Process for the integrated production of naphtha reforming and benzyltoluene

Abstract

A method of integrated naphtha reforming and benzyltoluene production and related systems. The method includes providing a first toluene stream and a chlorine gas stream to a halogenation reactor to produce a benzyl chloride stream and a first HCl effluent stream; then providing the benzyl chloride stream, a second toluene stream, and a Lewis acid stream to an alkylation reactor to produce a benzyltoluene stream and a second HCl effluent stream via a Friedel-Crafts reaction. The method further includes providing naphtha to a catalytic reforming unit to produce a reformed oil stream and a spent catalyst stream, then providing the spent catalyst stream, and at least one of the first HCl effluent stream and the second HCl effluent stream to a catalyst regenerator to regenerate the spent catalyst stream.

Description

Cross-references to related applications

[0001] This application claims the benefit of U.S. Patent Application Serial No. 18 / 530,454, filed December 6, 2023, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] This disclosure relates to an integrated method and related system for the production of naphtha reforming and benzyltoluene. Background Technology

[0003] Aromatic hydrocarbons such as BTX (benzene, toluene, and xylene) and olefins are valuable chemicals commonly used in the production of many materials and the formulation of many consumer products. For example, BTX compounds are frequently used in the processing or production of petroleum products, as well as in the production of consumer products such as paints and varnishes, thinners, fuels, rubber products, adhesives, inks, cosmetics, and pharmaceuticals. Similarly, light olefins are the building blocks of many modern plastic products. One of the most common methods for generating BTX compounds is through naphtha reforming. Therefore, naphtha reforming is often included in hydrocarbon refineries.

[0004] Furthermore, benzyltoluene is one of the most promising hydrogen transport carriers due to its high boiling point, low melting point, low flammability, high flash point, and high hydrogen storage density. Therefore, the demand for benzyltoluene is expected to grow steadily over time. Consequently, benzyltoluene production methods are expected to be increasingly widely used in hydrocarbon refineries.

[0005] Given the current and anticipated increasing demand for these valuable chemicals, there is a desire for efficient production of BTX and benzyltoluene. However, existing refining systems and processes have not maximized the economic synergies offered by process integration. Summary of the Invention

[0006] Therefore, there is a clear and long-standing need to provide an efficient and economical method for producing both BTX and benzyltoluene. The methods and systems disclosed herein address this clear and long-standing need by utilizing a process and system that integrates the two production processes to provide a mutually beneficial utilization of waste streams from one process as feed for the other. Specifically, the regeneration of reforming catalysts used in naphtha reforming requires a stable supply of chlorine, the generation, storage, and / or transportation of which can be costly. However, the integrated method of this disclosure enables the direct transfer of waste HCl to the catalyst regenerator without costly acquisition and / or transportation, and without generating additional carbon dioxide. Similarly, toluene generated as part of naphtha reforming can be directly used in the benzyltoluene production process, thereby eliminating or reducing generation, storage, and / or transportation costs.

[0007] According to one or more embodiments of this disclosure, an integrated method for naphtha reforming and benzyltoluene production is disclosed. The method includes: (i) providing a first toluene stream and a chlorine stream to a halogenation reactor; (ii) operating the halogenation reactor to generate a benzyl chloride stream and a first HCl effluent; (iii) providing the benzyl chloride stream, a second toluene stream, and a Lewis acid stream to an alkylation reactor; (iv) operating the alkylation reactor to generate a benzyl toluene stream and a second HCl effluent via a Friedel-Crafts reaction; (v) providing naphtha to a catalytic reforming unit, wherein a reforming catalyst is disposed within the catalytic reforming unit; (vi) operating the catalytic reforming unit to generate a reformate stream and a spent catalyst stream, the spent catalyst stream representing the used reforming catalyst; (vii) providing the spent catalyst stream and at least one of the first HCl effluent and the second HCl effluent to a catalyst regenerator; (viii) operating the catalyst regenerator to regenerate the reforming catalyst and form a regenerated reforming catalyst stream; and (ix) providing the regenerated reforming catalyst stream as a recycle stream to the catalytic reforming unit.

[0008] In other embodiments, the reformate stream is provided to an aromatics complex to separate and capture benzene, toluene, and mixed xylenes; and the toluene captured in the aromatics complex is provided to at least one of a halogenation reactor and an alkylation reactor to at least partially replace the first toluene stream and the second toluene stream.

[0009] According to one or more embodiments of this disclosure, an integrated system for naphtha reforming and benzyltoluene production is disclosed. The system includes: (i) a catalytic reforming unit including an inlet for receiving a naphtha feed stream, a reforming catalyst disposed within the catalytic reforming unit, and two or more outlets for discharging a spent catalyst stream and a reformed oil stream, wherein the catalytic reforming unit is configured to reform the naphtha feed stream to generate the reformed oil stream and the spent catalyst stream; (ii) a catalyst regenerator fluidly connected to the catalytic reforming unit to receive the spent catalyst stream, wherein the catalyst regenerator is configured to regenerate the spent catalyst; and (iii) a halogenation reactor including an inlet for receiving a first toluene stream, an inlet for receiving a chlorine stream, and an outlet for discharging a first HCl stream. (iv) an efflux stream outlet and an outlet for discharging the benzyl chloride stream; and (v) an alkylation reactor including an inlet for receiving the benzyl chloride stream from the halogenation reactor, an inlet for receiving the Lewis acid stream, an inlet for receiving the second toluene stream, an outlet for discharging the benzyltoluene stream, and an outlet for discharging the second HCl efflux stream, wherein the alkylation reactor operates based on a Friedel-Crafts reaction; and (v) one or more HCl circulation lines fluidly connecting the catalyst regenerator to the halogenation reactor and the alkylation reactor for conveying the first HCl efflux stream and the second HCl efflux stream to the inlet of the catalyst regenerator.

[0010] In other embodiments, the system further includes: an aromatics complex configured to receive the reformate stream and separate the reformate stream into a benzene stream, a third toluene stream, and a mixed xylene stream; and a fluid connection between the halogenation reactor and the alkylation reactor for transferring the third toluene stream from the aromatics complex to at least one of the halogenation reactor and the alkylation reactor to at least partially replace the first toluene stream and the second toluene stream.

[0011] Other features and advantages of the embodiments described herein will be set forth in the detailed description below. Other features and advantages of the embodiments will be apparent in part from the description, or will be recognized by those skilled in the art through practice of the embodiments, including the detailed description below, the accompanying drawings, and the claims. Attached Figure Description

[0012] The following detailed description of specific embodiments of this disclosure is best understood when read in conjunction with the following figures, wherein: Figure 1 This is a schematic diagram of an integrated method for producing naphtha reforming and benzyl toluene according to one or more embodiments of this disclosure; Figure 2 This is a schematic diagram illustrating the generation of benzyl chloride according to one or more embodiments of this disclosure; Figure 3 This is a schematic diagram of benzyltoluene produced according to one or more embodiments of this disclosure; Figure 4 This is a schematic diagram of a catalyst regenerator according to one or more embodiments of this disclosure; Figure 5 This is a schematic diagram of an integrated naphtha reforming and benzyl toluene production method including parallel naphtha reforming units according to one or more embodiments of this disclosure. Figure 6 This is a schematic diagram of an integrated naphtha reforming and benzyl toluene production method including an aromatics complex, according to one or more embodiments of this disclosure; Figure 7 Is it like this? Figure 6 The diagram shows one or more embodiments of an integrated naphtha reforming and benzyltoluene production method that includes a toluene cycle. Figure 8 Is it like this? Figure 6 The diagram shows one or more embodiments of an integrated naphtha reforming and benzyl toluene production method comprising reverse alkylation of benzene and mixed xylenes to produce toluene; and Figure 9 Is it like this? Figure 6 The diagram shown is a schematic representation of one or more embodiments of an integrated naphtha reforming and benzyltoluene production method that includes the hydrogenation of benzyltoluene to produce perhydrobenzyltoluene.

