Integrated process and system for generating paraxylene

Abstract

The integrated process for producing paraxylene involves catalytically reforming a naphtha feed stream to form a reformed oil stream; this reformed oil stream is then converted into a C1-C7 hydrocarbon stream and C 8+ Steps to separate into hydrocarbon streams; steps to expose the C1-C7 hydrocarbon streams to a first solvent in a solvent extraction unit to form non-aromatic hydrocarbon streams and C6-C7 aromatic compound streams; steps to separate the C6-C7 aromatic compound streams into at least a toluene feed stream; C 8+ Hydrocarbon flow C 9+ Steps to separate the hydrocarbon stream and the xylene stream; steps to separate the xylene stream in a p-xylene separation unit to form a para-xylene stream and a xylene isomer stream; steps to isomerize the xylene isomer stream to produce a para-xylene-rich stream; and steps to separate the toluene feed stream and C in a hybrid dealkylation / transalkylation unit. 9+ The process may include upgrading the hydrocarbon stream with a hydrogen stream and a hybrid transalkylation / dealkylation catalyst to produce a product stream containing paraxylene.

Description

Description of Related Applications

[0001] This application claims priority to U.S. Patent Application No. 18 / 183,299, filed on March 14, 2023, the entire content of which is incorporated herein by reference.

Technical Field

[0002] Embodiments of the present disclosure broadly relate to the refining and upgrading of hydrocarbon oils, and more particularly to an integrated process and system for upgrading a naphtha stream to paraxylene.

Background Art

[0003] Aromatic compounds such as benzene, toluene, and xylene (BTX) are fundamental intermediates for many petrochemical industries. A particularly desirable intermediate is paraxylene, which is a xylene isomer in the group of 1,2-dimethylbenzene (orthoxylene or o-xylene), 1,3-dimethylbenzene (metaxylene or m-xylene), or 1,4-dimethylbenzene (paraxylene or p-xylene). Paraxylene may be used, inter alia, as a raw material in the synthesis of commercially available plastics for clothing fibers, storage containers for liquids and foods, and thermoforming for manufacturing. Therefore, a method for converting all hydrocarbon feeds to paraxylene is desirable.

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a refining process for producing BTX, a naphtha feed is first sent to a catalytic reformer. The catalytic reformer reforms the naphtha stream into a reformed oil stream rich in aromatic compounds. The reformed oil stream is then typically separated into a light (carbon content less than 8) stream and a heavy (carbon content greater than 7) stream.

[0005] However, with a carbon content greater than 9 (C 10+Aromatic compounds are typically purged from heavy flows and will not be utilized in either of these flows, as they are considered petroleum coke precursors (potentially deactivating catalysts and accumulating as unconverted fractions in recirculated flows). Hydrocarbon flows, and some naphtha flows, utilize these C 10+ Since it will contain a large proportion of fractions, a considerable amount of paraxylene and other xylene isomers will not be fully utilized within existing processes. Therefore, to utilize the entire naphtha flow and maximize the yield of paraxylene, C in the naphtha flow is used. 10+ A method for converting the fractions is preferable. [Means for solving the problem]

[0006] As a result, an integrated process and system for generating paraxylene from naphtha feedstreams while providing the aforementioned benefits is described herein. For details, see C above. 10+ C such as fractionation 9+ The fractions can be converted using hybrid transalkylation / dealkylation units and catalysts to increase the yields of xylene and paraxylene. In this way, all of the heavy fractions in the naphtha feedstream can be converted to xylene, particularly paraxylene.

[0007] According to one embodiment of this specification, the integrated process for producing paraxylene involves catalytically reforming a naphtha feed stream to form a reformed oil stream; and this reformed oil stream is converted into a C1-C7 hydrocarbon stream and C 8+ Steps to separate into hydrocarbon streams; steps to expose the C1-C7 hydrocarbon streams to a first solvent in a solvent extraction unit to form non-aromatic hydrocarbon streams and C6-C7 aromatic compound streams; steps to separate the C6-C7 aromatic compound streams into at least a toluene feed stream; C 8+ Hydrocarbon flow C 9+A step of separating into a hydrocarbon stream and a xylene stream containing orthoxylene, metaxylene, and paraxylene; a step of separating the xylene stream in a p-xylene separation unit to form a paraxylene stream and a xylene isomer stream containing orthoxylene and metaxylene; a step of isomerizing the xylene isomer stream with an isomerization catalyst to generate a stream rich in paraxylene; and a toluene feed stream and C 9+ A hydrocarbon stream may be upgraded with a hydrogen stream and a hybrid transalkylation / dealkylation catalyst to generate a product stream containing paraxylene, and the mass ratio of the toluene feed stream to C 9+ The hydrocarbon stream is from 0.3 to 3.

[0008] According to another embodiment herein, an integrated system for producing paraxylene includes a catalytic reformer containing a reforming catalyst; a first separator fluidly connected downstream of the catalytic reformer; a solvent extraction unit containing a first solvent, the solvent extraction unit being fluidly connected downstream of the first separator; a toluene separation unit fluidly connected downstream of the solvent extraction unit; a xylene separation unit fluidly connected downstream of the first separator; a hybrid transalkylation / dealkylation unit containing a hybrid transalkylation / dealkylation catalyst, the hybrid transalkylation / dealkylation unit being fluidly connected downstream of the toluene separation unit and the xylene separation unit; a p-xylene separation unit fluidly connected downstream of the xylene separation unit; and a xylene isomerization unit containing an isomerization catalyst, the xylene isomerization unit being fluidly connected downstream and upstream of the p-xylene separation unit.

[0009] Additional features and advantages of the embodiments described herein are set forth in the following detailed description, some of which will be readily apparent to those skilled in the art from that description, or will be recognized by practicing the described embodiments, which include the detailed description and the claims provided below. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The following detailed description of special embodiments of this disclosure will be best understood when read in conjunction with the following drawings. [Figure 1] Process diagram illustrating the process according to the embodiments described herein. [Figure 2] Another process diagram illustrating the process described in the embodiments described herein. [Figure 3] Figure showing the comparative results of two pilot plant experiments of the exemplary processes described in the embodiments described herein. [Modes for carrying out the invention]

[0011] Simplified schematic diagrams and descriptions of the relevant drawings may be used for illustrative purposes and do not include a number of valves, temperature sensors, electronic control devices, etc., that are well known to those skilled in the art of a particular chemical treatment operation. Furthermore, ancillary components that are usually included in a typical chemical treatment operation, such as intake ports, catalyst hoppers, and flue gas treatment systems, are not shown. Components associated with the hydrogenation treatment unit, such as extraction flow, spent catalyst discharge subsystem, and catalyst exchange subsystem, are also not shown. It should be understood that these components are included in the spirit and scope of the disclosed embodiments. However, operational components, such as those described in this disclosure, may be added to the embodiments described in this disclosure.

[0012] Furthermore, it should be noted that arrows in the drawings indicate process flows. However, these arrows may also equivalently indicate transfer lines that can transport process flows between two or more system components. Additionally, arrows connected to system components define inlets or outlets in each given system component. The direction of the arrows generally coincides with the primary direction of movement of the material in the flow contained within the physical transfer line indicated by the arrow. Furthermore, arrows that do not connect two or more system components represent product flows exiting the depicted system or system inlet flows entering the depicted system. Product flows may be further processed in an accompanying chemical processing system or commercialized as final products. System inlet flows may be flows transported from an accompanying chemical processing system or unprocessed raw material flows. Some arrows may represent outlets of system components, representing recirculated flows that are recycled back into the system. However, it should be understood that in some embodiments, any of the represented recirculated flows may be replaced by system inlet flows of the same material, and some of the recirculated flows may exit the system as products.

