Method for producing ethylene and propylene through catalytic conversion of diesel oil

Abstract

The invention provides a method for producing ethylene and propylene by catalytic conversion of diesel oil, which takes diesel oil as a raw material, adopts a specific process route and is combined with a semi-regenerated catalyst containing a certain amount of carbon deposit to be in contact reaction with the diesel oil, and a strong acid center on the surface of the semi-regenerated catalyst is covered, so that the excessive cracking of the diesel oil is reduced; meanwhile, a catalyst which is subjected to light petroleum hydrocarbon reaction, forms slight carbon deposit and contains a modified MSE structure molecular sieve and an MTT structure molecular sieve is introduced into the second reaction zone of the riser, so that the hydrogen transfer activity and the carbon deposit content of the catalyst in the reaction zone of the riser are adjusted; the generated propylene is prevented from being further saturated into propane by a hydrogen transfer reaction, the propylene selectivity is improved, and the catalyst has relatively high ethylene-propylene selectivity and propylene yield.

Description

Technical Field

[0001] This invention belongs to the field of catalytic cracking, specifically relating to a method for the catalytic conversion of diesel fuel to produce ethylene and propylene. Background Technology

[0002] In recent years, with the continuous development of the chemical industry, the demand for low-carbon olefins such as ethylene and propylene has shown a rapid growth trend, resulting in a significant market gap for low-carbon olefins. Currently, the main methods for producing low-carbon olefins include steam cracking, catalytic cracking, propane dehydrogenation to propylene, and coal-to-methanol reprocessing to olefins. Among these, catalytic cracking offers advantages such as flexible operation, wide availability of raw materials, low energy consumption, and low production costs, and it can produce a significant amount of low-carbon olefins. However, conventional catalytic cracking diesel processes have low low-carbon olefin yields, making it difficult to meet market demand. Therefore, developing catalytic cracking technologies that can process diesel fuel and produce high yields of low-carbon olefins is essential.

[0003] For example, Chinese patent document CN115992007A discloses a method and reactor for the catalytic conversion of diesel oil and catalytic feedstock to produce low-carbon olefins and aromatics. The catalytic feedstock undergoes catalytic cracking in a first reactor, while the diesel oil undergoes catalytic cracking in a second reactor. This allows diesel oil, especially straight-run diesel oil, and catalytic cracking feedstock to react independently in their respective reactors to produce low-carbon olefins and aromatics. However, this method does not specify the type of catalyst used, and the yields of ethylene and propylene are only 4.3% and 20%, respectively. Chinese patent document CN111607425A discloses a method for the catalytic cracking of straight-run diesel oil. Acidic substances are added to the straight-run diesel oil for pretreatment to remove basic nitrogen oxides. A ZSM-5 nanomolecular sieve catalyst is placed in a reactor for pretreatment. Straight-run diesel oil and an inert dilution gas are simultaneously introduced into the reactor to carry out the catalytic cracking reaction, producing low-carbon olefins. However, the yield of low-carbon olefins obtained by this method is low, only 20%-34.31%.

[0004] Current catalytic cracking technologies generally use the same catalyst, but it is difficult to simultaneously meet the secondary cracking requirements of small molecules in diesel fuel. Even when using Y-type molecular sieves and ZSM-5 molecular sieve catalysts, in practical applications, these two catalysts are often directly mixed, causing both catalysts to react with diesel fuel simultaneously. This leads to pore blockage of the ZSM-5 molecular sieve, severely reducing its shape-selective cracking function and resulting in a decrease in the secondary cracking reaction of diesel fuel on the ZSM-5 molecular sieve, as well as a decline in the selectivity of low-carbon olefins. For example, Chinese patent document CN106147832A discloses a selective reaction regeneration process for catalytic cracking. This process involves feeding a semi-regenerated catalyst into a first reactor for a relatively mild cracking reaction, and then feeding a regenerated catalyst into a second reactor for a more demanding cracking reaction. By employing two-stage regeneration and optimizing the operating conditions required for each stage of regeneration, two catalysts with different carbon contents are provided. The carbon on the catalyst is used to adjust and cover the active sites of the catalyst to achieve the required cracking activity, thus meeting the needs of different selective cracking environments. However, using the same catalyst to react with feedstock oil, and using a semi-regenerated catalyst containing carbon deposits to react with light fractions such as diesel under relatively mild cracking conditions, makes it difficult to meet the reaction requirements of different oil products.

[0005] To address the aforementioned issues, some catalytic cracking processes employ two different catalysts to catalytically crack different feedstocks or intermediate products. However, this requires installing a baffle in the stripper to divide it into two independent stripping zones, and installing a baffle in the regenerator to divide it into two independent regeneration zones, making the equipment more complex.

[0006] For example, Chinese patent document CN110317629A discloses a method and apparatus for dual-catalyst partitioned catalytic cracking. By installing a first and second partition inside the middle section of the regenerator, the regenerator is divided into an A catalyst storage chamber, a B catalyst storage chamber, and a catalyst regeneration chamber. An A catalyst primary swirl separator is installed inside the A catalyst storage chamber. The inlet of the A catalyst primary swirl separator is connected to the catalyst regeneration chamber via a pipe passing through the second partition. An opening at the bottom of the A catalyst primary swirl separator connects to the A catalyst storage chamber. A B catalyst primary swirl separator is installed inside the B catalyst storage chamber. The regenerated A catalyst, rich in A catalyst, reacts with heavy feedstock oil in the main reactor, while the regenerated B catalyst, rich in B catalyst, reacts with light feedstock oil in the auxiliary reactor. Although this method increases the yield of low-carbon olefins by 3.92 wt%–5.08 wt%, and reduces the yields of by-product dry gas and coke by 1.65 wt%–2.21 wt% and 1.08 wt%–1.37 wt%, respectively, the regenerator design is relatively complex and its operation is difficult. Summary of the Invention

[0007] In view of this, the present invention provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene. This method uses diesel fuel as feedstock and employs a semi-regenerated catalyst containing a certain amount of coke to react with the diesel fuel. The strong acid centers on the surface of the semi-regenerated catalyst are covered, reducing excessive cracking of the diesel fuel and thus reducing the yield of methane and coke. Simultaneously, by introducing a catalyst containing modified MSE and MTT molecular sieves that has undergone the reaction of light petroleum hydrocarbons and formed slight coke deposits into the second reaction zone of the riser, the hydrogen transfer activity and coke content of the catalyst in the riser reaction zone are adjusted, preventing the generated propylene from being further saturated into propane by hydrogen transfer reactions, thereby improving propylene selectivity and achieving high ethylene-propylene selectivity and propylene yield.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] A method for the catalytic conversion of diesel fuel to produce ethylene and propylene includes the following steps:

[0010] S1: Diesel fuel reacts with catalyst A in reaction zone I of the riser reactor. The resulting first oil-catalyst mixture enters reaction zone II of the riser reactor and reacts with catalyst B. The resulting second oil-catalyst mixture is separated to obtain first oil-gas and mixed carbon deposit catalyst. The first oil-gas is further separated (to obtain methane, ethane, ethylene, propane, propylene, C4-C6). 12 The mixture of non-aromatic components, heavy gasoline, cracked diesel and slurry oil (the specific composition of the separated products can be adjusted as needed) enters the settling tank;

[0011] S2: C4~C4 obtained after the first oil-gas separation 12 Non-aromatic components react with catalyst A in a fluidized bed reactor to obtain a third oil-agent mixture. After separation, a second oil-gas and carbon-depositing catalyst A are obtained. The carbon-depositing catalyst A enters the second reaction zone to react with catalyst B and the first oil-agent mixture. The second oil-gas is mixed with the first oil-gas and then separated.

[0012] S3: The mixed carbon deposition catalyst and the carbon deposition catalyst A in the settling tank are stripped and then enter the regenerator for semi-regeneration. The resulting mixed semi-regenerated catalyst is recycled into the first reaction zone and the fluidized bed reactor to replace the catalyst A.

[0013] The catalyst B includes a modified MSE molecular sieve and an MTT molecular sieve.

[0014] The catalyst A includes Y-type molecular sieves, molecular sieves with modified MSE structure, and molecular sieves with MTT structure;

[0015] The carbon deposition content of the mixed semi-regenerated catalyst, based on 100% by mass, is 0.05%-0.3%, preferably 0.1%-0.25%.

[0016] The first oil-catalyst mixture described above includes the oil vapor generated from the reaction of diesel fuel and catalyst A in reaction zone I, and catalyst A containing carbon deposits. The second oil-catalyst mixture includes the first oil-catalyst mixture and catalyst B containing carbon deposits, or includes the first oil-catalyst mixture, catalyst B containing carbon deposits, and catalyst A containing carbon deposits introduced through the fluidized bed reactor.

[0017] In one optional embodiment, within the first reaction zone, the weight ratio (catalyst-to-oil ratio) of the catalyst A to the diesel fuel is 15:1 to 40:1; preferably 20:1 to 35:1.

[0018] In one optional embodiment, the temperature of the contact reaction between the catalyst A and the diesel oil in the first reaction zone is 655–745°C (preferably 660–740°C), and the time is 0.7–2.0 s.

[0019] In one optional embodiment, the outlet reaction temperature of the first reaction zone is 638–730°C, preferably 645–720°C.

[0020] In one optional embodiment, the diesel fuel enters the first reaction zone at a temperature of 150–250°C.

[0021] In one optional embodiment, the mass ratio of catalyst B to catalyst A entering the first reaction zone is 0.08 to 0.44.

[0022] In one optional embodiment, the weight ratio of the carbon deposition catalyst A entering the second reaction zone from the fluidized bed reactor to the carbon deposition catalyst A in the first oil mixture is 0.1 to 0.4.

[0023] In one alternative embodiment, the mass ratio of catalyst B to the carbon deposition catalyst A entering the second reaction zone from the fluidized bed reactor is 0.8 to 1.13.

[0024] In one optional embodiment, the residence time of the catalyst B and the first oil mixture in the second reaction zone is 1.5 to 3.2 s; or the residence time of the catalyst B, the carbon-depositing catalyst A entering the second reaction zone from the fluidized bed reactor, and the first oil mixture is 1.5 to 3.2 s.

[0025] In one optional embodiment, the outlet temperature of the second reaction zone is 620–715°C, preferably 640–705°C.

[0026] In one optional embodiment, the catalyst B enters the second reaction zone at a temperature of 643–730°C, preferably 650–720°C.