[0013] For the purposes of these simplified diagrams and this description, numerous valves, temperature sensors, electronic controllers, etc., commonly used and well-known to those skilled in the art in certain refining operations are not included. Furthermore, auxiliary components in conventional refining operations, such as air supply, nitrogen supply, hydrogen supply, catalyst hoppers, and flue gas treatment, are not necessarily shown.

[0014] It should also be noted that the arrows in the accompanying drawings refer to pipes, conduits, channels, or other physical transport lines that connect one or more system devices to one or more other system devices via fluid communication. Furthermore, the arrows connecting to system devices define the inlets and outlets within each given system device.

[0015] Reference will now be made in more detail to various embodiments, some of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts. Detailed Implementation

[0016] Implementation details of the integrated method and related system for naphtha reforming and benzyltoluene production disclosed herein will now be provided. While the integrated system for naphtha reforming and benzyltoluene production shown in the included figures is provided as an example, it should be understood that other configurations may be covered by this system and method.

[0017] This disclosure provides an integrated method and system for naphtha reforming and benzyltoluene production. Specifically, the method and system utilize HCl generated as a byproduct in benzyltoluene production for the regeneration of reforming catalysts used in naphtha reforming. The synergistic effect resulting from the integration of different hydrocarbon processing operations reduces the cost, waste, and pollution of each individual process by converting product waste streams into valuable feedstocks.

[0018] In one or more embodiments, the integrated naphtha reforming and benzyltoluene production method includes providing a first toluene stream 101 and a chlorine stream 103 to a halogenation reactor 10, and operating the halogenation reactor 10 to generate a benzyl chloride stream 115 and a first HCl effluent 117. The method further includes providing the benzyl chloride stream 115, a second toluene stream 111, and a Lewis acid stream 113 to an alkylation reactor 20, and operating the alkylation reactor 20 to generate a benzyltoluene stream 125 and a second HCl effluent 127 via a Friedel-Crafts reaction. The method also includes providing naphtha stream 105 to a catalytic reforming unit 30, wherein a reforming catalyst 32 is disposed within the catalytic reforming unit 30. Furthermore, the method includes operating the catalytic reforming unit 30 to generate a reformed oil stream 132 and a spent catalyst stream 134, the spent catalyst stream 134 representing the used reforming catalyst 32. The method further includes providing at least one of the spent catalyst stream 134 and the first HCl effluent stream 117 and the second HCl effluent stream 127 to a catalyst regenerator 40, operating the catalyst regenerator 40 to regenerate the reforming catalyst 32 and form a regenerated reforming catalyst stream 136. Finally, the method includes providing the regenerated reforming catalyst stream 136 as a recycling stream to the catalytic reforming unit 30 to replenish the reforming catalyst 32.

[0019] In one or more embodiments, an integrated system 100 for naphtha reforming and benzyltoluene production includes a catalytic reforming unit 30, which includes an inlet for receiving a naphtha feed stream 105, a reforming catalyst 32 disposed within the catalytic reforming unit 30, and two or more outlets for discharging a waste catalyst stream 134 and a reformed oil stream 132, wherein the catalytic reforming unit 30 is configured to reform the naphtha feed stream 105 to generate the reformed oil stream 132 and the waste catalyst stream 134. The system 100 also includes a catalyst regenerator 40 fluidly connected to the catalytic reforming unit 30 to receive the waste catalyst stream 134, wherein the catalyst regenerator 40 is configured to regenerate the waste catalyst in the waste catalyst stream 132. The system 100 further includes a halogenation reactor 10, which includes an inlet for receiving a first toluene stream 101, an inlet for receiving a chlorine stream 103, an outlet for discharging a first HCl effluent stream 117, and an outlet for discharging a benzyl chloride stream 115. The system 100 further includes an alkylation reactor 20, which includes an inlet for receiving the benzyl chloride stream 115 from the halogenation reactor 10, an inlet for receiving the Lewis acid stream 113, an inlet for receiving the second toluene stream 111, an outlet for discharging the benzyl toluene stream 125, and an outlet for discharging the second HCl effluent stream 127, wherein the alkylation reactor 20 operates based on a Friedel-Crafts reaction. Finally, the system 100 includes one or more HCl circulation lines 138 that fluidly connect the catalyst regenerator 40 to the halogenation reactor 10 and the alkylation reactor 20 for conveying the first HCl effluent stream 117 and the second HCl effluent stream 127 to the inlet of the catalyst regenerator 40.

[0020] Having disclosed the basic operation of the integrated naphtha reforming and benzyltoluene production method and related systems, we now provide in further detail each step and unit operation of the implementation scheme of the integrated method and related systems.

[0021] Formation of benzyltoluene The production of benzyltoluene is typically achieved through a two-step process. In the first step, benzyl chloride is synthesized by reacting toluene with chlorine. Then, in the second step, the benzyl chloride reacts with toluene via Friedel-Crafts alkylation to form benzyltoluene. This disclosure describes such a method and related unit operations, and separately discusses the formation of benzyl chloride and benzyltoluene.

[0022] According to embodiments of this disclosure, benzyl chloride can be generated using any method known to those skilled in the art. Benzyl chloride is typically manufactured on an industrial scale using thermal or photochemical chlorination of toluene. Specifically, irradiation with ultraviolet or beta radiation and an elevated temperature, such as 65°C to 100°C, drives the reaction between toluene and chlorine to generate benzyl chloride. This irradiation causes the chlorine molecule to excite, splitting into two chloride ions that can participate in the reaction with toluene. Specifically, hydrogen is stripped from the methyl group of toluene and replaced by chloride ions. Furthermore, the hydrogen ions removed from the methyl group of toluene can react with the remaining chloride ions to form HCl. The overall reaction is shown in Reaction 1 provided below. This reaction is carried out in a halogenation reactor 10.

[0023]

[0024] Then, according to embodiments of this disclosure, benzyl toluene can be generated from benzyl chloride using any method known to those skilled in the art. The production of benzyl toluene from benzyl chloride is typically carried out via a Friedel-Crafts reaction. Specifically, benzyl chloride reacts with toluene in the presence of a Lewis acid. The overall reaction is shown in reaction 2 provided below. This reaction is carried out in an alkylation reactor 20.

[0025]

[0026] Halogenation reactor Benzyl chloride is generated from toluene and chlorine in halogenation reactor 10. In one or more embodiments, halogenation reactor 10 includes an inlet for receiving a first toluene stream 101, an inlet for receiving a chlorine stream 103, an outlet for discharging a first HCl effluent 117, and an outlet for discharging a benzyl chloride stream 115. It should be understood that, in one or more embodiments, the first HCl effluent 117 and the benzyl chloride stream 115 may be discharged from halogenation reactor 10 as a single stream and subsequently separated by any conventional means known to those skilled in the art to generate separate first HCl effluent 117 and benzyl chloride stream 115. For simplicity, such separation is not shown in the accompanying drawings provided in this disclosure, but is within the understanding of those skilled in the art.

[0027] In one or more embodiments, the halogenation reactor 10 utilizes the thermal chlorination of toluene to generate benzyl chloride. For example, the halogenation reactor 10 may be operated at 65°C to 200°C, 100°C to 200°C, or 65°C to 100°C to excite chlorine gas in the chlorine stream 103 to generate chloride ions for reaction with toluene provided in the first toluene stream 101.

