A method and apparatus for increasing the octane number of catalytic gasoline

Abstract

This invention discloses a method and apparatus for increasing the octane number of catalytic gasoline. The method includes: (1) catalytic gasoline entering the feed side of a wall separator; extracting the liquid distillate of heavy components above a certain sensitive plate temperature in the stripping section of the feed side to obtain heavy components of catalytic gasoline; (2) forming a microemulsion with a complexing solvent; (3) mixing the obtained microemulsion with a cooled refrigerant, and performing a complexation reaction on the mixture; (4) centrifuging the effluent from the complexation reaction into a three-phase centrifuge to obtain complexed heavy components of catalytic gasoline; (5) returning the obtained complexed heavy components of catalytic gasoline to the feed side of the wall separator after washing in a solvent washing tower; (6) obtaining gasoline components with increased octane number at the bottom of the wall separator. The method of this invention effectively improves the octane number of catalytic gasoline and significantly improves the efficiency of the complexation reaction, showing good application prospects.

Description

Technical Field

[0001] This invention relates to a method for the directional separation of chemical components, specifically a method for increasing the octane number of catalytic cracking gasoline. Background Technology

[0002] The development of automotive gasoline is moving towards cleaner products, including reducing the content of sulfur, olefins, aromatics, and benzene, increasing octane rating, and reducing the amount of metal additives. Octane rating is an indicator of gasoline's anti-knock properties and a crucial factor in evaluating gasoline quality. Currently, methods to increase gasoline octane rating include: firstly, selecting high-quality feedstocks and processing technologies, such as catalytic cracking and light gasoline etherification, hydrotreating, and reforming (secondary processing); secondly, adding anti-knock agents or high-octane components. Anti-knock agents mainly include MMT, MTBE, aniline, methanol, and ethanol, while high-octane components include isooctane, cumene, and alkylbenzene. However, adding anti-knock agents also presents some problems: MMT is too expensive, MTBE increases the water content in gasoline, and methanol and ethanol can alter the distillation range of the fuel, increasing fuel consumption.

[0003] Due to the structure of my country's refining and chemical industry, most of the gasoline used in vehicles comes from catalytic cracking gasoline. The typical volumetric composition of catalytic cracking gasoline is as follows:

[0004]

[0005] Components n-Pentane n-Hexane n-Heptane n-Octane n-Nonane Octane number 62 25 0 -17 -45

[0006] Catalytic cracked gasoline typically has an octane number of around 89. As can be seen from the table above, n-alkanes are the components with the lowest octane number in catalytic gasoline. If the n-alkanes in catalytic gasoline can be effectively extracted, the octane number of catalytic gasoline can be effectively increased.

[0007] Pure urea crystals are tetragonal. When straight-chain molecules (such as n-alkanes, straight-chain fatty acids, straight-chain fatty alcohols, straight-chain fatty ketones, and straight-chain esters) dissolve in urea solution, hexagonal prism-shaped complexes containing straight-chain molecules precipitate as the temperature decreases. In the urea complex, with the n-alkane as the central axis, the oxygen atom in one urea molecule is connected to the amino group in another urea molecule by hydrogen bonds, forming a helical link that surrounds the straight-chain molecule-guest molecule. Because the diameter of the hollow orbitals formed by the helical urea molecule is between 0.55 and 0.58 nm, the number and types of branches of the guest molecule are limited. For unbranched n-alkanes, at least 6 carbon atoms are required, while for methyl substitution, at least 6 carbon atoms are required to form a straight chain to form a stable complex at room temperature. For n-alkenes and n-alkanes with the same number of carbon atoms, the presence of double bonds in n-alkenes makes the complexes formed by n-alkenes and urea less stable than those formed by n-alkanes and urea. Therefore, the complex formed by 6-carbon n-olefins and urea at room temperature is unstable. Branched molecules, due to the presence of branches, have increased volume and are not easily complexed by urea; the more branches there are, the greater this volume change, and the more difficult it is to complex with urea. Long-chain n-alkanes can form stable complexes with urea molecules through the dispersion forces of van der Waals attraction and electrostatic forces, and the complexes crystallize out at low temperatures. Using this principle, n-alkanes and iso-alkanes can be separated. Filtration first yields the complex crystals formed by n-alkanes and urea, and then decomplexing yields higher-purity n-alkanes. By utilizing the selective complexation of urea molecules on mixed hydrocarbons, the separation of n-alkanes and iso-alkanes can be achieved.

