Conversion of synthesis gas to methanol and generation of aromatic compounds by alkylation of toluene

Abstract

The disclosed apparatus and method for generation and conversion comprises / uses a fractionation train (4-6) for producing a xylene fraction (24); a xylene separation unit (10) for processing the xylene fraction to produce a para-xylene extract (39) and a raffinate (40); an isomerization unit (11) for processing the raffinate to produce an isomer of xylene (42) sent to the fractionation train; a synthesis gas generation unit (14; 15) for processing a hydrocarbon feedstock (30) to produce a synthesis gas (34) containing CO and CO2; a methanol synthesis reaction section (50) for processing the synthesis gas (34) to produce methanol (51); and a toluene alkylation reaction section (13) for processing a fraction containing toluene (23) with methanol (51) to produce an alkylated effluent (32) containing xylene sent to the fractionation train.

Description

[Technical Field]

[0001] This invention relates to the production of aromatic compounds (benzene, toluene, and xylene, i.e., BTX) for the petrochemical industry. More specifically, the subject of this invention relates to the production of aromatic compounds (e.g., para-xylene) from the conversion of hydrocarbon compounds (e.g., biomass) into synthesis gas containing CO and CO2.

[0002] An aromatic complex (or apparatus for the conversion of aromatic compounds) is a device that feeds a feedstock called a C6-C10+ feedstock, which mainly consists of 6 to 10 or more carbon atoms. Various sources of aromatic compounds can be introduced into an aromatic complex, the most widely used being obtained from methods for the catalytic reforming of naphtha.

[0003] Within the aromatic complex, regardless of the source of the aromatic compounds, benzene and alkyl aromatic compounds (e.g., toluene, para-xylene, ortho-xylene) are extracted therefrom and then converted to the desired intermediate. The desired products are aromatic compounds having 0 methyl groups (benzene), aromatic compounds having 1 methyl group (toluene), or aromatic compounds having 2 methyl groups (xylene), with para-xylene having the greatest market value among the xylenes in particular.

[0004] The thermal decomposition, oxygen fuel combustion, and gasification methods of hydrocarbon compounds produce a large amount of upgradeable carbon monoxide (CO) and carbon dioxide (CO2). Aromatic compounds are also produced by thermal decomposition methods. If the thermal decomposition is catalytic, a considerable amount of CO2 is also produced by the combustion of coke present on the catalyst used in the thermal decomposition reactor. [Background technology]

[0005] To date, aromatic complexes have made it possible to produce benzene, optionally toluene, and xylene (often para-xylene, sometimes ortho-xylene). Aromatic complexes generally have at least one catalytic unit having at least one of the following functions: - Isomerization of aromatic compounds containing eight carbon atoms, represented by compound A8; enabling the conversion of ortho-xylene, meta-xylene, and ethylbenzene to para-xylene; - Transalkylation; it becomes possible to produce xylene from toluene (and optionally benzene) and A9+ compounds, such as a mixture of trimethylbenzene and tetramethylbenzene; and - Disproportionation of toluene; this makes it possible to produce benzene and xylene.

[0006] The aromatic loop makes it possible to produce high-purity para-xylene through separation by adsorption or by crystallization, an operation well known in the prior art. This “C8 aromatic loop” involves a step of removing heavy compounds (i.e., C9+) in a distillation column known as a “xylene column.” The top flow from this column contains C8 aromatic isomers (i.e., A8 isomers), which are subsequently sent to a method for the separation of para-xylene, which very commonly is a method for separation by pseudo-moving bed (SMB) adsorption, producing extracts and raffinates, or to a crystallization method, in which the para-xylene fraction is isolated in crystalline form from the rest of the mixture's components.

[0007] The extract contains para-xylene, which is then distilled to obtain high-purity para-xylene. The raffinate is rich in meta-xylene, ortho-xylene, and ethylbenzene, which is processed in a catalytic isomerization unit to return a mixture of C8 aromatic compounds in which the proportions of xylene (ortho-, meta-, para-xylene) are substantially in thermodynamic equilibrium and the amount of ethylbenzene is reduced. This mixture is then sent back to the "xylene column" along with fresh feedstock.

[0008] Aromatic complexes that produce benzene and para-xylene are overwhelmingly fed with feedstock derived from oil or natural gas. These complexes do not make it possible to produce bio-based aromatic compounds. Another challenge lies in upgrading carbon in the form of CO and CO2, particularly bio-based carbon, into high-value compounds. The goal of this invention is to overcome these shortcomings. [Overview of the Initiative] [Means for solving the problem]

[0009] (Summary of the invention) In the context described above, the first subject of this description is to overcome the problems of the prior art and to provide a method and apparatus for producing aromatic compounds for the petrochemical industry, enabling the conversion of CO and CO2 (e.g., all of them) produced by pyrolysis or oxygen fuel combustion into additional aromatic compounds. Advantageously, CO2 produced from the combustion of coke present on the catalyst of the pyrolysis method may be converted into aromatic compounds.

[0010] The present invention is based on the conversion of carbon monoxide, i.e., CO, and carbon dioxide, i.e., CO2, into chemical compounds introduced into an aromatic complex, and in particular, on providing a two-step process of multiple units for the conversion of CO and CO2 into aromatic compounds: a step in a methanol synthesis reactor, and then a step in a toluene alkylation reactor. The aromatic compounds resulting from the conversion of CO and CO2, in particular xylene, are processed within the aromatic loop.

[0011] The present invention is therefore based on the conversion of CO and CO2 and the introduction of methanol into an aromatic complex. Specifically, the object of the present invention may consist of providing a pyrolysis unit or an oxygen fuel combustion or gasification unit for producing methanol, and an alkylation reaction section for converting toluene to xylene by reaction with methanol.

[0012] Advantageously, the present invention makes it possible to convert CO and CO2 to desired aromatic compounds, selectively convert toluene to xylene, and remove toluene transalkylation or disproportionation units that are normally present in the aromatic complex in order to convert toluene.

[0013] According to the first aspect, the above-mentioned object is obtained by a method for generating and converting hydrocarbon feedstock, which, along with other advantages, includes the following steps: - A step of fractionating the first hydrocarbon feedstock in a fractionation train; extracting at least one fraction containing benzene, at least one fraction containing toluene, and at least one fraction containing xylene and ethylbenzene; - A step of separating the fraction containing xylene and ethylbenzene in a xylene separation unit to produce an extract containing para-xylene and a raffinate containing ortho-xylene, meta-xylene, and ethylbenzene; - A step of isomerizing a raffinate in an isomerization unit to produce an isomerate rich in para-xylene; - A step of sending the isomerate rich in para-xylene to a fractionation train; - A step of processing a second hydrocarbon feedstock in a synthesis gas production unit, such as a pyrolysis unit, an oxy-fuel combustion unit, etc.; producing a synthesis gas containing at least carbon monoxide (CO) and carbon dioxide (CO2); - A step of processing the synthesis gas in a methanol synthesis reaction section; producing methanol; - A step of alkylating at least a part, preferably all, of a fraction containing toluene with methanol in an alkylation reaction section to produce an alkylation effluent containing xylene; and - A step of sending the effluent containing xylene to a xylene separation unit.

[0014] According to one or more embodiments, the method includes processing methanol in a purification section to separate water and produce purified methanol.

[0015] According to one or more embodiments, the purification section is suitable for separating recycle gas containing unreacted CO and / or unreacted CO2 and recycling the recycle gas to the inlet of the methanol synthesis reaction section.

