阅读说明：本技术 处理催化裂解汽油的方法和系统、多产低碳烯烃和轻质芳烃的工艺和装置 (Method and system for treating catalytic pyrolysis gasoline, and process and device for producing light olefins and light aromatics in high yield ) 是由 王迪 魏晓丽 龚剑洪 于敬川 张久顺 于 2019-10-30 设计创作，主要内容包括：本发明涉及一种处理催化裂解汽油的方法和系统、多产低碳烯烃和轻质芳烃的工艺和装置。该方法包括：使来自催化裂解反应单元的催化裂解汽油和/或催化裂解反应油气进行分馏,得到轻汽油、重汽油和可选的其他产物；使所述重汽油进行芳烃抽提,得到苯、甲苯、二甲苯、C9+芳烃和芳烃抽余油；使甲苯与所述C9+芳烃进入流态化反应器与第二催化剂接触并在临氢条件下进行脱烷基和烷基转移耦合反应,得到脱烷基液体产物和第二待生催化剂；使所述脱烷基液体产物与所述重汽油混合后进行所述芳烃抽提。本发明的方法能够使催化裂解汽油高效转化为低碳烯烃和轻芳烃,且多产二甲苯。(The invention relates to a method and a system for treating catalytic pyrolysis gasoline, and a process and a device for producing light olefins and light aromatics in a high yield. The method comprises the following steps: fractionating catalytically cracked gasoline and/or catalytically cracked oil gas from the catalytic cracking reaction unit to obtain light gasoline, heavy gasoline and optional other products; aromatic extraction is carried out on the heavy gasoline to obtain benzene, toluene, xylene, C9+ aromatic hydrocarbon and aromatic raffinate oil; enabling toluene and the C9+ aromatic hydrocarbon to enter a fluidized reactor to contact with a second catalyst and carrying out dealkylation and transalkylation coupling reaction under the hydrogen condition to obtain a dealkylated liquid product and a second spent catalyst; and mixing the dealkylation liquid product with the heavy gasoline, and then extracting the aromatic hydrocarbon. The method can efficiently convert the catalytic pyrolysis gasoline into low-carbon olefin and light aromatic hydrocarbon and produce more dimethylbenzene.)

1. A method of treating a catalytic pyrolysis gasoline, the method comprising:

fractionating catalytically cracked gasoline and/or catalytically cracked oil gas from the catalytic cracking reaction unit to obtain light gasoline, heavy gasoline and optional other products;

aromatic extraction is carried out on the heavy gasoline to obtain benzene, toluene, xylene, C9+ aromatic hydrocarbon and aromatic raffinate oil;

enabling toluene and the C9+ aromatic hydrocarbon to enter a fluidized reactor to contact with a second catalyst and carrying out dealkylation and transalkylation coupling reaction under the hydrogen condition to obtain a dealkylated liquid product and a second spent catalyst; and mixing the dealkylation liquid product with the heavy gasoline, and then extracting the aromatic hydrocarbon.

2. The method of claim 1, further comprising returning the light gasoline to the catalytic cracking reaction unit to continue the catalytic cracking reaction.

3. The method according to claim 1 or 2, wherein the light gasoline has an initial boiling point of 20 to 40 ℃ and an end boiling point of 80 to 100 ℃; the initial boiling point of the heavy gasoline is 80-100 ℃, and the final boiling point of the heavy gasoline is 200-250 ℃.

4. The method of claim 1, further comprising returning the aromatic raffinate to the catalytic cracking reaction unit for continuing the catalytic cracking reaction.

5. The method of claim 1, wherein the dealkylation and transalkylation are carried out at a temperature of 250-710 ℃, a pressure of 0-5.8 MPa, and a weight hourly space velocity of 0.2-6 h^-1The hydrogen/hydrocarbon molar ratio is 1 to 15; preferably, the temperature of the hydrodealkylation reaction is 330-570 ℃, the pressure is 0.1-4.6 MPa, and the weight hourly space velocity is 0.5-5.5 h^-1The hydrogen/hydrocarbon molar ratio is 2-12; more preferably, the temperature of the lightening reaction is 340-540 ℃, the pressure is 1.2-3.8 MPa, and the weight hourly space velocity is 1.2-4 h^-1The hydrogen/hydrocarbon molar ratio is 4 to 8.

6. The method of claim 1, wherein the second catalyst comprises a support and an active metal component supported on the support; the content of the active metal component is 0.01-50 wt% based on the total weight of the second catalyst.

7. The method of claim 6, wherein the carrier comprises, based on the total weight of the carrier: 1 to 60 wt% of zeolite, 5 to 99 wt% of an inorganic oxide and 0 to 70 wt% of clay;

the zeolite comprises a medium pore zeolite and/or a large pore zeolite; the inorganic oxide is at least one of silicon dioxide, aluminum oxide, zirconium oxide, titanium oxide and amorphous silica-alumina; the clay is at least one selected from kaolin, montmorillonite, diatomite, attapulgite, sepiolite, halloysite, hydrotalcite, bentonite and rectorite.

8. The process of claim 7 wherein the intermediate pore zeolite is a ZSM zeolite and/or a ZRP zeolite and the large pore zeolite is selected from one or more of a beta zeolite, a rare earth Y zeolite, a rare earth hydrogen Y zeolite, an ultrastable Y zeolite and a high silicon Y zeolite.

9. The method according to claim 6, wherein the active metal component is one or a combination of two or more of a rare earth metal and a transition metal.

10. The method of claim 1, wherein the method further comprises: and (3) feeding the second spent catalyst into a fluidized bed regenerator for regeneration, and recycling the obtained second regenerated catalyst to the fluidized reactor.

11. The method of claim 10, wherein the fluidized bed regenerator includes a lock hopper, the method of regenerating comprising: and (3) enabling the second spent catalyst to enter the fluidized bed regenerator for regeneration through a lock hopper, and recycling the second regenerated catalyst to the fluidized reactor through the lock hopper.

12. A process for producing light olefins and light aromatics in a high yield comprises the steps of enabling raw oil to contact a first catalyst in a catalytic cracking reactor to conduct catalytic cracking reaction to obtain catalytic cracking reaction oil gas, and treating the catalytic cracking reaction oil gas by the method of any one of claims 1-11.

