Catalytic compositions for increasing propylene concentration at high light liquid yield, methods of making, catalysts, and methods of catalytic conversion of hydrocarbon oils

Abstract

The present disclosure relates to a catalytic composition for increasing propylene concentration at high light liquid yield, and a preparation method, catalyst and application thereof, which is composed of rare earth modified MFI molecular sieve, phosphoric aluminum colloid, other inorganic binder and clay; the content of the rare earth modified MFI molecular sieve is 10-65 wt%, the content of rare earth calculated as rare earth oxide is 0.5-8 wt%, the content of other inorganic binder calculated as oxide is 1-25 wt%, the content of clay is 0-30 wt%, and the content of phosphoric aluminum colloid is 3-40 wt%, all based on the dry weight of the catalytic composition; the rare earth modified MFI molecular sieve contains a first phosphorus component, and the phosphoric aluminum colloid contains a second phosphorus component; the total content of the first and second phosphorus components calculated as P2O5 is 10-35 wt%, and the second phosphorus component accounts for 50-95 wt% of the total phosphorus content, all based on the dry weight of the catalytic composition. The catalytic composition of the present disclosure can increase the content of propylene in catalytic cracking liquefied petroleum gas, and the total yield of gasoline and LPG is high.

Description

Technical Field

[0001] This application relates to a catalytic composition for increasing propylene concentration at high light liquid yields, a method for preparing the same, a catalyst, and a method for catalytic conversion of hydrocarbon oils. Background Technology

[0002] For most catalytic cracking units, adding catalysts is an effective technique for increasing the production of low-carbon olefins, and the acidity of the catalyst and the shape-selective effect of its pores determine the yield of low-carbon olefins in the product. Zeolites with five-membered ring structures possess unique pore structures and acidity, giving them excellent catalytic performance in the deep processing of low-carbon olefins. To increase the production of light olefins and propylene, using catalysts or additives containing ZSM-5 molecular sieves is an effective technique.

[0003] Prior art discloses a five-membered ring high-silica zeolite catalyst for light olefins in a fluidized bed catalytic cracking unit. The catalyst comprises (a) a five-membered ring high-silica zeolite, (b) 8-24 wt% phosphorus, calculated as P2O5 based on the five-membered ring high-silica zeolite particles, and 1-10 wt% iron oxide, calculated as Fe2O3, located outside the five-membered ring high-silica zeolite framework. The catalyst is fluidizable and has an average particle size of about 20-200 micrometers. This catalyst composition can increase the yield of light olefins, such as propylene, in fluidized bed catalytic cracking (FCC), but the increase in propylene results in a significant loss of gasoline yield. A cracking catalyst for increasing propylene concentration is disclosed in the prior art. This catalyst, on a dry basis, consists of 10-65 wt% modified ZSM-5 molecular sieve, 0-60 wt% clay, 15-60 wt% inorganic oxide binder, 0.5-15 wt% metal additives selected from one or more Group VIIIB metals, and 2-25 wt% phosphorus additives. The modified ZSM-5 molecular sieve is modified with phosphorus and a metal selected from Fe, Co, or Ni. Its anhydrous chemical expression, on an oxide basis, is (0-0.3)Na₂O·(0.5-5)Al₂O₃·(1.3-10)P₂O₅·(0.7-15)M x O y (70-97)SiO2, where x represents the number of atoms of M, and y represents a number required to satisfy the oxidation state of M. The metal and phosphorus additives mentioned are both based on oxides. This cracking catalyst, when applied to the catalytic cracking process of petroleum hydrocarbons, significantly increases the propylene concentration in liquefied petroleum gas (LPG) while increasing the yield and octane number of gasoline. However, gasoline yield decreases significantly, while diesel and slurry yields do not decrease.

[0004] Currently, existing catalytic additives used in catalytic cracking processes increase the amount of low-carbon olefins in liquefied petroleum gas (LPG) while resulting in significant gasoline losses and no increase in light liquid recovery. When a large amount of additive is added, it weakens the conversion capacity of heavy oil, and the light liquid recovery may actually decrease. Summary of the Invention

[0005] The purpose of this disclosure is to provide a catalytic composition for increasing propylene concentration at high light liquid yields, a method for preparing the same, a catalyst, and a method for catalytic conversion of hydrocarbon oils. The catalytic composition of this disclosure can increase the propylene content in catalytic cracking liquefied petroleum gas while improving the overall yield of gasoline and LPG.

