A process for the production of a gasoline blending component, the resulting gasoline blending component and a reaction apparatus

Abstract

A method for producing gasoline blending components, the obtained gasoline blending components and a reaction device, light hydrocarbon raw materials enter a catalytic distillation column, so that 5-20% of benzene and naphthenes in the light hydrocarbon raw materials enter the light hydrocarbon isomerization reaction section to undergo isomerization reaction, and then are separated through a rectification section, C5 alkanes and multi-methyl C6 isomeric alkanes are obtained at the top; the side line discharge enters an aromatization reaction zone to undergo aromatization reaction, and the reaction product of the aromatization reaction zone is used as a circulating material; 80-95% of benzene and naphthenes in the light hydrocarbon raw materials and other heavy components enter a naphthenic isomerization reaction zone to undergo benzene saturation and naphthenes isomerization reaction, and then the liquid phase product obtained after gas-liquid separation of the reaction stream is mixed with the top discharge of the catalytic distillation column to obtain high-octane gasoline blending components. The method provided by the application reduces the benzene content of the obtained gasoline blending components, increases the yield of naphthenes, and the octane number of the gasoline blending components is high.

Description

Technical Field

[0001] This invention relates to a technology for producing gasoline blending components with high cycloalkanes, specifically a technology for producing high-octane gasoline blending components using C5-C8 light alkanes as raw materials, reducing the benzene content and increasing the production of cycloalkanes. Background Technology

[0002] With increasing environmental awareness and continuous improvement of environmental regulations, standards for automotive gasoline are becoming increasingly stringent. In recent years, my country has been accelerating the upgrading of automotive gasoline quality standards. The China VI A standard for automotive gasoline, which came into effect nationwide on January 1, 2019, imposes higher requirements on gasoline quality than the existing China V standard. Aromatic hydrocarbon content is reduced to 35% by volume, benzene content to 0.8% by volume, and olefin content to 18% by volume. It also imposes stricter regulations on metals and other harmful substances. The China VI B standard for automotive gasoline, expected to come into effect on January 1, 2023, will further reduce olefin content to 15% by volume.

[0003] Currently, the main sources of gasoline blending components in my country are catalytic gasoline and reformed gasoline, with the remainder being alkylated gasoline and MTBE, etc. Catalytic gasoline is the most important gasoline blending component in my country, but it has high sulfur and olefin content and a low octane number. Reformed gasoline, on the other hand, has a high octane number and very low olefin, sulfur, and nitrogen content, but it has a high content of aromatics and benzene, contributing approximately 75-80% of the total benzene content in the gasoline blend. Although my country's reforming scale is currently smaller than catalytic cracking compared to the global scale, with the continuous upgrading of gasoline quality and the expansion of reforming scale, the proportion of reformed gasoline will inevitably continue to increase. Therefore, how to reduce the aromatics and benzene content in reformed gasoline to meet gasoline quality requirements has become a problem we must address.

[0004] There are different ways to deal with the benzene content in reformed products. For example, pre-fractionation and pretreatment of benzene precursors in reforming feedstocks can reduce the benzene content in the product. However, this method cannot remove the benzene generated during the reforming process and will result in a loss of octane number. Another method is to reduce benzene content by hydrogenation saturation. For example, USP7175754A discloses a method to reduce benzene content in gasoline products by hydrogenating benzene to cyclohexane. This method has a significant effect on reducing benzene content, but it results in a large loss of octane number, high hydrogen consumption, and a complex process. The low-octane gasoline after treatment still needs further processing before it can be blended into the gasoline pool.

[0005] Light hydrocarbon isomerization technology can convert low-octane straight-chain alkanes in feedstocks into higher-octane isoalkanes, producing products with very low sulfur content and free of aromatics, olefins, and benzene. These products are not only high-quality gasoline blending components but also align with the current trend towards cleaner energy, making them an effective means of gasoline quality improvement. The combination of catalytic reforming and isomerization processes, which separates and isomerizes the C5 and C6 fractions from the reforming product and then directly adds them to the gasoline fraction to increase the octane number, is a well-known combined process described in documents such as USP4457832A, USP4181599A, and USP3761392A.

[0006] EP552070A discloses a process for reducing benzene in gasoline fractions. The raw material used in this process consists of 40-80% alkanes, 0.5-7.0% cycloalkanes and 6-45% aromatics, with a maximum distillation temperature of 70-90°C. After hydrogenation, the raw material is mixed with the raw material or C5 or C6 fractions and then subjected to an isomerization reaction.

[0007] USP5948948A discloses a process for isomerization of alkanes using catalytic distillation. The process uses C5 and C6 alkanes as feedstocks. The catalytic distillation column contains at least one reaction zone and one rectification zone. The column is in a hydrogen-rich state, with a total pressure of 0.4–1 MPa and a reaction zone temperature of 100–160 °C. The catalyst used is an isomerization catalyst containing group VIII metals supported on alumina or zeolite. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a method for producing gasoline blending components from benzene-rich light alkanes. This method can utilize benzene and cycloalkanes in the raw materials to control the depth of isomerization reaction, reduce the saturated vapor pressure of the product, reduce the benzene content in the product, and increase the production of cycloalkanes to obtain gasoline blending components with high octane number.

[0009] A method for producing gasoline blending components includes a catalytic distillation column comprising, from top to bottom: a rectification section, a light hydrocarbon isomerization reaction section, and a stripping section. Light hydrocarbon feedstock enters the catalytic distillation column, where 5-20% by mass of benzene and cycloalkanes undergo isomerization in the light hydrocarbon isomerization reaction section. After separation in the rectification section, C5 alkanes and polymethyl C6 isoalkanes are obtained at the top of the column. A side stream from the rectification section is drawn into the aromatization reaction zone for aromatization. The reaction products from the aromatization reaction zone are returned to the catalytic distillation column as recycled material. Finally, 80-95% by mass of benzene and cycloalkanes from the light hydrocarbon feedstock, along with other heavy components, pass through the stripping section and enter the cycloalkanes isomerization reaction zone for benzene saturation and cycloalkanes isomerization. The resulting liquid product, obtained after gas-liquid separation, is mixed with the top product from the catalytic distillation column to obtain a high-octane gasoline blending component.

