Two-stage fixed bed catalytic process for upgrading pyrolysis oil to BTX

Abstract

A process for upgrading a pyrolysis oil comprising contacting a pyrolysis oil feed with hydrogen in a first fixed bed reactor in the presence of a mixed metal oxide catalyst wherein: the pyrolysis oil feed comprises a polycyclic aromatic hydrocarbon compound comprising greater than or equal to 16 carbon atoms; and contacting the pyrolytic oil feedstock with hydrogen in the presence of a mixed metal oxide catalyst in a first fixed bed reactor to convert at least a portion of the polycyclic aromatic hydrocarbon compounds in the pyrolytic oil feedstock into bicyclic aromatic hydrocarbon compounds, tricyclic aromatic hydrocarbon compounds, or both, passing the intermediate stream comprising the bicyclic aromatic compound, the tricyclic aromatic compound, or both to a second fixed bed reactor downstream of the first fixed bed reactor; and contacting the intermediate stream with hydrogen in the presence of a mesoporous supported metal catalyst in a second fixed bed reactor.

Description

Cross-references to related applications

[0001] This application claims priority to U.S. Patent Application Serial No. 18 / 355,789, filed July 20, 2023, the entire disclosure of which is incorporated herein by reference. Background Technology

[0002] field This disclosure generally relates to methods and systems for upgrading pyrolysis oil, and more specifically, to methods and systems for upgrading pyrolysis oil to light aromatic compounds using a two-stage fixed-bed catalytic process. Technical Background Crude oil can be converted into valuable chemical intermediates and products through one or more refining processes. Refining processes may include steam cracking, where large hydrocarbon molecules in crude oil are cracked into smaller hydrocarbon molecules. For example, naphtha streams separated from crude oil and condensate streams can be steam cracked to produce higher-value products and intermediates. Light hydrocarbon gases can also be steam cracked to produce higher-value products and intermediates, such as, but not limited to, olefins. The steam cracking unit produces a bottom stream called pyrolysis oil. Compared to crude oil feedstock, pyrolysis oil may contain a higher concentration of aromatic compounds. In many crude oil processing facilities, this pyrolysis oil is burned as fuel. However, the aromatic compounds in pyrolysis oil can be converted into higher-value chemical products and intermediates, which can be used as base feedstocks in chemical synthesis processes. For example, aromatic compounds in pyrolysis oil can be converted into xylene, which can be used as an initial base feedstock for the production of terephthalic acid, which in turn can be used to produce polyesters. Aromatic compounds in pyrolysis oil can be upgraded into many other higher-value aromatic products and intermediates. Market demand for these higher-value aromatic compounds continues to grow. Summary of the Invention

[0004] Polycyclic aromatic hydrocarbons (PAHs) in pyrolysis oils can be converted into light aromatic hydrocarbons through various reactions, including benzene, toluene, ethylbenzene, xylene (BTEX), other aromatic compounds, or combinations thereof. These reactions include, but are not limited to, hydrogenation, ring-opening, disproportionation, dealkylation, alkyl transfer, cracking, or aromatic cracking. Typically, combinations of these reactions can convert a portion of the PAHs in the pyrolysis oil into light aromatic hydrocarbons in a single step. However, completing multiple reactions in a single processing step can be complex, and the yield may be insufficient to meet the demand for BTEX. Furthermore, achieving these reaction combinations may be difficult without stringent conditions.

[0005] Therefore, there is a need for improved systems and methods for upgrading pyrolysis oil to produce light aromatic compounds under mild processing conditions, thereby increasing the yield of BTEX. Embodiments of this disclosure meet this need by providing a two-stage catalytic method that upgrades pyrolysis oil to BTEX in a single process using two fixed-bed reactors in series. The first fixed-bed reactor may include a mixed metal oxide catalyst configured for use in the fixed-bed reactor. The first fixed-bed reactor can operably convert at least a portion of the polycyclic aromatic compounds in the pyrolysis oil to intermediate aromatic compounds, such as bicyclic diaromatic compounds. The second fixed-bed reactor may include a mesoporous supported metal catalyst and can operably convert at least a portion of the intermediate aromatic compounds to BTEX. This method and system can convert a portion of the polycyclic aromatic compounds in the pyrolysis oil to BTEX in a two-stage fixed-bed catalytic process without subsequent chemical reaction steps. Compared to conventional methods for upgrading pyrolysis oil using more stringent reaction conditions, this method and system also produce higher yields of BTEX by upgrading the pyrolysis oil under milder conditions.

[0006] According to one or more aspects of this disclosure, a method for upgrading pyrolysis oil may include: contacting a pyrolysis oil feed with hydrogen in a first fixed-bed reactor in the presence of a mixed metal oxide catalyst; and contacting an intermediate stream with hydrogen in a second fixed-bed reactor in the presence of a mesoporous supported metal catalyst. The mesoporous supported metal catalyst may comprise nickel and tungsten impregnated on a mesoporous support comprising macroporous alumina, a binder, and at least one zeolite. Contacting the pyrolysis oil feed with hydrogen in the first fixed-bed reactor in the presence of the mixed metal oxide catalyst can cause at least a portion of the polycyclic aromatic hydrocarbons (PAHs) in the pyrolysis oil feed to react to produce an intermediate stream comprising bicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons, or combinations thereof. Contacting the intermediate stream with hydrogen in the presence of the mesoporous supported metal catalyst can cause at least a portion of the bicyclic aromatic hydrocarbons and / or tricyclic aromatic hydrocarbons in the intermediate stream to react to produce a second reactor effluent comprising an aromatic hydrocarbon having 6 to 8 carbon atoms. The pyrolysis oil feed may contain polycyclic aromatic hydrocarbons having sixteen or more carbon atoms. The mixed metal oxide catalyst may contain multiple MMO particles, and each of the multiple MMO particles contains Fe2O3, ZrO2, CeO2, and Al2O3.

[0007] According to one or more aspects of this disclosure, a system for upgrading pyrolysis oil may include a first fixed-bed reactor and a second fixed-bed reactor. The first fixed-bed reactor includes a mixed metal oxide catalyst, and the second fixed-bed reactor is located downstream of the first fixed-bed reactor and includes a mesoporous supported metal catalyst. The first fixed-bed reactor can be operable to contact the pyrolysis oil feed with hydrogen in the presence of the mixed metal oxide catalyst to produce an intermediate stream comprising a bicyclic aromatic compound, a tricyclic aromatic compound, or both. The mixed metal oxide catalyst may comprise a plurality of catalyst particles, and each of the plurality of catalyst particles may comprise Fe₂O₃, ZrO₂, CeO₂, and Al₂O₃. The second fixed-bed reactor can be operable to contact the intermediate stream with hydrogen in the presence of the mesoporous supported metal catalyst to produce a second reactor effluent comprising an aromatic compound having 6 to 8 carbon atoms. The mesoporous supported metal catalyst may comprise nickel and tungsten impregnated on a mesoporous support comprising alumina and at least one zeolite.

[0008] Other features and advantages of the technology described in this disclosure will be set forth in the detailed description below, and some features and advantages will be readily apparent to those skilled in the art from the specification or by practicing the technology described in this disclosure, including the detailed description below, the claims, and the drawings.

[0009] Brief description of the attached figures The following detailed description of specific embodiments of this disclosure can be best understood when read in conjunction with the accompanying drawings, wherein the same structures are indicated by the same reference numerals, and wherein: Figure 1 A general flow diagram of a system for upgrading pyrolysis oil according to one or more embodiments shown and described in this disclosure is schematically depicted; Figure 2 A general flow diagram of a system for providing pyrolysis oil feed according to one or more embodiments shown and described in this disclosure is schematically depicted; Figure 3 A general flow diagram of a system for providing pyrolysis oil feed according to one or more embodiments shown and described in this disclosure is schematically depicted; Figure 4 The composition of heavy pyrolysis oil is depicted graphically; and Figure 5 A general flow diagram of a system for upgrading pyrolysis oil according to one or more embodiments shown and described in this disclosure is schematically depicted; Figure 6 A general flow diagram of a system for upgrading pyrolysis oil according to one or more embodiments shown and described in this disclosure is schematically depicted.

[0010] To describe Figures 1 to 3 and Figure 5 The simplified diagrams and descriptions shown do not include numerous valves, temperature sensors, electronic controllers, and other components commonly used in chemical processing operations that are well-known to those skilled in the art. Furthermore, commonly included components in chemical processing operations, such as gas supply systems, heat exchangers, buffer tanks, catalyst hoppers, or other related systems, are not depicted. It should be understood that these components are all within the spirit and scope of this disclosure. However, operational components, such as those described in this disclosure, can be added to the embodiments described herein.

[0011] It should also be noted that the arrows in the diagram represent process flows. However, arrows can also equivalently represent transfer lines used to transfer process flows between two or more system components. Furthermore, arrows connected to system components define the inlet or outlet of each given system component. The direction of the arrows generally aligns with the primary flow direction of the material contained within the physical transfer line represented by the arrow. Additionally, arrows not connecting two or more system components represent product flows leaving the illustrated system or system inlet flows entering the illustrated system. Product flows may be further processed in an associated chemical processing system or may be commercialized as a final product. System inlet flows may be flows transferred from an associated chemical processing system or untreated feed streams. Some arrows may represent recycling flows, i.e., effluent streams from system components that are recycled back into the system. However, it should be understood that in some embodiments, any represented recycling flow may be replaced by a system inlet flow of the same material, and a portion of the recycling flow may leave the system as a system product.

[0012] Furthermore, the arrows in the illustrations can schematically depict process steps that transfer a flow from one system component to another. For example, an arrow pointing from one system component to another can indicate the "transfer" of the effluent from one system component to another. This can include the contents of the process flow "leaving" or being "removed" from one system component and the contents of that product flow being "introduced" to another system component.

[0013] It should be understood that when Figures 1 to 3 and Figure 5 In a schematic flow chart, when two or more lines intersect, it indicates that two or more process flows are "mixed" or "combined". Mixing or combining can also include introducing two flows directly into the same reactor, separator, or other system component for mixing. For example, it should be understood that when two flows are depicted as being directly combined before entering a separator or reactor, in some embodiments, these flows may be equivalently introduced into the separator or reactor and mixed within the reactor.

[0014] Various embodiments of this disclosure will now be described in more detail, some of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used in all the drawings to refer to the same or similar parts. Detailed Implementation

[0015] This disclosure relates to methods and systems for upgrading pyrolysis oil in a two-stage fixed-bed catalytic process. Now refer to... Figure 1 A system 100 for upgrading pyrolysis oil may include a first fixed-bed reactor 110 and a second fixed-bed reactor 120 located downstream of the first fixed-bed reactor 110. The first fixed-bed reactor 110 may include a mixed metal oxide catalyst 112. The first fixed-bed reactor 110 can operablely contact the pyrolysis oil feed 102 with hydrogen 116 in the presence of the mixed metal oxide catalyst 112 to produce an intermediate stream 118 comprising bicyclic aromatic compounds, tricyclic aromatic compounds, or combinations thereof. The mixed metal oxide catalyst 112 may comprise a plurality of catalyst particles, and each of the plurality of catalyst particles may comprise iron oxide (Fe₂O₃), zirconium oxide (ZrO₂), cerium oxide (CeO₂), and alumina (Al₂O₃). The second fixed-bed reactor 120 located downstream of the first fixed-bed reactor 110 may include a mesoporous supported metal catalyst 122. The second fixed-bed reactor 120 can operably contact the intermediate stream 118 with hydrogen in the presence of a mesoporous supported metal catalyst 122 to produce a second reactor effluent 130 containing an aromatic compound having 6 to 8 carbon atoms. The mesoporous supported metal catalyst 122 may comprise nickel and tungsten impregnated on a mesoporous support comprising alumina and at least one zeolite.

[0016] Still refer to Figure 1A method for upgrading pyrolysis oil includes: contacting a pyrolysis oil feed 102 with hydrogen 116 in a first fixed-bed reactor 110 in the presence of a mixed metal oxide catalyst 112. The pyrolysis oil feed 102 may contain polycyclic aromatic hydrocarbons having sixteen or more carbon atoms. The mixed metal oxide catalyst 112 may contain multiple catalyst particles, each of which may contain Fe2O3, ZrO2, CeO2, and Al2O3. Contacting the pyrolysis oil feed 102 with hydrogen 116 in the first fixed-bed reactor 110 in the presence of the mixed metal oxide catalyst 112 can cause at least a portion of the polycyclic aromatic hydrocarbons in the pyrolysis oil feed 102 to react to produce an intermediate stream containing bicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons, or both. The method may also include contacting an intermediate stream 118 with hydrogen 124 in a second fixed-bed reactor 120 in the presence of a mesoporous supported metal catalyst 122. The mesoporous supported metal catalyst 122 may comprise nickel and tungsten impregnated on a mesoporous support comprising alumina and at least one zeolite. In the presence of the mesoporous supported metal catalyst 122, contacting the intermediate stream 118 with hydrogen 124 can cause at least a portion of the bicyclic aromatic compounds, tricyclic aromatic compounds, or combinations thereof in the intermediate stream 118 to react to produce a second reactor effluent 130 comprising an aromatic compound having six to eight carbon atoms.

[0017] This system and method demonstrate improved performance in upgrading crude pyrolysis oil into a high-value aromatic stream in a fixed-bed catalytic process. The overall yield of monocyclic aromatics can be significantly higher than previous systems. Furthermore, this yield can be achieved using a crude heavy pyrolysis oil feed stream and a fixed-bed system. The use of a fixed-bed system also eliminates the need for a separate step to separate the solid catalyst from the reactor effluent.

[0018] As used in this disclosure, the term "catalyst" refers to any substance that increases the rate of a particular chemical reaction. The catalysts and catalyst components described in this disclosure can be used to promote a variety of reactions, such as, but not limited to, selective hydrogenation, ring opening, disproportionation, dealkylation, hydrodealkylation, alkyl transfer, cracking, aromatic cracking, other chemical reactions, or combinations thereof.

[0019] As used in this disclosure, the term "cracking" refers to a chemical reaction in which a molecule having carbon-carbon bonds breaks down into more than one molecule by breaking one or more carbon-carbon bonds; a molecule containing one or more cyclic moieties, such as, but not limited to, aromatic compounds, undergoes a reaction that opens one or more cyclic moieties; or a molecule having carbon-carbon double bonds is reduced to carbon-carbon single bonds. Some catalysts may have multiple forms of catalytic activity, and defining a catalyst by a particular function does not mean that the catalyst cannot be catalytically active for other functions. As used in this disclosure, the term "hydrocracking" refers to cracking in the presence of added hydrogen.

[0020] As used in this disclosure, the term "aromatic compound" refers to a compound having one or more aromatic rings. The term "light aromatic compound" refers to a compound having an aromatic ring (with or without substituents) and having six to eight carbon atoms. The term "BTEX" refers to one or more of benzene, toluene, ethylbenzene, p-xylene, m-xylene, and o-xylene, or any combination thereof.

[0021] As used in this disclosure, the term "xylene" refers to one or more of meta-xylene, ortho-xylene, and p-xylene, as well as mixtures of these xylene isomers, unless the isomer name is specified (e.g., prefixed with para, meta, or ortho).

[0022] Unless otherwise stated, the terms “boiling point temperature” or “boiling temperature” as used in this disclosure refer to the boiling point temperature at atmospheric pressure.

[0023] As used in this disclosure, the term “initial boiling point” or “IBP” relating to a composition refers to the temperature at which the component with the lowest boiling point in the composition begins to change from the liquid phase to the gas phase.

[0024] As used in this disclosure, the term "final boiling point" or "FBP" relating to a composition refers to the temperature at which the component with the highest boiling point in the composition transitions from the liquid phase to the gas phase.

[0025] As used in this disclosure, the term "outer surface" refers to the surface surrounding the catalyst or catalyst support (such as a mesoporous support).

[0026] As used in this disclosure, the term "pore surface" refers to the inner surface of a pore in a catalyst or catalyst support, wherein the pore includes at least a pore in fluid communication with the outer surface of the catalyst or catalyst support and is accessible to reactants.

