WO2020003100A1 - Process and system for producing para-xylene - Google Patents

Process and system for producing para-xylene Download PDF

Info

Publication number
WO2020003100A1
WO2020003100A1 PCT/IB2019/055311 IB2019055311W WO2020003100A1 WO 2020003100 A1 WO2020003100 A1 WO 2020003100A1 IB 2019055311 W IB2019055311 W IB 2019055311W WO 2020003100 A1 WO2020003100 A1 WO 2020003100A1
Authority
WO
WIPO (PCT)
Prior art keywords
stream
hydrocracking
xylene
toluene
product
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/IB2019/055311
Other languages
French (fr)
Inventor
Thomas Hubertus Maria HOUSMANS
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SABIC Global Technologies BV
Original Assignee
SABIC Global Technologies BV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SABIC Global Technologies BV filed Critical SABIC Global Technologies BV
Priority to CN201980042977.0A priority Critical patent/CN112313193B/en
Priority to US17/254,351 priority patent/US11192834B2/en
Priority to KR1020207034538A priority patent/KR102783306B1/en
Publication of WO2020003100A1 publication Critical patent/WO2020003100A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2/00Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms
    • C07C2/86Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation between a hydrocarbon and a non-hydrocarbon
    • C07C2/862Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation between a hydrocarbon and a non-hydrocarbon the non-hydrocarbon contains only oxygen as hetero-atoms
    • C07C2/864Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation between a hydrocarbon and a non-hydrocarbon the non-hydrocarbon contains only oxygen as hetero-atoms the non-hydrocarbon is an alcohol
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2/00Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms
    • C07C2/54Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by addition of unsaturated hydrocarbons to saturated hydrocarbons or to hydrocarbons containing a six-membered aromatic ring with no unsaturation outside the aromatic ring
    • C07C2/64Addition to a carbon atom of a six-membered aromatic ring
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C15/00Cyclic hydrocarbons containing only six-membered aromatic rings as cyclic parts
    • C07C15/02Monocyclic hydrocarbons
    • C07C15/067C8H10 hydrocarbons
    • C07C15/08Xylenes
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C4/00Preparation of hydrocarbons from hydrocarbons containing a larger number of carbon atoms
    • C07C4/02Preparation of hydrocarbons from hydrocarbons containing a larger number of carbon atoms by cracking a single hydrocarbon or a mixture of individually defined hydrocarbons or a normally gaseous hydrocarbon fraction
    • C07C4/06Catalytic processes
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00Purification; Separation; Use of additives
    • C07C7/005Processes comprising at least two steps in series
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G47/00Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions

