Method for producing aromatic compounds

Abstract

To provide a method for selectively and efficiently producing benzene and toluene at the same time as aromatic compounds by using heavy aromatic hydrocarbon compounds as the raw material .SOLUTION: A method for producing aromatic compounds can produce benzene and toluene at the same time when producing aromatic compounds by bringing heavy aromatic hydrocarbon compounds belonging to aromatic hydrocarbon compounds with a carbon number of 8-15 and a boiling point range of 130-250°C and aliphatic hydrocarbon compounds into contact with catalysts including 10-membered and / or 12-membered ring pore zeolites.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for producing an aromatic compound that simultaneously produces benzene and toluene, and more particularly, to a method for producing an aromatic compound excellent in selectivity and efficiency for simultaneously producing benzene and toluene, which enables efficient lightening of heavy aromatic hydrocarbon compounds by carrying out the reaction in the presence of an aliphatic hydrocarbon compound even in a catalytic contact reaction using a heavy aromatic hydrocarbon compound as a raw material.

Background Art

[0002] Heavy aromatic hydrocarbons have few industrial applications and low value, so processes for converting them into benzene, toluene, xylene and the like are becoming increasingly important. Accordingly, methods for producing benzene, toluene, and xylene from heavy aromatic hydrocarbons by adding hydrogen have been proposed (see, for example, Patent Documents 1 to 4). Furthermore, methods for producing xylene from heavy aromatic hydrocarbons through transalkylation have been proposed (see, for example, Patent Documents 5 to 6).

Prior Art Literature

Patent Literature

[0003]

Patent Literature 1

Patent Literature 2

Patent Literature 3

Patent Literature 4

Patent Literature 5

Patent Literature 6

Summary of the Invention

Problem to be Solved by the Invention

[0004] However, the proposals in Patent Documents 1 to 4 have a wide range of applications and require hydrogen, which has become increasingly important in recent years, in a molar ratio equal to or greater than that of the raw materials, indicating room for improvement. Furthermore, the methods proposed in Patent Documents 5 to 6 are limited to using ethylbenzene as a raw material, and other heavy aromatic hydrocarbon compounds have not been considered. In addition, the product is xylene, which belongs to the category of heavy aromatic hydrocarbon compounds, and lighter compounds such as benzene and toluene have not been considered.

[0005] Therefore, there was a growing expectation for the emergence of methods that would not require precious hydrogen, but instead use heavy aromatic hydrocarbon compounds as raw materials, and produce aromatic compounds, particularly highly useful ones such as benzene and toluene. [Means for solving the problem]

[0006] As a result of diligent research to solve the above problems, the present inventors have discovered a method for producing aromatic compounds in which benzene and toluene can be produced simultaneously even without hydrogenation by contacting a heavy aromatic hydrocarbon compound with a catalyst to produce a lighter aromatic hydrocarbon compound, using a catalyst containing a specific zeolite and including an aliphatic hydrocarbon compound. This has led to the completion of the present invention.

[0007] In other words, the present invention relates to a method for producing aromatic compounds, characterized by simultaneously producing benzene and toluene when producing aromatic compounds by contacting a heavy aromatic hydrocarbon compound belonging to aromatic hydrocarbon compounds with 8 to 15 carbon atoms and a boiling point range of 130 to 250°C with an aliphatic hydrocarbon compound in a catalyst containing a 10-membered ring and / or 12-membered ring pore zeolite.

[0008] The present invention will be described in detail below.

[0009] The present invention provides a method for producing aromatic compounds by contacting a heavy aromatic hydrocarbon compound and an aliphatic hydrocarbon compound with a catalyst containing a 10-membered ring and / or 12-membered ring pore zeolite, thereby efficiently lightening the heavy aromatic hydrocarbon compound and simultaneously producing highly useful benzene and toluene.

[0010] The aliphatic hydrocarbon compound used in this process is not particularly limited as long as it belongs to the category of aliphatic hydrocarbon compounds. In particular, it is preferable to use an aliphatic hydrocarbon compound having 4 to 10 carbon atoms, as this method allows for the efficient simultaneous production of benzene and toluene. Examples include paraffinic compounds such as butane, pentane, hexane, heptane, and octane; olefinic compounds such as butene, pentene, hexene, heptane, and octane; and alicyclic compounds such as cyclopropane, cyclobutane, cyclopentane, methylcyclopentane, and cyclohexane. Among these, aliphatic hydrocarbon compounds having 4 to 9 carbon atoms are preferred because they allow for the selective and efficient production of benzene. Specifically, examples include paraffinic compounds such as butane, hexane, heptane, octane, and nonane; olefinic compounds such as butene, pentene, hexene, heptane, octane, and nonene; and alicyclic compounds such as cyclobutane, cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, and mixtures thereof.