[0013] Furthermore, arrows in the diagram may schematically depict process steps that transport a flow from one system component to another. For example, an arrow pointing from one system component to another may represent "passing" the outflow from one system component to the other, which may include the contents of the process flow "leaving" or "removing" one system component and "introducing" the contents of its product flow into the other system component.

[0014] In embodiments shown in the relevant drawings, it should be understood that arrows between two system components may indicate that the flow is not processed between the two system components. In other embodiments, the flow indicated by the arrows may have substantially the same composition through transport between the two system components. Furthermore, it should be understood that in embodiments, the arrows may indicate that at least 75% by mass, at least 90% by mass, at least 95% by mass, at least 99% by mass, at least 99.9% by mass, or even 100% by mass of the flow is transported between the system components. Thus, in embodiments, not all of the flow indicated by the arrows is transported between system components, such as when a slip stream is present.

[0015] When two or more lines intersect in a schematic flowchart of the relevant drawings, it should be understood that the two or more process flows are “mixed” or “combined.” Mixing or combining may also include mixing by directly introducing both flows into a similar reactor, separation unit, or other system component. For example, if two flows are depicted as combining directly before entering a separation unit or reactor, it should be understood that in the embodiment, the flows can be equivalently introduced into the separation unit or reactor and mixed in the reactor. Alternatively, if two flows are depicted entering a system component independently, they may be mixed with each other before entering that system component in the embodiment.

[0016] Herein, we refer in detail to various embodiments of the present disclosure, some of which are shown in the accompanying drawings. Wherever possible, the same reference numerals are used to refer to the same or similar parts across the drawings.

[0017] Embodiments herein relate to integrated systems and processes for forming paraxylene from naphtha flows while providing the benefits described above.

[0018] As used here, "#" is a positive integer, "C # The term "hydrocarbon" is intended to describe all hydrocarbons that have # carbon atoms. Furthermore, "C #+ The term "hydrocarbon" is primarily intended to describe all hydrocarbon molecules that have # or more carbon atoms. Therefore, "C 8+ The term "hydrocarbon" is primarily intended to describe mixtures of hydrocarbons containing eight or more carbon atoms. Similarly, "C #- The term "hydrocarbon" is intended to describe all hydrocarbon molecules having # or fewer carbon atoms. Similarly, "C # ~C #’ The term "hydrocarbon" is primarily intended to describe mixtures of hydrocarbon molecules having between # and #' carbon atoms.

[0019] As used herein, “catalyst” refers to any substance that increases the rate of a particular chemical reaction. The catalysts described herein, but are not limited to, can be used to accelerate a variety of reactions, including but are not limited to, decomposition (including aromatic decomposition), demetallation, desulfurization, denitrification, methylation, disproportionation, dealkylation, dearylation, transalkylation, and isomerization. As used herein, “cracking” broadly refers to a chemical reaction in which carbon-carbon bonds are cleaved. For example, a molecule having carbon-carbon bonds may be broken into multiple molecules by the cleavage of one or more carbon-carbon bonds, or a compound containing a cyclic moiety, such as cycloalkanes, naphthalenes, or aromatic compounds, may be converted into a compound that does not contain a cyclic moiety or contains fewer cyclic moieties than before the decomposition.

[0020] As used herein, "catalytic reforming" refers to a conversion process in the petroleum refining and petrochemical industries. The reforming process generally catalytically converts low-octane naphtha distilled from crude oil into high-octane reformed oil containing aromatic compounds, including a large amount of BTX. Generally, there are four main types of reactions that occur during the reforming process: (1) dehydrogenation of naphthenes to aromatic compounds; (2) dehydrogenation and cyclization of paraffins to aromatic compounds; (3) isomerization; and (4) hydrocracking.

[0021] As used herein, the term “crude oil” is to be understood to mean petroleum, petroleum gas, or a mixture of petroleum and petroleum gas containing several impurities, such as sulfur-containing compounds, nitrogen-containing compounds, and metallic compounds, that have not undergone significant separation or reaction processes. Crude oil is distinguished from fractions of crude oil. As used herein, crude oil may be minimally processed crude oil having a total metal (nickel + vanadium) content of less than 5 parts per million by mass (ppmw) and a Conradson residual carbon content of less than 5% by mass to provide hydrocarbon oil raw materials. Such minimally processed material may be considered crude oil as described herein.

[0022] "Efffluent" broadly refers to the flow leaving a system component such as a separation unit, reactor, or reaction zone after a particular reaction or separation, and should generally be understood to have a different composition (at least proportionally) from the flow entering the separation unit, reactor, or reaction zone.

[0023] As used herein, the terms "hydrogen / feed ratio," "hydrogen to feed ratio," or "hydrogen to feed flow ratio" refer to a standard measure of the volumetric flow rate of hydrogen circulating through the reactor relative to the volume of feed. The hydrogen / feed ratio can be determined by comparing the flow rate of hydrogen entering the reactor with the flow rate of the feed flow.

[0024] As used here, the term "naphtha" refers to C5 to C 11This refers to a mixture of substances mainly containing hydrocarbons. The term "light naphtha" used here refers to a fraction of naphtha that mainly contains C5 to C6 hydrocarbons, but may also contain C7 hydrocarbons. As used here, the term "heavy naphtha" refers to a mixture of substances mainly containing C7 to C6 hydrocarbons. 11 It is a naphtha fraction mainly containing hydrocarbons.

[0025] As used herein, “reactor” refers to a vessel in which one or more chemical reactions can take place between one or more reactants in the presence of one or more catalysts, as may be required. For example, a reactor may include a batch reactor, a continuous stirred tank reactor (CSTR), or a tank or tubular reactor configured to operate as a tubular reactor. Exemplary reactors include packed bed reactors such as fixed bed reactors, and fluidized bed reactors. One or more “reaction zones” may be located within the reactor. As used herein, “reaction zone” refers to an area within the reactor in which a particular reaction takes place. For example, a packed bed reactor with multiple catalyst beds may have multiple reaction zones, each reaction zone being defined by an area of ​​each catalyst bed.

[0026] As used herein, any stream described as “rich” in several chemical species contains at least 50% by volume or mass of that chemical species, for example, 50% to 100%, or 50% to 99% (the remaining 1% including trace amounts of other chemical species).

[0027] As used herein, “separation unit” or “separator” refers to any separation device that separates one or more chemical substances mixed in a process stream from each other, at least partially. For example, a separation unit can selectively separate different chemical species, phases, or materials of different sizes from each other to form one or more chemical fractions. Examples of separation units include, without limitation, distillation columns, flash drums, knockout drums, knockout pots, centrifuges, cyclones, filters, traps, scrubbers, expansion devices, membranes, and solvent extractors. It should be understood that the separation processes described herein may not completely separate all of one chemical component from all of another. It should be understood that the separation processes described herein separate different chemical components from each other “at least partially,” and that separation may include only partial separation, even if not explicitly stated otherwise. As used herein, one or more chemical components can be “separated” from a process stream to form a new process stream. Generally, a process stream enters a separation unit and may be divided or separated into two or more process streams of a desired composition. Furthermore, in some separation processes, a "low-boiling fraction" (sometimes referred to as a "light fraction" or "light fraction stream") and a "high-boiling fraction" (sometimes referred to as a "heavy fraction," "heavy hydrocarbon fraction," or "heavy hydrocarbon fraction stream") may exit the separation unit, where, on average, the contents of the low-boiling fraction stream have lower boiling points than the high-boiling fraction stream. Other streams may fall between the low-boiling and high-boiling fractions, such as an "intermediate-boiling fraction."