[0006] To achieve the above objectives, the first aspect of this disclosure provides a catalytic composition for increasing propylene concentration at high light liquid yields, the catalytic composition comprising rare earth-modified MFI molecular sieves, aluminum phosphate gel, other inorganic binders, and clay;

[0007] Based on the dry weight of the catalytic composition, the content of the rare earth modified MFI molecular sieve is 10-65% by weight, the content of the other inorganic binders (calculated as oxides) is 1-25% by weight, the content of the clay is 0-30% by weight, and the content of the phosphate aluminum colloid (calculated as P2O5 and Al2O3) is 3-40% by weight.

[0008] The rare earth content in the rare earth modified MFI molecular sieve is 0.5-8% by weight, and the rare earth is calculated as rare earth oxides; the rare earth modified MFI molecular sieve contains a first phosphorus component, and the phosphorus aluminum colloid contains a second phosphorus component. Based on the dry weight of the catalytic composition, the total content of the first phosphorus component and the second phosphorus component, calculated as P2O5, is 10-35% by weight, and the second phosphorus component accounts for 50-95% of the total phosphorus content.

[0009] Optionally, the wear index of the catalytic composition is 0-2.5% / h.

[0010] Optionally, based on the dry weight of the aluminum phosphate gel, the aluminum phosphate gel contains 10-40% by weight of Al2O3 and 60-90% by weight of P2O5.

[0011] Optionally, based on the dry weight of the catalytic composition, the content of the rare earth-modified MFI molecular sieve is 15-63% by weight, the content of rare earth as rare earth oxides is 1-6% by weight, the content of the other inorganic binders as oxides is 2-20% by weight, the content of clay is 1-15% by weight, and the content of phosphate aluminum colloid is 8-35% by weight; the rare earth content in the rare earth-modified MFI molecular sieve is 1-6% by weight.

[0012] Optionally, based on the dry weight of the catalytic composition, the total content of the first phosphorus component and the second phosphorus component, calculated as P2O5, is 15-32% by weight, and the second phosphorus component accounts for 60-90% of the total phosphorus content.

[0013] Optionally, the other inorganic binder is one or more selected from boehmite, alumina, aluminum sol, silica-alumina sol, and silica sol;

[0014] The clay is selected from one or more of kaolin, sepiolite, attapulgite, rettoite, montmorillonite, and diatomite.

[0015] The rare earth modified MFI molecular sieve is selected from phosphorus and rare earth-containing MFI molecular sieves, and / or phosphorus, rare earth and transition metal-containing MFI molecular sieves, wherein the transition metal is a transition metal other than rare earth, preferably one or more of Fe, Co or Ni.

[0016] Preferably, in the phosphorus- and rare earth-containing MFI molecular sieve, the content of the first phosphorus component, calculated as P2O5, is 0.5-10% by weight, and the rare earth content, calculated as RE2O3, is 0.5-8% by weight.

[0017] Preferably, in the MFI molecular sieve containing phosphorus, rare earth and transition metals, the content of transition metal elements (calculated as oxides) is 0.5-10% by weight, the content of the first phosphorus component (calculated as P2O5) is 0.5-10% by weight, and the content of rare earth elements (calculated as RE2O3) is 0.5-8% by weight.

[0018] A second aspect of this disclosure provides a method for preparing the catalytic composition provided in the first aspect of this disclosure, the method comprising:

[0019] S1. Mix the MFI molecular sieve, the other inorganic binder, the clay and water to form a slurry, and adjust the pH value of the slurry to be greater than 2.5 to obtain the first slurry.

[0020] S2. The rare earth modified first slurry is mixed with the highly active phosphorus aluminum colloid and then spray-dried and calcined to obtain the catalytic composition.

[0021] Optionally, the aluminum phosphate gel is prepared by a method comprising the following steps:

[0022] (1) At 25-90℃, the first aluminum source and water are mixed and pulped, and the resulting slurry is mixed and stirred with concentrated phosphoric acid to obtain a transparent colloid;

[0023] (2) At 25-50℃, the second aluminum source is mixed and reacted with the transparent colloid to obtain the phosphorus aluminum glue.