[0016] One advantage of the present invention is that, in particular, by recycling, all of the synthesis gas can be converted.

[0017] According to one or more embodiments, the synthesis gas production unit includes a pyrolysis unit, which is suitable for producing at least one pyrolysis effluent containing hydrocarbon compounds having 6 to 10 carbon atoms, and this pyrolysis effluent is at least partially fed to the first hydrocarbon feedstock.

[0018] According to one or more embodiments, the method includes supplying supply hydrogen (H2) to the synthesis gas, for example, by a feed line, which is located (directly) upstream of the methanol synthesis reaction section.

[0019] According to one or more embodiments, the synthesis gas production unit includes a pyrolysis unit which comprises at least one reactor used under at least one of the following operating conditions: - Absolute pressure 0.1 MPa ~ 0.5 MPa and HSV 0.01 h -1 ~10h -1 Preferably 0.01h -1 ~5h -1 , more preferably 0.1h -1 ~3h -1 HSV is the ratio of the volumetric flow rate of the feedstock to the volume of the catalyst used. - Temperature 400°C to 1000°C, preferably 400°C to 650°C, preferably 450°C to 600°C, preferably 450°C to 590°C; - Zeolite catalyst; comprising, preferably comprising, at least one zeolite selected from ZSM-5, ferrielite, zeolite beta, zeolite Y, mordenite, ZSM-23, ZSM-57, EU-1 and ZSM-11, and preferably the catalyst is a catalyst comprising only ZSM-5; or The synthesis gas production unit comprises an oxygen fuel combustion unit or a gasification unit, the oxygen fuel combustion unit comprising at least one reactor used under at least one of the following operating conditions: - A reactor used as a fluidized bed reactor; - Temperature 500℃~1000℃; - Pressure 0.1 MPa to 3 MPa, preferably 0.1 MPa to 1 MPa; The gasification unit comprises at least one gasifier used under at least one of the following operating conditions: - Temperature 700℃~1400℃.

[0020] According to one or more embodiments, the methanol synthesis reaction section comprises at least one reactor used under at least one of the following operating conditions: - Temperature: 200°C to 450°C, preferably 220°C to 400°C, more preferably 250°C to 350°C; - Pressure: 1 MPa to 12 MPa, preferably 2 MPa to 10 MPa, more preferably 5 MPa to 10 MPa; - Hydrogen to CO X molar ratio (CO X represents CO and CO2); 3 to 10, preferably 3 to 7, highly preferably 3 to 5; - Space velocity of gas at the inlet of the reactor; 0.2 g / g cata / h to 1 g / g cata / h.

[0021] According to one or more embodiments, the alkylation reaction section comprises at least one alkylation reactor used under at least one of the following operating conditions: - Temperature: 20°C to 550°C; - Pressure: 1 MPa to 10 MPa; - Toluene / methanol molar ratio: 1 to 5; - WHSV 0.5 h -1 to 50 h -1 ; - Presence of a catalyst containing zeolite.

[0022] According to one or more embodiments, the isomerization unit comprises a vapor-phase isomerization zone used under at least one of the following operating conditions: - Temperature: above 300°C; - Pressure: less than 4.0 MPa; - Space-time velocity: less than 10 h -1 ; - Hydrogen to hydrocarbon molar ratio: less than 10; - Presence of a catalyst; the catalyst comprises at least one zeolite having a channel whose opening is defined by a ring containing 10 or 12 oxygen atoms, and at least one group VIIIB metal in a content of 0.1% to 0.3% by weight, including the limit.

[0023] According to one or more embodiments, the isomerization unit includes a liquid-phase isomerization zone used under at least one of the following operating conditions: - Temperature below 300℃; - Pressure less than 4 MPa; - Space-time speed 10h -1 less than; - The presence of a catalyst; the catalyst comprises at least one zeolite having a channel whose opening is defined by a ring containing 10 or 12 oxygen atoms.

[0024] According to a second embodiment, the above-mentioned object is obtained by an apparatus for generating and converting hydrocarbon feedstock, with other advantages, and includes: - Fractionation train; suitable for extracting at least one fraction containing benzene, at least one fraction containing toluene, and at least one fraction containing xylene and ethylbenzene from a first hydrocarbon feedstock; - Xylene separation unit; suitable for processing fractions containing xylene and ethylbenzene to produce an extract containing para-xylene and a raffinate containing ortho-xylene, meta-xylene, and ethylbenzene; - Isomerization unit; suitable for processing raffinate and producing para-xylene-rich isomers; the isomers are sent to the fractionation train; - Synthesis gas production units, such as pyrolysis units or oxygen fuel combustion units; suitable for processing a second hydrocarbon feedstock to produce synthesis gas containing at least carbon monoxide (CO) and carbon dioxide (CO2); - Methanol synthesis reaction section; suitable for converting CO and CO2 of synthesis gas to methanol; and - Alkylation reaction section; suitable for treating at least a portion, preferably all, of a fraction containing toluene with methanol to produce an alkylated effluent containing xylene, particularly para-xylene; the alkylated effluent is sent to a unit for the separation of xylene.

[0025] According to one or more embodiments, the apparatus includes a purification section suitable for processing methanol, separating water and producing purified methanol.

[0026] According to one or more embodiments, the purification section is suitable for separating the recycled gas containing unconverted CO and / or unconverted CO2 and recycling the recycled gas to the inlet of the methanol synthesis reaction section.

[0027] According to one or more embodiments, the synthesis gas production unit includes a pyrolysis unit suitable for producing at least one pyrolysis effluent containing a hydrocarbon compound having 6 to 10 carbon atoms, which is at least partially supplied to a first hydrocarbon feedstock.

[0028] According to one or more embodiments, the apparatus includes a supply line for providing hydrogen to the synthesis gas.

[0029] According to one or more embodiments, the alkylation reaction section is suitable for separating xylene from a water-containing fraction to produce an alkylated effluent.

[0030] According to one or more embodiments, the apparatus further includes a feedstock separation unit that separates a first hydrocarbon feedstock into a hydrocarbon fraction having seven or fewer carbon atoms and an aromatic fraction containing eight or more carbon atoms, the hydrocarbon fraction being sent to a benzene column of a fractionation train and the aromatic fraction being sent to a xylene column of a fractionation train.

[0031] According to one or more embodiments, the apparatus further includes an aromatic compound extraction unit between the feedstock separation unit and the benzene tower, which separates aliphatic compounds from aromatic fractions having seven or fewer carbon atoms and produces an extract that is sent to the benzene tower.

[0032] According to one or more embodiments, the apparatus further includes a stabilization tower, which is suitable for removing volatile species fractions from the effluent of the isomerization unit.

[0033] Embodiments according to the first and second embodiments, as well as other features and advantages of the methods and apparatus according to the above embodiments, will become apparent from reading the following description with reference to the following drawings, but this description is given only as examples and is not limiting. [Modes for carrying out the invention]

[0034] (List of drawings) Figure 1 shows a schematic diagram of the method according to the present invention, which enables increased production of paraxylene and eliminates the need for toluene transalkylation and disproportionation units.

[0035] (Description of the embodiment) Embodiments of the method according to the first aspect and the apparatus according to the second aspect are described in detail here. In the following detailed description, many specific details are disclosed to provide a deeper understanding of the method and apparatus according to the present invention. However, it will be apparent to those skilled in the art that the method and apparatus can be carried out without these specific details. In other cases, well-known features are not described in detail to avoid unnecessarily complicating the description.

