JP6733501B2 - Aromatic compound production catalyst and method for producing aromatic compound - Google Patents

Description

TECHNICAL FIELD The present invention relates to an aromatic compound production catalyst containing a specific MFI zeolite and a method for producing an aromatic compound using the same, and in particular to a production containing an MFI zeolite having a relatively uniform mesopore group. TECHNICAL FIELD The present invention relates to an aromatic compound production catalyst having excellent properties, stability, swing operation and long life, and an aromatic compound production method using the same.

Zeolites are used as adsorbents, molecular sieves, highly selective catalysts, etc. that utilize uniform pores derived from the zeolite structure. The zeolite is characterized by having pores called micropores having a pore diameter of 2 nm or less in the skeleton structure. In the case of a reaction in which a molecule having a molecular diameter smaller than 2 nm is used as a reaction substrate and zeolite is used as a catalyst, the reaction substrate diffuses into the micropores and the reaction proceeds inside the micropores.

In the reaction using a zeolite catalyst, shape selectivity is exerted by the molecular sieving ability of micropores. That is, molecules larger than the pore size of the micropores cannot diffuse into the micropores (substrate selectivity) and cannot form intermediates larger than the size of the internal space of the micropores (intermediate selectivity). ), it is not possible to produce a product with a size larger than the size of the internal space of the micropores or to diffuse outside the micropores (product selectivity). Therefore, controlling the pore size of the micropores is an important factor for selectively producing the desired product by using zeolite as a catalyst.

Examples of using zeolite as a catalyst include disproportionation of toluene (for example, refer to Patent Document 1) and isomerization of xylene (for example, refer to Patent Document 2).

The reactions described in these prior art documents mainly utilize the shape selectivity derived from the pore size of the micropores of the MFI-type zeolite. That is, the theoretical value of the entrance diameter of the micropores of the MFI-type zeolite is about 0.5 nm, and it is considered to be an effective reaction field for producing molecules having a molecular diameter close to this pore diameter. Similarly, the diffusivity of molecules in the micropores also largely depends on the size of the micropores, that is, the entrance diameter of the micropores and the size of the intersection of the micropore channels. .. Therefore, the diffusivity of the molecules in the micropores varies depending on the difference in the skeletal structure of the zeolite, which is an important factor in determining the reactivity.

Regarding the pore size of the micropores, for example, the theoretical value of the micropore inlet diameter of LTA-type zeolite is about 0.4 nm, and the theoretical value of the micropore inlet diameter of FAU-type zeolite is about 0.7 nm. It is largely determined by the framework structure of the zeolite.

Cation exchange is one of the means for improving the size of the micropores of zeolite. For example, the micropore inlet diameter of LTA-type zeolite is about 0.4 nm for sodium type, about 0.3 nm for potassium type, and about 0.5 nm for calcium type. The inlet diameter changes. This results in different shape selectivity of the molecule.

From the above, it is expected that by improving the size of the micropores of the zeolite, the shape selectivity of the zeolite catalyst and the diffusivity of the molecule are improved, and useful results can be obtained. For this reason, it would be beneficial to develop zeolites with improved micropore size.

Furthermore, research on MFI-type zeolite having mesopores (2 to 50 nm) larger than micropores (less than 2 nm) has been conducted (for example, see Non-Patent Document 1). Incidentally, conventionally, the formation of mesopores having a size of less than 10 nm has been mainly attempted, and there have been few reports concerning the formation of mesopores having a size of 10 nm or more. Several methods have been proposed for producing MFI-type zeolite having mesopores, for example, a method of eluting a silica component by alkali treatment to form mesopores (for example, see Non-Patent Document 2). .), a method of forming fine mesopores by mixing carbon fine particles at the time of crystallization of zeolite and removing the fine particles by firing (see, for example, Patent Document 3), and a method of forming mesopores by using a surfactant. Is also disclosed (see, for example, Patent Document 4), a method of forming regular mesopores using a surfactant is disclosed (see, for example, Patent Document 5), and fine crystals are formed. A method of assembling and forming mesopores between the assembled crystals (for example, see Non-Patent Document 1 and Patent Documents 6 to 8) and the like have been proposed.

Then, as an example of using a zeolite having mesopores as a catalyst, fluidized catalytic cracking (FCC) of reduced pressure gas oil using ultra-stable Y-type zeolite (USY) has been proposed (for example, Patent Document 9, See 10.).

In many cases, benzene, toluene, and xylene (hereinafter collectively referred to as aromatic compounds) are obtained by decomposing a feedstock oil (for example, naphtha) obtained by petroleum refining in a thermal decomposition reaction device. It is obtained by separating and purifying an aromatic compound from the obtained thermal decomposition product by distillation or extraction. In the production of aromatic compounds by these production methods, aliphatic and alicyclic hydrocarbons are included as thermal decomposition products other than aromatic compounds. Therefore, since the aliphatic and alicyclic hydrocarbons are simultaneously produced with the production of the aromatic compound, the production amount of the aromatic compound is adjusted according to the production amounts of the aliphatic and alicyclic hydrocarbons. Naturally, there was a limit to the production volume. Further, an aromatic compound can be produced by contacting an aliphatic or alicyclic hydrocarbon raw material with a catalyst mainly containing medium pore size zeolite at a temperature of about 400°C to about 800°C ( For example, see Non-Patent Documents 3 to 6.). Compared with the method for producing an aromatic compound by thermal decomposition, this production method has advantages that it has a low added value and that an aromatic compound can be produced from a surplus hydrocarbon raw material. Further, the catalysts used for producing these aromatic compounds are also being developed. For example, as a catalyst for producing an aromatic compound using a hydrocarbon containing paraffin, olefin, and naphthene as a raw material, a zinc-supported intermediate pore size zeolite-based catalyst in which the amount of scattered zinc is suppressed (see, for example, Patent Document 11), paraffin. As a catalyst used in the production of aromatic compounds using olefins, olefins, acetylene hydrocarbons, cyclic paraffins and cyclic olefins as raw materials, a catalyst in which platinum and a halogen component are simultaneously supported on L-type zeolite (for example, see Patent Document 12). ), the structure has a size of 0.1 to 100 mm, a crystalline porous aluminosilicate is present in the surface layer portion of the structure, and an inorganic support is present in the inner layer excluding the surface layer portion of the structure. Aromatization reaction catalyst characterized in that zinc and/or gallium are supported on the body (see, for example, Patent Document 13), and other catalysts for producing aromatic compounds using hydrocarbon as a raw material (for example, Patent Document) 14 to 15)) and the like have been proposed.

Japanese Patent No. 4014279 Japanese Patent No. 2598127 JP, 2008-19161, A JP, 2009-184888, A US Pat. No. 6,669,924 Japanese Patent Publication No. 61-21985 Japanese Patent No. 3417944 Japanese Patent No. 4707800 Japanese Patent No. 5339845 Japanese Patent 4773420 JP, 1998-33987, A Japanese Patent No. 3264447 Japanese Patent No. 5447468 Japanese Patent No. 3966429 Patent No. 5564769

Microporous and Mesoporous Materials Vol. 137, p. 92 (2011). Microporous and Mesoporous Materials Vol. 43, p. 83 (2001) Industrial & Engineering Chemistry Research Vol. 31, 995 (1992) Industrial & Engineering Chemistry Research Vol. 26, p. 647 (1987) Applied Catalysis Vol. 78, p. 15 (1991) Microporous and Mesoporous Materials Vol. 47, 253 (2001)

In the method for producing an aromatic compound using the catalytic reaction proposed in Patent Documents 11 to 15, from the viewpoint of production cost, the catalyst life (time from the activated state of the catalyst after the start of the reaction to the deactivation of the catalyst) Have challenges. Therefore, a method of selectively producing an aromatic compound from a hydrocarbon raw material having a relatively small molecule (particularly, having 10 or less carbon atoms) and stably for a long time is very significant.

The object of the present invention is to provide a novel fragrance which enables selective and stable production of aromatic compounds from a hydrocarbon raw material which is a relatively small molecule (especially having 10 or less carbon atoms) for a long time. Provided are a catalyst for producing a group compound and a method for producing an aromatic compound using the catalyst.

The present inventors have conducted extensive studies to solve the above problems, and as a result, an aromatic compound production catalyst containing a specific MFI-type zeolite selectively and stably produces an aromatic compound for a long time. The inventors have found that the catalyst can be used as a catalyst, and completed the present invention.