13. A system for processing catalytic pyrolysis gasoline comprises a catalytic pyrolysis gasoline inlet, a separation unit, an aromatic hydrocarbon extraction unit and a dealkylation and transalkylation coupling reaction unit;

the separation unit comprises separation equipment, and the separation equipment is provided with a first oil-gas inlet, a light gasoline outlet, a heavy gasoline outlet and optional other product outlets; the first oil gas inlet is communicated with the catalytic pyrolysis gasoline inlet; the light gasoline outlet is optionally used for communicating with the inlet of the catalytic cracking reactor;

the aromatic hydrocarbon extraction unit comprises aromatic hydrocarbon extraction and separation equipment, and the aromatic hydrocarbon extraction and separation equipment is provided with a second oil gas inlet, a benzene outlet, a toluene outlet, a xylene outlet, a C9+ aromatic hydrocarbon outlet and an aromatic hydrocarbon raffinate oil outlet; the second oil-gas inlet is communicated with the heavy gasoline outlet of the separation unit; the aromatic raffinate oil outlet is optionally used for communicating with an inlet of a catalytic cracking reactor;

the dealkylation and transalkylation coupling reaction unit comprises a fluidization reactor, the fluidization reactor is provided with a third oil gas inlet and a dealkylation oil gas outlet, the third oil gas inlet is respectively communicated with the toluene outlet and the C9+ aromatic hydrocarbon outlet, and the dealkylation oil gas outlet is communicated with the second oil gas inlet of the aromatic hydrocarbon extraction unit.

14. The system of claim 13, wherein the aromatics extraction and separation device comprises an aromatics extraction device, an aromatics separation column, and a solvent recovery device, the aromatics extraction device having the fourth oil gas inlet, a solvent inlet, an aromatics-solvent mixture outlet, and the aromatics raffinate oil outlet; the solvent recovery equipment is provided with an aromatic hydrocarbon-solvent mixed liquid inlet, an aromatic hydrocarbon outlet and a solvent outlet, and the aromatic hydrocarbon-solvent mixed liquid inlet is communicated with the aromatic hydrocarbon-solvent mixed liquid outlet of the aromatic hydrocarbon extraction equipment; the aromatic hydrocarbon separation tower is provided with a fourth oil gas inlet, the benzene outlet, the toluene outlet, the xylene outlet and the C9+ aromatic hydrocarbon outlet, and the fourth oil gas inlet is communicated with the aromatic hydrocarbon outlet of the solvent recovery equipment.

15. The system of claim 13, wherein the dealkylation and transalkylation coupled reaction unit further comprises a second catalyst regenerator, the second catalyst regenerator being a fluidized bed regenerator with a lock hopper.

16. The system of claim 13, wherein the fluidized reactor is a dilute phase transport bed reactor, a fluidized bed reactor, a composite reactor composed of a dilute phase transport bed reactor and a fluidized bed reactor, a composite reactor composed of two or more dilute phase transport bed reactors, or a composite reactor composed of two or more fluidized bed reactors; the dilute phase conveying bed reactor is a riser reactor; the fluidized bed reactor is a bubbling bed reactor, a turbulent bed reactor or a fast bed reactor; the fluidized reactor is an upflow reactor or a downflow reactor.

17. A device for producing light olefins and light aromatics in a large quantity comprises a catalytic cracking reaction unit and the system of any one of claims 13-16, wherein a reaction oil gas outlet of the catalytic cracking reaction unit is communicated with a catalytic cracking reaction oil gas inlet, a raw material inlet of the catalytic cracking reaction unit is communicated with a light gasoline outlet, and a raw material inlet of the catalytic cracking reaction unit is communicated with an aromatic raffinate oil outlet.

Technical Field

The invention relates to a method and a system for treating catalytic pyrolysis gasoline, and a process and a device for producing light olefins and light aromatics in a high yield.

Background

BTX (benzene, toluene and xylene) is an important petrochemical basic product, is an important raw material of various chemical products such as synthetic rubber, synthetic fiber and synthetic resin, and the toluene and the xylene can also be used as a gasoline octane number additive. The growth of the global aromatic hydrocarbon industrial chain is concentrated in northeast Asia regions under the continuous pulling of the industries of Chinese terylene, polyester and PTA, and the demand of triphenyl is continuously increased. However, the aromatic hydrocarbon production process is accompanied with the production of C9+ heavy aromatic hydrocarbon, the C9+ heavy aromatic hydrocarbon has large yield, low value and limited utilization path, which causes resource waste, the C9+ heavy aromatic hydrocarbon in the catalytic pyrolysis gasoline is converted into BTX, and the low-carbon olefin and the xylene are produced in large quantities, which is undoubtedly an effective method for fully utilizing resources and improving the quality and efficiency of enterprises.

CN97106718.X discloses a heavy aromatics hydrodealkylation and transalkylation process, which comprises using C10 or/and C11 aromatics as raw materials, reacting in a fixed bed reactor at 300-600 ℃ and 1.5-4.0 MPa in the presence of a catalyst of hydrogen-type mordenite loaded with bismuth and at least one metal or oxide selected from iron, cobalt, nickel or molybdenum to produce C6-C9 aromatics and paraffin of C1-C4. The process is especially suitable for hydrodealkylation and transalkylation of heavy aromatics of C10 and/or C10, and can be used in industrial production.

CN200410066625.4 discloses a method for hydrodealkylation and transalkylation of heavy aromatics, which mainly solves the problems in the prior art that the content of heavy aromatics in raw materials is allowed to be lower and the utilization rate of the heavy aromatics is low. The technical scheme that C10 or/and C11 aromatic hydrocarbon is/are used as raw materials, and the macroporous zeolite loaded with metal or oxide of bismuth and molybdenum is used as a catalyst in a fixed bed reactor to react at the temperature of 300-600 ℃ and the pressure of 1.0-4.0 MPa to generate mixed xylene is adopted, so that the problem is solved well. The method has the characteristics of simple flow, high yield of mixed xylene, low hydrogen-hydrocarbon ratio and the like, and can be used for industrial production of mixed xylene from heavy aromatic hydrocarbon.

CN200480040758.2 discloses a process for the catalytic hydrodealkylation alone of hydrocarbons comprising C8-C13 alkylaromatic compounds, optionally mixed with C4-C9 aliphatic and cycloaliphatic products, which comprises treating said hydrocarbon composition continuously with a catalyst consisting of a ZSM-5 zeolite and modified with at least one metal selected from groups IIB, VIB, VIII, in the presence of hydrogen at a temperature of 400-650 ℃, a pressure of 2-4MPa and a molar ratio H2/feedstock of 3-6. The method can lead the yield of the benzene and the toluene to reach 75 percent.