[0008] CN 107779221A discloses a method for separating n-alkanes from gasoline to increase the octane number of gasoline. The method includes the following steps: gasoline is separated into light and heavy components to obtain light component oil and heavy component oil; the heavy component oil is mixed with a complexing agent solution to undergo a complexation reaction, and filtered to obtain a liquid phase product and a solid phase product; the liquid phase product is washed with water to obtain an oil phase product; the light component oil and the oil phase product are mixed to obtain the product oil, thus increasing the octane number of the gasoline. The complexing agent solution uses thiourea, biuret, or a mixture of biuret / urea and any one of thiourea, biuret, and biuret; the solvent in the complexing agent solution is ethanol, a 95% (w / w) aqueous solution of ethanol, methanol, propanol, butanol, acetone, or butanone. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides a method and apparatus for increasing the octane number of catalytic gasoline, specifically involving the complexation, separation, and extraction of n-alkanes within catalytic gasoline.

[0010] According to a first aspect of the present invention, the present invention provides a method for increasing the octane number of catalytic gasoline.

[0011] The method for increasing the octane number of catalytic gasoline provided by the present invention includes the following steps:

[0012] (1) Catalytic (cracking) gasoline enters the feed side of the wall separator through the feed inlet of the wall separator; the heavy component liquid distillate above a certain sensitive plate temperature in the stripping section of the catalytic gasoline feed inlet side is completely or partially extracted to obtain the heavy component of catalytic gasoline; the temperature of the sensitive plate is 60-100℃;

[0013] (2) The catalytic gasoline heavy components obtained in step (1) are forcibly mixed with the complexing solvent to form a microemulsion;

[0014] (3) After the microemulsion obtained in step (2) is cooled, it is mixed with the refrigerant that has been cooled by the compressor. The mixed material enters the reactor for complexation reaction. The complexation reaction reactor adopts a tubular reactor structure.

[0015] (4) The complex reaction effluent obtained in step (3) is centrifuged in a three-phase centrifuge. The liquid is centrifuged and separated into layers inside, the gas is directly discharged, and the solid is centrifuged to the outermost layer and falls to the bottom under the action of gravity. After passing through the three-phase centrifuge, the gaseous refrigerant, the complexed solvent after the reaction, the complexed catalytic gasoline heavy components and the complex solid are obtained.

[0016] (5) The complexed catalytic gasoline heavy components obtained in step (4) are washed in a solvent washing tower and then returned to the feed side of the wall separator;

[0017] (6) Light hydrocarbon components are obtained at the top of the wall separator, gasoline components with increased octane number are obtained at the bottom of the wall separator, and solvent is obtained in the middle of the wall separator.

[0018] Furthermore, the method of the present invention also includes step (7): the gaseous refrigerant obtained in step (4) leaves from the top of the three-phase centrifugal separator and enters the centrifugal compressor, is compressed and cooled into a liquid and then returns to step (3), and is mixed again with the complexed solvent.

[0019] Furthermore, the method of the present invention also includes step (8): the complex solid obtained in step (7) is discharged from the lower part of the three-phase centrifuge and dissolved by heating to precipitate oil rich in n-alkanes.

[0020] Furthermore, it also includes step (9): the complexed solvent obtained after the cold reaction in step (4) is centrifuged into the inner liquid layer under the action of centrifugal force in a three-phase centrifuge, and leaves through the upper part of the centrifuge. After being heated, it returns to step (2) and is forced to react with the uncomplexed catalytic gasoline heavy components extracted from the wall separation tower.