[0011] These aliphatic hydrocarbon compounds may be petroleum-derived, such as naphtha, plant-derived, such as bioethanol and bionaphtha, or derived from chemical recycling of resins, such as polyolefins, polyvinyl chloride, acrylics, and polystyrene.

[0012] Furthermore, heavy aromatic hydrocarbon compounds belong to the category of aromatic hydrocarbon compounds with 8 to 15 carbon atoms and a boiling point of 130 to 250°C. Examples include monocyclic aromatic compounds with a paraffin alkyl group such as ethylbenzene, cumene, xylene, and triisopropylbenzene; monocyclic aromatic compounds with an olefin alkyl group such as styrene, allylbenzene, and divinylbenzene; and polycyclic aromatic hydrocarbon compounds such as indan and indene. Among these, monocyclic aromatic compounds with an alkyl group having 8 to 15 carbon atoms are preferred because they can selectively and efficiently produce benzene and toluene. Specifically, examples include monocyclic aromatic compounds with a paraffin alkyl group such as ethylbenzene, cumene, xylene, and triisopropylbenzene; and monocyclic aromatic compounds with an olefin alkyl group such as styrene, allylbenzene, and divinylbenzene. However, if the aromatic hydrocarbon compound has fewer than 8 carbon atoms or a boiling point below 130°C, the raw material will have a small number of carbon atoms, making it less efficient as a method for producing aromatic compounds that can simultaneously produce benzene and toluene. On the other hand, in the case of aromatic hydrocarbon compounds with more than 15 carbon atoms or a boiling point exceeding 250°C, the formation of coke due to side reactions during the reaction, and the decrease in the production ratio of light components such as benzene and toluene become significant, resulting in inferior production efficiency.

[0013] In the present invention's method for producing aromatic compounds, when simultaneously producing benzene and toluene using heavy aromatic hydrocarbon compounds as raw materials, an aliphatic hydrocarbon compound is used as a raw material at the same time, thereby enabling the production of aromatic compounds without requiring highly useful hydrogen.

[0014] The supply ratio of heavy aromatic hydrocarbon compounds to aliphatic hydrocarbon compounds as raw materials is arbitrary, and since this is an efficient manufacturing method that suppresses the formation of coke and the like, the supply ratio of heavy aromatic hydrocarbon compounds to aliphatic hydrocarbon compounds as raw materials is preferably 90 / 10 to 10 / 90 by weight, and particularly preferably 50 / 50 to 10 / 90.

[0015] Furthermore, the aromatic compound produced in this process preferably contains benzene and toluene, and is a lighter aromatic hydrocarbon compound than the heavy aromatic hydrocarbon compound used as the raw material, with benzene and toluene as its main components.

[0016] Benzene and toluene, which belong to the light aromatic hydrocarbon compounds, have high utility as solvents and raw materials for aromatic compounds.

[0017] In the method for producing aromatic compounds of the present invention, a catalyst containing a 10-membered ring and / or 12-membered ring pore zeolite is used as the catalyst. The 10-membered ring and / or 12-membered ring pore zeolite can be any type belonging to that category, for example, 10-membered ring pore zeolites such as AEL type, EUO type, FER type, HEU type, MEU type, MEL type, MFI type, and NES type; and 12-membered ring pore zeolites such as AFI type, MTW type, VFI type, FAU type, *BEA type, and MWW type. Among these, a 10-membered ring pore zeolite is particularly preferred because it enables the efficient production of aromatic compounds, and an MFI type zeolite is particularly preferred. For example, zeolites such as MFI type, *BEA type, and MWW type refer to aluminosilicate compounds belonging to the structural codes MFI, *BEA, MWW, etc., as defined by the International Zeolite Society. Furthermore, in such cases, the zeolite may contain metals, and examples of the metals include at least one selected from silver, calcium, magnesium, strontium, barium, gallium, and zinc, with zinc and / or gallium being particularly preferred. However, if the zeolite is one other than a 10-membered ring pore zeolite or a 12-membered ring pore zeolite, or if it contains components other than the 10-membered ring and / or 12-membered ring pore zeolite, problems such as low selectivity for aromatic compounds and significant coke formation are likely to occur.