[0027] As used in this disclosure, the term "average pore size" in relation to a catalyst or catalyst support refers to the average pore size determined by the Barrett-Joyner-Halenda (BJH) analytical method. The BJH analytical method measures the amount of gas (argon) separated from a material (such as a mesoporous support) under different pressure conditions at a temperature of 87 Kelvin. The amount of argon adsorbate removed from the pores of the material and the relative pressure of the system are used to calculate the average pore size of the material using the Kelvin equation.

[0028] As used in this disclosure, the term "fixed-bed reactor" refers to a reactor in which the catalyst is contained within and held in a fixed position within the reactor. A fixed-bed reactor as used in this disclosure may include multiple material inlets but has a single effluent outlet.

[0029] As used in this disclosure, the term "separation unit" refers to any separation device that at least partially separates one or more chemical substances in a mixture from each other. For example, a separation unit may selectively separate different chemical substances to form one or more chemical components. Examples of separation units include, but are not limited to, distillation columns, fractionators, flash tanks, knock-out drums, knock-out pots, centrifuges, filters, traps, washing towers, expansion devices, membranes, solvent extraction devices, high-pressure separators, low-pressure separators, etc. It should be understood that the separation processes described in this disclosure may not completely separate all of one chemical component from all of another chemical component. It should be understood that the separation processes described in this disclosure "at least partially" separate different chemical components from each other, and even if not explicitly stated, separation may only include partial separation. As used in this disclosure, one or more chemical components may be "separated" from a process stream to form a new process stream. Typically, a process stream may enter a separation unit and be divided or separated into two or more process streams having the desired composition.

[0030] As used in this disclosure, the terms "upstream" and "downstream" refer to the relative positioning of a unit operation with respect to the direction of process flow. If the process flow through the system encounters the first unit operation before encountering the second unit operation, the first unit operation of the system is considered to be "upstream" of the second unit operation. Similarly, if the process flow through the system encounters the first unit operation before encountering the second unit operation, the second unit operation is considered to be "downstream" of the first unit operation.

[0031] As used in this disclosure, "directly" transferring a stream or effluent from one unit to another means transferring the stream or effluent from the first unit to the second unit without subjecting the stream or effluent to an interfering reaction system or separation system that substantially alters the composition of the stream or effluent. Heat transfer devices, such as heat exchangers, preheaters, coolers, condensers, or other heat transfer equipment, and pressure devices, such as pumps, pressure regulators, compressors, or other pressure devices, are not considered interfering systems that alter the composition of the stream or effluent. Combining two streams or effluents upstream of a process unit is also not considered an interfering system involving alteration of the composition of one or both of the combined streams or effluents. Simply splitting a stream into two streams having the same composition is also not considered an interfering system involving alteration of the stream composition.

[0032] As used in this disclosure, the term "effluent" refers to a stream that flows out of a reactor, reaction zone, or separator following a specific reaction or separation process. Typically, the composition of the effluent differs from the stream entering the separator, reactor, or reaction zone. It should be understood that when an effluent is transferred to another system unit, only a portion of that system stream may be transferred. For example, a slipstream (having the same composition) may carry away some effluent, meaning that only a portion of the effluent may enter the downstream system unit. The term "reaction effluent" is used more specifically to refer to a stream flowing out of a reactor or reaction zone.

[0033] It should also be understood that a stream can be named according to its components, and the components used to name the stream can be the main components of the stream (e.g., comprising 50 wt.%, 70 wt%, 90 wt%, 95 wt%, 99 wt%, 99.5 wt%, or even 99.9 wt% to 100 wt% of the stream contents, regardless of whether any inert gas or diluent is added to the stream). It should also be understood that when a stream containing a certain component is disclosed as being transferred from one system component to another system component, that component of the stream is disclosed as being transferred from one system component to another system component. For example, a disclosed “hydrogen stream” being transferred to or from a first system component to a second system component should be understood as equivalently disclosing the transfer of “hydrogen” to or from a first system component to a second system component.

[0034] Refer again Figure 1The diagram schematically depicts a system 100 for upgrading pyrolysis oil feed 102. The system 100 may include a first fixed-bed reactor 110 and a second fixed-bed reactor 120 located downstream of the first fixed-bed reactor 110. The first fixed-bed reactor 110 may include one or more fixed-bed reactors and may operable to contact the pyrolysis oil feed 102 with hydrogen 116 in the presence of a mixed metal oxide catalyst 112 to produce an intermediate stream 118. The intermediate stream 118 may contain bicyclic aromatic compounds, tricyclic aromatic compounds, or both. The second fixed-bed reactor 120 may operable to contact the intermediate stream 118 with hydrogen 124 in the presence of a mesoporous supported metal catalyst 122 to produce a second reactor effluent 130 containing an aromatic compound having 6 to 8 carbon atoms.

[0035] This system and method demonstrate improved performance in upgrading crude pyrolysis oil into a high-value aromatic stream (containing relatively high concentrations of monocyclic aromatics) in a single process. The use of a fixed-bed reactor eliminates the need for catalyst / product separation and catalyst recycling steps.

[0036] Now refer to Figure 2 and Figure 3 The pyrolysis oil feed 102 may comprise heavy pyrolysis oil 250. In embodiments, the pyrolysis oil feed 102 may also comprise a diluent, such as, but not limited to, light pyrolysis oil, toluene, other light aromatic compounds, or combinations thereof. The heavy pyrolysis oil 250 may be a stream from a hydrocarbon processing facility rich in aromatic compounds (such as polycyclic aromatic hydrocarbons). In embodiments, the heavy pyrolysis oil 250 of the pyrolysis oil feed 102 may be a bottom stream from a liquid steam cracking process, such as a naphtha steam cracking system 200. As used herein, "bottom stream" may refer to the residue or fraction of a feed (such as a feed for a steam cracking process) that contains the least volatile components that are not separately captured as condensate vapor.

[0037] The heavy pyrolysis oil 250 in the pyrolysis oil feed 102 may contain monoaromatic compounds and polycyclic aromatic hydrocarbons (PAHs). PAHs may include aromatic compounds having 2, 3, 4, 5, 6, 7, 8, or more aromatic rings. PAHs may include aromatic compounds having sixteen or more carbon atoms. The heavy pyrolysis oil 250 in the pyrolysis oil feed 102 may also contain other components, such as, but not limited to, saturated hydrocarbons. (Refer to...) Figure 4 An exemplary embodiment of the composition of a typical heavy pyrolysis oil 250 that can be used in pyrolysis oil feed 102 is depicted graphically. Figure 4 The heavy pyrolysis oil 250 provided is a pyrolysis oil produced from steam cracking naphtha. For example... Figure 4As shown, the heavy pyrolysis oil 250 in the pyrolysis oil feed 102 may contain monocyclic aromatic hydrocarbons, bicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons, tetracyclic aromatic hydrocarbons, pentacyclic aromatic hydrocarbons, and aromatic compounds having six or more aromatic rings. Figure 2 (Hexacyclic aromatic hydrocarbons and aromatic hydrocarbons with more than six rings). For example Figure 2 As shown, the heavy pyrolysis oil 250 of the pyrolysis oil feed 102 may include a high concentration of bicyclic aromatic hydrocarbons and aromatic hydrocarbons having 6 or more aromatic rings. In an embodiment, based on the unit weight of the heavy pyrolysis oil 250 in the pyrolysis oil feed 102, the heavy pyrolysis oil 250 rich in polycyclic aromatic hydrocarbons in the pyrolysis oil feed 102 may include 50% or more of polycyclic aromatic hydrocarbons, for example, 60% or more, 65% or more, 70% or more, 75% or more, or even 80% or more of polycyclic aromatic hydrocarbons.

[0038] A significant portion of the heavy pyrolysis oil 250 in the pyrolysis oil feed 102 may be a polycyclic aromatic hydrocarbon (PAH) compound having more than 16 carbon atoms or four or more aromatic rings. The heavy pyrolysis oil 250 may include 30% by weight of PAH compounds having 16 or more carbon atoms, for example, 35% by weight, 40% by weight, or even 45% by weight of PAH compounds having 16 or more carbon atoms, where the weight percentage is based on the unit weight of the heavy pyrolysis oil 250 in the pyrolysis oil feed 102. Heavy pyrolysis oil 250 may include 30% by weight of polycyclic aromatic hydrocarbons with a boiling point of 750 degrees Fahrenheit (°F) (399°C), such as 35% by weight, 40% by weight, or even 45% by weight of polycyclic aromatic hydrocarbons with a boiling point of 399°C, wherein the weight percentage is based on the unit weight of heavy pyrolysis oil 250 in pyrolysis oil feed 102.

[0039] In the implementation plan, as determined according to the test method in ASTM D5002, the density of heavy pyrolysis oil 250 at 15°C may be greater than or equal to 1.00 g / cm³. 3 For example, greater than or equal to 1.01 g / cm³ 3 ≥1.02 g / cm³ 3 1.00 g / cm 3 Up to 1.20 g / cm 3 1.01 g / cm 3 Up to 1.10 g / cm 3 Or 1.02 g / cm 3 Up to 1.10 g / cm 3In the embodiment, the dynamic viscosity of heavy pyrolysis oil 250 at 60°C is greater than or equal to 10 mPa*s, for example, 10 mPa*s to 20 mPa*s, or 12 mPa*s to 15 mPa*s, wherein the dynamic viscosity is determined according to the test method in ASTM D7042. In the embodiment, as determined according to the test method in ASTM D7042, the kinematic viscosity of heavy pyrolysis oil 250 at 60°C is greater than or equal to 10 mm² / s. 2 / s), for example, greater than or equal to 12 mm 2 / s, 10 mm 2 / s to 20 mm 2 / s, 10 mm 2 / s to 15 mm 2 / s, 12 mm 2 / s to 20 mm 2 / s or 12 mm 2 / s to 15 mm 2 / s.

[0040] In the implementation scheme, the initial boiling point temperature (IBP) of heavy pyrolysis oil 250, as determined according to the test method in ASTM D2887, may be greater than or equal to 150°C, for example, 150°C to 200°C or 150°C to 180°C. In the implementation scheme, the final boiling point temperature (FBP) of heavy pyrolysis oil 250, as determined according to the test methods in ASTM D2887 and ISO test method EN 15199-1-3, may be greater than or equal to 500°C, for example, greater than or equal to 600°C, greater than or equal to 650°C, greater than or equal to 700°C, 500°C to 1000°C, 500°C to 900°C, 500°C to 800°C, 600°C to 1000°C, 600°C to 900°C, 600°C to 800°C, 650°C to 1000°C, 650°C to 900°C, 650°C to 800°C, 700°C to 1000°C, 700°C to 900°C, or 700°C to 800°C. In the implementation scheme, the 50% boiling point temperature of heavy pyrolysis oil 250, as determined according to the test method in ASTM D2887, may be 300°C to 500°C, such as 300°C to 450°C, 300°C to 400°C, 300°C to 380°C, 325°C to 500°C, 325°C to 450°C, 325°C to 400°C, 325°C to 380°C, 350°C to 500°C, 350°C to 450°C, 350°C to 400°C, or 350°C to 380°C.

[0041] The heavy pyrolysis oil 250 of the pyrolysis oil feed 102 may also have a low concentration of sulfur and sulfur compounds. As determined according to the test methods in ASTM D2622, the concentration of sulfur and sulfur-containing compounds in the heavy pyrolysis oil 250 of the pyrolysis oil feed 102 may be less than or equal to 1000 parts per million (ppmw), for example, less than or equal to 500 ppmw, less than or equal to 400 ppmw, or even less than or equal to 300 ppmw. In embodiments, the concentration of sulfur and sulfur-containing compounds in the heavy pyrolysis oil 250 may range from greater than 0 (zero) ppmw to 1000 ppmw, for example, 300 ppmw to 1000 ppmw or 300 ppmw to 500 ppmw. In the implementation, as determined according to the test methods in ASTM D2622, heavy pyrolysis oil 250 may have a concentration of iron, nickel, or both less than or equal to 100 ppmw, less than or equal to 50 ppmw, or less than or equal to 20 ppmw. The properties of exemplary embodiments of heavy pyrolysis oil 250 obtained from the steam cracking of naphtha are provided in Table 1.

[0042] Table 1

[0043] As previously described, in the embodiments, the pyrolysis oil feed 102 may include a diluent 104 (such as a light aromatics stream). This is due to the high viscosity of the heavy pyrolysis oil 250 (dynamic viscosity > 10 mPa*s or kinematic viscosity > 10 mm). 2 ( / s), diluent 104 can be added to increase the flowability of the pyrolysis oil feed 102. Adding diluent 104 to the pyrolysis oil feed 102 increases the surface contact between the pyrolysis oil feed 102 and the mixed metal oxide catalyst 112 in the first fixed-bed reactor 110. Diluent 104 may include, but is not limited to, light pyrolysis oil, benzene, mixed xylenes, toluene, ethylbenzene, or combinations thereof. Figure 3 As shown, in an embodiment, diluent 104 may comprise light pyrolysis oil 350 derived from the underflow of a hydrocarbon gas steam cracker. Table 1 provides the properties of one embodiment of diluent 104 comprising light pyrolysis oil 350 from a hydrocarbon gas steam cracking system. In this embodiment, the density of light pyrolysis oil 350 at 15°C is less than 0.98 g / cm³, as determined according to test methods in ASTM D5002. 3 For example, less than or equal to 0.97 g / cm³ 3 Less than or equal to 0.96 g / cm³ 3 0.92 g / cm 3 Up to 0.978 g / cm 3 Or 0.92 g / cm 3 Up to 0.97 g / cm3 In the implementation embodiment, the dynamic viscosity of light pyrolysis oil 350 at 60°C may be less than or equal to 5 mPa*s, for example, less than or equal to 4 mPa*s, 0.5 mPa*s to 5 mPa*s, 1 mPa*s to 4 mPa*s, or 1 mPa*s to 2 mPa*s, wherein the dynamic viscosity is determined according to the test method in ASTM D7042. In the implementation embodiment, as determined according to the test method in ASTM D7042, the kinematic viscosity of light pyrolysis oil 350 at 60°C may be less than or equal to 5 mm² / s (mm² / s). 2 / s), for example, less than or equal to 4 mm 2 / s, less than or equal to 2 mm 2 / s, 0.5 mm 2 / s to 5 mm 2 / s, 0.5 mm 2 / s to 4 mm 2 / s, 1 mm 2 / s to 5 mm 2 / s or 1 mm 2 / s to 2mm 2 / s.

[0044] In the implementation scheme, the initial boiling point (IBP) of light pyrolysis oil 350, as determined according to the test methods in ASTM D2887, may be less than or equal to 120°C, for example, less than 100°C, 40°C to 120°C, or 50°C to 100°C. In the implementation scheme, the final boiling point (FBP) of light pyrolysis oil 350, as determined according to the test methods in ASTM D2887, may be less than 500°C, for example, less than or equal to 450°C, less than or equal to 400°C, 250°C to less than 500°C, 250°C to 450°C, 250°C to 400°C, 300°C to less than 500°C, 300°C to 475°C, 300°C to 450°C, or 350°C to 400°C. In the implementation scheme, as determined according to the test method in ASTM D2887, the 50% boiling point temperature of light pyrolysis oil 350 may be less than 230°C, for example, 150°C to 230°C, 150°C to 225°C, 150°C to 200°C, 175°C to 230°C, 175°C to 225°C, 175°C to 200°C, 180°C to 230°C, 180°C to 225°C, or 180°C to 200°C.