CN200710043941.3 discloses a method for producing light aromatics and light alkanes from hydrocarbon raw materials, which comprises the steps of reacting the hydrocarbon raw materials with the boiling point of 30-250 ℃ in the presence of a Pt or Pd-containing zeolite catalyst, carrying out hydrodealkylation on heavy aromatics in the hydrocarbon raw materials and carrying out transalkylation reaction with the light aromatics, carrying out isomerization reaction on the light aromatics to convert the light aromatics into components rich in BTX (B is benzene, T is toluene and X is xylene) light aromatics, carrying out hydrocracking reaction on non-aromatics to generate light alkanes, separating liquid phase products into benzene, toluene, xylene and C9+ aromatics respectively according to different boiling points in a distillation tower, and separating the light alkanes from gas phase products. The method solves the technical problems that the traditional separation process of the hydrocarbon raw materials needs solvent extraction, the process is complex, the cost is high, and the heavy aromatic hydrocarbon and the non-aromatic hydrocarbon after separation have low utilization value.

CN200810043966.8 discloses a method for hydrocracking and producing more benzene and xylene by using pyrolysis gasoline. The method comprises the steps of reacting a C7+ pyrolysis gasoline raw material in the presence of a catalyst, carrying out hydrodealkylation on heavy aromatic hydrocarbons and carrying out transalkylation with light aromatic hydrocarbons, carrying out isomerization reaction on the light aromatic hydrocarbons to convert the light aromatic hydrocarbons into components rich in BTX light aromatic hydrocarbons, and separating liquid-phase products into benzene, toluene, xylene and C9+ fractions according to different boiling points, wherein the toluene and the C9+ fractions can be returned as feed materials to be continuously treated, and the light alkanes can be separated from gas-phase products. The method solves the problems that only BTX (B is benzene, T is toluene and X is xylene) aromatic hydrocarbon is simply separated in the traditional process of pyrolysis gasoline, a light aromatic hydrocarbon product contains a large amount of toluene, and the utilization value of the separated heavy aromatic hydrocarbon and non-aromatic hydrocarbon is low.

CN101362669A discloses a catalytic conversion method for preparing ethylene, propylene and aromatic hydrocarbon, which is characterized in that hydrocarbon raw materials with different cracking performances are contacted with a catalytic cracking catalyst, cracking reaction is carried out in a fluidized bed reactor, a spent catalyst and reaction oil gas are separated, the spent catalyst is regenerated and then returns to the reactor, the reaction oil gas is separated and separated to obtain target products, namely low-carbon olefin and aromatic hydrocarbon, wherein 160-260 ℃ fractions are used as circulating materials to return to the catalytic cracking, and ethane, propane and butane enter steam cracking to further produce ethylene and propylene. The method produces low-carbon olefins such as ethylene, propylene and the like from heavy raw materials to the maximum extent, the yield of the ethylene and the propylene is over 20 percent by weight, and aromatic hydrocarbons such as toluene, xylene and the like are co-produced.

The existing heavy aromatic hydrocarbon conversion technology mostly adopts a fixed bed hydrogenation dealkylation method, and has the disadvantages of harsh reaction conditions, complex operation and high catalyst requirement.

Disclosure of Invention

The invention aims to provide a method and a system for treating catalytic pyrolysis gasoline, which can efficiently convert the catalytic pyrolysis gasoline into low-carbon olefin and light aromatic hydrocarbon and realize long-period stable operation.

In order to achieve the above object, a first aspect of the present invention provides a method for treating catalytically cracked gasoline, the method comprising:

fractionating catalytically cracked gasoline and/or catalytically cracked oil gas from the catalytic cracking reaction unit to obtain light gasoline, heavy gasoline and optional other products;

aromatic extraction is carried out on the heavy gasoline to obtain benzene, toluene, xylene, C9+ aromatic hydrocarbon and aromatic raffinate oil;

enabling toluene and the C9+ aromatic hydrocarbon to enter a fluidized reactor to contact with a second catalyst and carrying out dealkylation and transalkylation coupling reaction under the hydrogen condition to obtain a dealkylated liquid product and a second spent catalyst; and mixing the dealkylation liquid product with the heavy gasoline, and then extracting the aromatic hydrocarbon.

The second aspect of the invention provides a process for producing light olefins and light aromatics in a high yield, which comprises the steps of enabling raw oil to contact a first catalyst in a catalytic cracking reactor to carry out catalytic cracking reaction to obtain catalytic cracking reaction oil gas, and treating the catalytic cracking reaction oil gas by adopting the method of the first aspect of the invention.

The third aspect of the invention provides a system for treating catalytically cracked gasoline, comprising a catalytically cracked gasoline inlet, a separation unit, an aromatic extraction unit and a dealkylation and transalkylation coupling reaction unit;

the separation unit comprises separation equipment, and the separation equipment is provided with a first oil-gas inlet, a light gasoline outlet, a heavy gasoline outlet and optional other product outlets; the first oil gas inlet is communicated with the catalytic pyrolysis gasoline inlet; the light gasoline outlet is optionally used for communicating with the inlet of the catalytic cracking reactor;

the aromatic hydrocarbon extraction unit comprises aromatic hydrocarbon extraction and separation equipment, and the aromatic hydrocarbon extraction and separation equipment is provided with a second oil gas inlet, a benzene outlet, a toluene outlet, a xylene outlet, a C9+ aromatic hydrocarbon outlet and an aromatic hydrocarbon raffinate oil outlet; the second oil-gas inlet is communicated with the heavy gasoline outlet of the separation unit; the aromatic raffinate oil outlet is optionally used for communicating with an inlet of a catalytic cracking reactor;

the dealkylation and transalkylation coupling reaction unit comprises a fluidization reactor, the fluidization reactor is provided with a third oil gas inlet and a dealkylation oil gas outlet, the third oil gas inlet is respectively communicated with the toluene outlet and the C9+ aromatic hydrocarbon outlet, and the dealkylation oil gas outlet is communicated with the second oil gas inlet of the aromatic hydrocarbon extraction unit.

The fourth aspect of the invention provides a device for producing light olefins and light aromatics in a high yield, which comprises a catalytic cracking reaction unit and the system of the third aspect of the invention, wherein a reaction oil gas outlet of the catalytic cracking reaction unit is communicated with a catalytic cracking reaction oil gas inlet of the system, a raw material inlet of the catalytic cracking reaction unit is communicated with a light gasoline outlet, and a raw material inlet of the catalytic cracking reaction unit is communicated with an aromatic raffinate oil outlet.