[0036] In this patent application, the term "to comprise" is synonymous with "to include" and "to contain," and is inclusive or non-exclusive, not excluding other elements not mentioned. The term "to comprise" is understood to include the exclusive and closed term "to consist of." Furthermore, in this description, an efflux containing compound A essentially or alone corresponds to an efflux containing compound A in an amount of at least 80% by weight or at least 90% by weight, preferably at least 95% by weight, and very preferably at least 99% by weight.

[0037] The present invention may be defined as a method and apparatus comprising a series of unit operations that enable the production of para-xylene and benzene.

[0038] One of the features of the present invention can be summarized as the use of carbon monoxide (CO) and carbon dioxide (CO2), which are products of units for the thermal decomposition, oxygen fuel combustion, or gasification of hydrocarbon compounds, to produce methanol, significantly increasing the amount of aromatic compounds produced by the thermal decomposition, oxygen fuel combustion, or gasification of hydrocarbon compounds, and potentially upgrading all of the resulting CO and CO2.

[0039] The methods and apparatus according to the present invention are characterized in that they use and include catalyst and separation units known to those skilled in the art for producing benzene and para-xylene (these units are commonly encountered in aromatic complexes), that a unit for transalkylation or disproportionation of toluene is not essential, and that they use and include a reaction section for alkylating toluene with methanol to produce xylene. One feature of the present invention is the selective conversion of toluene to a xylene mixture.

[0040] Referring to Figure 1, one or more embodiments of a method and apparatus for the production and conversion of hydrocarbon compounds use and include the following: - Optional feedstock separation unit (1); separates the first hydrocarbon feedstock (2) of the aromatic complex into a hydrocarbon fraction having 7 or fewer carbon atoms (C7-) and an aromatic fraction having 8 or more carbon atoms (A8+); - Optional aromatic compound extraction unit (3); located between feedstock separation unit (1) and fractionation train (4)-(6); separates aliphatic compounds from benzene and toluene in the C7 fraction of the first hydrocarbon feedstock (2); - Fractionation train (4)-(6); located downstream of an optional aromatic compound extraction unit (3); enabling the extraction of benzene, toluene, and xylene from other aromatic compounds; - Xylene separation unit (10) (e.g., of the SMB type using crystallization or molecular sieves and desorbing agents, e.g., toluene); enabling the isolation of para-xylene from xylene and ethylbenzene; - Unit (11) for isomerization of raffinate obtained as effluent from xylene separation unit (10); in particular, for converting ortho-xylene, meta-xylene, and ethylbenzene to para-xylene; - Optional stabilization tower (12); in particular, remove effluent from more volatile species of the aromatic complex (e.g., C5 species), especially from the isomerization unit (11); - A synthesis gas production unit, for example, preferably a contact pyrolysis unit (14), or an oxygen fuel combustion or gasification unit (15); which processes a second hydrocarbon feedstock (30) to produce a synthesis gas (34) containing CO, CO2, and optionally hydrogen and / or water; - Methanol synthesis reaction section (50); processing synthesis gas (34) produced from the pyrolysis unit (14) or the oxygen fuel combustion or gasification unit (15) to produce methanol (51); - A first optional supply line; supplying hydrogen (35) to synthesis gas (34); - Optional purification section (52); process methanol, separate it from a water purge (53) and a recycled gas (54) containing unconverted CO and / or unconverted CO2 to produce purified methanol (55); - Toluene alkylation reaction section (13); The fraction containing toluene, preferably all of the fraction, is alkylated with methanol (51) or purified methanol (55) to produce xylene.

[0041] Advantageously, the methanol synthesis reaction section (50) and the toluene alkylation reaction section (13) allow for the production of excess aromatic compounds from CO and / or CO2 by the addition of methanol (addition of a single carbon atom to each toluene molecule), which gives the possibility of significantly increasing the amount of para-xylene.

[0042] According to one or more embodiments, the purification section (52) is suitable for recycling the recycled gas (54) to the inlet of the methanol synthesis reaction section (50).

[0043] Referring to Figure 1, the feedstock separation unit (1) processes the first hydrocarbon feedstock (2) of the aromatic complex and separates it into a top fraction (16) (C7-) containing (e.g., essentially) compounds having seven or fewer carbon atoms, particularly benzene and toluene, and a bottom fraction (17) (A8+) containing (e.g., essentially) aromatic compounds having eight or more carbon atoms, the bottom fraction (17) is sent to a xylene column (6). According to one or more embodiments, the feedstock separation unit (1) also separates a first toluene fraction (18), which contains at least 90% by weight, preferably at least 95% by weight, and very preferably at least 99% by weight of toluene. According to one or more embodiments, the first toluene fraction (18) is sent to a first column (4), also called a benzene column for distillation of aromatic compounds, and / or a second column (5), also called a toluene column for distillation of aromatic compounds.

[0044] According to one or more embodiments, the first hydrocarbon feedstock (2) is a hydrocarbon fraction mainly containing (i.e., >50% by weight) molecules with carbon atoms ranging from 6 to 10. This feedstock may also contain molecules having more than 10 carbon atoms and / or molecules having 5 carbon atoms.

[0045] The first hydrocarbon feedstock (2) of the aromatic complex is rich in aromatic compounds (e.g., >50% by weight) and contains, preferably, at least 20% by weight, preferably at least 30% by weight, and very preferably at least 40% by weight of benzene relative to the total weight of the first hydrocarbon feedstock (2). The first hydrocarbon feedstock (2) can be produced by catalytic reforming of naphtha or may be the product of cracking units (e.g., steam cracking, contact cracking) or any other means for producing alkyl aromatic compounds.

[0046] According to one or more embodiments, the first hydrocarbon feedstock (2) is at least partially, or even entirely, bio-based. According to one or more embodiments, the first hydrocarbon feedstock (2) is (essentially) derived from a lignocellulosic biomass conversion method. For example, effluents from the conversion of lignocellulosic biomass can be processed to meet the requirements for the first hydrocarbon feedstock (2), and the content of sulfur-based, nitrogen-based, and oxygen-based elements is compatible with the aromatic complex.

[0047] According to one or more embodiments, the first hydrocarbon feedstock (2) of the aromatic complex contains at least 25% by weight, preferably at least 30% by weight, and very preferably at least 35% by weight of pyrolysis effluent (21) relative to the total weight of the first hydrocarbon feedstock (2). According to one or more embodiments, the first hydrocarbon feedstock (2) of the aromatic complex is substantially composed of pyrolysis effluent (21). According to one or more embodiments, the first hydrocarbon feedstock (2) may contain a biobased mixture of aromatic and paraffinic compounds, as well as a non-biobased mixture of aromatic and paraffinic compounds (e.g., resulting from a catalytic reforming unit).

[0048] According to one or more embodiments, the first hydrocarbon feedstock (2) contains less than 10 ppm by weight, preferably less than 5 ppm by weight, and very preferably less than 1 ppm by weight of elemental nitrogen, and / or less than 10 ppm by weight, preferably less than 5 ppm by weight, and very preferably less than 1 ppm by weight of elemental sulfur, and / or less than 100 ppm by weight, preferably less than 50 ppm by weight, and very preferably less than 10 ppm by weight of elemental oxygen.