[0027] In one optional embodiment, the catalyst B undergoes non-mass heat exchange to 643–730°C (preferably 643–730°C) in the regenerator before entering the second reaction zone; preferably, the temperature of the regenerator is 700–770°C.

[0028] In one optional embodiment, within the fluidized bed reactor, catalyst A and C4-C5 are reacted... 12 The weight ratio (agent-to-oil ratio) of the non-aromatic components is 15:1 to 40:1, and the residence time is 1.5 to 4.2 s.

[0029] In one optional embodiment, the C4-C4 mixture within the fluidized bed reactor... 12 The weight ratio of the non-aromatic component to the diesel fuel in the first reaction zone is 0.12 to 0.40.

[0030] In one optional embodiment, the absolute pressure of the reaction pressure (settler pressure) is 0.13–0.4 MPa; preferably 0.20–0.35 MPa.

[0031] In one optional embodiment, the catalyst B, by weight (100%), comprises 1%–38% (dry basis) of a modified MSE-structured molecular sieve, 5%–40% (dry basis) of a MTT-structured molecular sieve, 10%–40% (dry basis) of clay, and 19%–50% (dry basis) of a binder based on oxides. Preferably, it comprises 5%–35% (dry basis) of a modified MSE-structured molecular sieve, 7%–35% (dry basis) of a MTT-structured molecular sieve, 15%–35% (dry basis) of clay, and 25%–45% (dry basis) of a binder based on oxides.

[0032] In one optional embodiment, the catalyst A, by mass of 100%, comprises 1% to 15% Y-type molecular sieve (dry basis), 1% to 30% modified MSE structure molecular sieve (dry basis), 5% to 25% MTT structure molecular sieve (dry basis), 15% to 50% clay (dry basis), and 10% to 45% binder (based on oxides); preferably, it comprises 3% to 12% Y-type molecular sieve (dry basis), 3% to 25% modified MSE structure molecular sieve (dry basis), 8% to 20% MTT structure molecular sieve (dry basis), 20% to 45% clay (dry basis), and 15% to 40% binder (based on oxides).

[0033] In one optional embodiment, the modified MSE structure is derived from phosphorus and transition metal modified MCM-68 molecular sieves and has an MSE topology; preferably, based on the mass of the modified MSE structure molecular sieve as 100%, the phosphorus content is 0.5% to 6%, more preferably 1% to 5%, and the transition metal content is 0.5% to 5%, more preferably 1% to 4%.

[0034] In one alternative embodiment, the transition metal is selected from one or more of iron, zinc, and zirconium.

[0035] In an optional embodiment, the preparation method of the phosphorus and transition metal modified MCM-68 molecular sieve is not limited, and it can be prepared by a method including the following steps:

[0036] MSE molecular sieves are impregnated with a phosphorus-containing compound solution, dried, and calcined to obtain phosphorus-modified MSE molecular sieves; then, the phosphorus-modified MSE molecular sieves are impregnated with transition metal nitrates, dried, and calcined to obtain phosphorus and transition metal modified MCM-68 molecular sieves.

[0037] In one optional embodiment, the preparation method of the phosphorus and transition metal modified MCM-68 molecular sieve specifically includes the following steps:

[0038] First, the phosphorus-containing compound is dissolved in deionized water, and then impregnated with MCM-68 molecular sieve at room temperature for 0.5-3 hours (preferably 1-2 hours). It is then dried in an oven at 80-150°C (preferably 90-130°C) for 5-12 hours, and subsequently calcined in a muffle furnace at 500-650°C (preferably 550-600°C) for 1.5-4 hours (preferably 2-3 hours) to obtain P2O5 modified MCM-68 molecular sieve.

[0039] The transition metal nitrate was dissolved in deionized water and then mixed evenly with the above-mentioned P2O5 modified MCM-68 molecular sieve. The mixture was stirred and impregnated at room temperature for 0.5-3 hours (preferably 1-2 hours), dried in an oven at 80-150°C (preferably 90-130°C) for 5-12 hours, and then calcined in a muffle furnace at 500-650°C (preferably 550-600°C) for 1.5-4 hours (preferably 2-3 hours) to obtain the phosphorus and transition metal modified MCM-68 molecular sieve.

[0040] In one alternative embodiment, the phosphorus-containing compound is selected from one or more of ammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, and phosphoric acid.

[0041] In one alternative embodiment, the transition metal nitrate is selected from one or more of ferric nitrate, zinc nitrate, and zirconium nitrate.

[0042] In one optional embodiment, the catalyst A can be prepared by the following method: mixing and stirring deionized water, clay and binder to prepare a colloid, then adding an acidic substance for sol-gel treatment; then adding a Y-type molecular sieve, a molecular sieve with modified MSE structure and a molecular sieve with MTT structure, mixing and pulping to form a slurry; spray molding the slurry, drying, calcining and curing, and washing with water to obtain catalyst A.

[0043] In one optional embodiment, the catalyst B can be prepared by the following method: mixing and stirring deionized water, clay, and binder to prepare a colloid, then adding an acidic substance for sol-gel treatment; then adding a molecular sieve with a modified MSE structure and a molecular sieve with an MTT structure, mixing and pulping to form a slurry; spray molding the slurry, drying, calcining and curing, and washing with water to obtain catalyst B.

[0044] In one optional embodiment, the process conditions for spray molding are as follows: the temperature of the spray tower furnace is controlled at 450-550°C, and the temperature of the spray exhaust gas is controlled at 200-300°C.

[0045] In one optional embodiment, the molecular sieve with the MTT structure is a molecular sieve with an MTT topology, selected from one or more of ZSM-23, SSZ-32, EU-13, ISI-4 and KZ-I molecular sieves.

[0046] In one alternative embodiment, the Y molecule is screened from one or more of ultrastable Y (USY), rare earth Y (REY), rare earth ultrastable Y (RUSY), NaY, hydrogen Y (HY), and ammonium Y (NH4Y) molecular sieves.

[0047] In one alternative embodiment, the clay is selected from one or more of kaolin, montmorillonite, halloysite, and sepiolite; the binder is selected from one or more of boehmite, silica sol, alumina sol, and silica-alumina sol.

[0048] In one optional embodiment, the diesel fuel is selected from one or more of straight-run diesel fuel, catalytic cracking diesel fuel, hydrocracking diesel fuel, coking diesel fuel, and residue hydrotreated diesel fuel.

[0049] The present invention also provides an apparatus for the catalytic conversion of diesel fuel to produce ethylene and propylene, comprising a riser reactor, a fluidized bed reactor, a regenerator, a settling tank, a first separator, a second separator, and a stripper;

[0050] The riser reactor is provided with a pre-lifting section, a first reaction zone, and a second reaction zone that are interconnected from bottom to top along the vertical direction;

[0051] The fluidized bed reactor is provided with a pre-lifting section and a reaction zone that are interconnected from bottom to top along the vertical direction;

[0052] The bottom of the regenerator is connected to the pre-lifting section of the riser reactor and the pre-lifting section of the fluidized bed reactor, respectively.

[0053] The outlet of the second reaction zone is connected to the regenerator via the first separator, the settling tank, and the stripper in sequence; the outlet of the reaction zone of the fluidized bed reactor is connected to the second reaction zone and the fractionation-absorption-stabilization unit via the second separator; the regenerator is equipped with a catalyst B delivery pipeline that is not connected to it, and the catalyst B delivery pipeline is connected to the second reaction zone.

[0054] In one optional embodiment, the second reaction zone is located in the expansion section inside the riser reactor; preferably, the ratio of the inner diameter of the second reaction zone to the inner diameter of the first reaction zone is 1.2:1 to 2.4:1.

[0055] In one optional embodiment, the angle between the connection point of the inner wall of the first reaction zone and the inner wall of the second reaction zone and the axial line of the riser reactor is 18 to 55 degrees.

[0056] The beneficial effects of this invention are as follows:

[0057] Beneficial Effect 1: The method for producing ethylene and propylene from diesel fuel using the diesel fuel provided by this invention involves setting up a riser reactor and a fluidized bed reactor, and using a mixed semi-regenerated catalyst with diesel fuel and C4-C4 fuels. 12 The non-aromatic component feedstock contact reaction involves introducing all the catalyst, which has undergone the reaction of light petroleum hydrocarbons and formed slight coking in the fluidized bed reactor, into the middle of the second reaction zone of the riser. Simultaneously, catalyst B containing MSE and MTT molecular sieves is introduced into the lower part of the second reaction zone of the riser. This allows the intermediate products of diesel cracking to preferentially react with the MSE and MTT molecular sieves, thus converting C4-C4 hydrocarbons into C4-C4 hydrocarbons. 12 The components are selectively cleaved into lower-carbon olefins, thus achieving the selective cracking of C4–C6 olefins. 12 The selective cracking of components significantly improves the yields of ethylene and propylene. Furthermore, by limiting the ratio of catalyst A to catalyst B in each step, the resulting mixed catalyst to be regenerated can be directly mixed for semi-regeneration, yielding a mixed semi-regenerated catalyst with a specific carbon deposit content that can directly replace catalyst A in diesel fuel and C4-C4 mixtures. 12 Non-aromatic components are reacted separately, and the process is repeated in this way, eliminating the need for complex regeneration equipment.

[0058] Beneficial Effect 2: The method for catalytic conversion of diesel to produce ethylene and propylene provided by this invention, in the second reaction zone of the riser, the proportion of catalyst B containing MSE structure molecular sieve and MTT structure molecular sieve is basically equivalent to the proportion of carbon deposit catalyst A flowing into the second reaction zone of the riser from the fluidized bed reactor. This ensures both the cracking reaction of the carbon deposit catalyst flowing into the second reaction zone of the riser on the unreacted diesel macromolecular hydrocarbons and the enhanced catalytic cracking reaction of gasoline olefins by the MSE structure molecular sieve and MTT structure molecular sieve in catalyst B, further improving the yield of ethylene and propylene.

[0059] Beneficial Effect 3: The method for producing ethylene and propylene from diesel fuel using the diesel fuel catalytic conversion method provided by this invention injects catalyst B containing MSE and MTT molecular sieves, which has undergone heat exchange in the regenerator, into the second reaction zone of the riser. This reduces the catalyst activity and hydrogen transfer reaction activity in the second reaction zone of the riser, preventing the generated propylene from forming propane through hydrogen transfer reaction, thereby further improving propylene selectivity. The method achieves the goal of increasing ethylene and propylene yields and reducing methane and coke yields without requiring major modifications to the regenerator. Attached Figure Description

[0060] Figure 1 The present invention provides an apparatus for the catalytic conversion of diesel fuel to produce ethylene and propylene;

[0061] Figure 2 This is an existing diesel catalytic conversion device for the production of ethylene and propylene.