[0010] The present invention provides a gasoline blending component obtained by the above-described method for producing gasoline blending components.

[0011] A reaction apparatus for producing gasoline blending components includes a catalytic distillation tower comprising, from top to bottom, at least a rectification section, a light hydrocarbon isomerization reaction section, and a stripping section; the catalytic distillation tower is connected to the inlet of the aromatization reaction zone via a side feed line, and the outlet of the aromatization reaction zone is connected to the catalytic distillation tower via a circulating material pipeline; the bottom of the catalytic distillation tower is connected to the inlet of the cycloalkane isomerization reaction zone; and the outlet of the cycloalkane isomerization reaction zone is connected to a gas-liquid separator.

[0012] The beneficial effects of the method and reaction apparatus for producing gasoline blending components provided by the present invention are as follows:

[0013] The method for producing gasoline blending components provided by this invention organically combines the light hydrocarbon isomerization process, alkane aromatization process, aromatic saturation isomerization process and product separation through a catalytic distillation process. This method not only produces abundant multi-branched isoalkanes, but also converts benzene into C6 cycloalkanes rich in methylcyclopentane, resulting in gasoline blending components that are essentially free of benzene, and effectively compensates for the loss of octane number caused by benzene reduction.

[0014] The method provided by this invention reduces the benzene content of the gasoline blending component while increasing the production of cycloalkanes, resulting in a high octane number for the gasoline blending component.

[0015] The reaction apparatus for producing gasoline blending components provided by this invention is applicable to the above method. Attached Figure Description

[0016] Figure 1 This is a schematic flowchart of a first embodiment of the method for producing gasoline blending components according to the present invention.

[0017] Figure 2 This is a schematic flowchart of a second embodiment of the method for producing gas-oil blending components according to the present invention.

[0018] Figure 3 This is a schematic diagram of the process for producing gasoline blending components for Comparative Example 3.

[0019] Figure label:

[0020] 1-Raw material; 2-Catalytic distillation column; 3-Hydrocarbon isomerization reaction section

[0021] 6-Aromatization reaction zone; 8-Gas-liquid separator; 10-Cyclonal isomerization reaction zone

[0022] 12-Gas Stabilizer Tower; 4, 5, 7, 9, 11, 13, 14, 15-Pipelines Detailed Implementation

[0023] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0024] In a first aspect, the present invention provides a method for producing gasoline blending components. The catalytic distillation tower comprises, from top to bottom, at least a rectification section, a light hydrocarbon isomerization reaction section, and a stripping section. Light hydrocarbon feedstock enters the catalytic distillation tower, where 5-20% by mass of benzene and cycloalkanes from the feedstock undergo isomerization in the light hydrocarbon isomerization reaction section, followed by separation in the rectification section. C5 alkanes and polymethyl C6 isoalkanes are obtained at the top of the tower. A side stream is drawn from the rectification section and enters the aromatization reaction zone for aromatization. The reaction products from the aromatization reaction zone are returned to the catalytic distillation tower as recycled material. Then, 80-95% by mass of benzene and cycloalkanes from the light hydrocarbon feedstock, along with other heavy components, pass through the stripping section and enter the cycloalkanes isomerization reaction zone for benzene saturation and cycloalkanes isomerization. The resulting liquid product, obtained after gas-liquid separation, is mixed with the top product from the catalytic distillation tower to obtain a high-octane gasoline blending component.

[0025] In the method provided by the present invention, the light hydrocarbon raw material is C5-C8 alkanes, cycloalkanes and aromatics; preferably, the light hydrocarbon raw material composition is 20-80% by mass of C5-C8 alkanes, 0-50% by mass of cycloalkanes and 1-50% by mass of benzene.

[0026] In the method provided by this invention, the feed position of the catalytic distillation tower is located in the light hydrocarbon isomerization reaction section, and the return position of the recycled material from the aromatization reaction zone to the catalytic distillation tower is located below the light hydrocarbon isomerization reaction section, which can be in the stripping section or in the cycloalkane isomerization reaction zone.

[0027] In the method provided by this invention, the cycloalkane isomerization reaction zone is located outside the catalytic distillation column. Based on the total number of trays in the catalytic distillation column, the tray percentage of the rectification section is 25-50%, the tray percentage of the light hydrocarbon isomerization reaction section is 40-60%, and the tray percentage of the stripping section is 5-35%.

[0028] Preferably, the cycloalkane isomerization reaction zone is located inside the catalytic distillation column, which, from top to bottom, includes a rectification section, a light hydrocarbon isomerization reaction section, a first stripping section, a cycloalkane isomerization reaction zone, and a second stripping section.

[0029] When the cycloalkane isomerization reaction zone is located in the catalytic distillation column, based on the total number of trays in the catalytic distillation column, the tray ratio of the rectification section is 25-50%, the tray ratio of the light hydrocarbon isomerization reaction section is 35-65%, the tray ratio of the cycloalkane isomerization reaction zone is 10-35%, and the tray ratio of the first stripping section and the second stripping section is 0-30% each.

[0030] More preferably, the number of trays in the rectification section accounts for 30-40%, the number of trays in the light hydrocarbon isomerization reaction section accounts for 50-55%, and the number of trays in the cycloalkane isomerization reaction section accounts for 10-15%.