[0049] According to one or more embodiments, the top fraction (16) from the feedstock separation unit (1) is optionally mixed with the bottom product (benzene and toluene) from the stabilization column (12) defined below, and advantageously sent to a unit (3) for the extraction of aromatic compounds, extracting an effluent (19) containing C6-C7 aliphatic species, which is exported as a co-product from the aromatic complex. The aromatic fraction (20) (essentially benzene and toluene) is called the extract from the aromatic compound extraction unit (3) and is sent to the benzene column (4). According to one or more embodiments, the aromatic fraction (20) is (e.g., essentially) C6-C7 aromatic hydrocarbon feedstock (A6-A7).

[0050] According to one or more embodiments, the fractionation train includes columns (4), (5), (6) and (7) for the distillation of aromatic compounds, enabling the separation of the following four fractions: - Distillate (22); (for example) containing benzene in essence; - Distillate (23); (for example) containing toluene in essence; - Fraction (24); containing (for example, essentially) xylene and ethylbenzene; - Distillates (29); containing aromatic compounds that (for example) essentially contain 9 and 10 carbon atoms.

[0051] The benzene tower (4) is suitable for: processing an aromatic fraction (20), which is (for example, essentially) a C6-C10 aromatic hydrocarbon feedstock (A6+); producing a fraction (22) containing benzene at the top, which may be one of the desired products at the outlet of the aromatic complex; and producing (for example, essentially) a C7-C10 aromatic effluent (27) (A7+) at the bottom.

[0052] The toluene column (5) is suitable for: processing C7-C10 aromatic effluent (27) (A7+), which is the bottom product from the benzene column (4); producing a toluene-containing fraction (23) at the top, which is led to the toluene alkylation reaction unit (13); and producing (essentially) C8-C10 aromatic effluent (28) (A8+) at the bottom.

[0053] A third column (6), also called a xylene column for distillation of aromatic compounds, is suitable for: processing an aromatic fraction (17) (A8+) containing eight or more carbon atoms from the first hydrocarbon feedstock (2), and optionally bottom effluent (28) from the toluene column; producing a fraction (24) at the top containing xylene and ethylbenzene; which is led to a xylene separation unit (10); and producing an effluent at the bottom containing (for example, essentially) C9-C10 aromatic compounds (A9+) (29).

[0054] At the top of the toluene column (5) is a toluene-containing fraction (23), which is sent at least partially, preferably completely, to the toluene alkylation reaction section (13) for reaction with methanol (51) or purified methanol (55) to produce an alkylation effluent (32) containing xylene. Furthermore, a water-containing fraction (31), which is a co-product of the reaction for the alkylation of toluene with methanol, and optionally an oxygen-containing by-product are extracted from the aromatic complex.

[0055] According to one or more embodiments, the toluene alkylation reaction section (13) is fed a mixture (for example, essentially) consisting of toluene and methanol (and optionally water). According to one or more embodiments, toluene is used in excess.

[0056] According to one or more embodiments, the toluene alkylation reaction section (13) comprises at least one alkylation reactor, which is suitable for use under at least one of the following operating conditions: - Temperature range: 20°C to 550°C or 100°C to 500°C, with a preference for 200°C to 450°C, and even more preference for 200°C to 300°C; - Pressure of 1 MPa to 10 MPa or 1 MPa to 8 MPa, preferably 2 MPa to 7 MPa, and more preferably 3 MPa to 5 MPa; - Toluene / methanol molar ratio 1-5, preferably 1-4; - WWH0.5h -1 ~50h -1 Prioritizing 1h -1 ~10h -1 , with a higher priority, 1.5h -1 ~8h -1 .

[0057] The term WWH corresponds to the weight of hydrocarbon feedstock injected per hour relative to the weight of the filled catalyst.

[0058] According to one or more embodiments, the alkylation reactor is operated in the presence of a catalyst containing a zeolite. According to one or more embodiments, the catalyst is based on zeolite ZSM-5, preferably modified by the addition of oxides of various elements (B, Al, Si, P, Zn, Sb, P, and Mg), and more preferably based on phosphorus-containing zeolite ZSM-5.

[0059] According to one or more embodiments, the alkylation reactor is a fixed-bed reactor.

[0060] The alkylated effluent (32) containing xylene obtained from the toluene alkylation reaction section (13) is sent to the xylene separation unit (10). According to one or more embodiments, the alkylated effluent (32) containing xylene obtained from the toluene alkylation reaction section (13) is sent to the toluene column (5). Advantageously, excess toluene is recycled to the toluene column (5) as a component of the alkylated effluent (32) containing xylene. According to one or more embodiments, the alkylated effluent (32) containing xylene obtained from the toluene alkylation reaction section (13) is sent directly to the xylene separation unit (10) if, for example, the toluene content in the alkylated effluent (32) is low (e.g., less than 5% by weight), or if the toluene alkylation reaction section (13) includes a section suitable for separating toluene from xylene.

[0061] The fraction (24) containing xylene and ethylbenzene is processed in the xylene separation unit (10) to produce a fraction or extract (39) containing para-xylene and a raffinate (40). The extract (39) may then be distilled (for example, in the case of separation by SMB adsorption) by an extract column and then an additional toluene column (these are not shown) to obtain high-purity para-xylene, in the case where toluene is used as a desorbent, which is exported as the main product. The raffinate (40) from the xylene separation unit (10) contains (for example, essentially) ortho-xylene, meta-xylene and ethylbenzene and is fed to the isomerization unit (11).

[0062] According to one or more embodiments, the xylene separation unit (10) also separates a second toluene fraction (not shown) containing at least 90% by weight, preferably at least 95% by weight, and very preferably at least 99% by weight of toluene. The second toluene fraction may be, for example, a portion of the toluene used as a desorbent if the xylene separation unit (10) is equipped with an SMB adsorption unit. According to one or more embodiments, the second toluene fraction is sent to a benzene column (4) and / or a second toluene column (5).

[0063] In the isomerization reaction section (not shown) of the isomerization unit (11), isomers of para-xylene are isomerized, while ethylbenzene can be isomerized to give a mixture of C8 aromatic compounds, for example, if it is desired to produce mainly para-xylene; and / or, if it is desired to produce both para-xylene and benzene, it can be dealkylated to produce benzene. According to one or more embodiments, the effluent from the isomerization reaction section is sent to a second separation column (not shown), which at the bottom produces a para-xylene-rich isomer (42), which is preferably recycled to a xylene column (6); and at the top produces a hydrocarbon fraction (43)(C7-) containing compounds with seven or fewer carbon atoms, which is sent to an optional stabilization column (12).

[0064] According to one or more embodiments, the isomerization unit (11) includes a first isomerization zone that operates in the liquid phase and / or a second isomerization zone that operates in the gas phase. According to one or more embodiments, the isomerization unit (11) includes a first isomerization zone that operates in the liquid phase and a second isomerization zone that operates in the gas phase. According to one or more embodiments, a first portion of the raffinate (40) is sent to a liquid-phase isomerization unit to obtain a first isomerized product that is fed directly and at least partially to a separation unit (10), and a second portion of the raffinate (40) is sent to a gas-phase isomerization unit to obtain an isomerized product, which is sent to a xylene column (6).

