A catalytic cracking light cycle oil refining catalyst system and its application

Abstract

This invention provides a catalyst system for refining light cycle oil from catalytic cracking and its application, primarily addressing the contradiction between monocyclic aromatic hydrocarbon selectivity and denitrification rate in previous technologies. The catalyst system provided by this invention exhibits high monocyclic aromatic hydrocarbon selectivity and high denitrification rate. It utilizes Al2O3 and Al2O3-SiO2-molecular sieve multi-component composite supports as carriers, and at least two components selected from NiO, MoO3, WO3, and P2O5 as active components. Under mild process conditions, this system effectively solves the problem and can be used in industrial production for refining light cycle oil from catalytic cracking and increasing the added value of catalytic diesel.

Description

Technical Field

[0001] This invention relates to the field of refining technology for catalytic cracking light cycle oil, specifically to a catalyst system for refining catalytic cracking light cycle oil and its application. Background Technology

[0002] Light cycle oil (LCO) from catalytic cracking is a low-quality diesel fraction. Its main compositional characteristics are as follows: total aromatics content is as high as 80%, with naphthalene-based bicyclic aromatics accounting for about 70%, monocyclic and tricyclic aromatics each accounting for about 15%, and the remainder being alkanes, cycloalkanes, and alkenes. LCO has a sulfur content of 0.2–1.5 wt%, a nitrogen content of 100–1000 ppm, a cetane number of only 15–25, and poor ignition performance.

[0003] Catalytic cracking light cycle oil exhibits poor stability, rapidly increasing gum content and darkening color during storage and transportation, severely impacting its usability. The main reason for this poor stability is the presence of large amounts of basic and non-basic nitrogen compounds, thiols, and thiophenols, with nitrogen compounds having a particularly significant impact. Nitrogen compounds in catalytic cracking diesel are classified into basic and non-basic nitrogen compounds, and the NO produced after combustion... x Emissions into the atmosphere are a major contributor to acid rain and smog. Furthermore, the presence of nitrogen compounds severely affects the depth of sulfur removal. On one hand, during hydrodesulfurization, nitrogen compounds and sulfides compete for adsorption at the active sites of the catalyst, with nitrogen compounds exhibiting stronger adsorption capacity, thus inhibiting the hydrodesulfurization reaction. On the other hand, basic nitrogen-containing compounds can poison the hydrodesulfurization catalyst.

[0004] Producing high-quality diesel fuel with low sulfur, low aromatics, and high cetane number is gradually becoming the production trend for vehicle diesel fuel. On the other hand, diesel fuel produced using existing technologies has a high content of aromatics and cycloalkanes. These aromatics and cycloalkanes contribute little to the cetane number of diesel fuel, making it difficult for diesel products to meet the required cetane number standards. Therefore, reducing the content of aromatics and cycloalkanes in diesel fuel has become a real challenge for refineries in upgrading diesel fuel quality.

[0005] Currently, the most common processing methods for LCO are hydrorefining and hydrocracking. Hydrorefining of LCO mainly involves desulfurization, denitrogenation, and selective hydrogenation saturation reactions of aromatics, which can improve its color and stability, but the increase in cetane number is relatively small, far from meeting the cetane number requirements for automotive diesel. Hydrocracking processes, such as UOP's Unicracking process, can produce gasoline, jet fuel, and diesel products, but when the proportion of secondary processed oils such as LCO is too high, qualified jet fuel products cannot be obtained.

[0006] Nova's Arorincle process employs an independent two-stage hydrogen cycle reaction system. Stage I uses Ni / Mo or Ni / W catalysts for the hydrorefining of LCO feedstock, while Stage II uses a Pd / zeolite bifunctional catalyst for selective conversion. The hydrogen cycle systems for Stage I and Stage II are independent of each other. The aromatics yield is approximately 35%, but the purity is relatively low. Due to the use of precious metals as the hydrogenation functional component, it exhibits poor sulfur resistance and high cost.

[0007] Research on catalysts for the hydrotreating of heavy distillate oils has long been one of the most active areas of research. Alumina-supported Co(Ni)Mo(W) / Al₂O₃ catalysts were first applied in industrial hydrotreating reactions as early as 1943 and remain commonly used catalysts in many hydrorefining processes. Currently, the most common combination of active components in typical hydrotreating catalysts is Co-Mo, Ni-Mo, and Ni-W, which typically contain 1-4 wt% Co(Ni)O, 8-16 wt% MoO₃, or 12-25 wt% WO₃.

[0008] US5300212 discloses a process for hydrorefining inferior heavy oil. This method involves the conversion of heavy oil feedstock, hydrogen, and catalyst in two reactors. Specifically, the feedstock and a dispersed catalyst with molybdenum phosphate as a precursor first enter a first slurry-bed hydrorefining reactor, where a conversion reaction occurs at 343–482°C and 0.345–34.5 MPa. The reaction products, after separation, enter a second fluidized bed hydrorefining reactor, where conversion occurs at 343–399°C and 5.5–27.6 MPa under the action of a supported catalyst. The reaction products then enter a distillation column, yielding a <524°C fraction and a >524°C fraction. The <524°C fraction is used as the product, while the >524°C heavy fraction is recycled back to the second reactor. This process can refining inferior heavy oil. However, because the first reactor uses a dispersed catalyst and the second reactor uses a supported catalyst, catalyst particles carried out from the first reactor can easily clog the pores of the heavily supported catalyst in the second reactor or cover the active sites of the catalyst, causing catalyst deactivation and affecting the overall operating cycle.

[0009] CN1064988C discloses a method for hydroconversion of diesel fractions. This method uses a hydroconversion catalyst containing molecular sieves and employs a single-stage, tandem single-stage, and two-stage hydroconversion process to remove aromatics, desulfurize, and improve the cetane number of low-quality diesel, especially LCO. However, the diesel produced by this method has low specifications; its sulfur and nitrogen content, aromatics, and cetane number do not meet current national standards. A large amount of aromatic components in the catalytic cracking diesel feedstock are hydrosaturated and not effectively utilized.

[0010] The gasoline hydrotreating catalyst disclosed in CN85104438 uses high-purity alumina as a support, tungsten and nickel as active components, and fluorine as an auxiliary agent. The fluorine in this catalyst is easily lost during industrial operation, and it corrodes equipment and pollutes the environment.

[0011] CN1872959A discloses a hydrogenation catalyst using alumina as a support, nickel, molybdenum, and tungsten as active components, and fluorine as an auxiliary agent. Compared with traditional bimetallic hydrogenation catalysts, the trimetallic catalyst provided by this catalyst exhibits improved activity. However, due to limitations in support performance and other factors, the improvement is limited, and the activity remains relatively low. Furthermore, this catalyst also faces challenges such as fluorine loss during industrial operation, fluorine corrosion of equipment, and environmental pollution.

[0012] CN1040610A discloses a hydrorefining catalyst supported on γ-Al₂O₃ containing TiO₂. The supported catalyst γ-Al₂O₃ contains 5-30% titanium oxide, with W, Mo, and Ni as active components. The performance of the hydrorefining catalyst supported on TiO₂-modified Al₂O₃ is improved to some extent. However, the support has a lower acidity, especially fewer moderately strong acid centers, which is unfavorable for the ring-opening and breaking of nitrogen heterocycles, resulting in a less significant denitrification effect.

[0013] The petroleum hydrocarbon hydrotreating method proposed in USP4880524 employs a highly active hydrogenation catalyst. This catalyst is of the Ni-Mo / Al₂O₃ type with a specific surface area greater than 300 m². 2 / g, with pore sizes smaller than 7nm exceeding 70%. This catalyst exhibits good hydrorefining activity for light distillate oils, but its hydrorefining effect on catalytic cracking light cycle oils is poor. Summary of the Invention

[0014] Given that the existing technologies use Al2O3 or Al2O3-SiO2 as supports, they suffer from problems such as small specific surface area, fewer medium-to-strong acid centers, and low acid density, resulting in low conversion rates of bicyclic aromatic hydrocarbons, poor selectivity of monocyclic aromatic hydrocarbons, and weak denitrification capabilities in the feedstock. At the same time, because the support is prone to forming strong interactions with the active components, generating a new phase without catalytic activity and containing only L-acids, in the hydrotreating of high-nitrogen catalytic diesel, the L-acid centers of Al2O3 are prone to strong adsorption with basic nitrogen, inhibiting the deep hydrotreating desulfurization and denitrification performance of the catalyst. One objective of this invention is to provide a catalyst system in which the first catalyst component is supported by Al2O3, which has weak acidity and a relatively low reaction temperature. This allows for the selective hydrogenation of easily hydrogenated tricyclic and bicyclic aromatics to monocyclic aromatics, while preventing the conversion of difficult-to-hydrogenate monocyclic aromatics. The second catalyst component is supported by an Al2O3-SiO2-molecular sieve multi-component composite support, which increases the acidity of the support and contains molecular sieves. The Brønsted acid of the molecular sieves can cause the branching or isomerization of nitrogen-containing compounds such as carbazole at relatively high temperatures, thereby exposing carbazole to the active sites of the catalyst, facilitating the breaking of CN bonds, and simultaneously improving the selectivity of monocyclic aromatics. The catalyst system provided by this invention is applied to the hydrorefining of catalytic cracking light cycle oil, effectively improving the retention rate of aromatics and the denitrification rate in the product. Using the catalyst system of this invention in the hydrorefining of catalytic cracking light cycle oil under relatively mild reaction conditions (inlet temperature 270℃, reaction pressure 6.0MPa, H2 / Oil molar ratio 1200, feed liquid hourly space velocity 0.8h), -1 The selectivity for monocyclic aromatic hydrocarbons is 89%, the nitrogen content of the products is less than 10 ppm, and the cracking gases (CH4, C2H6, C3H8, C4H) are... 10 With a total content of less than 500 ppm, the product can be directly used as a blending component for gasoline and diesel or as a high-quality raw material for the production of BTX, which greatly enhances the added value of the product.