The method and the system provided by the invention adopt a fluidized bed reaction system to carry out hydrodealkylation treatment on heavy aromatic hydrocarbons in catalytic pyrolysis gasoline, can efficiently convert the catalytic pyrolysis gasoline into benzene and xylene, improve the yield of light aromatic hydrocarbons, have the advantages of continuous reaction and continuous regeneration, and good heat and mass transfer, and solve the problems of high content of heavy aromatic hydrocarbons in the pyrolysis gasoline of a catalytic pyrolysis device and difficult utilization.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a process flow diagram of one embodiment of the process for the production of light olefins and light aromatics in accordance with the present invention;

FIG. 2 is a schematic view of a catalytic cracking reaction unit of one embodiment of the system for treating catalytically cracked gasoline of the present invention;

fig. 3 is a schematic view of a second catalyst regenerator of an embodiment of the system for treating catalytically cracked gasoline of the present invention.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The invention provides a method for treating catalytic pyrolysis gasoline, which comprises the following steps:

fractionating catalytically cracked gasoline and/or catalytically cracked oil gas from the catalytic cracking reaction unit to obtain light gasoline, heavy gasoline and optional other products;

aromatic extraction is carried out on the heavy gasoline to obtain benzene, toluene, xylene, C9+ aromatic hydrocarbon and aromatic raffinate oil;

enabling toluene and the C9+ aromatic hydrocarbon to enter a fluidized reactor to contact with a second catalyst and carrying out dealkylation and transalkylation coupling reaction under the hydrogen condition to obtain a dealkylated liquid product and a second spent catalyst; and mixing the dealkylation liquid product with the heavy gasoline, and then extracting the aromatic hydrocarbon.

The method provided by the invention can efficiently convert catalytic cracking reaction oil gas and/or catalytic cracking gasoline into light aromatic hydrocarbon, improves the yield of the dimethylbenzene, can continuously react and continuously regenerate, is easy to maintain the stable property of the catalyst, has low device investment, and ensures long-period stable operation.

According to the invention, the catalytic pyrolysis gasoline is from a catalytic pyrolysis reaction unit and can be a component obtained by separating reaction oil gas generated by catalytic pyrolysis reaction. In the method of the present invention, the catalytically cracked gasoline to be treated may be fed alone as the raw material or in the form of catalytically cracked reaction oil gas containing catalytically cracked gasoline.

The apparatus and operating conditions for fractionating catalytically cracked gasoline and/or catalytically cracked reaction hydrocarbons according to the present invention are not particularly limited, and the apparatus for fractionating may be, for example, a fractionating tower, a flash drum, and the conditions for fractionating may be conventional in the art.

Preferably, the condition for carrying out fractionation can be that the initial boiling point of the light gasoline is 20-40 ℃, and the final boiling point is 80-100 ℃; the initial boiling point of the heavy gasoline is 80-100 ℃, and the final boiling point is 200-250 ℃. Other products can comprise low-carbon olefin, aromatic hydrocarbon above C12 and non-aromatic hydrocarbon components, wherein the low-carbon olefin mainly contains olefin with 2-4 carbon atoms.

According to the present invention, the light gasoline obtained by fractionation contains olefins with carbon atoms of 5 to 8, and in order to further improve the yield of the low carbon olefins, in a specific embodiment, as shown in fig. 1, the light gasoline obtained by fractionation may be returned to a catalytic cracking reaction unit to continue the catalytic cracking reaction, the catalytic cracking reactor may include a catalytic cracking reactor, the reactor may include a riser reactor and a fluidized bed reactor, and the position of the light gasoline returned to the catalytic cracking reactor is not limited, and the light gasoline may be returned to the riser reactor or the fluidized bed reactor.

According to the present invention, the heavy gasoline obtained by fractionation mainly contains BTX aromatic hydrocarbons, heavy aromatic hydrocarbons with a carbon number of above 9 and non-aromatic components, the heavy gasoline fraction can be subjected to aromatic extraction to further separate light aromatic hydrocarbon products such as benzene, toluene, xylene, etc., and simultaneously separate C9+ aromatic hydrocarbons, the apparatus and reaction conditions for aromatic extraction are not particularly limited, the apparatus for aromatic extraction includes, for example, an extraction column, a solvent recovery column and an aromatic separation column, the extraction agent can be conventional in the art, for example, sulfolane, tetraethylene glycol ether, diethylene glycol ether, N-methylpyrrolidone, and the types and operating conditions of the extraction column, the solvent recovery column and the aromatic separation column can be conventional in the art, and will not be described herein again.

According to the invention, the aromatic raffinate oil obtained by aromatic extraction contains non-aromatic components, and in order to further improve the yield of the low-carbon olefin, in a specific implementation mode, the aromatic raffinate oil can be returned to a catalytic cracking reactor for continuous catalytic cracking reaction.

According to the present invention, in order to produce xylene in high yield, in one embodiment, the C9+ aromatic hydrocarbon extracted from aromatic hydrocarbon and toluene can be fed into a fluidized reactor and contacted with a second catalyst under the hydrogen conditionDealkylation and transalkylation coupling reaction are carried out, C9+ aromatic hydrocarbon is further cracked and dealkylated, C9+ aromatic hydrocarbon and toluene are subjected to transalkylation reaction, the generated dealkylation product can be continuously subjected to gas-liquid separation to obtain dealkylation liquid product and hydrogen, the dealkylation liquid product rich in light aromatic hydrocarbon can be returned to the aromatic hydrocarbon extraction step to be mixed with heavy gasoline and then subjected to aromatic hydrocarbon extraction, so that light aromatic hydrocarbon products such as benzene, xylene and the like can be separated. The conditions for the hydrodealkylation and transalkylation coupling reaction of the C9+ aromatic hydrocarbon and the toluene in the fluidized reactor can be changed within a large range, in one embodiment, the reaction temperature can be 250-710 ℃, preferably 330-570 ℃, more preferably 340-540 ℃, the pressure can be 0-5.8 MPa, preferably 0.1-4.6 MPa, more preferably 1.2-3.8 MPa, and the weight hourly space velocity can be 0.2-6 h^-1Preferably 0.5 to 5.5 hours^-1More preferably 1.2 to 4 hours^-1The hydrogen/hydrocarbon molar ratio may be 1 to 15, preferably 2 to 12, and more preferably 4 to 8. The mode of feeding the C9+ aromatic hydrocarbons and the toluene into the fluidized reactor is not particularly required, and mixed feeding or layered feeding can be performed.