Definitions

  • hydrocracking can be used to convert highly complex hydrocarbon streams into less complex streams containing fewer components.
  • These less complex streams can include fuel gas (e.g., hydrogen, methane), liquefied petroleum gas (LPG) (e.g., ethane, propane, butane), benzene, toluene, and xylene.
  • fuel gas e.g., hydrogen, methane
  • LPG liquefied petroleum gas
  • benzene e.g., ethane, propane, butane
  • benzene e.g., benzene, toluene
  • xylene e.g., xylene
  • benzene and xylene products can be produced by hydrocracking hydrocarbon feeds and processing the hydrocracking product with extractive distillation, toluene disproportionation, and selective transalkylation.
  • benzene can be produced by hydrodealkylation of toluene.
  • benzene is separated from the hydrocracking product to ensure on- specification benzene levels in the production of gasoline.
  • the remaining toluene (which is produced in relatively significant amounts due to thermodynamics) and xylene can be used as a gasoline component due to its high octane value.
  • a process for producing a para-xylene product from a hydrocarbon feed comprises: hydrocracking the hydrocarbon feed in the presence of a catalyst to obtain a hydrocracking product; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9 + hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 70 weight ercent (wt%), preferably equal to or greater than 80 wt%, more preferably equal to or greater than 95 wt%, based on the total weight of the toluene stream; and reacting the toluene stream with methanol to obtain the para-xylene product.
  • wt% weight ercent
  • a process for producing a para-xylene product from a hydrocarbon feed comprises: hydrocracking the hydrocarbon feed in the presence of a catalyst to produce a hydrocracking product at a temperature of 300°C to 580°C, preferably 325°C to 575°C, more preferably 350°C to 550°C and a pressure of 0.3 MegaPascals (MPa) to 5.0 MPa, preferably 0.5 MPa to 4.0 MPa, more preferably 1 MPa to 3 MPa; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9 + hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 95 wt%, preferably equal to greater than 96 wt%, more preferably equal to
  • a system for producing a para-xylene product comprises: a hydrocracking unit for producing a hydrocracking product; a first separation unit for separating the hydrocracking product to obtain a gas stream and a liquid stream; a second separation unit for separating the liquid stream to obtain a toluene stream; and a methylation unit for reacting the toluene stream with methanol to obtain the para-xylene product.
  • the Figure is an illustration of an embodiment of a process for producing a para- xylene from a hydrocarbon feed.
  • the processes and systems can convert hydrocarbon feeds to the higher value para-xylene product with high selectivity.
  • By-products can be converted or recycled within the processes and systems so that, in addition to the para-xylene product, the product streams include xylene, benzene, and LPG products.
  • Previous processes and systems for producing para-xylene from hydrocarbon feeds e.g., hydrocracking and/or steam cracking
  • produced mixtures of aliphatic hydrocarbons and aromatic hydrocarbons that required separation of the aliphatic hydrocarbons from the aromatic components before further processing e.g., conversion of toluene to para-xylene).
  • Such separation processes which include extractive distillation, can be capital and energy intensive.
  • the present processes and systems avoid processes such as extractive distillation, as separation of aliphatic hydrocarbons from aromatic hydrocarbons before further processing of the aromatic hydrocarbons is not required.
  • the present processes and systems avoid processing of toluene via disproportionation or hydrodealkylation, as conversion of toluene to para-xylene is achieved via methylation.
  • toluene disproportionation production of more benzene from toluene through selective toluene disproportionation can be reduced or avoided and the selectivity for para-xylene is increased.
  • hydrodealkylation of toluene the significant amounts of fuel gas produced by such processes are avoided.
  • the present processes and systems for producing a para-xylene product have simplified logistics, less processing units, and a higher production ratio of para-xylenes to benzene as compared to previous processes for converting hydrocarbon feeds into a para-xylene product. For instance, in a situation where the unit is fed with a reformate stream with the following composition: paraffins 15 wt%; benzene 10 wt%; toluene 30 wt%; ethyl-benzene 5 wt%; xylenes 30 wt%;
  • the molar ratio of xylene produced to benzene produced can be equal to or greater than 4: 1, for example, 4.75:1 in case all toluene is successfully methylated to xylenes. It is to be noted, that the xylene/benzene ratio depends strongly upon the feedstock. The values listed above are a typical reformate stream as feedstock.
  • the equilibrium of ortho, meta, and para-xylene is typically 22:54:24%.
  • para-xylene product refers to a composition including para-xylene in an amount equal to or greater than 50 wt%, based on the total weight of the para- xylene product.
  • xylene refers to a mixture of ortho-xylene, meta-xylene, para-xylene, and ethylbenzene, wherein para-xylene is present in an amount less than 50 wt%, based on the total weight of the xylenes.
  • a process for producing a para-xylene product from a hydrocarbon feed can include hydrocracking the hydrocarbon feed in the presence of a catalyst to obtain a
  • hydrocracking product separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9 + hydrocarbon, or a
  • the toluene is present in the toluene stream in an amount equal to or greater than 70 wt%, for example, equal to or greater than 80 wt%, for example, equal to or greater than 95 wt%, based on the total weight of the toluene stream.
  • “C9 + hydrocarbon” refers to a hydrocarbon including nine or more carbon atoms.
  • Desirable hydrocarbon feeds include, but are not limited to, hydrogenated depentanized hydrotreated gasoline, naphtha (such as straight ran naphtha or light coker naphtha), pyrolysis gasoline (e.g., first stage hydro-treated pyrolysis gasoline), hydrocracked gasoline, coke oven light oil, fluid catalytic cracking (FCC) gasoline, reformate, kerosene,
  • pyrolysis gasoline e.g., first stage hydro-treated pyrolysis gasoline
  • hydrocracked gasoline e.g., coke oven light oil, fluid catalytic cracking (FCC) gasoline, reformate, kerosene
  • the hydrocarbon feed can include naphtha.
  • a majority of the hydrocarbon feed comprises C 6 -Cs hydrocarbons.
  • hydrocracking refers to a catalytic cracking process in the presence of hydrogen.
  • hydrocracking unit refers to a reactor unit capable of performing a hydrocracking process.
  • a majority of the effluent produced by hydrocracking can be LPG, which includes alkanes that can be converted to olefins.
  • the hydrocracking can keep intact one aromatic ring of the aromatics in the hydrocarbon feed, but remove most of the side-chains from the aromatic ring.
  • the hydrocracking can be achieved by adjusting the hydrogenation activity of the catalyst, process temperature, or space velocity of the hydrocarbon feed.
  • the processes and systems operate one or more hydrocracking units at moderate temperatures and pressures.
  • the process conditions used for hydrocracking can include a temperature of 300°C to 580°C, for example, 325°C to 575°C, for example, 350°C to 550°C and a pressure of 0.3 MPa to 20.0 MPa, for example, 0.5 MPa to 4.0 MPa, for example, 1 MPa to 3 MPa.
  • a first hydrocracking unit can be operated at a temperature of 300°C to 500°C, for example, 400°C to 500°C and at a pressure of 0.5 MPa to 3.0 MPa, for example, 1.0 MPa to 2.5 MPa.
  • a second hydrocracking unit can be operated at a temperature of 400°C to 600°C, for example, 450°C to 550°C and at a pressure of 0.5 MPa to 3.0 MPa, for example, 1.0 MPa to 2.5 MPa.
  • catalysts used for the hydrocracking process include various transition metals, or metal sulfides with a solid support such as alumina, silica, alumina- silica, magnesia, zeolites, or a combination comprising at least one of the foregoing.
  • the catalyst can include 0.01 wt to 1 wt% hydrogenation metal in relation to the total catalyst weight and a zeolite having a pore size of 5 to 8 Angstroms (A) and a silica (SiCk) to alumina (AI2O3) molar ratio of 5: 1 to 200: 1.
  • the hydrocracking can be in the presence of one catalyst. In another embodiment, the hydrocracking can be in the presence of two catalysts.
  • the step of hydrocracking the hydrocarbon feed to produce a hydrocracking product can be in one or more stages.
  • a first stage can include hydrocracking the hydrocarbon feed to obtain a first hydrocracking product and then separating the first hydrocracking product to obtain a light stream, which can be gaseous, and a heavy stream, which can be a liquid.
  • a single hydrocracking step can be performed in multiple reactors. When greater than one reactor is used, tailoring of the C 1-C4 stream can be allowed. For example, by first mild hydrocracking and then more severe hydrocracking, the ethane/propane/(benzene, toluene, xylene) ratio can be tuned. However, a single step can be possible as well.
  • the light stream separated from the first hydrocracking product can include hydrogen and C1-C4 hydrocarbons.
  • the heavy stream separated from the first hydrocracking product can include C5+ hydrocarbons.
  • “C 1 -4 hydrocarbons” refers to hydrocarbons including 1 to 4 carbon atoms.
  • Hydrogen can be present in the first hydrocracking product in an amount equal to or greater than 1 wt%, for example, 2 wt% to 10 wt%, for example, 2 wt% to 8 wt%, based on the total weight of the first hydrocracking product.
  • the C1-C4 hydrocarbons e.g., LPG
  • LPG LPG
  • the heavy stream can include C5 + hydrocarbons and aromatic hydrocarbons.
  • the heavy stream can include C5 + hydrocarbons in an amount equal to or greater than 1 wt%, for example, 2 wt% to 20 wt%, for example, 5 wt% to 10 wt%, based on the total weight of the heavy stream.
  • the heavy stream can include aromatic hydrocarbons in an amount equal to or greater than 1 wt%, for example, 5 wt% to 25 wt%, for example, 10 wt% to 20 wt %, based on the total weight of the heavy stream.
  • a second stage can include hydrocracking the heavy stream to obtain a second hydrocracking product.
  • the second hydrocracking product obtained from hydrocracking the heavy stream can include hydrogen, methane, ethane, propane, butane, benzene, toluene, xylene, C 9+ hydrocarbon, or a combination comprising at least one of the foregoing.
  • the second hydrocracking product can be separated to obtain the gas stream and the liquid stream including benzene, toluene, xylene, C 9+ hydrocarbon, or a combination comprising at least one of the foregoing.
  • the gas stream can include hydrogen, methane, ethane, propane, butane, or a combination comprising at least one of the foregoing.
  • the hydrocracking product (e.g., the first hydrocracking product or the second hydrocracking product) can include benzene, toluene, and xylene in an amount of 20 wt% to over 90 wt% (and even 100 wt%, in some cases, can be possible provided that the feedstock fed to the hydrocrackers is easily crackable), for example, 30 wt% to 70 wt%, for example, 40 wt% to 60 wt , based on the total weight of the hydrocracking product.
  • Toluene can be present in the hydrocracking product in an amount of 10 wt% to 70 wt%, for example, 20 wt% to 60 wt%, for example, 30 wt% to 50 wt%, based on the total weight of the hydrocracking product.
  • the hydrocracking product e.g., the liquid stream
  • the hydrocracking product e.g., the liquid stream
  • the hydrocracking product can be substantially devoid of C 5 -C 7 aliphatic hydrocarbons (i.e., aliphatic hydrocarbons with 5 to 7 carbon atoms).
  • Separating the hydrocracking product can include distilling the hydrocracking product to obtain the liquid stream.
  • the separating of the liquid stream can include distilling the liquid stream.
  • the process for producing a para-xylene product can further include, before or during the step of separating the liquid stream to obtain the toluene stream, separating a xylene stream from the liquid stream and transalkylating the xylene stream to obtain para-xylene.
  • the process for producing a para-xylene product can further include, before or during the step of separating the liquid stream to obtain the toluene stream, separating a C 9+ hydrocarbon stream from the liquid stream.