[0062] Among them, 1 is the riser reactor; 2 is the fluidized bed reactor; 3 is the settling tank; 4 is the first separator; 5 is the stripper; 6 is the pipeline for transporting the spent catalyst; 7 is the regenerator; 8 is the flue gas outlet; 9 is the fluidized bed reactor outlet pipeline; 10 is the pipeline for transporting the carbonized catalyst A; 11, 20, 22 are slide valves; 12 is the diesel inlet; 13, 14 are the pre-lifting medium inlet; and 15 is C4~C 12 16. Non-aromatic component inlet; 17. Oil and gas outlet pipeline; 18. Catalyst A inlet; 19. Catalyst B delivery pipeline; 20. Catalyst delivery pipelines; 21. Fractionation-absorption-stabilization unit; 22. Methane; 23. Ethane; 24. Ethylene; 25. Propane; 26. Propylene; 27. C4-C6 12 Non-aromatic components; 30, heavy gasoline; 31, cracked diesel; 32, slurry oil; 40, air inlet; 41, second separator. Detailed Implementation

[0063] The present invention will now be described in detail through embodiments. It should be noted that the following embodiments are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0064] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0065] Analysis and testing methods:

[0066] The elemental composition of Na2O, Al2O3, SiO2 and other elements in the catalyst was determined by X-ray fluorescence spectrometry (see "Analytical Methods in Petrochemical Industry (RIPP Experimental Methods)", edited by Yang Cuiding et al., Science Press, 1990).

[0067] Specific surface area and pore volume were determined by low-temperature nitrogen adsorption-desorption method; particle size distribution was analyzed by laser particle size analysis (analytical method GB / T19077.1-2008).

[0068] Microreactive activity (MA) evaluation: The method described in NB / SH / T 0952-2017 was used; the specific procedure is as follows:

[0069] The catalyst was pretreated at 800℃ and 100% steam for 17 hours, and then Dagang light diesel oil was used as the reaction feedstock. The reaction temperature was 460℃, the oil inlet time was 70s, the catalyst loading was 5g, and the yield of gasoline after the reaction was analyzed by GC7890.

[0070] The catalyst A, catalyst B, and diesel fuel specified in this invention can all meet the requirements for implementation. However, for ease of comparison, the following raw materials are all from the following sources:

[0071] Molecular sieves with MSE structure (MCM-68 molecular sieve), molecular sieves with MTT structure (ZSM-23 molecular sieve, SSZ-32 molecular sieve), and Y-type molecular sieves were all purchased from Tianjin Nanhua Catalyst Co., Ltd.

[0072] Before evaluation, each catalyst (including the control catalyst) was subjected to hydrothermal deactivation treatment at 800℃ and 100% steam for 10 hours. The physicochemical properties of each catalyst after hydrothermal deactivation treatment are shown in Table 1 and Table 2.

[0073] Table 1 Physicochemical properties of the catalyst

[0074]

[0075]

[0076] Table 2 Physicochemical properties of catalysts

[0077]

[0078] C4~C 12 The non-aromatic component raw material is obtained by separation using this method;

[0079] The diesel fuel used is straight-run diesel fuel from a certain petrochemical company of China National Petroleum Corporation (hereinafter referred to as diesel fuel, properties are shown in Table 3).

[0080] Table 3 Properties of Diesel Oil

[0081]

[0082]

[0083] The raw materials listed above are not intended to limit the present invention. The present invention will be further illustrated by the following examples, but it is not believed that the present invention is limited to these examples.

[0084] Example 1

[0085] This embodiment provides an apparatus for the catalytic conversion of diesel fuel to produce ethylene and propylene, including a riser reactor, a fluidized bed reactor, a regenerator, a settling tank, a first separator, a second separator, and a stripper;

[0086] The riser reactor is vertically arranged from bottom to top as follows: a pre-lifting section, a first reaction zone, and a second reaction zone; the second reaction zone is located in the expansion section inside the riser reactor 1; the pre-lifting section is provided with a pre-lifting medium inlet and a catalyst inlet; a diesel inlet is provided at the connection between the first reaction zone and the pre-lifting section;

[0087] The second reaction zone is equipped with a catalyst B inlet, a carbon-deposited catalyst A inlet, and a second oil-agent mixture outlet;

[0088] The outlet of the second oil mixture is connected to the fractionation-absorption-stabilization unit and the settling tank via the first separator. The settling tank is connected to the regenerator via the stripper and the catalyst delivery pipeline.

[0089] The fluidized bed reactor consists of an interconnected pre-lifting section and a reaction zone arranged vertically from bottom to top. The pre-lifting section is equipped with C4~C4 reactors. 12 The reaction zone has an inlet for non-aromatic components, an inlet for pre-lifting medium, and an inlet for catalyst. The top of the reaction zone has an outlet, which is connected to the fractionation-absorption-stabilization unit and the carbon-deposited catalyst inlet of the second reaction zone via a second separator.

[0090] The bottom of the regenerator is connected via pipelines to the catalyst inlet of the pre-lift section of the riser reactor and the catalyst inlet of the pre-lift section of the fluidized bed reactor, respectively.

[0091] The regenerator is also equipped with a catalyst B delivery pipeline that is connected to the catalyst B inlet of the second reaction zone, but the catalyst B delivery pipeline is not connected to the regenerator.

[0092] Specifically, such as Figure 1 As shown, the apparatus for the catalytic conversion of diesel fuel to produce ethylene and propylene includes a riser reactor 1, a fluidized bed reactor 2, a regenerator 7, a settling tank 3, a first separator 4, a second separator 41, and a stripper 5.

[0093] The riser reactor 1 is vertically arranged from bottom to top as follows: a pre-lifting section, a first reaction zone, and a second reaction zone. The pre-lifting section is provided with a pre-lifting medium inlet 13 and a catalyst inlet. The connection between the first reaction zone and the pre-lifting section is provided with a diesel inlet 12. The second reaction zone is located in the expansion section inside the riser reactor 1. The second reaction zone is provided with a catalyst B inlet, a carbon deposit-containing catalyst inlet, and a second oil-agent mixture outlet.

[0094] The fluidized bed reactor 2 is vertically arranged from bottom to top with interconnected pre-lifting section and reaction zone. The pre-lifting section is equipped with C4~C4 reactors. 12 Non-aromatic component inlet 15, pre-lifting medium inlet 14 and catalyst inlet;

[0095] The bottom of the regenerator 7 is connected to the catalyst inlet of the pre-lift section of the riser reactor 1 via the catalyst delivery pipeline 19; the bottom of the regenerator 7 is connected to the catalyst inlet of the pre-lift section of the fluidized bed reactor 2 via the catalyst delivery pipeline 21; a slide valve 20 is provided on the catalyst delivery pipeline 19, and a slide valve 22 is provided on the catalyst delivery pipeline 21. The slide valves 20 and 22 are used to control the amount of catalyst delivered to the pre-lift section of the riser reactor 1 and the fluidized bed reactor, respectively.

[0096] The regenerator 7 is equipped with a catalyst B delivery pipeline 18 that is connected to the catalyst B inlet of the second reaction zone, but the catalyst B delivery pipeline 18 is not connected to the interior of the regenerator 7; the second oil-agent mixture outlet of the second reaction zone is connected to the first separator 4, and the first separator 4 is connected to the regenerator 7 in sequence via the settling device 3, the stripper 5, and the catalyst delivery pipeline 6.

[0097] The outlet of the reaction zone of fluidized bed reactor 2 is connected to the second separator 41 via fluidized bed reactor outlet pipeline 9. The bottom of the second separator 41 is connected to the inlet of the carbonized catalyst in the second reaction zone via carbonized catalyst conveying pipeline 10. A slide valve 11 is installed on the carbonized catalyst conveying pipeline 10. The top of the second separator 41 is connected to the fractionation-absorption-stabilization unit 23 via oil and gas outlet pipeline 16. The fractionation-absorption-stabilization unit 23 is connected to methane 24, ethane 25, ethylene 26, propane 27, propylene 28, and C4~C4 hydrocarbons, respectively. 12 The pipelines for non-aromatic component 29, heavy gasoline 30, cracked diesel 31, and slurry oil 32 are connected; among them, C4~C 12 Non-aromatic component 29 can pass through the pre-lifting section of fluidized bed reactor 2 (C4-C5). 12 The non-aromatic component is circulated from inlet 15 into fluidized bed reactor 2.

[0098] The regenerator 7 has a catalyst inlet 17 and an air inlet 40 at the bottom and a flue gas outlet 8 at the top.

[0099] The ratio of the inner diameter of reaction zone II to that of reaction zone I is 1.2:1 to 2.4:1, which can be adjusted according to actual needs; the angle between the connection between the inner walls of reaction zone I and reaction zone II and the axial line of riser reactor 1 is 18 to 55 degrees, which can be adjusted according to actual needs.

[0100] Example 2

[0101] This embodiment provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene, employing... Figure 1 The apparatus shown has the following configuration: the total height of the pre-lifting section, reaction zone I, and reaction zone II of the riser reactor is 3.5 meters; the inner diameter of the pre-lifting section is 0.01 meters, and its height is 0.3 meters; the inner diameter of reaction zone I is 0.016 meters, and its height is 1.7 meters; the inner diameter of reaction zone II is 0.0288 meters, and its height is 1.5 meters; the ratio of the inner diameter of reaction zone II to that of reaction zone I is 1.8:1; and the angle between the connection point of the inner walls of reaction zones I and II and the axial line of the riser reactor is 30 degrees. The total height of the fluidized bed reactor is 3.3 meters; the inner diameter of the pre-lifting section is 0.01 meters, and its height is 0.3 meters; the inner diameter of the reaction zone is 0.025 meters, and the height of the reaction zone is 3 meters. The reaction pressure (sedimentation pressure) is 0.21 MPa (absolute pressure).