[0028] As used throughout this disclosure, “zeolite” may refer to a microporous inorganic material having regular crystalline cavities and pathways of molecular size. Zeolites generally have a crystalline structure, as opposed to an amorphous structure, such as that observed in certain porous materials like amorphous silica. Zeolites generally have a microporous framework, which may be identified by its framework type. The microporous structure of zeolites (e.g., pore diameters from 0.3 nm to 2 nm) provides a large surface area and desirable size / shape selectivity, which would be advantageous for catalytic activity. Examples of zeolites described include aluminosilicates, titanosilicates, or pure silicates. In embodiments, the zeolites described may contain micropores (present in the microstructure of the zeolite) and may further contain mesopores. As used throughout this disclosure, micropores refer to pores in a structure having a diameter of 0.1 nm or more and 2 nm or less, and mesopores refer to pores in a structure having a diameter of more than 2 nm and 50 nm or less. Unless otherwise specified herein, the “pore diameter” of a material refers to the average pore diameter, but the material may further include micropores and / or mesopores having specific sizes that are not identical to its average pore diameter.

[0029] It should be further understood that a flow may be named in terms of its components, and the component of a named flow may be the main component of the flow (for example, including 50 mass percent (mass%), 70 mass%, 90 mass%, 95 mass%, 99 mass%, 99.5 mass%, and even 99.9 mass%, up to 100 mass%) of the flow content. It should also be understood that the components of a flow are disclosed when a flow containing those components is disclosed passing from one system component to another. As a non-limiting example, a “C2-C4 hydrocarbon flow” mentioned passing from a first system component to a second system component is equivalent to disclosing a “C2-C4 hydrocarbon” passing from a first system component to a second system component.

[0030] Referring first to Figure 1, an integrated system 100 for the conversion of naphtha raw materials is shown. As used herein, “raw materials” may also be used to refer to “feed material” or “feed stream.” The integrated system 100 may comprise a catalytic reformer 102, a first separator 104, a solvent extraction unit 106, a toluene separation unit 107, a xylene separation unit 110, a hybrid transalkylation / dealkylation unit 116, a p-xylene separation unit 118, and a xylene isomerization unit 120. The toluene separation unit 107 may further comprise a benzene column 108 together with a toluene column 109, both of which may be atmospheric distillation units, as will be described in more detail herein.

[0031] The first separator 104 is downstream of the catalytic reformer 102 and upstream of the solvent extraction unit 106, and may be fluid-connected to both the catalytic reformer 102 and the solvent extraction unit 106. The benzene column 108 (which may be considered a second separator 108) is downstream of the solvent extraction unit 106 and upstream of the toluene column 109, and may be fluid-connected to both the solvent extraction unit 106 and the toluene column 109. The toluene column 109 (which may be considered a third separator 109) may be fluid-connected upstream of the hybrid transalkylation / dealkylation unit 116. The xylene separation unit 110 (which may be considered a fourth separator 110) may be fluid-connected to the first separator 104, the hybrid transalkylation / dealkylation unit 116, and the p-xylene separation unit 118. The xylene separation unit 110 may be located downstream of the first separator 104 and upstream of the hybrid transalkylation / dealkylation unit 116 and the p-xylene separation unit 118.

[0032] The p-xylene separation unit 118 (sometimes considered a fifth separator) may be fluidly connected to the xylene separation unit 110 and the xylene isomerization unit 120. The p-xylene separation unit 118 may be downstream of the xylene separation unit 110 and upstream of the xylene isomerization unit 120. The xylene isomerization unit 120 may then also be upstream of the p-xylene separation unit 118, that is, the xylene isomerization unit 120 can recirculate its products back to the p-xylene separation unit 118.

[0033] Furthermore, referring to Figure 1, the catalytic reforming apparatus 102 can catalytically reform the naphtha supply flow 2 using a catalytic reforming catalyst to produce a reformed oil flow 4. The reformed oil flow 4 contains aromatic compounds, particularly C 6+ Or C6~C 12 Aromatic compounds may be abundant. As mentioned earlier, any stream described as "rich" in any particular chemical species contains at least 50% by volume or mass of that species, for example, 50% to 100%, or 50% to 99% (the remaining 1% consisting of trace amounts of other chemical species).

[0034] The catalytic reformer 102 can be operated at an operating temperature range of 450°C to 600°C. The catalytic reformer 102 can also be operated at an operating pressure range of 0.3 MPa to 7 MPa. This catalytic reformer has a lifespan of 0.1 hr. -1 from 5hr -1 It can also be operated at the liquid space velocity.

[0035] The catalytic reforming catalyst may contain a support and a noble metal, the support may include silica, alumina, or silica-alumina, and the noble metal may include platinum, ruthenium, or both. The reforming catalyst may also be chlorinated. The first separator 104 receives the reformed oil flow 4 and separates it with the C1-C7 hydrocarbon flow 6 and C 8+ It can be separated into hydrocarbon stream 8.

[0036] The naphtha feed stream 2 may contain light naphtha or heavy naphtha. The naphtha feed stream 2 may also contain one or more non-hydrocarbon components, such as one or more heavy metals, sulfur compounds, nitrogen compounds, inorganic components, or other non-hydrocarbon compounds. The naphtha feed stream 2 may also be hydrogenated naphtha, hydrogenated light naphtha, or hydrogenated heavy naphtha, and therefore at least some of the one or more non-hydrocarbon components may be removed from the naphtha feed stream 2.

[0037] The solvent extraction unit 106 may receive a C1-C7 hydrocarbon stream 6 together with the first solvent 5. The solvent extraction unit 106 can thereby expose the C1-C7 hydrocarbon stream 6 to the first solvent 5 to form a non-aromatic hydrocarbon stream 10 and a C6-C7 aromatic compound stream 12. The non-aromatic compound stream 10 may contain C1-C7 non-aromatic hydrocarbon gases and hydrogen. The C6-C7 aromatic compound stream 12 may contain toluene and benzene, and may be rich in toluene, benzene, or a combination thereof.

[0038] In the embodiment, the solvent extraction unit 106 may include one or more extraction distillation columns, one or more absorption columns, or a combination thereof. The first solvent 5 may include, but is not limited to, polar solvents such as sulfolane, n-methylpyrrolidone, dimethyl sulfoxide, n-formylmorpholine, polyglycol, or a combination thereof. The solvent extraction unit 106 can be operated at an operating temperature in the range of 160°C to 220°C. The solvent extraction unit 106 can also be operated at an operating pressure in the range of 0.5 MPa to 20 MPa.

[0039] The toluene separation unit 107, specifically the benzene column 108, can receive the aromatic compound stream 12, thereby separating the C6-C7 aromatic compound stream 12 into a benzene-rich stream 13 and a toluene-rich stream 14. The toluene column 109 can receive the toluene-rich stream 14 and form a toluene feed stream 15. The toluene separation unit 107 can also feed the toluene feed stream 15 to the hybrid transalkylation / dealkylation unit 116 through the toluene column 109, etc. The toluene feed stream 15 may also be mixed with an external toluene stream if the toluene in its system is not at a sufficient level for the desired transalkylation.

