A chemical hydrocracking catalyst, a preparation method and application thereof

Abstract

The present application relates to a kind of active improved chemical type hydrocracking catalyst and its preparation method.The active improved chemical type hydrocracking catalyst described in the present application, using special preparation process, make metal component selectively deposit on the binder between zeolite particles, catalyst activity has been improved.The catalyst includes the following components by weight fraction: a) at least one selected from mordenite, ZSM-5, beta zeolite;B) including group VIII metal element and group VIB metal oxide;C) alumina binder, wherein more than 65% of metal functional component selectively deposit on the binder.The catalyst can be used to convert catalytic diesel oil into light aromatic hydrocarbon and light hydrocarbon cracking material, etc.Aromatic hydrocarbon, olefin chemical raw material, compared with the catalyst with uniform distribution of metal component, the catalyst activity and aromatic product purity are higher.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of catalyst technology in petroleum refining, and particularly relates to a chemical hydrocracking catalyst with improved activity and a preparation method and application thereof. BACKGROUND

[0002] Hydrocracking refers to those hydrogenation processes in which more than 10% of molecules in raw oil are made smaller, and is one of the main processes for deep processing of heavy distillate oil. Hydrocracking technology is one of the important means for secondary processing of crude oil and lightening of heavy oil. Due to its strong adaptability to raw materials, flexible operation and product scheme, and good product quality, it has become an important way to produce high-quality light oil and solve the source of chemical raw materials. In the existing process, the light oil type hydrocracking process takes gasoline or naphtha as the target product, and the naphtha is produced into light aromatic hydrocarbons through catalytic reforming process, or olefin products through steam cracking process.

[0003] Catalytic diesel and ethylene tar are rich in heavy aromatic hydrocarbons, in which C 11 + Aromatic hydrocarbons are mainly naphthalene series, indene series, acenaphthene and other double-ring aromatic hydrocarbons, and anthracene, phenanthrene and other three-ring aromatic hydrocarbons. Although their boiling points are in the diesel fraction, due to the presence of a large amount of condensed ring aromatic hydrocarbons, it is not economical to process them into diesel, and some enterprises can only use them as fuel oil. On the basis of refining type hydrocracking catalyst and process technology, technologies have been developed to convert catalytic diesel into high-octane gasoline blending components, as seen in Chinese patents CN101724454A and CN102839018A. The obtained heavy naphtha fraction has an aromatic content of 50-65%, which can be used as a high-octane gasoline blending component. The catalyst used contains 20-75wt% Y-type molecular sieve. However, due to the wide pore of Y-type molecular sieve, its space index is close to 20 (see literature Catalytic hydrocracking—mechanisms and versatility of the process, ChemCatChem 2012, 4, 292–306), and it does not have shape-selective effect on cracking non-aromatic hydrocarbons. C8, C9 and C 10 The aromatic content of the fraction is low, and the non-aromatic content is high, which cannot meet the indicators of reformate, and there are obvious difficulties in entering the aromatic complex device as raw material for producing benzene and p-xylene. Chinese patent CN1955262A discloses a two-stage hydrocracking method, in which the hydrocracking catalyst contains Pt-Pd noble metal and non-noble metal, Y zeolite with high pore space index and alumina, and the raw material is catalytic diesel. The aromatic potential value of the naphtha product is only 76.8%, and the purity of aromatic hydrocarbons is not high, which also cannot meet the requirements of the aromatic complex device.

[0004] Therefore, it is urgent to develop a chemical type hydrocracking catalyst to maximize the conversion of these poor oil products into light aromatics meeting the quality indicators of the aromatics complex, and to produce high-quality light hydrocarbons as raw materials for olefin production, to provide raw materials for chemical plants such as aromatics and olefins, and to realize the utilization of poor heavy aromatic resources and cost reduction and efficiency increase of the aromatics industry through refining and chemical integration. In particular, if a highly active chemical type hydrocracking catalyst can be developed, the conversion of non-aromatics on it will be significantly enhanced, the catalyst activity will be higher, and the purity of light aromatic products will be improved, which is of great significance for realizing the chemical utilization of poor hydrocarbon resources. SUMMARY

[0005] The technical problem to be solved by the present application is the low activity of the chemical type hydrocracking catalyst and the low purity of the obtained light aromatics. The present application provides a chemical type hydrocracking catalyst with improved activity, which is used in the hydrocracking reaction of aromatic-rich raw oil and has the characteristics of high activity and high purity of light aromatics.