[0031] In the method provided by the present invention, the light hydrocarbon isomerization reaction section is filled with a solid superacid catalyst, wherein the solid superacid catalyst comprises a zirconium dioxide support containing sulfate and a noble metal supported thereon; preferably, based on the support, the sulfur content in the solid superacid catalyst is 0.5 to 5.0% by mass, and the noble metal content is 0.1 to 5.0% by mass, wherein the noble metal is selected from platinum or palladium.

[0032] In the method provided by the present invention, the cycloalkane isomerization reaction zone is filled with a zeolite-type catalyst, wherein the zeolite-type catalyst comprises 0.01 to 2.0% by mass of a noble metal and 97.5 to 99.9% by mass of a support, wherein the support comprises 10 to 90% by mass of zeolite and 10 to 90% by mass of alumina, wherein the noble metal is selected from platinum or palladium, and the zeolite is selected from mordenite, β-zeolite, or a mixture thereof.

[0033] In the method provided by this invention, the operating pressure of the catalytic distillation column is 0.2 MPa-5.0 MPa, preferably 0.5-5 MPa, more preferably 1.0-4.0 MPa; the top temperature is 60℃-150℃, more preferably 80℃-140℃; the bottom temperature is 200℃-300℃, more preferably 200-280℃; the side stream extraction temperature is 120℃-240℃, more preferably 140-200℃; and the feed mass hourly space velocity is 0.2-10.0 h⁻¹. -1 More preferably 0.5 to 5.0 h -1 The hydrogen / hydrocarbon molar ratio is 0.1 to 6.0, more preferably 0.5 to 5.0.

[0034] The light hydrocarbon isomerization reaction section is located inside the catalytic distillation tower, with a preferred temperature of 100–250°C, more preferably 160–190°C. The isomerization catalyst used in the isomerization reaction zone is a solid superacid isomerization catalyst, which is packed using a packing method.

[0035] The cycloalkane isomerization reactor can be located inside or outside the catalytic distillation column. It can be a fixed-bed reactor, a fluidized-bed reactor, or a moving-bed reactor. The catalyst used in the cycloalkane isomerization reactor is a zeolite-type isomerization catalyst.

[0036] When the cycloalkane isomerization reaction zone is separately located outside the catalytic distillation column, the reaction temperature of the cycloalkane isomerization reaction zone is 180–350°C, preferably 200–250°C, the reaction pressure is 0.1–5.0 MPa, preferably 0.2–3.0 MPa, and the feed mass hourly space velocity is 0.2–10.0 h⁻¹. -11 More preferably 0.5 to 5.0 h -1 The hydrogen / hydrocarbon molar ratio is 0.1 to 6, preferably 0.5 to 5.0.

[0037] The reactor in the aromatization reaction zone can be a fixed-bed reactor, a moving-bed reactor, or a fluidized-bed reactor. The aromatization reaction temperature is 380–550℃, preferably 400–500℃, the reaction pressure is 0.1–5.0 MPa, preferably 0.2–3.0 MPa, and the feed mass hourly space velocity is 0.2–10.0 h⁻¹. -1 Preferably, the time is 0.5 to 5.0 h. -1 The hydrogen / hydrocarbon molar ratio is 0.1 to 10, more preferably 0.5 to 8.0.

[0038] In the method provided by the present invention, the aromatization reaction zone is filled with an aromatization catalyst, which includes KL zeolite and Pt supported thereon in a content of 0.1 to 1.5% by mass based on KL zeolite; preferably, the aromatization catalyst also contains 0.5 to 2.0% by mass of halogen; the halogen is preferably fluorine and / or chlorine.

[0039] The method for producing gasoline blending components provided by this invention first feeds benzene-containing light hydrocarbon feedstock into a catalytic distillation tower. Under hydrogen-containing conditions, C5 and C6 straight-chain alkanes and monobranched alkanes in the feedstock undergo isomerization reactions in the light hydrocarbon isomerization reaction zone, transforming into multibranched alkanes. The di / multibranched C6 alkanes and C5 alkanes fractions are separated from the top of the tower as products. C6 n-alkanes, C6 monobranched isoalkanes, and some cyclohexane and benzene are drawn from the side stream of the catalytic distillation tower and enter the aromatization reaction zone. The liquid product in the aromatization reaction zone is returned to the catalytic distillation tower as recycled material. The benzene and cyclohexane-rich components at the bottom of the tower are fed into the cycloalkane isomerization reaction zone, where benzene saturation and cycloalkane isomerization reactions occur, partially transforming into methylcyclopentane. This is then mixed with the isomerized hydrocarbon components at the top of the tower and used as gasoline blending components. The method of this invention combines alkane isomerization, alkane aromatization and benzene saturation isomerization processes. The product is rich in high-octane components such as multi-branched isoalkanes, methylcyclopentane and cyclohexane, and does not contain benzene, making it an excellent clean gasoline blending component.

[0040] Secondly, the present invention provides a gasoline blending component obtained by the above-described method for producing gasoline blending components.

[0041] Thirdly, the present invention provides a reaction apparatus for producing gasoline blending components, wherein the catalytic distillation tower comprises at least a rectification section, a light hydrocarbon isomerization reaction section, and a stripping section from top to bottom; the catalytic distillation tower is connected to the inlet of the aromatization reaction zone via a side feed pipeline, and the outlet of the aromatization reaction zone is connected to the catalytic distillation tower via a circulating material pipeline; the bottom of the catalytic distillation tower is connected to the inlet of the cycloalkane isomerization reaction zone; and the outlet of the cycloalkane isomerization reaction zone is connected to a gas-liquid separator.

[0042] Preferably, the cycloalkane isomerization reaction zone is located inside the catalytic distillation column, which, from top to bottom, includes a rectification section, a light hydrocarbon isomerization reaction section, a first stripping section, a cycloalkane isomerization reaction zone, and a second stripping section.