[0102] Aged catalysts A-1 and B-1 were used as catalysts. After normal operation, mixed semi-regenerated catalyst 1 was used to replace catalyst A-1. The specific steps included:

[0103] Catalyst A-1, after hydrothermal deactivation treatment, is added to regenerator 7 through catalyst A inlet 17. After regenerator 7 is heated to the required conditions for atomizing steam, stripping steam, and feedstock oil, catalyst A-1 is transported to the pre-lifting section through catalyst delivery pipeline 19 and slide valve 20. Then, under the lifting action of nitrogen gas added through pre-lifting medium inlet 13, it moves upward in the pre-lifting section of riser reactor 1 and reacts with diesel fuel (added through diesel inlet 12) preheated at 200℃ and atomized by atomizing steam in the first reaction zone to obtain the first oil-agent mixture. The contact reaction temperature is 745℃, the time is 0.7s, the weight ratio of catalyst A-1 to diesel fuel (agent-to-oil ratio) is 40:1, the weight ratio of atomizing steam to diesel fuel is 0.1, the outlet temperature of the first reaction zone is 730℃, and the reacted catalyst A-1 forms carbon deposit catalyst A-1.

[0104] After hydrothermal deactivation treatment, catalyst B-1 undergoes heat exchange in regenerator 7 and then enters the second reaction zone of riser reactor 1 via catalyst B delivery pipeline 18. The temperature of catalyst B-1 entering the lower part of the second reaction zone is 730℃. It reacts with the first oil-agent mixture obtained from the first reaction zone of riser reactor 1 in the expansion section of the second reaction zone. The second oil-agent mixture obtained after the reaction enters the first separator 4, where it is separated to obtain the first oil-gas and mixed carbonized catalyst. The first oil-gas enters the fractionation-absorption-stabilization unit 23 via oil-gas outlet pipeline 16, where it is separated to obtain methane 24, ethane 25, ethylene 26, propane 27, propylene 28, and C4~C6. 12 Non-aromatic components 29, heavy gasoline 30, cracked diesel 31, and slurry oil 32. The mixed carbon deposit catalyst enters settler 3 for settling and then enters stripper 5. After steam stripping, the resulting spent catalyst enters regenerator 7 via spent catalyst delivery pipeline 6 for semi-regeneration, yielding a semi-regenerated catalyst. The semi-regeneration temperature is 770℃, the regeneration medium enters from air inlet 40, and the regeneration air flow rate is 27 L / min. The regenerated flue gas is discharged from flue gas outlet 8. Oxygen analyzer, CO analyzer, and CO2 analyzer are used to analyze the flue gas, with O2, CO, and CO2 concentrations of 0%, 1.70%, and 3.10%, respectively.

[0105] Catalyst A-1, after hydrothermal deactivation treatment in regenerator 7, moves upward in the pre-lifting section of fluidized bed reactor 2 via catalyst delivery pipeline 21 and slide valve 22, under the lifting action of pre-lifting medium nitrogen (added through pre-lifting medium inlet 14), and interacts with preheated, atomized C4~C4 catalysts. 12 Non-aromatic components (obtained via fractionation-absorption-stabilization unit 23, C4~C4) 12Non-aromatic components (inlet 15) enter the fluidized bed reactor and react in fluidized bed reactor 2 at a contact temperature of 745℃. The C4-C4 components in fluidized bed reactor 2... 12 The weight ratio of non-aromatic components to diesel fuel in riser reactor 1 is 0.12. Catalyst A-1 and C4~C4 enter fluidized bed reactor 2. 12 The weight ratio of non-aromatic components (co-oil ratio) is 40:1, and the atomized steam contains C4-C4 hydrocarbons. 12 The non-aromatic component has a weight ratio of 0.1, and the residence time of catalyst A-1 with the oil and gas in the fluidized bed reactor is 1.5 s. After the reaction, the mixture of the second oil and gas and the carbonized catalyst A-1 flows into the second separator 41 through the outlet pipeline 9 of the fluidized bed reactor for separation. The separated carbonized catalyst A-1 enters the middle of the second reaction zone in the riser reactor 1 through the carbonized catalyst conveying pipeline 10 and the slide valve 11, where it reacts with the first oil mixture and catalyst B-1 in the second reaction zone. The residence time of the catalyst and oil and gas in the second reaction zone is 1.5 s, and the outlet temperature of the second reaction zone is 710℃. The second oil and gas mixes with the subsequent first oil and gas through the oil and gas outlet pipeline 16 and enters the fractionation-absorption-stabilization unit 23 for separation.

[0106] The weight ratio of the carbon deposit catalyst A-1 that reacts in the fluidized bed reactor 2 and enters the second reaction zone of the riser reactor 1 to the carbon deposit catalyst A-1 in the first oil mixture entering the second reaction zone of the riser reactor 1 is 0.11.

[0107] The mass ratio of catalyst B-1 to catalyst A-1 entering the first reaction zone of the riser is 0.11, and the mass ratio of catalyst B-1 to carbon deposition catalyst A-1 entering the second reaction zone of the fluidized bed reactor 2 is 1.

[0108] The mixed semi-regenerated catalyst obtained from the semi-regeneration process in the regenerator is recycled into the first reaction zone of the riser reactor and the fluidized bed reactor, respectively, to replace catalyst A-1; thus, the various devices and pipelines cooperate to form a stable reaction system. This invention, by adjusting the ratio of the mixed semi-regenerated catalyst to catalyst B-1, can create a catalyst that satisfies the reactions in the first and second reaction zones of the riser reactor and the fluidized bed reactor, without requiring separation of the two catalysts or modification of the equipment. Specific reaction results are shown in Table 4.

[0109] The preparation steps for phosphorus, iron, and zirconium-modified MSE molecular sieves are as follows:

[0110] First, 107.21g of ammonium phosphate trihydrate was dissolved in 7.5kg of deionized water, and then 7.5kg of MCM-68 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-aluminum ratio 30, the same below) was added and stirred and impregnated at room temperature for 0.5h. Then, it was dried in an oven at 80℃ for 12h, and then calcined in a muffle furnace at 500℃ for 4h to obtain P2O5 modified MCM-68 molecular sieve.

[0111] 961.88 g of ferric nitrate nonahydrate and 652.5 g of zirconium nitrate pentahydrate were dissolved in deionized water, and 7.65 kg of P2O5-modified MCM-68 molecular sieve was added. The mixture was stirred and impregnated at room temperature for 0.5 h, dried in an oven at 80 °C for 12 h, and then calcined in a muffle furnace at 500 °C for 4 h to obtain MCM-68 molecular sieve modified with 0.5% P2O5, 2.5% iron oxide and 2.5% zirconium oxide (i.e., phosphorus, iron and zirconium modified MCM-68 molecular sieve).

[0112] The catalyst B-1 described above was prepared using a method comprising the following steps:

[0113] Add 3.9 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 3.846 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 20 kg of deionized water to a pulping tank and pulp. Then add 6.24 kg of boehmite (62.5 wt% solid content, product of Shanxi Aluminum Plant, the same below), stir for 1 hour, then add 453 mL of concentrated hydrochloric acid, stir for 1.5 hours, and then age at 65°C for 1.2 hours.

[0114] 5.7 kg of the above-mentioned phosphorus, iron and zirconium modified MCM-68 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-aluminum ratio 30, the same below), 0.75 kg of ZSM-23 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-aluminum ratio 60, the same below) and 4.667 kg of deionized water were mixed and pulped for 1 hour, and then added to the above-mentioned pulping tank. The pulping was homogenized for 0.5 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 450℃ and the temperature of the spray exhaust gas was controlled at 200℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 500℃ for 4 hours, washed at 50℃ and dried at 80℃ to obtain catalyst B-1.

[0115] Based on the mass of catalyst B-1 (100%), it comprises: 38 wt% phosphorus, iron and zirconium modified MSE structured molecular sieve (MCM-68 molecular sieve) on a dry basis, 5 wt% MTT structured molecular sieve on a dry basis, 26 wt% clay on a dry basis, and 31 wt% binder on an oxide basis (of which 26 wt% is alumina from pseudoboehmite and 5 wt% is alumina from alumina sol).

[0116] The catalyst A-1 described above was prepared using a method comprising the following steps:

[0117] Add 6.75 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 3.077 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 20 kg of deionized water to a pulping tank and pulp. Then add 2.64 kg of pseudoboehmite (62.5 wt% solid content, product of Shanxi Aluminum Plant, the same below), stir for 1 hour, then add 453 mL of concentrated hydrochloric acid, stir for 1.5 hours, and then age at 65°C for 2 hours.

[0118] 0.75 kg of USY molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 11.53, the same below), 4.5 kg of the above-mentioned phosphorus, iron and zirconium modified MCM-68 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 30, the same below), 0.75 kg of ZSM-23 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 60, the same below) and 4.667 kg of deionized water were mixed and pulped for 1 hour, and then added to the above-mentioned pulping tank. The pulping was homogenized for 0.5 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 450℃ and the temperature of the spray exhaust gas was controlled at 200℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 500℃ for 4 hours, washed at 50℃ and dried at 80℃ to obtain catalyst A-1.

[0119] Based on the mass of catalyst A-1 (100%), it comprises: 5% by weight of Y-type molecular sieve (dry basis), 30% by weight of phosphorus, iron and zirconium modified MSE structure molecular sieve (MCM-68 molecular sieve) (dry basis), 5% by weight of MTT structure molecular sieve (dry basis), 45% by weight of clay (dry basis), and 15% by weight of binder (oxides, of which 11% by weight are alumina from boehmite and 4% by weight are alumina from alumina sol).

[0120] The carbon content of the mixed semi-regenerated catalyst obtained above was determined to be 0.30% by an HIR-944B infrared carbon analyzer.

[0121] Example 3

[0122] This embodiment is similar to Embodiment 2, except that some parameters are different. The specific different parameters and results are shown in Table 5.

[0123] In this embodiment, aged catalysts A-2 and B-2 are used. After normal operation, mixed semi-regenerated catalyst 2 is used to replace catalyst A-2. The preparation of catalysts A-2 and B-2 specifically includes the following steps:

[0124] The preparation steps of phosphorus, zinc, and zirconium-modified MSE molecular sieves are as follows:

[0125] First, 428.85g of diammonium hydrogen phosphate was dissolved in 7.5kg of deionized water, and then 7.5kg of MCM-68 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-aluminum ratio 30, the same below) was added. The mixture was stirred and impregnated at room temperature for 1h, dried in an oven at 100℃ for 10h, and then calcined in a muffle furnace at 550℃ for 3h to obtain P2O5 modified MCM-68 molecular sieve.