[0045] The light pyrolysis oil 350 of the pyrolysis oil feed 102 may also have a low concentration of sulfur and sulfur compounds. As determined according to the test methods in ASTM D2622, the concentration of sulfur and sulfur-containing compounds in the light pyrolysis oil 350 may be less than or equal to 500 parts per million (ppmw), for example, less than or equal to 400 ppmw or even less than or equal to 300 ppmw. In embodiments, the concentration of sulfur and sulfur-containing compounds in the light pyrolysis oil 350 may range from greater than 0 (zero) ppmw to 500 ppmw, for example, 1 ppmw to 500 ppmw, 1 ppmw to 400 ppmw, or 1 ppmw to 300 ppmw. In implementations, as determined according to test methods in ASTM D2622, light pyrolysis oil 350 may have iron, nickel, or both concentrations less than or equal to 100 ppmw, less than or equal to 50 ppmw, less than or equal to 20 ppmw, or even less than or equal to 10 ppmw, for example, concentrations greater than or equal to 0 (zero) ppmw to less than or equal to 100 ppmw. Table 1 provides the properties of exemplary implementations of light pyrolysis oil 350 obtained from the steam cracking of light hydrocarbon gas streams.

[0046] Based on the total weight of the pyrolysis oil feed 102, the pyrolysis oil feed 102 may include 10% to 90% by weight of diluent 104. Based on the total hydrocarbon weight of diluent 104, diluent 104 may contain at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or even at least 99% by weight of aromatics having 6 to 8 carbon atoms. In an embodiment, the light aromatic stream is substantially composed of aromatics having 6 to 8 carbon atoms, such as benzene, toluene, xylene, and combinations thereof. Based on the total weight of the pyrolysis oil feed 102, the pyrolysis oil feed 102 may include 10% to 80% by weight, 10% to 70% by weight, 10% to 60% by weight, 10% to 40% by weight, 10% to 30% by weight, 10% to 20% by weight, 15% to 90% by weight, 15% to 75% by weight, 15% to 60% by weight, 15% to 45% by weight, 15% to 30% by weight, 15% to 25% by weight, or any subset thereof, of diluent 104. In an embodiment, heavy pyrolysis oil 250 may be mixed with diluent 104 (such as light pyrolysis oil 350) in a mixing unit (not shown) upstream of the first fixed-bed reactor 110 to produce the pyrolysis oil feed 102, which may then be passed to the first fixed-bed reactor 110. In an embodiment, the pyrolysis oil feed 102 may not include the diluent added to the heavy pyrolysis oil 250 upstream of the first fixed-bed reactor 110. However, in these embodiments, the pyrolysis oil feed 102 may still include toluene, xylene, or benzene that may be carried over from the process of producing heavy pyrolysis oil 250.

[0047] In one embodiment, the pyrolysis oil feed 102 may contain at least 50% by weight, such as at least 60% by weight, at least 70% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, 10% by weight to 100% by weight, 50% by weight to 100% by weight, 50% by weight to 99% by weight, 60% by weight to 99% by weight, 75% by weight to 99% by weight, 75% by weight to 90% by weight, 75% by weight to 85% by weight, or any subset thereof, of heavy pyrolysis oil 250. In another embodiment, the pyrolysis oil feed 102 may contain 75% by weight to 85% by weight of heavy pyrolysis oil 250 and 15% by weight to 25% by weight of diluent 104 (such as light pyrolysis oil 350). In an embodiment, the pyrolysis oil feed 102 may comprise 80% by weight of heavy pyrolysis oil 250 and 20% by weight of diluent 104, wherein diluent 104 comprises light pyrolysis oil 350, toluene, benzene, xylene, ethylbenzene, or a combination of these diluents. Based on the total weight of the pyrolysis oil in the pyrolysis oil feed, the pyrolysis oil feed 102 may comprise greater than or equal to 30% by weight (wt.%) of polycyclic aromatic hydrocarbons having greater than or equal to 16 carbon atoms, for example, greater than or equal to 35% by weight, greater than or equal to 40% by weight, greater than or equal to 40% by weight, greater than or equal to 45% by weight, or greater than or equal to 50% by weight of polycyclic aromatic hydrocarbons having greater than or equal to 16 carbon atoms.

[0048] In the implementation scheme, as determined by the test method in ASTM D5002, the density of the pyrolysis oil feed 102, comprising a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104, can be 0.98 g / cm³ at 15°C. 3 Up to 1.03 g / cm 3 For example, 0.98 g / cm 3 Up to 1.02 g / cm 3 1.00 g / cm 3 Up to 1.03 g / cm 3 Or 1.00 g / cm 3 Up to 1.02 g / cm 3In the implementation scheme, the dynamic viscosity of the pyrolysis oil feed 102, which comprises a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104, at 60°C may be 5 mPa*s to 10 mPa*s, greater than 5.0 mPa*s to less than 10.0 mPa*s, 5.0 mPa*s to 9.5 mPa*s, 5.0 mPa*s to 9.0 mPa*s, 5.5 mPa*s to 10.0 mPa*s, 5.5 mPa*s to 9.5 mPa*s, 5.5 mPa*s to 9.0 mPa*s, 6.0 mPa*s to 10.0 mPa*s, 6.0 mPa*s to 9.5 mPa*s, or 6.0 mPa*s to 9.0 mPa*s, wherein the dynamic viscosity is determined according to the test method in ASTM D7042. In the implementation scheme, as determined according to the test method in ASTM D7042, the kinematic viscosity of the pyrolysis oil feed 102, comprising a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104, at 60°C can be 5.0 mm. 2 / s to 10.0 mm 2 / s, for example, 5.0 mm 2 / s to 9.5 mm 2 / s, 5.0 mm 2 / s to 9.0 mm 2 / s, 5.5 mm 2 / s to 10 mm 2 / s, 5.5 mm 2 / s to 9.5 mm 2 / s, 5.5 mm 2 / s to 9.0 mm 2 / s, 6.0 mm 2 / s to 10.0 mm 2 / s, 6.0 mm 2 / s to 9.5 mm 2 / s or 6.0mm 2 / s to 9.0 mm 2 / s.

[0049] In the implementation scheme, the initial boiling point (IBP) of the pyrolysis oil feed 102, which contains a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104, may be 120°C to 150°C, for example, 120°C to 145°C, 125°C to 150°C, or 125°C to 145°C, as determined by the test method in ASTM D2887. In the implementation scheme, the final boiling point (FBP) of the pyrolysis oil feed 102, which comprises a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104, as determined by the test method in ASTM D2887, may be greater than or equal to 500°C, for example, greater than or equal to 600°C, greater than or equal to 650°C, greater than or equal to 700°C, 500°C to 1000°C, 500°C to 900°C, 500°C to 800°C, 600°C to 1000°C, 600°C to 900°C, 600°C to 800°C, 650°C to 1000°C, 650°C to 900°C, 650°C to 800°C, 700°C to 1000°C, 700°C to 900°C, or 700°C to 800°C. In the implementation scheme, the 50% boiling point temperature of the pyrolysis oil feed 102, which comprises a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104, as determined by the test method in ASTM D2887, may be 200°C to 300°C, 200°C to 290°C, 200°C to 275°C, 225°C to 300°C, 225°C to 290°C, 225°C to 275°C, 240°C to 300°C, 240°C to 290°C, or 240°C to 275°C.

[0050] The pyrolysis oil feed 102, comprising a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104, may also have a low concentration of sulfur and sulfur compounds. As determined according to the test methods in ASTM D2622, the concentration of sulfur and sulfur-containing compounds in the pyrolysis oil feed 102 comprising the mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104 may be less than or equal to 500 parts per million (ppmw), for example, less than or equal to 400 ppmw or even less than or equal to 300 ppmw. In embodiments, the concentration of sulfur and sulfur-containing compounds in the pyrolysis oil feed 102 comprising the mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104 may be greater than 0 (zero) ppmw to 500 ppmw, for example, 1 ppmw to 500 ppmw, 1 ppmw to 400 ppmw, or 1 ppmw to 300 ppmw. In the implementation, the pyrolysis oil feed 102, comprising a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104, may have a concentration of iron, nickel, or both less than or equal to 100 ppmw, less than or equal to 50 ppmw, less than or equal to 20 ppmw, or even less than or equal to 10 ppmw, for example, a concentration of iron, nickel, or both greater than or equal to 0 (zero) ppmw to less than or equal to 100 ppmw. Table 1 provides the properties of one embodiment of the pyrolysis oil feed 102 comprising a mixture of heavy pyrolysis oil 250 and light pyrolysis oil 350 as diluent 104. See again... Figure 1 In an embodiment, the pyrolysis oil feed 102 may further include a bottom recirculation stream 150 from a separation unit 140 located downstream of the second fixed-bed reactor 120.

[0051] Refer again Figure 2 The naphtha steam cracking system 200 may include a naphtha steam cracking unit 210 located upstream of a first fixed-bed reactor in system 100. The naphtha steam cracking unit 210 provides at least a portion of the pyrolysis oil feed 102. In an embodiment, a naphtha feed stream 204 may be fed to the naphtha steam cracking unit 210. The naphtha feed stream 204 may contain hydrocarbons within the naphtha distillation range, with boiling points ranging from 30°C to 225°C. The naphtha feed stream 204 may include hydrocarbons having 5 to 12 carbon atoms. Although... Figure 2This diagram illustrates one embodiment of a naphtha steam cracking unit 210, but other configurations of steam cracking units are also contemplated. The naphtha steam cracking unit 210 may include a convection zone 220 and a pyrolysis zone 222. A naphtha feed stream 204 may be passed along with steam 206 into the convection zone 220. In the convection zone 220, the mixture containing naphtha and steam may be preheated to a desired temperature. The contents of the convection zone 220 may then be passed to the pyrolysis zone 222, where the hydrocarbons from the naphtha feed stream 204 are steam cracked. The steam-cracked naphtha effluent stream 230 may exit the naphtha steam cracking unit 210 and pass through a separation unit 240. The steam-cracked naphtha effluent stream 230 may include a mixture of cracked hydrocarbon-based materials, which may be separated into one or more petrochemical products contained in one or more system product streams. The separation unit 240 can be any unit operation or multiple unit operations capable of separating heavy pyrolysis oil 250 from the gaseous stream 242. In an embodiment, the separation unit 240 can also be operated to separate at least one olefin product stream 244 from the gaseous stream 242 and the heavy pyrolysis oil 250. The heavy pyrolysis oil 250 may constitute all or part of the pyrolysis oil feed 102.

[0052] According to the implementation plan, pyrolysis zone 222 can operate at temperatures ranging from 750°C to 1000°C or from 800°C to 950°C. Pyrolysis zone 222 can operate with a residence time of 0.05 seconds to 2 seconds. The mass ratio of steam 206 to naphtha feed stream 204 can be from about 0.3:1 to about 2:1.

[0053] Now refer to Figure 3Heavy pyrolysis oil 250 from naphtha steam cracking system 200 can be combined with light pyrolysis oil 350 from gas steam cracking system 300 upstream of system 100. Naphtha steam cracking system 200 and gas steam cracking system 300 can operate in parallel and can both be located upstream of the first fixed-bed reactor of system 100. Naphtha steam cracking system 200 can have any of the features or characteristics of naphtha steam cracking system 200 previously discussed in this disclosure. Gas steam cracking system 300 may include gas steam cracking unit 310. In an embodiment, gas feed stream 304 can be passed to gas steam cracking unit 310. Gas feed stream 304 may contain hydrocarbons with a boiling point temperature less than or equal to 50°C or less than or equal to 30°C. Gas feed stream 304 may include hydrocarbons having less than or equal to 5 carbon atoms or less than or equal to 4 carbon atoms. Gas steam cracking unit 310 may include convection zone 320 and pyrolysis zone 322. Gas feed stream 304 may be passed together with steam 306 into convection zone 320. In convection zone 320, the mixture containing gas feed stream 304 and steam 306 may be preheated to a desired temperature. The contents of convection zone 320 may then be passed to pyrolysis zone 322, where they are steam cracked. Gas steam cracker effluent 330 may exit gas steam cracking unit 310 and pass through separation unit 340. Gas steam cracker effluent 330 may include a mixture of cracked hydrocarbon-based materials, which may be separated into one or more petrochemical products contained in one or more system product streams. Separation unit 340 may be any unit operation or multiple unit operations capable of separating gas steam cracker effluent 330 into light gas stream 342, at least one product stream 344, and light pyrolysis oil 350. In an embodiment, the at least one product stream 344 may be an olefin product stream. Light pyrolysis oil 350 can be combined with heavy pyrolysis oil 250 to form pyrolysis oil feed 102.

[0054] According to one or more embodiments, the pyrolysis zone 322 can operate at a temperature of 750°C to 1000°C or 800°C to 950°C. The pyrolysis zone 322 can operate with a residence time of 0.05 seconds to 2 seconds. The mass ratio of steam 306 to the gas feed stream 304 can be from about 0.3:1 to about 2:1. Although Figure 2 and Figure 3 Some embodiments represent naphtha steam cracking system 200 and gas steam cracking system 300, but other configurations of steam cracking units for producing heavy pyrolysis oil 250, light pyrolysis oil 350 or combinations thereof are also considered, such as, but not limited to, steam cracking systems for steam cracking crude oil, light hydrocarbon gas streams, condensate, atmospheric residue, vacuum distillation residue, vacuum gas oil or other heavy oils.

[0055] Refer again Figure 1The pyrolysis oil feed 102 can be fed to a first fixed-bed reactor 110. The first fixed-bed reactor 110 can operably contact the pyrolysis oil feed 102 with hydrogen 116 in the presence of a mixed metal oxide catalyst 112 to produce an intermediate stream 118. Contacting the pyrolysis oil feed 102 with hydrogen 116 in the presence of the mixed metal oxide catalyst 112 can convert at least a portion of the polycyclic aromatic hydrocarbons (PAHs) in the pyrolysis oil feed 102 into bicyclic aromatic hydrocarbons (BAHs), tricyclic aromatic hydrocarbons (BAHs), or both. The hydrogen 116 may include a stream of recycled hydrogen or supplemental hydrogen from an external hydrogen source inside or outside the refinery boundary. The hydrogen 116 can be fed directly to the first fixed-bed reactor 110 or combined with the pyrolysis oil feed 102 upstream of the first fixed-bed reactor 110. The hydrogen 116 can be used to pressurize the first fixed-bed reactor 110 to its operating pressure.

[0056] The first fixed-bed reactor 110 is a fixed-bed reactor. The fixed-bed reactor may include a packed bed of mixed metal oxide catalyst 112. Hydrogen may flow co-currently or counter-currently with the pyrolysis oil feed 102. In an embodiment, hydrogen may flow co-currently with the pyrolysis oil feed 102. For example, hydrogen may be entrained in the flowing pyrolysis oil feed 102, or it may permeate or bubble through the reaction bed as the pyrolysis oil feed 102 flows downward through the reaction bed. The fixed-bed reactor may be a continuous reactor. In an embodiment, the first fixed-bed reactor 110 may include one or more fixed-bed reactors. When the first fixed-bed reactor 110 includes multiple fixed-bed reactors, the multiple fixed-bed reactors may operate in series, in parallel, or in combination thereof. In an embodiment, the first fixed-bed reactor 110 may include multiple fixed-bed reactors connected in parallel.

[0057] The mixed metal oxide catalyst 112 may be catalytically active to convert polycyclic aromatic hydrocarbons having sixteen or more carbon atoms in the pyrolysis oil feed 102 into bicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons, or combinations thereof. The mixed metal oxide catalyst 112 may comprise a plurality of mixed metal oxide (MMO) particles. Each of the plurality of MMO particles may comprise a variety of different metal oxides. The various metal oxides of the MMO particles may include oxides of metals from Groups 3 to 13 of the International Union of Pure and Applied Chemistry (IUPAC) periodic table. In embodiments, the various metal oxides of the MMO particles may include combinations of oxides of iron, zirconium, cerium, aluminum, tungsten, molybdenum, and titanium. The MMO particles may also include metalloid oxides, such as oxides of silicon. The MMO particles may comprise oxides of metals or metalloids selected from iron oxide (Fe₂O₃), zirconium oxide (ZrO₂), cerium oxide (CeO₂), aluminum oxide (Al₂O₃), silicon dioxide (SiO₂), tungsten oxide (WO₃), molybdenum oxide (MoO₃), titanium oxide (TiO₂), and combinations thereof.