[0024] Optionally, in step (1), the weight ratio of the first aluminum source to the concentrated phosphoric acid is 100:(200-700), where the aluminum source is calculated as alumina and the phosphoric acid is calculated as phosphorus oxide;

[0025] In step (2), the dry weight ratio of the second aluminum source to the amount of the transparent colloid is 100:(500-2000), and the second aluminum source is calculated as alumina.

[0026] Optionally, the first aluminum source is selected from one or more of gibbsite, boehmite, boehmite, pseudoboehmite, and aluminosilicate;

[0027] The second aluminum source is one or more of aluminum oxide gel, aluminum oxide sol, and aluminum sol.

[0028] A third aspect of this disclosure provides a method for the catalytic conversion of hydrocarbon oil, the method comprising: reacting hydrocarbon oil with a catalyst, said catalyst containing the catalytic composition provided in the first aspect of this disclosure.

[0029] Optionally, the conditions for the catalytic cracking reaction of the heavy feedstock oil include: a temperature of 400-700℃ and a heavy hourly space velocity of 8-120 h⁻¹. -1 The weight ratio of the agent to oil is 1-20.

[0030] Through the above technical solution, the catalytic composition disclosed herein has high strength. It can be used as a main agent in catalytic cracking reactions, or as an auxiliary agent in catalytic cracking and catalytic pyrolysis reactions. When used in the catalytic cracking or catalytic pyrolysis reaction of heavy oil, especially heavy oil containing more saturated hydrocarbons, it can effectively increase the total yield of gasoline and LPG in the reaction products, while increasing the propylene content in liquefied petroleum gas.

[0031] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Detailed Implementation

[0032] The following provides a detailed description of specific embodiments of this disclosure. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit this disclosure.

[0033] The first aspect of this disclosure provides a catalytic composition for increasing propylene concentration at high light liquid yields, the catalytic composition comprising rare earth-modified MFI molecular sieves, aluminum phosphate gel, other inorganic binders, and clay;

[0034] Based on the dry weight of the catalytic composition, the content of the rare earth modified MFI molecular sieve is 10-65% by weight, the content of the other inorganic binders (calculated as oxides) is 1-25% by weight, the content of the clay is 0-30% by weight, and the content of the phosphate aluminum colloid (calculated as P2O5 and Al2O3) is 3-40% by weight.

[0035] The rare earth content in the rare earth-modified MFI molecular sieve is 0.5-8% by weight, and the rare earth is calculated as rare earth oxides; the rare earth-modified MFI molecular sieve contains a first phosphorus component, and the phosphorus aluminum colloid contains a second phosphorus component. Based on the dry weight of the catalytic composition, the total content of the first phosphorus component and the second phosphorus component, calculated as P2O5, is 10-35% by weight, and the second phosphorus component accounts for 50-95% of the total phosphorus content.

[0036] The catalytic composition disclosed herein contains rare-earth modified MFI molecular sieves, which can improve the hydrogen transfer index of the catalyst while reducing gasoline loss, thereby increasing the yield of low-carbon olefins. The contained phosphoaluminum colloid has high acid density and activity, exhibiting superior cracking capability and a longer service life. The synergistic effect of the phosphoaluminum colloid and the rare-earth modified MFI molecular sieves results in a high-strength catalytic cracking catalyst. When used in catalytic cracking and catalytic pyrolysis reactions, it can effectively increase the propylene content in catalytic cracked liquefied petroleum gas (LPG) while improving the overall yield of gasoline and LPG (i.e., light liquid yield).

[0037] In one specific embodiment of this disclosure, the aluminum phosphate gel contains 10-40% by weight of Al2O3 and 60-90% by weight of P2O5, based on the dry weight of the aluminum phosphate gel.

[0038] In one specific embodiment of this disclosure, the wear index of the catalytic cracking catalyst is 0-2.5% / h, preferably 1-2.2% / h. The wear index is determined using the straight tube method. The main method involves placing a certain amount of sample into a wear index measuring device and purging it at a constant gas velocity for five hours. The sample blown out in the first hour is discarded, and the sample blown out in the following four hours is collected. The average wear percentage per hour (the percentage of the weight of the sample smaller than 15 micrometers blown out per hour relative to the weight of the catalyst larger than 15 micrometers) is calculated, and this is called catalyst wear. The smaller the wear index, the better the anti-wear performance of the catalyst.