That is, the present invention includes an aromatic compound-producing catalyst characterized by containing an MFI-type zeolite satisfying the following characteristics (i) to (iv), and a group consisting of an olefin having 2 to 6 carbon atoms. The present invention relates to a method for producing an aromatic compound, which comprises contacting a lower olefin containing at least one of them to form an aromatic compound.
(I) The mesopore distribution curve has a peak, the full width at half maximum (hw) of the peak is hw≦20 nm, and the center value (μ) of the peak is 10 nm≦μ≦20 nm, which corresponds to the peak. The mesopore volume (pv) of the mesopores is 0.05 ml/g≦pv.
(Ii) It has no peak in the range of 0.1 to 3 degrees in powder X-ray diffraction measurement with a diffraction angle of 2θ.
(Iii) The average particle diameter (PD) is PD≦100 nm.
(Iv) a differential pore volume value in the range of 0.8nm from pore diameter _{0.3nm (dV P / d (d} P)) - distribution curve of micropores has a maximum value, the most differentiated fine in the range of pore diameter 0.4~0.5nm showing a large value of pore volume value _{(dV P / d (d P} )).

The present invention will be described in detail below.

The aromatic compound-producing catalyst of the present invention contains a specific MFI-type zeolite. By containing the specific MFI-type zeolite, the aromatic compound is selectively and stably produced for a long time. It becomes a catalyst that can be produced.

The MFI-type zeolite constituting the aromatic compound-producing catalyst of the present invention satisfies the characteristics (i) to (iv) described above, and as the MFI-type zeolite, a structure code MFI defined by the International Zeolite Association is used. 2 shows an aluminosilicate compound belonging to

The micropores in the present invention are micropores defined by IUPAC, which means pores having a pore diameter of 2 nm or less. Further, the mesopores are the mesopores defined by IUPAC, which means the pores having a pore diameter of 2 to 50 nm. The micropores and mesopores can be measured by a general nitrogen adsorption method at the liquid nitrogen temperature. Further, by analyzing the measurement results obtained by the nitrogen adsorption method, it is possible to obtain the values of the pore volume of the micropores and the mesopores, and the pore distribution curve. The following method can be used for the analysis, for example.

For micropores, the adsorption process is analyzed by the Saito-Folley method (AIChE Journal, 1991, Vol. 37, pages 429 to 436). For example, the value of the total pore volume of the micropores can be obtained by integrating the nitrogen gas desorption amount in the range where the pore diameter is 2 nm or less. Further, first, after obtaining a cumulative curve in which the vertical axis shows the nitrogen desorption amount V _P (mL/g) per unit mass and the horizontal axis shows the micropore diameter d _P (nm), the vertical axis shows the micropores. differential value of the micro pore diameter value of the nitrogen gas desorption amount from _{(dV P / d (d P} )) to differential pore volume value _{(dV P / d (d P} )) - distribution curve of micropores By setting the above, it is possible to obtain a peak corresponding to an increase in the nitrogen desorption amount per unit mass in the micropore diameter.

For mesopores, the desorption process is analyzed by the Barret-Joyner-Halenda method (Journal of the American Chemical Society, 1951, pp. 373-380). For example, the value of the total pore volume of the mesopores can be obtained by integrating the nitrogen gas desorption amount in the range where the pore diameter is 2 nm or more and 50 nm or less.

In addition, first, a vertical axis is a nitrogen desorption amount per unit mass V _P (mL/g), and a horizontal axis is a mesopore diameter D _P (nm). differential value in mesopore diameter value of the nitrogen gas desorption amount from when a _{(d (V P) / d} (D P)), the increase in peaks of nitrogen desorption amount per unit mass in the mesopore diameter Obtainable.

The MFI-type zeolite constituting the aromatic compound production catalyst of the present invention has a mesopore group having a substantially uniform pore diameter, and in the present invention, a mesopore group having a substantially uniform pore diameter. May be referred to as uniform mesopores. Then, specifically, the uniform mesopores are obtained by approximating the maximum peak among the peaks related to the mesopores in the pore distribution curve with a Gaussian function and standard deviation from the center value (μ) of the Gaussian function. Mesopores having a pore diameter in the range of 2 times (2σ) (μ±2σ). The pore volume of the uniform mesopores can be obtained by integrating the nitrogen gas desorption amount in the range of μ±2σ.

The MFI-type zeolite constituting the aromatic compound-producing catalyst of the present invention has (i) a mesopore distribution curve having a peak among MFI-type zeolites having a substantially uniform mesopore group. The half value width (hw) of the peak is hw≦20 nm, the center value (μ) of the peak is 10 nm≦μ≦20 nm, and the mesopore volume (pv) of the mesopores corresponding to the peak is pv≧0. It has a more uniform mesopore group of 05 ml/g.

The MFI-type zeolite constituting the aromatic compound-producing catalyst of the present invention has a peak in the pore distribution curve of mesopores, and the peak is almost uniform with small variations in pore diameter of hw≦20 nm or less. By having such a mesopore group, it becomes possible to construct an aromatic compound production catalyst having excellent reaction selectivity, and its effect becomes more remarkable when hw≦15 nm. The lower limit of hw is not particularly set, but it is preferably 1 nm or more because it constitutes an aromatic compound production catalyst having more excellent reaction selectivity. Further, when the center value (μ) when the peak is approximated by the Gaussian function is 10 nm≦μ≦20 nm, it becomes possible to selectively react even a molecule having a larger size. Further, pv≧0.05 ml/g constitutes a long-life catalyst for producing an aromatic compound, and 0.05 ml/g≦pv≦0.7 ml/g is preferable, and 0 is particularly preferable. 0.1 ml/g≦pv≦0.7 ml/g is preferable, and 0.2 ml/g≦pv≦0.5 ml/g is more preferable.

In addition, since the MFI-type zeolite constituting the aromatic compound-producing catalyst of the present invention enables a particularly selective reaction, the ratio of pv to the total pore volume shown in (i) above ( pvr) is preferably 30%≦pvr≦100%, more preferably 40%≦pvr≦100%.

The MFI-type zeolite constituting the aromatic compound-producing catalyst of the present invention does not have a peak in the range of 0.1 to 3 degrees in (ii) powder X-ray diffraction measurement with a diffraction angle of 2θ. This means that there is no regularity in the arrangement of mesopores and that there is no partition wall between mesopores, and when used as a catalyst, mass transfer between mesopores is easy. Therefore, the reaction efficiency is excellent.

The MFI-type zeolite constituting the aromatic compound-producing catalyst of the present invention is (iii) PD≦100 nm, and since it is also particularly excellent in heat resistance, 3 nm≦PD is preferable, and further 5 nm It is preferable that ≦PD. Here, in the case of zeolite with PD>100 nm, a substantially uniform mesopore group is not formed and the catalyst has reaction selectivity. The PD can be calculated and calculated from the external surface area using the following formula (1).
PD=6/S (1/2.29×10 ⁶ +0.18×10 ⁻⁶ ) (1)
(Here, S represents an outer surface area (m ² /g).)
The external surface area (S(m ² /g)) in the formula (1) can be obtained from the t-plot method using a general nitrogen adsorption method at a liquid nitrogen temperature. For example, when t is the thickness of the adsorption amount, a measurement point in the range of 0.6 to 1 nm for t is linearly approximated, and the external surface area is obtained from the slope of the obtained regression line.

As another method for measuring the particle size of MFI-type zeolite, for example, 10 or more arbitrary particles are selected from a photograph of a scanning electron microscope (SEM) or a transmission electron microscope (TEM), and the surface area average diameter thereof is selected. Can be mentioned.

MFI-type zeolite that constitutes the aromatic compound production catalyst of the present invention, (iv) a differential pore volume value in the range of 0.8nm from pore diameter _{0.3nm (dV P / d (d} P)) - micropores is has a maximum value, in which the range of pore diameter 0.4~0.5nm indicating the largest value of the differential pore volume value _{(dV P / d (d P} )) of the distribution curve .. When the pore size is in the range of 0.4 to 0.5 nm, the aromatic compound production catalyst exhibits high activity.

The MFI-type zeolite constituting the aromatic compound-producing catalyst of the present invention is not limited in its SiO ₂ /Al ₂ O ₃ (molar ratio), and among them, a catalyst excellent in heat resistance, reaction selectivity, and productivity. Therefore, the SiO ₂ /Al ₂ O ₃ (molar ratio) is preferably 20 or more and 200 or less. In addition, it is preferable that the pores do not contain a structure directing agent such as a tetrapropylammonium salt because the catalyst has excellent reaction selectivity and productivity.