  • the process for producing a para-xylene product can further include recycling the C9 + hydrocarbon stream to the step of hydrocracking (e.g., the first stage, the second stage, or subsequent stages of the step of hydrocracking).
  • the reacting of the toluene with methanol to obtain para-x ylene can be in the presence of a catalyst.
  • a catalyst for toluene methylation include, but are not limited to, an acidic catalyst, preferably a zeolite catalyst.
  • zeolite catalyst for example, ZSM-5-type zeolite, zeolite Beta and silicaaluminophosphate (SAPO) catalysts have been used for toluene methylation.
  • SAPO silicaaluminophosphate
  • the para-xylene can be present in the para-xylene product an amount equal to or greater than 95 wt%, for example, equal to greater than 96 wt%, for example, equal to or greater than 97 wt%, based on the total weight of the para-xylene product.
  • disproportionation, hydrodealkylation, extractive distillation, or a combination of at least one of the foregoing, are not present in the process for producing a para- xylene product.
  • a process for producing a para-xylene product from a hydrocarbon feed can include: (i) hydrocracking the hydrocarbon feed in the presence of a catalyst to produce a hydrocracking product at a temperature of 300°C to 580°C, for example, 325°C to 575°C, for example, 350°C to 550°C and a pressure of 0.3 MPa to 5.0 MPa, for example, 0.5 MPa to 4.0 MPa, for example, 1 MPa to 3 MPa, (ii) separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9 + hydrocarbon, or a combination comprising at least one of the foregoing, (iii) separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 95 wt%, for example, equal to greater than 96 w
  • a para-xylene product can be produced by the above-described processes.
  • a system for producing a para-xylene product can include a hydrocracking unit for producing a hydrocracking product, a first separation unit for separating the hydrocracking product to obtain a gas stream and a liquid stream, a second separation unit for separating the liquid stream to obtain a toluene stream, and a methylation unit for reacting the toluene stream with methanol to obtain the para-xylene product.
  • a hydrocarbon feed 2 can be hydrocracked over a catalyst in a first hydrocracking unit 10 to produce a first hydrocracking product 12.
  • the hydrocarbon feed 2 can be mixed with hydrogen 4 and heated.
  • the first hydrocracking product 12 can comprise hydrogen, Ci-C 4 hydrocarbons (such as liquefied petroleum gas), and Cs + hydrocarbons (i.e., those comprising five or more carbon atoms), including aromatic hydrocarbons such as benzene, toluene, and xylene (BTX).
  • the first hydrocracking product 12 enters a first separation unit 20.
  • the first separation unit 20 separates hydrogen and Ci-C 4 hydrocarbons from C5 + hydrocarbons to obtain a light stream 24 and a heavy stream 22, respectively.
  • the heavy stream 22 is hydrocracked in a second hydrocracking unit 30 to convert at least a portion of the C 5+ hydrocarbons into C 1 -C 4 hydrocarbons and aromatic hydrocarbons.
  • conversion of at least a portion of the C 5+ hydrocarbons into C 1 -C 4 hydrocarbons and aromatic hydrocarbons can be achieved in the second
  • hydrocracking unit 30 without the use of paraffinic and naphthenic co-boilers, which can affect the purity of the aromatic products.
  • the heavy stream 22 and hydrogen 4 react over a catalyst to produce a second hydrocracking product 32.
  • first hydrocracking unit 10 and the second hydrocracking unit 30 are each shown as one single unit, it is to be understood that in alternate embodiments the hydrocracking units comprise multiple reactors.
  • a hydrocracking unit can comprise one, two, three, four, or more fixed-bed reactors or one, two, three, four, or more fluidized bed reactors in series, each comprising a catalyst.
  • intermediate coolers can be located among the reactors to remove the heat of the reaction by, for instance, producing high pressure steam.
  • a second separation unit 40 removes hydrogen and light hydrocarbons (e.g., C5- hydrocarbons) in the second hydrocracking product 32 from aromatic hydrocarbons. Hydrogen and light hydrocarbons in a gas stream 49 are directed to the first separation unit 20, while aromatic hydrocarbons enter a distillation train where sequential separation of benzene 42, Cs hydrocarbons 44, toluene 46, and C9 + hydrocarbons 48 occurs.
  • hydrogen and light hydrocarbons e.g., C5- hydrocarbons
  • second separation unit 40 is shown as one single unit, it is to be understood that in alternate embodiment’ s second separation comprise multiple distillation columns making up the distillation train.
  • a hydrocracking unit can comprise one, two, three, four, or more simple distillation columns in series.
  • the toluene 46 is fed to a reactor 50 and reacted with methanol to obtain a para-xylene product 52.
  • the Cg + hydrocarbons 48 can be recycled to the hydrocracking unit 30.
  • a process for producing para-xylene from a hydrocarbon feed was performed with hydrogenated depentanized hydrotreated gasoline using the process illustrated in the Figure.
  • Table 1 shows the C 7 fraction from a run using the hydrogenated depentanized hydrotreated gasoline (HPHG) with mild hydrocracking (MHC).
  • Operating conditions for the mild hydrocracking were a temperature of 425 to 475°C and a pressure of 13 to 15 barg (13.1 MPa to 15.1 MPa).
  • the benzene purity was 99.88 wt%, based on the total weight of the benzene stream, while the toluene purity was 99.5 wt%, based on the total weight of the toluene stream.
  • the toluene conversion was 41.7%
  • the toluene selectivity to the para-xylene product was 93.1%
  • para-xylene was present in the para-xylene product in an amount of 83.3 weight%, based on the total weight of the para-xylene product.
  • Methanol and toluene can be recycled to maximize conversion. Heavies (e.g., greater than C9 + ) can be recycled in the hydrocracking unit or can be sold.
  • the processes and systems of the present disclosure achieved higher yields of para-xylene from a hydrocarbon feedstock, such as naphtha, while reducing the capital and energy expenditure.
  • conventional processes use greater capital and energy expenditure because they use extractive distillation to separate aliphatic hydrocarbons from aromatic hydrocarbons before further processing of aromatic hydrocarbons.
  • Conventional processes require the combined use of hydrogenation, distillation, and extractive distillation to produce the desired product, while the use of hydrocracking in the present process generally removes all aliphatic components from aromatics by conversion to gas which is easily separated. The remaining aromatics have few to no co-boilers and can be further separated with simple distillation.
  • the processes and systems of the present disclosure produce a higher molar ratio of para-xylene to benzene.
  • a process for producing a para-xylene product from a hydrocarbon feed comprising: hydrocracking the hydrocarbon feed in the presence of a catalyst to obtain a hydrocracking product; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9 + hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 70 wt%, preferably equal to or greater than 80 wt%, more preferably equal to or greater than 95 wt%, based on the total weight of the toluene stream; and reacting the toluene stream with methanol to obtain the para-xylene product.
  • Aspect 2 The process of Aspect 1, wherein the hydrocarbon feed comprises hydrogenated depentanized hydrotreated gasoline, naphtha, pyrolysis gasoline, hydrocracked gasoline, coke oven light oil, fluid catalytic cracking gasoline, reformate, kerosene, C5-C12 hydrocarbons, or a combination comprising at least one of the foregoing.
  • Aspect 3 The process of any one or more of the preceding aspects, wherein the hydrocracking is in the presence of one catalyst.
  • Aspect 4 The process of any one or more of the preceding aspects, wherein the hydrocracking product is substantially devoid of aliphatic hydrocarbons.
  • Aspect 5 The process of any one or more of the preceding aspects, wherein separating the hydrocracking product comprises distilling the hydrocracking product to obtain the liquid stream.
  • Aspect 6 The process of any one or more of the preceding aspects, wherein the gas stream comprises hydrogen, methane, ethane, propane, butane, or a combination comprising at least one of the foregoing.
  • Aspect 7 The process of any one or more of the preceding aspects, wherein separating the liquid stream comprises distilling the liquid stream.
  • Aspect 8 The process of any one or more of the preceding aspects, further comprising, before or during the step of separating the liquid stream to obtain the toluene stream, separating a xylene stream from the liquid stream and transalkylating the xylene stream to obtain para-x ylene.
  • Aspect 9 The process of any one or more of the preceding aspects, further comprising, before or during the step of separating the liquid stream to obtain the toluene stream, separating a C9 + hydrocarbon stream from the liquid stream.
  • Aspect 10 The process of Aspect 8, further comprising recycling the C9 + hydrocarbon stream to the step of hydrocracking.
  • Aspect 11 The process of any one or more of the preceding aspects, wherein the para-x ylene is present in the para-x ylene product an amount equal to or greater than 95 wt%, preferably equal to greater than 96 wt%, more preferably equal to or greater than 97 wt%, based on the total weight of the para-x ylene product.
  • Aspect 12 The process of any one or more of the preceding aspects, wherein disproportionation, hydrodealkylation, extractive distillation, or a combination of at least one of the foregoing, are not present in the process.
  • Aspect 13 The process of any one or more of the preceding aspects, wherein the liquid stream comprises less than 1 wt% of C5-C7 aliphatic hydrocarbons.
  • Aspect 14 The process of any one or more of the preceding aspects, wherein the liquid stream comprises less than 1 wt% aliphatic hydrocarbon, based on the total weight of the liquid stream.
  • Aspect 15 The process of any one or more of the preceding aspects, without processing of the toluene via disproportionation or hydrodealkylation.
  • Aspect 16 The process of any one or more of the preceding aspects, wherein the hydrocracking was at a temperature of 300°C to 580°C, preferably 325°C to 575°C, more preferably 350°C to 550°C and a pressure of 0.3 MPa to 5.0 MPa, preferably 0.5 MPa to 4.0 MPa, more preferably 1 MPa to 3 MPa;
  • a process for producing a para-xylene product from a hydrocarbon feed comprising: hydrocracking the hydrocarbon feed in the presence of a catalyst to produce a hydrocracking product at a temperature of 300°C to 580°C, preferably 325°C to 575°C, more preferably 350°C to 550°C and a pressure of 0.3 MPa to 5.0 MPa, preferably 0.5 MPa to 4.0 MPa, more preferably 1 MPa to 3 MPa; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9 + hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 95 wt%, preferably equal to greater than 96 wt%, more preferably equal to or greater
  • Aspect 18 A para-xylene product produced by the process of any one or more of the preceding aspects.
  • a system for producing a para-xylene product comprising: a hydrocracking unit for producing a hydrocracking product; a first separation unit for separating the hydrocracking product to obtain a gas stream and a liquid stream; a second separation unit for separating the liquid stream to obtain a toluene stream; and a methylation unit for reacting the toluene stream with methanol to obtain the para-xylene product.
  • Aspect 20 The system of Claim 19, wherein no disproportionation unit or hydrodealkylation unit is present between the hydrocracking unit and the methylation unit.
  • the invention may alternately comprise, consist of, or consist essentially of, any appropriate components herein disclosed.
  • the invention may additionally, or alternatively, be formulated so as to be devoid, or substantially free, of any components, materials, ingredients, adjuvants or species used in the prior art compositions or that are otherwise not necessary to the achievement of the function and/or objectives of the present invention.
  • the endpoints of all ranges directed to the same component or property are inclusive and independently combinable (e.g., ranges of“less than or equal to 25 wt%, or 5 wt% to 20 wt%,” is inclusive of the endpoints and all intermediate values of the ranges of“5 wt% to 25 wt%,” etc.).