[0039] In one specific embodiment of this disclosure, based on the dry weight of the catalytic composition, the content of the rare earth-modified MFI molecular sieve is 15-63% by weight, the content of the other inorganic binders (calculated as oxides) is 2-20% by weight, the content of the clay is 1-15% by weight, and the content of the aluminum phosphate gel is 5-35% by weight. Preferably, based on the dry weight of the catalytic composition, the content of the rare earth-modified MFI molecular sieve is 10-65% by weight, the content of the other inorganic binders (calculated as oxides) is 1-25% by weight, the content of the clay is 0-30% by weight, and the content of the aluminum phosphate gel is 8-35% by weight.

[0040] In one specific embodiment of this disclosure, based on the dry weight of the catalytic composition, the total content of the first phosphorus component and the second phosphorus component, calculated as P2O5, is 15-32% by weight, and the second phosphorus component accounts for 60-90% of the total phosphorus content.

[0041] According to this disclosure, other inorganic binders can be those conventionally used by those skilled in the art in the preparation of catalysts. In one specific embodiment of this disclosure, the other inorganic binder is one or more selected from boehmite, alumina, aluminum sol, silica-alumina sol, and silica sol.

[0042] According to this disclosure, the clay can be any material conventionally used by those skilled in the art in the preparation of catalysts. In one specific embodiment of this disclosure, the clay is selected from one or more of kaolin, sepiolite, attapulgite, rettoiter, montmorillonite, and diatomaceous earth.

[0043] In one specific embodiment of this disclosure, the rare earth-modified MFI molecular sieve is selected from phosphorus- and rare earth-containing MFI molecular sieves, and / or phosphorus-, rare earth-, and transition metal-containing MFI molecular sieves, wherein the transition metal is a transition metal other than rare earth, preferably one or more of Fe, Co, or Ni. In this embodiment, the phosphorus- and rare earth-containing MFI molecular sieve uses phosphorus and rare earth as modifying components and does not contain other modifying components; the phosphorus-, rare earth-, and transition metal-containing MFI molecular sieve uses phosphorus, rare earth, and transition metal as modifying components and does not contain other modifying components. In a preferred embodiment, the phosphorus- and rare earth-containing MFI molecular sieve contains 0.5-10% by weight of the first phosphorus component (calculated as P2O5) and 0.5-8% by weight of the rare earth component (calculated as RE2O3). Preferably, the phosphorus-, rare earth-, and transition metal-containing MFI molecular sieve contains 0.5-10% by weight of the transition metal element (calculated as oxide), 0.5-10% by weight of the first phosphorus component (calculated as P2O5), and 0.5-8% by weight of the rare earth component (calculated as RE2O3).

[0044] In one specific embodiment of this disclosure, the rare earth modified MFI molecular sieve is selected from one or more of hydrogen-type MFI molecular sieves, phosphorus-containing MFI molecular sieves, and transition metal-containing MFI molecular sieves.

[0045] The second aspect of this disclosure provides a method for preparing the catalytic composition provided in the first aspect of this disclosure, the method comprising: S1, mixing the rare earth modified MFI molecular sieve, the other inorganic binder, the clay and water to form a slurry, adjusting the pH of the slurry to be greater than 2.5, to obtain a first slurry;

[0046] S2. The first slurry is mixed with the aluminum phosphate gel and then spray-dried and calcined to obtain the catalytic composition.

[0047] The method disclosed herein can prepare a catalytic composition with high strength. When used in the catalytic cracking reaction of feedstock oil, this catalytic composition can significantly increase the propylene content in catalytic cracked liquefied petroleum gas (LPG) while reducing the diesel and slurry content, thereby improving the overall yield of gasoline and LPG.

[0048] According to this disclosure, in step (1), an acid solution can be used to adjust the pH value of the slurry to 2.5. The acid in the acid solution can be any acid known to those skilled in the art, such as hydrochloric acid, sulfuric acid, and nitric acid. This disclosure does not impose specific restrictions on the concentration of the acid solution, and it can be selected according to actual needs, such as 0.01-10 mol / L.