As a method for producing the MFI-type zeolite constituting the aromatic compound production catalyst of the present invention, for example, aluminum in the skeleton of the MFI-type zeolite, which is a raw material satisfying the characteristics (i) to (iii) above, is removed by steam or the like. It can be manufactured by converting to aluminum. The temperature of the steam treatment at that time is preferably, for example, 400 to 900°C, particularly preferably 450 to 800°C, and further preferably 500 to 700°C. The partial pressure of steam is preferably 0.001 to 5 MPa, more preferably 0.01 to 0.5 MPa, and further preferably 0.05 to 0.2 MPa. The steam concentration is preferably, for example, 0.01 to 100 vol% steam/diluting gas. As the diluent gas, an inert gas such as nitrogen, air, oxygen, carbon monoxide, carbon dioxide, a mixed gas thereof, or the like can be used. The steam processing time can be arbitrarily selected.

Further, as a method for producing the MFI-type zeolite, which is a raw material satisfying the characteristics (i) to (iii), the following method can be exemplified.

Tetrapropylammonium (hereinafter sometimes referred to as “TPA”) Amorphous aluminosilicate gel is added to an aqueous solution of hydroxide and sodium hydroxide to suspend, and MFI-type zeolite is added to the resulting suspension. An MFI-type zeolite can be obtained by adding a seed crystal to obtain a raw material composition, crystallizing the obtained raw material composition, and firing it.

The form of using the MFI-type zeolite as the aromatic compound-producing catalyst of the present invention is not limited, and for example, the synthesized MFI-type zeolite powder is directly used as the catalyst, and compression molding is performed to obtain a specific shape. It can be used in any form such as using as a material, or by mixing with a binder or the like and molding to use as a specific shape.

By containing the MFI-type zeolite, the aromatic compound production catalyst of the present invention becomes an aromatic compound production catalyst excellent in efficiency such as reaction selectivity and productivity, and has, for example, 2 to 6 carbon atoms. It is possible to efficiently produce an aromatic compound by contacting with a hydrocarbon. As the hydrocarbon having 2 to 6 carbon atoms, any hydrocarbon can be used as long as it belongs to the category, and examples thereof include saturated hydrocarbons, unsaturated hydrocarbons, alicyclic hydrocarbons, and mixtures thereof. More specifically, ethane, ethylene, propane, propylene, cyclopropane, n-butane, isobutane, 1-butene, 2-butene, isobutene, butadiene, cyclobutene, cyclobutane, n-pentane, 1- Pentane, 2-pentane, 1-pentene, 2-pentene, 3-pentene, n-hexane, 1-hexane, 2-hexane, 1-hexene, 2-hexene, 3-hexene, hexadiene, cyclohexane and mixtures thereof. Can be mentioned.

And, the aromatic compound production catalyst of the present invention becomes an aromatic compound production catalyst excellent in efficiency such as reaction selectivity and productivity by including the MFI-type zeolite. By contacting with at least one lower olefin selected from the group consisting of 6 olefins, it is possible to efficiently produce an aromatic compound. Examples of the olefin at that time include ethylene, propylene, 1-butene, 2-butene, isobutene, 1-pentene, 2-pentene, 3-pentene, 1-hexene, 2-hexene, 3-hexene, and mixtures thereof. Can be mentioned.

Further, by bringing a hydrocarbon mixture having 4 carbon atoms into contact with a catalyst containing the MFI-type zeolite, a method for producing an aromatic compound having excellent efficiency such as reaction selectivity and productivity is obtained. Examples of the hydrocarbon mixture of the number 4 include those referred to as C4 fractions among the cracked fractions of petroleum such as naphtha, and more specifically, n-butane, isobutane, 1 -Butene, 2-butene, isobutene, butadiene, cyclobutene, a mixture of cyclobutane and the like can be mentioned.

By contacting a hydrocarbon mixture having 6 carbon atoms with a catalyst containing the MFI-type zeolite, a method for producing an aromatic compound having excellent efficiency such as reaction selectivity and productivity is obtained. As the hydrocarbon mixture, there may be mentioned, for example, those which are referred to as C6 fraction among the cracked fractions of petroleum such as naphtha, and more specifically. Examples thereof include a mixture of n-hexane, 1-hexene, 2-hexene, hexadiene, cyclohexane and the like.

Further, the aromatic compound-producing catalyst of the present invention is a conversion catalyst having excellent efficiency such as reaction selectivity and productivity by including the MFI-type zeolite, and for example, saturated catalyst having 2 to 6 carbon atoms. By contacting with an aliphatic hydrocarbon or an alicyclic hydrocarbon, an aromatic compound can be efficiently produced. Examples of the saturated aliphatic hydrocarbon or alicyclic hydrocarbon at that time include ethane, propane, butane, isobutane, pentane, hexane, cyclopropane, cyclobutane, cyclohexane, and a mixture thereof.

Then, in the reaction which is the embodiment in that case, the reaction temperature is not particularly limited as long as it is possible to produce an aromatic compound, and among them, the production of an olefin or an alkane is suppressed, and the heat resistance is higher than necessary. The range of 400 to 800° C. is desirable because the reaction of an aromatic compound does not require a reactor. The reaction pressure is also not limited, and the operation can be performed in a pressure range of, for example, 0.05 MPa to 5 MPa. Then, the olefin and the reaction raw material to the aromatic compound production catalyst of the present invention, the hydrocarbon feed is not intended to catalyst volume is particularly limited as the ratio of the volume of raw material gas, for example 1h ^-1 ~50000h ^-1 The space velocity of the degree can be mentioned. When supplying an olefin or a hydrocarbon as a raw material gas, a single gas of the olefin and the hydrocarbon, a mixed gas, and a single gas selected from an inert gas such as nitrogen, hydrogen, carbon monoxide, and carbon dioxide. Alternatively, it may be used as diluted with a mixed gas.

There is no limitation on the reaction form, and for example, not only fixed bed, transport bed, fluidized bed, moving bed, multitubular reactor but also continuous flow type, intermittent flow type, swing type reactor and the like can be used. And, since it is a particularly efficient method for producing an aromatic compound, the reaction system using a swing reactor is preferable. The aromatic compound production catalyst of the present invention is preferably a catalyst for swing operation because it is excellent in aromatic compound production efficiency, long catalyst life and excellent regeneration resistance. Specifically, there is a plurality of reaction fields having the aromatic compound-producing catalyst of the present invention as a catalyst for swing operation, and swing operation is performed in which at least one reaction field regenerates the aromatic compound-producing catalyst. ..

Further, the aromatic compound produced is not particularly limited as long as it belongs to the category called an aromatic compound, for example, benzene, toluene, xylene, trimethylbenzene, ethylbenzene, propylbenzene, butylbenzene, naphthalene, Examples thereof include methylnaphthalene, and benzene, toluene, and xylene are particularly preferable.

The present invention relates to an aromatic compound production catalyst containing a specific MFI-type zeolite, and particularly to a catalyst having a long catalyst when producing an aromatic compound from an olefin, a saturated aliphatic hydrocarbon or an alicyclic hydrocarbon. The present invention provides a catalyst for producing an aromatic compound which can obtain a long life and is suitable for swing operation, and a method for producing an aromatic compound using the catalyst, which is very useful industrially.

The present invention will be specifically described below with reference to examples.
The MFI zeolite and the aromatic compound production catalyst used in the examples were measured and defined by the following methods.

-Measurement of pore distribution, pore diameter, and external surface area-
The pore distribution and pore diameter of zeolite were measured by nitrogen adsorption measurement.

For the nitrogen adsorption measurement, a general nitrogen adsorption device ((trade name) BELSOAP-max, manufactured by Bell Japan Ltd.) was used, and the relative pressure (P/P ₀ ) was measured at 0.025 intervals on the adsorption side. The desorption side was measured at a relative pressure of 0.05 intervals. The outer surface area was determined by t-plot method by linearly approximating the range of the thickness (t=0.6 to 1.0 nm) of the adsorption layer. BELMaster (Ver. 2.3.1) manufactured by Bell Japan Ltd. was used for the analysis of the pore distribution curve.