[0006] One of the objects of the present application is to provide a chemical type hydrocracking catalyst comprising a solid acid zeolite, a binder and a metal functional component; wherein in the metal functional component, more than 65wt% of the metal functional component is deposited on the binder, and the balance is deposited on the solid acid zeolite; preferably, in the metal functional component, more than 80wt% of the metal functional component is deposited on the binder, and the balance is deposited on the solid acid zeolite.

[0007] In the above-mentioned catalyst, the solid acid zeolite is selected from at least one of mordenite, ZSM-5 and beta zeolite;

[0008] The binder is alumina;

[0009] The metal functional component includes a group VIII metal element and a group VIB metal oxide, wherein the group VIII metal element is selected from at least one of platinum, palladium, cobalt and nickel; the group VIB metal oxide is selected from at least one of molybdenum and tungsten oxides; in terms of 100 parts by weight of the catalyst, the group VIII metal element in the metal functional component is 0.05-6 parts, preferably 0.1-5 parts; the group VIB metal oxide is 3-30 parts, preferably 4-28 parts;

[0010] In terms of 100 parts by weight of the catalyst, the solid acid zeolite in the catalyst is 20-85 parts, the metal functional component is 3-45 parts, and the binder is 10-80 parts; preferably, the solid acid zeolite is 20-80 parts, the metal functional component is 5-30 parts, and the binder is 15-70 parts.

[0011] The second object of the present application is to provide a preparation method of the above-mentioned catalyst, which comprises the following steps of: loading the metal functional component on the binder, then mixing the solid acid zeolite to form, calcining, and reducing to obtain the catalyst; and the solid acid zeolite is optionally loaded with the metal functional component.

[0012] Step 1) preparing a metal compound solution containing a metal functional component, impregnating the binder with more than 65 wt% of the total amount of the metal compound solution, and depositing the metal compound on the binder by heating to obtain a binder pre-deposited with the metal compound;

[0013] Step 2) impregnating the solid acid zeolite with the remaining amount of the above-mentioned metal compound solution, depositing the metal compound on the solid acid zeolite by heating, mixing the obtained solid acid zeolite and the binder pre-deposited with the metal compound obtained in step 1) to form, and calcining to obtain a catalyst precursor;

[0014] Step 3) reducing the catalyst precursor obtained in step 2) by hydrogen to obtain the chemical type hydrocracking catalyst.

[0015] Specifically,

[0016] The metal compound of step 1) is selected from at least one of the soluble metal salts of Group VIII metals and at least one of the soluble metal salts of Group VIB metals, preferably at least one of the soluble metal salts of platinum, palladium, cobalt, nickel and at least one of the soluble metal salts of molybdenum and tungsten;

[0017] The heating temperature in step 1) is 150-400℃, and the heating time is 1-10h;

[0018] More than 80 wt% of the total amount of the metal compound solution is impregnated in the binder in step 1);

[0019] The calcination temperature in step 2) is 500-600℃, and the calcination time is 1-6h;

[0020] The reduction temperature in step 3) is 300-500℃, and the reduction time is 0.5-24h.

[0021] The metal functional component in the catalyst provided by the present application comprises Group VIII metal elements and Group VIB metal oxides, and the combination of the two can better control the hydrogenation strength of the catalyst.

[0022] The Group VIII metal component can be pre-loaded on the binder by impregnation and then formed into the catalyst, preferably using a water-soluble compound of the Group VIII metal for impregnation. Typical platinum group compounds that can be used are chloroplatinic acid, ammonium chloroplatinate, bromoplatinic acid, platinum dichloride, platinum tetrachloride hydrate, tetraamine platinum chloride, tetraamine platinum nitrate, dichlorocarbonyl platinum dichloride, dinitrodiamino platinum, platinum chloride, platinum chloride dihydrate, platinum nitrate, preferably tetraamine platinum chloride as a source of the particularly preferred platinum component. Typical palladium group compounds that can be used are palladium chloride, palladium chloride dihydrate, palladium nitrate dihydrate, tetraamine palladium chloride, preferably tetraamine palladium chloride as a source of the particularly preferred palladium component. Typical cobalt group compounds that can be used are cobalt nitrate, cobalt chloride, cobalt oxalate, preferably cobalt nitrate as a source of the particularly preferred cobalt component. Typical nickel group compounds that can be used are nickel nitrate, nickel sulfate, nickel halide, nickel oxalate, nickel acetate, preferably nickel nitrate as a source of the particularly preferred nickel component.