[0049] In one specific embodiment of this disclosure, in step S1, the rare earth modified MFI molecular sieve, the clay and water are first mixed and pulped, and then the other inorganic binder is added to the resulting mixture for further mixing and pulping to obtain the first slurry, which is beneficial to further improve the activity and strength of the catalytic cracking catalyst.

[0050] According to this disclosure, spray drying is a technique well known to those skilled in the art, and specific methods will not be described in detail here. In one specific embodiment, the inlet temperature of the spray dryer can be 200-700°C, and the outlet temperature can be 80-200°C.

[0051] In one specific embodiment of this disclosure, the calcination temperature is 400-700℃, preferably 450-600℃, and the calcination time is 0.5-100 hours, preferably 0.5-10 hours.

[0052] In one specific embodiment of this disclosure, the highly active aluminum phosphate gel is prepared by a method comprising the following steps: (1) mixing and slurrying a first aluminum source and water at 25-90°C, then mixing and stirring the resulting slurry with concentrated phosphoric acid to obtain a transparent colloid; (2) reacting a second aluminum source with the transparent colloid at 25-50°C to obtain the aluminum phosphate gel. The method of this disclosure employs a two-step process to add an aluminum source to prepare the aluminum phosphate gel, promoting the full reaction of P and Al and improving matrix activity; simultaneously, it reduces the impact on the pore size of the molecular sieve by increasing the particle size. When used to prepare catalyst compositions, it can improve the activity and strength of the catalyst composition.

[0053] In one specific embodiment of this disclosure, in step (1), the weight ratio of the first aluminum source to the concentrated phosphoric acid is 100:(200-700), preferably 100:(300-680), where the aluminum source is calculated as alumina and the phosphoric acid as phosphorus oxide; in step (2), the dry weight ratio of the second aluminum source to the transparent colloid is 100:(500-2000). Within the above range, the appropriate ratio of each material allows for the preparation of a phosphorus-aluminum adhesive with superior bonding properties.

[0054] In one specific embodiment of this disclosure, in step (2), the mixing reaction time is 10-90 min.

[0055] According to this disclosure, the aluminum source can be known to those skilled in the art. In one specific embodiment of this disclosure, the first aluminum source is selected from one or more of gibbsite, boehmite, podophyllum, pseudoboehmite, and aluminum sol. According to this disclosure, the first aluminum source is one or more of aluminum oxide gel, aluminum oxide sol, and aluminum sol. In one specific embodiment of this disclosure, aluminum oxide gel is prepared by slurrying and acidifying aluminum oxide with an acid solution, wherein the acid in the acid solution can be, but is not limited to, one or more of hydrochloric acid, sulfuric acid, and nitric acid. In this disclosure, based on the total weight of the aluminum oxide gel, the aluminum oxide content in the aluminum oxide gel is 5-30 g by weight, and the pH value of the aluminum oxide gel is 0.5-4. In this disclosure, based on the total weight of the aluminum oxide sol, the aluminum oxide content in the aluminum oxide sol is 5-20 g by weight, and the pH value of the aluminum oxide sol is 1-5.

[0056] A third aspect of this disclosure provides a method for the catalytic conversion of hydrocarbon oil, the method comprising: reacting hydrocarbon oil with a catalyst, said catalyst containing the catalytic composition provided in the first aspect of this disclosure.

[0057] In one specific embodiment, the hydrocarbon oil is a heavy oil containing saturated hydrocarbons. The catalyst composition disclosed herein is particularly suitable for the catalytic conversion of heavy oil containing saturated hydrocarbons, and can increase the propylene content in catalytic cracking liquefied petroleum gas (LPG) while achieving high overall yields of gasoline and LPG.

[0058] In one specific embodiment of this disclosure, the catalyst is a catalyst composition provided in the first aspect of this disclosure, and the reaction is a catalytic cracking reaction of hydrocarbon oil.

[0059] In another specific embodiment of this disclosure, the catalyst is a mixture of the catalyst composition provided in the first aspect of this disclosure and an optional main catalyst, and the reaction is a catalytic cracking reaction of hydrocarbon oil. According to this disclosure, the main catalyst can be selected according to actual needs. In one specific embodiment of this disclosure, the main catalyst can be selected from catalytic cracking catalysts and / or catalytic pyrolysis catalysts, for example, including but not limited to one or more of RFCC catalysts, CGP catalysts, GOR olefin-reducing catalysts, and DCC catalysts.