The adsorption process of nitrogen adsorption measurement was analyzed by the Saito-Folley method (AIChE Journal, 1991, 37, p. 429 to 436), and the horizontal axis represents the pore microdiameter constant and the vertical axis represents the desorption amount of nitrogen gas. The value of the micropore distribution curve of micropores was obtained.

Then, the desorption process of nitrogen adsorption measurement is analyzed by the Barret-Joyner-Halenda method (Journal of the American Chemical Society, 1951, pages 373 to 380). A pore distribution curve of mesopores, which is the differential value of the desorption amount of, was obtained. The total pore volume of the mesopores was obtained by integrating the nitrogen gas desorption amount in the range of 2 nm or more and 50 nm or less.

Then, of the peaks of the differential value (d(V/m)/d(D)) of the desorption amount of nitrogen gas from the mesopores in the mesopore diameter value, the maximum peak is analyzed by the intensity approximation of the Gaussian function. Then, the mesopores having a diameter within the range (=μ±2σ) of twice the standard deviation (2σ) from the center value (μ) of the Gaussian function were defined as uniform mesopores. The pore volume of the uniform mesopores was obtained by integrating the nitrogen gas desorption amount in the range of ±2σ with reference to the central value (μ).

~Measurement of average particle size~
The average particle size was calculated from the outer surface area using the above formula (1). Wherein (1), S is the outer surface area ^(m 2 / g), PD is the average particle diameter (m). The outer surface area (S(m ² /g)) in the formula (1) was obtained from the t-plot method by the nitrogen adsorption method at the liquid nitrogen temperature.

~SiO ₂ / _{Al 2 O 3} molar measurements ratio ~
The SiO ₂ /Al ₂ O ₃ molar ratio of the zeolite is such that MFI-type zeolite is dissolved in a mixed aqueous solution of hydrofluoric acid and nitric acid, and this is melted by a general ICP device ((trade name) OPTIMA3300DV, manufactured by PerkinElmer). It was measured and determined by optical emission spectroscopy (ICP-AES).

-Measurement of aggregate diameter-
As the aggregation diameter, the volume average diameter (D ₅₀ ) of the aggregation particle diameters was measured by the dynamic scattering method. For the measurement, (trade name) Microtrac HRA (Model 9320-x100) (manufactured by Nikkiso Co., Ltd.) was used. In the measurement, the particle refractive index was 1.66, the particles were set to transparent non-spherical particles, and the solvent liquid refractive index was 1.33.

-Measurement of powder X-ray diffraction-
The measurement was performed in the atmosphere using an X-ray diffractometer (manufactured by Spectris, (trade name) X'pert PRO MPD) with a tube voltage of 45 kV and a tube current of 40 mA and CuKα1. The range of 0.04 to 5 degrees was analyzed at 0.08 degrees/step and 200 seconds/step. Also, the background corrected by the absorption rate of the direct beam is removed.

The presence/absence of a peak can be visually confirmed, or a peak search program may be used. A general program can be used as the peak search program. For example, when the horizontal axis is 2θ (degrees) and the vertical axis is intensity (au), the measurement results are smoothed by the SAVITSKY & GOLAY formula and the Sliding Polynomial filter, and then second-order differentiation is performed. If there is a negative value, it is judged that the peak exists.

-Aromatic compound manufacturing apparatus and manufacturing method thereof-
With respect to the aromatic compound-producing catalysts obtained in the examples, an aromatic compound was produced by the following method, and its evaluation was performed.

A swing reactor was used in which two fixed bed gas phase flow reactors using stainless steel reaction tubes (inner diameter 16 mm, length 600 mm) were connected in parallel. After filling the middle stage of each of the two stainless steel reaction tubes with an aromatic compound production catalyst and performing heat pretreatment under a flow of dry air, the two reactors were switched at predetermined intervals. The operation was performed and the raw material gas was alternately fed. While the raw material gas was supplied and reacted in one reactor (reaction side), air gas was circulated in the other reactor (regeneration side) to regenerate the aromatic compound-producing catalyst by coke combustion. The device conditions and operating conditions of the swing reactor are not limited to the conditions described in this example, and can be selected as appropriate. Then, for heating, a ceramic tubular furnace was used to control the temperature of the catalyst layer. The reaction outlet gas and the reaction liquid were collected, and the gas component and the liquid component were individually analyzed using a gas chromatograph. The gas component was analyzed using a gas chromatograph (manufactured by Shimadzu Corporation, (trade name) GC-1700) equipped with a TCD detector. As the filler, PorapakQ (trade name) manufactured by Waters or MS-5A (trade name) manufactured by GL Sciences was used. The liquid component was analyzed using a gas chromatograph (manufactured by Shimadzu Corporation, (trade name) GC-2015) equipped with an FID detector. As the separation column, a capillary column (GL-1 (trade name) TC-1) was used.

The reaction conditions were set as follows.

(Aromatic compound production conditions)
Catalyst temperature: 600°C.
Circulating gas: mixed gas of 50 mol% of source gas+50 mol% of nitrogen, 100 ml/min.
Ratio of volume of raw material gas to catalyst volume: 1000/hour.
Catalyst weight: 1.5 g.
Catalyst shape: MFI-type zeolite powder was molded at 400 kgf/cm ² for 1 minute and then pulverized to give a pellet shape of about 1 mm.
Reaction pressure: 0.1 MPa.

(Catalyst regeneration condition and air purge condition during swing operation)
Catalyst temperature: 600°C.
Circulating gas: air 50 ml/min.
Ratio of air gas volume to catalyst volume: 1000/hour.
Pressure: 0.1 MPa.

(Nitrogen purging conditions)
Catalyst temperature: 600°C.
Circulating gas: nitrogen 50 ml/min.
Ratio of volume of nitrogen gas to catalyst volume: 1000/hour.
Pressure: 0.1 MPa.

The MFI-type zeolite was produced with reference to JP 2013-227203 A.

Example 1
Aluminum hydroxide was dissolved in an aqueous solution of TPA bromide and sodium hydroxide. After tetraethoxysilane was added to the obtained aqueous solution, MFI-type zeolite was added as a seed crystal to the aqueous solution to form a raw material composition, and ethanol generated was removed by evaporation. The composition of the raw material composition in that case is as follows.
SiO ₂ /Al ₂ O ₃ molar ratio=28, TPA/Si molar ratio=0.05, Na/Si molar ratio=0.17, OH/Si molar ratio=0.17, H ₂ O/Si molar ratio= 10
Then, the obtained raw material composition was sealed in a stainless steel autoclave and crystallized for 4 days with stirring at 115° C. to obtain a slurry-like mixed liquid. The crystallized slurry mixture was subjected to solid-liquid separation with a centrifugal sedimentation machine, solid particles were washed with a sufficient amount of pure water, and dried at 110°C to obtain a dry powder. 10 g of the obtained dry powder was calcined at 550° C. for 1 hour, then exchanged, filtered and washed in 100 ml of a 20% by weight ammonium chloride aqueous solution at 60° C. for 20 hours to obtain an ammonium-type MFI zeolite. Then, ammonium-type MFI-type zeolite was calcined at 550° C. for 1 hour to obtain a zeolite having an MFI-type skeleton structure. This MFI-type zeolite had an average particle diameter of 26 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 26, and a total pore volume of mesopores of 0.43 ml/g. The micropore distribution curve had a maximum value having the largest differential pore volume value at a pore diameter of 0.3875 nm. The half-value width of the peak of the uniform mesopores in the mesopore distribution curve was 15 nm, and the center value was 17 nm. The pore volume of the uniform mesopores was 0.39 ml/g, and the ratio of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 91%.

Steam treatment was applied to the obtained MFI-type zeolite. In the steam treatment, 30 vol% steam/air was supplied to the MFI zeolite kept at 600° C. in a fixed bed for 10 minutes. After steam treatment, it was naturally cooled to obtain MFI-type zeolite.

The obtained MFI-type zeolite had an average particle diameter of 26 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 26, and a total pore volume of mesopores of 0.43 ml/g. The micropore distribution curve had a maximum value having the largest differential pore volume value at a pore diameter of 0.4125 nm. The half-value width of the peak of the uniform mesopores in the mesopore distribution curve was 15 nm, and the center value was 17 nm. The pore volume of the uniform mesopores was 0.39 ml/g, and the ratio of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 91%. In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. FIG. 1 shows the micropore distribution curve of the obtained MFI zeolite.