[0021] Furthermore, after solvent washing in step (5), the catalytic gasoline heavy components are returned to the next tray below the extraction layer of the separator.

[0022] Furthermore, the light hydrocarbon components obtained at the top of the wall-breaking tower in step (6) mainly refer to the C1-C4 components. The obtained solvent can be recycled and used as a supplement for complexing solvents.

[0023] Furthermore, the partition tower is an intermediate partition tower, comprising an insulating partition, an upper common area, a lower common area, a first partition area, and a second partition area.

[0024] Furthermore, the first partition zone includes a feed inlet, an extraction outlet, an extraction return outlet, a complexed gasoline return outlet, a first partition zone rectification section, and a first partition zone stripping section.

[0025] Furthermore, the second partition zone includes a solvent extraction outlet and a distillation section of the second partition zone.

[0026] Furthermore, the complexing solvent can be selected from conventional complexing solvents in the art. A typical complexing solvent includes a complexing agent and a solvent. The mass fraction of the complexing agent in the complexing solvent is generally 5%-20%. The complexing agent is urea or a mixture of urea and thiourea. The solvent is selected from the group consisting of ethanol, a 95% aqueous solution of ethanol, methanol, propanol, and isopropanol, preferably ethanol or a 95% aqueous solution of ethanol. Preferably, the complexing solvent also includes a solubilizer. The solubilizer consists of isoamyl alcohol and fatty alcohol. The fatty alcohol is selected from the group consisting of monohydric and polyhydric fatty alcohols, and the mass fraction of the solubilizer in the complexing solvent is 0.5%-1%.

[0027] Furthermore, the refrigerant is immiscible with the complexing solvent. The refrigerant is selected from conventional refrigerants in the art, preferably R22.

[0028] Furthermore, the operating conditions for the split-wall column are as follows: the bottom temperature is preferably 140℃-180℃, and the top temperature is preferably 30℃-60℃.

[0029] Furthermore, the temperature of the trays extracted in step (1) is preferably 60℃-100℃.

[0030] Furthermore, the forced mixing in step (2) is performed using mechanical stirring. The mixing temperature is preferably 60℃-100℃, and the pressure is preferably 0.1MPa-2MPa.

[0031] Furthermore, in step (3), the complexation reactor is a tubular reactor well known in the art. The conditions for the complexation reaction are generally: temperature of -5℃ to 20℃, pressure of 0MPa to 2MPa, and agent-to-oil volume ratio of 0.5 to 10.

[0032] Furthermore, the structure of the three-phase centrifuge in step (4) is a structure well known in the art. The conditions for centrifugal separation are: temperature of -5℃ to 20℃ and pressure of 0MPa to 2MPa.

[0033] Furthermore, in step (5), the solvent washing tower extracts some of the complexing agent dissolved in the gasoline. The washing solvent enters from the top of the washing tower and comes into countercurrent contact with the gasoline coming from the bottom of the tower, thus extracting the complexing agent in the gasoline.

[0034] Further, in step (6), the catalytic gasoline feed enters the fractionation tower, which simultaneously provides stability, fractionation of light and heavy components, and removal of complexed solvent components from the gasoline. The feed is first fractionated in the first partition zone, which is used to separate the light and heavy components of the gasoline, with the heavier components at the bottom and the lighter components at the top. The temperature of the trays near the feed line is controlled at approximately 40-60°C. The side line of the heavy component gasoline is used to extract the fractionated heavy components of the gasoline to be complexed. The solvent-washed complexed heavy component gasoline is returned to the complexed heavy component gasoline. The tray sensitive temperature is approximately 60-100°C. The second partition zone is used to separate the complexed solvent brought into the fractionation tower by the complexed heavy component gasoline. The vapor from the bottom of the tower and the cold reflux from the upper common area come into countercurrent contact. The solvent dissolved in the solvent-washed gasoline is concentrated and purified in the trays near the solvent side line of the solvent extraction line and leaves the fractionation tower through the solvent side line of the solvent extraction line. The rising steam from the first and second partition walls enters the upper common area and comes into countercurrent contact with the cold reflux returning from the cold reflux line. The overhead gas is extracted through the overhead extraction line. Part of it enters the overhead condenser for condensation and then enters the reflux tank before returning to the tower through the cold reflux line. The other part is discharged through the overhead non-condensable steam line. The overhead pressure is controlled at 0.1-0.8 MPa, and the cold reflux return temperature is controlled at 30-60℃. The gasoline at the bottom of the wall separator is heated by the wall separator bottom reboiler, and the temperature is maintained between 140-180℃. Part of the gasoline is extracted through the high-octane gasoline extraction line.