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

A process for producing a para-xylene product from a hydrocarbon feed includes: hydrocracking the hydrocarbon feed in the presence of a catalyst to obtain a hydrocracking product; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9+ hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 70 wt%, preferably equal to or greater than 80 wt%, more preferably equal to or greater than 95 wt%, based on the total weight of the toluene stream; and reacting the toluene stream with methanol to obtain the para-xylene product.

Description

PROCESS AND SYSTEM FOR PRODUCING PARA -XYLENE
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is an international application claiming priority to US
Application No. 62/689,401, filed lune 25, 2018, which is incorporated herein by reference in its entirety.
BACKGROUND
[0001] In the petrochemical industry, hydrocracking can be used to convert highly complex hydrocarbon streams into less complex streams containing fewer components. These less complex streams can include fuel gas (e.g., hydrogen, methane), liquefied petroleum gas (LPG) (e.g., ethane, propane, butane), benzene, toluene, and xylene.
[0002] For instance, benzene and xylene products can be produced by hydrocracking hydrocarbon feeds and processing the hydrocracking product with extractive distillation, toluene disproportionation, and selective transalkylation. Alternatively, benzene can be produced by hydrodealkylation of toluene.
[0003] Often, benzene is separated from the hydrocracking product to ensure on- specification benzene levels in the production of gasoline. The remaining toluene (which is produced in relatively significant amounts due to thermodynamics) and xylene can be used as a gasoline component due to its high octane value.
SUMMARY
[0004] Disclosed, in various embodiments, are processes and systems for producing para-xylene.
[0005] A process for producing a para-xylene product from a hydrocarbon feed, comprises: hydrocracking the hydrocarbon feed in the presence of a catalyst to obtain a hydrocracking product; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9+ hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 70 weight ercent (wt%), preferably equal to or greater than 80 wt%, more preferably equal to or greater than 95 wt%, based on the total weight of the toluene stream; and reacting the toluene stream with methanol to obtain the para-xylene product.
[0006] A process for producing a para-xylene product from a hydrocarbon feed, comprises: hydrocracking the hydrocarbon feed in the presence of a catalyst to produce a hydrocracking product at a temperature of 300°C to 580°C, preferably 325°C to 575°C, more preferably 350°C to 550°C and a pressure of 0.3 MegaPascals (MPa) to 5.0 MPa, preferably 0.5 MPa to 4.0 MPa, more preferably 1 MPa to 3 MPa; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9+ hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 95 wt%, preferably equal to greater than 96 wt%, more preferably equal to or greater than 97 wt%, based on the total weight of the toluene stream; and reacting the toluene stream with methanol to obtain the para-xylene product.
[0007] A system for producing a para-xylene product, comprises: a hydrocracking unit for producing a hydrocracking product; a first separation unit for separating the hydrocracking product to obtain a gas stream and a liquid stream; a second separation unit for separating the liquid stream to obtain a toluene stream; and a methylation unit for reacting the toluene stream with methanol to obtain the para-xylene product.
[0008] These and other features and characteristics are more particularly described below.
BRIEF DESCRIPTION OF THE DRAWING
[0009] The following figure is an exemplary embodiment which is presented for the purposes of illustrating an exemplary embodiment disclosed herein and not for the purposes of limiting the same.
[0010] The Figure is an illustration of an embodiment of a process for producing a para- xylene from a hydrocarbon feed.
[0011] The above described and other features are exemplified by the following detailed description, examples, and claims.
DETAILED DESCRIPTION
[0012] Described herein are processes and systems for producing a para-xylene product from a hydrocarbon feed. In particular, the processes and systems can convert hydrocarbon feeds to the higher value para-xylene product with high selectivity. By-products can be converted or recycled within the processes and systems so that, in addition to the para-xylene product, the product streams include xylene, benzene, and LPG products. Previous processes and systems for producing para-xylene from hydrocarbon feeds (e.g., hydrocracking and/or steam cracking) produced mixtures of aliphatic hydrocarbons and aromatic hydrocarbons that required separation of the aliphatic hydrocarbons from the aromatic components before further processing (e.g., conversion of toluene to para-xylene). Such separation processes, which include extractive distillation, can be capital and energy intensive. Desirably, in some embodiments, the present processes and systems avoid processes such as extractive distillation, as separation of aliphatic hydrocarbons from aromatic hydrocarbons before further processing of the aromatic hydrocarbons is not required.
[0013] Moreover, in some embodiments, the present processes and systems avoid processing of toluene via disproportionation or hydrodealkylation, as conversion of toluene to para-xylene is achieved via methylation. By avoiding toluene disproportionation, production of more benzene from toluene through selective toluene disproportionation can be reduced or avoided and the selectivity for para-xylene is increased. By avoiding hydrodealkylation of toluene, the significant amounts of fuel gas produced by such processes are avoided. Thus, the present processes and systems for producing a para-xylene product have simplified logistics, less processing units, and a higher production ratio of para-xylenes to benzene as compared to previous processes for converting hydrocarbon feeds into a para-xylene product. For instance, in a situation where the unit is fed with a reformate stream with the following composition: paraffins 15 wt%; benzene 10 wt%; toluene 30 wt%; ethyl-benzene 5 wt%; xylenes 30 wt%;
C9+ aromatics 10 wt%, the molar ratio of xylene produced to benzene produced can be equal to or greater than 4: 1, for example, 4.75:1 in case all toluene is successfully methylated to xylenes. It is to be noted, that the xylene/benzene ratio depends strongly upon the feedstock. The values listed above are a typical reformate stream as feedstock.
[0014] Additionally, the equilibrium of ortho, meta, and para-xylene is typically 22:54:24%. This means that the ratio of para-xylene/benzene depends on whether or not an isomerization unit is used. Assuming this is the case, nearly all mixed xylenes would be converted to para-xylene and thus the ratio would be approximately the same. Further, it is interesting to note that the selectivity of toluene methylation to para-xylene is nearly 100%. Thus, the present process not only eliminates the need of benzene and toluene extraction through extractive distillation, it reduces the size of the required isomerization unit. In contrast, previous processes using toluene disproportionation had a molar ratio of xylene produced to benzene produced about 1.5:1, while other processes using hydrodealkylation of toluene had a molar ratio of xylene produced to benzene produced of about 0.6: 1. When full conversion of mixed-xylenes is achieved through an isomerization unit, these ratios can be considered close to the ratio between para-xylene and benzene.
[0015] As used herein“para-xylene product” refers to a composition including para-xylene in an amount equal to or greater than 50 wt%, based on the total weight of the para- xylene product. As used herein,“xylene” refers to a mixture of ortho-xylene, meta-xylene, para-xylene, and ethylbenzene, wherein para-xylene is present in an amount less than 50 wt%, based on the total weight of the xylenes.
[0016] A process for producing a para-xylene product from a hydrocarbon feed can include hydrocracking the hydrocarbon feed in the presence of a catalyst to obtain a
hydrocracking product, separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9+ hydrocarbon, or a
combination comprising at least one of the foregoing, separating the liquid stream to obtain a toluene stream, and reacting the toluene stream with methanol to obtain the para-xylene product. The toluene is present in the toluene stream in an amount equal to or greater than 70 wt%, for example, equal to or greater than 80 wt%, for example, equal to or greater than 95 wt%, based on the total weight of the toluene stream. As referred to herein,“C9+ hydrocarbon” refers to a hydrocarbon including nine or more carbon atoms.
[0017] Desirable hydrocarbon feeds include, but are not limited to, hydrogenated depentanized hydrotreated gasoline, naphtha (such as straight ran naphtha or light coker naphtha), pyrolysis gasoline (e.g., first stage hydro-treated pyrolysis gasoline), hydrocracked gasoline, coke oven light oil, fluid catalytic cracking (FCC) gasoline, reformate, kerosene,
C5-C12 hydrocarbons, or a combination comprising at least one of the foregoing. Desirably, the hydrocarbon feed can include naphtha. In an embodiment, a majority of the hydrocarbon feed comprises C6-Cs hydrocarbons.
[0018] As used herein,“hydrocracking” refers to a catalytic cracking process in the presence of hydrogen. As used herein,“hydrocracking unit” refers to a reactor unit capable of performing a hydrocracking process. A majority of the effluent produced by hydrocracking can be LPG, which includes alkanes that can be converted to olefins. The hydrocracking can keep intact one aromatic ring of the aromatics in the hydrocarbon feed, but remove most of the side-chains from the aromatic ring. The hydrocracking can be achieved by adjusting the hydrogenation activity of the catalyst, process temperature, or space velocity of the hydrocarbon feed.
[0019] Desirably, the processes and systems operate one or more hydrocracking units at moderate temperatures and pressures. The process conditions used for hydrocracking can include a temperature of 300°C to 580°C, for example, 325°C to 575°C, for example, 350°C to 550°C and a pressure of 0.3 MPa to 20.0 MPa, for example, 0.5 MPa to 4.0 MPa, for example, 1 MPa to 3 MPa. A first hydrocracking unit can be operated at a temperature of 300°C to 500°C, for example, 400°C to 500°C and at a pressure of 0.5 MPa to 3.0 MPa, for example, 1.0 MPa to 2.5 MPa. A second hydrocracking unit can be operated at a temperature of 400°C to 600°C, for example, 450°C to 550°C and at a pressure of 0.5 MPa to 3.0 MPa, for example, 1.0 MPa to 2.5 MPa.
