.33％ Example 5 98.15％ Example 6 96.85％ Example 7 93.11％ Comparative Example 1 54.63％ Comparative Example 2 97.13％

[0100] Application Example 2

[0101] Under the conditions of temperature of 360°C, hydrogen pressure of 6 MPa, and space velocity of 6 h -1 , the hydrogenation reaction of coal direct liquefaction product was carried out using the catalyst of Example 2, and the hydrogenation effect was good. The selectivity of straight-chain hydrocarbon in the hydrogenated product was 16.7%, the selectivity of part of saturated intermediates was 24.9%, the selectivity of naphthenes was 55.0%, and other products were 4.9%.

[0102] ​From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects: the preparation method of the present application adjusts the pore structure and acid amount of the carrier of the condensed ring aromatic hydrocarbon hydrogenation saturation catalyst, the prepared condensed ring aromatic hydrocarbon hydrogenation saturation catalyst has a micro-mesopore pore structure, which can make the reaction and product freely diffuse, meanwhile, the strong acid USY microporous molecular sieve is used inside the composite catalyst, and the weak acid Al-SBA15 mesoporous molecular sieve is used outside the composite catalyst, the two are compounded to prepare a catalyst with uniform pore size and neutralized acid, which has better synergistic and complementary effects, and has higher activity for the condensed ring aromatic hydrocarbon hydrogenation saturation reaction.

[0103] The above merely describes the preferred embodiments of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a saturated catalyst for the hydrogenation of polycyclic aromatic hydrocarbons, characterized in that, Includes the following steps: Step S1: Mix the structure-directing agent, silicon source and solvent, stir, wash, and obtain a solid intermediate product; Step S2: The solid intermediate product and aluminum salt solution are mixed and dissolved, and ammonia water is added to the solution to adjust the pH value. The reaction is carried out under stirring conditions. Step S3: Mix the reaction product of step S2 with USY molecular sieve, carry out hydrothermal reaction, filter, wash, and obtain hydrothermal reaction product; Step S4: The hydrothermal reaction product is subjected to a first drying and a first calcination to obtain Al-SBA15 / USY composite molecular sieve. Step S5: Load the Al-SBA15 / USY composite molecular sieve with a metal active component to obtain the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons.

2. The method for preparing the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons according to claim 1, characterized in that, The structure-directing agent comprises a triblock copolymer EO. 20 PO 70 EO 20 EO 106 PO 70 EO 106 Any one or more of the following; The silicon source includes any one or more of tetraethyl orthosilicate, methyl orthosilicate, and silica sol; The mass ratio of the structure guiding agent to the silicon source is 0.5 to 1.0; The solvent in step S1 includes hydrochloric acid and acetic acid, preferably, the concentration of hydrochloric acid is 0.5-2.5 mol / L; The stirring in step S1 lasts for 20-28 hours.

3. The method for preparing the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons according to claim 1, characterized in that, The aluminum salt is any one or more of aluminum nitrate nonahydrate, aluminum chloride hexahydrate, and aluminum isopropoxide; In step S2, the mass ratio of the solid intermediate product to the aluminum salt is 0.2 to 0.

8. In step S2, ammonia is added to adjust the pH value to 1-4. In step S2, the reaction time is 2-5 hours; the reaction temperature is 25℃-40℃.

4. The method for preparing the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons according to claim 1, characterized in that, The silica-to-alumina ratio of the USY molecular sieve is 13–115.

5. The method for preparing the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons according to claim 1, characterized in that, The hydrothermal reaction is carried out at a temperature of 120℃-180℃ for 20-30 hours. Preferably, the hydrothermal reaction is carried out under static conditions.

6. The method for preparing the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons according to claim 1, characterized in that, In step S4, the heating rate of the first drying process is 3-5℃ / min, the temperature is raised to 50-70℃, and the temperature is maintained for 12h to 24h. In step S4, the temperature of the first roasting is 500-600℃, the holding time is 1.5-3.5h, and preferably the heating rate during the first roasting is 1-3℃ / min. In step S4, the mass ratio of USY molecular sieve to Al-SBA15 molecular sieve in the Al-SBA15 / USY composite molecular sieve is 1:2-1:

10.

7. The method for preparing the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons according to any one of claims 1 to 6, characterized in that, The active metal component is any one or more of Pt, Pb, and Ru; preferably, the active metal component is Pt. The mass fraction of the metal active component in the hydrogenation saturated catalyst for polycyclic aromatic hydrocarbons is 0.5 wt% to 1.5 wt%. In step S5, the method for loading the metal active component is the equal volume impregnation method.

8. The method for preparing the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons according to claim 7, characterized in that, Step S5 includes: The Al-SBA15 / USY composite molecular sieve was mixed with a metal active component precursor solution, stirred at room temperature, and subjected to a second drying, a second calcination, and a reduction calcination to obtain the saturated catalyst for hydrogenation of polycyclic aromatic hydrocarbons. Preferably, during the second drying process, the temperature is increased to the drying temperature at a rate of 3-5°C / min, and the drying temperature of the second drying is 80-120°C. Preferably, during the second calcination, the temperature is increased to the calcination temperature at a rate of 1-3℃ / min, the calcination temperature of the second calcination is 500-600℃, and the holding time at the calcination temperature is 1.5h to 3.0h; preferably, the second calcination is carried out in a muffle furnace. Preferably, the reduction roasting temperature is 500-600℃ and the time is 3-5h; preferably, the reduction roasting is carried out in a tube furnace.

9. A saturated catalyst for the hydrogenation of polycyclic aromatic hydrocarbons, characterized in that, It was prepared by the method for preparing the hydrogenation saturated catalyst for polycyclic aromatic hydrocarbons according to any one of claims 1 to 8.

10. The application of the hydrogenation saturation catalyst for polycyclic aromatic hydrocarbons according to claim 9 in the hydrogenation saturation reaction of polycyclic aromatic hydrocarbons.

Images