[0040] Furthermore, referring to Figure 1, the xylene separation unit 110 is C 8+ It can receive hydrocarbon flow 8 and then C 9+ The hydrocarbon stream 18 and xylene stream 20 can be separated. The xylene stream may contain orthoxylene, metaxylene, and paraxylene. The hybrid transalkylation / dealkylation unit 116 then processes C 9+ It can receive a hydrocarbon stream 18 and a toluene feed stream 15. The hybrid transalkylation / dealkylation unit 116 can then upgrade its combination of the two streams to a product stream 24 with a hydrogen stream 22, which may contain xylene.

[0041] Product flow 24 includes, but is not limited to, trimethylbenzene (TMB), methylethylbenzene (MEB), tetramethylbenzene, dimethylethylbenzene, and tetraethylbenzene, as well as unconverted C9 and C9. 10+ The product stream may also include hydrocarbon fractions and unconverted toluene fractions. In the embodiment, the product stream is toluene and C 9+This may also include aromatic fractions resulting from the disproportionation of hydrocarbon fractions. In one non-limiting example, toluene and trimethylbenzene can form benzene and tetramethylbenzene, respectively. Although not limited by theory, this could also include other C 9+ Among aromatic compound-toluene pairs, this is likely due to the equilibrium reaction of transalkylation between trimethylbenzene and toluene (where the chemical species involved are disproportionately, at least to some extent, when exposed to a hybrid transalkylation / dealkylation catalyst).

[0042] In addition, although not limited by theory, other C 9+ Among aromatic compound-toluene pairs, the efficiency of the transalkylation reaction that produces xylene from TMB and toluene will be affected by the volume ratio of these species entering the hybrid transalkylation / dealkylation unit 116, since the TMB / toluene transalkylation reaction is an equilibrium reaction as previously described. Therefore, C 9+ The ratio of the toluene supply stream 15 to the hydrocarbon stream 18 can be considered to be between 0.3 and 3 in the embodiments described herein. A ratio of less than 0.3 may result in insufficient toluene present in the hybrid transalkylation / dealkylation unit 116, thereby causing C 9+ In hybrid transalkylation / dealkylation unit 116, the less energy-efficient disproportionation reaction involving hydrocarbons will likely outperform the transalkylation reaction. At ratios greater than 3, the opposite may occur, with excess toluene undergoing the less energy-efficient toluene disproportionation reaction. While not theoretically limited, the transalkylation of TMB and toluene can be considered more energy-efficient because the reaction product is entirely xylene, rather than xylene and non-xylene aromatic compounds.

[0043] Hybrid transalkylation / dealkylation catalysts may contain a solid zeolite complex mixed with an alumina binder. The solid zeolite complex may have large-pore mordenite and intermediate-pore ZSM-5. The mass ratio of large-pore mordenite and intermediate-pore ZSM-5 in the solid zeolite complex may be 1:1 to 5:1. Furthermore, as used herein, "large-pore" is defined as a zeolite in which 12-membered rings form the zeolite framework. Furthermore, as used herein, "intermediate-pore" zeolite is defined as a zeolite in which 10-membered rings form the zeolite framework.

[0044] Furthermore, the hybrid transalkylation / dealkylation catalyst may have a mesostructure comprising at least one disordered intermediate phase and at least one ordered intermediate phase. The ordered intermediate phase may be a hexagonal intermediate phase, and the disordered intermediate phase may contain a hexagonal intermediate phase. As used herein, “ordered intermediate phase” may refer to a uniform arrangement of crystalline zeolite mesopores, where “mesopores” have an average pore diameter between 2 nanometers and 50 nanometers. As used herein, “disordered intermediate phase” means a non-uniform arrangement of pores, where the mesopores have an average pore diameter between 2 nanometers and 50 nanometers. The hybrid transalkylation / dealkylation catalyst may also contain an active metal. The active metal may be impregnated onto the hybrid transalkylation / dealkylation catalyst. The active metal may be selected from the group consisting of molybdenum, chromium, platinum, nickel, palladium, rhenium, or a combination thereof.

[0045] The hybrid transalkylation / dealkylation unit 116 can be operated at operating temperatures ranging from 300°C to 480°C. The hybrid transalkylation / dealkylation unit 116 can also be operated at operating pressures ranging from 1 MPa to 3 MPa. The hybrid transalkylation / dealkylation unit 116 has a lifespan of 0.1 hours. -1 from 10hr -1It can also be operated at liquid space velocity. The hybrid transalkylation / dealkylation unit 116 can also be operated with hydrogen pair supply flows 1 to 6 (flows 15 and 18).

[0046] Referring further to Figure 1, the system 100 may further include a sixth separator 122. The sixth separator 122 may be fluid-connected downstream of the hybrid transalkylation / dealkylation unit 116. The sixth separator 122 may also be fluid-connected upstream of the xylene separation unit 110, the benzene column 108, and the p-xylene separation unit 118. The sixth separator 122 may receive a product stream 24, which contains at least an additional non-aromatic hydrocarbon stream 10, an additional C6-C7 aromatic compound stream 12, an additional xylene stream 20, and unconverted C6-C7. 9+ It can be separated into hydrocarbon stream 26. Unconverted C 9+ The hydrocarbon stream 26 specifically consists of an unconverted C9 hydrocarbon fraction stream and an unconverted C 10+ It may contain hydrocarbon fractional flow. In this embodiment, the sixth separator 122 contains unconverted C 9+ Send the hydrocarbon flow 26, C 9+ It can be mixed with hydrocarbon flow 18. Therefore, the unconverted C 9+ The hydrocarbon stream 26 can then be recycled to be upgraded within the hybrid transalkylation / dealkylation unit 116 to form an additional product stream 24.

[0047] As mentioned earlier, in the purification process that produces several BTX, C 10+ Aromatic hydrocarbons are typically removed from the system and transferred to a fuel oil pool or similar location. One reason for doing so is C 10+ Aromatic hydrocarbons are not converted as efficiently as C9 aromatic compounds, and these fractions progressively accumulate in the feed during subsequent operations. 10+Aromatic hydrocarbons are known to potentially deactivate catalysts (due to poisoning or contamination, etc.), and this is known to C 10+ This becomes increasingly problematic as the proportion of feed containing aromatic hydrocarbons increases. However, as will be explained in more detail in the following examples, the hybrid transalkylation / dealkylation unit 116 and the hybrid transalkylation / dealkylation catalyst are C 10+ It exhibits an unexpected ability to convert hydrocarbon fractions, reducing the accumulation of such fractions in the hybrid transalkylation / dealkylation unit 116 over subsequent operations. Therefore, C 10+ The hydrocarbon fraction can be recycled to the hybrid transalkylation / dealkylation unit 116, thereby enabling the utilization of the entire hydrocarbon feedstock with the aim of producing BTX, particularly paraxylene.

[0048] While not limited by theory, it is thought that the unexpected capabilities of hybrid transalkylation / dealkylation catalysts are at least partly due to their partial dealkylation function. More specifically, when dealkylation function is included, C 10+ It functions to remove alkyl groups from heavy aromatic fractions such as aromatic compounds (diethylbenzene and / or tetramethylbenzene, methylpropylbenzene, trimethylethylbenzene, etc.), thereby forming light aromatic fractions such as TMB, xylene, and toluene. As mentioned earlier, these light aromatic fractions can efficiently undergo transalkylation reactions to form xylene in the toluene feed stream 15. The dealkylation function of the hybrid transalkylation / dealkylation catalyst is relatively low, but C 12+ It is also conceivable that alkyl groups that function as bridges for bicyclic or polycyclic aromatic compounds, such as aromatic fractions, can be removed.