[0023] The Group VIB metal oxide can be pre-loaded on the binder by impregnation and then formed into the catalyst, preferably using a water-soluble compound of the Group VIB metal for impregnation.

[0024] A third object of the present application is to provide the use of the chemical type hydrocracking catalyst or the chemical type hydrocracking catalyst prepared by the above preparation method in the conversion of poor heavy aromatics.

[0025] The use comprises the step of contacting the chemical type hydrocracking catalyst with a poor heavy aromatics feedstock under conversion conditions. The poor heavy aromatics feedstock is selected from at least one of catalytic diesel oil, ethylene tar, preferably at least one of catalytic diesel oil, ethylene tar after hydrofining; the poor heavy aromatics feedstock has a C 11 and the aromatics weight percentage is 60-100%; the conversion conditions include: temperature 300-460℃, hydrogen partial pressure 3-10.0 MPa, liquid phase space velocity 0.1-4.0 h -1 , hydrogen to hydrocarbon volume ratio 300-4000.

[0026] The reaction of the conversion of the above poor heavy aromatics refers to the selective saturation, ring opening and dealkylation of the C 11 + heavy aromatics in the presence of hydrogen to obtain light products. The light products refer to the aromatics with carbon number less than 11, including C6aromatics, such as benzene; C7aromatics, such as toluene; C8aromatics, such as ethylbenzene, xylene; C9aromatics, such as methyl ethyl benzene, propyl benzene, trimethyl benzene; C 10 aromatics, such as tetramethyl benzene, dimethyl ethyl benzene, diethyl benzene.

[0027] In the catalyst of the present application, since the active metal component is pre-loaded on the binder, no significant physical covering and chemical combination (such as the formation of nickel aluminate) with the acid centers of the zeolite occurs during the shaping and subsequent calcination process, so that the amount of strong B acid centers in the zeolite is higher than that of the catalyst in which the active metal component is mainly loaded on the zeolite, and the catalyst exhibits higher activity in the conversion of poor heavy aromatics, and the purity of the obtained aromatic product is higher. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 N2 adsorption comparison chart of the catalysts obtained by the pre-impregnation method of Example 1 and the direct kneading method of Comparative Example 1. In the chart, the vertical coordinate is the adsorption amount, unit m 2 / g; the horizontal coordinate is the relative pressure, unit P / P0. From the chart, it can be seen that the two catalysts have the same content of molecular sieve and alumina, and the catalyst obtained by the pre-impregnation method of Example 1 has a higher N2 adsorption amount, indicating that it has a larger specific surface area and better diffusion effect. Figure 1

[0029] Figure 2 TEM chart of the hydrogen cracking catalyst prepared by the pre-impregnation method in Example 1, indicating that the composite metal phase particles are mainly distributed on the alumina carrier. DETAILED DESCRIPTION

[0030] The present application will be further described and explained with specific embodiments. However, it should be pointed out that the protection scope of the present application is not limited by this, but is determined by the claims in the appendix. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, and these simple modifications all belong to the protection scope of the present application.

[0031] In addition, it should be pointed out that the various specific technical features described in the following specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present application will not further describe various possible combinations.

[0032] In addition, various different embodiments of the present application can also be combined in any manner, as long as it does not contradict the idea of the present application, and the technical solutions thus formed are part of the original disclosure of the present specification, and also fall within the protection scope of the present application, and should not be regarded as new content that has not been disclosed or anticipated in the present text, unless the person skilled in the art considers that the combination is obviously unreasonable.

[0033] In the context of the present specification, except for the explicitly described content, any matters or items that are not mentioned are directly applicable to those known in the art without any change.​

[0034] All publications, patent applications, patents, and other references mentioned in this specification are herein incorporated by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as is commonly understood by one of ordinary skill in the art. In case of conflict between the definitions in this specification and that of any incorporated reference, the definition in this specification prevails.