[0065] According to one or more embodiments, the gas phase isomerization zone is suitable for use under at least one of the following operating conditions: - Temperature above 300°C, preferably 350°C to 480°C; - Pressure less than 4.0 MPa, preferably 0.5 MPa to 2.0 MPa; - Space-time speed 10h -1 Less than (10 liters / liter / hour), preferably 0.5 hours -1 ~6h -1 ; - Hydrogen-to-hydrocarbon molar ratio less than 10, preferably 3-6; - Presence of a catalyst; the catalyst comprises at least one zeolite having a channel whose opening is defined by a ring (10MR or 12MR) containing 10 or 12 oxygen atoms, and at least one group VIIIB metal (reduced form) in a content of 0.1% to 0.3% by weight relative to the total weight of the catalyst, including both limiting values.

[0066] According to one or more embodiments, the liquid phase isomerization zone is suitable for use under at least one of the following operating conditions: - Temperature below 300°C, preferably 200°C to 260°C; - Pressure less than 4 MPa, preferably 2 MPa to 3 MPa; - Space-time velocity (HSV) 10h -1Less than 10 liters / liter / hour, preferably 2 hours -1 ~4h -1 ; - Presence of a catalyst; the catalyst comprises at least one zeolite exhibiting a channel whose opening is defined by a ring having 10 or 12 oxygen atoms (10MR or 12MR), preferably the catalyst comprising at least one zeolite exhibiting a channel whose opening is defined by a ring having 10 oxygen atoms (10MR), and more preferably the catalyst comprising a ZSM-5 type zeolite.

[0067] The term HSV corresponds to the volume of hydrocarbon feedstock injected per unit time relative to the volume of the filled catalyst.

[0068] According to one or more embodiments, an optional stabilization column (12) produces: a stabilized fraction (44) at the bottom containing (e.g., essentially) benzene and toluene; which is optionally recycled to the inlet of a feed material separation unit (1) and / or an aromatic compound extraction unit (3); and a fraction (45) at the top containing more volatile species (e.g., C5-); which is removed from the aromatic complex.

[0069] According to one or more embodiments, the second hydrocarbon feedstock (30) is a mixture of hydrocarbon compounds in which the elemental oxygen content is greater than 1% by weight, preferably greater than 3% by weight, and more preferably greater than 5% by weight, relative to the total weight of the second hydrocarbon feedstock (30). According to one or more embodiments, the second hydrocarbon feedstock (30) includes or consists of lignocellulosic biomass, or one or more components of lignocellulosic biomass selected from the group formed by cellulose, hemicellulose and lignin.

[0070] Lignocellulosic biomass may consist of wood, agricultural waste, or plant waste. Other non-limiting examples of lignocellulosic biomass materials include farm residues (straw, corn stalks and leaves, etc.), forestry residues (products from initial thinning), forestry products, specialized crops (short-term rotational mixed forests), residues from the food processing industry, organic household waste, waste from wood processing plants, waste wood from the construction industry, and recycled or non-recycled paper.

[0071] Lignocellulosic biomass may be derived from by-products of the paper industry, such as kraft lignin, or from black liquor obtained from the production of paper pulp.

[0072] Lignocellulosic biomass may, advantageously, undergo at least one pretreatment step before being introduced into the method according to the present invention. Preferably, the biomass is pulverized and dried until a desired particle size is obtained. Advantageously, a feed material exhibiting a particle size of 0.3 to 0.5 mm can be obtained. Typically, the particle size of the lignocellulosic biomass ranges from a particle size sufficient to pass through a 1 mm sieve to a particle size sufficient to pass through a 30 mm sieve.

[0073] According to one or more embodiments, if the second hydrocarbon feedstock (30) is a solid (e.g., a biomass-type feedstock), the second hydrocarbon feedstock (30) is advantageously loaded into an air entrainment or transport compartment so that it is entrained by an entrainment fluid into the reactor of a pyrolysis or oxygen fuel combustion or gasification furnace. Preferably, the entrainment fluid used is gaseous nitrogen. However, it is also conceivable that other non-oxidizing entrainment fluids may be used. Preferably, the synthesis gas produced during the process may be recycled and used as the entrainment fluid. The synthesis gas mainly consists of non-condensable gaseous effluents and contains at least carbon monoxide (CO) and carbon dioxide (CO2), and optionally / preferably hydrogen (H2), and also advantageously light olefins containing 2 to 4 carbon atoms. In this way, the cost of pyrolysis or oxygen fuel combustion or gasification can be significantly reduced. The second hydrocarbon feedstock (30) may be loaded into a feed hopper or another device that enables the transport of the feedstock into the entrainment compartment in appropriate amounts. In this way, a certain amount of raw material is delivered to the loading area.

[0074] The entrained fluid advantageously transports the second hydrocarbon feedstock (30) from the entrained section through the feedpipe to a reactor or gasifier for pyrolysis or oxygen fuel combustion.

[0075] Typically, the feedpipe is cooled to maintain its temperature at the required level before the second hydrocarbon feed material (30) enters the pyrolysis or oxygen fuel combustion reactor or gasifier. The feedpipe can be cooled by covering the pipe with a jacket, typically air-cooled or liquid-cooled. However, it is also conceivable that the feedpipe may not be cooled.

[0076] According to one or more embodiments, the pyrolysis unit (13) comprises at least one pyrolysis reactor (e.g., a fluidized bed pyrolysis reactor) which is suitable for use under at least one of the following operating conditions:

[0077] According to one or more embodiments, the temperature during the pyrolysis step is 400°C to 1000°C, preferably 400°C to 650°C, preferably 450°C to 600°C, and preferably 450°C to 590°C. In particular, the use of a high-temperature regenerated catalyst produced from a catalyst regeneration step may make it possible to provide a suitable temperature range for the reactor.

[0078] The absolute pressure at which the pyrolysis process is favorable is 0.1 MPa to 0.5 MPa, and the HSV at that pressure is 0.01 h. -1 ~10h -1 Preferably 0.01h -1 ~5h -1 , more preferably 0.1h -1 ~3h -1 HSV is the ratio of the volumetric flow rate of the feedstock to the volume of the catalyst used.

[0079] According to one or more embodiments, the pyrolysis step is catalytic and carried out in the presence of a catalyst. Preferably, the step is operated in the presence of a zeolite catalyst, which comprises, preferably consists of, at least one zeolite selected from ZSM-5, ferrielite, zeolite beta, zeolite Y, mordenite, ZSM-23, ZSM-57, EU-1, and ZSM-11, and preferably the catalyst comprises only ZSM-5. The zeolite used in the catalyst used in the catalytic pyrolysis step may be advantageously doped, preferably with a metal selected from iron, gallium, zinc, and lanthanum.

[0080] Under these conditions, the second hydrocarbon feedstock (30) first undergoes rapid thermal decomposition in the reactor upon contact with the high-temperature catalyst produced from the regenerator. The high-temperature catalyst acts as a heat carrier in this process. The gas obtained from this thermal decomposition then reacts on the catalyst, in which case the catalyst plays a role in catalyzing the reaction that produces the desired chemical intermediate.

[0081] In the pyrolysis unit (14), the second hydrocarbon feedstock (30) is converted in particular into pyrolysis effluent (21) containing hydrocarbon compounds, at least partially, with 6 to 10 carbon atoms. The pyrolysis effluent (21) is preferably supplied to the first hydrocarbon feedstock (2) of the aromatic complex. The pyrolysis unit (14) also produces synthesis gas (34) containing CO, CO2, and optionally hydrogen, as well as by-products (33).

[0082] The product obtained at the end of the pyrolysis process is advantageously recovered in the form of a gaseous effluent containing BTX.