[0049] Referring further to Figure 1, the p-xylene separation unit 118 can receive the xylene stream 20 and additional xylene streams 20. The p-xylene separation unit 118 can also be operated to separate the xylene stream 20 into a para-xylene stream 29 and a xylene isomer stream 30 by adsorption, crystallization, or a combination of both, as will be understood in the art. The xylene isomer stream 30 may contain m-xylene and o-xylene isomers. In the embodiment, the p-xylene separation unit 118 may include one or more adsorption columns, one or more crystallization columns, or a combination thereof.

[0050] The xylene isomerization unit 120 can receive the xylene isomer stream 30 and isomerize it with an isomerization catalyst to form a paraxylene-rich stream 31, which can be recirculated back to the p-xylene separation unit 118 for further extraction of the paraxylene stream 29 and the xylene isomer stream 30. The xylene isomerization unit 120 can be operated at an operating temperature in the range of 200°C to 540°C. The xylene isomerization unit 120 can also be operated at an operating pressure in the range of 1 MPa to 5 MPa. The xylene isomerization unit 120 has a lifespan of 0.1 hr -1 from 20hr -1 It can also operate at liquid space velocity.

[0051] The isomerization catalyst may include a mesoporeal zeolite catalyst. The isomerization catalyst may also include a support and an active metal. The support can be selected from the group consisting of mesoporeal mordenite zeolite, mesoporeal ZSM-5 zeolite, or beta-zeolite. The active metal can be selected from the group consisting of copper, nickel, molybdenum, tungsten, platinum, palladium, or a combination thereof. The isomerization catalyst may contain 1% to 10% by mass of mordenite, for example, about 4% by mass of mordenite, based on the mass of the catalyst. The isomerization catalyst may be similar to a disproportionation catalyst.

[0052] Referring here to Figure 2, System 200 may be similar in some or all aspects to System 100 and may further include one or more additional processing units or separators, as will be described in more detail below. For example, as shown in Figure 2, System 200 may further include a toluene disproportionation unit 124 containing a disproportionation catalyst. The toluene disproportionation unit may be fluidly connected to a toluene separation unit 107, specifically downstream of the toluene column 109, and may be configured to receive at least a portion of the toluene feed stream 15 as a toluene disproportionation feed stream 16.

[0053] Although not limited by theory, the toluene disproportionation unit 124 may be included in the system to constitute excess toluene as a feed for the hybrid transalkylation / dealkylation unit 116. For example, in the embodiment, C 9+ The mass ratio of toluene feed stream 15 to hydrocarbon stream 18 can range from 0.3 to 3.0. However, as this ratio continues to increase, especially beyond 1.5, the TMB and toluene to xylene, as well as other C23s, can increase. 9+ The desired transalkylation ratio of the aromatic compound / xylene pair may decrease, and proportionally, the disproportionation of toluene to xylene and benzene may increase. Therefore, the toluene disproportionation unit 124 may be included in the system to alleviate at least some of the burden on the hybrid transalkylation / dealkylation unit 116 and to reduce the ratio within the hybrid transalkylation / dealkylation unit 116 to an optimal level.

[0054] The disproportionation catalyst may include a mesoporeal zeolite catalyst. The disproportionation catalyst may also include a support and an active metal. The support can be selected from mesoporeal mordenite zeolite, mesoporeal ZSM-5 zeolite, or both. The active metal can be selected from copper, nickel, molybdenum, tungsten, platinum, palladium, or a combination thereof. The disproportionation catalyst may contain 1% to 10% by mass of mordenite, for example, about 4% by mass of mordenite. The disproportionation catalyst may be similar to the isomerization catalyst.

[0055] The toluene disproportionation unit 124 can also be operated at operating temperatures ranging from 200°C to 540°C. The toluene disproportionation unit 124 can also be operated at operating pressures ranging from 1 MPa to 5 MPa. The toluene disproportionation unit 124 operates for 0.1 hours. -1 from 20hr -1 It can also operate at liquid space velocity.

[0056] Referring here to Figures 1-2, embodiments of this specification also include an integrated process for producing paraxylene. This process may include any of the previously described integrated systems 100-200. This process includes catalytically reforming a naphtha feed stream 2 to form a reformed oil stream 4, and reforming the reformed oil stream 4 with C1-C7 hydrocarbon streams 6 and C 8+ The process may include steps of separating the C1-C7 hydrocarbon stream 8, exposing the C1-C7 hydrocarbon stream 6 to a first solvent 5 in a solvent extraction unit 106 to form a non-aromatic hydrocarbon stream 10 and a C6-C7 aromatic compound stream 12, and separating the C6-C7 aromatic compound stream 12 to form at least a toluene feed stream 15.

[0057] This process is C 8+ Hydrocarbon flow 8 C 9+The process may further include separating the hydrocarbon stream 18 and the xylene stream 20, separating the xylene stream 20 in a p-xylene separation unit 118 to form a para-xylene stream 29 and a xylene isomer stream 30, and isomerizing the xylene isomer stream 30 with an isomerization catalyst to produce a para-xylene-rich stream 31. This process may further include separating the hydrocarbon stream 22 and the toluene feed stream 15 and C in a hybrid transalkylation / dealkylation unit 116 with a hybrid transalkylation / dealkylation catalyst. 9+ The process may also include a step of upgrading the hydrocarbon flow 18 to generate a product flow 24. In the embodiment, C 9+ The ratio of the toluene supply flow 15 to the hydrocarbon flow 18 may be between 0.3 and 3.

[0058] As previously stated, the additional flows generated within the hybrid transalkylation / dealkylation unit 116 can be used to enhance the production of paraxylene, such as by being recirculated in one or more units of the systems 100-200 described herein. For example, in an embodiment, this process may include: combining an additional non-aromatic hydrocarbon flow 10 with the non-aromatic hydrocarbon flow 10; combining an additional C6-C7 aromatic compound flow 12 with the C6-C7 aromatic compound flow 12; combining an additional xylene flow 20 and a paraxylene-rich flow 31 with the xylene flow 20; and an unconverted C9 hydrocarbon flow and an unconverted C 10+ Hydrocarbon fraction flow C 9+ The process may further include a step of combining it with a hydrocarbon flow 18.

[0059] As shown in Figures 1 and 2, in the toluene separation unit 107, the step of forming the toluene feed stream 15 may further include the step of separating the C6-C7 aromatic compound stream 12 into a benzene-rich stream 13 and a toluene-rich stream 14 in the benzene column 108, etc. The step of forming the toluene feed stream 15 may also include the step of separating the toluene feed stream 15 from the toluene-rich stream 14 in the toluene column 109, etc. As shown in Figure 2, this process is C 9+ The procedure may also include sending at least a portion of the toluene supply stream 15, along with a disproportionation catalyst, to a toluene disproportionation unit 124, such as when the ratio of the toluene supply stream 15 to the hydrocarbon stream 18 is greater than 1.5 to 3, to form an additional benzene-rich stream 13 and an additional xylene stream 20.

[0060] Furthermore, referring to Figures 1 and 2, this process involves the unconverted C9 hydrocarbon flow and the unconverted C in the hybrid transalkylation / dealkylation unit 116. 10+ Hydrocarbon fraction C 9+ The process may also include upgrading with a hydrocarbon stream 18 to form an additional product stream 24. [Examples]

[0061] Various embodiments of processes and systems for converting naphtha feedstreams to paraxylene will become even more apparent from the following examples. These embodiments are illustrative in nature and should not be understood as limiting the subject matter of this disclosure.