[0035] When the specification states a genus of elements with limitations of "comprising those known to those of ordinary skill in the art", "comprising those present in the art", those known to those of ordinary skill in the art", or the like, it is intended to cover a combination of elements from the group to provide any member of the genus.

[0036] All percentages, parts, ratios, etc. as used herein are by weight, unless otherwise specified; temperatures are in °C; pressure is at or near atmospheric; and air velocities are liquid hourly space velocities (LHSV).

[0037] The endpoints of the ranges and any values described herein are not limited to the precise values stated. The ranges and values should be construed to be roughly about the ranges or values. For ranges, the endpoints are included; for values, the value is included. The disclosure herein includes each and every value and range of values. It is also to be understood that the disclosure is not limited to the specific examples, methods, or examples thereof, but includes any alternatives and modifications thereto. The disclosure includes all available isotopic variations. The disclosure includes all possible combinations that can be made by combining the various technical solutions described herein.

[0038] Test methods and standards referred to in the detailed description of the application:

[0039] 1. In the present application, the composition of the catalysts was analyzed by ICP (inductively coupled plasma) and XRF (X-ray fluorescence) methods. The composition ratio of the VIB group metal oxides was determined by XPS (X-ray photoelectron spectroscopy) method. The ICP test conditions were: Varian 700-ES series XPS instrument. The XRF test conditions were: Rigaku ZSX 100e type XRF instrument. The XPS test conditions were: Perkin Elmer PHI 5000C ESCA type X-ray photoelectron spectrometer, using Mg K excitation light source, operating voltage l0kV, current 40mA, vacuum degree 4.0x10 -8 Pa.

[0040] 2. Low temperature N2 adsorption-desorption experiment utilizes the principle of physical adsorption and capillary condensation of nitrogen on the surface of solid under saturated temperature condition. The experiment is conducted by using Tristar 3000 adsorption instrument of Micromeritics Company of USA under liquid nitrogen saturated temperature (77K), and N2 isothermal adsorption-desorption curve is obtained by changing pressure.

[0041] 3. High resolution TEM characterization is conducted on Tecnai G220 transmission electron microscope.

[0042] 4. In the present application, light weight product composition is determined by gas chromatography. The chromatograph is Agilent 7890A, equipped with FID detector, FFAP capillary chromatographic column is used for separation, and the chromatographic column is subjected to programmed temperature, initial temperature is 90℃, maintained for 15 minutes, then heated to 220℃ at a rate of 15℃ / min, and maintained for 45 minutes.

[0043] 5. In the present application, all molecular sieve raw materials and alumina raw materials are taken from Sinopec Catalyst Branch.

[0044] The calculation basis of main result data involved in the embodiment part of the present application is as follows:

[0045] 1. C 11 + The conversion rate calculation formula of aromatic hydrocarbon is as follows:

[0046]

[0047] 2. The aromatic hydrocarbon content calculation formula in heavy naphtha is as follows:

[0048]

[0049] The raw materials involved in the embodiment part of the present application are as follows:

[0050] 1. The composition of raw oil is shown in Table 1, and the raw oil 1 is catalytic diesel oil after hydrofining.

[0051] 2. The raw materials involved in the embodiment and comparative examples of the present application include but are not limited to catalysts, which can be obtained by market.

[0052] Table 1. Composition and properties of raw oil 1

[0053] Feed oil 1 Density (4°C) 0.92 Sulfur (wt ppm) 75 Nitrogen (wt ppm) 34 Non-aromatic hydrocarbons (wt) 17.60 Monocyclic aromatic hydrocarbons (wt%) 70.27 Condensed ring aromatic hydrocarbons (wt%) 12.13 C 11 + A content (wt%) 82.24 Initial boiling point 155 5％ 178 10％ 186 30％ 220 50％ 239 70％ 261 90％ 283 Final boiling point 321

[0054]