[0060] In one specific embodiment of this disclosure, the reaction conditions include: a temperature of 400-700°C, preferably 450-550°C, and a weight hourly space velocity of 8-120 h⁻¹. -1 Preferably 8-80 hours -1 The catalyst-to-oil weight ratio is 1-20, preferably 3-15. The catalytic composition provided in this disclosure can be used in various existing catalytic cracking reactors, such as fixed-bed reactors, fluidized-bed reactors, riser reactors, and multi-reaction-zone reactors.

[0061] The present disclosure will be further illustrated by the following examples, but the present disclosure is not limited thereto.

[0062] The catalytic composition disclosed herein is evaluated using an ACE apparatus when used for performance evaluation in catalytic cracking reactions.

[0063] For details of the RIPP standard method described in this disclosure, please refer to "Analytical Methods in Petrochemical Industry", edited by Yang Cuiding et al., 1990 edition.

[0064] This disclosure uses the straight tube method to determine the wear index.

[0065] MPZ molecular sieve: an industrial product produced by Sinopec Catalysts Qilu Branch, with a P2O5 content of 7.25% by weight, a Fe2O3 content of 1.95% by weight, and a crystallinity of 72%.

[0066] RMPZ molecular sieve: an industrial product produced by Sinopec Catalysts Qilu Branch, with a P2O5 content of 6.85% by weight, a Fe2O3 content of 1.92% by weight, a crystallinity of 70%, a rare earth content of 2% by weight, and the rare earth element being La.

[0067] SLA is a catalytic cracking catalyst produced by Sinopec Catalyst Qilu Branch.

[0068] Boehmite is an industrial product manufactured by Shandong Aluminum Company, with a solid content of 60% by weight.

[0069] The aluminum sol is an industrial product produced by Sinopec Catalyst Qilu Branch, with an Al2O3 content of 21.5% by weight.

[0070] The kaolin is a special kaolin for catalytic cracking catalysts produced by Suzhou Kaolin Company, with a solid content of 78% by weight.

[0071] Hydrochloric acid: chemically pure, concentration 36-38% by weight, produced by Beijing Chemical Plant.

[0072] Phosphoric acid: chemically pure, concentration 85% by weight, produced by Beijing Chemical Plant.

[0073] Preparation Examples 1-4 are examples of the preparation of the aluminum phosphate gel disclosed herein.

[0074] Preparation Example 1

[0075] (1) Mix 2.50 kg (on a dry basis) of boehmite with 5.42 kg of water at 20°C and stir for 30 min. Add 7.31 kg of phosphoric acid, then heat to 70°C. After the temperature stabilizes at 70°C, continue stirring for 90 min to obtain a transparent colloid.

[0076] (2) 0.43 kg of aluminum stone was slurryed, 39 mL of hydrochloric acid was added for acidification, and the mixture was stirred for 30 min to obtain acidified aluminum stone gel. The acidified aluminum stone gel was mixed with the transparent colloid obtained in step (1), and the mixture was stirred and reacted at 70 °C for 30 min to obtain aluminum phosphate gel P-1.

[0077] The material proportions are shown in Table 1.

[0078] Preparation Examples 2-4

[0079] The same method as in Preparation Example 1 was used to prepare aluminum phosphate gel, except that the raw materials and their amounts were different. The specific material ratios are shown in Table 1.

[0080] Preparation of Comparative Example 1

[0081] At room temperature (25℃), 2.5 kg of pseudoboehmite and 5.42 kg of decationized water were mixed and slurried for 30 minutes. 7.31 kg of concentrated phosphoric acid (85% by mass) was added to the slurry while stirring. The temperature was raised to 70℃ and then reacted at this temperature for 45 minutes to obtain the phosphorus aluminum inorganic binder DPAL-1.

[0082] Table 1

[0083]

[0084] Examples 1-5 are examples of the preparation of the catalytic compositions disclosed herein.

[0085] Example 1

[0086] S1. Take RMPZ molecular sieve, add decationized water and slurry for 10 min, then slurry for 120 min to obtain molecular sieve slurry; add kaolin, alumina sol and pseudoboehmite to decationized water and slurry for 20 min, add molecular sieve slurry while stirring, add hydrochloric acid to adjust the pH of the slurry to 3.0, and then continue slurrying for 45 min to obtain the first slurry;

[0087] S2. Add the aluminum phosphate gel to the first slurry prepared in step S1, stir for 5 minutes, spray dry the resulting slurry, and calcine the resulting microspheres at 500℃ for 2 hours to obtain CAT-1. The proportions are shown in Table 2.