Using the obtained MFI-type zeolite as an aromatic compound production catalyst and ethylene as a raw material, an aromatic compound was produced under the above conditions. The respective conditions on the reaction side and the regeneration side of the swing reactor at that time are as follows.

(Reaction side)
The raw material gas was circulated for 900 minutes into the reaction tube heated at 600° C., and then the raw material gas feed was immediately switched to the direction of the reaction tube on the regeneration side.

(Playback side)
At the same time when the raw material gas feed to the reaction tube on the reaction side is started, nitrogen purge (1) is started on the reaction tube on the regeneration side heated at 600° C., and nitrogen purge is carried out for 30 minutes to make the inside of the reaction tube sufficiently nitrogen atmosphere. Replaced. Then, the supply gas was immediately changed from nitrogen to air, and air purging was performed for 10 minutes to sufficiently replace the inside of the reaction tube with an air atmosphere. Then, air was circulated for 120 minutes to regenerate the aromatic compound-producing catalyst. Then, the supply gas was immediately changed from air to nitrogen, and a nitrogen purge (2) was performed for 10 minutes to sufficiently replace the inside of the reaction tube with a nitrogen atmosphere. Subsequently, nitrogen purge (3) was performed for 730 minutes to sufficiently replace the inside of the reaction tube with a nitrogen atmosphere. Next, the nitrogen gas feed line was immediately switched to the reaction tube on the reaction side, and at the same time, the raw material gas feed to the reaction tube on the regeneration side was started. After that, a series of treatments similar to the above was repeated to continuously obtain a product feed. In addition, in the reactions described in the following Examples and Comparative Examples, operation was performed in the same procedure, and only the raw material gas flow time and the nitrogen purge (3) time were changed. Table 1 shows the gas circulation time in each step.

Table 2 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to obtain a stable product feed without significant decrease in conversion, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 8995 minutes.

Example 2
Using the MFI-type zeolite obtained in Example 1 as an aromatic compound production catalyst and propylene as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 3 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly reducing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 15095 minutes.

Comparative Example 1
MFI-type zeolite was obtained in the same manner as in Example 1 except that the steam treatment was not performed.

The obtained MFI zeolite had an average particle size of 26 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 26, and a total mesopore volume of 0.43 ml/g. The micropore distribution curve had a maximum value having the largest differential pore volume value at a pore diameter of 0.3875 nm. The half-value width of the peak of the uniform mesopores in the mesopore distribution curve was 15 nm, and the center value was 17 nm. The pore volume of the uniform mesopores was 0.39 ml/g, and the ratio of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 91%. In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. FIG. 1 shows the micropore distribution curve of the obtained MFI zeolite.

Using the obtained MFI-type zeolite as an aromatic compound production catalyst and ethylene as a raw material, a conversion reaction to an aromatic compound was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 4 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 8995 minutes, and it was difficult to say that the production was stable.

Comparative example 2
Using the MFI-type zeolite obtained in Comparative Example 1 as an aromatic compound production catalyst and propylene as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 5 shows the raw material gas flow time, conversion rate, and each product yield. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain value range until the raw material gas flow time of 15095 minutes, and it was difficult to say stable production.

Example 3
An amorphous aluminosilicate gel was added to and suspended in an aqueous solution of TPA hydroxide and sodium hydroxide. MFI-type zeolite was added to the obtained suspension as seed crystals to obtain a raw material composition. The amount of seed crystals added was 0.7% by weight based on the weight of Al ₂ O ₃ and SiO _{2 in} the raw material composition. Further, ethanol generated in the raw material composition was removed by evaporation.

The composition of the above raw material composition is as follows.
SiO ₂ /Al ₂ O ₃ molar ratio=44, TPA/Si molar ratio=0.05, Na/Si molar ratio=0.16, OH/Si molar ratio=0.21, H ₂ O/Si molar ratio= 10
The obtained raw material composition was sealed in a stainless steel autoclave and crystallized for 4 days while stirring at 115° C. to obtain a slurry-like mixed liquid. The crystallized slurry mixture was subjected to solid-liquid separation with a centrifugal sedimentation machine, solid particles were washed with a sufficient amount of pure water, and dried at 110°C to obtain a dry powder. Then, 10 g of the obtained dry powder was calcined at 550° C. for 1 hour, and then exchanged, filtered and washed in 100 ml of a 20 wt% ammonium chloride aqueous solution at 60° C. for 20 hours to obtain an ammonium-type MFI zeolite. Then, ammonium-type MFI-type zeolite was calcined at 550° C. for 1 hour to obtain MFI-type zeolite. The obtained MFI-type zeolite had an average particle diameter of 27 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 40, and an aggregate diameter of 46 μm, and the total pore volume of mesopores was 0.40 ml/g. Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.3875 nm. Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of MFI-type zeolite was 9 nm, and the center value was 16 nm. The pore volume of the uniform mesopores was 0.31 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 77%.

Steam treatment was applied to the obtained MFI-type zeolite. In the steam treatment, 30 vol% steam/air was supplied to the zeolite kept at 600° C. in a fixed bed for 10 minutes. After steam treatment, it was naturally cooled to obtain MFI-type zeolite.

The micropore distribution curve of the obtained MFI-type zeolite has an average particle diameter of 27 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 40, and an aggregate diameter of 46 μm, and the total mesopore volume is 0.40 ml/g. Met. Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.4125 nm. Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of MFI-type zeolite was 9 nm, and the center value was 16 nm. The pore volume of the uniform mesopores was 0.31 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 77%. In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. FIG. 1 shows the micropore distribution curve of the obtained MFI zeolite.

Using the obtained MFI-type zeolite as an aromatic compound production catalyst and ethylene as a raw material, a conversion reaction to an aromatic compound was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 6 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to obtain a stable product feed without significant decrease in conversion, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 8995 minutes.

Example 4
Using the MFI-type zeolite obtained in Example 3 as a catalyst for producing an aromatic compound and using propylene as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 7 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly reducing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 15095 minutes.

Comparative Example 3
MFI-type zeolite was obtained in the same manner as in Example 3 except that the steam treatment was not performed.

The obtained MFI-type zeolite had an average particle diameter of 27 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 40, and an aggregate diameter of 46 μm, and the total pore volume of mesopores was 0.40 ml/g. Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.3875 nm. Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of MFI-type zeolite was 9 nm, and the center value was 16 nm. The pore volume of the uniform mesopores was 0.31 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 77%. In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. FIG. 1 shows the micropore distribution curve of the obtained MFI zeolite.

Using the obtained MFI zeolite as a catalyst, ethylene was used as a raw material, and a conversion reaction was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 8 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 8995 minutes, and it was difficult to say that the production was stable.

Comparative Example 4
Using the MFI-type zeolite obtained in Comparative Example 3 as an aromatic compound production catalyst and propylene as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 9 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain value range until the raw material gas flow time of 15095 minutes, and it was difficult to say stable production.

Example 5
Aluminum hydroxide was dissolved in an aqueous solution of TPA hydroxide and sodium hydroxide. Tetraethoxysilane was mixed and suspended in the obtained aqueous solution. MFI-type zeolite was added to the obtained suspension as a seed crystal to prepare a raw material composition. The amount of seed crystals added was 0.7% by weight based on the weight of Al ₂ O ₃ and SiO _{2 in} the raw material composition. The type of seed crystal and the amount added are the same as in Example 1. The ethanol generated in the raw material composition was removed by evaporation.
The composition of the above raw material composition is as follows.
SiO ₂ /Al ₂ O ₃ molar ratio=44, TPA/Si molar ratio=0.07, Na/Si molar ratio=0.14, OH/Si molar ratio=0.21, H ₂ O/Si molar ratio= 10
The obtained raw material composition was sealed in a stainless steel autoclave and crystallized for 4 days while stirring at 115° C. to obtain a slurry-like mixed liquid. The crystallized slurry mixture was subjected to solid-liquid separation with a centrifugal sedimentation machine, solid particles were washed with a sufficient amount of pure water, and dried at 110°C to obtain a dry powder.

10 g of the obtained dry powder was calcined at 550° C. for 1 hour, then exchanged, filtered and washed in 100 ml of a 20% by weight ammonium chloride aqueous solution at 60° C. for 20 hours to obtain an ammonium-type MFI zeolite. Then, ammonium-type MFI-type zeolite was calcined at 550° C. for 1 hour to obtain MFI-type zeolite.