[0126] 550g of zinc nitrate hexahydrate and 522g of zirconium nitrate pentahydrate were dissolved in deionized water, and then 7.65kg of P2O5-modified MCM-68 molecular sieve was added. The mixture was stirred and impregnated at room temperature for 1 hour, dried in an oven at 100℃ for 10 hours, and then calcined in a muffle furnace at 550℃ for 3 hours to obtain MCM-68 molecular sieve modified with 2% P2O5, 2% zinc oxide and 2% zirconium oxide (i.e., phosphorus, zinc and zirconium modified MCM-68 molecular sieve).

[0127] The catalyst B-2 mentioned above was prepared by a method including the following steps:

[0128] Add 6 kg halloysite (dry basis, provided by Lanzhou Petrochemical Company Catalyst Plant, the same below), 6.154 kg alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 10.333 kg deionized water to a slurry tank and slurry. Then add 2.64 kg boehmite (62.5 wt% solid content, product of Shanxi Aluminum Plant, the same below), stir for 1.5 hours, then add 233 mL concentrated hydrochloric acid, stir for 2 hours, and then age at 70°C for 1 hour.

[0129] 0.15 kg of the above-mentioned phosphorus, zinc and zirconium modified MCM-68 molecular sieve, 6 kg of SSZ-32 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-aluminum ratio 25, the same below) and 8.533 kg of deionized water were mixed and pulped for 1.5 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1 hour. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 475℃ and the temperature of the spray tail gas was controlled at 225℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 550℃ for 3 hours, washed at 60℃ and dried at 100℃ to obtain catalyst B-2.

[0130] Based on the mass of catalyst B-2 (100%), it comprises: 1% by weight of phosphorus, zinc and zirconium modified MSE structured molecular sieve (MCM-68 molecular sieve) on a dry basis, 40% by weight of MTT structured molecular sieve on a dry basis, 40% by weight of clay on a dry basis, and 19% by weight of binder on an oxide basis (of which 11% by weight is alumina from pseudoboehmite and 8% by weight is alumina from alumina sol).

[0131] The catalyst A-2 described above was prepared using a method comprising the following steps:

[0132] Add 5.25 kg halloysite (dry basis, provided by Lanzhou Petrochemical Company Catalyst Plant, the same below), 3.846 kg alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 10.333 kg deionized water to a pulping tank and pulp. Then add 6 kg of pseudoboehmite (62.5 wt% solid content, product of Shanxi Aluminum Plant, the same below), stir for 1.5 hours, then add 233 mL of concentrated hydrochloric acid, stir for 2 hours, and then age at 70°C for 1.2 hours.

[0133] 0.15 kg of REY molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., lanthanum oxide content 2%, silicon-to-aluminum ratio 11.53, the same below), 3.75 kg of the above-mentioned phosphorus, zinc and zirconium modified MCM-68 molecular sieve, 1.35 kg of ZSM-23 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 60, the same below) and 8.533 kg of deionized water were mixed and pulped for 1.5 hours, then added to the above pulping tank, and pulped and homogenized for 1 hour. The spray drying conditions were controlled to obtain catalyst microspheres. The furnace temperature of the spray tower was controlled at 475℃ and the spray tail gas temperature was controlled at 225℃. The catalyst microspheres obtained by spray drying were calcined at 550℃ for 3 hours, washed at 60℃ and dried at 100℃ to obtain catalyst A-2.

[0134] Based on the mass of catalyst A-2 (100%), it comprises: 1% by weight of Y-type molecular sieve (dry basis), 25% by weight of phosphorus, zinc and zirconium modified MSE structure molecular sieve (MCM-68 molecular sieve) (dry basis), 9% by weight of MTT structure molecular sieve (dry basis), 35% by weight of clay (dry basis), and 30% by weight of binder (oxides, of which 25% by weight are alumina from boehmite and 5% by weight are alumina from alumina sol).

[0135] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 0%, 1.50%, and 1.68%, respectively.

[0136] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer, and the carbon content of the mixed semi-regenerated catalyst obtained above was 0.26%.

[0137] Example 4

[0138] This embodiment is similar to Embodiment 2, except that some parameters are different. The specific different parameters and results are shown in Table 5.

[0139] In this embodiment, aged catalysts A-3 and B-3 are used. After normal operation, mixed semi-regenerated catalyst 3 is used to replace catalyst A-3. The preparation of catalysts A-3 and B-3 specifically includes the following steps:

[0140] The preparation steps of phosphorus and zirconium-modified MSE molecular sieves are as follows:

[0141] First, 643.28 g of ammonium dihydrogen phosphate was dissolved in 7.5 kg of deionized water. Then, 7.5 kg of MCM-68 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 30, the same below) and the ammonium dihydrogen phosphate deionized water solution were placed in a slurry tank and stirred and impregnated at room temperature for 1.5 h. After that, it was dried in an oven at 120 ℃ for 9 h, and then calcined in a muffle furnace at 570 ℃ for 2.5 h to obtain P2O5 modified MCM-68 molecular sieve.

[0142] 643.28 g of zirconium nitrate pentahydrate was dissolved in deionized water. Then, 7.65 kg of P2O5-modified MCM-68 molecular sieve was mixed evenly with zirconium nitrate pentahydrate and placed in a pulping tank. The mixture was stirred and impregnated at room temperature for 1.5 h, dried in an oven at 120 °C for 9 h, and then calcined in a muffle furnace at 570 °C for 2.5 h to obtain MCM-68 molecular sieve modified with 3% P2O5 and 3% zirconium oxide.

[0143] The catalyst B-3 described above was prepared using a method comprising the following steps:

[0144] 1.35 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 0.15 kg of montmorillonite (dry basis, Shanghai Aladdin Biochemical Technology Co., Ltd., the same below), 7.692 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 8.9 kg of deionized water were added to a pulping tank and pulped. Then, 9.6 kg of pseudoboehmite (solid content 62.5 wt%, product of Shanxi Aluminum Plant, the same below) was added and stirred for 0.5 hours. Then, 133 mL of concentrated hydrochloric acid was added and stirred for 0.5 hours. After that, the mixture was aged at 55°C for 2 hours.

[0145] 2.85 kg of the above-mentioned phosphorus and zirconium modified MCM-68 molecular sieve, 3.15 kg of ZSM-23 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 60, the same below) and 9.467 kg of deionized water were mixed and pulped for 1.2 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1.4 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 500℃ and the temperature of the spray exhaust gas was controlled at 250℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 570℃ for 2.5 hours, washed at 65℃ and dried at 120℃ to obtain catalyst B-3.

[0146] Based on the mass of catalyst B-3 (100%), it comprises: 19 wt% phosphorus and zirconium-modified MCM-68 molecular sieve (dry basis), 21 wt% MTT structured molecular sieve (dry basis), 10 wt% clay (dry basis), and 50 wt% binder (oxides, of which 40 wt% is alumina from boehmite and 10 wt% is alumina from alumina sol).

[0147] The catalyst A-3 described above was prepared using a method comprising the following steps:

[0148] 6.75 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 0.75 kg of montmorillonite (dry basis, Shanghai Aladdin Biochemical Technology Co., Ltd., the same below), 3.846 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 8.9 kg of deionized water were added to a pulping tank and pulped. Then 1.2 kg of pseudoboehmite (solid content 62.5 wt%, product of Shanxi Aluminum Plant, the same below) was added and stirred for 0.5 hours. Then 133 mL of concentrated hydrochloric acid was added and stirred for 0.5 hours. After that, the mixture was aged at 55°C for 2 hours.

[0149] 2.25 kg of RUSY molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., cerium oxide content 3%, silicon-to-aluminum ratio 11.53, the same below), 0.15 kg of the above-mentioned phosphorus and zirconium modified MCM-68 molecular sieve, 3.6 kg of ZSM-23 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 60, the same below) and 9.467 kg of deionized water were mixed and pulped for 0.5 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1.8 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 500℃ and the temperature of the spray exhaust gas was controlled at 250℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 570℃ for 2.5 hours, washed at 65℃ and dried at 120℃ to obtain catalyst A-3.

[0150] Based on the mass of catalyst A-3 as 100%, it comprises: 15% by weight of Y-type molecular sieve on a dry basis, 1% by weight of phosphorus and zirconium modified MCM-68 molecular sieve on a dry basis, 24% by weight of MTT structured molecular sieve on a dry basis, 50% by weight of clay on a dry basis, and 10% by weight of binder on an oxide basis (of which 5% by weight is alumina from boehmite and 5% by weight is alumina from alumina sol).

[0151] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer, with O2, CO, and CO2 concentrations of 0%, 0.9%, and 2.05%, respectively.

[0152] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer, and the carbon content of the mixed semi-regenerated catalyst obtained above was 0.05%.

[0153] Example 5

[0154] This embodiment is similar to Embodiment 2, except that some parameters are different. The specific different parameters and results are shown in Table 5.

[0155] In this embodiment, aged catalysts A-4 and B-4 are used. After normal operation, mixed semi-regenerated catalyst 4 is used to replace catalyst A-4. The preparation of catalysts A-4 and B-4 specifically includes the following steps:

[0156] The preparation steps of phosphorus and iron modified MCM-68 molecular sieves are as follows:

[0157] First, 1072.13g of phosphoric acid was dissolved in 7.5kg of deionized water. Then, 7.5kg of MCM-68 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 30, the same below) and the deionized phosphoric acid aqueous solution were placed in a slurry tank and stirred and impregnated at room temperature for 2h. After that, it was dried in an oven at 140℃ for 7h, and then calcined in a muffle furnace at 600℃ for 2h to obtain P2O5 modified MCM-68 molecular sieve.

[0158] 384.75 g of ferric nitrate nonahydrate was dissolved in deionized water. Then, 7.65 kg of P2O5-modified MCM-68 molecular sieve was mixed evenly with ferric nitrate nonahydrate and placed in a pulping tank. The mixture was stirred and impregnated at room temperature for 2 hours, dried in an oven at 140℃ for 7 hours, and then calcined in a muffle furnace at 600℃ for 2 hours to obtain MCM-68 molecular sieve modified with 5% P2O5 and 1% iron oxide.

[0159] The catalyst B-4 described above was prepared using a method comprising the following steps:

[0160] 4.56 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 0.24 kg of sepiolite (dry basis, industrial product of Hubei Shixing Chemical Co., Ltd., the same below), 3.077 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 19 kg of deionized water were added to a pulping tank and pulped. Then 5.28 kg of pseudoboehmite (solid content 62.5 wt%, product of Shanxi Aluminum Plant, the same below) was added and stirred for 2 hours. Then 500 mL of concentrated hydrochloric acid was added and stirred for 1.2 hours. After that, the mixture was aged at 60°C for 1.4 hours.