[0083] The gaseous effluent containing the product obtained at the end of the pyrolysis step is then, advantageously, sent to a fractionation section to separate at least the following fractions: - Gaseous fraction of non-condensable gases; containing at least CO and CO2. - A liquid fraction called BTX; it contains hydrocarbon compounds with 6 to 10 carbon atoms. - Liquid fraction; mainly containing compounds with more than 9 carbon atoms, i.e., C9+ compounds, at a minimum of 50% by weight, and - Water.

[0084] The gaseous fraction of the non-condensable gas may, advantageously, include a light olefin containing 2 to 4 carbon atoms.

[0085] The coking catalyst and the unconverted second hydrocarbon feedstock, commonly referred to as "char," are advantageously withdrawn from the reactor and preferably sent to a stripper to remove potentially adsorbed hydrocarbons, thus preventing their combustion in the regenerator. This is done by contacting them with at least one gas selected from steam, an inert gas such as nitrogen, and a portion of the gaseous fraction of non-condensable gases obtained from the gaseous effluent obtained from the pyrolysis process.

[0086] The coking catalyst and the unconverted second hydrocarbon feedstock are, if applicable, stripped and, advantageously, sent to a regenerator, where the coke and char are burned with the addition of air or oxygen, thus producing a regenerated catalyst and a CO2-rich combustion gas.

[0087] According to one or more embodiments, the regenerated catalyst is advantageously recycled to a reactor in the pyrolysis process and undergoes another cycle.

[0088] Advantageously, the thermal decomposition step of the method according to the present invention enables the generation of at least 10% by weight, preferably at least 15% by weight, of aromatic compounds relative to the total mass of the reaction product obtained, and the selectivity is at least 65%, preferably at least 70%, for BTX.

[0089] The pyrolysis process also produces at least one BTX fraction (pyrolysis effluent (21)) and at least one gaseous fraction of a noncondensable gas containing at least CO and CO2 (synthesis gas (34)).

[0090] This method also makes it possible to obtain a heavier liquid fraction in addition to the BTX fraction, which is mainly aromatic and called the "C9+ fraction," and may be advantageously upgraded by external methods compared to the method according to the present invention.

[0091] Preferably, at least a portion of the gaseous fraction of the non-condensable gas is recycled to a reactor in the pyrolysis process, preferably via a compressor. This gaseous flow then acts as a fluid for drawing the feed material into the reactor. In this case, purging of the gaseous recycled effluent is preferably performed either upstream or downstream of the compressor.

[0092] According to one or more embodiments, the pyrolysis effluent (21) is a hydrocarbon fraction primarily containing molecules with 6 to 10 carbon atoms (i.e., >50% by weight). The pyrolysis effluent (21) may also contain molecules having more than 10 carbon atoms and / or molecules having 5 carbon atoms. The pyrolysis effluent (21) is rich in aromatic compounds (e.g., >50% by weight) and, relative to the total weight of the pyrolysis effluent (21), preferably contains at least 20% by weight of benzene, preferredly at least 30% by weight, and very preferably at least 40% by weight of benzene. According to one or more embodiments, the pyrolysis effluent (21) is processed to meet the requirements of the first hydrocarbon feedstock (2) described above, and the content of sulfur-based, nitrogen-based, and oxygen-based elements conforms to the aromatic complex.

[0093] According to one or more embodiments, the synthesis gas (34) (exiting the pyrolysis unit (14)) contains at least a portion of the gaseous fraction of noncondensable gases, and preferably contains at least a portion of CO2-rich combustion gas. According to one or more embodiments, the synthesis gas (34) produced by the pyrolysis unit (14) contains a mixture mainly containing CO and CO2 (e.g., at least 50% by weight). According to one or more embodiments, the synthesis gas (34) contains at least 20% by weight of CO, preferably at least 30% by weight of CO, and very preferably at least 40% by weight of CO (e.g., at least 50% by weight of CO) relative to the total weight of the synthesis gas (34). According to one or more embodiments, the synthesis gas (34) contains at least 0.2% by weight of hydrogen, preferably at least 0.5% by weight of hydrogen, and very preferably at least 0.8% by weight of hydrogen relative to the total weight of the synthesis gas (34). According to one or more embodiments, the synthesis gas (34) contains at least 20% by weight of CO2 relative to the total weight of the synthesis gas (34) at the outlet of the pyrolysis unit (14). According to one or more embodiments, the synthesis gas (34) contains approximately 30% by weight (e.g., ±10% by weight) of CO2 relative to the total weight of the synthesis gas (34) at the outlet of the pyrolysis unit (14). According to one or more embodiments, the synthesis gas (34) also contains methane, ethylene and propylene (e.g., less than 10% by weight) as well as ethane, propane and water (e.g., less than 3% by weight).

[0094] According to one or more embodiments, the by-product (33) comprises a C9+ fraction mainly consisting of more or less alkylated di- and triaromatic compounds. This fraction can be directly upgraded, for example, as bunker fuel, or it can undergo hydrogenation and / or hydrogenation cracking to improve its properties and upgrade it to jet fuel or diesel fuel.

[0095] In the oxygen fuel combustion or gasification unit (15), the second feedstock (30) is converted into a synthesis gas containing CO, CO2 and optionally water.

[0096] According to one or more embodiments, the oxygen fuel combustion unit (15) comprises at least one reactor used under at least one of the following operating conditions: - A reactor used as a fluidized bed reactor; - Temperature 500℃~1000℃; - Pressure of 0.1 MPa to 3 MPa, preferably 0.1 MPa to 1 MPa.

[0097] According to one or more embodiments, the oxygen fuel combustion process is carried out in the presence / injection of a gas source containing at least 80% by weight of oxygen, preferably at least 90% by weight, and very preferably at least 95% by weight, relative to the total weight of the gas source. According to one or more embodiments, the gas source is a high-purity oxygen source, for example, a gas containing at least 99% by weight of oxygen, preferably at least 99.5% by weight, relative to the total weight of the gas source. The temperature of the combustion chamber can be controlled by adjusting the concentration of O2 at the reactor inlet. This adjustment of the O2 concentration can be done by recycling the flue gas.

[0098] According to one or more embodiments, the gasification unit (15) comprises at least one gasifier used under at least one of the following operating conditions: - Temperature 700℃~1400℃.

[0099] According to one or more embodiments, the synthesis gas (34) (exiting the oxygen fuel combustion or gasification unit (15)) comprises a mixture mainly containing CO and CO2 (for example, at least 50% by weight). According to one or more embodiments, the synthesis gas (34) contains at least 70% by weight of CO2, preferably at least 75% by weight, relative to the total weight of the synthesis gas (34). According to one or more embodiments, the synthesis gas (34) contains less than 4% by weight of CO, preferably less than 2% by weight, relative to the total weight of the synthesis gas (34). According to one or more embodiments, the synthesis gas (34) contains water, for example, at least 18% by weight of water, preferably at least 20% by weight, relative to the total weight of the synthesis gas (34).

[0100] According to one or more embodiments, supply hydrogen (35) supplied by a supply line is added to the synthesis gas (34) so ​​that the H2 / (CO+CO2) molar ratio of the synthesis gas (34) is 3 to 10, preferably 3 to 8, preferably 3 to 7, preferably 3 to 6, and very preferably 3 to 5 at the inlet of the methanol synthesis reaction section (50). The supply hydrogen may advantageously be derived from any method for producing hydrogen, such as steam reforming or catalytic reforming, electrolysis of water, or dehydrogenation of alkanes, and its hydrogen purity is typically 75% to 99.9% by volume. It is understood that the supply hydrogen (35) can be supplied directly to the methanol synthesis reaction section (50) and then mixed with the synthesis gas (34).