Comparative Example 1

[0055] A catalyst carrier was prepared by mixing zeolite beta (SAR = 25) with pseudoboehmite (alumina content 70 wt%) in a ratio of 1:1, adding 1 wt% of sesbania powder and 2 wt% of nitric acid, kneading, extruding, drying at 120°C and calcining at 550°C for 4 hours in air. A bimetallic solution was prepared from cobalt nitrate and ammonium tungstate and impregnated into the catalyst carrier by the incipient wetness method. The impregnated catalyst carrier was dried at 120°C and calcined at 500°C for 2 hours in air. The catalyst precursor was reduced in hydrogen at 450°C for 4 hours to obtain catalyst C1. The composition of catalyst C1 is shown in Table 2 (in parts by weight): 5 parts Co - 2.3 parts WO2 - 2.9 parts WO3 / 52 parts zeolite beta - 37.8 parts Al2O3. The metal components were uniformly distributed on the catalyst. The specific surface area of the catalyst was 356 m 2 / g, Figure 1 The isothermal adsorption curve is shown in Figure 2.

[0056] The feedstock 1 was continuously injected into a fixed bed reactor. The reaction conditions were: temperature 390°C, pressure 5.0 MPa, LHSV 2.0 h -1 and hydrogen / hydrocarbon volume ratio 1000.

[0057] After 500 hours of stable operation, the sample was analyzed. The liquid product greater than 65°C (including heavy naphtha and unconverted C 11 + The composition is shown in Table 3 (in wt%). The C5 + The liquid (C5+ components) yield was 85.21 wt%. The non-aromatic components were 15.61 wt% of the liquid product greater than 65°C. The aromatic content of the heavy naphtha (65-210°C) was 68.61 wt%. The C 11 + A was 15.61 wt%. The C 11 + The conversion of C

[0058]

Comparative Example 2

[0059] A mixture of cobalt nitrate and ammonium tungstate was prepared as a bimetallic solution, which was divided into two parts in the ratio of 4:6. 52 parts of hydrogen form beta zeolite (SAR = 25) were mixed with 40% of the bimetallic solution and appropriate amount of water to form a suspension with a solid content of 25%, which was spray dried to obtain beta zeolite powder loaded with metal components. 54 parts of pseudo-boehmite (alumina dry basis content 70 wt%) were mixed with 60% of the bimetallic solution and appropriate amount of water to form a suspension with a solid content of 20%, which was spray dried to obtain alumina powder loaded with metal components. The beta zeolite powder and alumina powder loaded with metal components were mixed thoroughly, and then 1% of the total mass of sesbania powder and 2% of the total mass of nitric acid were added. After kneading, extruding and drying at 120°C, the catalyst precursor was obtained by calcining at 550°C in air for 4 hours. The catalyst precursor was reduced under hydrogen conditions to 450°C and maintained for 4 hours to obtain catalyst C2. The composition of catalyst C2 is shown in Table 2 (in parts by weight): 5 parts of Co-2.3 parts of WO2-2.9 parts of WO3 / 52 parts of beta zeolite-37.8 parts of Al2O3, 40% of the metal components being loaded on the beta zeolite and 60% of the metal components being loaded on the alumina.

[0060] The raw material 1 was continuously injected into a fixed bed reactor. The reaction conditions were: temperature 390°C, pressure 5.0 MPa, LHSV 2.0 h -1 , hydrogen / hydrocarbon volume ratio 1000.

[0061] After 500 hours of stable operation, the sample was analyzed. The liquid product greater than 65°C (including heavy naphtha and unconverted C 11 + The composition is shown in Table 3 (content of each component in wt%). C5 + The liquid (C5 and above) liquid yield was 81.87 wt%. Among them, NA refers to non-aromatic components. The aromatic content in the heavy naphtha of 65-210°C was 71.89 wt%. The C 11 + A accounted for 13.65 wt%, and the calculated C 11 + The conversion of C

[0062]

Example 1

[0063] A solution of bimetallic was prepared from cobalt nitrate and ammonium tungstate. 54 parts of pseudo-boehmite (alumina dry basis content 70 wt%) was added to the bimetallic solution and an appropriate amount of water to form a suspension with a solid content of 20%, which was spray dried to obtain alumina powder loaded with metal components. 52 parts of β-zeolite (SAR = 25) powder and the above alumina powder loaded with metal components were mixed thoroughly, then 1% of the total mass of sesbania powder and 2% of the total mass of nitric acid were added, and after kneading, extrusion and drying at 120°C, the catalyst precursor was obtained by calcination in air at 550°C for 4 hours. The catalyst precursor was reduced under hydrogen conditions to 450°C and maintained for 4 hours to obtain catalyst C3. The composition in parts by weight is (see Table 2): 5 parts of Co - 2.3 parts of WO2 - 2.9 parts of WO3 / 52 parts of β-zeolite - 37.8 parts of Al2O3, 100% of the metal components being loaded on alumina.