[0018] Further, the shape of the catalyst may be powdery, granular, cylindrical, triangular prismatic, quadrangular prismatic, polygonal prismatic, or may be a hollow shape of any of the foregoing; furthermore, it may be an irregular / regular shape having a honeycomb structure, cylindrical shape, independent pores or communicating pores, and when formed into such a shape, the catalyst may contain a binder or the like.

[0019] When producing an aromatic compound by bringing a heavy aromatic hydrocarbon compound and an aliphatic hydrocarbon compound into contact with a catalyst, there are no limitations on the contact reaction conditions provided that an aromatic compound containing both benzene and toluene can be produced. In particular, a reaction temperature in the range of 300 to 600°C is preferable because this can suppress the generation of by-produced paraffin, olefin or alkane, eliminates the need for an unnecessarily heat-resistant reaction apparatus, and enables efficient production of aromatic compounds. There is also no limitation on the reaction pressure, and for example, operation in a pressure range of 0.05 to 1 MPa is preferable. The supply of the aliphatic hydrocarbon compound and the heavy aromatic hydrocarbon compound, which are reaction raw materials, to the catalyst at this time is not particularly limited in terms of the ratio of the volume of the raw material gas to the volume of the catalyst, for example, 0.1 h -1 ~50000h -1 A space velocity of this order can be mentioned.

[0020] Further, when supplying a mixed raw material of a heavy aromatic hydrocarbon compound and an added aliphatic hydrocarbon compound as a gas, it can be used as a single gas, a mixed gas, or a product obtained by diluting these with a single or mixed gas selected from inert gases such as nitrogen, carbon monoxide, and carbon dioxide.

[0021] There are no limitations on either the contact reaction mode or the reactor for producing the aromatic compound, and for example, a fixed bed, a fluidized bed, or a combination thereof may be used. Further, the reactor may be a single-tube reactor or a multi-tube reactor.

[0022] In the method for producing an aromatic compound of the present invention, incidental steps such as a step of separating and purifying a product containing an aromatic compound, particularly a step of separating and purifying benzene and toluene, can be added as appropriate.

Effects of the Invention

[0023] This invention provides a method for producing aromatic compounds that exhibits excellent selectivity and efficiency in the simultaneous production of benzene and toluene even in catalytic reactions with catalysts using heavy aromatic hydrocarbon compounds as raw materials, and is therefore extremely useful industrially. [Examples]

[0024] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[0025] The evaluation method used in the examples is described below.

[0026] ~Analysis of reaction products~ The gaseous components after the reaction were analyzed using a gas chromatograph equipped with a TCD detector (Shimadzu Corporation, product name GC-14B) and a gas chromatograph equipped with an FID detector (Shimadzu Corporation, product name GC-14A). The packing material for the gas chromatograph equipped with a TCD detector (Shimadzu Corporation, product name GC-14B) was MS-5A (GL Sciences Co., Ltd.). The separation column for the gas chromatograph equipped with an FID detector (Shimadzu Corporation, product name GC-14A) was CP-Al2O3 / KCl (Agilent Technologies, Ltd.). The liquid components were analyzed using a gas chromatograph equipped with an FID detector (Shimadzu Corporation, product name GC-2025). The separation column used was TC-1 (GL Sciences Co., Ltd.).

[0027] Preparation Example 1 (Preparation of Catalyst) 100 parts by weight of 10-membered ring-pore zeolite (manufactured by Tosoh Corporation, product name HSZ-840HOA; Si / Al2 ratio = 40, MFI type) was mixed with 43 parts by weight of silica (manufactured by Nissan Chemical Industries, product name Snowtex N-30G), 4 parts by weight of cellulose, and 30 parts by weight of pure water. The mixture was then molded into cylindrical bodies with a diameter of 1.5 mm and a length of 1.0 to 7.0 mm (average length 3.5 mm), and these were dried overnight at 100°C to prepare the catalyst.

[0028] Preparation Example 2 (Preparation of Catalyst) The catalyst was prepared in the same manner as in Preparation Example 1, except that a 12-membered ring-pore zeolite (Tosoh Corporation, product name HSZ-940HOA; Si / Al2 ratio = 40, *BEA type) was used instead of a 10-membered ring-pore zeolite (Tosoh Corporation, product name HSZ-840HOA; Si / Al2 ratio = 40, MFI type).