[0101] In the methanol synthesis reaction section (50), the synthesis gas (34) is preferably enriched with feed hydrogen (35) and converted at least partially to methanol and water. The synthesis reactions of methanol from CO2 and CO are well known to those skilled in the art (see, for example, US5631302, US4238403, EP 3 402 773, and Renewable Energy, 146 (2020), 1192-1203).

[0102] According to one or more embodiments, the methanol synthesis reaction section (50) comprises at least one reactor used under at least one of the following operating conditions: - Temperature range: 200°C to 450°C, with a preference for 220°C to 400°C, and even more preference for 250°C to 350°C; - Pressure range of 1 MPa to 12 MPa, with a preference for 2 MPa to 10 MPa, and a higher preference for 5 MPa to 10 MPa; - H2 / CO X (CO and CO2) molar ratio 3-10, preferably 3-7, very preferably 3-5; - Space velocity of gas at the reactor inlet: 0.2 g / g cata / h~1g / g cata / h.

[0103] According to one or more embodiments, the reactor of the methanol synthesis reaction section (50) is suitable for operation as a fluidized bed or a fixed bed, preferably a fixed bed.

[0104] According to one or more embodiments, the methanol synthesis reaction is carried out in the presence of a hydrogenation catalyst. According to one or more embodiments, the catalyst is a catalyst for the hydrogenation of CO2. According to one or more embodiments, the catalyst for the hydrogenation of CO2 comprises copper (e.g., in the form of an oxide), optionally at least one promoter (e.g., in the form of an oxide) selected from the following elements: Zn, Zr, Si, Al, Ti, Cr, Ga, Ce, and optionally a support (e.g., a refractory oxide, e.g., alumina). According to one or more embodiments, the catalyst for the hydrogenation of CO2 is of the CuO / ZnO / Al2O3 type. According to one or more embodiments, the catalyst for the hydrogenation of CO2 comprises 50-75% by weight of CuO, 15-35% by weight of ZnO, and 5-20% by weight of Al2O3 relative to the total weight of the catalyst.

[0105] According to one or more embodiments, the synthesis gas (34) can be purified before being introduced into the methanol synthesis reaction section (50). The purification of the synthesis gas aims to remove sulfur-containing and nitrogen-containing compounds, halogens, heavy metals, and transition metals. The main techniques for the purification of synthesis gas are adsorption, absorption, and catalytic reactions.

[0106] Various purification methods are well known to those skilled in the art; references may be made, for example, to: Oil & Gas Science and Technology - Rev. IFP Energies Nouvelles, 68 (2013), No. 4 and Applied Energy, 237 (2019), 227-240.

[0107] In an optional purification section (52), methanol (51) is treated to separate water (53) and a recycled gas (54) containing unconverted CO and / or unconverted CO2 to produce purified methanol (55). The recycled gas (54) is preferably recycled to the inlet of the methanol synthesis reaction section (50). Water-methanol separation can be carried out by distillation. According to one or more embodiments, the purified methanol (55) contains a minimum of 99.1% by weight methanol. According to one or more embodiments, water (53) contains a minimum of 99.99% by weight water. Water (53) is a co-product of the methanol synthesis reaction and is either purged and discharged from the method, sent to an electrolytic cell to produce hydrogen, or used upstream of a catalytic pyrolysis unit (14) or an oxygen fuel combustion or gasification unit (15) for biomass pretreatment operations.

[0108] Advantageously, the combination of the methanol synthesis reaction section (50) and the subsequent toluene alkylation reaction section (13) makes it possible to produce additional aromatic compounds from CO and CO2, which are products of the pyrolysis unit (14) or the oxygen fuel combustion or gasification unit (15).

[0109] In this patent application, the groups of chemical elements are given by default according to the CAS classification (CRC Handbook of Chemistry and Physics, published by CRC Press, editor-in-chief DR. Lide, 81st edition, 2000-2001). For example, Group VIIIB according to the CAS classification corresponds to metals from columns 8, 9, and 10 of the new IUPAC classification; Group VIB according to the CAS classification corresponds to metals from column 6 of the new IUPAC classification.

[0110] (Examples) (Example 1 of the reference method) The example of the reference method is used to convert a feedstock containing an aromatic compound mixture obtained from a lignocellulosic biomass conversion method based on catalytic pyrolysis.

[0111] The example of the reference method is similar to the method shown in Figure 1. However, the example of the reference method does not use the following units. - Pyrolysis unit (14); - Methanol synthesis reaction section (50); - Purification section (52); - Toluene alkylation reaction section (13); - Stabilization Tower (12).

[0112] In this example of the reference method, the hydrocarbon feedstock (2) consists of pyrolysis effluent (21).

[0113] The flow rate of aromatic compounds in the supply material (21) at the inlet of the aromatic complex is as follows: - Benzene: 2.63 t / h; - Toluene: 5.64 t / h; - Ethylbenzene: 0.15 t / h; and - Xylene: 3.56 t / h. In other words, a total of 11.98 t / h of aromatic compounds.

[0114] In the reference method, all toluene is converted to benzene and xylene by the disproportionation unit. The xylene feedstock and the disproportionation product are isomerized to give para-xylene, which is then separated by the SMB adsorption unit from the xylene mixture in thermodynamic equilibrium at the outlet of the isomerization unit. This set of unit operations, in the best-case scenario (100% theoretical selectivity for each unit operation), allows for the production of the following compounds: - Benzene: 5.02 t / h; - Para-xylene: 6.96 t / h - Total aromatic compounds: 11.98t / h.

[0115] (Example 2 of the method according to the present invention) The method according to the embodiments of the present invention makes it possible to increase both the total amount of aromatic compounds produced at the same feed rate as in the reference method and the amount of para-xylene.

[0116] The method according to the embodiment of the present invention is similar to the method shown in Figure 1. However, the method according to the embodiment of the present invention does not use a stabilization tower (12).

[0117] Compared to the scheme for referencing methods, the following units are specifically added: - Pyrolysis unit (14); - Methanol synthesis reaction section (50); - Purification section (52); - Toluene alkylation reaction section (13); Toluene is alkylated with methanol.

[0118] According to the method of the embodiment of the present invention, the performance data obtained, using the same second hydrocarbon feedstock (30) and the same unit operation yield as in the embodiment of the reference method, is shown in Table 1 in comparison with that of the reference method.

[0119] [Table 1]

[0120] Table 1 shows that the present invention makes it possible to produce more than 7% of aromatic compounds and more than 20% of para-xylene. The present invention also produces an excess of 83.8 t / h of methanol.

[0121] Therefore, the present invention makes it possible to significantly increase the amount of para-xylene produced and to benefit from the simultaneous production of methanol, which is also an industrially desirable product. [Brief explanation of the drawing]

[0122] [Figure 1] This diagram shows a schematic representation of the method according to the present invention, which enables the production of paraxylene and eliminates the need for toluene transalkylation and disproportionation units.