The average particle size of the obtained MFI zeolite was 43 nm, and the SiO ₂ /Al ₂ O ₃ molar ratio was 39. The total pore volume of mesopores of the obtained MFI zeolite was 0.19 ml/g. Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.3875 nm.

Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of the obtained MFI-type zeolite was 5 nm, and the center value was 11 nm. The pore volume of the uniform mesopores was 0.08 ml/g. Further, the ratio of the pore volume of the uniform mesopores to the total pore volume of the mesopores in the MFI zeolite was 44%.

Steam treatment was applied to the obtained MFI-type zeolite. In the steam treatment, 30 vol% steam/air was supplied to the zeolite kept at 600° C. in a fixed bed for 10 minutes. After steam treatment, it was naturally cooled to obtain MFI-type zeolite.

The average particle size of the obtained MFI zeolite was 43 nm, and the SiO ₂ /Al ₂ O ₃ molar ratio was 39. The total pore volume of mesopores of the obtained MFI zeolite was 0.19 ml/g.
Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.4125 nm. Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of MFI-type zeolite was 5 nm, and the center value was 11 nm. The pore volume of the uniform mesopores was 0.08 ml/g. Further, the ratio of the pore volume of the uniform mesopores to the total pore volume of the mesopores in the MFI zeolite was 44%.

In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. FIG. 2 shows a micropore distribution curve of the obtained MFI zeolite.

Using the obtained MFI-type zeolite as an aromatic compound production catalyst and ethylene as a raw material, a conversion reaction to an aromatic compound was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 10 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to obtain a stable product feed without significant decrease in conversion, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 8995 minutes.

Example 6
Using the MFI-type zeolite obtained in Example 5 as a catalyst for producing an aromatic compound and using propylene as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 11 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly reducing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 15095 minutes.

Comparative Example 5
MFI-type zeolite was obtained in the same manner as in Example 5 except that the steam treatment was not performed.

The average particle size of the obtained MFI zeolite was 43 nm, and the SiO ₂ /Al ₂ O ₃ molar ratio was 39. The total pore volume of mesopores of the obtained MFI zeolite was 0.19 ml/g.
Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.3875 nm.

Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of the obtained MFI-type zeolite was 5 nm, and the center value was 11 nm. The pore volume of the uniform mesopores was 0.08 ml/g. Further, the ratio of the pore volume of the uniform mesopores to the total pore volume of the mesopores in the MFI zeolite was 44%.

In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. FIG. 2 shows a micropore distribution curve of the obtained MFI zeolite.

Using the obtained MFI zeolite as a catalyst, ethylene was used as a raw material, and a conversion reaction was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 12 shows the raw material gas flow time, conversion rate, and each product yield. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 8995 minutes, and it was difficult to say that the production was stable.

Comparative Example 6
Using the MFI-type zeolite obtained in Comparative Example 5 as an aromatic compound production catalyst, and using propylene as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 13 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain value range until the raw material gas flow time of 15095 minutes, and it was difficult to say stable production.

Comparative Example 7
Aluminum hydroxide was dissolved in an aqueous solution of TPA hydroxide and sodium hydroxide. Tetraethoxysilane was added to and suspended in the obtained aqueous solution. MFI-type zeolite was added to the obtained suspension as seed crystals to obtain a raw material composition. The generated ethanol was removed by evaporation.

The composition of the above raw material composition is as follows.
SiO ₂ / _Al 2 _{O 3} molar ratio = 59, TPA / Si molar ratio = 0.20, Na / Si molar ratio = 0.06, OH / Si molar ratio = _0.26, H 2 O / Si molar ratio = 10
This raw material composition was reacted and treated in the same manner as in Example 1 to obtain an MFI type zeolite. The average particle diameter of the obtained MFI zeolite was 42 nm, and the SiO ₂ /Al ₂ O ₃ molar ratio was 49. The total pore volume of mesopores present in the obtained MFI-type zeolite was 0.20 ml/g.
Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.3875 nm.

The half-width of the peak of the uniform mesopores in the pore distribution curve of the obtained MFI-type zeolite was 3 nm, and the center value was 6 nm. The pore volume of the uniform mesopores was 0.04 ml/g, and the proportion of the pore volume of the uniform mesopores in the total pore volume of the mesopores was 23%.

Steam treatment was applied to the obtained MFI-type zeolite. In the steam treatment, 30 vol% steam/air was supplied to the zeolite kept at 600° C. in a fixed bed for 10 minutes. After steam treatment, it was naturally cooled to obtain MFI-type zeolite.

The average particle diameter of the obtained MFI zeolite was 42 nm, and the SiO ₂ /Al ₂ O ₃ molar ratio was 49. The total pore volume of mesopores present in the obtained MFI-type zeolite was 0.20 ml/g.
Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.4125 nm.

The half-width of the peak of the uniform mesopores in the pore distribution curve of the obtained MFI-type zeolite was 3 nm, and the center value was 6 nm. The pore volume of the uniform mesopores was 0.04 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 23%.

In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. FIG. 2 shows a micropore distribution curve of the obtained MFI zeolite.

Using the obtained MFI-type zeolite as an aromatic compound production catalyst and ethylene as a raw material, a conversion reaction to an aromatic compound was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 14 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 8995 minutes, and it was difficult to say that the production was stable.

Comparative Example 8
Using the MFI-type zeolite obtained in Comparative Example 7 as an aromatic compound production catalyst, and using propylene as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 15 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain value range until the raw material gas flow time of 15095 minutes, and it was difficult to say stable production.

Example 7
Aluminum hydroxide was dissolved in an aqueous solution of TPA bromide and sodium hydroxide. After tetraethoxysilane was added to the obtained aqueous solution, MFI-type zeolite was added as a seed crystal to the aqueous solution to form a raw material composition, and ethanol generated was removed by evaporation. The composition of the raw material composition in that case is as follows.
SiO ₂ /Al ₂ O ₃ molar ratio=28, TPA/Si molar ratio=0.05, Na/Si molar ratio=0.17, OH/Si molar ratio=0.17, H ₂ O/Si molar ratio= 10
Then, the obtained raw material composition was sealed in a stainless steel autoclave and crystallized for 4 days with stirring at 115° C. to obtain a slurry-like mixed liquid. The crystallized slurry mixture was subjected to solid-liquid separation with a centrifugal sedimentation machine, solid particles were washed with a sufficient amount of pure water, and dried at 110°C to obtain a dry powder. 10 g of the obtained dry powder was calcined at 550° C. for 1 hour, then exchanged, filtered and washed in 100 ml of a 20% by weight ammonium chloride aqueous solution at 60° C. for 20 hours to obtain an ammonium-type MFI zeolite. Then, ammonium-type MFI-type zeolite was calcined at 550° C. for 1 hour to obtain a zeolite having an MFI-type skeleton structure. This MFI-type zeolite had an average particle diameter of 26 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 26, and a total pore volume of mesopores of 0.42 ml/g. The micropore distribution curve had a maximum value having the largest differential pore volume value at a pore diameter of 0.3875 nm. The half-value width of the peak of the uniform mesopores in the mesopore distribution curve was 15 nm, and the center value was 17 nm. The pore volume of the uniform mesopores was 0.39 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 93%.

Steam treatment was applied to the obtained MFI-type zeolite. In the steam treatment, 30 vol% steam/air was supplied to the MFI zeolite kept at 600° C. in a fixed bed for 10 minutes. After steam treatment, it was naturally cooled to obtain MFI-type zeolite.

The obtained MFI-type zeolite had an average particle diameter of 26 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 26, and a total pore volume of mesopores of 0.42 ml/g. The micropore distribution curve had a maximum value having the largest differential pore volume value at a pore diameter of 0.4125 nm. The half-value width of the peak of the uniform mesopores in the mesopore distribution curve was 15 nm, and the center value was 17 nm. The pore volume of the uniform mesopores was 0.39 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 93%. In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. The micropore distribution curve of the obtained MFI zeolite is shown in FIG.

An aromatic compound was produced under the same conditions as in Example 1, using the obtained MFI-type zeolite as a catalyst for conversion to an aromatic compound and using n-butane as a raw material.
Table 1 shows the gas circulation time in each step.

Table 16 shows the raw material gas circulation time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 44995 minutes.

Example 8
Using the MFI-type zeolite obtained in Example 7 as a catalyst for conversion to an aromatic compound and using n-hexane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 17 shows the raw material gas flow time, conversion rate, and each product yield. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 45995 minutes.