[0043] In the reaction apparatus provided by the present invention, the light hydrocarbon isomerization reaction section is filled with a solid superacid catalyst, the cycloalkane isomerization reaction zone is filled with a zeolite-type catalyst, and the aromatization reaction zone is filled with an aromatization catalyst.

[0044] Preferably, the feed line of the catalytic distillation tower is located in the light hydrocarbon isomerization reaction section, and the circulating material line from the aromatization reaction zone is connected to the portion of the catalytic distillation tower located below the light hydrocarbon isomerization reaction section.

[0045] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0046] Figure 1 A schematic flow chart of a first embodiment of the method for producing gasoline blending components provided by the present invention is shown in the attached diagram. Figure 1As shown, the catalytic distillation column 2 comprises, from top to bottom, a rectification section, a light hydrocarbon isomerization reaction section 3, a first stripping section, a cycloalkane isomerization reaction zone 10, and a second stripping section. The cycloalkane isomerization reaction zone is located inside the catalytic distillation column. Benzene-containing light alkane feedstock enters the catalytic distillation column 2 via pipeline 1. The light components in the feedstock are separated within the column. 5%–20% by mass of the total cyclohexane and benzene in the feedstock undergo C5 / C6 isomerization reactions and benzene-saturated and cycloalkane isomerization reactions with the C5 / C6 alkanes entering the light hydrocarbon isomerization reaction section 3. After separation in the rectification section, hydrogen-rich bi / multi-branched C6 alkanes and C5 alkanes are separated at the top of the column and enter the gas-liquid separator 12 via pipeline 4. The hydrogen-rich gas obtained by separator 12 is fed into the catalytic distillation column as supplementary hydrogen via pipeline 13. C6 normal and C6 single-branched alkanes are extracted from the side stream. 5% to 20% of the total amount of chain isoalkanes, cyclohexane, and benzene enters the component and enters the aromatization reaction zone 6 via pipeline 5. The product from the aromatization reaction zone enters the gas-liquid separator 8 via pipeline 7. The liquid product separated by the gas-liquid separator 8 is mixed with light hydrocarbon feedstock via pipeline 9 and returned to the catalytic distillation tower as recycled material. The bottom of the catalytic distillation tower 2, rich in benzene and cyclohexane components, is sent to the cycloalkane isomerization reaction zone 10 to undergo benzene saturation and cycloalkane isomerization reactions. The reaction product is mixed with the isoalkanes from the top of the catalytic distillation tower 2 via pipeline 11 and enters the gasoline stabilization tower 12. The liquid product from the bottom of the stabilization tower is discharged from the unit as a gasoline blending component via pipeline 14.

[0047] Figure 2 A schematic flow chart of a second embodiment of the method for producing gas-liquid blended components provided by the present invention is attached. Figure 2 As shown, the catalytic distillation column 2 includes, from top to bottom: a rectification section, a light hydrocarbon isomerization reaction section 3, and a stripping section. The cycloalkane isomerization reaction zone 10 is located outside the catalytic distillation column 2, and the top inlet of the cycloalkane isomerization reaction zone is connected to the bottom of the catalytic distillation column via pipeline 15.

[0048] The method of this invention is applicable to processing benzene-rich light hydrocarbon feedstocks. It can remove benzene from the feedstock and produce more cycloalkanes during the light hydrocarbon isomerization reaction to obtain benzene-free high-octane gasoline blending components.

[0049] The present invention will be further described in detail below with examples, but the present invention is not limited thereto.

[0050] Catalyst Preparation Example 1

[0051] Zeolite-type isomerization catalysts were prepared according to the method in Example 1 of CN99105790.2.

[0052] (1) Preparation of composite carrier

[0053] Take 100 g of sodium-type mordenite with a silica / alumina molar ratio of 11.2 and 800 mL of 1 mol / L NH4Cl solution, exchange the solution at 90–95 °C for 3 h, filter, wash the obtained solid with deionized water, dry at 120 °C for 3 h, repeat the operation twice, then exchange the solution with 800 mL of 1 mol / L hydrochloric acid at 90–95 °C for 3 h, filter, wash with deionized water until the filtrate is neutral, calcine at 600 °C for 4 h to prepare hydrogen-type mordenite with a sodium content of 0.03% by mass and a silica / alumina molar ratio of 23.5.

[0054] Take 100 grams of sodium-type Beta zeolite with a silica / alumina molar ratio of 28.6 and prepare hydrogen-type Beta zeolite with a sodium content of 0.03% by mass using the ammonium exchange method described above.

[0055] The above-mentioned hydrogen-form mordenite, hydrogen-form Beta zeolite and SB aluminum hydroxide powder were mixed evenly in a dry basis mass ratio of 20:60:20. A nitric acid solution with a volume ratio of 1:1 was added and kneaded. The mass ratio of added nitric acid to solids was 1:16. The mixture was extruded into strips, dried at 120°C for 2 hours, and calcined at 550°C for 4 hours to obtain a composite zeolite carrier.

[0056] (2) Impregnation with platinum

[0057] The composite zeolite support obtained in step (1) was impregnated with a chloroplatinic acid solution prepared in a predetermined amount for 24 hours, dried at 120°C for 2 hours, and calcined at 550°C for 4 hours to obtain catalyst A with a platinum content of 0.35% by mass.

[0058] Catalyst Preparation Example 2

[0059] Solid superacid isomerization catalysts were prepared according to the method in Example 3 of CN03105390.4.