[0058] The MMO particles of the mixed metal oxide catalyst 112 may include iron oxide as one of a variety of metal oxides. In embodiments, the MMO particles may include 60 wt% to 95 wt% iron oxide, such as 70 wt% to 90 wt%, 75 wt% to 85 wt%, or 80 wt% to 85 wt% iron oxide. The MMO particles may include zirconium oxide as one of a variety of metal oxides. In embodiments, the MMO particles may include 1 wt% to 20 wt% zirconium oxide, such as 1 wt% to 15 wt%, 2.5 wt% to 12.5 wt%, or 5 wt% to 10 wt% zirconium oxide. The MMO particles may include cerium oxide as one of a variety of metal oxides. In embodiments, the MMO particles may include 0.1 wt% to 10 wt% cerium oxide, such as 0.5 wt% to 7.5 wt%, 0.5 wt% to 5 wt%, or 1 wt% to 5 wt% cerium oxide. The MMO particles may include aluminum oxide (alumina) as one of a variety of metal oxides. In an embodiment, the MMO particles may include 1% to 20% by weight of aluminum oxide (alumina), such as 2.5% to 15% by weight, 3% to 12.5% ​​by weight, or 5% to 10% by weight of aluminum oxide (alumina). The weight percentage of various metal oxides in the MMO particles is based on the total weight of the MMO particles. MMO particles may comprise 60 wt% to 95 wt% iron oxide, 1 wt% to 20 wt% zirconium oxide, 0.1 wt% to 10 wt% cerium oxide, and 1 wt% to 20 wt% aluminum oxide (alumina), or substantially comprise 60 wt% to 95 wt% iron oxide, 1 wt% to 20 wt% zirconium oxide, 0.1 wt% to 10 wt% cerium oxide, and 1 wt% to 20 wt% aluminum oxide (alumina), or substantially comprise 60 wt% to 95 wt% iron oxide, 1 wt% to 20 wt% zirconium oxide, 0.1 wt% to 10 wt% cerium oxide, and 1 wt% to 20 wt% aluminum oxide (alumina). In an embodiment, MMO particles may comprise 83 wt% iron oxide, 7.5 wt% zirconium oxide, 2.5 wt% cerium oxide, and 7.0 wt% aluminum oxide (alumina). In an embodiment, MMO particles do not include silicon dioxide. In this embodiment, MMO particles may comprise a variety of metal oxides mixed and melted or agglomerated together to form a homogeneous solid mixture of metal oxides rather than MMO particles deposited on the surface of a carrier material. MMO particles can be prepared by co-precipitation to obtain MMO particles containing a variety of different metal oxides, each of which is distributed throughout the entire MMO particle. After co-precipitation, the MMO particles can be pulverized to form a powder.

[0059] MMO particles may comprise nanoparticles having a maximum size of 20 nm to 200 nm, such as 20 nm to 175 nm, 20 nm to 150 nm, 20 nm to 125 nm, 20 nm to 100 nm, 20 nm to 75 nm, 20 nm to 50 nm, 20 nm to 40 nm, 20 nm to 30 nm, 25 nm to 200 nm, 30 nm to 200 nm, 40 nm to 200 nm, 50 nm to 200 nm, 75 nm to 200 nm, 100 nm to 200 nm, 125 nm to 200 nm, 150 nm to 200 nm, 175 nm to 200 nm, 50 nm to 175 nm, 75 nm to 150 nm, 100 nm to 125 nm, or any subset thereof. In embodiments, the MMO particles may be non-porous. Without being theoretically limited, it is believed that hydrocarbons may interact only with the surface of the MMO particles. Therefore, the increased surface area provided by the nanoparticle characteristics of mixed metal oxide catalysts can help achieve sufficient reaction rates.

[0060] MMO particles in powder form can be combined with other materials (including but not limited to binder materials, extrusion additives, or other materials), extruded, and calcined to form a mixed metal oxide catalyst 112 in the form of catalyst agglomerates. In an embodiment, MMO particles in powder form can be combined and mixed with binder materials and methylcellulose to form a solid mixture.

[0061] The binder material may comprise silica, alumina, silica-alumina, clay, or any combination thereof. Alumina may comprise acid-soluble alumina. Silica-alumina may comprise amorphous silica-alumina. Clay may include, but is not limited to, kaolin, montmorillonite, halloysite, bentonite, or combinations thereof. In an embodiment, the binder material may comprise bentonite, silica, or combinations thereof. In an embodiment, the mixed metal oxide catalyst 112 may comprise bentonite as a binder. Methylcellulose may be added to the solid mixture to facilitate extrusion, but may be burned off during calcination. Therefore, the mixed metal oxide catalyst 112 aggregates may comprise MMO particles and a binder, consist of MMO particles and a binder, or consist substantially of MMO particles and a binder.

[0062] The dry components, namely MMO particles, binder, and methylcellulose, can be thoroughly mixed to form a solid mixture. In an embodiment, the solid mixture may contain 50% to 90% by weight of MMO particles based on the total weight of the solid mixture, for example, 50% to 85% by weight, 50% to 80% by weight, 60% to 90% by weight, 60% to 85% by weight, 60% to 80% by weight, 65% to 90% by weight, 65% to 85% by weight, 65% to 80% by weight, 70% to 90% by weight, 70% to 85% by weight, 70% to 80% by weight, or about 75% by weight of MMO particles based on the total weight of the dry solid mixture. In an embodiment, the solid mixture may contain about 10% to 50% by weight of a binder based on the total weight of the dry solid mixture, such as 10% to 49.9% by weight, 10% to 40% by weight, 10% to 35% by weight, 10% to 30% by weight, 10% to 25% by weight, 15% to 50% by weight, 15% to 49.9% by weight, 15% to 40% by weight, 15% to 35% by weight, 15% to 30% by weight, 15% to 25% by weight, 20% to 50% by weight, 20% to 49.9% by weight, 20% to 40% by weight, 20% to 35% by weight, 20% to 30% by weight, 20% to 25% by weight, or 24% to 25% by weight of a binder based on the total weight of the dry solid mixture. In one embodiment, based on the total weight of the dry solids mixture, the solids mixture may contain 0.01 wt% to 2 wt% methylcellulose, for example, 0.01 wt% to 1 wt%, 0.1 wt% to 2 wt%, 0.1 wt% to 1 wt%, or about 0.1 wt% methylcellulose. In another embodiment, based on the total weight of the dry solids mixture, the dry mixture may contain about 75 wt% MMO particles, about 24.9 wt% binder material, and about 0.1 wt% methylcellulose.

[0063] Dry solid mixtures can be thoroughly mixed to form homogeneous solid mixtures, for example, by using a mortar and pestle, or by employing automated mixing equipment, such as, but not limited to, a V-type mixer, a Schugi mixer, or other powder mixing devices. After mixing, water can be added to the dry solid mixture to form an extrudable paste. In one embodiment, approximately 1.5 mL of water per gram of dry material can be added to the dry solid mixture to form an extrudable paste.

[0064] An extrudable paste comprising MMO particles, binder, methylcellulose, and water can then be extruded in an extruder. In one embodiment, the extrudable paste can be injected into the syringe of an injection pump. Alternatively, other pressurizing devices, such as peristaltic pumps, screw extruders, twin-screw extruders, etc., can be used to pressurize the paste. The pressurized paste can be extruded through an extrusion die to form an extrudate with an extruded strand. The extrusion die and the resulting extrudate can have a circular cross-section, or any other cross-sectional shape, such as star, square, hexagonal, trefoil, daisy, cylindrical, heptapod, or donut. The diameter of the extrusion die and the resulting extrudate can be from 1 mm to 3 mm, for example, 1.5 mm to 3 mm, 2.0 mm to 3 mm, 1 mm to 2.5 mm, 1.5 mm to 2.5 mm, 1.75 mm to 2.25 mm, or any subset thereof.

[0065] After extrusion, the extrudate can be dried and calcined. The extruded wire can be cut into lengths to form pellets before, after drying but before, or after calcination. Generally, it is preferable to dry the extruded wire or pellets before calcination because excess water in the catalyst particles during or after calcination can lead to the accumulation of vapor pressure and weaken or destroy the catalyst.

[0066] The extruded filaments or pellets may be dried at elevated temperatures. In embodiments, the extruded filaments or pellets may be dried at at least 40°C, for example, at least 50°C, 40°C to 100°C, 40°C to 90°C, 40°C to 80°C, 50°C to 70°C, or any subset thereof. The extruded filaments or pellets may be dried at elevated temperatures for at least 6 hours, for example, at least 12 hours, at least 18 hours, 6 hours to 48 hours, 12 hours to 48 hours, or any subset thereof.

[0067] After drying, the dried extruded filaments or pellets may subsequently be calcined. In an embodiment, the dried extruded filaments or pellets may be calcined at a temperature of at least 400°C, for example, at least 500°C, at least 600°C, 400°C to 800°C, 500°C to 700°C, 600°C to 700°C, 625°C to 675°C, or any subset thereof. The dried filaments or pellets may be calcined for at least 1 hour, for example, at least 1.5 hours, 1 hour to 5 hours, 1 hour to 3 hours, 1.5 hours to 2.5 hours, or any subset thereof. The calcination atmosphere may include an oxygen-containing gas, such as air. If not treated before calcination, the calcined filaments may be crushed and sieved to obtain a mixed metal oxide catalyst 112 in pellet form.

[0068] The agglomerates of the mixed metal oxide catalyst may comprise MMO particles and a binder. The agglomerates of the mixed metal oxide catalyst may also comprise any calcination residue from methylcellulose. Each MMO particle comprises Fe2O3, ZrO2, CeO2, and Al2O3. In embodiments, based on the total weight of the mixed metal oxide catalyst, the agglomerates of the mixed metal oxide catalyst may comprise 65 wt% to 85 wt%, 65 wt% to 80 wt%, 70 wt% to 85 wt%, 70 wt% to 80 wt%, 75 wt% to 85 wt%, 75 wt% to 80 wt%, 80 wt% to 85 wt%, or about 75 wt% of MMO particles, with the balance being binder material and any calcination residue from methylcellulose. In an embodiment, based on the total weight of the mixed metal oxide catalyst, the mixed metal oxide catalyst may contain 15 wt% to 35 wt%, 15 wt% to 30 wt%, 15 wt% to 25 wt%, 20 wt% to 35 wt%, 20 wt% to 30 wt%, 20 wt% to 25 wt%, 25 wt% to 35 wt%, 25 wt% to 30 wt%, or about 25 wt% of binder material. Based on the total weight of the mixed metal oxide catalyst, the concentration of methylcellulose residue in the mixed metal oxide catalyst may be less than 0.1 wt%, less than 0.05 wt%, or even less than or equal to 0.01 wt%. In an embodiment, based on the total weight of the mixed metal oxide catalyst, the agglomerates of the mixed metal oxide catalyst may contain at least 80 wt%, at least 90 wt%, or at least 95 wt%, at least 99 wt%, or even at least 99.9 wt% of Fe2O3, ZrO2, CeO2, and Al2O3, as well as binder material. In the implementation scheme, the mixed metal oxide catalyst may comprise 75% by weight of MMO particles and 25% by weight of binder material.

[0069] The agglomerates of the mixed metal oxide catalyst 112 may have agglomerate diameters of, for example, 1 mm to 3 mm, 1.5 mm to 3 mm, 1 mm to 2.5 mm, 1.5 mm to 2.5 mm, or any subset thereof. In an embodiment, the agglomerates of the mixed metal oxide catalyst 112 may be cylindrical, having agglomerate diameter and agglomerate length. The agglomerate length may be from about 2 mm to about 4 mm.

[0070] Refer again Figure 1Under the reaction conditions in the first fixed-bed reactor 110, in the presence of a mixed metal oxide catalyst 112, contacting the pyrolysis oil feed 102 with hydrogen 116 can convert at least a portion of the polycyclic aromatic hydrocarbons (PAHs) in the pyrolysis oil feed 102 into bicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons, or both in a single step without subsequent chemical reaction steps. Converting at least a portion of a PAH into a lighter aromatic compound comprising bicyclic, tricyclic, or both is a complex reaction scheme involving multiple simultaneous and selective reactions, which may include selective hydrogenation of one aromatic ring, but not all, of the compound, followed by ring-opening, hydrodealkylation, alkyl transfer, and disproportionation reactions of the saturated tetracyclic aromatic compound. Without being bound by any particular theory, it is believed that upgrading the pyrolysis oil feed 102 may include selective hydrogenation of at least one aromatic ring structure or PAH to produce a molecule having one or more aromatic rings and at least one saturated ring. The saturated ring portion may then undergo ring-opening to generate a substituted aromatic compound. The substituted aromatic compounds may then undergo one or more of the following reactions: hydroalkylation, alkyl transfer, or disproportionation, to generate monocyclic, bicyclic, and / or tricyclic aromatic compounds. It should be understood that these reactions, along with other chemical reactions, may undergo various variations and combinations during the upgrading process. This complex sequence of simultaneous reactions used for upgrading pyrolysis oil feed 102 can be catalyzed using a mixed metal oxide catalyst 112.

[0071] The first fixed-bed reactor 110 can contact the pyrolysis oil feed 102 with hydrogen 116 in the presence of a mixed metal oxide catalyst 112, under mild operating conditions sufficient to upgrade at least a portion of the polycyclic aromatic hydrocarbons in the pyrolysis oil feed 102 to produce an intermediate stream 118, wherein the intermediate stream 118 comprises bicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons, or both. The first fixed-bed reactor 110 can be operated at temperatures ranging from 300°C to 500°C, for example, 350°C to 500°C, 400°C to 500°C, 300°C to 450°C, 350°C to 450°C, or 400°C to 450°C. The first fixed-bed reactor 110 can operate at operating pressures from 1 MPa (10 bar) to 20 MPa (200 bar), for example, 3 MPa (30 bar) to 20 MPa (200 bar), 5 MPa (50 bar) to 20 MPa (200 bar), 7 MPa (70 bar) to 20 MPa (200 bar), 10 MPa (100 bar) to 20 MPa (200 bar), 12 MPa (120 bar) to 18 MPa (180 bar), 14 MPa (140 bar) to 16 MPa (160 bar), 1 MPa (10 bar) to 15 MPa (150 bar), 3 MPa (30 bar) to 15 MPa (150 bar), 5 MPa (50 bar) to 15 MPa (150 bar), 7 MPa (70 bar) to 15 MPa (150 bar), or 10 MPa (100 bar) to 15 MPa (150 bar). MPa (150 bar). The first fixed-bed reactor 110 can be operated under a hydrogen 116 to pyrolysis oil feed 102 volume ratio of 500 to 1500, 500 to 1400, 500 to 1300, 500 to 1200, 800 to 1500, 800 to 1400, 800 to 1300, or 800 to 1200. The first fixed-bed reactor 110 can be operated at 0.1 h -1 Up to 1.2h -1 0.1h -1 Up to 1 hour -1 0.1h -1 up to 0.8h -1 0.1 h -1 up to 0.6h -1 0.2 h -1 up to 0.4h -1 Or any subset thereof, at a liquid time space velocity (LHSV). The first fixed-bed reactor 110 can operate at 200 h⁻¹. -1 Up to 1500h -1 Operating at atmospheric hourly space velocity (GHSV), for example, 200 h. -1 Up to 1200h -1 400h -1Up to 1200h -1 600h -1 Up to 1000h -1 700 h -1 Up to 900h -1 Or operate at air space velocity (GHSV) of any subset thereof.

[0072] Reference Figure 2 Intermediate stream 118 may include bicyclic aromatic compounds. Compared to pyrolysis oil feed 102, intermediate stream 118 may include a larger percentage of bicyclic aromatic compounds containing 10 to 18 carbon atoms. Based on the total weight of intermediate stream 118, intermediate stream 118 may include at least 35%, at least 40%, at least 45%, at least 50%, or even at least 55% by weight of bicyclic aromatic compounds (C10 to C18 aromatic compounds) having 10 to 18 carbon atoms, including any C10 to C18 aromatic compounds added to pyrolysis oil feed 102 and passing through diluent 104 in the first fixed-bed reactor 110. In addition to bicyclic aromatic compounds, intermediate stream 118 may also include other components, such as, but not limited to, unreacted hydrogen, unreacted pyrolysis oil components, light hydrocarbon gases, light aromatic compounds having 6 to 8 carbon atoms, tricyclic aromatic compounds, and combinations thereof. The bicyclic aromatic compounds included in intermediate stream 118 can be transferred to a second fixed-bed reactor 120, where they are then hydrocracking to produce BTEX. The second fixed-bed reactor 120 can increase the yield of BTEX and reduce the amount of unreacted pyrolysis oil recycled back into the process.