[0088] Examples 2-5

[0089] The catalytic composition was prepared using the same method as in Example 1, except that the raw materials used and their amounts were different. The specific proportions are shown in Table 2.

[0090] Comparative Example 1

[0091] Take MPZ molecular sieve, kaolin and bauxite, add decationized water and alumina sol and slurry for 120 minutes. Add hydrochloric acid to adjust the pH of the slurry to 3.0, and continue slurrying for 45 minutes. Then add phosphorus aluminum inorganic binder (DPAL-1), stir for 5 minutes, and spray dry the resulting slurry to obtain microspheres. Calcine the microspheres at 500℃ for 1 hour to obtain DCAT-1. The material ratio is shown in Table 2.

[0092] Comparative Example 2

[0093] The catalytic composition was prepared using the same method as in Example 2, except that the highly active aluminum phosphate binder P-2 was replaced with aluminum phosphate inorganic binder DPAL-1. The material ratios are shown in Table 2.

[0094] Comparative Example 3

[0095] The catalytic composition was prepared using the same method as in Example 2, except that an equal amount of MPZ molecular sieve was used instead of RMPZ molecular sieve.

[0096] Table 2

[0097]

[0098] Compared with the comparative example, the wear index of the catalytic composition disclosed herein is significantly reduced, and its strength is significantly increased.

[0099] Test case

[0100] The following examples use a fixed fluidized bed reactor to illustrate the cracking reaction effect of the cracking catalyst provided by the present invention.

[0101] The catalytic cracking catalyst SLA, along with 30 grams each of CAT-1~4 and DCAT1~2, were aged for 17 hours at 800℃ under a 100% steam atmosphere. Different amounts of the aged catalyst were mixed with SLA (main properties shown in Table 3), and the catalyst mixtures were loaded into a reactor of a small fixed fluidized bed reactor to catalytically crack the feedstock oil shown in Table 4. Table 5 shows the reaction conditions and results.

[0102] Table 3 Main Properties of SLA

[0103] project numerical values Crystallinity, % (w) 15 <![CDATA[BET specific surface area, m 2 / g]]> 181 <![CDATA[Al2O3,%(W)]]> 53.8 <![CDATA[SiO2,%(W)]]> 37.9 <![CDATA[Na2O,%(W)]]> 0.071 <![CDATA[Fe2O3,%(W)]]> 0.629 <![CDATA[P2O5,%(W)]]> 0.505 <![CDATA[Re2O3,%(W)]]> 4.32 Pore ​​volume, mL / g 0.36 Wear index, weight % / h 1.8 Apparent loose density, g / mL 0.75 Microreactivity index (800℃ / 17h), % by weight 62

[0104] Table 4 Evaluation of Crude Oil Properties

[0105]

[0106]

[0107] Table 5 Evaluation Results

[0108]

[0109]

[0110] As can be seen from Table 5, compared with the reference catalytic composition, the catalytic composition provided in this disclosure can effectively increase the propylene content and propylene concentration in catalytic cracking liquefied gas while maintaining a high total yield of gasoline and LPG.

[0111] The preferred embodiments of this disclosure have been described in detail above. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0112] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0113] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A catalytic composition for increasing propylene concentration at high light liquid yields, said catalytic composition comprising rare earth-modified MFI molecular sieves, aluminum phosphate gel, other inorganic binders, and clay; Based on the dry weight of the catalytic composition, the content of the rare earth-modified MFI molecular sieve is 10-65% by weight, the content of the other inorganic binders (calculated as oxides) is 1-25% by weight, the content of the clay is 0-30% by weight, and the content of the aluminum phosphate gel (calculated as P2O5 and Al2O3) is 3-40% by weight. The rare earth content in the rare earth-modified MFI molecular sieve is 0.5-8% by weight, and the rare earth is calculated as rare earth oxides; the rare earth-modified MFI molecular sieve contains a first phosphorus component, and the phosphorus aluminum colloid contains a second phosphorus component. Based on the dry weight of the catalytic composition, the total content of the first phosphorus component and the second phosphorus component, calculated as P2O5, is 10-35% by weight, and the second phosphorus component accounts for 50-95% by weight of the total phosphorus content. The phosphorus aluminum gel is prepared by a method comprising the following steps: (1) At 25-90℃, the first aluminum source and water are mixed and pulped, and the resulting slurry is mixed and stirred with concentrated phosphoric acid to obtain a transparent colloid; (2) At 25-50℃, the second aluminum source is mixed and reacted with the transparent colloid to obtain the phosphorus aluminum glue.