[0161] 4.05 kg of the above-mentioned phosphorus and iron modified MCM-68 molecular sieve, 2.25 kg of SSZ-32 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-aluminum ratio 25, the same below) and 8.333 kg of deionized water were mixed and pulped for 2 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1.2 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 525℃ and the temperature of the spray exhaust gas was controlled at 275℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 600℃ for 2 hours, washed at 70℃ and dried at 140℃ to obtain catalyst B-4.

[0162] Based on the mass of catalyst B-4 as 100%, it comprises: 27 wt% phosphorus and iron modified MCM-68 molecular sieve on a dry basis, 15 wt% MTT structured molecular sieve on a dry basis, 32 wt% clay on a dry basis, and 26 wt% binder on an oxide basis (of which 22 wt% is alumina from boehmite and 4 wt% is alumina from alumina sol).

[0163] The catalyst A-4 described above was prepared using a method comprising the following steps:

[0164] 4.28 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 0.22 kg of sepiolite (dry basis, industrial product of Hubei Shixing Chemical Co., Ltd., the same below), 4.615 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 19 kg of deionized water were added to a pulping tank and pulped. Then 5.28 kg of pseudoboehmite (solid content 62.5 wt%, product of Shanxi Aluminum Plant, the same below) was added and stirred for 1.2 hours. Then 500 mL of concentrated hydrochloric acid was added and stirred for 1.4 hours. After that, the mixture was aged at 50°C for 1.6 hours.

[0165] 1.05 kg of HY molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 11.25, the same below), 1.5 kg of the above-mentioned phosphorus and iron modified MCM-68 molecular sieve, 3.75 kg of SSZ-32 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 25, the same below) and 8.333 kg of deionized water were mixed and pulped for 1.2 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1.4 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 525℃ and the temperature of the spray exhaust gas was controlled at 275℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 600℃ for 2 hours, washed at 70℃ and dried at 140℃ to obtain catalyst A-4.

[0166] Based on the mass of catalyst A-4 as 100%, it comprises: 7% by weight of Y-type molecular sieve on a dry basis, 10% by weight of phosphorus and iron modified MCM-68 molecular sieve on a dry basis, 25% by weight of MTT structured molecular sieve on a dry basis, 30% by weight of clay on a dry basis, and 28% by weight of binder on an oxide basis (of which 22% by weight is alumina from boehmite and 6% by weight is alumina from alumina sol).

[0167] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 0%, 1.30%, and 1.96%, respectively.

[0168] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer, and the carbon content of the mixed semi-regenerated catalyst obtained above was 0.22%.

[0169] Example 6

[0170] This embodiment is similar to Embodiment 2, except that some parameters are different. The specific different parameters and results are shown in Table 5.

[0171] In this embodiment, aged catalysts A-5 and B-5 are used. After normal operation, mixed semi-regenerated catalyst 5 is used to replace catalyst A-5. The preparation of catalysts A-5 and B-5 specifically includes the following steps:

[0172] The preparation steps of phosphorus and zinc modified MCM-68 molecular sieve are as follows:

[0173] First, 1072.13g of ammonium phosphate trihydrate was dissolved in 7.5kg of deionized water. Then, 7.5kg of MCM-68 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 30, the same below) and the deionized water solution of ammonium phosphate trihydrate were placed in a slurry tank and stirred and impregnated at room temperature for 3h. After that, it was dried in an oven at 150℃ for 5h, and then calcined in a muffle furnace at 650℃ for 1.5h to obtain P2O5 modified MCM-68 molecular sieve.

[0174] 137.5 g of zinc nitrate hexahydrate was dissolved in deionized water. Then, 7.65 kg of P2O5-modified MCM-68 molecular sieve was mixed evenly with zinc nitrate hexahydrate and placed in a pulping tank. The mixture was stirred and impregnated at room temperature for 3 h, then dried in an oven at 150 °C for 5 h, and finally calcined in a muffle furnace at 650 °C for 1.5 h to obtain MCM-68 molecular sieve modified with 5% P2O5 and 0.5% zinc oxide.

[0175] The catalyst B-5 described above was prepared using a method comprising the following steps:

[0176] 2.04 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 0.51 kg of halloysite (dry basis, provided by Lanzhou Petrochemical Company Catalyst Plant, the same below), 12.308 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 13.333 kg of deionized water were added to a slurry tank and slurried. Then 5.76 kg of pseudoboehmite (solid content 62.5 wt%, product of Shanxi Aluminum Plant, the same below) was added and stirred for 1.2 hours. Then 363 mL of concentrated hydrochloric acid was added and stirred for 1.4 hours. After that, the mixture was aged at 50°C for 1.6 hours.

[0177] 1.65 kg of the above-mentioned phosphorus and zinc modified MCM-68 molecular sieve, 4.8 kg of ZSM-23 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-aluminum ratio 60, the same below) and 8 kg of deionized water were mixed and pulped for 0.5 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1.8 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 550℃ and the temperature of the spray exhaust gas was controlled at 300℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 650℃ for 1.5 hours, washed at 80℃ and dried at 150℃ to obtain catalyst B-5.

[0178] Based on the mass of catalyst B-5 (100%), it comprises: 11% by weight of phosphorus and zinc modified MCM-68 molecular sieve (dry basis), 32% by weight of MTT structured molecular sieve (dry basis), 17% by weight of clay (dry basis), and 40% by weight of binder (oxides, of which 24% by weight are alumina from boehmite and 16% by weight are alumina from alumina sol).

[0179] The catalyst A-5 described above was prepared using a method comprising the following steps:

[0180] 1.8 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 0.45 kg of halloysite (dry basis, provided by Lanzhou Petrochemical Company Catalyst Plant, the same below), 8.462 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 13.333 kg of deionized water were added to a slurry tank and slurried. Then 8.16 kg of pseudoboehmite (solid content 62.5 wt%, product of Shanxi Aluminum Plant, the same below) was added and stirred for 2 hours. Then 363 mL of concentrated hydrochloric acid was added and stirred for 1.2 hours. After that, the mixture was aged at 60°C for 1.4 hours.

[0181] 1.5 kg of NH4Y molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 11.73, the same below), 2.25 kg of the above-mentioned phosphorus and zinc modified MCM-68 molecular sieve, 2.25 kg of ZSM-23 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 60, the same below) and 8 kg of deionized water were mixed and pulped for 2 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1.2 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 550℃ and the temperature of the spray exhaust gas was controlled at 300℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 650℃ for 1.5 hours, washed at 80℃ and dried at 150℃ to obtain catalyst A-5.

[0182] Based on the mass of catalyst A-5 as 100%, it comprises: 10% by weight of Y-type molecular sieve on a dry basis, 15% by weight of phosphorus and zinc modified MCM-68 molecular sieve on a dry basis, 15% by weight of MTT structured molecular sieve on a dry basis, 15% by weight of clay on a dry basis, and 45% by weight of binder on an oxide basis (of which 34% by weight is alumina from boehmite and 11% by weight is alumina from alumina sol).

[0183] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 0%, 1.10%, and 1.93%, respectively.

[0184] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer, and the carbon content of the mixed semi-regenerated catalyst obtained above was 0.12%.

[0185] Comparative Example 1

[0186] This comparative example provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene, similar to Example 2, except that the apparatus used is different. This comparative example uses... Figure 2 The device shown is similar to... Figure 1 compared to, Figure 2 There are no inlets, outlets, or pipelines related to catalyst B-1. The specifications of the riser reactor and fluidized bed reactor are the same as in Example 2, and the reaction pressure (sedimentation pressure) is also the same. The method provided in this comparative example specifically includes the following steps:

[0187] Aged catalyst A-1 was used as the catalyst. After normal operation, fully regenerated mixed catalyst 1 was used to replace catalyst A-1. The specific steps included:

[0188] Catalyst A-1, after hydrothermal deactivation treatment, is added to regenerator 7 through catalyst A inlet 17. After regenerator 7 is heated to the required conditions for atomizing steam, stripping steam, and feedstock oil, catalyst A-1 is transported to the pre-lifting section through catalyst delivery pipeline 19 and slide valve 20. Then, under the lifting action of nitrogen gas added through pre-lifting medium inlet 13, it moves upward in the pre-lifting section of riser reactor 1 and reacts with diesel fuel (added through diesel inlet 12) preheated at 200℃ and atomized by atomizing steam in the first reaction zone to obtain the first oil-agent mixture. The contact reaction temperature is 745℃, the time is 0.7s, the weight ratio of catalyst A-1 to diesel fuel (agent-to-oil ratio) is 40:1, the weight ratio of atomizing steam to diesel fuel is 0.1, and the outlet temperature of the first reaction zone is 730℃.

[0189] The first oil-agent mixture obtained from the reaction in the first reaction zone of the riser reactor 1 rises to the second reaction zone of the expansion section for further reaction; the second oil-agent mixture obtained after the reaction enters the first separator 4, where it is separated to obtain the first oil-gas and the first carbon deposit catalyst A-1. The first oil-gas enters the fractionation-absorption-stabilization unit 23 through the oil-gas outlet pipeline 16, where it is separated to obtain methane 24, ethane 25, ethylene 26, propane 27, propylene 28, and C4~C6 compounds. 12 Non-aromatic components 29, heavy gasoline 30, cracked diesel 31, and slurry oil 32. The first carbonized catalyst A-1 enters the settling tank 3 for settling and then enters the stripper 5. After steam stripping, the resulting spent catalyst enters the regenerator 7 via the spent catalyst delivery pipeline 6 for complete catalyst regeneration, yielding a fully regenerated catalyst. The complete regeneration temperature is 770℃, the regeneration medium enters from the air inlet 40, and the regeneration air flow rate is 30 L / min. The regenerated flue gas is discharged from the flue gas outlet 8. The flue gas is analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 are 5.1%, 0.5%, and 6.02%, respectively.