[0028] In one or more embodiments, the halogenation reactor 10 utilizes the photochemical chlorination of toluene to generate benzyl chloride. For example, the halogenation reactor 10 may include a lamp emitting ultraviolet radiation to excite chlorine gas in the chlorine stream 103 to generate chloride ions for reaction with toluene provided in the first toluene stream 101. In various embodiments, the light may be provided by a group of light-emitting diodes (LEDs), a mercury vapor lamp, or other radiation sources. For example, LEDs may emit radiation with wavelengths of 395 nm or 365 nm in the ultraviolet range. Similarly, mercury vapor lamps may emit light with wavelengths ranging from 300 nm to 500 nm, corresponding to the absorption band of chlorine.

[0029] In one or more embodiments, the halogenation reactor 10 operates at a pressure substantially at atmospheric pressure. Operating at atmospheric pressure and temperatures within the range discussed above keeps toluene in a liquid state and chlorine in a gaseous state. However, at other temperatures within the range discussed above, both toluene and chlorine are in the gaseous phase, while benzyl chloride is in the liquid phase. Specifically, benzyl chloride has a boiling point of 179°C and toluene has a boiling point of 110.6°C, thus creating an operating range between their boiling points, within which benzyl chloride is liquid and toluene is gaseous. Under these conditions, benzyl chloride can be removed from the halogenation reactor 10 as it forms and condenses.

[0030] In one or more implementations and reference Figure 2 The halogenation reactor 10 includes a chlorination unit 12 and a toluene recovery unit 14. The chlorination unit 12 converts a first toluene stream 101 into chlorinated compounds in the chlorination unit effluent 119 and HCl in the first HCl effluent 117. The toluene recovery unit 14 receives the chlorination unit effluent 119 from the chlorination unit 12 and separates unreacted toluene 144 from the chlorinated compounds in the chlorination unit effluent 119. The unreacted toluene 144 is recycled back to the chlorination unit 12 as feed, while the chlorinated compounds are discharged for utilization or further processing.

[0031] It should be understood that the reaction of chlorine with toluene to form benzyl chloride may lead to further chlorination of the benzyl chloride to form compounds with higher chlorination degrees, such as benzoyl chloride or trichlorotoluene. To minimize the formation of such compounds with higher chlorination degrees, an excess of toluene relative to the chlorine supplied in the chlorine stream 103 may be provided to the chlorination unit 12. Specifically, the excess toluene causes most of the chlorine to be consumed to form benzyl chloride, thereby minimizing or eliminating the formation of compounds with higher chlorination degrees. Specifically, benzyl chloride is formed first and then reacts with additional Cl2 to form benzoyl chloride. This is a cascade reaction, so consuming more chlorine in the first step limits the second step reaction to form benzoyl chloride. Therefore, in one or more embodiments, the conversion of the toluene stream fed to the chlorination unit 12, comprising both unreacted toluene 144 and the first toluene stream 103, into chlorinated compounds can be limited to 20% to 40% of the toluene feed amount. However, according to various implementation schemes, the collection and recycling of unreacted toluene 144 allows the conversion of the first toluene stream 103 initially provided to chlorination unit 12 to reach 50%, 60%, 70%, 80%, 90%, 50% to 95%, 60% to 95%, 70% to 95%, 80% to 95%, or 85% to 95%.

[0032] In one or more embodiments, the chlorination reactor 12 may operate at the same temperature and pressure as that generally detailed above for the halogenation reactor 10. For example, the chlorination reactor 12 may operate at a temperature of 65 to 100°C and atmospheric pressure.

[0033] The toluene recovery unit 14 receives the chlorination unit effluent 119 from the chlorination unit 12 and separates the unreacted toluene 144 from the chlorinated compounds in the chlorination unit effluent 119. Chlorinated compounds with boiling points higher than toluene are discharged as chlorinated compound stream 146. Furthermore, compounds with boiling points lower than toluene can be discharged from the toluene recovery unit 14 as toluene separation tail gas 142. Toluene separation tail gas 142 mainly contains HCl, therefore no purification of this stream is necessary, as small amounts of hydrocarbons or other chlorinated substances are burned off upon entering the catalyst regenerator 40. Thus, the toluene recovery unit 14 produces toluene separation tail gas stream 142, unreacted toluene 144 stream, and chlorinated compound stream 146.

[0034] The toluene recovery unit 14 may comprise any unit operation or system known to those skilled in the art for separating hydrocarbon streams by vapor pressure. One example of the toluene recovery unit 14 is an atmospheric distillation unit. Atmospheric distillation units utilize fractional distillation, separating the feed stream by heating the feed to a temperature at which one or more fractions in the mixture vaporize while others remain liquid. Furthermore, in various embodiments, the toluene recovery unit 14 may be a simple flash distillation column or a true boiling point distillation column with at least 15 theoretical plates.

[0035] In one or more embodiments, the toluene recovery unit 14 includes multiple separation units. For ease of illustration, the provided... Figure 2 A single unit operation is shown, but it should be understood that such unit operations may include multiple independent separator units to generate the disclosed product stream.

[0036] In one or more embodiments, unreacted toluene 144 is provided to a toluene storage tank 148 to store the unreacted toluene 144 before being transferred to the chlorination unit 12. The toluene storage tank 148 provides a buffer to accommodate rate variations in the recovery of unreacted toluene 144 from the chlorination unit effluent 119, while allowing a stable feed to the chlorination unit 12.

[0037] In one or more embodiments, chlorinated compounds are discharged from toluene recovery unit 14 as chlorinated compound stream 146. Chlorinated compound stream 146 may be provided to benzyl chloride separation unit 16 to separate benzyl chloride to form benzyl chloride stream 115. Specifically, benzyl chloride separation unit 16 may separate benzyl chloride stream 115 from the lighter fraction and higher chlorination fraction 164 of benzyl chloride separation tail gas 162. Benzyl chloride separation tail gas 162 includes fractions with boiling points lower than benzyl chloride, and the higher chlorination fraction 164 includes substances with boiling points higher than benzyl chloride. The higher chlorination fraction may include benzoyl chloride and trichlorotoluene, representing dichloro and trichloro derivatives of toluene, respectively.

[0038] The benzyl chloride separation unit 16 may include any unit operation or system known to those skilled in the art for separating hydrocarbon streams by vapor pressure. An example of the benzyl chloride separation unit 16 is an atmospheric distillation unit. Furthermore, in various embodiments, the benzyl chloride separation unit 16 may be a simple flash distillation column or a true boiling point distillation column having at least 15 theoretical plates. Additionally, in one or more embodiments, the benzyl chloride separation unit 16 includes multiple separation units. For ease of illustration, the provided... Figure 2 A single unit operation is shown, but it should be understood that such unit operations may include multiple independent separator units to generate the disclosed product stream.

[0039] Alkylation reactor Benzyltoluene is generated in alkylation reactor 20 from toluene and benzyl chloride, along with a Lewis acid. In one or more embodiments, alkylation reactor 20 includes an inlet for receiving a benzyl chloride stream 115 from halogenation reactor 10, an inlet for receiving a Lewis acid stream 113, an inlet for receiving a second toluene stream 111, an outlet for discharging a benzyltoluene stream 125, and an outlet for discharging a second HCl effluent stream 127. Furthermore, alkylation reactor 20 operates based on a Friedel-Crafts reaction to generate benzyltoluene stream 125. The mechanism of the Friedel-Crafts reaction is familiar to those skilled in the art, and therefore a detailed description of that mechanism is omitted. It should be understood that in one or more embodiments, the second HCl effluent stream 127 and the benzyltoluene stream 125 may be discharged from alkylation reactor 20 as a single stream, subsequently separated by any conventional method known to those skilled in the art to generate separate second HCl effluent stream 127 and benzyltoluene stream 125. For simplicity, such separation is not shown in the accompanying drawings provided in this disclosure, but is within the understanding of those skilled in the art.