[0035] According to a second aspect of the present invention, the present invention provides a device for increasing the octane number of catalytic gasoline.

[0036] The catalytic gasoline octane number enhancement device of the present invention includes:

[0037] The wall-mounted tower is a middle-partitioned wall-mounted tower; the wall-mounted tower includes an insulating partition, an upper common area, a lower common area, a first partition zone, and a second partition zone; the first partition zone includes a feed inlet, an extraction outlet, a gasoline return outlet after complexation, a rectification section of the first partition zone, and a stripping section of the first partition zone.

[0038] A stirrer is used to achieve forced mixing of extracted heavy components of catalytic gasoline and complexed solvents to form a microemulsion;

[0039] A tubular complexing reactor, which is used to carry out a complexing reaction between a mixture of refrigerant and microemulsion;

[0040] A three-phase centrifugal separator is used to separate complexed materials into gaseous refrigerant, complexed solvent after reaction, complexed catalytic gasoline heavy components and complex solids.

[0041] Compressors and condensers are used to compress gaseous refrigerant and condense it into liquid refrigerant;

[0042] The solvent washing tower is used to wash unreacted catalytic gasoline components with solvent and feed the washed gasoline components to the extraction return port of the wall separator.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. In this invention, a wall-mounted column is used for the fractionation of catalytic gasoline and the extraction of solvents from the catalytic gasoline after complexation. Only one column is needed to complete the fractionation of catalytic gasoline and the purification of the gasoline after complexation.

[0045] 2. In this invention, a refrigerant that is completely insoluble with the complexing solvent and catalytic gasoline is used to directly form a microemulsion mixture system with the catalytic gasoline and the complexing solvent. This results in rapid cooling without the need for a heat exchange process, avoiding problems such as wall crystallization. It is highly efficient, fast, and meets the requirements for long-term operation.

[0046] 3. In this invention, it is preferable to add a solubilizer to the complexing solvent. The use of the solubilizer significantly reduces the interfacial tension between the complexing solvent and the catalytic gasoline, accelerates the formation of the microemulsion system, and thus improves the reaction efficiency.

[0047] 4. In this invention, a microemulsion system is formed by catalytic gasoline and complexing solvent for complexation. The microemulsion system has a large interface area, and the complexation reaction mainly occurs at the interface, resulting in a thorough and rapid complexation process. Attached image description:

[0048] Figure 1 This is a flowchart illustrating the method of the present invention.

[0049] Figure 2 This is a schematic diagram of a split-wall tower.

[0050] Figure 3 This is a schematic diagram of a three-phase centrifugal separator.

[0051] Figure 4 This is a schematic diagram of a stirrer.

[0052] Figure 1-4In the diagram, the numbers correspond to the following: 1-Feed line; 2-Cold reflux line; 3-Reflux tank; 4-Top condenser; 5-Top non-condensable vapor line; 6-Top extraction line; 7-Insulating partition; 8-Solvent side extraction line; 9-Heavy component gasoline side extraction line; 10-Complexed gasoline return line; 11-Compressor; 12-Refrigerant condenser; 13-Refrigerant vapor phase extraction line; 14-Cold gasoline extraction line; 15-Cold complexed solvent extraction line; 16-Three-phase centrifuge; 17-Solid phase extraction line; 18-Three-phase centrifuge feed line; 19-Rotating shaft; 20-Mixer; 21- 21-Complexed microemulsion cooler; 22-Solvent washing tower; 23-Washing solvent feed line; 24-Post-wash gasoline heater; 25-High octane gasoline extraction line; 26-Bottom reboiler of the dividing wall tower; 27-Second partition zone; 28-First partition zone; 29-Upper common zone; 30-Lower common zone; 31-Agitator; 32-Microemulsion extraction outlet; 33-Agitator impeller; 34-Dividing wall tower; 35-Cold post-complexed solvent heater; 36-Hot post-complexed solvent inlet; 37-Post-complexed gasoline heater; 38-Tube reactor; 39-First partition zone stripping section; 40-First partition zone rectification section. Detailed Implementation