[0073] Now for reference Figure 5 In one embodiment, the first fixed-bed reactor 110 may include a mixed metal oxide catalyst 112 and a secondary catalyst 114. Within the first fixed-bed reactor 110, the mixed metal oxide catalyst 112 may be located in a different bed from the secondary catalyst 114. The mixed metal oxide catalyst 112 may be positioned upstream of the secondary catalyst 114. Upon passing through the first fixed-bed reactor 110, the pyrolysis oil feed 102 may encounter the mixed metal oxide catalyst 112 in the first bed and subsequently the secondary catalyst 114 in the second bed.

[0074] Secondary catalyst 114 may contain metal atoms, including aluminum atoms, silicon atoms, zirconium atoms, nickel atoms, tungsten atoms, or combinations thereof. In embodiments, the metal atoms may be present in oxide form (Al₂O₃, SiO₂, ZrO₂, NiO, and WO₃). In embodiments, secondary catalyst 114 may contain 18.5 wt% to 21.5 wt% Al₂O₃. In embodiments, secondary catalyst 114 may contain 36.5 wt% to 39.5 wt% SiO₂. In embodiments, secondary catalyst 114 may contain 9.2 wt% to 10.2 wt% ZrO₂. In embodiments, secondary catalyst 114 may contain 10.5 wt% to 11.5 wt% NiO. In embodiments, secondary catalyst 114 may contain 18.5 wt% to 21.5 wt% WO₃. In an embodiment, the secondary catalyst 114 may comprise 18.5 wt% to 21.5 wt% Al2O3, 36.5 wt% to 39.5 wt% SiO2, 9.2 wt% to 10.2 wt% ZrO2, 10.5 wt% to 11.5 wt% NiO, and 18.5 wt% to 21.5 wt% WO3. The weight percentages of the secondary catalyst components are calculated based on the total weight of the secondary catalyst. The pyrolysis oil feed 102 can enter a first fixed-bed reactor 110. Within the first fixed-bed reactor 110, the pyrolysis oil feed 102 can be contacted with a mixed metal oxide catalyst 112 in the presence of hydrogen 116, converting at least a portion of the pyrolysis oil feed 102. The resulting reaction products and unconverted pyrolysis oil feed can then be contacted with a secondary catalyst 114 in the first fixed-bed reactor 110 in the presence of hydrogen 116. In an embodiment, the conditions under which the pyrolysis oil feed 102 contacts each of the mixed metal oxide catalyst 112 and the secondary catalyst 114 are substantially the same.

[0075] The first fixed-bed reactor 110 can contact the pyrolysis oil feed 102 with hydrogen 116 in the presence of a mixed metal oxide catalyst 112 and then a secondary catalyst 114 downstream of the mixed metal oxide catalyst 112, under mild operating conditions sufficient to upgrade at least a portion of the polycyclic aromatic hydrocarbons in the pyrolysis oil feed 102 to produce an intermediate stream 118, wherein the intermediate stream 118 comprises bicyclic aromatic hydrocarbons and / or tricyclic aromatic hydrocarbons. The first fixed-bed reactor 110 can be operated at an operating temperature in the range of 300 degrees Celsius (°C) to 500°C, for example at operating temperatures of 350°C to 500°C, 400°C to 500°C, 300°C to 450°C, 350°C to 450°C, or 400°C to 450°C. The first fixed-bed reactor 110 can operate at operating pressures from 1 MPa (10 bar) to 20 MPa (200 bar), for example at 3 MPa (30 bar) to 20 MPa (200 bar), 5 MPa (50 bar) to 20 MPa (200 bar), 7 MPa (70 bar) to 20 MPa (200 bar), 10 MPa (100 bar) to 20 MPa (200 bar), 12 MPa (120 bar) to 18 MPa (180 bar), 14 MPa (140 bar) to 16 MPa (160 bar), 1 MPa (10 bar) to 15 MPa (150 bar), 3 MPa (30 bar) to 15 MPa (150 bar), 5 MPa (50 bar) to 15 MPa (150 bar), 7 MPa (70 bar) to 15 MPa (150 bar) or 10 MPa The first fixed-bed reactor 110 can operate at an operating pressure of 100 bar to 15 MPa (150 bar). The first fixed-bed reactor 110 can operate with a hydrogen to pyrolysis oil feed 102 volume ratio of 500 to 1500, 500 to 1400, 500 to 1300, 500 to 1200, 800 to 1500, 800 to 1400, 800 to 1300, or 800 to 1200. The first fixed-bed reactor 110 can operate for 0.1 h... -1 Up to 1.2h -1 0.1h -1 Up to 1 hour -1 0.1h -1 up to 0.8h -1 0.1 h -1 up to 0.6h -1 0.2 h -1 up to 0.4h -1 Or any subset thereof, at a liquid time space velocity (LHSV). The first fixed-bed reactor 110 can operate at 200 h⁻¹. -1 Up to 1500h -1 Operating at air space velocity (GHSV), for example at 200 h.-1 Up to 1200h -1 400h -1 Up to 1200h -1 600 h -1 Up to 1000h -1 Or operate at air space velocity (GHSV) of any subset thereof.

[0076] Now refer to Figure 6 The first fixed-bed reactor 110 can contact the pyrolysis oil feed 102 with hydrogen 116 in the presence of a secondary catalyst 114 and then a mixed metal oxide catalyst 112 downstream of the secondary catalyst 114, under mild operating conditions sufficient to upgrade at least a portion of the polycyclic aromatic hydrocarbons in the pyrolysis oil feed 102 to produce an intermediate stream 118, wherein the intermediate stream 118 comprises bicyclic aromatic hydrocarbons and / or tricyclic aromatic hydrocarbons. The first fixed-bed reactor 110 can be operated at an operating temperature in the range of 300 degrees Celsius (°C) to 500°C, for example, 350°C to 500°C, 400°C to 500°C, 300°C to 450°C, 350°C to 450°C, or 400°C to 450°C. The first fixed-bed reactor 110 can operate at operating pressures from 1 MPa (10 bar) to 20 MPa (200 bar), for example, 3 MPa (30 bar) to 20 MPa (200 bar), 5 MPa (50 bar) to 20 MPa (200 bar), 7 MPa (70 bar) to 20 MPa (200 bar), 10 MPa (100 bar) to 20 MPa (200 bar), 12 MPa (120 bar) to 18 MPa (180 bar), 14 MPa (140 bar) to 16 MPa (160 bar), 1 MPa (10 bar) to 15 MPa (150 bar), 3 MPa (30 bar) to 15 MPa (150 bar), 5 MPa (50 bar) to 15 MPa (150 bar), 7 MPa (70 bar) to 15 MPa (150 bar), or 10 MPa (100 bar) to 15 MPa (150 bar). The first fixed-bed reactor 110 can operate at an operating pressure of MPa (150 bar). The hydrogen to pyrolysis oil feed 102 volume ratio can be 500 to 1500, 500 to 1400, 500 to 1300, 500 to 1200, 800 to 1500, 800 to 1400, 800 to 1300, or 800 to 1200. The first fixed-bed reactor 110 can operate for 0.1 h... -1 Up to 1 hour -1 0.1h -1 up to 0.8h -1 0.1h -1 up to 0.6h -1 0.2 h-1 up to 0.4h -1 Or any subset thereof, at a liquid time hourly space velocity (LHSV). The first fixed-bed reactor 110 can operate at 200 h⁻¹. -1 Up to 1500 h -1 Operating at atmospheric hourly space velocity (GHSV), for example, 200 h -1 Up to 1200 h -1 400 h -1 Up to 1200 h -1 600 h -1 Up to 1000 h -1 Or operate at air space velocity (GHSV) of any subset thereof.

[0077] Refer again Figure 1 Intermediate stream 118 can be passed downstream of the first fixed-bed reactor 110 to the second fixed-bed reactor 120. In an embodiment, intermediate stream 118 can be passed directly from the first fixed-bed reactor 110 to the second fixed-bed reactor 120 without any intervention unit operation that causes a chemical reaction or isolates one or more components of intermediate stream 118. The second fixed-bed reactor 120 can be operably contacted with hydrogen 124 in the presence of a mesoporous supported metal catalyst 122 to produce second reactor effluent 130. Contacting intermediate stream 118 with hydrogen 124 in the presence of the mesoporous supported metal catalyst 122 can cause at least a portion of the bicyclic aromatic compounds and / or triaromatic compounds in intermediate stream 118 to react to form aromatic compounds having six to eight carbon atoms. Unreacted hydrogen can be passed from the first fixed-bed reactor 110 to the second fixed-bed reactor 120 as part of intermediate stream 118. Hydrogen 124 may be additionally added to the second fixed-bed reactor 120. Hydrogen 124 may include a recirculated hydrogen stream or supplemental hydrogen from an external hydrogen source inside or outside the refinery boundary. Hydrogen 124 may be directly supplied to the second fixed-bed reactor 120, or it may be combined with the intermediate stream 118 upstream of the second fixed-bed reactor 120. Hydrogen 124 may be used to pressurize the second fixed-bed reactor 120 to its operating pressure.

[0078] The second fixed-bed reactor 120 is a fixed-bed reactor. The fixed-bed reactor may include a mesoporous supported metal catalyst 122 in a packed bed. Hydrogen may flow in parallel with the intermediate stream 118. In some embodiments, hydrogen may permeate or bubble through the packed bed. In embodiments, the second fixed-bed reactor 120 may comprise one or more fixed-bed reactors. When the second fixed-bed reactor 120 comprises multiple fixed-bed reactors, the multiple fixed-bed reactors may operate in series, in parallel, or in combination thereof.

[0079] The mesoporous supported metal catalyst 122 can operatively cause at least a portion of the bicyclic aromatic compounds and / or triaromatic compounds in the intermediate stream 118 to react to form an aromatic compound (BTEX) having six to eight carbon atoms. The mesoporous supported metal catalyst 122 may include a first metal catalyst, a second metal catalyst, and a mesoporous support. The mesoporous support may include a zeolite support component.

[0080] The zeolite support component may comprise ultrastable UY (USY) zeolite, β-zeolite, or both. The β-zeolite may be nano-sized. The zeolite support component may comprise USY zeolite and β-zeolite in a ratio of 1:1 to 2:1. In embodiments, the zeolite support component may comprise USY zeolite and β-zeolite in ratios of 1.25:1 to 2:1, 1.4:1 to 2:1, 1.45:1 to 2:1, 1:1 to 1.75:1, 1:1 to 1.6:1, 1:1 to 1.55:1, 1.25:1 to 1.75:1, 1.4:1 to 1.6:1, 1.45:1 to 1.55:1, or any subset thereof. In embodiments, the zeolite support component may comprise USY zeolite and β-zeolite in a ratio of approximately 3:2.

[0081] The zeolite support component may have an average pore size sufficient to allow polycyclic aromatic hydrocarbons to enter the reaction sites within the pores of the zeolite support component. As determined using the Barrett-Joyner-Halenda (BJH) method, the average pore size of the zeolite support component may be greater than or equal to 2 nanometers (nm), greater than or equal to 3 nm, or greater than or equal to 4 nm. As determined using the BJH method, the average pore size of the zeolite support component may be less than or equal to 40 nm, less than or equal to 30 nm, or even less than or equal to 25 nm. In embodiments, the average pore size of the zeolite support component may be 2 nm to 40 nm, 2 nm to 30 nm, 2 nm to 25 nm, 5 nm to 40 nm, 5 nm to 30 nm, 5 nm to 25 nm, 8 nm to 40 nm, 8 nm to 30 nm, or 8 nm to 25 nm, 3 nm to 6 nm, or any subset thereof, wherein the average pore size is determined using the BJH method. In embodiments, the zeolite support component may have an average pore size of 3 nm to 6 nm. The pore size of the zeolite carrier component can be suitable for USY zeolite, β zeolite, or both.

[0082] The molar ratio of silica (SiO2) to alumina (Al2O3) in the zeolite support component can be greater than or equal to 10, for example, greater than or equal to 20, 30, 40, 50, or 60. The molar ratio of SiO2 to Al2O3 in the zeolite support component can be less than or equal to 70, for example, less than or equal to 60, 50, 40, 30, or even less than or equal to 20. The molar ratio of SiO2 to Al2O3 in the zeolite support component can range from 10 to 70. In the embodiments, the molar ratio of SiO2 to Al2O3 in the zeolite support component can be 10 to 60, 10 to 50, 10 to 40, 20 to 70, 20 to 60, 20 to 50, 20 to 40, 30 to 70, 30 to 60, 30 to 50, 40 to 70, 40 to 60, 50 to 70, or 10 to 30. The molar ratio of silica to alumina in the zeolite support component can be suitable for USY zeolite, β-zeolite, or both.

[0083] The zeolite support component may comprise particles, and the average diameter of the particles, as measured by their longest dimension, may be from 2000 nm to 5000 nm. In embodiments, the average diameter of the zeolite support component particles, as measured by their longest dimension, may be 2000 nm to 4500 nm, 2000 nm to 4000 nm, 2000 nm to 3500 nm, 2000 nm to 3000 nm, 2000 nm to 2500 nm, 2500 nm to 5000 nm, 3000 nm to 5000 nm, 3500 nm to 5000 nm, 4000 nm to 5000 nm, 4500 nm to 5000 nm, 2500 nm to 4500 nm, 3000 nm to 4000 nm, or any subset thereof. In embodiments, the microporous zeolite particles exist in a single-crystal structure. The particle size of the zeolite support component may be suitable for USY zeolite, β-zeolite, or both.

[0084] The average surface area of ​​the zeolite carrier component can be at least 400 m². 2 / g. In the implementation scheme, the average surface area of ​​the zeolite carrier component may be at least 425m². 2 / g、400m 2 / g to 450m 2 / g、400m 2 / g to 440m 2 / g、400 m 2 / g to 430m 2 / g、400m 2 / g to 420m 2 / g、410m 2 / g to 450m 2 / g、420m 2 / g to 450 m 2 / g、430m 2 / g to 45m 2 / g、410m 2 / g to 440m 2 / g、420m 2 / g to 430m 2 / g or any subset thereof. Surface area can be measured according to the Brunauer-Emmett-Teller (BET) method. The surface area of ​​the zeolite carrier component can be applied to USY zeolite, β zeolite, or both.

[0085] If determined using the BJH method, the average pore volume of the zeolite support component can be from 0.3 ml / g to 0.6 ml / g. In embodiments, the average pore volume of the zeolite support component can be from 0.3 ml / g to 0.5 ml / g, 0.3 ml / g to 0.4 ml / g, 0.4 ml / g to 0.6 ml / g, 0.5 ml / g to 0.6 ml / g, 0.4 ml / g to 0.5 ml / g, or any subset thereof. The pore volume of the zeolite support component can be applicable to USY zeolite, β-zeolite, or both.

[0086] In addition to zeolite carrier components, mesoporous carriers may also contain binders and macroporous alumina.

[0087] The binder may comprise alumina, such as acid-soluble alumina; clay; or amorphous silica-alumina. In embodiments, the binder may comprise acid-soluble alumina. Suitable acid-soluble alumina for use as a binder is commercially available from Sasol Inc., under the trade name CATAPAL B.