[0040] In one or more implementations and reference Figure 3 The alkylation reactor 20 includes a benzylation unit 22 and a toluene recovery unit 24. The benzylation unit 22 converts benzyl chloride stream 115 into benzyltoluene in the benzylation unit effluent 222 and HCl in the second HCl effluent 127. The toluene recovery unit 24 receives the benzylation unit effluent 222 from the benzylation unit 22 and separates residual toluene 242 from the benzyltoluene in the benzylation unit effluent 222. The residual toluene 242 can be recycled back to the halogenation reactor 10 or the benzylation unit 22 as feed, and the benzyltoluene is discharged as benzyltoluene stream 125 for utilization or further processing.

[0041] In one or more embodiments, the benzylation unit 22, which completes the Friedel-Crafts reaction of benzyl chloride stream 115 to produce benzyltoluene in benzylation unit effluent 222 and HCl in second HCl effluent 127, operates in a temperature range of 50°C to 150°C. In various further embodiments, the benzylation unit 22 may operate at 70°C to 150°C, 90°C to 150°C, 120°C to 140°C, or about 130°C.

[0042] The Friedel-Crafts reaction of benzyl chloride stream 115 to produce benzyltoluene in benzylation unit effluent 222 and HCl in second HCl effluent 127 is carried out in conjunction with the provided Lewis acid stream 113. The Lewis acid acts as a catalyst driving the Friedel-Crafts reaction. In one or more embodiments, Lewis acid stream 113 comprises one or more of ZnCl2, FeCl3, AlCl3, SnCl3, and TiCl4. Therefore, in one or more embodiments, the Lewis acid supplied to alkylation reactor 20 (more specifically, benzylation unit 22) may be selected from ZnCl2, FeCl3, AlCl3, SnCl3, and TiCl4.

[0043] In one or more embodiments, a Lewis acid is provided to the benzylation unit 22 of the alkylation reactor 20 as 50 ppm to 50% by weight of the total feed to the benzylation unit 22. In one or more further embodiments, a solid catalyst is packed in the alkylation reactor 20, thereby eliminating the need for the Lewis acid stream 113.

[0044] To minimize the formation of dibenzyltoluene and other higher products, the total amount of toluene supplied to benzylation unit 22 may be in excess relative to the benzyl chloride supplied in the benzyl chloride stream 115 required to complete the Friedel-Crafts reaction. Specifically, over-alkylation can be a problem because benzyltoluene is more reactive than benzyl chloride and toluene. Alkylation can be controlled by providing excess toluene to consume all the chloride substances.

[0045] The toluene recovery unit 24 may include any unit operation or system known to those skilled in the art for separating hydrocarbon streams by vapor pressure. An example of the toluene recovery unit 24 is an atmospheric distillation unit. Furthermore, in various embodiments, the toluene recovery unit 24 may be a simple flash distillation column or a true boiling point distillation column with at least 15 theoretical plates. The residual toluene 242 removed by the toluene recovery unit 24 may be recycled back to the halogenation reactor 10 or the benzylation unit 22 as feed to reduce the need for fresh toluene in these unit operations.

[0046] In one or more embodiments, the benzylation unit effluent 222 consists primarily of benzyltoluene oligomers and excess toluene, and may contain chlorinated organic compounds such as chlorotoluene, chlorobenzyltoluene, and benzyltoluene oligomers typically bearing one or more chlorine atoms on a benzene ring core. These compounds may be introduced or formed by impurities in benzyl chloride or Lewis acids. After excess toluene is removed in the toluene recovery unit 24, the resulting benzyltoluene stream 125 may be further processed to remove chlorinated organic compounds. For example, benzyltoluene stream 125 may be treated with an alkoxide and heated to a temperature range of 220°C to 320°C with stirring. After dechlorination, a single distillation may be performed to recover benzyltoluene oligomers with low chlorine content. The heavy fraction containing dechlorination agent residue, NaCl, iron salts, and heavy benzyltoluene oligomers is retained as the bottoms of the distillation column.

[0047] Catalytic reforming unit Catalytic reforming is a chemical process used to convert naphtha, typically low-octane oil obtained from crude oil distillation, into a high-octane liquid product called reformate. Reformate is considered a premium blending component for high-octane gasoline. Specifically, catalytic reforming converts low-octane straight-chain hydrocarbons, such as alkanes, into branched-chain alkanes, such as isoalkanes and cycloalkanes, and then partially dehydrogenates them to produce high-octane aromatic hydrocarbons. Therefore, catalytic reforming is commonly included in hydrocarbon refineries.

[0048] In one or more embodiments, the catalytic reforming unit 30 includes an inlet for receiving a naphtha feed stream 105, a reforming catalyst 32 disposed within the catalytic reforming unit 30, and two or more outlets for discharging a spent catalyst stream 134 and a reformed oil stream 132. The catalytic reforming unit 30 is configured to reform the naphtha feed stream 105 to produce a reformed oil stream 132 and to produce a spent catalyst stream 134 as a byproduct of operation.

[0049] In one or more embodiments, the naphtha feed stream 105 is pretreated to remove impurities, contaminants, and other substances that may adversely affect the operation of the catalytic reforming unit 30. Such pretreatment may include hydrotreating or passing through a filter. Given the specific characteristics of the naphtha feed stream 105, such operations are within the understanding of those skilled in the art.

[0050] The operation of the catalytic reforming unit 30 and the specific process parameters of the naphtha feed stream 105 are not within the scope of this disclosure. Specifically, this disclosure relates to integrating naphtha reforming in a broad sense, and related processes for the regeneration of spent catalysts generated as part of naphtha reforming, with the generation of benzyltoluene to achieve synergistic benefits. Therefore, the catalytic reforming unit 30 can operate at the temperature, pressure, liquid hourly space velocity, or other operating parameters required or desired for naphtha catalytic reforming as understood by those skilled in the art.

[0051] The catalytic reforming unit 30 includes a reforming catalyst 32 disposed within the catalytic reforming unit 30. In one or more embodiments, the catalytic bed reactor of the catalytic reforming unit 30 can be operated as a moving bed reactor. In a further embodiment, the catalytic bed reactor of the catalytic reforming unit 30 can be operated as a fixed bed reactor.

[0052] The catalytic reforming unit 30 can operate as a continuous regenerating reformer, a semi-continuous regenerating reformer, or a cyclic regenerating reformer. For the purposes of this disclosure, the continuous regenerating reformer operates continuously, wherein spent catalyst is continuously removed and replaced with regenerated or fresh catalyst; the semi-continuous regenerating reformer operates continuously for a period of time, then stops the naphtha reforming operation and regenerates the catalyst in situ; the cyclic regenerating reformer operates with multiple reactors in parallel, which can be cyclically regenerated offline while keeping the remaining reactors in operation.

[0053] As used herein, “used catalyst” refers to a catalyst that has reacted with naphtha and is at least partially coked. Similarly, as used herein, “regenerated catalyst” refers to a catalyst that has left the catalyst regenerator and is at least partially or substantially free of coke, and “fresh catalyst” refers to a catalyst that has just entered the system and is at least partially or substantially free of coke.