Comparative Example 9
MFI-type zeolite was obtained in the same manner as in Example 7 except that the steam treatment was not performed.

The obtained MFI-type zeolite had an average particle diameter of 26 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 26, and a total mesopore volume of 0.42 ml/g. The micropore distribution curve had a maximum value having the largest differential pore volume value at a pore diameter of 0.3875 nm. The half-value width of the peak of the uniform mesopores in the mesopore distribution curve was 15 nm, and the center value was 17 nm. The pore volume of the uniform mesopores was 0.39 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 93%. In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. The micropore distribution curve of the obtained MFI zeolite is shown in FIG.

Using the obtained MFI-type zeolite as an aromatic compound production catalyst and n-butane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 18 shows the raw material gas flow time, the conversion rate, and the product yields. Until the raw material gas flow time of 44995 minutes, the conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range, and it was difficult to say stable production.

Comparative Example 10
Using the MFI-type zeolite obtained in Comparative Example 9 as an aromatic compound production catalyst and using n-hexane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 19 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 45995 minutes, and it was difficult to say that the production was stable.

Example 9
An amorphous aluminosilicate gel was added to and suspended in an aqueous solution of TPA hydroxide and sodium hydroxide. MFI-type zeolite was added to the obtained suspension as seed crystals to obtain a raw material composition. The amount of seed crystals added was 0.7% by weight based on the weight of Al ₂ O ₃ and SiO _{2 in} the raw material composition. Further, ethanol generated in the raw material composition was removed by evaporation.

The composition of the above raw material composition is as follows.
SiO ₂ /Al ₂ O ₃ molar ratio=44, TPA/Si molar ratio=0.05, Na/Si molar ratio=0.16, OH/Si molar ratio=0.21, H ₂ O/Si molar ratio= 10
The obtained raw material composition was sealed in a stainless steel autoclave and crystallized for 4 days while stirring at 115° C. to obtain a slurry-like mixed liquid. The crystallized slurry mixture was subjected to solid-liquid separation with a centrifugal sedimentation machine, solid particles were washed with a sufficient amount of pure water, and dried at 110°C to obtain a dry powder. Then, 10 g of the obtained dry powder was calcined at 550° C. for 1 hour, and then exchanged, filtered and washed in 100 ml of a 20 wt% ammonium chloride aqueous solution at 60° C. for 20 hours to obtain an ammonium-type MFI zeolite. Then, ammonium-type MFI-type zeolite was calcined at 550° C. for 1 hour to obtain MFI-type zeolite. The obtained MFI-type zeolite had an average particle diameter of 27 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 40, and an aggregate diameter of 46 μm, and the total pore volume of mesopores was 0.39 ml/g. Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.3875 nm. Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of MFI-type zeolite was 9 nm, and the center value was 16 nm. The pore volume of the uniform mesopores was 0.31 ml/g, and the proportion of the pore volume of the uniform mesopores in the total pore volume of the mesopores was 79%.

Steam treatment was applied to the obtained MFI-type zeolite. In the steam treatment, 30 vol% steam/air was supplied to the zeolite kept at 600° C. in a fixed bed for 10 minutes. After steam treatment, it was naturally cooled to obtain MFI-type zeolite.

The micropore distribution curve of the obtained MFI-type zeolite has an average particle diameter of 27 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 40, and an aggregate diameter of 46 μm, and the total mesopore volume is 0.39 ml/g. Met. Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.4125 nm. Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of MFI-type zeolite was 9 nm, and the center value was 16 nm. The pore volume of the uniform mesopores was 0.31 ml/g, and the proportion of the pore volume of the uniform mesopores in the total pore volume of the mesopores was 79%. In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. The micropore distribution curve of the obtained MFI zeolite is shown in FIG.

Using the obtained MFI-type zeolite as a catalyst for conversion to an aromatic compound and using n-butane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 20 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 44995 minutes.

Example 10
The MFI-type zeolite obtained in Example 9 was used as a conversion catalyst to an aromatic compound, and n-hexane was used as a raw material, and the conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 21 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 45995 minutes.

Comparative Example 11
MFI-type zeolite was obtained in the same manner as in Example 9 except that the steam treatment was not performed.

The obtained MFI-type zeolite had an average particle diameter of 27 nm, a SiO ₂ /Al ₂ O ₃ molar ratio of 40, and an aggregate diameter of 46 μm, and the total pore volume of mesopores was 0.39 ml/g. Further, the micropore distribution curve of the MFI-type zeolite had a maximum value having the largest differential pore volume value at 0.3875 nm. Further, the half-value width of the peak of the uniform mesopores in the pore distribution curve of MFI-type zeolite was 9 nm, and the center value was 16 nm. The pore volume of the uniform mesopores was 0.31 ml/g, and the proportion of the pore volume of the uniform mesopores in the total pore volume of the mesopores was 79%. In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected. The micropore distribution curve of the obtained MFI zeolite is shown in FIG.

Using the obtained MFI-type zeolite as a catalyst and n-butane as a raw material, a conversion reaction was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 22 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a constant value range until the raw material gas flow time of 44995 minutes, and it was difficult to say stable production.

Comparative Example 12
Using the MFI-type zeolite obtained in Comparative Example 11 as an aromatic compound production catalyst and using n-hexane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 23 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 45995 minutes, and it was difficult to say that the production was stable.

Example 11
Using the MFI-type zeolite obtained in Example 5 as a catalyst for conversion to an aromatic compound and using n-butane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 24 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 44995 minutes.

Example 12
The MFI-type zeolite obtained in Example 5 was used as a conversion catalyst to an aromatic compound, and n-hexane was used as a raw material, and the conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 25 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 45995 minutes.

Comparative Example 13
The MFI-type zeolite obtained in Comparative Example 5 was used as a conversion catalyst to an aromatic compound, and n-butane was used as a raw material, and the conversion reaction to an aromatic compound was performed under the same conditions as in Example 7.

Table 1 shows the gas circulation time in each step. Table 26 shows the raw material gas circulation time, the conversion rate, and the product yields. Until the raw material gas flow time of 44995 minutes, the conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range, and it was difficult to say stable production.

Comparative Example 14
Using the MFI-type zeolite obtained in Comparative Example 5 as an aromatic compound production catalyst and using n-hexane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 7.

Table 1 shows the gas circulation time in each step. Table 27 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 45995 minutes, and it was difficult to say that the production was stable.

Comparative Example 15
Using the MFI-type zeolite obtained in Comparative Example 7 as an aromatic compound production catalyst and using n-butane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 28 shows the raw material gas circulation time, the conversion rate, and the product yields. Until the raw material gas flow time of 44995 minutes, the conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range, and it was difficult to say stable production.

Comparative Example 16
Using the MFI-type zeolite obtained in Comparative Example 7 as an aromatic compound production catalyst and using n-hexane as a raw material, a conversion reaction to an aromatic compound was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 29 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 45995 minutes, and it was difficult to say that the production was stable.

Example 13
The MFI-type zeolite obtained in Example 7 was used as an aromatic compound production catalyst, and a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol% and isobutane 2 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition.

Table 1 shows the gas circulation time in each step.

Table 30 shows the raw material gas circulation time, the conversion rate, and the product yields. It was possible to obtain a stable product feed without significantly decreasing the conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 34995 minutes.

Example 14
The MFI-type zeolite obtained in Example 7 was used as an aromatic compound production catalyst, and a mixture of 1-butene 49 mol%, 2-butene 29 mol%, isobutene 10 mol%, n-butane 9 mol%, and isobutane 3 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in the present example is assumed to be a mixture obtained by removing a part of 1,3-butadiene and isobutene from a C4 fraction obtained by ordinary naphtha decomposition.

Table 1 shows the gas circulation time in each step. Table 31 shows the raw material gas circulation time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 35995 minutes.

Comparative Example 17
The MFI zeolite obtained in Comparative Example 9 was used as an aromatic compound production catalyst, and a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol% and isobutane 2 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition. Table 1 shows the gas circulation time in each step.

Table 32 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield were repeatedly increased and decreased within a certain range until the raw material gas flow time of 34995 minutes, and it was difficult to say that the production was stable.

Comparative Example 18
The MFI zeolite obtained in Comparative Example 9 was used as an aromatic compound production catalyst, and a mixture of 1-butene 49 mol%, 2-butene 29 mol%, isobutene 10 mol%, n-butane 9 mol% and isobutane 3 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in the present example is assumed to be a mixture obtained by removing a part of 1,3-butadiene and isobutene from a C4 fraction obtained by ordinary naphtha decomposition. Table 1 shows the gas circulation time in each step.