[0060] (1) Preparation of hydrated zirconium oxide

[0061] A 5% (w / w) aqueous solution of zirconium oxychloride (ZrOCl₂·8H₂O) was prepared. While stirring, 25% (w / w) ammonia solution was slowly added to adjust the pH to 10. The resulting zirconium hydroxide precipitate and solution were transferred together to an autoclave, sealed, and hydrothermally treated at 130°C for 24 hours. The resulting solid was washed with deionized water and filtered until all chloride ions were removed from the filtrate. The solution was dried at 110°C for 24 hours to obtain water and zirconium oxide powder.

[0062] (2) Preparation of a mixture of silicon dioxide and aluminum oxide

[0063] Take 25g of silicon solution (silicon oxide content of 40% by mass) and 54g of SB aluminum hydroxide powder, mix them evenly, dry at 110℃ for 24 hours, add 200ml of 10% NH4Cl solution, reflux at 80℃ for 3 hours with stirring, wash and filter with deionized water, repeat three times, and dry at 110℃ for 24 hours to obtain a mixture of silicon oxide and aluminum oxide.

[0064] (3) Preparation of solid superacid catalysts

[0065] Take 75g of hydrated zirconium oxide powder obtained in step (1) and add it to the mixture of silicon oxide and aluminum oxide obtained in step (2) and mix evenly. Add 150ml of 0.5mol / L sulfuric acid and impregnate for 1 hour. Dry at 110℃ for 24 hours. Add 4g of guar gum powder, 9ml of 40% by mass nitric acid and 130ml of deionized water. After thorough kneading, extrude into strips and dry at 110℃ for 24 hours. Calcine at 650℃ for 3 hours to obtain the carrier, wherein the mass ratio of zirconium oxide: silicon oxide: aluminum oxide is 60:8:32 and the sulfur content is 1.95% by mass (based on the total amount of zirconium oxide, silicon oxide and aluminum oxide).

[0066] The support obtained by the above method is impregnated with a chloroplatinic acid solution prepared in a predetermined amount for 4 hours, dried at 110°C for 24 hours, and calcined at 550°C for 3 hours to obtain catalyst B, wherein the platinum content calculated based on the support is 0.3% by mass (based on the total amount of zirconium oxide, silicon oxide and aluminum oxide).

[0067] Catalyst Preparation Example 3

[0068] Preparation of Pt / KL aromatization catalyst.

[0069] 100 g of KL zeolite (produced by Sinopec Catalyst Co., Ltd.) was impregnated with a supersaturated Pt(NH3)2Cl2 solution with a concentration of 15.7 mg / mL. The liquid / solid volume ratio during impregnation was 1.5:1. After impregnation, the solid was dried at 120 °C for 12 hours and calcined at 350 °C for 4 hours to prepare aromatization catalyst C with a Pt content of 1.0% by mass (based on KL zeolite).

[0070] Example 1

[0071] according to Figure 1 The process produces high-octane gasoline blending components with cycloalkanes. The catalytic distillation column has 60 trays, a feed temperature of 170℃, a top temperature of 160℃, a reflux ratio of 3, a bottom temperature of 240℃, and an operating pressure of 2.1MPa. The ratio of catalyst to inert packing is adjusted according to the reaction space velocity.

[0072] Using the mixed alkanes shown in Table 1 as feedstock, the mixture was fed into a catalytic distillation column via pipeline 1 located at the 25th tray. The cycloalkane isomerization reaction zone (located between the bottom and the 7th tray) was packed with zeolite-type isomerization catalyst A, the alkane isomerization reaction zone (located between the 8th and 38th trays) was packed with superacid isomerization catalyst B, and the aromatization reactor was packed with aromatization catalyst C. The alkane isomerization reaction conditions were 170℃, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and the amount of aromatics and cycloalkanes in the feedstock entering the alkane isomerization reaction zone accounting for 5% by mass of the total aromatics and cycloalkanes in the feedstock, with a feed mass hourly space velocity (HHSV) of 1.0 h⁻¹. -1 The side stream distillate located on tray 39, consisting mainly of C6 n-alkanes, monomethyl C6 alkanes, and cyclohexane, is sent to the aromatization reaction zone as feedstock. The aromatization reaction conditions are 430℃, 0.3 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 2.0 h⁻¹. -1 The liquid product after the aromatization reaction enters the cycloalkane isomerization reaction zone via the pipeline located on the fourth tray. The cycloalkane isomerization reaction conditions are 240℃, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 1.0 h⁻¹. -1 The components obtained from the cycloalkane isomerization reaction zone were mixed with the isomerized hydrocarbon components from the top of the tower and then sent to the stabilized gasoline tower. The reaction results are shown in Table 2.

[0073] Example 2

[0074] according to Figure 1 The process involves blending components from high-octane gasoline that produces cycloalkanes. The catalytic distillation column has 60 trays, a feed temperature of 170°C, a top temperature of 160°C, a reflux ratio of 3, a bottom temperature of 240°C, and an operating pressure of 2.1 MPa. The ratio of catalyst to inert packing is adjusted according to the reaction space velocity.

[0075] Using the mixed alkanes shown in Table 1 as feedstock, the mixture was fed into a catalytic distillation column via pipeline 1 located at the 25th tray. The cycloalkane isomerization reaction zone (located between the bottom and the 7th tray) was packed with zeolite-type isomerization catalyst A, the alkane isomerization reaction zone (located between the 8th and 38th trays) was packed with superacid isomerization catalyst B, and the aromatization reactor was packed with aromatization catalyst C. The alkane isomerization reaction conditions were 170℃, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and the amount of aromatics and cycloalkanes in the feedstock entering the alkane isomerization reaction zone accounting for 5% by mass of the total aromatics and cycloalkanes in the feedstock, with a feed mass hourly space velocity (HHSV) of 1.0 h⁻¹. -1 The side stream distillate located on tray 39, consisting mainly of C6 n-alkanes, monomethyl C6 alkanes, and cyclohexane, is sent to the aromatization reaction zone as feedstock. The aromatization reaction conditions are 480℃, 0.3 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 2.0 h⁻¹.-1 The liquid product following the aromatization reaction enters the cycloalkane isomerization reaction zone via a pipeline located on the fourth tray. The cycloalkane isomerization reaction conditions are 240℃, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 1.0 h⁻¹. -1 The components obtained from the cycloalkane isomerization reaction zone were mixed with the isomerized hydrocarbon components from the top of the tower and then sent to the stabilized gasoline tower. The reaction results are shown in Table 2.