[0015] The second objective of this invention is to provide a catalyst system corresponding to the first objective for application in the refining of light cycle oil from catalytic cracking.

[0016] To achieve one of the above objectives, the technical solution adopted by the present invention is as follows:

[0017] A catalyst system for refining light cycle oil from catalytic cracking includes: a first catalyst component and a second catalyst component.

[0018] The first catalyst component includes a first support and a first modifying component. The first support is Al2O3, preferably γ-Al2O3. The first modifying component is selected from at least two of NiO, MoO3, WO3 and P2O5, preferably selected from at least two of NiO, MoO3 and P2O5, and more preferably includes NiO and MoO3.

[0019] The second catalyst component includes a second support and a second modified component. The second support is an Al2O3-SiO2-molecular sieve multi-component composite support. The second modified component is selected from at least two of NiO, MoO3, WO3 and P2O5, preferably from at least three of NiO, MoO3, WO3 and P2O5, and more preferably includes NiO, MoO3, WO3 and P2O5.

[0020] The inventors of this application discovered in their research that Ni, Mo, W, and P, as well as Al2O3 and Al2O3-SiO2-molecular sieve composite supports, have a synergistic effect on improving the selectivity and denitrification rate of monocyclic aromatics in catalytic cracking light cycle oil. The catalyst system provided by this invention can solve the problem of the contradiction between monocyclic aromatic selectivity and denitrification rate in catalytic cracking light cycle oil refining catalysts in previous technologies.

[0021] In some preferred embodiments of the present invention, the volume ratio of the first catalyst component to the second catalyst component is (1-8):(2-9), preferably (2-7):(3-8), and more preferably (3-5):(5-7).

[0022] In some preferred embodiments of the present invention, the Al2O3-SiO2-molecular sieve multi-component composite carrier has an Al2O3 mass percentage of 72% to 97%, an SiO2 mass percentage of 2% to 10%, and a molecular sieve mass percentage of 1% to 18%.

[0023] In some preferred embodiments of the present invention, in the Al2O3-SiO2-molecular sieve multi-component composite support, the Al2O3 is γ-Al2O3, and the molecular sieve is selected from at least one of HZSM-5, HMor, Hβ, and layered hierarchical porous HZSM-5-MCM-41, more preferably layered hierarchical porous HZSM-5-MCM-41.

[0024] In some preferred embodiments of the present invention, the layered hierarchical porous HZSM-5-MCM-41 has at least one of the following characteristics:

[0025] 1) The layered hierarchical porous ZSM-5-MCM-41 has a Brønsted acid to Lewis acid ratio of (2-4):1 at 400℃ and a Brønsted acid to Lewis acid ratio of (2-5):1 at 300℃;

[0026] 2) In the layered hierarchical porous ZSM-5-MCM-41, the ratio of medium-strong acid to total acid is (0.55~0.85):1, preferably (0.6~0.8):1;

[0027] 3) The mesopore volume to micropore volume ratio of the layered hierarchical porous ZSM-5-MCM-41 is 8–15, the pore size is 5–10 nm, and the pore volume is 0.5–0.8 cm³. 3 / g, specific surface area greater than 300m² 2 ·g -1 ;

[0028] 4) The molar ratio of silica to alumina in the layered multi-level porous ZSM-5-MCM-41 is (20-200):1, preferably (20-60):1.

[0029] According to the present invention, the prepared layered hierarchical porous ZSM-5-MCM-41 can be converted into hydrogen-type molecular sieves according to methods well known to those skilled in the art. The conversion can be carried out at the raw powder stage or after molding, without particular limitation, and comparable technical effects can be obtained in both cases.

[0030] As an example, in a specific embodiment of the present invention, the conversion of layered hierarchical porous ZSM-5-MCM-41 molecular sieve into hydrogen-form molecular sieve is carried out at the raw powder stage, which may specifically include the following steps: using 0.1~1.0mol·L -1 An ammonium nitrate solution with a solid-liquid ratio of 1:10 to 1:20 was heated at 60 to 120°C and stirred for 1 to 5 hours, then filtered and washed. This process was repeated three times. The resulting sample was dried at 60 to 150°C for 4 to 8 hours and finally calcined at 250 to 750°C for 2 to 12 hours to obtain hydrogen-form layered hierarchical porous ZSM-5-MCM-41 molecular sieve.

[0031] For comparison only, the steps for converting molecular sieves into hydrogen-form molecular sieves in a specific embodiment of the present invention are as follows: using 0.2 mol·L -1 An ammonium nitrate solution with a solid-liquid ratio of 1:15 was heated at 90°C and stirred for 2 hours, then filtered and washed. This process was repeated three times. The resulting sample was dried at 120°C for 6 hours and finally calcined at 550°C for 5 hours to obtain a hydrogen-form layered hierarchical porous ZSM-5-MCM-41 molecular sieve. The ratio of moderately strong acid to total acid was 0.55–0.85, the ratio of mesopore volume to micropore volume was 8–15, the interlayer thickness was 5–10 nm, the pore size was 5–10 nm, and the specific surface area was greater than 400 m². 2 ·g -1 .

[0032] According to the present invention, HZSM-5, HMor, and Hβ respectively have the following properties:

[0033] The molar ratio of silicon dioxide to aluminum oxide in HZSM-5 is (20–60):1, the particle size is 0.1–1 micrometer, and the pore volume is 0.18–0.22 cm³. 3 / g, specific surface area greater than 300m²2 ·g -1 ;

[0034] The molar ratio of silica to aluminum oxide in HMor is (20–60):1, the particle size is 0.1–1.5 micrometers, and the pore volume is 0.25–0.35 cm³. 3 / g, specific surface area greater than 450m² 2 ·g -1 ;

[0035] The molar ratio of silicon dioxide to aluminum oxide in Hβ is (20–60):1, the particle size is 0.1–1.5 micrometers, and the pore volume is 0.4–0.6 cm³. 3 / g, specific surface area greater than 450m² 2 ·g -1 ;

[0036] In some preferred embodiments of the present invention, the first catalyst component is disposed in the upper layer of the catalyst bed, and the second catalyst component is disposed in the lower layer of the catalyst bed; preferably, the first catalyst component and the second catalyst component are configured to be in direct contact in the same reactor.

[0037] In some preferred embodiments of the present invention, the mass percentage of the first support in the first catalyst component is 50% to 80%, preferably 60% to 74%, based on the total weight of the first catalyst component, and the mass percentage of the first modified component is 20% to 50%, preferably 20% to 30%.

[0038] In some preferred embodiments of the present invention, the first catalyst component, based on the total weight of the first catalyst component, has the following mass percentages: NiO 3%–10%, MoO3 5%–25%, WO3 12%–16%, and P2O5 0.1%–1%.

[0039] In some specific embodiments of the present invention, the content of NiO in the first catalyst component is 50-120 g / L, preferably 60-100 g / L; and the content of MoO3 is 150-250 g / L, preferably 180-220 g / L.

[0040] In some preferred embodiments of the present invention, the second catalyst component, based on the total weight of the second catalyst component, has a mass percentage content of 50% to 80%, preferably 55% to 70%, and a mass percentage content of 20% to 50%, preferably 25% to 45%.

[0041] In some preferred embodiments of the present invention, the second catalyst component, based on the total weight of the second catalyst component, has the following mass percentages: NiO 3%–8%, MoO3 5%–10%, WO3 12%–30%, and P2O5 0.1%–1%.