[0053] The method of the present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments.

[0054] like Figure 1-4 As shown, the catalytic gasoline octane number enhancement device of the present invention includes: a partitioned column 34, which is an intermediate partitioned column; the partitioned column 34 includes an adiabatic partition 7, an upper common area, a lower common area, a first partitioned column 28, and a second partitioned column 27; the first partitioned column includes a feed inlet line, a gasoline side line extraction outlet 9, a complexed gasoline return outlet 10, a first partitioned column rectification section 40, and a first partitioned column stripping section 39;

[0055] A stirrer 31 is used to achieve forced mixing of extracted heavy components of catalytic gasoline and complexing solvent to form a microemulsion; the stirrer 31 includes a stirring impeller 33, a microemulsion extraction outlet 32, a post-heated complexing solvent inlet 36, and a heavy component feed inlet of catalytic gasoline.

[0056] Tubular complexing reactor 18, which is used to supply a mixture of refrigerant and microemulsion for complexing reaction;

[0057] Three-phase centrifugal separator 16 is used to separate complexed materials into gaseous refrigerant, complexed solvent after reaction, complexed catalytic gasoline heavy components and complex solids; the three-phase centrifugal separator 16 includes a rotating shaft 19, a refrigerant gas phase extraction line 13, a complexed gasoline extraction line 14, a solid phase extraction line 17, and a cooled complexed solvent extraction line 15.

[0058] The compressor 11 and the condenser 12 are used to compress the gaseous refrigerant and condense it into a liquid refrigerant;

[0059] Solvent washing tower 22 is used to perform solvent washing on complexed catalytic gasoline heavy components and feed the washed gasoline components to the extraction return port 10 of the wall separation tower.

[0060] Combination Figure 1-4 As shown, the method for increasing the octane number of catalytic gasoline according to the present invention includes the following:

[0061] The temperature at the inlet of the first partition wall zone 28 of the wall separator 34 is 40-60℃. Catalytic gasoline flows downward in the first partition wall zone 28 and is fractionated. When it reaches the side line extraction line 9 of the heavy component gasoline, the gasoline composition is mainly heavy component. The temperature of the heat-sensitive plate at the side line extraction line 9 of the heavy component gasoline in the first partition wall zone 28 of the wall separator 34 is 60-100℃. The heavier catalytic gasoline is extracted from the side line extraction line 9 of the heavy component gasoline and enters the stirrer 31.

[0062] The cooled complexing solvent is extracted from the cooled complexing solvent extraction line 15 of the three-phase offline separator 16 and sent into the cooled complexing solvent heater 35 to be heated to 60-100°C before entering the stirrer 31.

[0063] After being heated by the cooled complexing solvent heater 35, the heated complexing solvent enters the stirrer 31 through the complexing solvent inlet 36. Inside the stirrer 31, the heated complexing solvent and the heavier catalytic gasoline are rapidly stirred by the stirring impeller 33 to form a microemulsion. The entire process can be completed within 1-10 minutes. The stirred microemulsion leaves the stirrer 31 through the microemulsion outlet 32 ​​and enters the complexing microemulsion cooler 21 to be cooled to 30-40°C, becoming a cooled microemulsion. The cooled microemulsion enters the mixer 20 and mixes with the liquid refrigerant R22 from the refrigerant condenser 12 to become a refrigerated mixed solvent. The refrigerated mixed solvent first enters the tubular reactor 38, where it flows rapidly, cools, and crystallizes. After the reaction, it all enters the three-phase centrifuge 16.