[0064] The specific surface area of the catalyst was characterized by low temperature N2 adsorption as 356 m 2 / g, Figure 1 The isothermal adsorption loop is shown in the figure above. Figure 2 The high-resolution TEM image of the C3 catalyst is shown above. The β-zeolite has a clear interface, and the amorphous alumina carrier is wrapped outside the crystal. The light-colored bright spots are uniformly distributed metal particles. It can be seen that the metal particles are densely distributed on the alumina, and the amount of metal particles on the β-zeolite with obvious crystal characteristics is very low.

[0065] The raw material 1 was continuously injected into a fixed bed reactor. The reaction conditions were: temperature 390°C, pressure 5.0 MPa, LHSV space velocity 2.0 hours -1 , hydrogen / hydrocarbon volume ratio 1000.

[0066] After 500 hours of stable operation, the sample was analyzed. The liquid product greater than 65°C (including heavy naphtha and unconverted C 11 + The composition is shown in Table 3 (the content of each component is in wt%). C5 + The liquid (C5 and above components) liquid yield was 76.59 wt%. Among them, NA refers to non-aromatic components. The aromatic content in the heavy naphtha of 65-210°C was 80.01 wt%. The C 11 + A accounted for 9.71 wt%, and the calculated C 11 + The conversion of A was 92.56 wt%.

[0067]

Example 2

[0068] A solution of the bimetallic was prepared from nickel nitrate and ammonium molybdate. 40 parts of pseudoboehmite (alumina dry basis content 70 wt%) were added to the bimetallic solution and an appropriate amount of water to form a suspension with a solid content of 20%, which was spray dried to obtain alumina powder loaded with the metal components. 32 parts of beta zeolite (SAR = 75) powder, 10 parts of ZSM-5 powder (SAR = 38) and the alumina powder loaded with the metal components were thoroughly mixed, 3% of the total mass of sesbania powder and 2.4% of the total mass of nitric acid were added, and the mixture was kneaded, extruded, dried at 110°C and calcined in air at 550°C for 4 hours to obtain the desired catalyst precursor. The catalyst precursor was reduced under hydrogen conditions up to 450°C and maintained for 4 hours to obtain catalyst C4. The composition in parts by weight is (see Table 2): 4.5 parts of Ni - 18.7 parts of MoO2- 6.8 parts of MoO3 / 32 parts of beta zeolite - 10 parts of ZSM-5 - 28 parts of Al2O3, with 100% of the metal components loaded on the alumina.

[0069] The feedstock 1 was continuously injected into a fixed bed reactor. The reaction conditions were: temperature 360°C, pressure 6.5 MPa, LHSV 2.0 h"1, hydrogen / hydrocarbon volume ratio 1000. -1

[0070] After 500 hours of stable operation, the sample was analyzed. The liquid product greater than 65°C (including heavy naphtha and unconverted C 11 + The composition is shown in Table 3 (content of each component in wt%). C5 + The liquid (C5 and above) yield was 69.54 wt%. Among them, NA refers to non-aromatic components. The aromatic content in the heavy naphtha of 65-210°C was 84.89 wt%. The C 11 + A accounted for 20.05 wt%, and the calculated C 11 + The conversion of A was 86.06 wt%.