[0042] In some specific embodiments of the present invention, the second catalyst component contains 20-100 g / L NiO, preferably 30-70 g / L, 50-120 g / L MoO3, preferably 60-100 g / L, 100-200 g / L WO3, preferably 120-180 g / L, and 1-20 g / L P2O5, preferably 2-10 g / L.

[0043] In some preferred embodiments of the present invention, the specific surface area of ​​the first carrier is 190 m². 2 / g~250m 2 / g, with an average pore size of 8–12 nm and a pore volume of 0.7–0.85 cm³. 3 / g.

[0044] In some preferred embodiments of the present invention, the specific surface area of ​​the second carrier is 280 m². 2 / g~380m 2 / g, with an average pore size of 5–10 nm and a pore volume of 0.55–0.75 cm³. 3 / g.

[0045] In some preferred embodiments of the present invention, the preparation method of the first carrier includes the following steps:

[0046] S11. Mix Al2O3 raw powder and the first additive to obtain the first mixture;

[0047] S12. Mix the first mixture and the first molding aid to obtain a second mixture;

[0048] S13. The second mixture is subjected to molding treatment to obtain the first catalyst precursor;

[0049] S14. The first catalyst precursor is dried and calcined sequentially to obtain the first support.

[0050] In some preferred embodiments of the present invention, in step S11, the average particle size of the Al2O3 raw powder is 0.1 to 2 micrometers; the first binder is selected from at least one of guar gum powder and hydroxymethyl cellulose.

[0051] In some preferred embodiments of the present invention, in step S11, the mass ratio of the Al2O3 raw powder to the first auxiliary agent is 100:(1.5~5).

[0052] In some preferred embodiments of the present invention, in step S12, the first molding aid is an aqueous solution containing nitric acid and / or ammonium bicarbonate. Preferably, the mass percentage of nitric acid is 1.2% to 3.0%, and the mass percentage of ammonium bicarbonate is 1% to 5%. More preferably, the mass percentage of nitric acid is 1.5% to 2.5%, and the mass percentage of ammonium bicarbonate is 1% to 2.5%.

[0053] In some preferred embodiments of the present invention, in step S12, the mass ratio of the first mixture to the first molding aid is 4:(3.5 to 4.5).

[0054] In some preferred embodiments of the present invention, the molding process in step S13 is a conventional technique in the art, and the present invention does not intend to impose too many restrictions on it.

[0055] In some preferred embodiments of the present invention, in step S14, the calcination conditions include: a temperature of 450°C to 650°C, preferably 500°C to 600°C; and a time of 1 hour to 12 hours, preferably 2 hours to 5 hours.

[0056] According to the present invention, in step S14, the calcination atmosphere is not particularly required; both oxidizing and inert atmospheres are acceptable and can achieve comparable technical effects. Oxidizing atmospheres include, but are not limited to, atmospheres containing oxygen; from an economic perspective, an air atmosphere is preferred. Inert atmospheres include, but are not limited to, at least one of nitrogen or an inert gas atmosphere, where the inert gas can be nitrogen, helium, argon, etc. From an economic perspective, nitrogen is commonly chosen as the inert atmosphere. For comparability, an air atmosphere is used in all embodiments of the present invention.

[0057] According to the present invention, the drying in step S14 is a conventional operation in the art, and the present invention does not intend to impose excessive limitations on it. Exemplarily, in some specific embodiments, the drying conditions may be: a temperature of 90℃~150℃, preferably 100℃~120℃; and a time of 1h~24h, preferably 2h~12h.

[0058] According to the present invention, in step S14, the product can be left to air dry at room temperature for a period of time before the drying process, and the air drying time can be 12h to 48h.

[0059] According to the present invention, in the context of the present invention, room temperature can be any temperature value within the temperature range of 20°C to 35°C.

[0060] In some preferred embodiments of the present invention, the method for preparing the second carrier includes the following steps:

[0061] S21. Mix Al2O3 powder containing SiO2, molecular sieve, and second auxiliary agent to obtain mixture A;

[0062] S22. Mix the mixture A and the second molding aid to obtain mixture B;

[0063] S23. The mixture B is subjected to molding treatment to obtain a second catalyst precursor;

[0064] S24. The second catalyst precursor is dried and calcined sequentially to obtain the second support.

[0065] In some preferred embodiments of the present invention, in step S21, the mass percentage of SiO2 in the Al2O3 powder containing SiO2 is 1% to 9%; the particle size of the Al2O3 powder containing SiO2 is 0.1 to 3 micrometers; and the binder is selected from at least one of guar gum powder, hydroxymethyl cellulose, carbon black, starch, and carbon fiber.

[0066] In some preferred embodiments of the present invention, in step S21, the mass ratio of Al2O3 powder containing SiO2, molecular sieve and second auxiliary agent is 100:(1.5-5).

[0067] In some preferred embodiments of the present invention, in step S22, the second molding aid is an aqueous solution containing nitric acid and / or boric acid and / or phosphoric acid. Preferably, the mass percentage of nitric acid is 1% to 5%, the mass percentage of boric acid is 1% to 5%, and the mass percentage of phosphoric acid is 1% to 5%.

[0068] In some preferred embodiments of the present invention, in step S22, the mass ratio of the mixture A and the second molding aid is 4:(3.5 to 4.5).

[0069] In some preferred embodiments of the present invention, in step S24, the calcination conditions include: a temperature of 450°C to 650°C, preferably 500°C to 600°C; and a time of 1 hour to 12 hours, preferably 2 hours to 6 hours.

[0070] According to the present invention, in step S24, the calcination atmosphere is not particularly required; both oxidizing and inert atmospheres are acceptable and can achieve comparable technical effects. Oxidizing atmospheres include, but are not limited to, atmospheres containing oxygen, with air being preferred from an economic perspective. Inert atmospheres include, but are not limited to, at least one of nitrogen or inert gas atmospheres, where the inert gas can be nitrogen, helium, argon, etc. From an economic perspective, nitrogen is commonly chosen as the inert atmosphere. For comparability, air atmospheres are used in all embodiments of the present invention.

[0071] According to the present invention, the drying in step S24 is a conventional operation in the art, and the present invention does not intend to impose excessive limitations on it. Exemplarily, in some specific embodiments, the drying conditions may be: a temperature of 90℃~150℃, preferably 100℃~120℃; and a time of 1h~24h, preferably 2h~12h.

[0072] According to the present invention, in step S24, the product can be left to air dry at room temperature for a period of time before the drying process, and the air drying time can be 12h to 48h.

[0073] In some preferred embodiments of the present invention, the preparation method of the layered hierarchical porous ZSM-5-MCM-41 includes the following steps:

[0074] S31. A first aging treatment is performed on a first raw material mixture containing a first silicon source, a first alkali source, a first template agent and water to obtain seed crystals;

[0075] S32. A second aging treatment is performed on a second raw material mixture containing a second silicon source, an aluminum source, a second alkali source, a second template agent, and water to obtain a third raw material mixture;

[0076] S33. The seed crystals are added to the third raw material mixture to obtain a fourth raw material mixture;

[0077] S34. The fourth raw material mixture is subjected to hydrothermal crystallization treatment to obtain the zeolite molecular sieve.

[0078] In some preferred embodiments of the present invention, the first silicon source and the second silicon source may be the same or different, and each is independently selected from one or more of tetraethyl orthosilicate, silica sol, silica gel, water glass, fumed silica and liquid silica.

[0079] In some preferred embodiments of the present invention, the first alkali source and the second alkali source may be the same or different, and each is independently selected from one or more of sodium hydroxide, potassium hydroxide and rubidium hydroxide.

[0080] In some preferred embodiments of the present invention, the first template agent is selected from one or more of tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrabutylammonium bromide, tetraethylammonium bromide, tetrapropylammonium bromide, n-butylamine, butanediamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, hexamethylenediamine and the compound shown in formula (1);

[0081] C n H 2n+1 (CH3)3NBr Formula (1)

[0082] In equation (1), n ​​= 4, 6, 8, 10 or 12.

[0083] In some preferred embodiments of the present invention, the second template agent is selected from one or more of tetradecyltrimethylammonium bromide and hexadecyltrimethylammonium bromide.

[0084] In some preferred embodiments of the present invention, the aluminum source is selected from one or more of aluminum isopropoxide, sodium aluminate, and aluminum sulfate.

[0085] In step S1, the first alkali source, the first template agent and water can be mixed first, and then the first silicon source can be added to it.

[0086] According to the present invention, the mixing order of the various materials is not the key to the present invention. Those skilled in the art can obtain the first raw material mixture and the second raw material mixture described in the present invention by using conventional methods.

[0087] As an example only, the order in which the raw materials are mixed together may be as follows: first, dissolve the second alkali source and the second template agent in water and stir, then add the aluminum source and the second silicon source and stir and age, then add seed crystals to the mixture and stir to obtain the raw material mixture.