[0064] Inside the three-phase centrifuge 16, the pressure is controlled between 0.2 and 0.4 MPa. The R22 in the refrigerant mixture evaporates and absorbs heat, maintaining the temperature inside the centrifuge 16 at 0-10℃. At this low temperature, the complexing agent in the complexing solvent complexes the n-alkane and precipitates it as a solid. This solid precipitate is then thrown to the bottom edge by the centrifugal force of the centrifuge 16 and extracted through the solid phase extraction line 17. The refrigerant R22 evaporates into a gaseous state inside the three-phase centrifuge 16 and leaves the centrifuge 16 through the refrigerant gas phase extraction line 13, entering the compressor 11 where it is compressed to 1.5-2 MPa. After passing through MPa, the refrigerant enters the refrigerant condenser 12 and is condensed into a liquid state, returning to the mixer 20 for reuse. Under the centrifugal force of the three-phase separator 16, the complexed gasoline and the complexed solvent are separated by centrifugal force. The complexed gasoline is drawn from the cooled gasoline extraction line 14 and enters the complexed gasoline heater 37 to be heated to 60-90°C, becoming hot complexed gasoline. The complexed solvent is drawn from the cooled complexed solvent extraction line 15, becoming cooled complexed solvent, and further enters the cooled complexed solvent heater 35 to be heated to 40-60°C, becoming hot complexed solvent. The hot complexed solvent returns to the stirrer 31 for reuse.

[0065] After hot complexation, gasoline enters the solvent washing tower 22 from bottom to top and is washed by countercurrent contact with the solvent from the washing solvent feed line 23. After washing, the gasoline becomes solvent-washed gasoline and returns to the wall separation tower from the gasoline return line 10.

[0066] Inside the fractionation tower 34, ambient temperature catalytic gasoline is fractionated in the first partition 28: heavier components are at the bottom and lighter components at the top. The tray temperature near the catalytic gasoline feed line 1 in the fractionation tower 34 is controlled at approximately 40-60°C, while the tray temperature near the heavy component gasoline side-stream extraction line 9 and the complexed gasoline return line 10 is approximately 60-100°C. The heavy component gasoline side-stream extraction line 9 extracts the heavier catalytic gasoline components. In the second partition zone 27, the vapor from the bottom of the tower and the cold reflux from the upper common zone 29 come into countercurrent contact. The solvent dissolved in the solvent-washed gasoline is concentrated and purified in the tray near the solvent side-stream extraction line 8 and leaves the fractionation tower 34 via the solvent side-stream extraction line 8. The rising steam from the first partition zone 28 and the second partition zone 27 enters the upper common zone 29 and comes into countercurrent contact with the cold reflux returning from the cold reflux line 2; the top gas is extracted through the top extraction line 6, part of which enters the top condenser 4 for condensation and then enters the reflux tank 3 before returning to the tower through the cold reflux line 2, and the other part is discharged through the top non-condensable steam line 5. The top pressure is controlled at 0.1-0.8 MPa, and the cold reflux return temperature is controlled at 30-45℃; the gasoline at the bottom of the dividing column 31 is heated by the dividing column bottom reboiler 26, and the temperature is maintained between 120-150℃, and part of the gasoline is extracted through the high octane gasoline extraction line 25.

[0067] The octane rating of the high-octane gasoline extracted from the bottom of the dividing tower 34 can be controlled by the extraction rate of the heavy component gasoline side line extraction line 9. A larger extraction rate of the side line extraction line 9 results in a higher octane rating of the high-octane gasoline extracted from the bottom of the tower. This technology can increase the gasoline octane rating by more than 20.