[0076] Example 3

[0077] according to Figure 1 The process involves blending components from high-octane gasoline that produces cycloalkanes. The catalytic distillation column has 60 trays, a feed temperature of 170°C, a top temperature of 160°C, a reflux ratio of 3, a bottom temperature of 240°C, and an operating pressure of 2.1 MPa. The ratio of catalyst to inert packing is adjusted according to the reaction space velocity. Using the mixed alkanes shown in Table 1 as feedstock, it is introduced into the catalytic distillation column through pipeline 1 located at tray 25. The cycloalkanes isomerization reaction zone (located between the bottom and tray 5) is filled with zeolite-type isomerization catalyst A, the alkane isomerization reaction zone (located between tray 5 and tray 38) is filled with superacid isomerization catalyst B, and the aromatization reactor is filled with aromatization catalyst C. The alkane isomerization reaction conditions were 170℃, 2.1 MPa, hydrogen / hydrocarbon molar ratio of 3.0, and the amount of aromatics and cycloalkanes in the feed entering the alkane isomerization reaction zone accounted for 10% of the total aromatics and cycloalkanes in the feed, with a feed mass hourly space velocity of 1.0 h⁻¹. -1 The side stream distillate located on tray 39, consisting mainly of C6 n-alkanes, monomethyl C6 alkanes, and cyclohexane, is sent to the aromatization reaction zone as feedstock. The aromatization reaction conditions are 430℃, 0.3 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 2.0 h⁻¹. -1 The liquid product following the aromatization reaction enters the cycloalkane isomerization reaction zone via a pipeline located on the fourth tray. The cycloalkane isomerization reaction conditions are 240℃, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 1.0 h⁻¹. -1 The components obtained from the cycloalkane isomerization reaction zone were mixed with the isomerized hydrocarbon components from the top of the tower and then sent to the stabilized gasoline tower. The reaction results are shown in Table 2.

[0078] Example 4

[0079] according to Figure 1 The process involves blending components from high-octane gasoline that produces cycloalkanes. The catalytic distillation column has 60 trays, a feed temperature of 170°C, a top temperature of 160°C, a reflux ratio of 3, a bottom temperature of 240°C, and an operating pressure of 2.1 MPa. The ratio of catalyst to inert packing is adjusted according to the reaction space velocity.

[0080] Using the mixed alkanes shown in Table 1 as feedstock, the mixture was fed into a catalytic distillation column via pipeline 1. The cycloalkane isomerization reaction zone (located between the bottom and the 5th tray) was packed with zeolite-type isomerization catalyst A, the alkane isomerization reaction zone (located between the 5th and 38th trays) was packed with superacid isomerization catalyst B, and the aromatization reactor was packed with aromatization catalyst C. The alkane isomerization reaction conditions were 170℃, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and the amount of aromatics and cycloalkanes in the feedstock entering the alkane isomerization reaction zone accounting for 10% of the total aromatics and cycloalkanes in the feedstock, with a feed mass hourly space velocity (HHSV) of 1.0 h⁻¹. -1 The stream from the side stream located on tray 39, consisting mainly of C6 n-alkanes, monomethyl C6 alkanes, and cyclohexane, is sent to the aromatization reaction zone, while the stream from tray 25 is used as feedstock. The aromatization reaction conditions are 480℃, 0.3 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 2.0 h⁻¹. -1 The liquid product following the aromatization reaction enters the cycloalkane isomerization reaction zone via a pipeline located on the fourth tray. The cycloalkane isomerization reaction conditions are 240℃, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 1.0 h⁻¹. -1 The components obtained from the cycloalkane isomerization reaction zone were mixed with the isomerized hydrocarbon components from the top of the tower and then sent to the stabilized gasoline tower. The reaction results are shown in Table 2.

[0081] Comparative Example 1

[0082] The isomerization reaction was carried out using the zeolite catalyst prepared in Example 1. The mixed alkanes shown in Table 1 were used as feedstock and fed into an isomerization reactor packed with zeolite catalyst A. The reaction conditions were 240℃, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 1 h⁻¹. -1 The results of the liquid phase products obtained after gas-liquid separation of the isomerization products are shown in Table 2.

[0083] Comparing the data in Table 2, it can be seen that after the raw material is treated with a zeolite-type isomerization catalyst, all benzene is hydrogenated and converted, but the RON octane number of the product is low.

[0084] Comparative Example 2

[0085] The isomerization reaction was carried out using the solid superacid catalyst prepared in Example 2. The mixed alkanes shown in Table 1 were used as raw materials and fed into an isomerization reactor packed with solid superacid catalyst B. The reaction conditions were 170 °C, 2.1 MPa, a hydrogen / hydrocarbon molar ratio of 3.0, and a feed mass hourly space velocity (WHSV) of 1.0 h⁻¹. -1 The results of the liquid phase products obtained after gas-liquid separation of the isomerization products are shown in Table 2.

[0086] Comparing the data in Table 2, it can be seen that after the raw material is treated with a solid superacid catalyst, all benzene is hydrogenated and converted, but the MCP yield is low and the RON octane number of the product is low.