[0062] Two pilot plant experiments were conducted according to the embodiment described earlier and shown in Figure 1. Example 1 involved unconverted C 9+ In Example 2, the hydrocarbon fraction 26 was not recirculated, i.e., it was a basic case of a single pass. In subsequent operation, C 10+ To demonstrate the functionality of the hybrid transalkylation / dealkylation unit 116 for converting aromatic compound fractions, the unconverted C 9+This includes the recirculation of hydrocarbon fraction 26. The results of two examples are shown in Table 1 below.

[0063] [Table 1]

[0064] As shown in Table 1 above, C 10+ The conversion rate of aromatic compounds is the unconverted C 9+ After recycling the hydrocarbon fraction 26, the carbon dioxide increased by approximately 4 percent, and the hybrid transalkylation / dealkylation unit 116 and the hybrid transalkylation / dealkylation catalyst were converted by further operation. 10+ This demonstrates that hydrocarbon fractions can be dealkylated. Unconverted C 10+ The hydrocarbon fraction was monitored in the product flow by gas chromatography analysis of samples taken every 3 to 6 hours. This gas chromatography analysis revealed a C content higher than that of Example 1. 10+ No signs of increased hydrocarbon fraction accumulation were observed.

[0065] Furthermore, as shown in Table 1 and Figure 3, the total BTX yield remained relatively constant between the basic case (Example 1) and subsequent operation (Example 2). However, the decrease in the yields of benzene and toluene correlated with the increase in the yield of the desired product, xylene. While not limited to theory, this may also indicate a tendency for the transalkylation and dealkylation functions of the catalyst to work in coordination, i.e., to have a synergistic effect. Specifically, the dealkylation function of the catalyst is C 10+ Hydrocarbon fractions such as TMB 9+The catalyst can be operated to selectively dealkylate aromatic fractions. Subsequently, the catalyst's transalkylation function selectively transalkylates toluene, generating TMB in situ, which can then produce xylene in a preferred transalkylation reaction, for example. In addition, the dealkylation function also yields toluene and mixed xylene as products, which is thought to contribute to an increase in the yield of xylene.

[0066] This disclosure may include one or more embodiments. According to the first embodiment, an integrated process for producing paraxylene, either alone or in combination with any other embodiment, comprises the steps of catalytically reforming a naphtha feed stream to form a reformed oil stream; and reforming this reformed oil stream into a C1-C7 hydrocarbon stream and C 8+ Steps to separate into hydrocarbon streams; steps to expose the C1-C7 hydrocarbon streams to a first solvent in a solvent extraction unit to form non-aromatic hydrocarbon streams and C6-C7 aromatic compound streams; steps to separate the C6-C7 aromatic compound streams into at least a toluene feed stream; C 8+ Hydrocarbon flow C 9+ A step of separating the hydrocarbon flow into a xylene flow containing orthoxylene, metaxylene, and paraxylene; a step of separating the xylene flow in a p-xylene separation unit to form a paraxylene flow and a xylene isomer flow containing orthoxylene and metaxylene; a step of isomerizing the xylene isomer flow with an isomerization catalyst to produce a paraxylene-rich flow; and a step of separating the toluene feed flow and C in a hybrid dealkylation / transalkylation unit. 9+ A step of upgrading a hydrocarbon flow with a hydrogen flow and a hybrid transalkylation / dealkylation catalyst to produce a product flow containing paraxylene, wherein the toluene feed flow is C 9+ The process includes a step in which the mass ratio of the hydrocarbon flow is between 0.3 and 3.

[0067] According to the second embodiment, either alone or in combination with any other embodiment, the process comprises a product stream consisting of an additional non-aromatic hydrocarbon stream, an additional C6-C7 aromatic compound stream, an unconverted C9 hydrocarbon fraction stream, and an unconverted C 10+The process may further include separating the hydrocarbon fraction stream into an additional xylene stream.

[0068] According to the third aspect, either alone or in combination with any other aspect, the process comprises an unconverted C9 hydrocarbon fraction stream and an unconverted C 10+ Hydrocarbon fraction flow C 9+ The process involves combining the hydrocarbon stream with the unconverted C9 hydrocarbon stream and the unconverted C9 hydrocarbon stream within the hybrid transalkylation / dealkylation unit. 10+ The process may further include upgrading the hydrocarbon distillation flow to form an additional product flow.

[0069] According to a fourth embodiment, either alone or in combination with any other embodiment, the process may further include the steps of combining an additional C6-C7 aromatic compound stream and the C6-C7 aromatic compound stream, and separating the combined C6-C7 aromatic compound stream into an additional toluene feed stream and a benzene-rich stream.

[0070] According to a fifth embodiment, the process may further include, either alone or in combination with any other embodiment, a step of combining an additional non-aromatic hydrocarbon stream with a non-aromatic hydrocarbon stream, and a step of combining an additional xylene stream and a para-xylene-rich stream with a xylene stream.

[0071] According to the sixth embodiment, either alone or in combination with any other embodiment, the hybrid transalkylation / dealkylation catalyst comprises a solid zeolite complex and an active metal, wherein the solid zeolite complex comprises large-pore mordenite and intermediate-pore ZSM-5 in a mass ratio of large-pore mordenite to intermediate-pore ZSM-5 from 1:1 to 5:1, and the active metal is selected from the group consisting of molybdenum, chromium, platinum, nickel, palladium, rhenium, or a combination thereof.

[0072] According to the seventh embodiment, the active metal of the hybrid transalkylation / dealkylation catalyst is molybdenum, either alone or in combination with any other embodiment.

[0073] According to the eighth aspect, either alone or in combination with any other aspect, the hybrid transalkylation / dealkylation catalyst has a mesostructure comprising at least one disordered intermediate phase and at least one ordered intermediate phase.

[0074] According to the ninth aspect, either alone or in combination with any other aspect, toluene supply flow versus C 9+ The hydrocarbon flow ratio is greater than 1.5 to 3, and the process further includes the step of sending at least a portion of the toluene feed stream together with a disproportionation catalyst to a disproportionation unit to form an additional xylene stream and a benzene-rich stream.

[0075] According to the tenth embodiment, the disproportionation catalyst, either alone or in combination with any other embodiment, comprises a support selected from the group consisting of mesopore ZSM-5 zeolite and mesopore mordenite zeolite, and an active metal selected from the group consisting of copper, nickel, molybdenum, tungsten, platinum, palladium, or a combination thereof.

[0076] According to the 11th embodiment, either alone or in combination with any other embodiment, the reforming catalyst comprises a support and a noble metal, the support comprising silica, alumina, or silica-alumina, the noble metal comprising platinum, rhenium, or both, the first solvent comprising sulfolane, n-methylpyrrolidone, dimethyl sulfoxide, n-formylmorpholine, polyglycol, or a combination thereof, and the isomerization catalyst comprising a support selected from the group consisting of fluorinated zeolite, mesopore ZSM-5 zeolite, and mesopore mordenite zeolite, and an active metal selected from the group consisting of copper, nickel, molybdenum, tungsten, platinum, palladium, or a combination thereof.

[0077] According to the 12th embodiment, isomerization and disproportionation, either alone or in combination with any other embodiment, occur at a temperature in the range of 200°C to 540°C, a pressure in the range of 1 MPa to 5 MPa, and 0.1 hr. -1 from 20hr -1 It is carried out at the liquid space velocity.

[0078] According to the 13th aspect, hybrid transalkylation / dealkylation, either alone or in combination with any other aspect, is performed at a temperature of 300°C to 480°C, a pressure of 1 MPa to 3 MPa, and for 0.1 hours. -1 from 10hr -1 This is performed using the liquid space velocity and hydrogen-to-supply ratios from 1 to 6.