[0029] Preparation Example 3 (Preparation of Catalyst) The catalyst was prepared in the same manner as in Preparation Example 1, except that a 10-membered ring-pore zeolite (Tosoh Corporation, product name HSZ-870HOA; Si / Al2 ratio = 200; MFI type) was used instead of a 10-membered ring-pore zeolite (Tosoh Corporation, product name HSZ-840HOA; Si / Al2 ratio = 40; MFI type).

[0030] Preparation Example 4 (Manufacturing of Molded Articles) A molded article was obtained in the same manner as in Preparation Example 1, except that SAPO-34 (CHA-type zeolite (8-membered ring zeolite), Si / Al2 ratio = 1.5) prepared in reference to Microporous and Mesoporous Materials 152 (2012) 178-184 was used.

[0031] Preparation Example 5 (Preparation of Catalyst) To 100 parts by weight of the catalyst obtained in Preparation Example 1, 2.54 parts by weight of zinc acetate dihydrate (manufactured by Fujifilm Wako Pure Chemical Industries) and 124 parts by weight of pure water were added and the mixture was stirred. Next, 100 parts by weight of the catalyst obtained in Preparation Example 1 was added to the solution and allowed to stand for 30 minutes. After that, the precipitate was dried at 110°C for 2 hours and then calcined at 550°C for 5 hours to prepare a zinc-containing catalyst.

[0032] Example 1 In a fixed-bed gas-phase flow reactor, 3.75 g of the catalyst obtained in Preparation Example 1 was packed into the middle section of a stainless steel reaction tube (16 mm inner diameter, 600 mm length). The temperature was raised to 525°C while circulating air at 50 ml / min, and then the flowing gas was switched to nitrogen at 50 ml / min. A ceramic tubular furnace was used to control the temperature of the catalyst layer during this heating process.

[0033] As raw materials, a mixture of aliphatic hydrocarbon compounds (a mixed solution of methylcyclopentane 40% by weight, hexane 24% by weight, cyclohexane 10% by weight, pentane 8% by weight, methylcyclohexane 6% by weight, heptane 4% by weight, ethylcyclohexane 2% by weight, octane 2% by weight, and nonane 1% by weight) and heavy aromatic hydrocarbon compounds (a mixture of styrene 30% by weight, allylbenzene 20% by weight, ethylbenzene 20% by weight, triisopropylbenzene 20% by weight, and indan 10% by weight) was mixed in a weight ratio of 1:1 and tested at a space velocity of 1.56 h. -1 Aromatic compounds were produced by supplying nitrogen at a flow rate of 50 ml / min along with a reaction pressure of 0.1 MPa. The products were analyzed by gas chromatography. The results are shown in Table 1.

[0034] Example 2 Aromatic compounds were produced in the same manner as in Example 1, except that the catalyst obtained in Preparation Example 2 was used. The results are shown in Table 1.

[0035] Example 3 Aromatic compounds were produced in the same manner as in Example 1, except that the catalyst obtained in Preparation Example 3 was used. The results are shown in Table 1.

[0036] Example 4 Aromatic compounds were produced in the same manner as in Example 1, except that a mixed raw material consisting of an aliphatic hydrocarbon compound and a heavy aromatic hydrocarbon compound in a weight ratio of 1:3 was supplied as the raw material. The results are shown in Table 1.

[0037] Example 5 Aromatic compounds were produced in the same manner as in Example 1, except that a mixed raw material consisting of an aliphatic hydrocarbon compound and a heavy aromatic hydrocarbon compound in a weight ratio of 1:9 was supplied as the raw material. The results are shown in Table 1.

[0038] Example 6 The aromatic compound was produced in the same manner as in Example 1, except that the reaction pressure was set to 0.6 MPa. The results are shown in Table 1.

[0039] Example 7 Aromatic compounds were produced in the same manner as in Example 1, except that the catalyst obtained in Preparation Example 5 was used. The results are shown in Table 1.

[0040] Comparative Example 1 Aromatic compounds were produced in the same manner as in Example 1, except that aliphatic hydrocarbon compounds were not used and only heavy aromatic hydrocarbon compounds were used as raw materials. The results are shown in Table 2. A large amount of coke was produced, which can be a factor in the decrease of catalytic activity.

[0041] Comparative Example 2 Aromatic compounds were produced using the same method as in Example 1, except that heavy aromatic hydrocarbon compounds were not used and only aliphatic hydrocarbon compounds were used as raw materials. The results are shown in Table 2. The production efficiency of aromatic compounds, including benzene and toluene, was inferior.