[0088] As measured by BET, the average surface area of ​​macroporous alumina can be at least 100 m². 2 / g. In the implementation scheme, the average surface area of ​​macroporous alumina can be at least 125m². 2 / g, at least 150m 2 / g, 100m 2 / g to 300m 2 / g、125m 2 / g to 300m 2 / g, 150m 2 / g or any subset thereof. The average BJH pore radius of the macroporous alumina may be at least 5 nm. In embodiments, the average BJH pore radius of the macroporous alumina may be at least 8 nm, at least 10 nm, at least 11 nm, 5 nm to 20 nm, 8 nm to 20 nm, 10 nm to 20 nm, 11 nm to 20 nm or any subset thereof. The average BJH pore volume of the macroporous alumina may be from 0.8 ml / g to 1.1 ml / g, for example 0.9 ml / g to 1.1 ml / g, 1.0 ml / g to 1.1 ml / g, 0.8 ml / g to 1.0 ml / g, 0.8 ml / g to 0.9 ml / g, 0.9 ml / g to 1.0 ml / g.

[0089] The mesoporous support can be extruded into agglomerates. The agglomerates can then be impregnated with a first metal catalyst and a second metal catalyst to prepare a mesoporous supported metal catalyst 122.

[0090] Agglomerates can be formed by first preparing a binder paste. The binder paste can then be mixed with dry catalyst components (zeolite and macroporous alumina) to form a carrier paste. The carrier paste can be extruded to form a carrier extrudate. The carrier extrudate can be dried, calcined, and impregnated with a first metal catalyst (Ni) and a second metal catalyst (W).

[0091] A binder paste can be formed by mixing an acid (such as nitric acid) with alumina binder particles. The binder paste can be homogeneous, without large visible particles. The binder paste can then be mixed with macroporous alumina, USY zeolite, and nano-β zeolite to form a carrier paste. The carrier paste can then be extruded to form a carrier extrudate with a diameter of approximately 1 mm to 2 mm. The carrier extrudate can then be dried, for example, at approximately 110 °C for at least 12 hours. The dried carrier extrudate can then be calcined in air at a heating rate of approximately 2 °C / min to approximately 550 °C for at least 4 hours. Before or after calcination, the carrier extrudate can be cut or broken into granules with a length of approximately 2 mm to 4 mm. The carrier extrudate can have a circular cross-section or any other cross-sectional shape, such as star-shaped, square, hexagonal, trefoil-shaped, daisy-shaped, cylindrical, heptapod-shaped, or donut-shaped.

[0092] The mesoporous supported metal catalyst 122 can be prepared from the mesoporous support by wet impregnating at least a first metal catalyst precursor and a second metal catalyst precursor onto the outer surface, pore surface, or both of the mesoporous support. Wet impregnation of the first and second metal catalysts onto the mesoporous support may include preparing an aqueous metal solution comprising the first and second metal catalysts. The first and second metal catalysts may be introduced into water in their hydrated form (e.g., ammonium metatungstate (NH4)). 10 (H2W 12O 42 (xH2O and nickel nitrate hexahydrate Ni(NO3)2). The dried and calcined zeolite particles can be immersed in a molten metal for a sufficient time to impregnate them with the metal, for example, at least 3 hours. The impregnated zeolite particles can be dried again, for example, at 110°C for 12 hours. The dried and impregnated zeolite particles can be calcined again, for example, at about 500°C for about 4 hours (heating rate about 2°C / min). The dried and impregnated zeolite particles can then be calcined in air. The calcined and impregnated zeolite particles thus form a mesoporous supported metal catalyst 122 suitable for fixed-bed reactors.

[0093] The mesoporous supported metal catalyst 122 may contain 40 wt% to 60 wt% of a zeolite support component. In an embodiment, based on the total weight of the mesoporous supported metal catalyst 122, the mesoporous supported metal catalyst may contain 40 wt% to 55 wt%, 40 wt% to 50 wt%, 45 wt% to 60 wt%, 50 wt% to 60 wt%, 45 wt% to 55 wt% or any subset thereof of total zeolite, including nano-β zeolite and Y-type zeolite.

[0094] Based on the total weight of the mesoporous supported metal catalyst 122, the mesoporous supported metal catalyst 122 may contain 10 wt% to 20 wt%, 12.5 wt% to 20 wt%, 15 wt% to 20 wt%, 17.5 wt% to 20 wt%, 10 wt% to 17.5 wt%, 10 wt% to 15 wt%, 10 wt% to 12.5 wt%, 12.5 wt% to 17.5 wt%, or any subset thereof, of a binder.

[0095] The mesoporous supported metal catalyst 122 may comprise 2 wt% to 10 wt% macroporous alumina. In embodiments, the mesoporous supported metal catalyst 122 may comprise 2 wt% to 8 wt%, 2 wt% to 6 wt%, 2 wt% to 4 wt%, 4 wt% to 10 wt%, 6 wt% to 10 wt%, 8 wt% to 10 wt%, 4 wt% to 8 wt%, or any subset thereof macroporous alumina. As previously mentioned, the mesoporous supported metal catalyst 122 may comprise a first metal catalyst and a second metal catalyst supported on mesopores. The first metal catalyst may be a nickel catalyst. The nickel catalyst may be present in the form of nickel oxide (NiO). In embodiments, based on the total weight of the mesoporous supported metal catalyst 122, the mesoporous supported metal catalyst may comprise 4 wt% to 8 wt%, 6 wt% to 8 wt%, 4 wt% to 6 wt%, 5 wt% to 7 wt%, or any subset thereof first metal catalyst.

[0096] The second metal catalyst may be a tungsten catalyst. The tungsten catalyst may exist in the form of tungsten oxide (WO3). Based on the total weight of the mesoporous supported metal catalyst 122, the mesoporous supported metal catalyst 122 may contain 20 wt% to 30 wt%, 22 wt% to 30 wt%, 24 wt% to 30 wt%, 26 wt% to 30 wt%, 28 wt% to 30 wt%, 20 wt% to 28 wt%, 20 wt% to 26 wt%, 20 wt% to 24 wt%, 20 wt% to 22 wt%, 22 wt% to 28 wt%, 24 wt% to 26 wt%, or any subset thereof of the second metal catalyst.

[0097] As measured by BET, the surface area of ​​the mesoporous supported metal catalyst 122 can be 200 m². 2 / g to 400m 2 / g. In the implementation scheme, the surface area of ​​the mesoporous supported metal catalyst 122 can be 200m², as measured by BET. 2 / g to 350m 2 / g、200m 2 / g to 300m 2 / g、200m 2 / g to 250m 2 / g、250m 2 / g to 400m 2 / g、300m 2 / g to 400m 2 / g, 350m 2 / g to 400m 2 / g、250m 2 / g to 350m 2 / g or any subset thereof. The pore volume of the mesoporous supported metal catalyst 122 can be from 0.4 ml / g to 0.7 ml / g. In embodiments, the pore volume of the mesoporous supported metal catalyst 122 can be from 0.4 ml / g to 0.6 ml / g, 0.4 ml / g to 0.5 ml / g, 0.5 ml / g to 0.7 ml / g, 0.6 ml / g to 0.7 ml / g, 0.5 ml / g to 0.6 ml / g, or any subset thereof. The average pore size of the mesoporous supported metal catalyst 122 can be from 6 nm to 10 nm. In embodiments, the average pore size of the mesoporous supported metal catalyst 122 can be from 6 nm to 9 nm, 6 nm to 8 nm, 6 nm to 7 nm, 7 nm to 10 nm, 8 nm to 10 nm, 9 nm to 10 nm, 7 nm to 9 nm, or any subset thereof.

[0098] Refer again Figure 1In the presence of a mesoporous supported metal catalyst 122, contacting intermediate stream 118 with hydrogen 124 under reaction conditions can cause at least a portion of the bicyclic aromatic compounds, tricyclic aromatic compounds, or both in intermediate stream 118 to react in a single step to form a light aromatic compound having six to eight carbon atoms, without subsequent chemical reaction steps. Converting at least a portion of the bicyclic and / or tricyclic aromatic compounds in the intermediate stream into an aromatic compound having six to eight carbon atoms is also a complex reaction scheme involving multiple simultaneous and selective reactions, which may include selective hydrogenation of one aromatic ring, but not all, of the compound, followed by ring-opening, hydrodealkylation, alkyl transfer, and disproportionation reactions of the saturated cycloalkane ring. Without being bound by any particular theory, it is believed that upgrading intermediate stream 118 may include selective hydrogenation of at least one aromatic ring structure of a polycyclic aromatic compound, such as the bicyclic aromatic compound in intermediate stream 118, to produce a molecule having one aromatic ring and at least one saturated ring. The saturated ring may then undergo ring-opening to generate a substituted aromatic compound. The substituted aromatic compounds can then undergo one or more of the following reactions: hydroalkylation, alkyl transfer, or disproportionation, to produce aromatic compounds with 6 to 8 carbon atoms, such as BTEX. It should be understood that these reactions, along with other chemical reactions, can undergo various variations and combinations in the upgrading process within the second fixed-bed reactor 120. This complex simultaneous reaction sequence for the upgrading intermediate stream 118 can be catalyzed using a mesoporous supported metal catalyst 122.

[0099] The second fixed-bed reactor 120 can contact the intermediate stream 118 with hydrogen 124 in the presence of a mesoporous supported metal catalyst 122, under mild operating conditions sufficient to cause at least a portion of the bicyclic aromatic compounds and / or triaromatic compounds in the intermediate stream 118 to react to form aromatic compounds having six to eight carbon atoms. The second fixed-bed reactor 110 can be operated at an operating temperature in the range of 300°C to 500°C, for example, 350°C to 500°C, 400°C to 500°C, 300°C to 450°C, 350°C to 450°C, or 400°C to 450°C. The second fixed-bed reactor 120 can operate at an operating pressure of 1 MPa (10 bar) to 20 MPa (200 bar), for example, 3 MPa (30 bar) to 20 MPa (200 bar), 5 MPa (50 bar) to 20 MPa (200 bar), 7 MPa (70 bar) to 20 MPa (200 bar), 10 MPa (100 bar) to 20 MPa (200 bar), 1 MPa (10 bar) to 15 MPa (150 bar), 3 MPa (30 bar) to 15 MPa (150 bar), 5 MPa (50 bar) to 15 MPa (150 bar), 7 MPa (70 bar) to 15 MPa (150 bar), or 10 MPa (100 bar) to 15 MPa (150 bar). The second fixed-bed reactor 120 can operate at an operating pressure of 0.3 h. - ¹ to 1.5 h - ¹ Operation under LHSV, for example, 0.5 h - ¹ to 1.5 h - ¹、0.9 h - ¹ to 1.4 h - ¹、0.9 h - ¹ to 1.3 h - ¹、0.9 h - ¹ to 1.2 h - ¹、1.0 h - ¹ to 1.5 h - ¹、1.1 h - ¹ to 1.5 h - ¹、1.2 h - ¹ to 1.5 h - ¹、1.0 h - ¹ to 1.4 h - ¹、1.1 h - ¹ to 1.3 h - ¹ or any subset thereof, operated under LHSV. The second fixed-bed reactor 120 can operate for 200 h⁻¹. -1 Up to 1500h -1 Operating under GHSV, for example, 200h-1 Up to 1200h -1 400h -1 Up to 1200h -1 600 h -1 Up to 1000h -1 700 h -1 Up to 900h -1 Approximately 800 hours -1 Or any subset thereof, under GHSV.

[0100] The second fixed-bed reactor 120 can produce a second reactor effluent 130. The second reactor effluent 130 may contain aromatic compounds having six to eight carbon atoms. Aromatic compounds having six to eight carbon atoms may include benzene, toluene, ethylbenzene, xylene, or combinations thereof. The second reactor effluent 130 may also contain any unreacted component from the pyrolysis oil feed 102, intermediate stream 118, or both, such as unreacted heavy aromatic compounds. Based on the total weight of the second reactor effluent 130, the second reactor effluent 130 may include at least 50% by weight of liquid product at room temperature, for example, at least 60% by weight, at least 70% by weight, at least 73% by weight, 50% to 80% by weight, 60% to 80% by weight, and 70% to 80% by weight of liquid product. Based on the total weight of the second reactor effluent 130, at least 20% by weight, such as at least 30% by weight, at least 35% by weight, at least 40% by weight, at least 45% by weight, 20% to 60% by weight, 30% to 60% by weight, 40% to 60% by weight, and 45% to 60% by weight of aromatic compounds having 6 to 8 carbon atoms generated in the second fixed-bed reactor 120.

[0101] Compared to upgrading pyrolysis oil using conventional single-stage catalytic methods, upgrading pyrolysis oil feed 102 using the two-stage catalytic method of this disclosure can produce higher yields of benzene, toluene, ethylbenzene, xylene, or combinations thereof. In an embodiment, based on the total weight of the pyrolysis oil in the pyrolysis oil feed 102 incorporating the two-stage catalytic process of this disclosure, the system 100 of this disclosure can produce a combined yield of greater than or equal to 30% by weight, greater than or equal to 35% by weight, greater than or equal to 40% by weight, or even greater than or equal to 45% by weight of benzene, toluene, ethylbenzene, xylene, or combinations thereof.

[0102] Refer again Figure 1 A method for upgrading pyrolysis oil feed 102 may include separating the second reactor effluent 130 into at least a BTEX product stream 144 and a residual underflow 146 in a separation unit 140. In an embodiment, the method may further include separating a light gas stream 142 from the second reactor effluent 130.

[0103] The separation unit 140 can be any unit capable of separating the BTEX product stream 144 from the residual underflow 146. In an embodiment, the separation unit can be a separation unit capable of separating the light gas stream 142 from the second reactor effluent 130.

[0104] The light gas stream 142 may contain gases. In an embodiment, the light gas stream 142 may contain hydrogen and C1-C4 hydrocarbons, such as methane, ethane, propane, and butane. In an embodiment, the light gas stream 142 may contain at least 80% by weight of the combined weight of hydrogen and C1-C4 hydrocarbons, for example, at least 90% by weight, at least 95% by weight, or even at least 99% by weight of the combined weight of hydrogen and C1-C4 hydrocarbons.

[0105] BTEX product stream 144 may contain light aromatic compounds, such as benzene, toluene, ethylbenzene, and xylene. In an embodiment, BTEX product stream 144 may contain at least 80% by weight, such as at least 90% by weight, at least 95% by weight, or even at least 99% by weight, of light aromatic compounds.

[0106] The residual underflow 146 may contain polycyclic aromatic hydrocarbons, bicyclic aromatic hydrocarbons, and tricyclic aromatic hydrocarbons. In an embodiment, all or part of the residual underflow 146 may be returned to the first fixed-bed reactor 110 as bottom recirculation stream 150.

[0107] Still refer to Figure 1 A method for upgrading pyrolysis oil feed 102 may include contacting the pyrolysis oil feed 102 with hydrogen 116 under reaction conditions in the presence of a mixed metal oxide catalyst 112 to produce an intermediate stream 118 comprising bicyclic aromatic compounds and / or tricyclic aromatic compounds. As previously described in this disclosure, contacting the pyrolysis oil feed 102 with hydrogen 116 under reaction conditions in the presence of the mixed metal oxide catalyst 112 can convert at least a portion of the polycyclic aromatic compounds in the pyrolysis oil feed 102 into bicyclic aromatic compounds and / or tricyclic aromatic compounds. Reaction conditions may include a temperature of 300°C to 500°C, a pressure of 1 MPa (10 bar) to 20 MPa (200 bar), a volume ratio of the mixed metal oxide catalyst 112 to the pyrolysis oil feed 102 in the first fixed-bed reactor 110 ranging from 500 to 1500, or combinations of these reaction conditions.

[0108] The first fixed-bed reactor 110 may have any of the characteristics, catalysts, or operating conditions of the first fixed-bed reactor 110 previously discussed in this disclosure. The method may also include contacting the pyrolysis oil feed 102 and hydrogen 116 with the secondary catalyst 111 in the first fixed-bed reactor 110. The pyrolysis oil feed 102 may contact the secondary catalyst 111 under substantially the same conditions as the conditions under which the pyrolysis oil feed 102 is contacted with the mixed metal oxide catalyst 112.