[0079] According to the 14th aspect, an integrated system for producing paraxylene, either alone or in combination with any other aspect, may comprise: a catalytic reformer containing a reforming catalyst; a first separation device fluidly connected downstream of the catalytic reformer; a solvent extraction unit containing a first solvent, fluidly connected downstream of the first separation device; a toluene separation unit fluidly connected downstream of the solvent extraction unit; a xylene separation unit fluidly connected downstream of the first separation device; a hybrid transalkylation / dealkylation unit containing a hybrid transalkylation / dealkylation catalyst, fluidly connected downstream of the toluene separation unit and the xylene separation unit; a p-xylene separation unit fluidly connected downstream of the xylene separation unit; and a xylene isomerization unit containing an isomerization catalyst, fluidly connected downstream and upstream of the p-xylene separation unit.

[0080] According to the 15th embodiment, either alone or in combination with any other embodiment, the toluene separation unit includes a benzene column fluid-connected downstream of a solvent extraction unit, and a toluene column fluid-connected downstream of the benzene column and upstream of a hybrid transalkylation / dealkylation unit.

[0081] According to the sixteenth embodiment, either alone or in combination with any other embodiment, the system further includes a sixth separator fluidly connected to a hybrid transalkylation / dealkylation unit, a benzene column, a xylene separation unit, and a p-xylene separation unit, the sixth separator being downstream of the hybrid transalkylation / dealkylation unit and upstream of the benzene column, the xylene separation unit, and the p-xylene separation unit.

[0082] According to the 17th embodiment, either alone or in combination with any other embodiment, the system further includes a toluene disproportionation unit comprising a disproportionation catalyst, which is fluidly connected downstream of a toluene column and upstream of a p-xylene separation unit.

[0083] According to the 18th aspect, either alone or in combination with any other aspect, the reforming catalyst comprises a support and a noble metal, the support comprising silica, alumina, or silica-alumina, the noble metal comprising platinum, rhenium, or both, the first solvent comprising sulfolane, n-methylpyrrolidone, dimethyl sulfoxide, n-formylmorpholine, polyglycol, or a combination thereof, and the isomerization catalyst and disproportionation catalyst are selected from the group consisting of fluorinated zeolite, mesopore ZSM-5 zeolite, and mesopore mordenite zeolite. The hybrid transalkylation / dealkylation catalyst comprises a support and an active metal selected from the group consisting of copper, nickel, molybdenum, tungsten, platinum, palladium, or a combination thereof. The solid zeolite complex comprises large-pore mordenite and intermediate-pore ZSM-5 in a mass ratio of large-pore mordenite to intermediate-pore ZSM-5 from 1:1 to 5:1, and the active metal is selected from the group consisting of molybdenum, chromium, platinum, nickel, palladium, rhenium, or a combination thereof.

[0084] According to the 19th aspect, the active metal of the hybrid transalkylation / dealkylation catalyst is molybdenum, either alone or in combination with any other aspect.

[0085] According to the 20th aspect, the xylene isomerization unit and the toluene disproportionation unit operate at a temperature in the range of 200°C to 540°C, a pressure in the range of 1 MPa to 5 MPa, and a liquid hourly space velocity of 0.1 hr -1 to 20 hr -1 The hybrid transalkylation / dealkylation unit operates at a temperature of 300°C to 480°C, a pressure of 1 MPa to 3 MPa, a liquid hourly space velocity of 0.1 hr -1 to 10 hr -1 and a hydrogen-to-feed ratio of 1 to 6.

[0086] Note that the description in this disclosure that a component of the present disclosure is "operable" or "sufficient" in a particular way to embody a particular property or function in a particular way is a structural description, in contrast to a description of the intended use. More specifically, in this disclosure, a reference to the manner in which a component is "operable" or "sufficient" indicates the existing physical state of the component and, as such, is considered a clear reference to the structural features of the component.

[0087] Also, terms such as "preferably," "generally," and "typically" are not used in this specification to limit the scope of the invention claimed or to imply that a particular feature is critical, essential, or even important to the structure or function of the invention claimed. Rather, these terms are merely intended to identify particular aspects of embodiments of the present disclosure or to highlight alternative or additional features that may or may not be utilized in particular embodiments of the present disclosure.

[0088] Note that the term “here” is used as a transitional clause in one or more of the following claims. Note that for the purpose of defining the present invention, this term is introduced into the claims as an unrestricted transitional clause used to introduce an enumeration of a set of structural features and should be interpreted similarly to the more commonly used unrestricted postscript “includes.”

[0089] While the subject matter of this disclosure has been described in detail and with reference to specific embodiments, it should be noted that the various details disclosed in this disclosure should not be interpreted as implying that these details relate to elements that are essential components of the various embodiments described herein. Furthermore, it will be apparent that modifications and alterations are possible without departing from the scope of this disclosure, including, but not limited to, the embodiments defined in the appended claims.

[0090] The singular form includes multiple subjects unless it is clearly determined from the context that it does not.

[0091] Through this disclosure, a range is provided. Each discrete value included within the range is also assumed to be included. Furthermore, the range that may be formed by each discrete value included by the explicitly disclosed range is also assumed.

[0092] As used herein and in the appended claims, the words “comprise,” “has,” and “include,” and all their grammatical variations, are intended to have an open, non-restrictive meaning that does not exclude any additional elements or processes.

[0093] Where used herein, terms such as “First” and “Second” are arbitrarily assigned and intended solely to distinguish two or more examples or components. It should be understood that the words “First” and “Second” serve no other purpose, are not part of the names or descriptions of components, and do not necessarily define the relative location, position, or order of components. Furthermore, it should be understood that the mere use of the terms “First” and “Second” does not require the existence of any “Third” component, although such possibility is conceivable within the scope of this disclosure. [Explanation of Symbols]

[0094] 2. Naphtha supply flow 4 Modified oil flow 5. The first solvent 6 C1-C7 hydrocarbon flow 8 C 8+ Hydrocarbon flow 10 Non-aromatic hydrocarbon flow 12 C6~C7 aromatic compound flow 13. Abundant flow of benzene 14. Abundant Toluene Flow 15 Toluene supply flow 16. Toluene disproportionation supply flow 18 C 9+ Hydrocarbon flow 20 xylene flow 22 Hydrogen Stream 24 Product logistics 26 C 9+ Hydrocarbon flow 29 Paraxylene Flow 30 Xylene isomer flow 31. Abundant flow of paraxylene 100, 200 integrated systems 102 Contact reforming device 104 First Separator 106 Solvent Extraction Unit 107 Toluene Separation Unit 108 Benzene column, second separator 109 Toluene column, third separator 110 Xylene separation unit, fourth separator 116 Hybrid transalkylation / dealkylation unit 118 p-xylene separation unit, fifth separator 120 xylene isomerization unit 122 The sixth separator 124 Toluene disproportionation unit

Claims

1. In the integrated process for producing paraxylene, A process of catalytically reforming a naphtha supply flow to form a reformed oil flow. The modified oil flow is C １ ~C ７ Hydrocarbon flow and C ８＋ The process of separating into hydrocarbon streams. Within the solvent extraction unit, C １ ~C ７ The hydrocarbon stream is exposed to the first solvent, and the non-aromatic hydrocarbon stream and C ６ ~C ７ A process for forming a flow of aromatic compounds, Said C ６ to C ７ A step of separating an aromatic compound stream into at least a toluene feed stream Said C ８＋ Hydrocarbon flow C ９＋ A process of separating a hydrocarbon stream and a xylene stream containing orthoxylene, metaxylene, and paraxylene. A step of separating the xylene stream in a p-xylene separation unit to form a para-xylene stream and a xylene isomer stream containing orthoxylene and metaxylene, A step of isomerizing the xylene isomer stream with an isomerization catalyst to generate a paraxylene-rich stream, and The toluene supply stream and the C within the hybrid dealkylation / transalkylation unit ９＋ A step of upgrading a hydrocarbon stream with a hydrogen stream and a hybrid transalkylation / dealkylation catalyst to produce a product stream containing paraxylene, wherein the toluene feed stream is compared with the C ９＋ Process where the mass ratio of the hydrocarbon flow is between 0.3 and 3. A process that includes this.