[0088] In some preferred embodiments of the present invention, in step S31, the molar ratio of the first alkali source (calculated as alkali metal oxide) to the first silicon source (calculated as SiO2) is (0.025 to 0.125):1.

[0089] In some preferred embodiments of the present invention, in step S31, the molar ratio of the first template agent to the first silicon source (based on SiO2) is (0.1 to 0.4):1.

[0090] In some preferred embodiments of the present invention, in step S31, the molar ratio of water to the first silicon source (calculated as SiO2) is (15-50):1.

[0091] In some preferred embodiments of the present invention, in step S32, the molar ratio of the aluminum source (calculated as Al2O3) to the second silicon source (calculated as SiO2) is (0.017 to 0.05):1.

[0092] In some preferred embodiments of the present invention, in step S32, the molar ratio of the second alkali source (calculated as alkali metal oxide) to the second silicon source (calculated as SiO2) is (0.05 to 0.3):1.

[0093] In some preferred embodiments of the present invention, in step S32, the molar ratio of the second template agent to the second silicon source (based on SiO2) is (0.008 to 0.025):1.

[0094] In some preferred embodiments of the present invention, in step S31, the molar ratio of water to the second silicon source (calculated as SiO2) is (20-50):1.

[0095] In some preferred embodiments of the present invention, in step S31, the conditions for the first aging treatment include: an aging temperature of 60°C to 110°C; and an aging time of 1 hour to 20 hours, preferably 10 hours to 20 hours.

[0096] In some preferred embodiments of the present invention, in step S32, the conditions for the second aging treatment include: an aging temperature of 60°C to 110°C; and an aging time of 1 hour to 30 hours, preferably 15 hours to 25 hours.

[0097] In some preferred embodiments of the present invention, in step S34, the conditions for the hydrothermal crystallization treatment include: a hydrothermal crystallization temperature of 120°C to 200°C; and a hydrothermal crystallization time of 8h to 72h.

[0098] According to the present invention, the preparation methods of the first catalyst component and the second catalyst component can employ methods well known to those skilled in the art. Exemplarily, the preparation methods of the first catalyst component and the second catalyst component can be as follows: mixing a solution containing the modified component source with a support source, followed by sequential drying and calcination, wherein the drying temperature is 60–150°C, preferably 80–120°C; the drying time is 2–24 hours, preferably 3–8 hours; the calcination temperature is 250–750°C, preferably 350–550°C; the calcination time is 2–12 hours, preferably 3–8 hours; the calcination atmosphere is not particularly required, and both oxidizing and inert atmospheres are acceptable, both yielding comparable technical effects. Oxidizing atmospheres include, but are not limited to, oxygen-containing atmospheres, with air atmospheres preferred from an economic perspective; inert atmospheres include, but are not limited to, at least one of nitrogen or inert gas atmospheres, where the inert gas can be nitrogen, helium, argon, etc. From an economic perspective, nitrogen is commonly chosen as the inert atmosphere. For comparability, air atmospheres are used in all embodiments of the present invention.

[0099] According to the present invention, the source of the modified component can be a soluble salt or soluble acid of the modifying element in the modified component. The NiO source can be a compound containing Ni, without particular limitation, such as, but not limited to, nickel nitrate, nickel acetate, nickel oxalate, etc. The MoO3 source can be a compound containing Mo, without particular limitation, such as, but not limited to, ammonium molybdate, ammonium heptamolybdate, etc. The WO3 source can be a compound containing W, without particular limitation, such as, but not limited to, ammonium tungstate, ammonium metatungstate, tungstic acid, etc. The P2O5 source can be a compound containing P, without particular limitation, such as, but not limited to, phosphoric acid, phosphorous acid, etc.

[0100] According to the present invention, the concentration of the modified component source in the solution containing the modified component source is not particularly limited, and those skilled in the art can determine the specific value according to the actual loading requirements and loading method.

[0101] To achieve the second objective mentioned above, the technical solution adopted by the present invention is as follows:

[0102] Application of a catalyst system according to any one of the above embodiments in the refining of catalytic cracking light cycle oil.

[0103] In some preferred embodiments of the invention, the application includes contacting the catalytic cracking light cycle oil with the catalyst system.

[0104] According to the present invention, under the action of the catalyst system, the polycyclic aromatic hydrocarbons in the catalytic cracking light cycle oil are hydrogenated and refined to produce monocyclic aromatic hydrocarbons.

[0105] In some preferred embodiments of the present invention, the catalytic cracking light cycle oil is contacted sequentially with the first catalyst component and the second catalyst component.

[0106] In some preferred embodiments of the invention, the contact occurs within the same reactor.

[0107] In some preferred embodiments of the present invention, the first catalyst component and the second catalyst component are configured to be in direct contact.

[0108] In some preferred embodiments of the present invention, the contact conditions include: an inlet temperature of 200°C to 350°C; a reaction pressure of 2.3 to 8.0 MPa; a hydrogen-to-oil volume ratio of (400 to 2000):1; and a liquid hourly space velocity of 0.2 to 2.8 h⁻¹. -1 .

[0109] According to the present invention, the catalyst system can be pre-sulfurized before the contact is performed. Pre-sulfurization is a conventional operation in the art, and the present invention does not intend to impose excessive limitations on it. Exemplarily, pre-sulfurization is performed using the following steps: cyclohexane containing 100–10000 ppm CS2 is used as the sulfiding oil, and the mixture is subjected to a space velocity of 0.2–8 h⁻¹. -1 The hydrogen-to-oil volume ratio is 100–2500:1, and the catalyst is pre-sulfurized at an operating pressure of 1.0–10.0 MPa.

[0110] In the above pre-sulfurization, the concentration of CS2 in the sulfurized oil is preferably 500 to 5000 ppm, such as, but not limited to, 500 ppm, 1000 ppm, 1500 ppm, 2000 ppm, 2500 ppm, 3000 ppm, 3500 ppm, 4000 ppm, 4500 ppm, 5000 ppm, etc. More preferably, it is 1000 ppm, 1500 ppm, 2000 ppm, 2500 ppm, 3000 ppm, 3500 ppm.

[0111] However, for comparison, the catalyst in the specific embodiment of the present invention is sulfided using the following steps: Under a system pressure of 0.5 MPa, N2 is introduced at a rate of 30°C / h to raise the temperature to 170°C, with an N2 flow rate of 850 ml / min. N2 is then stopped, and H2 and sulfided oil (containing 2500 ppm CS2) are introduced. The system pressure is raised to 2.5 MPa, the hydrogen-to-oil volume ratio is 300, and the sulfided oil volume hourly space velocity is 4.0 h⁻¹. -1 Simultaneously, the temperature is increased to 230℃ at a rate of 20℃ / h for 3 hours, held at this temperature for 4 hours, then increased to 320℃ at a rate of 20℃ / h for 4.5 hours, and held at this temperature for 24 hours, at which point the catalyst sulfidation is complete. With sulfiding oil flowing through, the bed inlet temperature is lowered to the required reaction temperature.

[0112] According to the present invention, "catalytic cracking light cycle oil (LCO)" is a feedstock in the petroleum catalytic cracking (FCC) process, and its composition, by mass percentage, includes: a total aromatic hydrocarbon content of 60% to 90%, with the remainder being alkanes, cycloalkanes, etc. Among the aromatic hydrocarbons, naphthalene-based bicyclic aromatic hydrocarbons account for 35% to 75%, while monocyclic and tricyclic aromatic hydrocarbons each account for 12.5% ​​to 30.0%. The LCO has a sulfur content of 0.2 to 1.5 wt%, a nitrogen content of 100 to 1000 ppm, and a cetane number of 15 to 25.

[0113] The beneficial effects of this invention are at least as follows: When using the catalyst system of this invention for catalytic cracking light cycle oil refining, the obtained product exhibits a monocyclic aromatic hydrocarbon selectivity of 89%, a nitrogen content of less than 10 ppm, and a cracked gas composition of CH4, C2H6, C3H8, and C4H2O. 10 With a total content of less than 500 ppm, the product can be directly used as a blending component for gasoline and diesel or as a high-quality raw material for the production of BTX, which greatly enhances the added value of the product and achieves good technical results. Attached Figure Description

[0114] Figure 1 This is the PY-IR spectrum of the lower bed carrier in Example 1. Detailed Implementation

[0115] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited to the following description.

[0116] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0117] In this invention, unless otherwise specified, "%" refers to the percentage content by mass.

[0118]

Example 1

[0119] 1. Preparation of layered hierarchical porous ZSM-5-MCM-41 molecular sieve

[0120] a) Seed preparation: Sodium hydroxide, tetrapropylammonium hydroxide (TPAOH) and water are mixed and stirred for 2 hours. After being fully dissolved, fumed silica is added and stirred for 3 hours. The mixture is then aged at 100°C for 16 hours.