[0087] Comparative Example 3

[0088] Comparative Example 3 was blended from high-octane gasoline with high cycloalkane production; the process is shown in Appendix. Figure 3 The process differs from that of Example 1 in that it lacks an aromatization reaction zone. (See attached...) Figure 3 As shown, the catalytic distillation column consists of, from top to bottom, the first rectification section 16, the alkane isomerization reaction zone 3, the second rectification section 17, the stripping section 18, and the cycloalkane isomerization reaction zone 10.

[0089] The catalytic distillation column has 60 trays, a feed temperature of 170℃, a top temperature of 160℃, a reflux ratio of 3, a bottom temperature of 240℃, and an operating pressure of 2.1 MPa. The ratio of catalyst to inert packing is adjusted according to the reaction space velocity. Using the mixed alkanes shown in Table 1 as feed, the mixture is introduced into the catalytic distillation column through line 1 located at tray 25. The cycloalkane isomerization reaction zone (located between the bottom and tray 20) is packed with zeolite-type isomerization catalyst A, while the alkane isomerization reaction zone (located between trays 28 and 38) is packed with superacid isomerization catalyst B. The alkane isomerization reaction conditions are: 170℃, 2.1 MPa, hydrogen / hydrocarbon molar ratio of 3.0, the feed entering the alkane isomerization reaction zone does not contain aromatics or cycloalkanes, and the feed mass hourly space velocity (MHSV) is 1.0 h⁻¹. -1 The distillate stream from the tower, mainly composed of C6 n-alkanes and monomethyl C6 alkanes, is recycled to pipeline 1. The cycloalkane isomerization reaction conditions are 240℃, 2.1 MPa, hydrogen / hydrocarbon molar ratio of 3.0, and feed mass hourly space velocity (WHSV) of 1.0 h⁻¹. -1 The components obtained from the cycloalkane isomerization reaction zone were mixed with the isomerized hydrocarbon components from the top of the tower and then sent to the stabilized gasoline tower. The reaction results are shown in Table 2.

[0090] Comparing the data in Table 2, it can be seen that when there is no aromatization reaction zone and the raw materials in the alkane isomerization reaction zone do not contain aromatics or cycloalkanes, the saturated vapor pressure of the obtained product is higher.

[0091] Table 1

[0092] hydrocarbon components Content, mass % <![CDATA[i-C5]]> 23.2 <![CDATA[n-C5]]> 21.4 22DMB 4.2 23DMB 2.6 2MP 7.9 3MP 10 <![CDATA[n-C6]]> 18.3 MCP 1.1 B 10.1 CH 1.2 RON 69.6

[0093] The symbols in Table 1 have the following meanings (the same applies below): i-C5—isopentane, n-C5—n-pentane, 22DMB—2,2-dimethylbutane, 23DMB—2,3-dimethylbutane, 2MP—2-methylpentane, 3MP—3-methylpentane, n-C6—n-hexane, MCP—methylcyclopentane, B—benzene, CH—cyclohexane.

[0094] Table 2

[0095]

[0096]

Claims

1. A method for producing gasoline blending components, characterized in that, The catalytic distillation column comprises, from top to bottom, at least: a rectification section, a light hydrocarbon isomerization reaction section, and a stripping section. Light hydrocarbon feedstock enters the catalytic distillation column, where 5-20% by mass of benzene and cycloalkanes undergo isomerization in the light hydrocarbon isomerization reaction section. After separation in the rectification section, C5 alkanes and polymethyl C6 isoalkanes are obtained at the top of the column. A side stream from the rectification section is drawn into the aromatization reaction zone for aromatization. The reaction products from the aromatization reaction zone are returned to the catalytic distillation column as recycled material. Then, 80-95% by mass of benzene and cycloalkanes in the light hydrocarbon feedstock, along with other heavy components, pass through the stripping section and enter the cycloalkanes isomerization reaction zone for benzene saturation and cycloalkanes isomerization. The resulting liquid product, obtained after gas-liquid separation, is mixed with the top product from the catalytic distillation column to obtain a high-octane gasoline blending component. The light hydrocarbon feedstock consists of C5-C8 alkanes, cycloalkanes, and aromatics.

2. The method for producing gasoline blending components according to claim 1, characterized in that, The light hydrocarbon raw material consists of 20-80% by mass of C5-C8 alkanes, 0-50% by mass of cycloalkanes, and 1-50% by mass of benzene, with the cycloalkanes content not being 0.

3. The method for producing gasoline blending components according to claim 1 or 2, characterized in that, The cycloalkane isomerization reaction zone is located outside the catalytic distillation column, the feed point of the catalytic distillation column is located in the light hydrocarbon isomerization reaction section, and the recycled material from the aromatization reaction zone returns to the catalytic distillation column in the stripping section.

4. The method for producing gasoline blending components according to claim 3, characterized in that, Based on the total number of trays in the catalytic distillation column, the trays in the rectification section account for 25-50%, the trays in the light hydrocarbon isomerization reaction section account for 40-60%, and the trays in the stripping section account for 5-35%.

5. The method for producing gasoline blending components according to claim 1 or 2, characterized in that, The cycloalkane isomerization reaction zone is located inside the catalytic distillation column, which, from top to bottom, includes a rectification section, a light hydrocarbon isomerization reaction section, a first stripping section, a cycloalkane isomerization reaction zone, and a second stripping section.

6. The method for producing gasoline blending components according to claim 5, characterized in that, Based on the total number of trays in the catalytic distillation column, the trays in the rectification section account for 25-50%, the trays in the light hydrocarbon isomerization reaction section account for 35-65%, the trays in the cycloalkane isomerization reaction zone account for 10-35%, and the tray ratios of the first stripping section and the second stripping section are each 0-25%, with the total number of trays in both the first and second stripping sections not being zero.