2. The product flow is an additional non-aromatic hydrocarbon flow, an additional C ６ ~C ７ Aromatic compound flow, unconverted C ９ Hydrocarbon fractionation flow, unconverted C １０＋ The process according to claim 1, further comprising the step of separating into a hydrocarbon fraction stream and an additional xylene stream.

3. The previously unconverted C ９ Hydrocarbon fractional flow and the unconverted C １０＋ The hydrocarbon fraction flow is C ９＋ The process involves combining with a hydrocarbon flow, and the unconverted C in the hybrid transalkylation / dealkylation unit. ９ Hydrocarbon fractional flow and the unconverted C １０＋ A process to upgrade the hydrocarbon distillation flow and form an additional product flow. The aforementioned additional C ６ ~C ７ Aromatic compound flow and the C ６ ~C ７ The process of combining aromatic compound streams, and the combined C ６ ~C ７ A process of separating an aromatic compound flow into an additional toluene feed flow and a benzene-rich flow, or A step of combining the additional non-aromatic hydrocarbon flow with the non-aromatic hydrocarbon flow, and a step of combining the additional xylene flow and the para-xylene-rich flow with the xylene flow. The process according to claim 2, further comprising at least one of the following.

4. The aforementioned hybrid transalkylation / dealkylation catalyst comprises a solid zeolite composite and an activated metal. The solid zeolite composite contains large-pore mordenite and intermediate-pore ZSM-5 in a mass ratio of large-pore mordenite to intermediate-pore ZSM-5 of 1:1 to 5:

1. The process according to any one of claims 1 to 3, wherein the active metal is selected from the group consisting of molybdenum, chromium, platinum, nickel, palladium, rhenium, or a combination thereof.

5. The process according to claim 4, wherein the active metal of the hybrid transalkylation / dealkylation catalyst is molybdenum.

6. The process according to claim 4 or 5, wherein the hybrid transalkylation / dealkylation catalyst has a mesostructure comprising at least one disordered intermediate phase and at least one ordered intermediate phase.

7. The toluene supply flow convection ９＋ The ratio of hydrocarbon flow is greater than 1.5 to 3. The process according to any one of claims 1 to 6, further comprising the step of sending at least a portion of the toluene supply stream together with a disproportionation catalyst to a disproportionation unit to form an additional xylene stream and a benzene-rich stream.

8. The disproportionation catalyst, A carrier selected from the group consisting of mesopore ZSM-5 zeolite and mesopore mordenite zeolite, and Active metals selected from the group consisting of copper, nickel, molybdenum, tungsten, platinum, palladium, or combinations thereof. The process according to claim 7, including the process described in claim 7.

9. The reforming catalyst comprises a support and a noble metal, the support comprising silica, alumina, or silica-alumina, and the noble metal comprising platinum, rhenium, or both. The first solvent comprises sulfolane, n-methylpyrrolidone, dimethyl sulfoxide, n-formylmorpholine, polyglycol, or a combination thereof. The process according to any one of claims 1 to 8, wherein the isomerization catalyst comprises a support selected from the group consisting of fluorinated zeolite, mesopore ZSM-5 zeolite, and mesopore mordenite zeolite, and an active metal selected from the group consisting of copper, nickel, molybdenum, tungsten, platinum, palladium, or a combination thereof.

10. In an integrated system for generating paraxylene, Catalytic reforming apparatus including reforming catalyst, A first separation device is fluid-connected downstream of the aforementioned contact reforming device. A solvent extraction unit comprising a first solvent, wherein the solvent extraction unit is fluidly connected downstream of the first separation device. A toluene separation unit is fluidly connected downstream of the solvent extraction unit. A xylene separation unit is fluidly connected downstream of the first separation device. A hybrid transalkylation / dealkylation unit comprising a hybrid transalkylation / dealkylation catalyst, wherein the hybrid transalkylation / dealkylation unit is fluidly connected downstream of the toluene separation unit and the xylene separation unit. A p-xylene separation unit is fluidly connected downstream of the xylene separation unit, and A xylene isomerization unit containing an isomerization catalyst, wherein the xylene isomerization unit is fluidly connected downstream and upstream of the p-xylene separation unit. A system equipped with these features.

11. The toluene separation unit, A benzene column fluidly connected downstream of the solvent extraction unit, and A toluene column is fluid-connected downstream of the benzene column and upstream of the hybrid transalkylation / dealkylation unit. The system according to claim 10, including the following:

12. The system according to claim 11, further comprising the hybrid transalkylation / dealkylation unit, the benzene column, the xylene separation unit, and a sixth separator fluidly connected to the p-xylene separation unit, wherein the sixth separator is downstream of the hybrid transalkylation / dealkylation unit and upstream of the benzene column, the xylene separation unit, and the p-xylene separation unit.

13. The system according to claim 11 or 12, further comprising a toluene disproportionation unit containing a disproportionation catalyst, the toluene disproportionation unit being fluidly connected downstream of the toluene column and upstream of the p-xylene separation unit.

14. The reforming catalyst comprises a support and a noble metal, the support comprising silica, alumina, or silica-alumina, and the noble metal comprising platinum, rhenium, or both. The first solvent comprises sulfolane, n-methylpyrrolidone, dimethyl sulfoxide, n-formylmorpholine, polyglycol, or a combination thereof. The isomerization catalyst and the disproportionation catalyst each contain a support selected from the group consisting of fluorinated zeolite, mesopore ZSM-5 zeolite, and mesopore mordenite zeolite, and an active metal selected from the group consisting of copper, nickel, molybdenum, tungsten, platinum, palladium, or a combination thereof. The aforementioned hybrid transalkylation / dealkylation catalyst comprises a solid zeolite complex and an active metal, wherein the solid zeolite complex contains large-pore mordenite and intermediate-pore ZSM-5 in a mass ratio of large-pore mordenite to intermediate-pore ZSM-5 from 1:1 to 5:1, and the active metal is selected from the group consisting of molybdenum, chromium, platinum, nickel, palladium, rhenium, or a combination thereof. The system according to claim 13, wherein the active metal of the hybrid transalkylation / dealkylation catalyst is molybdenum.

15. The xylene isomerization unit and the toluene disproportionation unit operate at a temperature in the range of 200°C to 540°C, a pressure in the range of 1 MPa to 5 MPa, and 0.1 hr －１ 20 hours from －１ It operates at a liquid space velocity, The aforementioned hybrid transalkylation / dealkylation unit operates at a temperature of 300°C to 480°C, a pressure of 1 MPa to 3 MPa, and for 0.1 hours. －１ From 10 hours －１ The system according to claim 13 or 14, which operates with a liquid space velocity and a hydrogen-to-supply ratio of 1 to 6.

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