[0121] b) Dissolve sodium hydroxide and cetyltrimethylammonium bromide (CTAB) in water and stir for 2 hours. Then add sodium aluminate and fumed silica in sequence and stir for 2 hours. After aging at 100°C for 21 hours, add seed crystals a) and stir for 3 hours.

[0122] c) Perform hydrothermal crystallization of b) at 180°C for 48 hours;

[0123] The product was rapidly cooled, filtered, washed with water until the pH value reached 7, and dried at 120℃ for 12 hours to obtain layered multi-level porous ZSM-5-MCM-41 molecular sieve raw powder. The molar ratios of the raw materials in reaction mixture b) were: SiO2 / Al2O3 = 30, H2O / SiO2 = 30, Na2O / SiO2 = 0.11, CTAB / TPAOH = 2, CTAB / SiO2 = 0.13.

[0124] The prepared layered ZSM-5-MCM-41(21) nanomolecular sieve raw powder was processed at 0.2 mol·L⁻¹ -1 The sample was soaked in ammonium nitrate solution with a solid-liquid ratio of 1:15, heated at 90°C and stirred for 2 hours, then filtered and washed. This process was repeated three times. The sample was dried at 120°C for 6 hours and finally calcined at 550°C for 5 hours to obtain hydrogen-form layered ZSM-5-MCM-41(21) nanomolecular sieve powder.

[0125] 2. Preparation of the carrier

[0126] Upper Bed Carrier: 400g of Al2O3 raw powder with a particle size of 0.8 micrometers and 12g of guar gum powder were mixed evenly in a kneader. 380g of an aqueous solution containing nitric acid and ammonium bicarbonate was added, with the nitric acid content being 1.8% and the ammonium bicarbonate content being 2.2% by mass. The mixture was kneaded thoroughly at room temperature for 60 minutes. The mixture was then transferred to an extruder and extruded to obtain a clover-shaped carrier with a diameter of 1.5mm and a length of 3.0mm. The carrier was dried at room temperature for 24 hours, then dried in an oven at 120℃ for 6 hours, and finally calcined in a muffle furnace at 550℃ for 3 hours.

[0127] Lower bed support: 360 g of Al2O3 powder containing 8% SiO2 (particle size 0.8 μm), 40 g of hydrogen-form layered hierarchical porous HZSM-5-MCM-41 powder, 16 g of guar gum powder, and 2.4 g of hydroxymethyl cellulose were thoroughly mixed. 360 g of an aqueous solution containing nitric acid and boric acid (2% by mass) and 1% by mass of boric acid were added. The mixture was kneaded in a kneader to form a plastic body, then shaped in an extruder to obtain a clover-shaped support with a diameter of 1.5 mm and a length of 3.0 mm. The support was dried at room temperature for 24 hours, dried in an oven at 120 °C for 6 hours, and calcined in a muffle furnace at 550 °C for 3 hours. The PY-IR spectrum of the prepared support is shown below. Figure 1 As shown in Table 1, the parameters of the lower support are as follows: the ratio of Brønsted acid to Lewis acid at 300℃ and 400℃ is shown in Table 1; the ratio of medium strong acid to total acid is 0.75; and the ratio of mesopore volume to micropore volume is 13.

[0128] 3. Catalyst Preparation

[0129] Take 1L of the first support Al2O3 support and mix it with 0.75L of a mixed solution of nickel acetate and ammonium molybdate (containing 80g NiO and 200g MoO3). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0130] The first catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0131] Take 1L of the second support Al2O3-SiO2-(hydrogen-type layered hierarchical porous HZSM-5-MCM-41) multi-element composite support and mix it with 0.75L of a mixed solution of nickel acetate and ammonium molybdate (containing 80g NiO and 200g MoO3). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0132] The second catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0133] 4. Catalyst loading

[0134] After filling the bottom of the reactor with ∮3 ceramic balls, the second catalyst and the first catalyst are added in sequence, with the volume ratio of the first catalyst to the second catalyst being 5:5. The material flows in from the top and out from the bottom.

[0135] 5. Catalyst sulfidation

[0136] At a system pressure of 0.5 MPa, N2 was introduced at a rate of 30 °C / h to raise the temperature to 170 °C. The N2 flow rate was 850 ml / min. Then, N2 was stopped, and H2 and sulfurized oil (containing 2500 ppm CS2) were introduced. The system pressure rose to 2.5 MPa, the hydrogen-to-oil volume ratio was 300, and the sulfurized oil volume hourly space velocity was 4.0 h⁻¹. -1 Simultaneously, the temperature is increased to 230℃ at a rate of 20℃ / h for 3 hours, held at this temperature for 4 hours, then increased to 320℃ at a rate of 20℃ / h for 4.5 hours, and held at this temperature for 24 hours, at which point the catalyst sulfidation is complete. With sulfiding oil flowing through, the bed inlet temperature is lowered to the required reaction temperature.

[0137] 6. Catalyst Evaluation

[0138] Catalyst evaluation conditions: inlet temperature 270℃, reaction pressure 6.0MPa, H2 / Oil molar ratio 1200, and feed liquid hourly space velocity 0.8h. -1 Catalyst evaluation was conducted.

[0139] For ease of comparison, the types and contents of the modifying elements in the second catalyst, as well as the evaluation results of the catalyst, are listed in Table 2. Additionally, the physical properties of the catalyst supports used in the upper and lower beds are listed in Table 3.

[0140]

Example 2

[0141] 1. Preparation of layered hierarchical porous ZSM-5-MCM-41 molecular sieve

[0142] The preparation was carried out in the same manner as in Example 1.

[0143] 2. Preparation of the carrier

[0144] Upper bed carrier: Prepared in the same manner as in Example 1.

[0145] The subbed carrier was prepared in the same manner as in Example 1.

[0146] 3. Catalyst Preparation

[0147] Take 1 L of the first carrier Al2O3 and mix it with 0.75 L of a mixed solution of nickel acetate and ammonium molybdate (containing 80 g of NiO and 200 g of MoO3). Dry at 110 °C for 6 hours and calcine at 450 °C for 4 hours.

[0148] The first catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0149] Take 1L of the second support Al2O3-SiO2-(hydrogen-type layered hierarchical porous HZSM-5-MCM-41) multi-element composite support and mix it with 0.75L of a mixed solution of nickel acetate and ammonium metatungstate (containing 80g NiO and 200g WO3). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0150] The second catalyst contains 80 g / L NiO and 200 g / L WO3.

[0151] 4. Catalyst loading

[0152] The filling and feeding were carried out in the same manner as in Example 1.

[0153] 5. Catalyst sulfidation

[0154] Vulcanization was carried out in the same manner as in Example 1.

[0155] 6. Catalyst Evaluation

[0156] The evaluation was conducted in the same manner as in Example 1.

[0157]

Example 3

[0158] 1. Preparation of layered hierarchical porous ZSM-5-MCM-41 molecular sieve

[0159] The preparation was carried out in the same manner as in Example 1.

[0160] 2. Preparation of the carrier

[0161] Upper bed carrier: Prepared in the same manner as in Example 1.

[0162] The subbed carrier was prepared in the same manner as in Example 1.

[0163] 3. Catalyst Preparation

[0164] Take 1 L of the first carrier Al2O3 and mix it with 0.75 L of a mixed solution of nickel acetate and ammonium molybdate (containing 80 g of NiO and 200 g of MoO3). Dry it at 110 °C for 6 hours and calcine it at 450 °C for 4 hours.

[0165] The first catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0166] Take 1L of the second support Al2O3-SiO2-(hydrogen-type layered hierarchical porous HZSM-5-MCM-41) multi-element composite support and mix it with 0.75L of a mixed solution of nickel acetate, ammonium molybdate and phosphoric acid (containing 70g NiO, 200g MoO3 and 10g P2O5). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0167] The second catalyst contains 70 g / L NiO, 200 g / L MoO3, and 10 g / L P2O5.

[0168] 4. Catalyst loading

[0169] The filling and feeding were carried out in the same manner as in Example 1.

[0170] 5. Catalyst sulfidation

[0171] Vulcanization was carried out in the same manner as in Example 1.

[0172] 6. Catalyst Evaluation

[0173] The evaluation was conducted in the same manner as in Example 1.

[0174]

Example 4

[0175] 1. Preparation of layered hierarchical porous ZSM-5-MCM-41 molecular sieve

[0176] The preparation was carried out in the same manner as in Example 1.

[0177] 2. Preparation of the carrier

[0178] Upper bed carrier: Prepared in the same manner as in Example 1.

[0179] The subbed carrier was prepared in the same manner as in Example 1.