[0068] Example 1

[0069] The above process flow is adopted: the raw material is a certain catalytic gasoline, and its mass composition is shown in the table (unit: wt%):

[0070]

[0071] Feed temperature 50℃; raw material separation temperature in the separator 90℃; mass composition of heavy components after separation in the separator (unit: wt%):

[0072]

[0073] Inside the agitator: the volume ratio of the complexing solvent to the gasoline components to be complexed is 2:1; the mass ratio of each component in the complexing solvent is: M complexing agent : M solubilizer : M solvent = 10 : 1 : 89; the residence time in the agitator is approximately 10 seconds. The complexing agent is urea, the solubilizer is isoamyl alcohol and a monohydric fatty alcohol, and the solvent is 95% anhydrous ethanol.

[0074] Inside the tubular reactor: reaction temperature around 5℃, volume hourly space velocity 6000 h⁻¹ -1 .

[0075] Three-phase centrifuge: operating temperature around 0℃-5℃, pressure 0.2MPa (A).

[0076] After complexation, the mass composition of the complexing solution is as follows (unit: wt%):

[0077]

[0078] The mass composition of the complexed gasoline components is as follows (unit: wt%):

[0079]

[0080] Octane number change: After complexation, the mass of the heavy gasoline component accounts for 51% of the feed mass. The octane number of the heavy gasoline component after complexation increases from 84 to 96, and the overall octane number of the catalytic gasoline increases from 89 to 95.

[0081] Example 2

[0082] The raw materials, complexing agent, and solvent are the same as in Example 1; the mass ratio of the complexing solvent composition is: complexing agent: solvent = 10:90, with no solubilizer.

[0083] Feed temperature 50℃; raw material separation temperature in the separator 90℃; mass composition of heavy components after separation in the separator (unit: wt%):

[0084]

[0085] The residence time in the stirrer is approximately 20 minutes. In the tubular reactor, the reaction temperature is approximately 5°C, and the volume hourly space velocity is 6000 h⁻¹. -1 Three-phase centrifuge: operating temperature around 0℃-5℃, pressure 0.2MPa.

[0086] Inside the tubular reactor: reaction temperature around 5℃, volume hourly space velocity 6000 h⁻¹ -1 .

[0087] Three-phase centrifuge: operating temperature around 0℃-5℃, pressure 0.2MPa (A).

[0088] After complexation, the mass composition of the complexing solution is as follows (unit: wt%):

[0089]

[0090] The mass composition of the complexed gasoline components is as follows (unit: wt%):

[0091]

[0092] Octane number change: After complexation, the mass of the heavy gasoline component accounts for 51% of the feed mass. After complexation, the octane number of the heavy gasoline component increases from 84 to 93, and the overall octane number of the catalytic gasoline increases from 89 to 93.

[0093] Example 3

[0094] The raw material is the same as in Example 1, which is a certain catalytic gasoline. Its mass composition is the same as in Example 1, as shown in the table (unit: wt%):

[0095]

[0096] Feed temperature 50℃; raw material separation temperature in the separator 100℃; mass composition of heavy components after separation in the separator (unit: wt%):

[0097]

[0098] Inside the agitator: the volume ratio of the complexing solvent to the gasoline components to be complexed is 2:1; the mass ratio of each component in the complexing solvent is: M complexing agent : M solubilizer : M solvent = 10 : 1 : 89; the residence time in the agitator is approximately 10 seconds. The complexing agent is urea, the solubilizer is isoamyl alcohol and a monohydric fatty alcohol, and the solvent is 95% anhydrous ethanol.

[0099] Inside the tubular reactor: reaction temperature around 5℃, volume hourly space velocity 6000 h⁻¹ -1 .

[0100] Three-phase centrifuge: operating temperature around 0℃-5℃, pressure 0.2MPa (A).

[0101] After complexation, the mass composition of the complexing solution is as follows (unit: wt%):

[0102]

[0103] The mass composition of the complexed gasoline components is as follows (unit: wt%):

[0104]

[0105] Octane number change: After complexation, the mass of the heavy gasoline component accounts for 42% of the feed mass. The octane number of the heavy gasoline component after complexation increases from 86 to 98, and the overall octane number of the catalytic gasoline increases from 89 to 94.