According to the present invention, the second catalyst for dealkylation and transalkylation coupling reaction may include a carrier and an active metal component supported on the carrier, and the composition and content of the second catalyst may vary in a wide range, and preferably, the content of the carrier in the second catalyst may be 50 to 99.99 wt%, preferably 55 to 85 wt%, based on the total weight of the second catalyst; the content of the active metal component may be 0.01 to 50% by weight, preferably 0.01 to 45% by weight.

The active metal component is preferably one or a combination of more than two of rare earth metals and transition metals, such as one or more of Fe, Ni, Pt, Pd, Co and Mo, preferably Ni, Pt and Pd.

The composition and amount of the support may also vary widely, and in a preferred embodiment, the support may contain 1 to 60 wt% zeolite, 5 to 99 wt% inorganic oxide, and 0 to 70 wt% clay, based on the dry weight of the support; more preferably, the carrier may contain 10 to 50 wt% of zeolite, 10 to 90 wt% of inorganic oxide and 1 to 60 wt% of clay. Further, the zeolite may comprise a medium pore zeolite and/or a large pore zeolite, preferably selected from medium pore zeolite and optionally large pore zeolite, preferably the weight of the medium pore zeolite is 50 to 100 wt% of the total weight of the zeolite, more preferably the weight of the medium pore zeolite is 70 to 90 wt% of the total weight of the zeolite; the large-pore zeolite accounts for 0-50 wt% of the total weight of the zeolite, and preferably the large-pore zeolite accounts for 10-30 wt% of the total weight of the zeolite.

In the support of the second catalyst according to the present invention, the medium-and large-pore zeolites may be of the type conventional in the art, for example ZSM zeolites and/or ZRP zeolites, the large-pore zeolites being preferably selected from one or more of beta zeolites, rare earth Y zeolites, rare earth hydrogen Y zeolites, ultrastable Y zeolites and high-silicon Y zeolites; in the carrier of the second catalyst, the inorganic oxide and the clay may each be of a kind conventional in the art, and the inorganic oxide may be at least one of silica, alumina, zirconia, titania and amorphous silica-alumina, preferably silica and/or alumina; the clay may preferably be selected from at least one of kaolin, montmorillonite, diatomaceous earth, attapulgite, sepiolite, halloysite, hydrotalcite, bentonite and rectorite, preferably kaolin and/or halloysite.

According to the present invention, the second catalyst for the hydrodealkylation reaction may be prepared by a method conventional in the art, for example, by supporting the active metal component on the above-mentioned carrier by a pore saturation impregnation method.

The second spent catalyst may be separated from the dealkylation and transalkylation reaction product in accordance with the present invention by means of cyclones, which are well known to those skilled in the art, or by means of filters, which are well known to those skilled in the art. The separated second spent catalyst can be sent to a second catalyst regenerator for regeneration and then recycled. The second catalyst regenerator may be of a type conventional in the art, and in one embodiment, the second spent catalyst may be introduced into a fluidized bed regenerator for regeneration and the resulting second regenerated catalyst recycled to the fluidized reactor. The regeneration of the spent catalyst is well known to those skilled in the art, all or at least part of the second catalyst can come from the second regenerated catalyst, during the regeneration process, an oxygen-containing gas is generally introduced from the bottom of the regenerator, the oxygen-containing gas can be air, for example, and after being introduced into the regenerator, the spent catalyst is contacted with oxygen for coke burning regeneration, the flue gas generated after the catalyst is burned and regenerated is subjected to gas-solid separation at the upper part of the regenerator, and the flue gas enters a subsequent energy recovery system. According to the property of active metal component of catalyst it can increase the regeneration process of catalyst, such as reduction and sulfurization.

In order to avoid contact between the hydrogen-containing gas stream and the oxygen-containing gas stream during catalyst regeneration and improve plant safety, in one embodiment, as shown in fig. 2, the fluidized bed regenerator may comprise a lock hopper, and the method of regeneration may comprise: and (3) enabling the second spent catalyst to enter the fluidized bed regenerator for regeneration through a lock hopper, and recycling the second regenerated catalyst to the fluidized reactor through the lock hopper. In this embodiment, the lock hopper allows for safe and efficient transfer of the second catalyst from the high pressure hydrocarbon or hydrogen environment of the reactor to the low pressure oxygen environment of the regenerator, and from the low pressure oxygen environment of the regenerator to the high pressure hydrocarbon or hydrogen environment of the reactor. By using the lock hopper, the reducing atmosphere (hydrogen atmosphere) of the reactor and the regenerated second catalyst feeding tank can be well isolated from the oxygen-containing atmosphere of the regenerator for coke burning regeneration, the safety of the process method is ensured, the operating pressure of the reactor and the regenerator can be flexibly regulated and controlled, and particularly the operating pressure of the reactor can be increased under the condition of not increasing the operating pressure of the regenerator, so that the treatment capacity of the device is increased. The lock hopper of the present invention is a device that allows the same material stream to be switched between different atmospheres (e.g., oxidizing and reducing atmospheres) and/or between different pressure environments (e.g., from high to low pressure, or vice versa), the construction and operation of which are well known to those skilled in the relevant art.

In a further embodiment, as shown in fig. 3, the fluidized bed regenerator may further comprise a reactor receiver 25, a regenerator receiver 28, a regeneration feed tank 30, and an optional reducer 29, and the second spent catalyst withdrawn from the fluidized bed reactor may be transferred to the reactor receiver 25, then transferred to the regeneration feed tank 30 through a lock hopper 26, then transferred from the regeneration feed tank 30 to the fluidized bed regenerator 27, and subjected to a coke-burning regeneration in the regenerator under an oxygen-containing atmosphere to obtain a second regenerated catalyst; the second regenerated catalyst is continuously withdrawn from the fluidized bed regenerator 27, passed through the regenerator receiver 28, and introduced into the reducer 29 for reduction, and returned to the fluidized bed reactor 23 for recycling.