[0071]

Example 3

[0072] ​A bimetallic solution was prepared from nickel nitrate and ammonium molybdate, and was divided into two parts in the ratio of 15:85. 32 parts of β-zeolite (SAR = 75) powder, 10 parts of ZSM-5 powder (SAR = 38) powder, 15% of the bimetallic solution and an appropriate amount of water were added to form a suspension with a solid content of 25%, and spray drying was performed to obtain a composite zeolite powder loaded with metal components. 40 parts of pseudo-boehmite (alumina dry basis content 70 wt%) were added to 85% of the bimetallic solution and an appropriate amount of water to form a suspension with a solid content of 20%, and spray drying was performed to obtain an alumina powder loaded with metal components. After the composite zeolite powder loaded with metal components and the alumina powder loaded with metal components were thoroughly mixed, 3% of the total mass of sesbania powder and 2.4% of the total mass of nitric acid were added, and kneading, extrusion, drying at 110°C and calcination at 550°C in air for 4 hours were performed to obtain the desired catalyst precursor. The catalyst precursor was reduced under hydrogen conditions to 450°C and maintained for 4 hours to obtain catalyst C5. The composition (see Table 2) was 4.5 parts of Ni-18.7 parts of MoO2-6.8 parts of MoO3 / 32 parts of β-zeolite-10 parts of ZSM-5-28 parts of Al2O3, 85% of the metal components were loaded on alumina, and 15% of the metal components were loaded on zeolite.

[0073] The raw material 1 was continuously injected into a fixed bed reactor. The reaction conditions were: temperature 360°C, pressure 6.5 MPa, LHSV 2.0 h-1, and hydrogen / hydrocarbon volume ratio 1000. -1

[0074] After 500 hours of stable operation, the sample was analyzed. The liquid product greater than 65°C (including heavy naphtha and unconverted C 11 + The composition is shown in Table 3 (each component content is in wt%). The C5 + The liquid (C5 and above components) liquid yield was 71.07 wt%. Among them, NA refers to non-aromatic components. The aromatic content in the heavy naphtha of 65-210°C was 81.27 wt%. The C 11 + A accounted for 21.19 wt%, and the calculated C 11 + The conversion of A was 84.94 wt%.

[0075]

Example 4

[0076] ​A three-metal solution was prepared from chloroplatinic acid, palladium chloride and ammonium molybdate. 60 parts of pseudo-boehmite (alumina dry basis content 70 wt%) were added to the three-metal solution and an appropriate amount of water to form a suspension with a solid content of 20%, which was spray dried to obtain alumina powder loaded with metal components. The alumina powder loaded with metal components was mixed with 50 parts of mordenite (SAR = 18), 2% of the total mass of Euphorbia and 2.8% of the total mass of nitric acid was added, kneaded, extruded, dried at 110°C and then calcined in air at 550°C for 4 hours to obtain the desired catalyst precursor. The catalyst precursor was reduced under hydrogen conditions to 450°C and maintained for 4 hours to obtain catalyst C6. The composition in parts by weight is (see Table 2): 0.05 parts of Pt - 0.05 parts of Pd - 5.3 parts of MoO2 - 2.6 parts of MoO3 / 50 parts of mordenite - 42 parts of Al2O3, 100% of the metal components being loaded on the alumina.

[0077] The raw material 1 was continuously injected into a fixed bed reactor. The reaction conditions were: temperature 370°C, pressure 6.5 MPa, LHSV 2.0 h-1, hydrogen / hydrocarbon volume ratio 1000. -1

[0078] After 500 hours of stable operation, the sample was analyzed. The liquid product greater than 65°C (including heavy naphtha and unconverted C 11 + The composition is shown in Table 3 (content of each component in wt%). C5 + The liquid (C5 and above components) yield was 83.82 wt%. Among them, NA refers to non-aromatic components. The aromatic content in the heavy naphtha of 65-210°C was 76.55 wt%. The C 11 + A accounted for 30.61 wt%, and the calculated C 11 + The conversion of A was 74.34 wt%.

[0079] Table 2. Catalyst composition in the comparative examples and examples

[0080]

[0081] Table 3. Reaction product data of the catalysts in the comparative examples and examples

[0082]

[0083] In the process of lightening the raw material, light C3 and C4 hydrocarbons are produced as gas phase products. As can be seen from the data in Table 3, the liquid yield in the examples of the present application is lower, indicating that the catalyst provided by the present application has higher activity and higher conversion rate of the raw material.​

Claims

1. A hydrocracking catalyst of the chemical type comprising a solid acid zeolite, a binder and a metal functional component; wherein, The metal functional component is deposited on the binder in an amount of 65wt% or more, and the rest is deposited on the solid acid zeolite; the solid acid zeolite is selected from at least one of mordenite, ZSM-5, and beta zeolite, and the binder is alumina; The metal functional component is loaded on the binder, and then mixed with the solid acid zeolite to form, calcined, and reduced to obtain the catalyst; the metal functional component includes a group VIII metal element and a group VIB metal oxide, the group VIII metal element is selected from at least one of platinum, palladium, cobalt, and nickel, and the group VIB metal oxide is selected from at least one of molybdenum and tungsten oxides; the solid acid zeolite is 20-85 parts, the metal functional component is 3-45 parts, the binder is 10-80 parts, the group VIII metal element is 0.05-6 parts, and the group VIB metal oxide is 3-30 parts, all based on 100 parts by weight of the catalyst.