[0020] Many catalysts used for the hydrocracking process include various transition metals, or metal sulfides with a solid support such as alumina, silica, alumina- silica, magnesia, zeolites, or a combination comprising at least one of the foregoing. In an embodiment, the catalyst can include 0.01 wt to 1 wt% hydrogenation metal in relation to the total catalyst weight and a zeolite having a pore size of 5 to 8 Angstroms (A) and a silica (SiCk) to alumina (AI2O3) molar ratio of 5: 1 to 200: 1.
[0021] In an embodiment, the hydrocracking can be in the presence of one catalyst. In another embodiment, the hydrocracking can be in the presence of two catalysts.
[0022] Desirably, the step of hydrocracking the hydrocarbon feed to produce a hydrocracking product can be in one or more stages. For instance, a first stage can include hydrocracking the hydrocarbon feed to obtain a first hydrocracking product and then separating the first hydrocracking product to obtain a light stream, which can be gaseous, and a heavy stream, which can be a liquid. In an embodiment, a single hydrocracking step can be performed in multiple reactors. When greater than one reactor is used, tailoring of the C 1-C4 stream can be allowed. For example, by first mild hydrocracking and then more severe hydrocracking, the ethane/propane/(benzene, toluene, xylene) ratio can be tuned. However, a single step can be possible as well.
[0023] The light stream separated from the first hydrocracking product can include hydrogen and C1-C4 hydrocarbons. The heavy stream separated from the first hydrocracking product can include C5+ hydrocarbons. As refer to herein,“C 1 -4 hydrocarbons” refers to hydrocarbons including 1 to 4 carbon atoms.
[0024] Hydrogen can be present in the first hydrocracking product in an amount equal to or greater than 1 wt%, for example, 2 wt% to 10 wt%, for example, 2 wt% to 8 wt%, based on the total weight of the first hydrocracking product. The C1-C4 hydrocarbons (e.g., LPG) can be present in an amount equal to or greater than 30 wt%, for example, equal to or greater than 40 wt%, for example, equal to or greater 50 wt%, based on the total weight of the first
hydrocracking product.
[0025] The heavy stream can include C5+ hydrocarbons and aromatic hydrocarbons. For instance, the heavy stream can include C5+ hydrocarbons in an amount equal to or greater than 1 wt%, for example, 2 wt% to 20 wt%, for example, 5 wt% to 10 wt%, based on the total weight of the heavy stream. In certain embodiments, the heavy stream can include aromatic hydrocarbons in an amount equal to or greater than 1 wt%, for example, 5 wt% to 25 wt%, for example, 10 wt% to 20 wt %, based on the total weight of the heavy stream.
[0026] A second stage can include hydrocracking the heavy stream to obtain a second hydrocracking product. The second hydrocracking product obtained from hydrocracking the heavy stream can include hydrogen, methane, ethane, propane, butane, benzene, toluene, xylene, C9+ hydrocarbon, or a combination comprising at least one of the foregoing.
[0027] The second hydrocracking product can be separated to obtain the gas stream and the liquid stream including benzene, toluene, xylene, C9+ hydrocarbon, or a combination comprising at least one of the foregoing. The gas stream can include hydrogen, methane, ethane, propane, butane, or a combination comprising at least one of the foregoing.
[0028] The hydrocracking product (e.g., the first hydrocracking product or the second hydrocracking product) can include benzene, toluene, and xylene in an amount of 20 wt% to over 90 wt% (and even 100 wt%, in some cases, can be possible provided that the feedstock fed to the hydrocrackers is easily crackable), for example, 30 wt% to 70 wt%, for example, 40 wt% to 60 wt , based on the total weight of the hydrocracking product. Toluene can be present in the hydrocracking product in an amount of 10 wt% to 70 wt%, for example, 20 wt% to 60 wt%, for example, 30 wt% to 50 wt%, based on the total weight of the hydrocracking product.
[0029] The hydrocracking product (e.g., the liquid stream) can be substantially devoid of aliphatic hydrocarbon (i.e., include less than 1 wt%, based on the total weight of the
hydrocracking product). For example, the hydrocracking product (e.g., the liquid stream) can be substantially devoid of C5-C7 aliphatic hydrocarbons (i.e., aliphatic hydrocarbons with 5 to 7 carbon atoms).
[0030] Separating the hydrocracking product can include distilling the hydrocracking product to obtain the liquid stream.
[0031] Desirably, in the process for producing a para-xylene product, the separating of the liquid stream can include distilling the liquid stream.
[0032] In addition to using methylation to produce para-xylene product, the process for producing a para-xylene product can further include, before or during the step of separating the liquid stream to obtain the toluene stream, separating a xylene stream from the liquid stream and transalkylating the xylene stream to obtain para-xylene.
[0033] The process for producing a para-xylene product can further include, before or during the step of separating the liquid stream to obtain the toluene stream, separating a C9+ hydrocarbon stream from the liquid stream. The process for producing a para-xylene product can further include recycling the C9+ hydrocarbon stream to the step of hydrocracking (e.g., the first stage, the second stage, or subsequent stages of the step of hydrocracking).
[0034] The reacting of the toluene with methanol to obtain para-x ylene can be in the presence of a catalyst. Desirable catalysts for toluene methylation include, but are not limited to, an acidic catalyst, preferably a zeolite catalyst. For example, ZSM-5-type zeolite, zeolite Beta and silicaaluminophosphate (SAPO) catalysts have been used for toluene methylation.
[0035] The para-xylene can be present in the para-xylene product an amount equal to or greater than 95 wt%, for example, equal to greater than 96 wt%, for example, equal to or greater than 97 wt%, based on the total weight of the para-xylene product.
[0036] Desirably, disproportionation, hydrodealkylation, extractive distillation, or a combination of at least one of the foregoing, are not present in the process for producing a para- xylene product.
[0037] A process for producing a para-xylene product from a hydrocarbon feed can include: (i) hydrocracking the hydrocarbon feed in the presence of a catalyst to produce a hydrocracking product at a temperature of 300°C to 580°C, for example, 325°C to 575°C, for example, 350°C to 550°C and a pressure of 0.3 MPa to 5.0 MPa, for example, 0.5 MPa to 4.0 MPa, for example, 1 MPa to 3 MPa, (ii) separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9+ hydrocarbon, or a combination comprising at least one of the foregoing, (iii) separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 95 wt%, for example, equal to greater than 96 wt%, for example, equal to or greater than 97 wt% based on the total weight of the toluene stream; and (iv) reacting the toluene stream with methanol to obtain the para-xylene product.
[0038] A para-xylene product can be produced by the above-described processes.
[0039] A system for producing a para-xylene product can include a hydrocracking unit for producing a hydrocracking product, a first separation unit for separating the hydrocracking product to obtain a gas stream and a liquid stream, a second separation unit for separating the liquid stream to obtain a toluene stream, and a methylation unit for reacting the toluene stream with methanol to obtain the para-xylene product.
[0040] A more complete understanding of the components, processes, and apparatuses disclosed herein can be obtained by reference to the accompanying Figure. The Figure is merely a schematic representation based on convenience and the ease of demonstrating the present disclosure, and is, therefore, not intended to indicate relative size and dimensions of the devices or components thereof and/or to define or limit the scope of the exemplary embodiments. Although specific terms are used in the following description for the sake of clarity, these terms are intended to refer only to the particular structure of the embodiment selected for illustration in the drawing, and are not intended to define or limit the scope of the disclosure.
[0041] In an exemplary process illustrated in the Figure, a hydrocarbon feed 2 can be hydrocracked over a catalyst in a first hydrocracking unit 10 to produce a first hydrocracking product 12. In the first hydrocracking unit 10, the hydrocarbon feed 2 can be mixed with hydrogen 4 and heated. The first hydrocracking product 12 can comprise hydrogen, Ci-C4 hydrocarbons (such as liquefied petroleum gas), and Cs+ hydrocarbons (i.e., those comprising five or more carbon atoms), including aromatic hydrocarbons such as benzene, toluene, and xylene (BTX).
[0042] After partial cooling, the first hydrocracking product 12 enters a first separation unit 20. The first separation unit 20 separates hydrogen and Ci-C4 hydrocarbons from C5+ hydrocarbons to obtain a light stream 24 and a heavy stream 22, respectively.
[0043] The heavy stream 22 is hydrocracked in a second hydrocracking unit 30 to convert at least a portion of the C5+ hydrocarbons into C1-C4 hydrocarbons and aromatic hydrocarbons. In some embodiments, conversion of at least a portion of the C5+ hydrocarbons into C1-C4 hydrocarbons and aromatic hydrocarbons can be achieved in the second
hydrocracking unit 30 without the use of paraffinic and naphthenic co-boilers, which can affect the purity of the aromatic products. In the second hydrocracking unit 30, the heavy stream 22 and hydrogen 4 react over a catalyst to produce a second hydrocracking product 32.
[0044] Although the first hydrocracking unit 10 and the second hydrocracking unit 30 are each shown as one single unit, it is to be understood that in alternate embodiments the hydrocracking units comprise multiple reactors. For instance, a hydrocracking unit can comprise one, two, three, four, or more fixed-bed reactors or one, two, three, four, or more fluidized bed reactors in series, each comprising a catalyst. Optionally, intermediate coolers can be located among the reactors to remove the heat of the reaction by, for instance, producing high pressure steam.
[0045] A second separation unit 40 removes hydrogen and light hydrocarbons (e.g., C5- hydrocarbons) in the second hydrocracking product 32 from aromatic hydrocarbons. Hydrogen and light hydrocarbons in a gas stream 49 are directed to the first separation unit 20, while aromatic hydrocarbons enter a distillation train where sequential separation of benzene 42, Cs hydrocarbons 44, toluene 46, and C9+ hydrocarbons 48 occurs.