2. The catalytic composition according to claim 1, wherein, The wear index of the catalytic composition is 0-2.5% / h.

3. The catalytic composition according to claim 1, wherein, Based on the dry weight of the phosphorus aluminum gel, the phosphorus aluminum gel contains 10-40% by weight of Al2O3 and 60-90% by weight of P2O5.

4. The catalytic composition according to claim 1, wherein, Based on the dry weight of the catalytic composition, the content of the rare earth-modified MFI molecular sieve is 15-63% by weight, the content of the other inorganic binders (calculated as oxides) is 2-20% by weight, the content of the clay is 1-15% by weight, and the content of the aluminum phosphate gel is 8-35% by weight. The rare earth content in the rare earth-modified MFI molecular sieve is 1-6% by weight.

5. The catalytic composition according to claim 1, wherein, Based on the dry weight of the catalytic composition, the total content of the first phosphorus component and the second phosphorus component, calculated as P2O5, is 15-32% by weight, and the second phosphorus component accounts for 60-90% by weight of the total phosphorus content.

6. The catalytic composition according to claim 1, wherein, The other inorganic binder is selected from one or more of boehmite, alumina, aluminum sol, silica-alumina sol, and silica sol. The clay is selected from one or more of kaolin, sepiolite, attapulgite, rettoite, montmorillonite, and diatomite. The rare earth modified MFI molecular sieve is selected from phosphorus- and rare earth-containing MFI molecular sieves, and / or phosphorus-, rare earth-, and transition metal-containing MFI molecular sieves, wherein the transition metal is a transition metal other than rare earth.

7. The catalytic composition according to claim 6, wherein, In the phosphorus- and rare earth-containing MFI molecular sieve, the content of the first phosphorus component, calculated as P2O5, is 0.5-10% by weight, and the content of rare earth, calculated as RE2O3, is 0.5-8% by weight.

8. The catalytic composition according to claim 6, wherein, The MFI molecular sieve containing phosphorus, rare earth and transition metals contains 0.5-10% by weight of transition metal elements as oxides, 0.5-10% by weight of the first phosphorus component as P2O5, and 0.5-8% by weight of rare earth elements as RE2O3.

9. The catalytic composition according to claim 6, wherein, The transition metal is one or more of Fe, Co, or Ni.

10. The catalytic composition according to claim 1, wherein, In step (1), the weight ratio of the first aluminum source to the concentrated phosphoric acid is 100:(200-700), where the first aluminum source is calculated as alumina and the concentrated phosphoric acid is calculated as phosphorus oxide. In step (2), the weight ratio of the second aluminum source to the amount of the transparent colloid is 100:(500-2000), and the second aluminum source is calculated as aluminum oxide.

11. A method for preparing the catalytic composition according to any one of claims 1-10, the method comprising: S1. Mix the rare earth modified MFI molecular sieve, the other inorganic binder, the clay and water to form a slurry, and adjust the pH value of the slurry to be greater than 2.5 to obtain the first slurry; S2. The first slurry is mixed with the aluminum phosphate gel and then spray-dried and calcined to obtain the catalytic composition.

12. The method according to claim 11, wherein, The first aluminum source is selected from one or more of gibbsite, boehmite, boehmite, pseudoboehmite, and aluminum sol; the second aluminum source is one or more of alumina gel, alumina sol, and aluminum sol.

13. A method for catalytic conversion of hydrocarbon oil, the method comprising: The hydrocarbon oil is reacted with a catalyst, said catalyst containing the catalytic composition according to any one of claims 1-10.

14. The method according to claim 13, wherein, The reaction conditions include: a temperature of 400-700°C and a weight hourly space velocity of 8-120 h⁻¹. -1 The weight ratio of the agent to oil is 1-20.

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