2. The catalyst according to claim 1, characterized in that, The metal functional component is deposited on the binder in an amount of 65wt% or more, and the rest is deposited on the solid acid zeolite; the solid acid zeolite is selected from at least one of mordenite, ZSM-5, and beta zeolite, and the binder is alumina; 3. The catalyst according to claim 1, characterized in that, The group VIII metal element is 0.1-5 parts, and the group VIB metal oxide is 4-28 parts, all based on 100 parts by weight of the catalyst.

4. The catalyst according to claim 1, characterized in that, The solid acid zeolite is 20-80 parts, the metal functional component is 5-30 parts, and the binder is 15-70 parts, all based on 100 parts by weight of the catalyst.

5. A preparation method of the catalyst according to any one of claims 1-4, comprising loading the metal functional component on the binder, and then mixing the solid acid zeolite to form, calcining, and reducing to obtain the catalyst; the solid acid zeolite is optionally loaded with the metal functional component.

6. The preparation method according to claim 5, characterized in that, The preparation method specifically comprises the following steps: Step 1) preparing a metal compound solution containing the metal functional component, immersing the binder in the metal compound solution in an amount of 65wt% or more, heating to deposit the metal compound on the binder, and obtaining the binder pre-deposited with the metal compound; Step 2) immersing the solid acid zeolite in the rest of the metal compound solution, heating to deposit the metal compound on the solid acid zeolite, mixing the obtained solid acid zeolite and the binder pre-deposited with the metal compound obtained in step 1) to form, and calcining to obtain a catalyst precursor; Step 3) reducing the catalyst precursor obtained in step 2) by hydrogen to obtain the chemical type hydrocracking catalyst.

7. The preparation method according to claim 6, characterized in that, The metal compound in step 1) is selected from at least one of a group VIII metal soluble metal salt and at least one of a group VIB metal soluble metal salt.

8. The preparation method according to claim 7, characterized in that, The metal compound of step 1) is selected from at least one of soluble metal salts of platinum, palladium, cobalt, nickel and at least one of soluble metal salts of molybdenum, tungsten.

9. The preparation method of claim 6, wherein, the heating temperature in step 1) is 150-400℃, and the heating time is 1-10h; and / or, in step 1), the metal compound solution accounts for more than 80wt% of the total amount; and / or, the calcination temperature in step 2) is 500-600℃, and the calcination time is 1-6h; and / or, the reduction temperature in step 3) is 300-500℃, and the reduction time is 0.5-24h.

10. Use of a chemical hydrocracking catalyst according to any one of claims 1-4, or a chemical hydrocracking catalyst prepared by the preparation method according to any one of claims 5-9, in the conversion of poor heavy aromatic hydrocarbons.

11. Use according to claim 10, characterized in that, The use comprises the step of contacting the chemical hydrocracking catalyst with a poor heavy aromatic hydrocarbon feedstock under conversion conditions.

12. The use of claim 10 or 11, wherein, the poor heavy aromatic hydrocarbon feedstock is selected from at least one of catalytic diesel oil, ethylene tar; and / or, The inferior heavy aromatic hydrocarbon raw material has a C 11 and the above aromatic hydrocarbon weight percentage is 60-100%.

13. The use according to claim 11, characterized in that, The conversion conditions include: temperature 300-460℃, hydrogen partial pressure 3-10.0MPa, liquid phase space velocity 0.1-4.0h-1, and hydrogen / hydrocarbon volume ratio 300-4000. -1 , hydrogen partial pressure 3-10.0MPa, liquid phase space velocity 0.1-4.0h-1, and hydrogen / hydrocarbon volume ratio 300-4000.

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