[0054] Catalysts used in naphtha reforming are typically bifunctional, incorporating a metal for dehydrogenation and hydrogenation, as well as an acid-catalyzed isomerization function. The metal sites are provided by platinum and auxiliary metals such as rhenium, tin, germanium, and iridium. Furthermore, alumina supports and chlorides typically provide the acid-catalyzed isomerization function to the catalyst. In one or more embodiments, reforming catalyst 32 is an alumina-supported platinum catalyst. In further embodiments, zeolite and metal catalysts can be used, wherein the zeolite provides the acid sites.

[0055] Catalyst regenerator Catalyst regenerator 40 receives spent catalyst stream 134 and regenerates the spent catalyst to generate regenerated reforming catalyst stream 136. As previously described, reforming catalyst 32 can be regenerated on a continuous or cyclic basis. The purpose of catalyst regeneration is to restore reforming catalyst 32 to a state similar to that of a fresh catalyst, where the metal sites and acidic sites function as before coke deposition. Therefore, catalyst regeneration typically involves controlled burning off of deposited coke, redissolving platinum and promoter metals, and restoring the chloride content of the catalyst.

[0056] In one or more implementations and reference Figure 4The catalyst regenerator 40 can operate in a manner that continuously regenerates the reformer catalyst 32. The catalyst regenerator 40 with continuous regeneration can operate in three different zones: a catalyst regeneration zone, a chlorination zone, and a drying zone. Waste catalyst stream 134 is provided to the top of the catalyst regenerator 40, and the waste catalyst sequentially passes through each zone and is discharged from the bottom of the catalyst regenerator as a regenerated reformer catalyst stream 136.

[0057] The catalyst regeneration zone removes carbonaceous material and coke from the spent catalyst. Carbonaceous material or coke, as an undesirable byproduct of the naphtha reforming process, deposits on the reforming catalyst 32, and the amount of carbonaceous deposit increases with operating time, feed quality, and catalyst state. Consequently, as platinum and acidic sites are covered by coke, catalytic activity and selectivity deteriorate. Therefore, coke removal is necessary during catalyst regeneration. In one or more embodiments, the spent catalyst is heated to a decoking temperature of 500°C to 600°C in an environment with controlled oxygen content to generate a decoking catalyst. For example, in one or more embodiments, a nitrogen stream containing 0.8% to 1.3% oxygen can be provided to provide a controlled oxygen environment for generating the decoking catalyst. Adjustment of temperature and oxygen concentration allows for controlled combustion of catalyst coke during regeneration.

[0058] In one or more embodiments, the spent catalyst stream 134 may pass through a separation hopper (not shown) to remove catalyst fines before being supplied to the catalyst regenerator 40. Furthermore, the transfer of the spent catalyst to the catalyst regenerator 40 includes hydrogen purging of the spent catalyst to remove entrained hydrocarbons and gases, thereby allowing for safe heating and regeneration of the catalyst in the catalyst regenerator 40.

[0059] After decoking, the decoking catalyst is conveyed to the chlorination zone. The chlorination zone redisperses platinum and replenishes chlorine to the alumina support. Even under controlled decoking, metal crystallites within the reforming catalyst 32 may sinter during regeneration. As the diameter of the metal crystallites increases, the activity of the reforming catalyst 32 decreases. Therefore, it is desirable to redisperse metals (such as platinum) through an oxychlorination process. According to this disclosure, organochlorides such as dichloroethane, dichloropropane, or tetrachloroethylene are typically used as precursors to generate HCl and Cl2, rather than directly providing HCl, due to transportation and storage considerations. Taking dichloroethane as an example, HCl is generated as an intermediate product, and chlorine is obtained through Deacon equilibrium. The chlorine then reacts with Pt oxides to form volatiles for redispersibility. However, directly supplying HCl from an HCl circulation line 138 that fluidly connects the catalyst regenerator 40 to the halogenation reactor 10 and the alkylation reactor 20 to transport the first HCl effluent stream 117 and the second HCl effluent stream 127 allows the initial oxychlorination step to be skipped.

[0060] The redistribution of platinum in the reforming catalyst 32 and the replenishment of chlorine to the alumina support are achieved according to reaction 3 in the catalyst regeneration zone of the catalyst regenerator 40 and subsequent reactions 4 and 5 in the chlorination zone of the catalyst regenerator 40. Specifically, platinum oxide is generated according to reaction 3, and Cl2 is generated according to reaction 4. The platinum oxide then reacts with Cl2 to generate the regenerated reforming catalyst. The operating temperature for oxychlorination, which involves reactions 4 and 5 in the chlorination zone of the catalyst regenerator 40, can be 450°C to 550°C, 475°C to 550°C, 450°C to 525°C, 475°C to 525°C, or approximately 500°C.

[0061]

[0062] In one or more embodiments, the reforming catalyst 32 passing through the chlorination zone of the catalyst regenerator 40 is further supplied to the drying zone of the catalyst regenerator 40. The drying zone removes moisture adsorbed on the reforming catalyst 32 before it is recycled back to the catalytic reforming unit 30. Water is a product of reaction 4 and is desired to be removed. Drying is achieved by a flow of nitrogen supplied by nitrogen feed 152. It should be understood that the reforming catalyst 32 moving downwards from the chlorination zone of the catalyst regenerator 40 has a temperature of 450°C to 550°C, therefore the temperature of the drying zone varies with a higher temperature at the inlet and a lower temperature at the outlet.

[0063] It should be understood that omitting the production of HCl from organochlorides such as dichloroethane, dichloropropane, or tetrachloroethylene reduces carbon dioxide emissions from the process, as this conversion generates carbon dioxide as a waste product. Furthermore, supplying HCl from the production of benzyltoluene eliminates the need to purchase HCl, directly reducing costs. Additionally, when continuous regeneration is used, the direct consumption of the waste stream from benzyltoluene production eliminates the need for transportation or storage.

[0064] Naphtha reforming can also be achieved using multiple reactors. Therefore, in one or more embodiments and with reference to... Figure 5 At least two catalytic reforming units 30 and at least two catalyst regenerators 40 can be provided in parallel to allow cyclic operation of each processing column. Specifically, this arrangement allows the first catalytic reforming unit 30A to be operated alternately while regenerating the reforming catalyst 32 of the second catalytic reforming unit 40B, and the second catalytic reforming unit 30B to be operated while regenerating the reforming catalyst 32 of the first catalytic reforming unit 40A.

[0065] Aromatics Complex In one or more implementations and reference Figures 6 to 9The system 100 may include an aromatics complex 60, which is configured to receive reformate stream 132 and separate reformate stream 132 into benzene stream 162, third toluene stream 164 and mixed xylene stream 166.

[0066] Various systems and techniques can be used in the aromatics complex 60 to separate the reformate stream 132 into various fractions, and this disclosure is not inherently intended to be limited to the specific arrangement of the aromatics complex 60. Typically, the aromatics complex 60 produces benzene stream 162, tertiary toluene stream 164, mixed xylene stream 166, and aromatics bottom fraction 168.

[0067] In some embodiments, benzene stream 162 may comprise benzene, which is a cyclic aromatic hydrocarbon with the molecular formula C6H6. In some embodiments, based on the total weight of benzene stream 162, benzene stream 162 may comprise at least 80 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt% of benzene. In some embodiments, third toluene stream 164 may comprise toluene, which is a substituted cyclic aromatic hydrocarbon with the molecular formula C6H5CH3. In some embodiments, based on the total weight of third toluene stream 164, third toluene stream 164 may comprise at least 80 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt% of toluene. In some embodiments, mixed xylene stream 166 may comprise a mixture of xylenes. Xylene is a group of substituted cyclic aromatic hydrocarbons with the molecular formula (CH3)2C6H4. In some embodiments, based on the total weight of mixed xylene stream 166, mixed xylene stream 166 may comprise at least 80 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt% of xylene.