[0046] Although the second separation unit 40 is shown as one single unit, it is to be understood that in alternate embodiment’ s second separation comprise multiple distillation columns making up the distillation train. For instance, a hydrocracking unit can comprise one, two, three, four, or more simple distillation columns in series.
[0047] The toluene 46 is fed to a reactor 50 and reacted with methanol to obtain a para-xylene product 52.
[0048] The Cg+ hydrocarbons 48 can be recycled to the hydrocracking unit 30.
[0049] This disclosure is further illustrated by the following example, which is non limiting.
EXAMPLE
[0050] A process for producing para-xylene from a hydrocarbon feed was performed with hydrogenated depentanized hydrotreated gasoline using the process illustrated in the Figure. Table 1 shows the C7 fraction from a run using the hydrogenated depentanized hydrotreated gasoline (HPHG) with mild hydrocracking (MHC). Operating conditions for the mild hydrocracking were a temperature of 425 to 475°C and a pressure of 13 to 15 barg (13.1 MPa to 15.1 MPa).
Figure imgf000011_0001
[0051] After the mild hydrocracking, the benzene purity was 99.88 wt%, based on the total weight of the benzene stream, while the toluene purity was 99.5 wt%, based on the total weight of the toluene stream. In the step of reacting toluene with methanol, the toluene conversion was 41.7%, the toluene selectivity to the para-xylene product was 93.1%, and para-xylene was present in the para-xylene product in an amount of 83.3 weight%, based on the total weight of the para-xylene product. Methanol and toluene can be recycled to maximize conversion. Heavies (e.g., greater than C9+) can be recycled in the hydrocracking unit or can be sold.
[0052] Thus, in some embodiments, the processes and systems of the present disclosure achieved higher yields of para-xylene from a hydrocarbon feedstock, such as naphtha, while reducing the capital and energy expenditure. In contrast, conventional processes use greater capital and energy expenditure because they use extractive distillation to separate aliphatic hydrocarbons from aromatic hydrocarbons before further processing of aromatic hydrocarbons. Conventional processes require the combined use of hydrogenation, distillation, and extractive distillation to produce the desired product, while the use of hydrocracking in the present process generally removes all aliphatic components from aromatics by conversion to gas which is easily separated. The remaining aromatics have few to no co-boilers and can be further separated with simple distillation. In addition, in some embodiments, the processes and systems of the present disclosure produce a higher molar ratio of para-xylene to benzene.
[0053] The processes and system disclosed herein include(s) at least the following aspects:
[0054] Aspect 1: A process for producing a para-xylene product from a hydrocarbon feed, comprising: hydrocracking the hydrocarbon feed in the presence of a catalyst to obtain a hydrocracking product; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9+ hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 70 wt%, preferably equal to or greater than 80 wt%, more preferably equal to or greater than 95 wt%, based on the total weight of the toluene stream; and reacting the toluene stream with methanol to obtain the para-xylene product.
[0055] Aspect 2: The process of Aspect 1, wherein the hydrocarbon feed comprises hydrogenated depentanized hydrotreated gasoline, naphtha, pyrolysis gasoline, hydrocracked gasoline, coke oven light oil, fluid catalytic cracking gasoline, reformate, kerosene, C5-C12 hydrocarbons, or a combination comprising at least one of the foregoing.
[0056] Aspect 3: The process of any one or more of the preceding aspects, wherein the hydrocracking is in the presence of one catalyst.
[0057] Aspect 4: The process of any one or more of the preceding aspects, wherein the hydrocracking product is substantially devoid of aliphatic hydrocarbons.
[0058] Aspect 5: The process of any one or more of the preceding aspects, wherein separating the hydrocracking product comprises distilling the hydrocracking product to obtain the liquid stream.
[0059] Aspect 6: The process of any one or more of the preceding aspects, wherein the gas stream comprises hydrogen, methane, ethane, propane, butane, or a combination comprising at least one of the foregoing.
[0060] Aspect 7: The process of any one or more of the preceding aspects, wherein separating the liquid stream comprises distilling the liquid stream. [0061] Aspect 8: The process of any one or more of the preceding aspects, further comprising, before or during the step of separating the liquid stream to obtain the toluene stream, separating a xylene stream from the liquid stream and transalkylating the xylene stream to obtain para-x ylene.
[0062] Aspect 9: The process of any one or more of the preceding aspects, further comprising, before or during the step of separating the liquid stream to obtain the toluene stream, separating a C9+ hydrocarbon stream from the liquid stream.
[0063] Aspect 10: The process of Aspect 8, further comprising recycling the C9+ hydrocarbon stream to the step of hydrocracking.
[0064] Aspect 11: The process of any one or more of the preceding aspects, wherein the para-x ylene is present in the para-x ylene product an amount equal to or greater than 95 wt%, preferably equal to greater than 96 wt%, more preferably equal to or greater than 97 wt%, based on the total weight of the para-x ylene product.
[0065] Aspect 12: The process of any one or more of the preceding aspects, wherein disproportionation, hydrodealkylation, extractive distillation, or a combination of at least one of the foregoing, are not present in the process.
[0066] Aspect 13: The process of any one or more of the preceding aspects, wherein the liquid stream comprises less than 1 wt% of C5-C7 aliphatic hydrocarbons.
[0067] Aspect 14: The process of any one or more of the preceding aspects, wherein the liquid stream comprises less than 1 wt% aliphatic hydrocarbon, based on the total weight of the liquid stream.
[0068] Aspect 15: The process of any one or more of the preceding aspects, without processing of the toluene via disproportionation or hydrodealkylation.
[0069] Aspect 16: The process of any one or more of the preceding aspects, wherein the hydrocracking was at a temperature of 300°C to 580°C, preferably 325°C to 575°C, more preferably 350°C to 550°C and a pressure of 0.3 MPa to 5.0 MPa, preferably 0.5 MPa to 4.0 MPa, more preferably 1 MPa to 3 MPa;
[0070] Aspect 17: A process for producing a para-xylene product from a hydrocarbon feed, comprising: hydrocracking the hydrocarbon feed in the presence of a catalyst to produce a hydrocracking product at a temperature of 300°C to 580°C, preferably 325°C to 575°C, more preferably 350°C to 550°C and a pressure of 0.3 MPa to 5.0 MPa, preferably 0.5 MPa to 4.0 MPa, more preferably 1 MPa to 3 MPa; separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, C9+ hydrocarbon, or a combination comprising at least one of the foregoing; separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 95 wt%, preferably equal to greater than 96 wt%, more preferably equal to or greater than 97 wt% based on the total weight of the toluene stream; and reacting the toluene stream with methanol to obtain the para-xylene product.
[0071] Aspect 18: A para-xylene product produced by the process of any one or more of the preceding aspects.
[0072] Aspect 19: A system for producing a para-xylene product, comprising: a hydrocracking unit for producing a hydrocracking product; a first separation unit for separating the hydrocracking product to obtain a gas stream and a liquid stream; a second separation unit for separating the liquid stream to obtain a toluene stream; and a methylation unit for reacting the toluene stream with methanol to obtain the para-xylene product.
[0073] Aspect 20: The system of Claim 19, wherein no disproportionation unit or hydrodealkylation unit is present between the hydrocracking unit and the methylation unit.
[0074] In general, the invention may alternately comprise, consist of, or consist essentially of, any appropriate components herein disclosed. The invention may additionally, or alternatively, be formulated so as to be devoid, or substantially free, of any components, materials, ingredients, adjuvants or species used in the prior art compositions or that are otherwise not necessary to the achievement of the function and/or objectives of the present invention. The endpoints of all ranges directed to the same component or property are inclusive and independently combinable (e.g., ranges of“less than or equal to 25 wt%, or 5 wt% to 20 wt%,” is inclusive of the endpoints and all intermediate values of the ranges of“5 wt% to 25 wt%,” etc.). Disclosure of a narrower range or more specific group in addition to a broader range is not a disclaimer of the broader range or larger group. “Combination” is inclusive of blends, mixtures, alloys, reaction products, and the like. Furthermore, the terms“first,” “second,” and the like, herein do not denote any order, quantity, or importance, but rather are used to denote one element from another. The terms“a” and“an” and“the” herein do not denote a limitation of quantity, and are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. “Or” means“and/or.” The suffix“(s)” as used herein is intended to include both the singular and the plural of the term that it modifies, thereby including one or more of that term (e.g., the film(s) includes one or more films). Reference throughout the specification to“one embodiment”,“another embodiment”, “an embodiment”, and so forth, means that a particular element (e.g., feature, structure, and/or characteristic) described in connection with the embodiment is included in at least one embodiment described herein, and may or may not be present in other embodiments. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various embodiments.
[0075] The modifier“about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., includes the degree of error associated with measurement of the particular quantity). “Optional” or“optionally” means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where the event occurs and instances where it does not. Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this invention belongs.
[0076] All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if a term in the present application contradicts or conflicts with a term in the incorporated reference, the term from the present application takes precedence over the conflicting term from the incorporated reference.
[0077] While particular embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are or may be presently unforeseen may arise to applicants or others skilled in the art. Accordingly, the appended claims as filed and as they may be amended are intended to embrace all such alternatives, modifications variations, improvements, and substantial equivalents.