[0109] The method may include passing an intermediate stream 118 comprising bicyclic aromatic compounds and / or tricyclic aromatic compounds to a second fixed-bed reactor 120 downstream of a first fixed-bed reactor 110. The method may include contacting the intermediate stream 118 with hydrogen gas 124 under reaction conditions in the presence of a mesoporous supported metal catalyst 122 to produce a second reactor effluent 130 comprising an aromatic compound having six to eight carbon atoms. As previously described in this disclosure, contacting the intermediate stream 118 with hydrogen gas 124 under reaction conditions in the presence of the mesoporous supported metal catalyst 122 can cause at least a portion of the bicyclic aromatic compounds and / or tricyclic aromatic compounds in the intermediate stream 118 to react to form an aromatic compound having six to eight carbon atoms. Reaction conditions may include a temperature of 300°C to 500°C, a pressure of 1 MPa (10 bar) to 20 MPa (200 bar), or a combination of these reaction conditions. The second fixed-bed reactor 120 may have any of the characteristics, catalysts, or operating conditions of the second fixed-bed reactor 120 previously discussed in this disclosure.

[0110] According to a first aspect, a method for upgrading pyrolysis oil may include contacting a pyrolysis oil feed with hydrogen in a first fixed-bed reactor in the presence of a mixed metal oxide catalyst, wherein: the pyrolysis oil feed comprises a polycyclic aromatic hydrocarbon (PAH) compound having sixteen or more carbon atoms; the mixed metal oxide catalyst comprises a plurality of MMO particles, and each of the plurality of MMO particles comprises Fe₂O₃, ZrO₂, CeO₂, and Al₂O₃; and in the first fixed-bed reactor, contacting the pyrolysis oil feed with hydrogen in the presence of the mixed metal oxide catalyst results in at least a portion of the PAH compound in the pyrolysis oil feed being contacted with hydrogen. A reaction occurs to produce an intermediate stream comprising bicyclic aromatic compounds, tricyclic aromatic compounds, or combinations thereof; in a second fixed-bed reactor, the intermediate stream is contacted with hydrogen in the presence of a mesoporous supported metal catalyst, wherein: the mesoporous supported metal catalyst comprises nickel and tungsten impregnated on a mesoporous support, said mesoporous support comprising macroporous alumina, a binder, and at least one zeolite; contacting the intermediate stream with hydrogen in the presence of the mesoporous supported metal catalyst causes at least a portion of the bicyclic aromatic compounds and / or tricyclic aromatic compounds in the intermediate stream to react to produce a second reactor effluent comprising an aromatic compound having 6 to 8 carbon atoms.

[0111] According to the second aspect, in conjunction with the first aspect, the method may further include mixing heavy pyrolysis oil from a naphtha steam cracker with a light aromatic stream upstream of a first fixed-bed reactor to generate a pyrolysis oil feed, and transferring the pyrolysis oil feed to the first fixed-bed reactor.

[0112] According to the third aspect, combined with the second aspect, the light aromatic stream can be light pyrolysis oil from a gas steam cracker. According to the fourth aspect, in conjunction with any one of the second to third aspects, the light aromatic hydrocarbon stream can be essentially composed of aromatic hydrocarbons having 6 to 8 carbon atoms.

[0113] According to the fifth aspect, in conjunction with any one of the second to fourth aspects, the light aromatic stream may contain benzene, toluene, ethylbenzene, xylene, or combinations thereof.

[0114] According to the sixth aspect, in conjunction with any one of the second to fifth aspects, the pyrolysis oil feed may comprise 75% to 85% by weight of heavy pyrolysis oil and 15% to 25% by weight of light aromatic stream.

[0115] According to the seventh aspect, in conjunction with any one of the first to sixth aspects, an aromatic compound having six to eight carbon atoms may include benzene, toluene, ethylbenzene, xylene, or combinations thereof.

[0116] According to the eighth aspect, in conjunction with any one of the first to seventh aspects, the first fixed-bed reactor may include a first catalyst bed and a second catalyst bed located downstream of the first catalyst bed; the first catalyst bed may include a mixed metal oxide catalyst; the second catalyst bed may include a secondary catalyst; and the method may include contacting the pyrolysis oil feed and hydrogen with the mixed metal oxide catalyst in the first catalyst bed, and then with the secondary catalyst located downstream of the mixed metal oxide catalyst in the second catalyst bed in the first fixed-bed reactor.

[0117] According to aspect nine, in conjunction with aspect eight, the secondary catalyst may comprise nickel oxide, tungsten oxide, and zirconium oxide supported on a carrier material.

[0118] According to the tenth aspect, in conjunction with any one of the eighth to ninth aspects, based on the weight of the total metal oxides of the secondary catalyst, the secondary catalyst may comprise: 18.5 wt% to 21.5 wt% of Al2O3, 36.5 wt% to 39.5 wt% of SiO2, 9.2 wt% to 10.2 wt% of ZrO2, 10.5 wt% to 11.5 wt% of NiO, and 18.5 wt% to 21.5 wt% of WO3.

[0119] According to the eleventh aspect, in conjunction with any one of the first to tenth aspects, each MMO particle may comprise: 60% to 95% by weight of iron oxide; 1% to 20% by weight of zirconium oxide; 0.1% to 10% by weight of cerium oxide; and 1% to 20% by weight of aluminum oxide, wherein the weight percentages are based on the total weight of the MMO particles in the mixed metal oxide catalyst.

[0120] According to the twelfth aspect, in conjunction with any one of the first to eleventh aspects, each MMO particle may comprise: about 83% by weight of iron oxide; about 7.5% by weight of zirconium oxide; about 2.5% by weight of cerium oxide; and about 7.0% by weight of aluminum oxide, wherein the weight percentages are based on the total weight of the MMO particles in the mixed metal oxide catalyst.

[0121] According to aspect thirteen, in conjunction with any one of aspects one through twelfth, the mixed metal oxide catalyst may also include a binder material.

[0122] According to aspect fourteen, in conjunction with aspect thirteen, the binder material may include bentonite, silica, or both.

[0123] According to aspect fifteen, in conjunction with any one of aspects thirteen to fourteen, based on the total weight of the mixed metal oxide catalyst, the mixed metal oxide catalyst may contain 65% to 85% by weight of MMO particles.

[0124] According to aspect sixteen, in conjunction with any one of aspects one through fifteen, the mixed metal oxide catalyst may be in the form of granules.

[0125] According to aspect seventeen, in conjunction with aspect sixteen, the agglomerates of the mixed metal oxide catalyst may have a diameter of 1 mm to 3 mm.

[0126] According to aspect eighteen, in conjunction with any one of aspects sixteen to seventeen, the agglomerates of the mixed metal oxide catalyst can be cylindrical with a diameter of 1 mm to 3 mm and a length of 2 mm to 4 mm.

[0127] According to the nineteenth aspect, in conjunction with any one of the first to eighteenth aspects, the alumina of the mesoporous supported metal catalyst may comprise macroporous alumina with an average pore size of at least 5 nm.

[0128] According to aspect 20, in conjunction with any one of aspects 1 through 19, the zeolite of the mesoporous supported metal catalyst may comprise nano-β zeolite and USY zeolite.

[0129] According to aspect 21, in conjunction with any one of aspects 1 to 20, based on the total weight of the mesoporous supported metal catalyst, the mesoporous supported metal catalyst may comprise 2% to 10% macroporous alumina, 10% to 20% binder material, 40% to 60% zeolite, 4% to 8% nickel oxide, and 20% to 30% tungsten oxide; the zeolite may comprise USY zeolite and nano-sized β-zeolite; the weight ratio of USY zeolite to nano-sized β-zeolite may be 1.25 to 1.75.

[0130] According to aspect 22, in conjunction with any one of aspects 1 to 21, the mesoporous supported metal catalyst may comprise USY zeolite and nano-sized β zeolite, and the weight ratio of USY zeolite to nano-sized β zeolite may be 1.25 to 1.75. According to aspect 23, in conjunction with any one of aspects 1 to 22, based on the total weight of the mesoporous supported metal catalyst, the mesoporous supported metal catalyst may comprise about 7.5 wt% macroporous alumina, about 17.5 wt% β-zeolite, about 30 wt% USY zeolite, about 6 wt% nickel oxide, about 24 wt% tungsten oxide, and about 18 wt% binder. According to aspect 24, in conjunction with any one of aspects 1 to 23, based on the total weight of pyrolysis oil in the pyrolysis oil feed, the pyrolysis oil feed may contain greater than or equal to 30% by weight (wt.%) of polycyclic aromatic hydrocarbons having greater than or equal to 16 carbon atoms.

[0131] According to aspect twenty-five, in conjunction with any one of aspects one through twenty-four, the method may comprise contacting the pyrolysis oil feed with hydrogen in the presence of a mixed metal oxide catalyst in a first fixed-bed reactor under one or more of the following reaction conditions: (a) a temperature of 300°C to 500°C; (b) a pressure of 1 MPa (10 bar) to 20 MPa (200 bar); (c) a hydrogen to pyrolysis oil feed volume ratio of 500 to 1500, or a combination of these reaction conditions; and contacting the intermediate stream with hydrogen in the presence of a mesoporous supported metal catalyst in the presence of one or more of the following reaction conditions: (a) a temperature of 300°C to 500°C; (b) a pressure of 1 MPa (10 bar) to 20 MPa (200 bar), or a combination of these reaction conditions.

[0132] According to the twenty-sixth aspect, in conjunction with any one of the first to twenty-fifth aspects, in a first fixed-bed reactor, in the presence of a mixed metal oxide catalyst, the pyrolysis oil feed is contacted with hydrogen to convert a portion of the polycyclic aromatic hydrocarbons in the pyrolysis oil feed into an intermediate stream in a single step without subsequent chemical reaction steps.

[0133] According to aspect 27, in conjunction with any one of aspects 1 to 26, the method may include, in a second fixed-bed reactor, contacting the intermediate stream with hydrogen in the presence of a mesoporous supported metal catalyst under one or more of the following reaction conditions: (a) a temperature of 300°C to 500°C, (b) a pressure of 1 MPa (10 bar) to 20 MPa (200 bar), or a combination of these reaction conditions.

[0134] According to aspect 28, in conjunction with any one of aspects 1 to 27, in a second fixed-bed reactor, in the presence of a mesoporous supported metal catalyst, contacting the intermediate stream with hydrogen allows a portion of the intermediate stream to be converted into an aromatic compound having 6 to 8 carbon atoms in a single step without the need for subsequent chemical reaction steps.

[0135] According to aspect 29, in conjunction with any one of aspects 1 to 28, contacting the pyrolysis oil feed with hydrogen in the presence of a mixed metal oxide catalyst and contacting the intermediate stream with hydrogen in the presence of a mesoporous supported metal catalyst can result in a yield of aromatic compounds having 6 to 8 carbons greater than or equal to 45% by weight based on the total weight of the pyrolysis oil in the pyrolysis oil feed.

[0136] According to the thirtieth aspect, in conjunction with any one of the first to twenty-ninth aspects, the method may further include: steam cracking the naphtha stream to produce one or more product streams and heavy pyrolysis oil; and transferring the heavy pyrolysis oil as at least a portion of the pyrolysis oil feed to a first fixed-bed reactor.

[0137] According to aspect thirty-one, in conjunction with aspect thirty, the method may further include: steam cracking hydrocarbon gas to produce at least one light olefin stream and light pyrolysis oil; and transferring the light pyrolysis oil as at least a portion of the pyrolysis oil feed to a first fixed-bed reactor.

[0138] According to the thirty-second aspect, a system for upgrading pyrolysis oil may include a first fixed-bed reactor comprising a mixed metal oxide catalyst, wherein: the first fixed-bed reactor is operable to contact the pyrolysis oil feed with hydrogen in the presence of the mixed metal oxide catalyst to produce an intermediate stream comprising a bicyclic aromatic compound, a tricyclic aromatic compound, or both; the mixed metal oxide catalyst comprises a plurality of catalyst particles, each of which may comprise Fe2O3, ZrO2, CeO2, and Al2O3; a second fixed-bed reactor, which may be located downstream of the first fixed-bed reactor, and may comprise a mesoporous supported metal catalyst, wherein: the second fixed-bed reactor is operable to contact the intermediate stream with hydrogen in the presence of the mesoporous supported metal catalyst to produce a second reactor effluent comprising an aromatic compound having six to eight carbon atoms; and the mesoporous supported metal catalyst may comprise nickel and tungsten impregnated on a mesoporous support comprising alumina and at least one zeolite.

[0139] According to aspect 33, in conjunction with aspect 32, the catalyst particles of the mixed metal oxide catalyst may each comprise: 60% to 95% by weight of iron oxide; 1% to 20% by weight of zirconium oxide; 0.1% to 10% by weight of cerium oxide; and 1% to 20% by weight of aluminum oxide, wherein the weight percentages are based on the total weight of metal oxides in the catalyst particles of the mixed metal oxide catalyst.

[0140] According to aspect 34, in conjunction with any one of aspects 32 to 33, the mixed metal oxide catalyst may also include a binder material and a matrix material.

[0141] According to aspect 35, in conjunction with any one of aspects 32 to 34, the first fixed-bed reactor may include a first catalyst bed and a second catalyst bed located downstream of the first catalyst bed; the first catalyst bed may include a mixed metal oxide catalyst; and the second catalyst bed may include a secondary catalyst.

[0142] According to aspect thirty-six, in conjunction with any one of aspects thirty-two to thirty-five, based on the total weight of the oxide and the secondary catalyst, the secondary catalyst may comprise 18.5 wt% to 21.5 wt% of Al2O3, 36.5 wt% to 39.5 wt% of SiO2, 9.2 wt% to 10.2 wt% of ZrO2, 10.5 wt% to 11.5 wt% of NiO and 18.5 wt% to 21.5 wt% of WO3.

[0143] According to aspect 37, in conjunction with any one of aspects 32 to 36, the second fixed-bed reactor can be directly fluidly connected to the first fixed-bed reactor, such that the intermediate flow is directly transferred from the first fixed-bed reactor to the second fixed-bed reactor without passing through any intervening reactor or separation unit.

[0144] Example Various embodiments of the methods and systems for processing heavy oil will be further illustrated by the following examples. These examples are illustrative in nature and should not be construed as limiting the subject matter of this disclosure.

[0145] Example 1: Preparation of mixed metal oxide catalysts To prepare a mixed metal oxide catalyst comprising iron oxide, zirconium oxide, cerium oxide, and aluminum oxide, 40 g of ferric nitrate (III) nonahydrate (Fe(NO3)3·9H2O) was dissolved in 800 mL of distilled water to obtain solution A. Subsequently, other metal oxide precursors were added to solution A. Specifically, 4.906 g of aluminum nitrate (Al(NO3)3·9H2O) nonahydrate, 1.549 g of zirconium oxynitrate (IV) hydrate (ZrO(NO3)2:3H2O), and 0.601 g of cerium nitrate (III) hexahydrate (Ce(NO3)3·6H2O) were added to solution A to form solution B. Solution B was then stirred for 30 minutes.

[0146] An ammonia solution, solution C, is prepared by adding 40 mL of ammonium hydroxide (NH4OH) (containing 28-30% NH3) to 60 mL of distilled water. Solution C is then slowly added to solution B to prepare solution D. Solution C is continuously added until the pH of solution D reaches approximately 7. Solution D is then stirred for another hour.

[0147] After preparing solution D and stirring for one hour, the precipitate was separated from solution D and dried in an oven overnight (approximately 12 hours). The dried precipitate was then calcined in air at 500°C for two hours. After calcination, the dried and calcined precipitate was pulverized to obtain fine MMO particles. The MMO particles were nanoparticles with a particle size ranging from 20 nm to 200 nm.

[0148] The powdered MMO particles were then mixed with bentonite and methylcellulose in the following proportions: 75 wt% powdered MMO catalyst, 24.9 wt% bentonite, and 0.1 wt% methylcellulose. The weights of the MMO particles and bentonite were based on the weights of these components after calcination, determined using loss on ignition (LOI). The LOI of each component was determined by accurately weighing 3 grams of each component into a crucible and recording the added mass of each component. The crucible was placed in a furnace, and the components were heated to 650°C at a heating rate of 2°C / min and held at 650°C for 2 hours to calcine each component. After calcination, the crucible was removed from the furnace and placed in a desiccator to cool, preventing reabsorption of atmospheric moisture or other components. The calcined components were then reweighed and their masses recorded. The LOI of each component was calculated based on the recorded masses after calcination and the recorded masses before calcination.