[0180] 3. Catalyst Preparation

[0181] Take 1 L of the first carrier Al2O3 and mix it with 0.75 L of a mixed solution of nickel acetate and ammonium molybdate (containing 80 g of NiO and 200 g of MoO3). Dry at 110 °C for 6 hours and calcine at 450 °C for 4 hours.

[0182] The first catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0183] Take 1L of the second support Al2O3-SiO2-(hydrogen-type layered hierarchical porous HZSM-5-MCM-41) multi-element composite support and mix it with 0.75L of a mixed solution of nickel acetate, ammonium molybdate and ammonium metatungstate (containing 55g NiO, 80g MoO3 and 145g WO3). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0184] The second catalyst contains 55 g / L NiO, 80 g / L MoO3, and 145 g / L WO3.

[0185] 4. Catalyst loading

[0186] The filling and feeding were carried out in the same manner as in Example 1.

[0187] 5. Catalyst sulfidation

[0188] Vulcanization was carried out in the same manner as in Example 1.

[0189] 6. Catalyst Evaluation

[0190] The evaluation was conducted in the same manner as in Example 1.

[0191]

Example 5

[0192] 1. Preparation of layered hierarchical porous ZSM-5-MCM-41 molecular sieve

[0193] The preparation was carried out in the same manner as in Example 1.

[0194] 2. Preparation of the carrier

[0195] Upper bed carrier: Prepared in the same manner as in Example 1.

[0196] The subbed carrier was prepared in the same manner as in Example 1.

[0197] 3. Catalyst Preparation

[0198] Take 1L of the first carrier Al2O3 and mix it with 0.75L of a mixed solution of nickel acetate and ammonium molybdate (containing 80g of NiO and 200g of MoO3). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0199] The first catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0200] Take 1L of the second support Al2O3-SiO2-(hydrogen-type layered hierarchical porous HZSM-5-MCM-41) multi-element composite support and mix it with 0.75L of a mixed solution of nickel acetate, ammonium molybdate, ammonium metatungstate and phosphoric acid (containing 50g NiO, 80g MoO3, 145g WO3 and 5g P2O5). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0201] The second catalyst contains 50 g / L NiO, 80 g / L MoO3, 145 g / L WO3, and 5 g / L P2O5.

[0202] 4. Catalyst loading

[0203] The filling and feeding were carried out in the same manner as in Example 1.

[0204] 5. Catalyst sulfidation

[0205] Vulcanization was carried out in the same manner as in Example 1.

[0206] 6. Catalyst Evaluation

[0207] The evaluation was conducted in the same manner as in Example 1.

[0208]

Example 6

[0209] 1. Preparation of Beta molecular sieves

[0210] a) Seed preparation: Sodium hydroxide, tetraethylammonium hydroxide (TEAOH) and water are mixed and stirred for 2 hours. After being fully dissolved, fumed silica is added and stirred for 3 hours. The mixture is then aged at 100°C for 30 hours.

[0211] b) Dissolve sodium hydroxide and tetraethylammonium hydroxide (TEAOH) in water and stir for 2 hours. Then add sodium aluminate and 40% silica sol in sequence and stir for 2 hours. After aging at 100°C for 8 hours, add seed crystals (a) and stir for 3 hours.

[0212] c) Perform hydrothermal crystallization of b) at 180°C for 72 hours;

[0213] The product was rapidly cooled, filtered, washed with water until the pH value reached 7, and dried at 120℃ for 12 hours to obtain Beta molecular sieve raw powder. The molar ratios of the raw materials in reaction mixture b) were: SiO2 / Al2O3 = 30, H2O / SiO2 = 30, Na2O / SiO2 = 0.11, TEAOH / SiO2 = 0.13.

[0214] The obtained Beta molecular sieve powder was prepared at 0.2 mol·L⁻¹ -1 The sample was soaked in ammonium nitrate solution with a solid-liquid ratio of 1:15, heated at 90°C and stirred for 2 hours, then filtered and washed. This process was repeated three times. The resulting sample was dried at 120°C for 6 hours and finally calcined at 550°C for 5 hours to obtain hydrogen-form Beta molecular sieve powder.

[0215] 2. Preparation of the carrier

[0216] Upper bed carrier: Prepared in the same manner as in Example 1.

[0217] Lower bed carrier: 360 g of Al2O3 powder containing 8% SiO2 (particle size 0.8 μm), 40 g of hydrogen-form Beta powder, 16 g of guar gum powder, and 2.4 g of hydroxymethyl cellulose were thoroughly mixed. 380 g of an aqueous solution containing 2% nitric acid and 1% boric acid was added. The mixture was kneaded in a kneader to form a plastic body, and then shaped in an extruder to obtain a clover-shaped carrier with a diameter of 1.5 mm and a length of 3.0 mm. The carrier was dried at room temperature for 24 hours, dried in an oven at 120°C for 6 hours, and calcined in a muffle furnace at 550°C for 3 hours.

[0218] 3. Catalyst Preparation

[0219] Take 1L of the first carrier Al2O3 and mix it with 0.75L of a mixed solution of nickel acetate and ammonium molybdate (containing 80g of NiO and 200g of MoO3). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0220] The first catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0221] Take 1L of the second support Al2O3-SiO2-Hbeta multi-component composite support and mix it with 0.75L of a mixed solution of nickel acetate, ammonium molybdate, ammonium metatungstate and phosphoric acid (containing 50g NiO, 80g MoO3, 145g WO3 and 5g P2O5). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0222] The second catalyst contains 50 g / L NiO, 80 g / L MoO3, 145 g / L WO3, and 5 g / L P2O5.

[0223] 4. Catalyst loading

[0224] The filling and feeding were carried out in the same manner as in Example 1.

[0225] 5. Catalyst sulfidation

[0226] Vulcanization was carried out in the same manner as in Example 1.

[0227] 6. Catalyst Evaluation

[0228] The evaluation was conducted in the same manner as in Example 1.

[0229]

Example 7

[0230] 1. Preparation of ZSM-5 molecular sieve

[0231] a) Seed preparation: Sodium hydroxide, tetrapropylammonium hydroxide (TPAOH) and water are mixed and stirred for 2 hours. After being fully dissolved, fumed silica is added and stirred for 3 hours. The mixture is then aged at 100°C for 24 hours.

[0232] b) Dissolve sodium hydroxide and tetrapropylammonium hydroxide (TPAOH) in water and stir for 2 hours. Then add sodium aluminate and 40% silica sol in sequence and stir for 2 hours. After aging at 100°C for 12 hours, add seed crystals (a) and stir for 3 hours.

[0233] c) Perform hydrothermal crystallization of b) at 180°C for 64 hours;

[0234] The product was rapidly cooled, filtered, washed with water until the pH value reached 7, and dried at 120℃ for 12 hours to obtain Beta molecular sieve raw powder. The molar ratios of the raw materials in reaction mixture b) were: SiO2 / Al2O3 = 30, H2O / SiO2 = 30, Na2O / SiO2 = 0.11, TPAOH / SiO2 = 0.13.

[0235] The prepared ZSM-5 molecular sieve powder was processed at 0.2 mol·L⁻¹ -1 The sample was soaked in ammonium nitrate solution with a solid-liquid ratio of 1:15, heated at 90°C and stirred for 2 hours, then filtered and washed. This process was repeated three times. The resulting sample was dried at 120°C for 6 hours and finally calcined at 550°C for 5 hours to obtain hydrogen-form ZSM-5 molecular sieve powder.

[0236] 2. Preparation of the carrier

[0237] Upper bed carrier: Prepared in the same manner as in Example 1.

[0238] Lower bed carrier: 360 g of Al2O3 powder containing 8% SiO2 (particle size 0.8 μm), 40 g of hydrogen-form ZSM-5 powder, 16 g of guar gum powder, and 2.4 g of hydroxymethyl cellulose were thoroughly mixed. 400 g of an aqueous solution containing nitric acid and boric acid (2% by mass and 1% by mass) was added. The mixture was kneaded in a kneader to form a plastic body, and then shaped in an extruder to obtain a clover-shaped carrier with a diameter of 1.5 mm and a length of 3.0 mm. The carrier was dried at room temperature for 24 hours, dried in an oven at 120°C for 6 hours, and calcined in a muffle furnace at 550°C for 3 hours.

[0239] 3. Catalyst Preparation

[0240] Take 1L of the first carrier Al2O3 and mix it with 0.75L of a mixed solution of nickel acetate and ammonium molybdate (containing 80g of NiO and 200g of MoO3). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0241] The first catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0242] Take 1L of the second support Al2O3-SiO2-HZSM-5 multi-component composite support and mix it with 0.75L of a mixed solution of nickel acetate, ammonium molybdate, ammonium metatungstate and phosphoric acid (containing 50g NiO, 80g MoO3, 145g WO3 and 5g P2O5). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0243] The second catalyst contains 50 g / L NiO, 80 g / L MoO3, 145 g / L WO3, and 5 g / L P2O5.