[0068] In one or more embodiments, reformate stream 132 passes through aromatics extraction unit 70 to separate reformate stream 132 into non-aromatic fraction 172 and aromatic fraction 170. Thus, aromatic fraction 170 can be transported to aromatics complex 60 in place of the entire reformate stream 132. Although in Figures 6 to 9 To reduce complexity, non-aromatic hydrocarbon fraction 172 is presented as a single stream; however, it should be understood that non-aromatic hydrocarbon fraction 172 can be further separated into separate streams of various components. Similarly, although in Figures 6 to 9 To reduce complexity, the aromatic hydrocarbon bottom fraction 168 is presented as a single stream, but it should be understood that the aromatic hydrocarbon bottom fraction 168 can be further separated into separate streams of various components.

[0069] In one or more embodiments, the aromatic hydrocarbon fraction 170 may be provided to a clay treatment unit 80 to remove unsaturated hydrocarbons from the aromatic hydrocarbon fraction 170. The clay treatment unit 80 may be operated to purify the aromatic hydrocarbon fraction 170. In one or more embodiments, the clay treatment unit 80 may react non-aromatic olefin compounds via acid-catalyzed alkylation, thereby removing at least non-aromatic olefin compounds from the aromatic hydrocarbon fraction 170. Typically, these non-aromatic olefin compounds may poison downstream units (such as a p-xylene extraction unit) or may reduce the purity of the product aromatic hydrocarbon streams (benzene stream 162, tert-xylene stream 164, and mixed xylene stream 166). The clay treatment unit 80 may function by contacting the aromatic hydrocarbon fraction 170 with a Lewis acid catalyst such as activated clay. The clay treatment unit 80 can contact the aromatic hydrocarbon fraction 170 with a Lewis acid catalyst at temperatures above 165°C, such as above 170°C, above 180°C, 165°C to 250°C, 170°C to 230°C, 180°C to 220°C, 190°C to 210°C, or any subset thereof. The resulting clay-treated stream 182 can be supplied to the aromatics complex 60 in place of the entire reformate stream 132 or the aromatic hydrocarbon fraction 170.

[0070] In one or more embodiments, the clay treatment stream 182 may comprise benzene, toluene, xylene, and C9+ aromatic compounds. In one embodiment, the clay treatment stream 182 may have a lower benzene concentration and a higher toluene and xylene concentration than the aromatic hydrocarbon fraction 170. In one embodiment, based on the total weight of the clay treatment stream 182, the clay treatment stream 182 may comprise at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt% of the total weight of benzene, toluene, xylene, and C9+ aromatic compounds. In one or more embodiments, based on the total weight of the clay treatment stream 182, the clay treatment stream 182 may comprise less than 5 wt%, for example less than 2.5 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.25 wt%, less than 0.1 wt%, less than 0.01 wt%, or even less than 0.001 wt% of olefinic non-aromatic hydrocarbons.

[0071] Aromatics recovery complexes typically have many configurations. In one or more embodiments, the aromatics complex 60 may include, for example, a hexane distillation column that removes lighter components and discharges a bottom product stream. This bottom product stream may be fed to a benzene distillation column, which removes benzene from the top and discharges a bottom stream containing, for example, toluene, mixed xylenes, ethylbenzene, and C9+ aromatic compounds. In some cases, the top effluent may enter an absorption column and a stripping column to purify the benzene. The bottom stream from the benzene distillation column may be treated in the absorption column and stripping column to remove lighter components and further processed in the distillation column. The aforementioned absorption column and stripping column may involve solvent extraction.

[0072] The bottom stream from the benzene distillation column can ultimately be processed in a distillation column to separate and recover toluene and various mixed xylenes. The distillation column may include one or more toluene distillation columns and one or more xylene distillation columns. The toluene distillation column can separate and discharge toluene at the top. The xylene distillation column can receive the bottom effluent from the toluene distillation column, separate and discharge mixed xylenes at the top, and discharge the heavy aromatic hydrocarbon (C9+) bottom stream, such as aromatic hydrocarbon bottom fraction 168.

[0073] In one or more implementations and reference Figure 7 By integrating the aromatics complex 60, toluene captured in the aromatics complex 60 can be supplied to at least one of the halogenation reactor 10 and the alkylation reactor 20. Specifically, supplying a third toluene stream 164 to the halogenation reactor 10 and the alkylation reactor 20 at least partially offsets the toluene demand from the first toluene stream 101 and the second toluene stream 111, respectively. In one or more embodiments, based on the toluene production rate in the aromatics complex 60 and the respective toluene demand of the halogenation reactor 10 and the alkylation reactor 20, the third toluene stream 164 may supply supplemental toluene to only one of the halogenation reactor 10 and the alkylation reactor 20, while the other is supplied by an alternative toluene source. It should be noted that in one or more embodiments, both the halogenation reactor 10 and the alkylation reactor 20 may be supplied by a single toluene feed line, which includes valves and other standard piping equipment to direct a specified flow rate to each of the halogenation reactor 10 and the alkylation reactor 20. The third toluene stream 164 can be mixed with a single toluene feed line, thereby combining all toluene sources delivered to halogenation reactor 10 and alkylation reactor 20.

[0074] Reverse alkyl transfer reactor In one or more implementations and reference Figure 8 At least a portion of the benzene stream 162 and mixed xylene stream 166 captured in the aromatics complex 60 can be provided to the reverse alkyl transfer reactor 90 to convert the benzene and mixed xylenes into toluene. The toluene generated in the reverse alkyl transfer reactor 90 is discharged as alkyl transfer reactor effluent 192.

[0075] In one or more embodiments, the alkyl transfer reactor effluent 192 serves as a feed recycled back to the aromatics complex 60. Specifically, the alkyl transfer reactor effluent 192 is rich in toluene, which can be recovered within the aromatics complex 60. Utilizing the alkyl transfer reactor 90 to generate additional toluene and subsequently recover it in the aromatics complex 60 allows for further integration of naphtha reforming and benzyltoluene production methods, and further reduces the need for supplemental toluene.

[0076] hydrogenation unit In one or more implementations and reference Figure 9 The benzyltoluene stream 125 generated in the alkylation reactor 20 can be provided to the hydrogenation unit 95. The benzyltoluene stream 125 is converted into perhydrobenzyltoluene in the perhydrobenzyltoluene stream 196 by the hydrogenation unit 95.

[0077] In one or more embodiments, hydrogen generated in the catalytic reforming unit 30 can be supplied to the hydrogenation unit 95. Specifically, the operation of the hydrogenation unit 95 requires a hydrogen source, and the naphtha reforming and benzyltoluene production process is further integrated using the hydrogen stream 194 generated as a waste stream during the normal operation of the catalytic reforming unit 30. This treatment reduces or eliminates the need to obtain hydrogen for operating the hydrogenation unit 95.

[0078] It should now be understood that various aspects of the integrated methods and systems for converting crude oil into value-added petrochemical products have been described, and these aspects can be used in combination with various other aspects.