In the method provided by the present invention, the fluidized reactor is a reactor which makes solid catalyst particles in a suspended motion state by using a reaction material gas and performs a gas-solid phase reaction process, and the type of the fluidized reactor is, for example, a dilute phase transport bed reactor, a fluidized bed reactor, a composite reactor composed of a dilute phase transport bed reactor and a fluidized bed reactor, a composite reactor composed of two or more dilute phase transport bed reactors, or a composite reactor composed of two or more fluidized bed reactors; wherein the dilute phase transport bed reactor is, for example, a riser reactor; the fluidized bed reactor is, for example, a bubbling bed reactor, a turbulent bed reactor or a fast bed reactor. In a preferred embodiment, the fluidized reactor according to the invention is preferably a fluidized bed reactor, which may comprise an upper expanded diameter section, in which a cyclone or a catalyst filter may be arranged for recovering catalyst entrained by the gas. In the case of a fluidized bed reactor or a riser reactor, the feeding and operation methods are the same as those of the conventional fluidized bed reactor or riser reactor in the prior art, and the present invention is not limited thereto.

The second aspect of the invention provides a process for producing light olefins and light aromatics in a high yield, which comprises the steps of enabling raw oil to contact a first catalyst in a catalytic cracking reactor to carry out catalytic cracking reaction to obtain catalytic cracking reaction oil gas containing catalytic cracking gasoline, and treating the catalytic cracking reaction oil gas by adopting the method of the first aspect of the invention.

According to the present invention, the catalytic cracking reactor may be of a kind conventional in the art, and in one embodiment, the catalytic cracking reactor includes a fluidized bed reactor and a riser reactor disposed one above another. In the embodiment of returning the light gasoline to the catalytic cracking reaction unit, the returning position of the light gasoline can be a fluidized bed reactor or a riser reactor. In embodiments where the aromatic raffinate is returned to the catalytic cracking unit, the return location for the aromatic raffinate may be a fluidized bed reactor or a riser reactor.

According to the present invention, the type of the feedstock oil is not particularly limited, and is, for example, at least one of gasoline, diesel oil, vacuum wax oil, atmospheric wax oil, coker wax oil, deasphalted oil, vacuum residue, atmospheric residue, raffinate oil, and low-grade recycle oil, coal liquefied oil, oil sand oil, and shale oil.

According to the present invention, the conditions of the catalytic cracking reaction may vary over a wide range, and preferably, the reaction conditions of the riser reactor may include: the reaction temperature is 550-720 ℃, the reaction time is 1-10 seconds, the reaction pressure is 130-450kPa, the catalyst-oil ratio is 1-100: 1; the reaction conditions of the fluidized bed reactor may include: the reaction temperature is 530 ℃ and 730 ℃, and the reaction time is 1-20 seconds.

According to the present invention, the first catalyst used for the catalytic cracking reaction may be a conventional catalytic cracking catalyst, and in one embodiment, the first catalyst contains, based on the total weight of the catalyst: 1-60 wt% of zeolite, 5-99 wt% of inorganic oxide and 0-70 wt% of clay, wherein the zeolite can comprise medium-pore zeolite and/or large-pore zeolite, preferably selected from medium-pore zeolite and optional large-pore zeolite, the medium-pore zeolite accounts for 50-100 wt%, preferably 70-100 wt% of the total weight of the zeolite, and the large-pore zeolite accounts for 0-50 wt%, preferably 0-30 wt% of the total weight of the zeolite. The medium pore zeolite is ZSM zeolite and/or ZRP zeolite, and the large pore zeolite is selected from one or more of beta zeolite, rare earth Y-type zeolite, rare earth hydrogen Y-type zeolite, ultrastable Y and high silicon Y; the inorganic oxide may be at least one selected from the group consisting of silica, alumina, zirconia, titania and amorphous silica-alumina; the clay is at least one selected from kaolin, montmorillonite, diatomaceous earth, attapulgite, sepiolite, halloysite, hydrotalcite, bentonite and rectorite.

A third aspect of the present invention provides a system for treating catalytically cracked gasoline,

comprises a catalytic pyrolysis gasoline inlet, a separation unit, an aromatic extraction unit and a dealkylation and transalkylation coupling reaction unit;

the separation unit comprises separation equipment, and the separation equipment is provided with a first oil-gas inlet, a light gasoline outlet, a heavy gasoline outlet and optional other product outlets; the first oil gas inlet is communicated with the catalytic pyrolysis gasoline inlet;

the aromatic hydrocarbon extraction unit comprises aromatic hydrocarbon extraction and separation equipment, and the aromatic hydrocarbon extraction and separation equipment is provided with a second oil gas inlet, a benzene outlet, a toluene outlet, a xylene outlet, a C9+ aromatic hydrocarbon outlet and an aromatic hydrocarbon raffinate oil outlet; the second oil-gas inlet is communicated with the heavy gasoline outlet of the separation unit;

the dealkylation and transalkylation coupling reaction unit comprises a fluidization reactor, the fluidization reactor is provided with a third oil gas inlet and a dealkylation oil gas outlet, the third oil gas inlet is respectively communicated with the toluene outlet and the C9+ aromatic hydrocarbon outlet, and the dealkylation oil gas outlet is communicated with the second oil gas inlet of the aromatic hydrocarbon extraction unit.

According to the invention, the light gasoline outlet is optionally used for communicating with the inlet of the catalytic cracking reactor, so that the light gasoline returns to the catalytic cracking reactor for continuous reaction.

According to the invention, the aromatic raffinate outlet is optionally used for communicating with the inlet of the catalytic cracking reactor so as to return the aromatic raffinate to the catalytic cracking reactor for continuous reaction.

According to the present invention, a separation unit and separation equipment, which may be conventional in the art, such as a fractionator, are used to separate light gasoline, heavy gasoline, and optionally other products from the catalytically cracked gasoline.

According to the invention, an aromatic hydrocarbon extraction unit and an aromatic hydrocarbon extraction and separation device are used for separating BTX aromatic hydrocarbon in gasoline middle distillate obtained by the separation unit, the aromatic hydrocarbon extraction and separation device can be a conventional type in the field, in one embodiment, the aromatic hydrocarbon extraction and separation device can comprise an aromatic hydrocarbon extraction device, an aromatic hydrocarbon separation tower and a solvent recovery device, and the aromatic hydrocarbon extraction device is provided with a third oil gas inlet, a solvent inlet, an aromatic hydrocarbon-solvent mixed liquid outlet and an aromatic hydrocarbon raffinate oil outlet; the solvent recovery equipment is provided with an aromatic hydrocarbon-solvent mixed liquid inlet, an aromatic hydrocarbon outlet and a solvent outlet, and the aromatic hydrocarbon-solvent mixed liquid inlet is communicated with the aromatic hydrocarbon-solvent mixed liquid outlet of the aromatic hydrocarbon extraction equipment; the aromatic hydrocarbon separation tower is provided with a fourth oil gas inlet, the benzene outlet, the toluene outlet, the xylene outlet and the C9+ aromatic hydrocarbon outlet, and the fourth oil gas inlet is communicated with the aromatic hydrocarbon outlet of the solvent recovery equipment.