[0244] 4. Catalyst loading

[0245] The filling and feeding were carried out in the same manner as in Example 1.

[0246] 5. Catalyst sulfidation

[0247] Vulcanization was carried out in the same manner as in Example 1.

[0248] 6. Catalyst Evaluation

[0249] The evaluation was conducted in the same manner as in Example 1.

[0250]

Example 8

[0251] 1. Preparation of Mor molecular sieves

[0252] a) Seed preparation: Sodium hydroxide, ethanolamine (MEA) and water are mixed and stirred for 2 hours. After being fully dissolved, fumed silica is added and stirred for 3 hours. The mixture is then aged at 100°C for 36 hours.

[0253] b) Dissolve sodium hydroxide and ethanolamine (MEA) in water and stir for 2 hours. Then add sodium aluminate and 40% silica sol in sequence and stir for 2 hours. After aging at 100°C for 12 hours, add seed crystals (a) and stir for 3 hours.

[0254] c) Perform hydrothermal crystallization of b) at 180°C for 52 hours;

[0255] The product was rapidly cooled, filtered, washed with water until the pH value reached 7, and dried at 120℃ for 12 hours to obtain Mor molecular sieve raw powder. The molar ratios of the raw materials in reaction mixture b) were: SiO2 / Al2O3 = 30, H2O / SiO2 = 30, Na2O / SiO2 = 0.11, MEA / SiO2 = 0.13.

[0256] The prepared Mor molecular sieve powder was then subjected to a concentration of 0.2 mol·L⁻¹. -1 The sample was soaked in ammonium nitrate solution with a solid-liquid ratio of 1:15, heated at 90°C and stirred for 2 hours, then filtered and washed. This process was repeated three times. The resulting sample was dried at 120°C for 6 hours and finally calcined at 550°C for 5 hours to obtain hydrogen-form Mor sieve powder.

[0257] 2. Preparation of the carrier

[0258] Upper bed carrier: Prepared in the same manner as in Example 1.

[0259] Lower bed carrier: 360 g of Al2O3 powder containing 8% SiO2 (particle size 0.8 μm), 40 g of hydrogen-form Mor powder, 16 g of guar gum powder, and 2.4 g of hydroxymethyl cellulose were thoroughly mixed. 400 g of an aqueous solution containing nitric acid and boric acid (2% by mass) and 1% by mass of boric acid were added. The mixture was kneaded in a kneader to form a plastic body, and then shaped in an extruder to obtain a clover-shaped carrier with a diameter of 1.5 mm and a length of 3.0 mm. The carrier was dried at room temperature for 24 hours, dried in an oven at 120°C for 6 hours, and calcined in a muffle furnace at 550°C for 3 hours.

[0260] 3. Catalyst Preparation

[0261] Take 1 L of the first carrier Al2O3 and mix it with 0.75 L of a mixed solution of nickel acetate and ammonium molybdate (containing 80 g of NiO and 200 g of MoO3). Dry at 110 °C for 6 hours and calcine at 450 °C for 4 hours.

[0262] The first catalyst contains 80 g / L NiO and 200 g / L MoO3.

[0263] Take 1L of the second support Al2O3-SiO2-HMor multi-component composite support and mix it with 0.75L of a mixed solution of nickel acetate, ammonium molybdate, ammonium metatungstate and phosphoric acid (containing 50g NiO, 80g MoO3, 145g WO3 and 5g P2O5). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0264] The catalyst contains 50 g / L NiO, 80 g / L MoO3, 145 g / L WO3, and 5 g / L P2O5.

[0265] 4. Catalyst loading

[0266] The filling and feeding were carried out in the same manner as in Example 1.

[0267] 5. Catalyst sulfidation

[0268] Vulcanization was carried out in the same manner as in Example 1.

[0269] 6. Catalyst Evaluation

[0270] The evaluation was conducted in the same manner as in Example 1.

[0271] Comparative Example 1

[0272] 1. Preparation of Al2O3 support

[0273] The upper bed carrier was prepared in the same manner as in Example 1.

[0274] 2. Catalyst Preparation

[0275] Take 1L of the molded Al2O3 support and mix it with 0.75L of a mixed solution of nickel acetate, ammonium molybdate, ammonium metatungstate, and phosphoric acid (NiO 50g / L, MoO3 80g / L, WO3 145g / L, P2O5 5g / L). Dry at 110℃ for 6 hours and calcine at 450℃ for 4 hours.

[0276] The catalyst contains 50 g / L NiO, 80 g / L MoO3, 145 g / L WO3, and 5 g / L P2O5.

[0277] 3. Catalyst loading

[0278] After filling the bottom of the reactor with ∮3 ceramic balls, the same volume of catalyst prepared in step 2 as in Example 1 is then filled in, with the material flowing in from the top and out from the bottom.

[0279] 4. Catalyst sulfidation

[0280] Vulcanization was carried out in the same manner as in Example 1.

[0281] 5. Catalyst Evaluation

[0282] The evaluation was conducted in the same manner as in Example 1.

[0283] Table 1

[0284] Example 300℃ 400℃ 1 3 2.2 2 3 2.2 3 3 2.2 4 3 2.2 5 3 2.2 6 4.9 6.1 7 5.6 7.3 8 4.3 6.3

[0285] Table 2

[0286]

[0287]

[0288] Table 3

[0289]

[0290] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on 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 terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A catalyst system for refining light cycle oil from catalytic cracking, comprising: First catalyst component and second catalyst component The first catalyst component includes a first support and a first modifying component. The first support is Al2O3, and the first modifying component is selected from at least two of NiO, MoO3, WO3 and P2O5, and the first modifying component includes NiO. The second catalyst component includes a second support and a second modifying component. The second support is an Al2O3-SiO2-molecular sieve multi-component composite support. The second modifying component is selected from at least two of NiO, MoO3, WO3 and P2O5, and the second modifying component includes NiO. In the Al2O3-SiO2-molecular sieve multi-component composite support, the mass percentage of Al2O3 is 72%~97%, the mass percentage of SiO2 is 2%~10%, and the mass percentage of molecular sieve is 1%~18%; the molecular sieve is selected from at least one of HZSM-5, HMor, Hβ, and layered hierarchical porous HZSM-5-MCM-41. The catalytic cracking light cycle oil is contacted sequentially with the first catalyst component and the second catalyst component.

2. The catalyst system according to claim 1, characterized in that, The first carrier is γ-Al2O3; and / or The first modifying component is selected from at least two of NiO, MoO3, and P2O5, and the first modifying component includes NiO; and / or The second modifying component is selected from at least three of NiO, MoO3, WO3, and P2O5, and the second modifying component includes NiO; and / or The volume ratio of the first catalyst component to the second catalyst component is (1~8):(2~9); and / or In the Al2O3-SiO2-molecular sieve multi-component composite support, the Al2O3 is γ-Al2O3; and / or The molecular sieve is a layered, hierarchical porous HZSM-5-MCM-41.

3. The catalyst system according to claim 2, characterized in that, The first modified component includes NiO and MoO3; and / or The second modifying component includes NiO, MoO3, WO3, and P2O5; and / or The volume ratio of the first catalyst component to the second catalyst component is (2~7):(3~8); and / or The layered hierarchical porous HZSM-5-MCM-41 has at least one of the following characteristics: 1) The ratio of Brønsted acid to Lewis acid in the layered hierarchical porous ZSM-5-MCM-41 is (2-4):1 at 400℃ and (2-5):1 at 300℃. 2) In the layered hierarchical porous ZSM-5-MCM-41, the ratio of medium-strong acid content to total acid content is (0.55~0.85):1; 3) The mesopore volume to micropore volume ratio of the layered hierarchical porous ZSM-5-MCM-41 is 8–15, the average pore size is 5–10 nm, and the pore volume is 0.5–0.8 cm³. 3 / g, specific surface area greater than 300 m² 2 ·g -1 ; 4) The molar ratio of silica to alumina in the layered hierarchical porous ZSM-5-MCM-41 is (20~200):

1.

4. The catalyst system according to claim 3, characterized in that, The volume ratio of the first catalyst component to the second catalyst component is (3~5):(5~7); and / or In the layered hierarchical porous ZSM-5-MCM-41, the ratio of medium-strong acid content to total acid content is (0.6–0.8):1; and / or The molar ratio of silica to aluminum oxide in the layered hierarchical porous ZSM-5-MCM-41 is (20-60):

1.

5. The catalyst system according to any one of claims 1-4, characterized in that, The first catalyst component is disposed in the upper layer of the catalyst bed, and the second catalyst component is disposed in the lower layer of the catalyst bed.