[0079] According to a first aspect, an integrated method for naphtha reforming and benzyltoluene production includes: (i) providing a first toluene stream and a chlorine stream to a halogenation reactor; (ii) operating the halogenation reactor to generate a benzyl chloride stream and a first HCl effluent; (iii) providing the benzyl chloride stream, a second toluene stream, and a Lewis acid stream to an alkylation reactor; (iv) operating the alkylation reactor to generate a benzyltoluene stream and a second HCl effluent via a Friedel-Crafts reaction; (v) providing naphtha to a catalytic reforming unit, wherein a reforming catalyst is disposed within the catalytic reforming unit; (vi) operating the catalytic reforming unit to generate a reformed oil stream and a spent catalyst stream, the spent catalyst stream representing the used reforming catalyst; (vii) providing the spent catalyst stream and at least one of the first HCl effluent and the second HCl effluent to a catalyst regenerator; (viii) operating the catalyst regenerator to regenerate the reforming catalyst and form a regenerated reforming catalyst stream; and (ix) providing the regenerated reforming catalyst stream as a recycling stream to the catalytic reforming unit.

[0080] The second aspect includes the method of the first aspect, wherein both the first HCl effluent and the second HCl effluent are provided to the catalyst regenerator.

[0081] The third aspect includes the method of the first or second aspect, wherein the reformate stream is provided to an aromatics complex to separate and capture benzene, toluene, and mixed xylenes.

[0082] The fourth aspect includes the method of the third aspect, wherein toluene captured in the aromatic complex is provided to at least one of the halogenation reactor and the alkylation reactor to at least partially replace the first toluene stream and the second toluene stream.

[0083] The fifth aspect includes the method of the third aspect, wherein toluene captured in the aromatic complex is provided to both the halogenation reactor and the alkylation reactor to at least partially replace the first toluene stream and the second toluene stream.

[0084] The sixth aspect includes the method of any one of the third to fifth aspects, wherein at least a portion of the benzene and mixed xylenes captured in the aromatic complex is provided to a reverse alkyl transfer reactor to convert the benzene and mixed xylenes into toluene in the alkyl transfer reactor effluent.

[0085] The seventh aspect includes the method of the sixth aspect, wherein the effluent from the alkyl transfer reactor is recycled back to the aromatics complex as feed.

[0086] The eighth aspect includes the method of any one of the first to seventh aspects, wherein the benzyltoluene generated in the alkylation reactor is provided to the hydrogenation unit; hydrogen generated in the catalytic reforming unit is provided to the hydrogenation unit; and the benzyltoluene is converted to perhydrobenzyltoluene.

[0087] The ninth aspect includes the method of any one of the first to eighth aspects, wherein the halogenation reactor generates benzyl chloride by thermal chlorination of toluene.

[0088] The tenth aspect includes the method of any one of the first to ninth aspects, wherein the halogenation reactor generates benzyl chloride by photochemical chlorination of toluene.

[0089] The eleventh aspect includes the method of any one of the first to tenth aspects, wherein the halogenation reactor includes a chlorination unit and a toluene recovery unit, the chlorination unit converting toluene into a chlorinated compound, the toluene recovery unit separating unreacted toluene from the chlorinated compound in the effluent of the chlorination unit; and the unreacted toluene is recycled back to the chlorination unit as feed, thereby achieving a benzyl chloride yield of at least 90% based on the toluene supplied to the halogenation reactor.

[0090] The twelfth aspect includes the method of any one of the first to eleventh aspects, wherein the Lewis acid provided to the alkylation reactor is selected from ZnCl2, FeCl3, AlCl3, SnCl3, and TiCl4.

[0091] The thirteenth aspect includes the method of any one of the first to twelfth aspects, wherein an excess of toluene is provided to the alkylation reactor to consume the chloride material and limit alkylation.

[0092] The fourteenth aspect includes the method of any one of the first to thirteenth aspects, wherein the catalyst regenerator operates in a continuously regenerating manner.

[0093] The fifteenth aspect includes a method of any one of the first to thirteenth aspects, wherein at least two catalytic reforming units and at least two catalyst regenerators are provided in parallel, the method further comprising alternately operating the first catalytic reforming unit while regenerating the reforming catalyst of the second catalytic reforming unit, and operating the second catalytic reforming unit while regenerating the reforming catalyst of the first catalytic reforming unit.

[0094] The sixteenth aspect includes the method of any one of the first to fifteenth aspects, wherein in the catalyst regenerator, the spent catalyst is heated to a decoking temperature of 500°C to 600°C in a nitrogen stream containing 0.8% to 1.3% by weight oxygen to generate a decoking catalyst.

[0095] The seventeenth aspect includes the method of the sixteenth aspect, wherein the reforming catalyst is an alumina-supported platinum catalyst.

[0096] The eighteenth aspect includes the method of the seventeenth aspect, wherein the decoking catalyst is conveyed to the chlorination zone of the catalyst regenerator and mixed with one or both of the first HCl effluent and the second HCl effluent in the presence of oxygen at an operating temperature of 475°C to 525°C to redisperse platinum and replenish chlorine in the alumina support of the reforming catalyst.

[0097] The nineteenth aspect includes a method of any one of the first to eighteenth aspects, wherein the reforming catalyst is further provided to a drying zone of the catalyst regenerator to remove moisture adsorbed on the catalyst before the reforming catalyst is recycled back to the catalytic reforming unit.

[0098] According to the twentieth aspect, an integrated system for naphtha reforming and benzyltoluene production includes: (i) a catalytic reforming unit including an inlet for receiving a naphtha feed stream, a reforming catalyst disposed within the catalytic reforming unit, and two or more outlets for discharging a spent catalyst stream and a reformed oil stream, wherein the catalytic reforming unit is configured to reform the naphtha feed stream to generate the reformed oil stream and the spent catalyst stream; (ii) a catalyst regenerator fluidly connected to the catalytic reforming unit to receive the spent catalyst stream, wherein the catalyst regenerator is configured to regenerate the spent catalyst; and (iii) a halogenation reactor including an inlet for receiving a first toluene stream and a chlorine stream. (iv) an alkylation reactor, including an inlet for receiving the benzyl chloride stream from the halogenation reactor, an inlet for receiving a Lewis acid stream, an inlet for receiving a second toluene stream, an outlet for discharging the benzyltoluene stream, and an outlet for discharging the second HCl stream, wherein the alkylation reactor operates based on a Friedel-Crafts reaction; and (v) one or more HCl circulation lines fluidly connecting the catalyst regenerator to the halogenation reactor and the alkylation reactor for conveying the first HCl stream and the second HCl stream to the inlet of the catalyst regenerator.

[0099] The twenty-first aspect includes the system of the twenty-first aspect, wherein the system further includes an aromatics complex configured to receive the reformate stream and separate the reformate stream into a benzene stream, a third toluene stream and a mixed xylene stream.

[0100] The twenty-second aspect includes the system of the twenty-first aspect, wherein the system further includes a fluid connection between the halogenation reactor and the alkylation reactor for transferring the third toluene stream from the aromatic complex to at least one of the halogenation reactor and the alkylation reactor to at least partially replace the first toluene stream and the second toluene stream.

[0101] It will be apparent to those skilled in the art that various modifications and variations can be made to the described embodiments without departing from the spirit and scope of the claimed subject matter. Therefore, it is intended that this specification cover various modifications and variations to the described embodiments, provided that such modifications and variations are within the scope of the appended claims and their equivalents.