Claims

CLAIMS What is claimed is:
1. A process for producing a para-xylene product from a hydrocarbon feed, comprising:
hydrocracking the hydrocarbon feed in the presence of a catalyst to obtain a
hydrocracking product;
separating the hydrocracking product to obtain a gas stream and a liquid stream, the liquid stream comprising benzene, toluene, xylene, Cg+ hydrocarbon, or a combination comprising at least one of the foregoing;
separating the liquid stream to obtain a toluene stream, wherein toluene is present in the toluene stream in an amount equal to or greater than 70 wt%, preferably equal to or greater than 80 wt%, more preferably equal to or greater than 95 wt%, based on the total weight of the toluene stream; and
reacting the toluene stream with methanol to obtain the para-xylene product.
2. The process of Claim 1, wherein the hydrocarbon feed comprises hydrogenated depentanized hydrotreated gasoline, naphtha, pyrolysis gasoline, hydrocracked gasoline, coke oven light oil, fluid catalytic cracking gasoline, reformate, kerosene, C5-C12 hydrocarbons, or a combination comprising at least one of the foregoing.
3. The process of any one or more of the preceding claims, wherein the
hydrocracking is in the presence of one catalyst.
4. The process of any one or more of the preceding claims, wherein the
hydrocracking product is substantially devoid of aliphatic hydrocarbons.
5. The process of any one or more of the preceding claims, wherein separating the hydrocracking product comprises distilling the hydrocracking product to obtain the liquid stream.
6. The process of any one or more of the preceding claims, wherein the gas stream comprises hydrogen, methane, ethane, propane, butane, or a combination comprising at least one of the foregoing.
7. The process of any one or more of the preceding claims, wherein separating the liquid stream comprises distilling the liquid stream.
8. The process of any one or more of the preceding claims, further comprising, before or during the step of separating the liquid stream to obtain the toluene stream, separating a xylene stream from the liquid stream and transalkylating the xylene stream to obtain para-xylene.
9. The process of any one or more of the preceding claims, further comprising, before or during the step of separating the liquid stream to obtain the toluene stream, separating a C9+ hydrocarbon stream from the liquid stream.
10. The process of Claim 8, further comprising recycling the C9+ hydrocarbon stream to the step of hydrocracking.
11. The process of any one or more of the preceding claims, wherein the para-xylene is present in the para-xylene product an amount equal to or greater than 95 wt%, preferably equal to greater than 96 wt%, more preferably equal to or greater than 97 wt%, based on the total weight of the para-xylene product.
12. The process of any one or more of the preceding claims, wherein
disproportionation, hydrodealkylation, extractive distillation, or a combination of at least one of the foregoing, are not present in the process.
13. The process of any one or more of the preceding claims, wherein the liquid stream comprises less than 1 wt% of C5-C7 aliphatic hydrocarbons.
14. The process of any one or more of the preceding claims, wherein the liquid stream comprises less than 1 wt% aliphatic hydrocarbon, based on the total weight of the liquid stream.
15. The process of any one or more of the preceding claims, without processing of the toluene via disproportionation or hydrodealkylation.
16. The process of any one or more of the preceding claims, wherein the
hydrocracking was at a temperature of 300°C to 580°C, preferably 325°C to 575°C, more preferably 350°C to 550°C and a pressure of 0.3 MPa to 5.0 MPa, preferably 0.5 MPa to 4.0 MPa, more preferably 1 MPa to 3 MPa.
17. A para-xylene product produced by the process of any one or more of the preceding claims.
18. A system for producing a para-xylene product, comprising:
a hydrocracking unit for producing a hydrocracking product;
a first separation unit for separating the hydrocracking product to obtain a gas stream and a liquid stream;
a second separation unit for separating the liquid stream to obtain a toluene stream; and a methylation unit for reacting the toluene stream with methanol to obtain the para- xylene product.
19. The system of Claim 18, wherein no disproportionation unit or hydrodealkylation unit is present between the hydrocracking unit and the methylation unit.
PCT/IB2019/055311 2018-06-25 2019-06-24 Process and system for producing para-xylene Ceased WO2020003100A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN201980042977.0A CN112313193B (en) 2018-06-25 2019-06-24 Methods and systems for producing paraxylene
US17/254,351 US11192834B2 (en) 2018-06-25 2019-06-24 Process and system for producing para-xylene
KR1020207034538A KR102783306B1 (en) 2018-06-25 2019-06-24 Method and system for producing para-xylene