[0042] Comparative Example 3 Aromatic compounds were produced in the same manner as in Example 1, except that the molded article obtained in Preparation Example 4 was used. The results are shown in Table 2. The conversion rate was low, resulting in poor production efficiency of aromatic compounds and a large amount of coke formation, which can be a factor in reducing catalytic activity.

[0043] Comparative Example 4 Aromatic compounds were produced in the same manner as in Example 1, except that SiO2 (manufactured by Fuji Silycia, trade name Q-6) was used as a molded powder instead of the catalyst obtained in Preparation Example 1. The results are shown in Table 2. The conversion rate was low, resulting in poor production efficiency of aromatic compounds and a large amount of coke formation, which can be a factor in reducing catalytic activity.

[0044] Comparative Example 5 Aromatic compounds were produced in the same manner as in Example 1, except that γ-alumina (manufactured by Sumitomo Chemical Co., Ltd., trade name KHD-24) was used instead of the catalyst obtained in Preparation Example 1. The results are shown in Table 2. The conversion rate was low, resulting in poor production efficiency of aromatic compounds and a large amount of coke generation, which can be a factor in reducing catalytic activity.

[0045] Comparative Example 6 The aromatic compound was produced in the same manner as in Example 7, except that aliphatic hydrocarbon compounds were not used and only heavy aromatic hydrocarbon compounds were used as raw materials. The results are shown in Table 2. A large amount of coke was produced, which can be a factor in the decrease of catalytic activity.

[0046] Comparative Example 7 Aromatic compounds were produced using the same method as in Example 7, except that heavy aromatic hydrocarbon compounds were not used and only aliphatic hydrocarbon compounds were used as raw materials. The results are shown in Table 2. The production efficiency of aromatic compounds, including benzene and toluene, was inferior.

[0047] [Table 1]

[0048] [Table 2] [Industrial applicability]

[0049] The present invention provides a method for producing aromatic compounds that exhibits excellent selectivity and efficiency in the simultaneous production of benzene and toluene even in a catalytic reaction using heavy aromatic hydrocarbon compounds as raw materials, and is therefore extremely useful industrially.

Claims

1. When producing aromatic compounds by contacting heavy aromatic hydrocarbon compounds belonging to aromatic hydrocarbon compounds with 8 to 15 carbon atoms and a boiling point range of 130 to 250°C with aliphatic hydrocarbon compounds with a catalyst containing a 10-membered ring and / or 12-membered ring pore zeolite, benzene and toluene are produced simultaneously. The 10-membered ring and / or 12-membered ring pore zeolite is a zeolite with a SiO₂ / Al₂O₃ molar ratio of 200 or less. The heavy aromatic hydrocarbons / aliphatic hydrocarbons (by weight) are supplied in a ratio of 90 / 10 to 10 / 90. A method for producing aromatic compounds, characterized by the absence of hydrogen addition.

2. The method for producing an aromatic compound according to claim 1, characterized in that the 10-membered ring and / or 12-membered ring pore zeolite is an MFI-type zeolite.

3. A method for producing an aromatic compound according to claim 1 or 2, characterized in that the heavy aromatic hydrocarbon compound is at least one selected from the group consisting of ethylbenzene, cumene, xylene, triisopropylbenzene, styrene, allylbenzene, and divinylbenzene.

4. A method for producing an aromatic compound according to claim 1 or 2, characterized in that the aliphatic hydrocarbon compound is at least one selected from the group consisting of butane, hexane, heptane, octane, nonane, butene, pentene, hexene, heptene, octane, nonene, cyclobutane, cyclopentane, methylcyclopentane, cyclohexane, and methylcyclohexane.

5. A method for producing an aromatic compound according to claim 1 or 2, characterized in that the reaction temperature is 300 to 600°C and the reaction pressure is 0.05 to 1 MPa.

6. Heavy aromatic hydrocarbon compounds and aliphatic hydrocarbon compounds are used in a ratio of 0.1h of raw material gas volume to catalyst volume. －１ ~50,000h －１ A method for producing an aromatic compound according to claim 1 or 2, characterized by supplying it at a spatial velocity.

7. A method for producing an aromatic compound according to claim 1 or 2, characterized in that the catalyst contains at least one metal selected from silver, calcium, magnesium, strontium, barium, gallium, and zinc.

8. A method for producing an aromatic compound according to claim 1 or 2, characterized in that the aliphatic hydrocarbon compound includes an aliphatic hydrocarbon compound derived from plants and / or from chemical recycling.

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