[0190] Catalyst A-1, after hydrothermal deactivation treatment in regenerator 7, moves upward in the pre-lifting section of fluidized bed reactor 2 via catalyst delivery pipeline 21 and slide valve 22, under the lifting action of pre-lifting medium (added through pre-lifting medium inlet 14), and interacts with preheated, atomized C4~C4. 12 Non-aromatic components (obtained through fractionation-absorption-stabilization unit 23 and entering the fluidized bed reactor through non-aromatic component inlet 15) react in fluidized bed reactor 2 at a contact temperature of 745℃. The C4-C4 components in fluidized bed reactor 2... 12 The weight ratio of non-aromatic hydrocarbon components to diesel fuel in riser reactor 1 is 0.12. Catalyst A-1 and C4~C2 enter fluidized bed reactor 2. 12The weight ratio of non-aromatic components (co-oil ratio) is 40:1, and the atomized steam contains C4-C4 hydrocarbons. 12 The non-aromatic hydrocarbon component has a weight ratio of 0.1, and the residence time of catalyst A-1 and oil / gas in the fluidized bed reactor is 1.5 s. After the reaction, the mixture of the second oil / gas and the carbonized catalyst A-1 flows into the second separator 41 through the fluidized bed reactor outlet pipeline 9 for separation. The separated second carbonized catalyst A-1 enters the middle of the second reaction zone in the riser reactor 1 through the carbonized catalyst conveying pipeline 10 and the slide valve 11, where it reacts with the first oil / gas mixture in the second reaction zone. The residence time of the second carbonized catalyst A-1 and the first oil / gas mixture in the second reaction zone is 1.5 s, and the outlet temperature of the second reaction zone is 710℃. The second oil / gas mixes with the subsequent first oil / gas through the oil / gas outlet pipeline 16 and enters the fractionation-absorption-stabilization unit 23 for separation.

[0191] The weight ratio of the second carbon deposit catalyst A-1 in the second reaction zone of the expansion section of the riser reactor 1 after reaction in the fluidized bed reactor 2 to the first oil mixture in the second reaction zone of the riser reactor 2 is 0.11.

[0192] The fully regenerated catalyst obtained from complete regeneration in the regenerator is recycled into the first reaction zone of the riser reactor and the fluidized bed reactor to replace catalyst A-1; thus, the various devices and pipelines cooperate to form a stable reaction system. In this comparative example, only one catalyst, A-1 (the same catalyst A-1 in Example 2), was used. Specific reaction results are shown in Table 5.

[0193] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer. The carbon content of the fully regenerated catalyst obtained in this comparative example was 0.01%.

[0194] Comparative Example 2

[0195] This comparative example provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene, similar to Example 3, except that the apparatus used is different. This comparative example uses... Figure 2 The device shown is similar to... Figure 1 compared to, Figure 2 There are no inlets, outlets, or pipelines related to catalyst B-2 in this comparative example. The specifications of the riser reactor and fluidized bed reactor are the same as in Example 3, and the reaction pressure (sedimentation pressure) is also the same. The process related to catalyst B-2 is omitted in this comparative example. Only one catalyst, A-2 (the same catalyst A-2 in Example 3), is used in the entire process. The fully regenerated catalyst obtained by complete regeneration in the regenerator is recycled into the first reaction zone of the riser reactor and the fluidized bed reactor to replace catalyst A-2.

[0196] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 5.7%, 0.4%, and 4.26%, respectively. The carbon content of the catalyst was determined using an HIR-944B infrared carbon analyzer. The carbon content of the fully regenerated catalyst obtained in this comparative example was 0.01%. Specific reaction conditions and results are shown in Table 5.

[0197] Comparative Example 3

[0198] This comparative example provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene, similar to Example 4, except that the apparatus used is different. This comparative example uses... Figure 2 The device shown is similar to... Figure 1 compared to, Figure 2 There are no inlets, outlets, or pipelines related to catalyst B-3 in this comparative example. The specifications of the riser reactor and fluidized bed reactor are the same as in Example 4, and the reaction pressure (sedimentation pressure) is also the same. The process related to catalyst B-3 is omitted in this comparative example. Only one catalyst, A-3 (the same catalyst A-3 in Example 4), is used in the entire process. The fully regenerated catalyst obtained by complete regeneration in the regenerator is recycled into the first reaction zone of the riser reactor and the fluidized bed reactor to replace catalyst A-3.

[0199] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 6.1%, 0.4%, and 2.99%, respectively.

[0200] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer. The carbon content of the fully regenerated catalyst obtained in this comparative example was 0.01%. Specific reaction conditions and results are shown in Table 5.

[0201] Comparative Example 4

[0202] This comparative example provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene, similar to Example 5, except that the apparatus used is different. This comparative example uses... Figure 2 The device shown is similar to... Figure 1 compared to, Figure 2 There are no inlets, outlets, or pipelines related to catalyst B-4 in this comparative example. The specifications of the riser reactor and fluidized bed reactor are the same as in Example 5, and the reaction pressure (sedimentation pressure) is also the same. The process related to catalyst B-4 is omitted in this comparative example. Only one catalyst, A-4 (the same catalyst A-4 in Example 5), is used in the entire process. The fully regenerated catalyst obtained by complete regeneration in the regenerator is recycled into the first reaction zone of the riser reactor and the fluidized bed reactor to replace catalyst A-4.

[0203] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 5.9%, 0.4%, and 3.69%, respectively.

[0204] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer. The carbon content of the fully regenerated catalyst obtained in this comparative example was 0.01%. Specific reaction conditions and results are shown in Table 5.

[0205] Comparative Example 5

[0206] This comparative example provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene, similar to Example 6, except that the apparatus used is different. This comparative example uses... Figure 2 The device shown is similar to... Figure 1 compared to, Figure 2 There are no inlets, outlets, or pipelines related to catalyst B-5 in this comparative example. The specifications of the riser reactor and fluidized bed reactor are the same as in Example 6, and the reaction pressure (sedimentation pressure) is also the same. The process related to catalyst B-5 is omitted in this comparative example. Only one catalyst, A-5 (the same catalyst A-5 in Example 5), is used in the entire process. The fully regenerated catalyst obtained by complete regeneration in the regenerator is recycled into the first reaction zone of the riser reactor and the fluidized bed reactor to replace catalyst A-5.

[0207] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 6.0%, 0.4%, and 3.35%, respectively.

[0208] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer. The carbon content of the fully regenerated catalyst obtained in this comparative example was 0.01%. Specific reaction conditions and results are shown in Table 5.

[0209] Comparative Example 6

[0210] This comparative example provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene, similar to Example 5. The specifications of the riser reactor and fluidized bed reactor are the same as in Example 5, and the reaction pressure (sedimentation pressure) is also the same. The difference is that different catalysts are used. Catalysts C-1 and D-1 are used instead of catalysts A-4 and B-4, respectively. The incompletely regenerated catalyst (mixed semi-regenerated catalyst) obtained by incomplete regeneration in the regenerator is recycled into the first reaction zone of the riser reactor and the fluidized bed reactor to replace catalyst C-1.

[0211] In this comparative example, aged catalysts C-1 and D-1 were used. After normal operation, a mixed semi-regenerated catalyst was used to replace catalyst C-1. The preparation of catalysts C-1 and D-1 specifically includes the following steps:

[0212] The preparation steps of phosphorus and iron modified ZSM-5 molecular sieves are as follows:

[0213] First, 1072.13g of phosphoric acid was dissolved in 7.5kg of deionized water. Then, 7.5kg of ZSM-5 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 50, the same below) and the deionized phosphoric acid aqueous solution were placed in a slurry tank and stirred and impregnated at room temperature for 2h. After that, it was dried in an oven at 140℃ for 7h, and then calcined in a muffle furnace at 600℃ for 2h to obtain P2O5 modified ZSM-5 molecular sieve.

[0214] 384.75 g of ferric nitrate nonahydrate was dissolved in deionized water. Then, 7.65 kg of P2O5-modified ZSM-5 molecular sieve was mixed evenly with ferric nitrate nonahydrate and placed in a pulping tank. The mixture was stirred and impregnated at room temperature for 2 h, dried in an oven at 140 °C for 7 h, and then calcined in a muffle furnace at 600 °C for 2 h to obtain ZSM-5 molecular sieve modified with 5% P2O5 and 1% iron oxide.

[0215] The catalyst D-1 described above was prepared using a method comprising the following steps:

[0216] 4.56 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 0.24 kg of sepiolite (dry basis, industrial product of Hubei Shixing Chemical Co., Ltd., the same below), 3.077 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 19 kg of deionized water were added to a pulping tank and pulped. Then 5.28 kg of pseudoboehmite (solid content 62.5 wt%, product of Shanxi Aluminum Plant, the same below) was added and stirred for 2 hours. Then 500 mL of concentrated hydrochloric acid was added and stirred for 1.2 hours. After that, the mixture was aged at 60°C for 1.4 hours.

[0217] 6.3 kg of the above-mentioned phosphorus and iron modified ZSM-5 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-aluminum ratio 50, the same below) and 8.333 kg of deionized water were mixed and pulped for 2 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1.2 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 525℃ and the temperature of the spray exhaust gas was controlled at 275℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 600℃ for 2 hours, washed at 70℃ and dried at 140℃ to obtain catalyst D-1.

[0218] Based on the mass of catalyst D-1 (100%), it comprises: 42 wt% phosphorus and iron modified ZSM-5 molecular sieve on a dry basis, 32 wt% clay on a dry basis, and 26 wt% binder on an oxide basis (of which 22 wt% is alumina from boehmite and 4 wt% is alumina from alumina sol).

[0219] The catalyst C-1 mentioned above was prepared by a method including the following steps:

[0220] 4.28 kg of kaolin (dry basis, industrial product of China Kaolin Company, the same below), 0.22 kg of sepiolite (dry basis, industrial product of Hubei Shixing Chemical Co., Ltd., the same below), 4.615 kg of alumina sol (containing 19.5 wt% Al2O3, produced by Lanzhou Petrochemical Company Catalyst Plant, the same below) and 19 kg of deionized water were added to a pulping tank and pulped. Then 5.28 kg of pseudoboehmite (solid content 62.5 wt%, product of Shanxi Aluminum Plant, the same below) was added and stirred for 1.2 hours. Then 500 mL of concentrated hydrochloric acid was added and stirred for 1.4 hours. After that, the mixture was aged at 50°C for 1.6 hours.