[0149] The dried components are mixed thoroughly. Then, approximately 1.5 mL of water and 1 g of catalyst are mixed to form an extrudable paste. The extrudable paste is injected into the syringe of the injection pump and extruded at a rate of 3 mL / min into cylinders with a diameter of 2.1 mm.

[0150] The extruded samples were dried in an oven at 60°C for 24 hours. The dried samples were then calcined in air at a heating rate of 2°C / min to 650°C for 2 hours. The calcined samples were then cooled to room temperature and broken into agglomerates. The agglomerates were subsequently sieved to obtain a subset of mixed metal oxide catalyst agglomerates with a maximum overall size of 1 mm to 2 mm. The characteristics of the mixed metal oxide catalyst agglomerates are shown in Table 2.

[0151] Table 2

[0152] Example 2: Preparation of mesoporous supported metal catalysts In Example 2, a mesoporous supported metal catalyst was prepared by first preparing a binder composition. 29.25 g of alumina binder (CATAPAL B, purchased from Sasol Germany GmbH) was combined with 63.3 g of water and 3.45 mL of 67% to 69% HNO3 to form a homogeneous binder paste.

[0153] Then, a zeolite paste was prepared. 7.4 g of macroporous alumina (with a porosity of 150 μm) was added. 2Brunauer-Emmett-Teller (BET) surface area ( / g), pore volume (0.8 mL / g to 1.1 mL / g), and pore radius (11 nm); CATAPAL B (purchased from Sasol Inc.), 49.2 g of USY zeolite (CBV-720 purchased from Zeolyst International), and 28.6 g of nano-β zeolite were combined to prepare a zeolite mixture. Detailed information on the nano-β zeolite is shown in Table 3. The zeolite mixture was then mixed with a homogeneous binder paste to form a carrier paste.

[0154] Table 3

[0155] The carrier paste was injected into the syringe of the injection pump and extruded into cylinders with a diameter of 2.1 mm at a rate of 3 mL / min. The extruded sample was dried overnight in an oven at 110 °C. The dried sample was then heated to 550 °C and calcined in air for 4 hours at a heating rate of 2 °C / min. The cooled sample was then broken into particles with a length of approximately 2 mm to approximately 4 mm.

[0156] The pellets were then impregnated with metallic nickel (Ni) and tungsten (W). This was achieved through merging (NH4). 10 (H2W 12 O 42 A Ni / W metal solution was prepared using ammonium metatungstate (Ammonium metatungstate), Ni(NO3)2·6H2O (Ni nitrate hexahydrate), and water. The agglomerates were mixed with the Ni / W metal solution at room temperature for 3 hours. The impregnated sample was dried overnight in an oven at 110°C. The dried sample was then calcined in air at a heating rate of 2°C / min to 500°C for 4 hours.

[0157] Example 3: Upgrading of pyrolysis oil via two-stage hydrocracking In Example 3, the performance of a method for upgrading pyrolysis oil, comprising the mixed metal oxide catalyst of Example 1 and the mesoporous supported metal catalyst of Example 2, was evaluated. For Example 3, 80 wt% of heavy pyrolysis oil from a flow cracker was mixed with 20 wt% of light pyrolysis oil from a gas steam cracker to prepare the pyrolysis oil feed. Simulated distillation of the pyrolysis oil feed is shown in Table 4. The proportions of naphtha, diesel, and C16+ fractions in the pyrolysis oil feed are shown in Table 4. Table 5 provides the percentage of each different class of aromatic compounds in the pyrolysis oil feed based on the total weight of the pyrolysis oil feed.

[0158] The pyrolysis oil feed and hydrogen are introduced together into the first fixed-bed reactor. The pyrolysis oil feed is preheated to the reactor operating temperature before introduction. The first reactor comprises a first bed and a second bed downstream of the first bed. The first bed comprises 2.3 g of the mixed metal oxide (MMO) catalyst prepared according to Example 1. Downstream of the MMO catalyst bed, but still within the first reactor, the second catalyst bed comprises 1.8 g of a secondary catalyst comprising 18 wt% to 21.5 wt% alumina, 36.5 wt% to 39.5 wt% silica, 9.2 wt% to 10.2 wt% zirconium oxide, 10.5 wt% to 11.5 wt% nickel oxide, and 18.5 wt% to 21.5 wt% tungsten oxide.

[0159] The pyrolysis oil feed was introduced into the first fixed-bed reactor at a liquid hourly space velocity (LHSV) of 0.3 h⁻¹. -1 The atmospheric space velocity (GHSV) is 800 h. -1 The pressure was 150 bar and the reactor temperature was 390°C.

[0160] Subsequently, the intermediate product generated in the first reactor was introduced into a second fixed-bed reactor. The second fixed-bed reactor comprised the mesoporous supported metal catalyst bed prepared in Example 2. The second fixed-bed reactor was incubated for 1.2 h. -1 LHSV, 800 h -1 The reactor was operated at GHSV, a pressure of 150 bar, and a reactor temperature of 380°C. Analysis was performed on the outlet of the second fixed-bed reactor, including simulated distillation, gaseous product analysis, and liquid product analysis. The results of the simulated distillation are shown in Table 4, and the aromatics analysis results are shown in Table 5.

[0161] Gas product analysis: The content of gaseous products was analyzed by online gas chromatography equipped with FID and TCD detectors.

[0162] Liquid product analysis: API gravity was measured using an Anton Paar DMA 4100M densitometer, according to ASTM D4052 and D5002 standards.

[0163] Sulfur and nitrogen content were analyzed using Mitsubishi, Antek, and Analytick Jena analyzers according to ASTM D4629. Gaseous hydrocarbons were defined as C1 to C4 hydrocarbons. Naphtha was defined as C5 hydrocarbons up to hydrocarbons boiling at 173°C. Diesel fuel was defined as hydrocarbons boiling at 173°C to 404°C. 16+ Hydrocarbons are defined as hydrocarbons that boil at temperatures above 404°C.

[0164] Simulated distillation was performed on an Agilent 7890 gas chromatograph according to CSN EN 15199-2 standard. Viscosity was analyzed according to ASTM D7042 standard.

[0165] Table 4

[0166] Table 5

[0167] As shown in Table 5, this process converts a large number of bicyclic and tricyclic aromatic hydrocarbons into monocyclic aromatic hydrocarbons, thereby facilitating the production of useful chemicals.

[0168] Comparative Example A (CE-A): Upgrading of pyrolysis oil via two-stage hydrocracking In Comparative Example A, the performance of the same feed used in Example 3 was evaluated using a single reactor and a single catalyst system. In Comparative Example A, 80% by weight of heavy pyrolysis oil from a flow cracker and 20% by weight of light pyrolysis oil from a gas steam cracker were mixed to prepare the pyrolysis oil feed. The proportions of naphtha, diesel, and C16+ fractions in the pyrolysis oil feed are shown in Table 4.

[0169] The pyrolysis oil feed and hydrogen are introduced together into the first fixed-bed reactor. Prior to introduction, the pyrolysis oil feed is preheated to the reactor operating temperature. The first reactor contains only a secondary catalyst (3.6 g total). The secondary catalyst comprises 18 wt% to 21.5 wt% alumina, 36.5 wt% to 39.5 wt% silica, 9.2 wt% to 10.2 wt% zirconium oxide, 10.5 wt% to 11.5 wt% nickel oxide, and 18.5 wt% to 21.5 wt% tungsten oxide.

[0170] The pyrolysis oil feed was introduced into the first fixed-bed reactor at a liquid hourly space velocity (LHSV) of 0.3 h⁻¹. -1 The atmospheric space velocity (GHSV) is 800 h. -1 The pressure was 150 bar and the reactor temperature was 390°C.

[0171] The outlet of the first fixed-bed reactor was analyzed in the same manner as the product stream in Example 3. The results of this analysis are shown in Table 6.

[0172] Table 6

[0173] It should be noted that any two quantitative values ​​assigned to a certain attribute can constitute a range of that attribute, and this disclosure considers all range combinations formed by all the stated quantitative values ​​of a given attribute.

[0174] It should be noted that the term "where" is used as a transitional phrase in one or more of the following claims. In defining this technology, it should be noted that this term is introduced in the claims as an open-ended transitional phrase to introduce a series of features of the structure, and should be interpreted in a similar manner to the more commonly used open-ended leading term "comprising."

[0175] Having described the subject matter of this disclosure in detail and referenced specific aspects, it should be noted that the various details of these aspects should not be construed as implying that such details are essential components of these aspects. Rather, the appended claims should be considered the sole expression of the breadth of this disclosure and the corresponding scope of the various aspects described herein. Furthermore, modifications and variations may obviously be made without departing from the scope of the appended claims.

Claims

1. A method for upgrading pyrolysis oil, the method comprising: In the first fixed-bed reactor, the pyrolysis oil feed is contacted with hydrogen in the presence of a mixed metal oxide catalyst, wherein: The pyrolysis oil feed contains polycyclic aromatic hydrocarbon compounds having sixteen or more carbon atoms. The mixed metal oxide catalyst comprises a plurality of MMO particles, and each of the plurality of MMO particles comprises Fe2O3, ZrO2, CeO2, and Al2O3; and In the first fixed-bed reactor, in the presence of the mixed metal oxide catalyst, the pyrolysis oil feed is contacted with hydrogen, causing at least a portion of the polycyclic aromatic hydrocarbons in the pyrolysis oil feed to react and produce an intermediate stream comprising bicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons, or combinations thereof. In the second fixed-bed reactor, the intermediate stream is contacted with hydrogen in the presence of a mesoporous supported metal catalyst, wherein: The mesoporous supported metal catalyst comprises nickel and tungsten impregnated on a mesoporous support, wherein the mesoporous support comprises macroporous alumina, a binder and at least one zeolite; In the presence of the mesoporous supported metal catalyst, contacting the intermediate stream with hydrogen causes at least a portion of the bicyclic aromatic compounds and / or tricyclic aromatic compounds in the intermediate stream to react, producing a second reactor effluent containing aromatic compounds having 6 to 8 carbon atoms.

2. The method according to claim 1, further comprising mixing heavy pyrolysis oil from a naphtha steam cracker with a light aromatics stream upstream of the first fixed-bed reactor to generate the pyrolysis oil feed, and transferring the pyrolysis oil feed to the first fixed-bed reactor, wherein, The pyrolysis oil feed comprises 75% to 85% by weight of the heavy pyrolysis oil and 15% to 25% by weight of the light aromatic stream.

3. The method according to claim 1 or 2, wherein: The first fixed-bed reactor includes a first catalyst bed and a second catalyst bed located downstream of the first catalyst bed; The first catalyst bed comprises the mixed metal oxide catalyst; The second catalyst bed contains a secondary catalyst; as well as The method includes contacting the pyrolysis oil feed and hydrogen with the mixed metal oxide catalyst in the first catalyst bed, and then contacting it with the secondary catalyst downstream of the mixed metal oxide catalyst in the second catalyst bed in the first fixed-bed reactor.

4. The method according to claim 3, wherein, Based on the total weight of the metal oxides in the secondary catalyst, the secondary catalyst comprises: 18.5 wt% to 21.5 wt% Al2O3, 36.5% to 39.5% by weight of SiO2, 9.2 wt% to 10.2 wt% ZrO2, 10.5 wt% to 11.5 wt% NiO, and WO3, ranging from 18.5% to 21.5% by weight.

5. The method according to any one of claims 1 to 4, wherein each of the MMO particles comprises: 60% to 95% by weight of iron oxide; Zirconia from 1% to 20% by weight; 0.1% to 10% by weight of cerium oxide; and 1% to 20% by weight of alumina, The weight percentage is based on the total weight of the MMO particles in the mixed metal oxide catalyst.

6. The method according to any one of claims 1 to 5, wherein the mixed metal oxide catalyst further comprises a binder material.

7. The method according to any one of claims 1 to 6, wherein the mixed metal oxide catalyst is in the form of granules.

8. The method according to any one of claims 1 to 7, wherein the alumina of the mesoporous supported metal catalyst comprises macroporous alumina with an average pore size of at least 5 nm.

9. The method according to any one of claims 1 to 8, wherein the zeolite of the mesoporous supported metal catalyst comprises nano-β zeolite and USY zeolite.

10. The method according to any one of claims 1 to 9, wherein: Based on the total weight of the mesoporous supported metal catalyst, the mesoporous supported metal catalyst comprises 2 wt% to 10 wt% of the macroporous alumina, 10 wt% to 20 wt% of the binder material, 40 wt% to 60 wt% of the zeolite, 4 wt% to 8 wt% of the nickel oxide, and 20 wt% to 30 wt% of the tungsten oxide. The zeolite comprises USY zeolite and nano-sized β-zeolite; and The weight ratio of USY zeolite to nano-sized β-zeolite is 1.25 to 1.

75.

11. The method according to any one of claims 1 to 10, wherein: Based on the total weight of the pyrolysis oil in the pyrolysis oil feed, the pyrolysis oil feed contains greater than or equal to 30% by weight (wt.%) of polycyclic aromatic hydrocarbons having greater than or equal to 16 carbon atoms; and Contacting the pyrolysis oil feed with hydrogen in the presence of the mixed metal oxide catalyst, and contacting the intermediate stream with hydrogen in the presence of the mesoporous zeolite supported metal catalyst, results in a yield of the aromatic compound having 6 to 8 carbons greater than or equal to 45% by weight based on the total weight of the pyrolysis oil in the pyrolysis oil feed.

12. The method according to any one of claims 1 to 11, comprising: In the first fixed-bed reactor, in the presence of the mixed metal oxide catalyst, the pyrolysis oil feed is contacted with hydrogen under one or more of the following reaction conditions: (a) a temperature of 300°C to 500°C; (b) a pressure of 1 MPa (10 bar) to 20 MPa (200 bar); (c) a hydrogen-to-pyrolysis oil feed volume ratio of 500 to 1500, or a combination of these reaction conditions; and In the second fixed-bed reactor, in the presence of the mesoporous supported metal catalyst, the intermediate stream is contacted with hydrogen under one or more of the following reaction conditions: (a) a temperature of 300°C to 500°C, (b) a pressure of 1 MPa (10 bar) to 20 MPa (200 bar), or a combination of these reaction conditions.

13. The method according to any one of claims 1 to 12, further comprising: Steam cracking of naphtha streams to produce one or more product streams and heavy pyrolysis oil; and The heavy pyrolysis oil is fed into the first fixed-bed reactor as at least a portion of the pyrolysis oil feed.

14. The method of claim 13, further comprising: Steam cracking of hydrocarbon gases to produce at least one light olefin stream and light pyrolysis oil; The light pyrolysis oil is fed into the first fixed-bed reactor as at least a portion of the pyrolysis oil feed.

15. A system for upgrading pyrolysis oil, the system comprising: The first fixed-bed reactor contains a mixed metal oxide catalyst, wherein: The first fixed-bed reactor is operable to contact the pyrolysis oil feed with hydrogen in the presence of the mixed metal oxide catalyst to produce an intermediate stream containing light aromatic compounds, including monocyclic aromatic compounds, bicyclic aromatic compounds, tricyclic aromatic compounds, or both. The mixed metal oxide catalyst comprises a plurality of catalyst particles, each of which contains Fe2O3, ZrO2, CeO2, and Al2O3. A second fixed-bed reactor, located downstream of the first fixed-bed reactor, comprises a mesoporous supported metal catalyst, wherein: The second fixed-bed reactor is operable to contact the intermediate stream with hydrogen in the presence of the mesoporous supported metal catalyst to produce a second reactor effluent containing an aromatic compound having 6 to 8 carbon atoms; and The mesoporous supported metal catalyst comprises nickel and tungsten impregnated on a mesoporous support, wherein the mesoporous support comprises alumina and at least one zeolite.

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