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201862689401P 2018-06-25 2018-06-25
US62/689,401 2018-06-25

Publications (1)

Publication Number Publication Date
WO2020003100A1 true WO2020003100A1 (en) 2020-01-02

Family

ID=67660411

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2019/055311 Ceased WO2020003100A1 (en) 2018-06-25 2019-06-24 Process and system for producing para-xylene

Country Status (4)

Country Link
US (1) US11192834B2 (en)
KR (1) KR102783306B1 (en)
CN (1) CN112313193B (en)
WO (1) WO2020003100A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11192834B2 (en) 2018-06-25 2021-12-07 Sabic Global Technologies B.V. Process and system for producing para-xylene

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12491484B2 (en) 2021-01-15 2025-12-09 CRI, hf Reactor for synthesis of methanol or other products
EP4277736A1 (en) 2021-01-15 2023-11-22 Cri Hf Methanol synthesis reactor
US11680209B1 (en) * 2021-12-13 2023-06-20 Uop Llc Process for converting plastic feed containing polypropylene to aromatics

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130296624A1 (en) * 2012-05-07 2013-11-07 Larry L. Iaccino Process for the Production of Xylenes
US20170129828A1 (en) * 2014-06-13 2017-05-11 Sabic Global Technologies B.V. Process for producing benzene from a c5-c12 hydrocarbon mixture
US20180170831A1 (en) * 2016-12-20 2018-06-21 Uop Llc Processes and apparatuses for methylation of aromatics in an aromatics complex

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7265252B1 (en) * 2003-12-18 2007-09-04 Uop Llc Process for xylene production
JP5774122B2 (en) 2010-12-10 2015-09-02 エクソンモービル ケミカル パテンツ インコーポレイテッド Method and apparatus for obtaining aromatic compounds from various raw materials
CN102875317B (en) * 2011-07-12 2014-11-26 中国石油化工股份有限公司 Method for producing p-xylene
WO2013169465A1 (en) 2012-05-07 2013-11-14 Exxonmobil Chemical Patents Inc. Process for the production of xylenes
US8921633B2 (en) 2012-05-07 2014-12-30 Exxonmobil Chemical Patents Inc. Process for the production of xylenes and light olefins
US9926240B2 (en) * 2012-06-05 2018-03-27 Saudi Basic Industries Corporation Process for producing BTX from a C5-C12 hydrocarbon mixture
BR112015008035A2 (en) 2012-10-10 2017-07-04 Gtc Technology Us Llc processes and systems for obtaining aromatics from hydrocarbon catalytic cracking
US9079816B2 (en) 2013-11-19 2015-07-14 Uop Llc Process for producing alkylated aromatic compounds
US9302953B2 (en) 2014-06-30 2016-04-05 Exxonmobil Chemicals Patents Inc. Process for the production of xylenes
CN105295998B (en) * 2014-07-25 2017-08-25 中国石油化工股份有限公司 A kind of method that small molecule aromatic hydrocarbons is produced by diesel raw material
US11192834B2 (en) 2018-06-25 2021-12-07 Sabic Global Technologies B.V. Process and system for producing para-xylene

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130296624A1 (en) * 2012-05-07 2013-11-07 Larry L. Iaccino Process for the Production of Xylenes
US20170129828A1 (en) * 2014-06-13 2017-05-11 Sabic Global Technologies B.V. Process for producing benzene from a c5-c12 hydrocarbon mixture
US20180170831A1 (en) * 2016-12-20 2018-06-21 Uop Llc Processes and apparatuses for methylation of aromatics in an aromatics complex

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
W KAEDING ET AL: "Selective alkylation of toluene with methanol to produce para-Xylene", JOURNAL OF CATALYSIS., vol. 67, no. 1, 1 January 1981 (1981-01-01), US, pages 159 - 174, XP055627031, ISSN: 0021-9517, DOI: 10.1016/0021-9517(81)90269-4 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11192834B2 (en) 2018-06-25 2021-12-07 Sabic Global Technologies B.V. Process and system for producing para-xylene

Also Published As

Publication number Publication date
US11192834B2 (en) 2021-12-07
KR102783306B1 (en) 2025-03-19
US20210323894A1 (en) 2021-10-21
KR20210024452A (en) 2021-03-05
CN112313193B (en) 2023-10-31
CN112313193A (en) 2021-02-02

Similar Documents

Publication Publication Date Title
JP7054743B2 (en) Processes for maximizing the production of xylene from heavy aromatics for use within the process
US9938207B2 (en) Upgrading paraffins to distillates and lube basestocks
US11192834B2 (en) Process and system for producing para-xylene
CN102037102B (en) Novel system for optimising the production of high octane gasoline and the coproduction of aromatic bases
EP3110915B1 (en) Process for producing btx from a c5-c12 hydrocarbon mixture
EP2986584B1 (en) Treating c8-c10 aromatic feed streams to prepare and recover trimethylated benzenes
AU2010313367B2 (en) Process for the conversion of propane and butane to aromatic hydrocarbons
CN112912358A (en) Integrated process for maximizing para-xylene production from full range reformate
EP3155072A1 (en) Process for producing benzene from a c5-c12 hydrocarbon mixture
CN112771137B (en) Process and system for the production of para-xylene and benzene from a stream rich in C6 to C12+ aromatics
CN106661465A (en) Process for producing benzene from C5-C12 hydrocarbon mixture
KR20170095304A (en) Process for conversion of light aliphatic hydrocarbons to aromatics
CN107835847B (en) Process for producing BTX
US10526554B2 (en) Treating C8-C10 aromatic feed streams to prepare and recover trimethylated benzenes
US20220135497A1 (en) Processes for producing aromatic and olefinic compounds
EP3237582A1 (en) Process for producing lpg and btx
US20240309280A1 (en) Integrated processes and systems for producing para-xylenes
EP3157891A1 (en) Process for producing benzene and lpg2
AU2012201167A1 (en) Method of converting C9 aromatics - comprising mixtures to xylene isomers

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19755431

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 20207034538

Country of ref document: KR

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19755431

Country of ref document: EP

Kind code of ref document: A1