Claims

1. A method for generating and converting hydrocarbon feedstock, comprising the following steps: - Steps to fractionate the first hydrocarbon feedstock (2) in the fractionation train (4-6); extracting at least one fraction (22) containing benzene, at least one fraction (23) containing toluene, and at least one fraction (24) containing xylene and ethylbenzene; - A step of separating a fraction (24) containing xylene and ethylbenzene in a unit (10) for the separation of xylene, thereby producing an extract (39) containing para-xylene and a raffinate (40) containing ortho-xylene, meta-xylene and ethylbenzene; - A step of isomerizing the raffinate (40) in the isomerization unit (11) to produce a para-xylene-rich isomerized product (42); - A step of sending the para-xylene-rich isomer (42) to the fractionation train (4-6); - A step of processing the second hydrocarbon feedstock (30) in the synthesis gas production unit (14; 15); carbon monoxide (CO) and carbon dioxide (CO) ２ To produce a synthesis gas (34) containing at least ); - A step of treating the synthesis gas (34) in the methanol synthesis reaction section (50); producing methanol (51); - In the toluene alkylation reaction section (13), at least a portion of the toluene-containing fraction (23) is alkylated with methanol (51) to produce an alkylation effluent (32) containing xylene; the alkylation effluent (32) is sent to a unit (10) for the separation of xylene.

2. The method according to claim 1, comprising processing methanol (51) in a purification section (52), separating water (53) to produce purified methanol (55).

3. Unconverted CO and / or unconverted CO in the purification section (52) ２ The method according to claim 2, comprising separating a recycled gas (54) containing and recycling the recycled gas (54) to the inlet of a methanol synthesis reaction section (50).

4. The method according to any one of claims 1 to 3, wherein the synthesis gas generation unit (14; 15) comprises a pyrolysis unit (13) suitable for producing at least one pyrolysis effluent (21) containing a hydrocarbon compound of 6 to 10 carbon atoms, and at least partially feeding the pyrolysis effluent (21) to a first hydrocarbon feedstock (2).

5. The method according to any one of claims 1 to 4, comprising providing supply hydrogen (35) to synthesis gas (34).

6. The synthesis gas generation unit (14; 15) comprises the method according to any one of claims 1 to 5, including: Pyrolysis unit (14); comprising at least one reactor used under at least one of the following operating conditions: - Absolute pressure 0.1 MPa to 0.5 MPa and HSV 0.01 h －１ ~10h －１ Preferably 0.01h －１ ~5h －１ , more preferably 0.1h －１ ~3 hours －１ HSV is the ratio of the volumetric flow rate of the feedstock to the volume of the catalyst used. - Temperature 400°C to 1000°C, preferably 400°C to 650°C, preferably 450°C to 600°C, preferably 450°C to 590°C; - Zeolite catalyst; comprising, preferably comprising, at least one zeolite selected from ZSM-5, ferrielite, zeolite beta, zeolite Y, mordenite, ZSM-23, ZSM-57, EU-1 and ZSM-11, and preferably the catalyst is a catalyst comprising only ZSM-5; or Oxygen fuel combustion unit (15); comprising at least one reactor used under at least one of the following operating conditions: - A reactor operated as a fluidized bed; - Temperature 500℃~1000℃; - Pressure 0.1 MPa to 3 MPa, preferably 0.1 MPa to 1 MPa; or Gasification unit; comprising at least one gasifier used under at least one of the following operating conditions: - Temperature 700℃~1400℃.

7. The methanol synthesis reaction section (50) comprises at least one reactor used under at least one of the following operating conditions, according to any one of claims 1 to 6: - Temperature range: 200°C to 450°C, preferably 220°C to 400°C, and even more preferably 250°C to 350°C; - Pressure range of 1 MPa to 12 MPa, preferably 2 MPa to 10 MPa, and more preferably 5 MPa to 10 MPa; - Hydrogen to CO Ｘ (CO Ｘ represents CO and CO ２ ), molar ratio 3 to 10, preferably 3 to 7, most preferably 3 to 5; - Space velocity of gas at the reactor inlet: 0.2 g / g ｃａｔａ / h ~ 1g / g ｃａｔａ / h.

8. The toluene alkylation reaction section (13) comprises at least one alkylation reactor, which is used under at least one of the following operating conditions, according to any one of claims 1 to 7: - Temperature range: 20°C to 550°C or 100°C to 500°C; - Pressure 1 MPa to 10 MPa; - Toluene / methanol molar ratio 1-5; - WWH0.5h －１ ~50h －１ ; - The presence of a catalyst containing zeolite.

9. The method according to any one of claims 1 to 8, wherein the isomerization unit (11) includes a gas-phase isomerization zone used under at least one of the following operating conditions: - Temperatures exceeding 300°C; - Pressure less than 4.0 MPa; - spatiotemporal speed 10h －１ less than; - Hydrogen-to-hydrocarbon molar ratio less than 10; - Presence of a catalyst; the catalyst comprises at least one zeolite having a channel whose opening is defined by a ring containing 10 or 12 oxygen atoms, and at least one group VIIIIB metal in a content of 0.1% to 0.3% by weight, including the limit.

10. The method according to any one of claims 1 to 9, wherein the isomerization unit (11) includes a liquid-phase isomerization zone used under at least one of the following operating conditions: - Temperature below 300°C; - Pressure less than 4 MPa; - spatiotemporal speed 10h －１ less than; - Presence of a catalyst; the catalyst comprises at least one zeolite having a channel whose opening is defined by a ring containing 10 or 12 oxygen atoms.

11. Apparatus for the production and conversion of hydrocarbon feedstocks, comprising the following: - Fractionation trains (4-6); suitable for extracting from a first hydrocarbon feedstock (2) at least one fraction (22) containing benzene, at least one fraction (23) containing toluene, and at least one fraction (24) containing xylene and ethylbenzene; - Unit (10) for the separation of xylene; suitable for processing a fraction (24) containing xylene and ethylbenzene to produce an extract (39) containing para-xylene and a raffinate (40) containing ortho-xylene, meta-xylene and ethylbenzene; - Isomerization unit (11); suitable for processing raffinate (40) to produce para-xylene-rich isomers (42); isomers (42) are sent to fractionation train (4-6); - Synthesis gas production units (14; 15); suitable for processing a second hydrocarbon feedstock (30) to produce synthesis gas (34) containing at least carbon monoxide and carbon dioxide; - Methanol synthesis reaction section (50); suitable for processing synthesis gas (34) to produce methanol (51); and - Toluene alkylation reaction section (13); suitable for treating at least a portion, preferably all, of the toluene-containing fraction (23) with methanol (51) to produce an alkylated effluent (32) containing xylene; the alkylated effluent (32) is sent to a unit (10) for the separation of xylene.

12. The apparatus according to claim 11, wherein the toluene alkylation reaction section (13) is suitable for separating xylene from a water-containing fraction (31) to produce an alkylated effluent (32).

13. The apparatus according to claim 11 or 12, further comprising a feed material separation unit (1), which separates a feed material (2) into a hydrocarbon fraction (16) having seven or fewer carbon atoms and an aromatic fraction (17) containing eight or more carbon atoms, the hydrocarbon fraction (16) being sent to a benzene column (4) of a fractionation train (4-6), and the aromatic fraction (17) being sent to a xylene column (6) of a fractionation train (4-6).

14. The apparatus according to claim 13, further comprising an aromatic compound extraction unit (3) between the feed material separation unit (1) and the benzene tower (4), which separates aliphatic compounds (19) from an aromatic fraction (16) having seven or fewer carbon atoms and produces an extract (20) to be sent to the benzene tower (4).

15. The converter according to any one of claims 11 to 14, further comprising a stabilization tower (12), which is suitable for removing volatile species fractions (45) from the effluent of the isomerization unit (11).

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