6. The catalyst system according to claim 5, characterized in that, The first catalyst component and the second catalyst component are configured to be in direct contact in the same reactor.

7. The catalyst system according to any one of claims 1-4, characterized in that, In the first catalyst component, based on the total weight of the first catalyst component, the mass percentage of the first support is 50%–80%, and the mass percentage of the first modified component is 20%–50%; and / or In the second catalyst component, based on the total weight of the second catalyst component, the mass percentage of the second support is 50% to 80%, and the mass percentage of the second modified component is 20% to 50%.

8. The catalyst system according to claim 7, characterized in that, In the first catalyst component, based on the total weight of the first catalyst component, the mass percentage of the first modified component is 20% to 30%; and / or In the first catalyst component, based on the total weight of the first catalyst component, the mass percentage of NiO is 3%–10%, the mass percentage of MoO3 is 5%–25%, the mass percentage of WO3 is 12%–16%, and the mass percentage of P2O5 is 0.1%–1%; and / or In the second catalyst component, based on the total weight of the second catalyst component, the mass percentage of the second support is 55% to 70%; and / or In the second catalyst component, based on the total weight of the second catalyst component, the mass percentage of NiO is 3% to 8%, the mass percentage of MoO3 is 5% to 10%, the mass percentage of WO3 is 12% to 30%, and the mass percentage of P2O5 is 0.1% to 1%.

9. The catalyst system according to any one of claims 1-4, characterized in that, The specific surface area of ​​the first carrier is 180 m². 2 / g~320 m 2 / g, with an average pore size of 7–14 nm and a pore volume of 0.6–0.88 cm³. 3 / g; and / or The specific surface area of ​​the second carrier is 250 m². 2 / g~450 m 2 / g, with an average pore size of 5–13 nm and a pore volume of 0.50–0.85 cm³. 3 / g.

10. The catalyst system according to claim 9, characterized in that, The specific surface area of ​​the first carrier is 190 m². 2 / g~250 m 2 / g, with an average pore size of 8–12 nm and a pore volume of 0.7–0.85 cm³. 3 / g; and / or The specific surface area of ​​the second carrier is 280 m². 2 / g~380 m 2 / g, with an average pore size of 5–10 nm and a pore volume of 0.55–0.75 cm³. 3 / g.

11. The catalyst system according to any one of claims 1-4, characterized in that, The preparation method of the first carrier includes the following steps: S11. Mix Al2O3 raw powder and the first additive to obtain the first mixture; S12. Mix the first mixture and the first molding aid to obtain a second mixture; S13. The second mixture is subjected to molding treatment to obtain the first catalyst precursor; S14. The first catalyst precursor is dried and calcined sequentially to obtain the first support.

12. The catalyst system according to claim 11, characterized in that, In step S11, the average particle size of the Al2O3 raw powder is 0.1–2 micrometers; the first auxiliary agent is selected from at least one of guar gum powder and hydroxymethyl cellulose; and / or In step S12, the first molding aid is an aqueous solution containing nitric acid and / or ammonium bicarbonate; and / or In step S14, the calcination conditions include: a temperature of 450℃ to 650℃ and a time of 1h to 12h.

13. The catalyst system according to claim 12, characterized in that, In step S12, the mass percentage of nitric acid is 1.2% to 3.0%, and the mass percentage of ammonium bicarbonate is 1% to 5%. and / or In step S14, the calcination conditions include: a temperature of 500℃~600℃ and a time of 2h~5h.

14. The catalyst system according to claim 13, characterized in that, In step S12, the mass percentage of nitric acid is 1.5% to 2.5%, and the mass percentage of ammonium bicarbonate is 1% to 2.5%.

15. The catalyst system according to any one of claims 1-4, characterized in that, The preparation method of the second carrier includes the following steps: S21. Mix Al2O3 powder containing SiO2, molecular sieve, and second auxiliary agent to obtain mixture A; S22. Mix the mixture A and the second molding aid to obtain mixture B; S23. The mixture B is subjected to molding treatment to obtain a second catalyst precursor; S24. The second catalyst precursor is dried and calcined sequentially to obtain the second support.

16. The catalyst system according to claim 15, characterized in that, In step S21, the mass percentage of SiO2 in the Al2O3 powder containing SiO2 is 1% to 9%; the particle size of the Al2O3 powder containing SiO2 is 0.1 to 3 micrometers; the second additive is selected from at least one of guar gum powder, hydroxymethyl cellulose, carbon black, starch, and carbon fiber; and / or In step S22, the second molding aid is an aqueous solution containing nitric acid and / or boric acid and / or phosphoric acid; and / or In step S24, the calcination conditions include: a temperature of 450℃ to 650℃ and a time of 1h to 12h.

17. The catalyst system according to claim 16, characterized in that, In step S22, the mass percentage of nitric acid is 1%~5%, the mass percentage of boric acid is 1%~5%, and the mass percentage of phosphoric acid is 1%~5%. and / or In step S24, the calcination conditions include: a temperature of 500℃~600℃ and a time of 2h~6h.

18. The catalyst system according to claim 3 or 4, characterized in that, The preparation method of layered hierarchical porous ZSM-5-MCM-41 includes the following steps: S31. A first aging treatment is performed on a first raw material mixture containing a first silicon source, a first alkali source, a first template agent and water to obtain seed crystals; S32. A second aging treatment is performed on a second raw material mixture containing a second silicon source, an aluminum source, a second alkali source, a second template agent, and water to obtain a third raw material mixture; S33. The seed crystals are added to the third raw material mixture to obtain a fourth raw material mixture; S34. The fourth raw material mixture is subjected to hydrothermal crystallization treatment to obtain layered multi-level porous ZSM-5-MCM-41.

19. The catalyst system according to claim 18, characterized in that, The first silicon source and the second silicon source may be the same or different, and each is independently selected from one or more of tetraethyl orthosilicate, silica sol, silica gel, water glass, fumed silica, and liquid silica; and / or The first alkali source and the second alkali source may be the same or different, and each is independently selected from one or more of sodium hydroxide, potassium hydroxide, and rubidium hydroxide; and / or The first template agent is selected from one or more of the following: tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrabutylammonium bromide, tetraethylammonium bromide, tetrapropylammonium bromide, n-butylamine, butanediamine, triethylamine, ethanolamine, diethanolamine, triethanolamine, hexamethylenediamine, and the compound shown in formula (1); C n H 2n+1 (CH3)3NBr formula (1) In equation (1), n ​​= 4, 6, 8, 10 or 12; and / or The second template agent is selected from one or more of tetradecyltrimethylammonium bromide and hexadecyltrimethylammonium bromide; and / or The aluminum source is selected from one or more of aluminum isopropoxide, sodium aluminate, and aluminum sulfate.

20. The catalyst system according to claim 19, characterized in that, In step S31, The molar ratio of the first alkali source (calculated as alkali metal oxide) to the first silicon source (calculated as SiO2) is (0.025~0.125):1; and / or The molar ratio of the first template agent to the first silicon source (based on SiO2) is (0.1~0.4):1; and / or The molar ratio of water to the first silicon source (based on SiO2) is (15~50):1; and / or In step S32, The molar ratio of the aluminum source (calculated as Al2O3) to the second silicon source (calculated as SiO2) is (0.017~0.05):1; and / or The molar ratio of the second alkali source (calculated as alkali metal oxide) to the second silicon source (calculated as SiO2) is (0.05~0.3):1; and / or The molar ratio of the second template agent to the second silicon source (based on SiO2) is (0.008~0.025):1; and / or The molar ratio of water to the second silicon source (calculated as SiO2) is (20~50):1; and / or In step S31, the conditions for the first aging treatment include: an aging temperature of 60℃~110℃; an aging time of 1h~20h; and / or In step S32, the conditions for the second aging treatment include: an aging temperature of 60℃~110℃; an aging time of 1h~30h; and / or In step S34, the conditions for the hydrothermal crystallization treatment include: a hydrothermal crystallization temperature of 120℃~200℃ and a hydrothermal crystallization time of 8h~72h.

21. The catalyst system according to claim 20, characterized in that, In step S31, the conditions for the first aging treatment include: an aging time of 10h to 20h; and / or In step S32, the conditions for the second aging treatment include an aging time of 15h to 25h.

22. The application of any one of the catalyst systems of claims 1-21 in the refining of catalytic cracking light cycle oil, wherein the catalytic cracking light cycle oil is brought into contact with the catalyst system.

23. The application according to claim 22, characterized in that, The contact conditions include: inlet temperature of 200℃~350℃; reaction pressure of 2.3~8.0MPa; hydrogen-to-oil volume ratio of (400~2000):1; and liquid hourly space velocity of 0.2~2.8 h⁻¹. -1 .

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