According to the invention, the dealkylation and transalkylation coupling reaction unit is used for carrying out transalkylation reaction on the C9+ heavy aromatic hydrocarbons obtained by aromatic hydrocarbon extraction and toluene and further carrying out cracking dealkylation reaction on the C9+ aromatic hydrocarbons, so that the C9+ aromatic hydrocarbons are converted into light aromatic hydrocarbons and xylene is enriched. The fluidized reactor for carrying out the dealkylation and transalkylation coupled reaction is not particularly limited, and may be of a type conventional in the art, such as a dilute phase transport bed reactor, a fluidized bed reactor, a composite reactor composed of a dilute phase transport bed reactor and a fluidized bed reactor, a composite reactor composed of two or more dilute phase transport bed reactors, or a composite reactor composed of two or more fluidized bed reactors; wherein the dilute phase transport bed reactor can be a riser reactor; the fluidized bed reactor can be a bubbling bed reactor, a turbulent bed reactor or a fast bed reactor, and is preferably a bubbling bed reactor; the fluidized reactor may be an upflow reactor or a downflow reactor.

The dealkylation and transalkylation coupled reaction unit may further comprise a second catalyst regenerator, which may be of a type conventional in the art, preferably a fluidized bed regenerator, for regenerating the second spent catalyst, and in a further embodiment, for preventing the oxygen-containing gas stream from contacting the hydrogen-containing gas stream during regeneration, preferably a fluidized bed regenerator with a lock hopper, to further enhance the safety of the system. In other embodiments of the present invention, the catalyst transfer between the second catalyst regenerator and the fluidized reactor of the dealkylation reaction unit may employ conventional regeneration ramps and spent ramps.

The fourth aspect of the invention provides a device for producing light olefins and light aromatics in a high yield, which comprises a catalytic cracking reaction unit and the system of the third aspect of the invention, wherein a reaction oil gas outlet of the catalytic cracking reaction unit is communicated with a catalytic cracking reaction oil gas inlet of the system.

In one embodiment, the light gasoline outlet is communicated with the raw material inlet of the catalytic cracking reaction unit, so that the light gasoline is returned to the catalytic cracking reaction unit for recycling, and the yield of the low-carbon olefin is increased.

In one embodiment, the aromatic raffinate oil outlet is communicated with the raw material inlet of the catalytic cracking reaction unit, so that the aromatic raffinate oil is returned to the catalytic cracking reaction unit for recycling, and the yield of the low-carbon olefin is increased.

In a preferred embodiment, the light gasoline outlet and the aromatic raffinate oil outlet are respectively communicated with the raw material inlet of the catalytic cracking reaction unit.

The catalytic cracking reaction unit may be of a type conventional in the art, and for example, includes a catalytic cracking reactor, and in one embodiment, the catalytic cracking reaction unit includes a fluidized bed reactor and a riser reactor arranged up and down, and further includes a first catalyst regenerator for regenerating the first catalyst, and the first catalyst regenerator may be of a type conventional in the art, and the present invention is not limited thereto.

In a preferred embodiment, as shown in FIG. 1, the catalytic cracking process of the present invention comprises:

as shown in fig. 1, a raw oil 5 enters a catalytic cracking reaction unit 1 to perform a catalytic cracking reaction, a reaction oil gas 6 enters a product separation unit to be separated to obtain a light gasoline 7, a heavy gasoline 8 and optional other products, the light gasoline 7 returns to the catalytic cracking reaction unit 1 to continue the reaction, the heavy gasoline 8 enters an aromatic extraction separation unit 3 to be separated to obtain an aromatic raffinate oil 14, benzene 9, toluene 10, xylene 11, C9+ aromatic hydrocarbon 12, the aromatic raffinate oil 14 returns to the catalytic cracking reaction unit 1 to continue the reaction, the C9+ aromatic hydrocarbon 12 and the toluene 10 enter a dealkylation and transalkylation coupling reaction unit 4 to perform a hydrodealkylation-transalkylation coupling reaction, and a light liquid product 13 and the heavy gasoline 8 are mixed and then return to the aromatic extraction separation unit 3 to be separated.

As shown in fig. 2, the raw oil 5 enters the riser reactor 15 from the raw oil nozzle 16, the mixture of the reaction oil gas and the first catalyst ascends along the riser to reach the fluidized bed reactor 19, the mixture of the light gasoline 7 and the raffinate oil 14 of the aromatic hydrocarbon enters the fluidized bed reactor from the light gasoline nozzle 17 for reaction, the mixture of the reaction oil agent is separated in the gas-solid separation device 18 to obtain the reaction oil gas 6, the first catalyst to be regenerated enters the first regenerator 20 for regeneration, and the first catalyst to be regenerated returns to the bottom of the riser reactor 15 for recycling after being degassed by the degassing tank 21.

As shown in FIG. 3, a mixture 22 of C9+ aromatics and toluene is fed with hydrogen into a fluidized bed hydrodealkylation-transalkylation coupling reactor 23, contacting with a second catalyst to perform hydrodealkylation-transalkylation coupling reaction, leading the reaction product into a gas-liquid separation tank 24 to perform gas-liquid separation to obtain a light liquid product 13 and hydrogen, leading the second spent catalyst out of a fluidized bed hydrodealkylation-transalkylation coupling reactor 23, leading the second spent catalyst into a lock hopper 26 through a reactor receiver 25, then into a regeneration feed tank 30, and then into a second regenerator 27 (fluidized bed regenerator), and is subjected to scorching regeneration in the regenerator under an oxygen-containing atmosphere, and the obtained regenerated second catalyst is led out to a regenerator receiver 28, enters a reducer 29 through a lock hopper 26 for reduction, and returns to the fluidized bed hydrodealkylation-transalkylation coupling reactor 23 for recycling.

The following examples further illustrate the invention but are not intended to limit the invention thereto.

The properties of feedstock A used in the examples and comparative examples are shown in tables 1 and 2, wherein feedstock A is vacuum distillate and feedstock B is catalytic pyrolysis gasoline.