[0102] For the purposes of this disclosure, it is explicitly stated that instructing a stream or effluent to be transported or supplied from one unit to another includes embodiments in which the stream or effluent is transported directly from one unit to another, and embodiments in which there are intermediate systems or units between said units that may substantially alter the composition of the stream or effluent. As used in this disclosure, transporting a stream or effluent “directly” from one unit to another means transporting the stream or effluent from the first unit to the second unit without subjecting the stream or effluent to an intermediate reaction system or separation system that substantially alters the composition of the stream or effluent. Similarly, instructing two systems to be “fluidly connected” indicates that the stream can be transported directly between the systems. Heat transfer devices such as heat exchangers, preheaters, coolers, condensers, or other heat transfer equipment, and pressure devices such as pumps, pressure regulators, compressors, or other pressure equipment are not considered intermediate systems that alter the composition of the stream or effluent. Combining two streams or effluents is also not considered an intermediate system that includes altering the composition of one or both of the combined streams or effluents.

[0103] It should also be understood that a logistics stream can be named after its components, and the components used to name the logistics stream can be the main components of the logistics stream (e.g., 50% to 100% by weight, 70% to 100% by weight, 90% to 100% by weight, 95% to 100% by weight, 99% to 100% by weight, 99.5% to 100% by weight, or even 99.9% to 100% by weight of the contents of the logistics stream). It should also be understood that when a logistics stream containing a certain component is disclosed as being transported from one system component to another system component, the component of that logistics stream is disclosed as being transported from one system component to another system component. For example, a disclosed “hydrocarbon logistics stream” being transported to or from a first system component to a second system component should be understood as equivalently disclosing that “hydrocarbons” are being transported to or from the first system component to the second system component.

[0104] Unless the context clearly specifies otherwise, the singular forms “a” and “the” include plural indicators.

[0105] The scope is provided throughout this disclosure. It is intended that each discrete value covered by the scope be included. Furthermore, it is also intended that a range could be formed by each discrete value covered by the explicitly disclosed scope. For the sake of brevity, this is not explicitly stated after each disclosed scope, but rather this general description is provided herein.

[0106] As used in this disclosure and the appended claims, the terms “comprise,” “has,” and “include,” and all their grammatical variations, are each intended to have an open, non-limiting meaning, not excluding additional elements or steps.

Claims

1. An integrated method for naphtha reforming and benzyltoluene production, the method comprising: (i) The first toluene stream and chlorine stream are supplied to the halogenation reactor; (ii) Operate the halogenation reactor to generate a benzyl chloride stream and a first HCl effluent stream; (iii) The benzyl chloride stream, the second toluene stream, and the Lewis acid stream are fed into the alkylation reactor; (iv) Operate the alkylation reactor to generate a benzyltoluene stream and a second HCl effluent stream via a Friedel-Crafts reaction; (v) Naphtha is supplied to a catalytic reforming unit, wherein a reforming catalyst is disposed within the catalytic reforming unit; (vi) Operate the catalytic reforming unit to generate a reformate stream and a spent catalyst stream, the spent catalyst stream representing the reformate catalyst that has been used; (vii) The waste catalyst stream and at least one of the first HCl effluent stream and the second HCl effluent stream are provided to the catalyst regenerator; (viii) Operate the catalyst regenerator to regenerate the reforming catalyst and form a regenerated reforming catalyst stream; as well as (ix) The regenerated reforming catalyst stream is provided as a recycling stream to the catalytic reforming unit.

2. The method of claim 1, wherein both the first HCl effluent and the second HCl effluent are provided to the catalyst regenerator.

3. The method according to any one of claims 1 to 2, wherein the reformate stream is provided to an aromatics complex to separate and capture benzene, toluene, and mixed xylenes.

4. The method of claim 3, wherein the toluene captured in the aromatics complex is provided to at least one of the halogenation reactor and the alkylation reactor to at least partially replace the first toluene stream and the second toluene stream.

5. The method according to any one of claims 3 to 4, wherein at least a portion of the benzene and mixed xylenes captured in the aromatic complex is provided to a reverse alkyl transfer reactor to convert the benzene and mixed xylenes into toluene in the alkyl transfer reactor effluent.

6. The method of claim 5, wherein the effluent from the alkyl transfer reactor is recycled back to the aromatics complex as feed.

7. The method according to any one of claims 1 to 6, wherein: The benzyltoluene generated in the alkylation reactor is provided to the hydrogenation unit; The hydrogen generated in the catalytic reforming unit is supplied to the hydrogenation unit; and The benzyltoluene was converted to perhydrobenzyltoluene.

8. The method according to any one of claims 1 to 7, wherein: The halogenation reactor includes a chlorination unit and a toluene recovery unit. The chlorination unit converts toluene into a chlorinated compound, and the toluene recovery unit separates unreacted toluene from the chlorinated compound in the effluent from the chlorination unit. The unreacted toluene is recycled back to the chlorination unit as feed.

9. The method according to any one of claims 1 to 8, wherein the Lewis acid supplied to the alkylation reactor is selected from ZnCl2, FeCl3, AlCl3, SnCl3, and TiCl4.

10. The method according to any one of claims 1 to 9, wherein excess toluene is provided to the alkylation reactor to consume the chloride material and limit alkylation.

11. The method according to any one of claims 1 to 10, wherein in the catalyst regenerator, the spent catalyst is heated to a decoking temperature of 500°C to 600°C in a nitrogen stream containing 0.8% to 1.3% by weight oxygen to generate a decoking catalyst.

12. The method of claim 11, wherein the reforming catalyst is an alumina-supported platinum catalyst, and wherein the decoking catalyst is conveyed to the chlorination zone of the catalyst regenerator and mixed with one or both of the first HCl effluent and the second HCl effluent in the presence of oxygen at an operating temperature of 475°C to 525°C to redisperse the platinum and replenish the chlorine in the alumina support of the reforming catalyst.

13. The method of claim 12, wherein the reforming catalyst is further provided to the drying zone of the catalyst regenerator to remove moisture adsorbed on the catalyst before the reforming catalyst is recycled back to the catalytic reforming unit.

14. An integrated system for naphtha reforming and benzyltoluene production, the system comprising: (i) A catalytic reforming unit, including an inlet for receiving a naphtha feed stream, a reforming catalyst disposed within the catalytic reforming unit, and two or more outlets for discharging a waste catalyst stream and a reformed oil stream, wherein the catalytic reforming unit is configured to reform the naphtha feed stream to generate the reformed oil stream and the waste catalyst stream. (ii) A catalyst regenerator fluidly connected to the catalytic reforming unit to receive the spent catalyst stream, wherein the catalyst regenerator is configured to regenerate the spent catalyst; (iii) A halogenation reactor, comprising an inlet for receiving a first toluene stream, an inlet for receiving a chlorine stream, an outlet for discharging a first HCl stream, and an outlet for discharging a benzyl chloride stream. (iv) An alkylation reactor comprising an inlet for receiving the benzyl chloride stream from the halogenation reactor, an inlet for receiving a Lewis acid stream, an inlet for receiving a second toluene stream, an outlet for discharging the benzyl toluene stream, and an outlet for discharging a second HCl effluent stream, wherein the alkylation reactor operates based on a Friedel-Crafts reaction. as well as (v) One or more HCl circulation lines fluidly connecting the catalyst regenerator to the halogenation reactor and the alkylation reactor for conveying the first HCl effluent and the second HCl effluent to the inlet of the catalyst regenerator.

15. The system of claim 14, wherein the system further comprises: An aromatics complex is configured to receive the reformate stream and separate the reformate stream into a benzene stream, a third toluene stream, and a mixed xylene stream; as well as The fluid connection between the halogenation reactor and the alkylation reactor is used to transfer the third toluene stream from the aromatic complex to at least one of the halogenation reactor and the alkylation reactor, so as to at least partially replace the first toluene stream and the second toluene stream.

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