Claims

1. A method for increasing the octane number of catalytic gasoline, comprising the following steps: (1) Catalytic gasoline enters the feed side of the wall separator through the feed inlet of the wall separator; the heavy component liquid distillate above a certain sensitive plate temperature in the stripping section of the catalytic gasoline feed inlet side is completely or partially extracted to obtain the heavy component of catalytic gasoline; the temperature of the sensitive plate is 60-100℃; (2) The catalytic gasoline heavy components obtained in step (1) are forcibly mixed with the complexing solvent to form a microemulsion; (3) After the microemulsion obtained in step (2) is cooled, it is mixed with the refrigerant after being cooled by the compressor. The mixed material enters the reactor for complexation reaction. (4) The complexation reaction effluent obtained in step (3) is centrifuged in a three-phase centrifuge. After passing through the three-phase centrifuge, the gaseous refrigerant, the complexed solvent after reaction, the complexed catalytic gasoline heavy components and the complex solid are obtained. (5) The complexed catalytic gasoline heavy components obtained in step (4) are washed in a solvent washing tower and then returned to the feed side of the wall separator; (6) Light hydrocarbon components are obtained at the top of the wall separator, gasoline components with increased octane number are obtained at the bottom of the wall separator, and solvent is obtained in the middle of the wall separator; The complexing solvent includes a complexing agent, a solvent, and a solubilizer. The complexing agent has a mass fraction of 5%-20%, and the solubilizer has a mass fraction of 0.5%-1%. The complexing agent is urea or a mixture of urea and thiourea. The solvent is selected from ethanol, methanol, propanol, or isopropanol. The solubilizer includes isoamyl alcohol and fatty alcohols other than isoamyl alcohol. The refrigerant and the complexing solvent are immiscible.

2. The lifting method according to claim 1, characterized in that, It also includes step (7): the gaseous refrigerant obtained in step (4) leaves from the top of the three-phase centrifugal separator and enters the centrifugal compressor. After being compressed and cooled into a liquid, it returns to step (3) and is mixed with the cooled microemulsion again.

3. The lifting method according to claim 2, characterized in that, It also includes step (8): the complex solid obtained in step (4) is discharged from the bottom of the three-phase centrifuge and dissolved by heating to precipitate oil rich in n-alkane.

4. The lifting method according to claim 1, characterized in that, It also includes step (9): the complexed solvent obtained in step (4) is centrifuged into the inner liquid layer under the action of centrifugal force of the three-phase centrifuge, and leaves through the upper part of the centrifuge. After being heated, it returns to step (2) and is forcibly mixed with the uncomplexed catalytic gasoline heavy components extracted from the wall separation tower.

5. The lifting method according to claim 1, characterized in that, The solvent obtained in step (6) is recycled and used as a supplement to the complexing solvent.

6. The lifting method according to claim 1, characterized in that, The partition tower is a middle partition tower, comprising an insulated partition, an upper common area, a lower common area, a first partition area, and a second partition area.

7. The lifting method according to claim 6, characterized in that, The second partition zone includes a solvent extraction outlet and a distillation section.

8. The lifting method according to claim 1, characterized in that, The refrigerant is R22.

9. The lifting method according to claim 1, characterized in that, The operating conditions of the split-wall tower are: bottom temperature of 140℃-180℃ and top temperature of 30℃-60℃.

10. The lifting method according to claim 1, characterized in that, The mixing temperature in step (2) is 60℃-100℃ and the pressure is 0.1MPa-2MPa.

11. The lifting method according to claim 1, characterized in that, The reactor in step (3) is a tubular reactor; the conditions for the complexation reaction are: temperature -5℃ to 20℃, pressure 0MPa to 2MPa, and agent-to-oil volume ratio 0.5 to 10.

12. The lifting method according to claim 1, characterized in that, The conditions for centrifugation in step (4) are: temperature -5℃ to 20℃, pressure 0MPa to 2MPa.

Images