7. The method for producing gasoline blending components according to claim 6, characterized in that, The number of trays in the rectification section accounts for 30-40%, the number of trays in the light hydrocarbon isomerization reaction section accounts for 50-55%, and the number of trays in the cycloalkane isomerization reaction section accounts for 10-15%.

8. The method for producing gasoline blending components according to claim 1 or 2, characterized in that, The catalytic distillation column operates at a pressure of 0.2 MPa-5.0 MPa, with a top temperature of 60℃-150℃, a bottom temperature of 200℃-300℃, a side stream extraction temperature of 120℃-240℃, and a feed mass hourly space velocity of 0.2-10.0 h⁻¹. -1 The hydrogen / hydrocarbon molar ratio is 0.1-6.

0.

9. The method for producing gasoline blending components according to claim 8, characterized in that, The catalytic distillation column operates at a pressure of 0.5-5 MPa, with a top temperature of 80℃-140℃, a bottom temperature of 200-280℃, a side stream extraction temperature of 140-200℃, and a feed mass hourly space velocity of 0.5-5.0 h⁻¹. -1 The hydrogen / hydrocarbon molar ratio is 0.5-5.

0.

10. The method for producing gasoline blending components according to claim 8, characterized in that, The reaction temperature of the light hydrocarbon isomerization reaction section is 100~250℃.

11. The method for producing gasoline blending components according to claim 10, characterized in that, The reaction temperature of the light hydrocarbon isomerization reaction section is 160~190℃.

12. The method for producing gasoline blending components according to claim 1 or 2, characterized in that, The light hydrocarbon isomerization reaction section is filled with a solid superacid catalyst, which includes a zirconium dioxide support containing sulfate and a noble metal supported thereon.

13. The method for producing gasoline blending components according to claim 12, characterized in that, Based on the support, the solid superacid catalyst contains 0.5-5.0% sulfur by mass and 0.1-5.0% precious metal by mass, wherein the precious metal is selected from platinum or palladium.

14. The method for producing gasoline blending components according to claim 1 or 2, characterized in that, The reaction temperature in the cycloalkane isomerization reaction zone is 180~350℃, the reaction pressure is 0.1~5.0MPa, and the feed mass hourly space velocity is 0.2~10.0h. -1 The hydrogen / hydrocarbon molar ratio is 0.1~6.

0.

15. The method for producing gasoline blending components according to claim 14, characterized in that, The reaction temperature in the cycloalkane isomerization reaction zone is 200~250℃, the reaction pressure is 0.2~3.0MPa, and the feed mass hourly space velocity is 0.5~5.0h. -1 The hydrogen / hydrocarbon molar ratio is 0.5~5.

0.

16. The method for producing gasoline blending components according to claim 1 or 2, characterized in that, The cycloalkane isomerization reaction zone is filled with a zeolite-type catalyst.

17. The method for producing gasoline blending components according to claim 16, characterized in that, The zeolite catalyst comprises 0.01-2.0% by mass of a noble metal and 97.5-99.9% by mass of a support, wherein the support comprises 10-90% by mass of zeolite and 10-90% by mass of alumina, wherein the noble metal is selected from platinum or palladium, and the zeolite is selected from mordenite, β-zeolite, or a mixture thereof.

18. The method for producing gasoline blending components according to claim 1 or 2, characterized in that, The aromatization reaction zone has a reaction temperature of 380-550℃, a reaction pressure of 0.1-5.0 MPa, and a feed mass hourly space velocity of 0.2-10.0 h⁻¹. -1 The hydrogen / hydrocarbon molar ratio is 0.1-10.

19. The method for producing gasoline blending components according to claim 18, characterized in that, The aromatization reaction zone is characterized by a reaction temperature of 400–500℃, a reaction pressure of 0.2–3.0 MPa, and a feed mass hourly space velocity of 0.5–5.0 h⁻¹. -1 The hydrogen / hydrocarbon molar ratio is 0.5 to 8.

0.

20. The method for producing gasoline blending components according to claim 1 or 2, characterized in that, The aromatization reaction zone is filled with an aromatization catalyst, which includes KL zeolite and Pt supported thereon in a content of 0.1 to 1.5% by mass based on KL zeolite.

21. The method for producing gasoline blending components according to claim 20, characterized in that, The aromatization catalyst also contains 0.5 to 2.0% by mass of halogen.

22. The method for producing gasoline blending components according to claim 21, characterized in that, The halogen is fluorine and / or chlorine.

23. The gasoline blending component obtained by the method for producing gasoline blending components according to any one of claims 1-22.

24. A reaction apparatus for producing gasoline blending components, used in the method for producing gasoline blending components according to any one of claims 1-22, characterized in that, The catalytic distillation column comprises, from top to bottom, at least a rectification section, a light hydrocarbon isomerization reaction section, and a stripping section; the catalytic distillation column is connected to the inlet of the aromatization reaction zone via a side feed pipeline, and the outlet of the aromatization reaction zone is connected to the catalytic distillation column via a circulating material pipeline; the bottom of the catalytic distillation column is connected to the inlet of the cycloalkane isomerization reaction zone; and the outlet of the cycloalkane isomerization reaction zone is connected to a gas-liquid separator.

25. The reaction apparatus for producing gasoline blending components according to claim 24, characterized in that, The light hydrocarbon isomerization reaction section is filled with a solid superacid catalyst, the cycloalkane isomerization reaction zone is filled with a zeolite-type catalyst, and the aromatization reaction zone is filled with an aromatization catalyst.

26. The reaction apparatus for producing gasoline blending components according to claim 24 or 25, characterized in that, The feed position of the catalytic distillation tower is located in the light hydrocarbon isomerization reaction section, and the recycled material from the aromatization reaction zone returns to the catalytic distillation tower at the part below the light hydrocarbon isomerization reaction section.

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