The first catalyst C1 used in the catalytic cracking reaction unit is purchased from China petrochemical Changling catalyst division and has the brand number of DMMC-2;

catalyst C2 for the catalytic cracking unit of comparative example 4 was purchased from catalyst division, petrifaction, chang, china under the designation CDOS.

Preparation examples 1 to 3 are provided to illustrate the preparation methods of the catalysts H1, H2 and H3.

Preparation of example 1

C3 preparation method: mixing the alumina sol and kaolin, preparing the mixture into slurry with the solid content of 10-50 wt% by using decationized water, uniformly stirring, adjusting the pH value of the slurry to 1-4 by using inorganic salt such as hydrochloric acid, nitric acid, phosphoric acid or sulfuric acid, keeping the pH value, standing and aging at 20-80 ℃ for 0-2 hours, adding the alumina sol, stirring for 0.5-1.5 hours to form colloid, adding a ZSM-5 molecular sieve and a beta-type molecular sieve (produced by a Changling catalyst factory) to form catalyst slurry (with the solid content of 35 wt%), continuously stirring, and performing spray drying to prepare the microsphere catalyst, wherein the ZSM-5: beta: kaolin: aluminum sol 20: 20: 39: 21. the microspherical catalyst was then calcined at 500 ℃ for 1 hour, washed with ammonium sulfate (where ammonium sulfate: microspherical catalyst: water 0.5:1:10) at 60 ℃ to a sodium oxide content of less than 0.25 wt%, then rinsed with deionized water and filtered, and then dried at 110 ℃, i.e., support C3 of this example.

The catalyst H1 was prepared by loading 0.04 wt% Pd and 0.04 wt% Pt (based on the total weight of the catalyst) on C3 by pore saturation impregnation and calcining at 400 deg.C for 4 hours.

Preparation of example 2

The presulfurized catalyst H2 was prepared by pore saturation impregnation using C3 as the carrier, wherein the weight ratio of NiS was 10% (based on the total weight of the catalyst).

Preparation of example 3

C4 preparation method: mixing the alumina sol and kaolin, preparing the mixture into slurry with the solid content of 10-50 wt% by using decationized water, uniformly stirring, adjusting the pH value of the slurry to 1-4 by using inorganic salt such as hydrochloric acid, nitric acid, phosphoric acid or sulfuric acid, keeping the pH value, standing and aging at 20-80 ℃ for 0-2 hours, adding the alumina sol, stirring for 0.5-1.5 hours to form colloid, adding a beta-type molecular sieve (produced by a Changling catalyst factory) to form catalyst slurry (with the solid content of 35 wt%), wherein beta: kaolin: aluminum sol 40: 39: and 21, continuously stirring, and then performing spray drying to prepare the microsphere catalyst. The microspherical catalyst was then calcined at 500 ℃ for 1 hour, washed with ammonium sulfate (where ammonium sulfate: microspherical catalyst: water 0.5:1:10) at 60 ℃ to a sodium oxide content of less than 0.25 wt%, then rinsed with deionized water and filtered, and then dried at 110 ℃, i.e., support C4 of this example.

The catalyst H3 was prepared by loading 0.04% Pd and 0.04% Pt (based on the total weight of the catalyst) on C4 by pore saturation impregnation and calcining at 400 ℃ for 4 hours.

Examples 1 to 7

Illustrating the method for treating catalytic pyrolysis gasoline of the present invention.

The tests were carried out according to the procedures shown in FIGS. 1 to 3, respectively, on a continuously regenerated, medium-sized fluidized bed apparatus, with a catalytic cracking unit catalyst C1, raw materials A used in examples 1 to 6, and raw material B used in example 7. The relevant operating conditions and products are listed in table 3.

Comparative example 1

The experiment was carried out according to the method of example 1, except that the heavy gasoline directly enters the extraction product separation unit without undergoing the distillate cut and the hydrodealkylation-transalkylation coupling reaction, and is separated to obtain the aromatic raffinate oil, benzene, toluene, xylene and C9+ aromatic hydrocarbons, wherein the light gasoline returns to the catalytic cracking reaction unit, and the aromatic raffinate oil does not return to the catalytic cracking reaction unit for reaction. The relevant operating conditions and products are listed in table 4.

Comparative example 2

The experiment was carried out according to the method of example 1, except that the product of the catalytic cracking unit was not subjected to hydrodealkylation reaction, but only directly separated to obtain low-carbon olefins, BTX, light gasoline, heavy gasoline, aromatic raffinate oil, etc., and the light gasoline and aromatic raffinate oil were not returned to the catalytic cracking reaction unit for reaction. The relevant operating conditions and products are listed in table 4.

Comparative example 3

An experiment was conducted in accordance with the method of example 1, except that the reactor of the dealkylation and transalkylation coupled reaction unit was a fixed bed reactor and the catalyst was regenerated discontinuously. The relevant operating conditions and products are listed in table 4.

Comparative example 4

A test was conducted in accordance with the procedure of example 1, except that the dealkylation and transalkylation reaction unit catalyst employed was a conventional catalytic cracking catalyst C2, and the reaction was conducted in the absence of hydrogen. The relevant operating conditions and products are listed in table 4.

Comparative example 5

An experiment was conducted in accordance with the procedure of example 1, except that the separated toluene was not returned to the hydrodealkylation-transalkylation coupled reactor reaction. The relevant operating conditions and products are listed in table 4.

TABLE 1 Properties of the raw materials

Heavy oil feedstock name	A
		Density (20 deg.C), kg/m3	912.1
Carbon residue, by weight%	3.14
		S, wt.%	0.39
N, weight%	0.13
		C, weight%	86.95
H, weight%	12.69
		Metal content, ppm
Ni	3.1
		V	3.2
Fe	0.2
		Four components, by weight%
Saturated hydrocarbons	54.7
		Aromatic hydrocarbons	33.5
Glue	11.6
		Asphaltenes	0.2

TABLE 2

TABLE 3

TABLE 4

As can be seen from the data of the examples and the comparative examples, the method for treating catalytic pyrolysis gasoline of the present invention can reduce the content of heavy aromatics of C9 or more and increase the content of BTX light aromatics. The catalytic cracking process adopts a fluidized bed reaction system to carry out light treatment on the heavy fraction of the gasoline, can effectively convert heavy aromatics in a cracking product into light aromatics, improves the BTX aromatic content, reduces the heavy aromatic content above C9, and produces more xylene. The method has the advantages of flexible operation, high elasticity, easy regeneration of the catalyst, uniform mass and heat transfer and capability of ensuring long-period stable operation.

The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.