[0221] 1.05 kg of HY molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 11.25, the same below), 5.25 kg of the above-mentioned phosphorus and iron modified ZSM-5 molecular sieve (dry basis, product of Tianjin Nanhua Catalyst Co., Ltd., silicon-to-aluminum ratio 50, the same below) and 8.333 kg of deionized water were mixed and pulped for 1.2 hours, and then added to the above-mentioned pulping tank. The pulping was homogenized for 1.4 hours. The spray drying conditions were controlled as follows: the temperature of the spray tower furnace was controlled at 525℃ and the temperature of the spray exhaust gas was controlled at 275℃ to obtain catalyst microspheres. The catalyst microspheres obtained by spray drying were calcined at 600℃ for 2 hours, washed at 70℃ and dried at 140℃ to obtain catalyst C-1.

[0222] Based on the mass of catalyst C-1 as 100%, it comprises: 7% by weight of Y-type molecular sieve on a dry basis, 35% by weight of phosphorus and iron modified ZSM-5 molecular sieve on a dry basis, 30% by weight of clay on a dry basis, and 28% by weight of binder on an oxide basis (of which 22% by weight is alumina from boehmite and 6% by weight is alumina from alumina sol).

[0223] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 0%, 1.32%, and 2.9%, respectively.

[0224] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer, and the carbon content of the mixed semi-regenerated catalyst obtained above was 0.23%.

[0225] Comparative Example 7

[0226] This comparative example provides a method for the catalytic conversion of diesel fuel to produce ethylene and propylene, which is similar to Example 5. The specifications of the riser reactor, fluidized bed reactor, and catalyst are the same as in Example 5, and the reaction pressure (sedimentation pressure) is also the same. The difference is that the catalyst is completely regenerated, and the regeneration air flow rate is 30 L / min.

[0227] The flue gas was analyzed using an oxygen analyzer, a CO analyzer, and a CO2 analyzer. The concentrations of O2, CO, and CO2 were 6%, 0.4%, and 4.26%, respectively.

[0228] The carbon content of the catalyst was determined by an HIR-944B infrared carbon analyzer. The carbon content of the fully regenerated catalyst obtained in this comparative example was 0.01%. Specific reaction conditions and results are shown in Table 5.

[0229] Table 4 Results of the Examples

[0230]

[0231]

[0232] Table 5 Comparative results

[0233] project Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 The outlet temperature of reaction zone II, ℃ 710 670 630 650 640 650 650 Regenerated air flow rate, L / min 30 30 30 30 30 25 30 Material balance, wt% dry air 43.53 38.27 33.66 35.92 34.87 38.37 42.92 Liquefied gas 36.09 39.87 43.67 41.94 42.77 42.54 41.24 gasoline 11.24 14.22 15.62 14.75 15.12 12.45 8.15 pyrolysis diesel 2.83 2.95 3.12 3.03 3.07 2.75 2.65 Oil slurry 1.03 0.84 0.71 0.78 0.75 0.81 0.96 coke 5.28 3.85 3.22 3.58 3.42 3.08 4.08 hydrogen 0.83 0.67 0.61 0.63 0.62 0.52 0.55 methane 8.35 5.94 4.39 5.34 4.91 4.65 5.39 ethylene 29.24 25.07 20.32 22.69 21.73 25.84 26.21 propylene 23.79 26.35 28.95 27.83 28.45 29.65 29.02 Ethylene + Propylene 53.03 51.42 49.27 50.52 50.18 55.49 55.23

[0234] As shown in Tables 4 and 5, compared with the comparative examples, the method provided by this invention can achieve a higher ethylene + propylene yield and lower methane and coke yields. Specifically, compared with Comparative Example 1, under the condition of equal riser outlet temperature (i.e., outlet temperature of reaction zone II) in Example 2, the ethylene yield is 6.29 percentage points higher, the propylene yield is 1.92 percentage points higher, the ethylene + propylene yield is 8.21 percentage points higher, and the methane and coke yields are 1.26 and 1.78 percentage points lower, respectively; compared with Comparative Example 2, under the condition of equal riser outlet temperature (i.e., outlet temperature of reaction zone II) in Example 3, the ethylene yield is 6.01 percentage points higher, the propylene yield is 2.66 percentage points higher, the ethylene + propylene yield is 8.67 percentage points higher, and the methane and coke yields are 1.31 and 1.53 percentage points lower, respectively; compared with Comparative Example 3, under the condition of equal riser outlet temperature (i.e., outlet temperature of reaction zone II) in Example 4, the ethylene yield is 4.86 percentage points higher. In Example 5, under the same riser outlet temperature (i.e., the outlet temperature of reaction zone II), the ethylene yield was 4.59 percentage points higher, the ethylene + propylene yield was 9.45 percentage points higher, and the methane and coke yields were 1.25 and 1.07 percentage points lower, respectively. Compared with Comparative Example 4, in Example 5, under the same riser outlet temperature (i.e., the outlet temperature of reaction zone II), the ethylene yield was 6.06 percentage points higher, the propylene yield was 3.29 percentage points higher, the ethylene + propylene yield was 9.35 percentage points higher, and the methane and coke yields were 1.38 and 1.20 percentage points lower, respectively. Compared with Comparative Example 5, in Example 6, under the same riser outlet temperature (i.e., the outlet temperature of reaction zone II), the ethylene yield was 5.32 percentage points higher, the propylene yield was 3.82 percentage points higher, the ethylene + propylene yield was 9.14 percentage points higher, and the methane and coke yields were 1.69 and 1.21 percentage points lower, respectively. Compared to Comparative Example 6, under the same riser outlet temperature (i.e., the outlet temperature of reaction zone II) in Example 5, the ethylene yield was 2.91 percentage points higher, the propylene yield was 1.47 percentage points higher, the ethylene + propylene yield was 4.38 percentage points higher, and the methane and coke yields were 0.69 and 0.7 percentage points lower, respectively. Compared to Comparative Example 7, under the same riser outlet temperature (i.e., the outlet temperature of reaction zone II) in Example 5, the ethylene yield was 2.54 percentage points higher, the propylene yield was 2.10 percentage points higher, the ethylene + propylene yield was 4.64 percentage points higher, and the methane and coke yields were 1.43 and 1.7 percentage points lower, respectively.

[0235] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for the catalytic conversion of diesel fuel to produce ethylene and propylene, characterized in that, Includes the following steps: S1: Diesel fuel reacts with catalyst A in the first reaction zone of the riser reactor, and the resulting first oil-catalyst mixture enters the second reaction zone of the riser reactor to react with catalyst B. The resulting second oil-catalyst mixture is separated to obtain first oil-gas and mixed carbon deposit catalyst; the first oil-gas is separated, and the mixed carbon deposit catalyst enters the settling tank. S2: C4~C obtained after the first oil-gas separation 12 Non-aromatic components react with catalyst A in a fluidized bed reactor to obtain a third oil-agent mixture. After separation, a second oil-gas and carbon-depositing catalyst A are obtained. The carbon-depositing catalyst A enters the second reaction zone to react with catalyst B and the first oil-agent mixture. The second oil-gas is mixed with the first oil-gas and then separated. S3: The mixed carbon deposition catalyst and the carbon deposition catalyst A in the settling tank are stripped and then enter the regenerator for semi-regeneration. The resulting mixed semi-regenerated catalyst is recycled into the first reaction zone and the fluidized bed reactor to replace the catalyst A. The catalyst B includes a modified MSE molecular sieve and an MTT molecular sieve. The catalyst A includes Y-type molecular sieves, molecular sieves with modified MSE structure, and molecular sieves with MTT structure; Based on the mass of the mixed semi-regenerated catalyst as 100%, the carbon content therein is 0.05%-0.3%.

2. The method as described in claim 1, characterized in that, Within the first reaction zone, the weight ratio of catalyst A to diesel oil is 15:1 to 40:

1.

3. The method as described in claim 1 or 2, characterized in that, The temperature at which catalyst A reacts with diesel fuel in the first reaction zone is 655~745℃, and the reaction time is 0.7~2.0s.

4. The method as described in claim 1, characterized in that, The outlet reaction temperature of the first reaction zone is 638~730℃; and / or The diesel fuel enters the first reaction zone at a temperature of 150~250℃.

5. The method as described in claim 1, characterized in that, The mass ratio of catalyst B to catalyst A entering the first reaction zone of the riser is 0.08 to 0.44; and / or The weight ratio of the coking catalyst A entering the second reaction zone from the fluidized bed reactor to the coking catalyst A in the first oil mixture is 0.1~0.4; and / or The mass ratio of catalyst B to the carbon deposition catalyst A entering the second reaction zone from the fluidized bed reactor is 0.8 to 1.

13.

6. The method as described in claim 1, characterized in that, The residence time of the catalyst B and the first oil mixture is 1.5~3.2s.

7. The method as described in claim 1, characterized in that, The outlet temperature of the second reaction zone is 620~715℃.

8. The method as described in claim 1, characterized in that, The catalyst B enters the second reaction zone at a temperature of 643~730°C; preferably, the catalyst B enters the second reaction zone after heat exchange in the regenerator to 643~730°C; more preferably, the temperature of the regenerator is 700~770°C.

9. The method as described in claim 1, characterized in that, Within the fluidized bed reactor, catalyst A and C4~C 12 The non-aromatic components have a weight ratio of 15:1 to 40:1 and a residence time of 1.5 to 4.2 s; and / or Within the fluidized bed reactor, catalyst A and C4~C 12 The contact temperature for non-aromatic components is 655~745℃.

10. The method as described in claim 1, characterized in that, The C4~C in the fluidized bed reactor 12 The weight ratio of the non-aromatic component to the diesel fuel in the first reaction zone is 0.12 to 0.

40.

11. The method as described in claim 1, characterized in that, Based on the mass of catalyst B (100%), it comprises 1% to 38% (dry basis) of a modified MSE structure molecular sieve, 5% to 40% (dry basis) of a MTT structure molecular sieve, 10% to 40% (dry basis) of clay, and 19% to 50% (dry basis) of a binder based on oxides.

12. The method as described in claim 1, characterized in that, Based on the mass of catalyst A (100%), it comprises 1% to 15% (dry basis) of Y-type molecular sieve, 1% to 30% (dry basis) of molecular sieve with modified MSE structure, 5% to 25% (dry basis) of molecular sieve with MTT structure, 15% to 50% (dry basis) of clay, and 10% to 45% (dry basis) of binder.

13. The method as described in claim 11 or 12, characterized in that, The modified MSE structure is a molecular sieve modified with phosphorus and transition metals, specifically MCM-68 molecular sieve. Preferably, based on the mass of the modified MSE structure molecular sieve (100%), the phosphorus content is 0.5% to 5% and the transition metal content is 0.5% to 5% in terms of oxides.

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