Table 33 shows the raw material gas flow time, conversion rate, and each product yield. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 35995 minutes, and it was difficult to say stable production.

Example 15
The MFI-type zeolite obtained in Example 9 was used as an aromatic compound production catalyst, and a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol%, and isobutane 2 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 34 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significant decrease in conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 34995 minutes.

Example 16
The MFI-type zeolite obtained in Example 9 was used as an aromatic compound production catalyst, and a mixture of 1-butene 49 mol%, 2-butene 29 mol%, isobutene 10 mol%, n-butane 9 mol%, and isobutane 3 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in the present example is assumed to be a mixture obtained by removing a part of 1,3-butadiene and isobutene from a C4 fraction obtained by ordinary naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 35 shows the raw material gas circulation time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 35995 minutes.

Comparative Example 19
Using the MFI-type zeolite obtained in Comparative Example 11 as a catalyst, a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol% and isobutane 2 mol% was used as a raw material, and the same as in Example 1. The conversion reaction was carried out under the conditions of. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition. Table 1 shows the gas circulation time in each step.

Table 36 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield were repeatedly increased and decreased within a certain range until the raw material gas flow time of 34995 minutes, and it was difficult to say that the production was stable.

Comparative Example 20
The MFI-type zeolite obtained in Comparative Example 11 was used as an aromatic compound production catalyst, and a mixture of 1-butene 49 mol%, 2-butene 29 mol%, isobutene 10 mol%, n-butane 9 mol%, and isobutane 3 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in the present example is assumed to be a mixture obtained by removing a part of 1,3-butadiene and isobutene from a C4 fraction obtained by ordinary naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 37 shows the raw material gas circulation time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 35995 minutes, and it was difficult to say stable production.

Example 17
The MFI zeolite obtained in Example 5 was used as an aromatic compound production catalyst, and a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol% and isobutane 2 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 38 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significant decrease in conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 34995 minutes.

Example 18
The MFI-type zeolite obtained in Example 5 was used as an aromatic compound production catalyst, and a mixture of 1-butene 49 mol%, 2-butene 29 mol%, isobutene 10 mol%, n-butane 9 mol%, and isobutane 3 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in the present example is assumed to be a mixture obtained by removing a part of 1,3-butadiene and isobutene from a C4 fraction obtained by ordinary naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 39 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 35995 minutes.

Comparative Example 21
Using the MFI-type zeolite obtained in Comparative Example 5 as a catalyst, a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol% and isobutane 2 mol% was used as a raw material, and the same as Example 1. The conversion reaction was carried out under the conditions of. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 40 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield were repeatedly increased and decreased within a certain range until the raw material gas flow time of 34995 minutes, and it was difficult to say that the production was stable.

Comparative Example 22
The MFI zeolite obtained in Comparative Example 5 was used as an aromatic compound production catalyst, and a mixture of 1-butene 49 mol%, 2-butene 29 mol%, isobutene 10 mol%, n-butane 9 mol% and isobutane 3 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in the present example is assumed to be a mixture obtained by removing a part of 1,3-butadiene and isobutene from a C4 fraction obtained by ordinary naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 41 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 35995 minutes, and it was difficult to say stable production.

Comparative Example 23
The MFI zeolite obtained in Comparative Example 7 was used as an aromatic compound production catalyst, and a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol%, and isobutane 2 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 42 shows the raw material gas circulation time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield were repeatedly increased and decreased within a certain range until the raw material gas flow time of 34995 minutes, and it was difficult to say that the production was stable.

Comparative Example 24
The MFI zeolite obtained in Comparative Example 7 was used as an aromatic compound production catalyst, and a mixture of 1-butene 49 mol%, 2-butene 29 mol%, isobutene 10 mol%, n-butane 9 mol%, and isobutane 3 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in the present example is assumed to be a mixture obtained by removing a part of 1,3-butadiene and isobutene from a C4 fraction obtained by ordinary naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 43 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 35995 minutes, and it was difficult to say stable production.

Example 19
The MFI zeolite obtained in Example 7 was used as an aromatic compound production catalyst, and a mixture of 1-hexene 50 mol% and 2-hexene 50 mol% was used as a raw material to produce an aromatic compound under the same conditions as in Example 1. went.
Table 1 shows the gas circulation time in each step.

Table 44 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to obtain a stable product feed without significant decrease in conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 24995 minutes.

Example 20
The MFI-type zeolite obtained in Example 7 was used as an aromatic compound production catalyst, a mixture of 50 mol% of 1-hexene and 50 mol% of n-hexane was used as a raw material, and a conversion reaction was performed under the same conditions as in Example 1. It was

Table 1 shows the gas circulation time in each step. Table 45 shows the raw material gas circulation time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 42595 minutes.

Comparative Example 25
The MFI zeolite obtained in Comparative Example 9 was used as an aromatic compound production catalyst, a mixture of 1-hexene 50 mol% and 2-hexene 50 mol% was used as a raw material, and the conversion reaction was performed under the same conditions as in Example 1. Table 1 shows the gas circulation time in each step.

Table 46 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 24995 minutes, and it was difficult to say that the production was stable.

Comparative Example 26
The MFI-type zeolite obtained in Comparative Example 9 was used as an aromatic compound production catalyst, a mixture of 50 mol% of 1-hexene and 50 mol% of n-hexane was used as a raw material, and a conversion reaction was performed under the same conditions as in Example 1. Table 1 shows the gas circulation time in each step.

Table 47 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 42595 minutes, and it was difficult to say that the production was stable.

Example 21
Using the MFI-type zeolite obtained in Example 9 as an aromatic compound production catalyst and using a mixture of 50 mol% of 1-hexene and 50 mol% of 2-hexene as a raw material, a conversion reaction was carried out under the same conditions as in Example 1. Table 1 shows the gas circulation time in each step. Table 48 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 24995 minutes.

Example 22
Using the MFI-type zeolite obtained in Example 9 as an aromatic compound production catalyst and using a mixture of 50 mol% of 1-hexene and 50 mol% of n-hexane as a raw material, a conversion reaction was performed under the same conditions as in Example 1. Table 1 shows the gas circulation time in each step. Table 49 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, the benzene yield, the toluene yield, and the xylene yield until the raw material gas flow time of 42595 minutes.

Comparative Example 27
Using the MFI-type zeolite obtained in Comparative Example 11 as a catalyst, a mixture of 1-hexene 50 mol% and 2-hexene 50 mol% was used as a raw material, and the conversion reaction was performed under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 50 shows the raw material gas circulation time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 24995 minutes, and it was difficult to say that the production was stable.

Comparative Example 28
The MFI zeolite obtained in Comparative Example 11 was used as an aromatic compound production catalyst, a mixture of 50 mol% of 1-hexene and 50 mol% of n-hexane was used as a raw material, and the conversion reaction was performed under the same conditions as in Example 1. Table 1 shows the gas circulation time in each step. Table 51 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 42595 minutes, and it was difficult to say stable production.

Example 23
Using the MFI-type zeolite obtained in Example 5 as an aromatic compound production catalyst and using a mixture of 1-hexene 50 mol% and 2-hexene 50 mol% as a raw material, an aromatic compound was prepared under the same conditions as in Example 1. The conversion reaction was carried out.

Table 1 shows the gas circulation time in each step. Table 52 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to obtain a stable product feed without significant decrease in conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 24995 minutes.

Example 24
Using the MFI-type zeolite obtained in Example 5 as a catalyst for producing an aromatic compound and using a mixture of 50 mol% of 1-hexene and 50 mol% of n-hexane as a raw material, an aromatic compound was prepared under the same conditions as in Example 1. The conversion reaction was carried out.

Table 1 shows the gas circulation time in each step. Table 53 shows the raw material gas circulation time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significantly decreasing the conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 42595 minutes.

Comparative Example 29
Using the MFI-type zeolite obtained in Comparative Example 5 as a catalyst, a mixture of 50 mol% of 1-hexene and 50 mol% of 2-hexene as a raw material was subjected to a conversion reaction under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step.

Table 54 shows the raw material gas circulation time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 24995 minutes, and it was difficult to say that the production was stable.

Comparative Example 30
Using the MFI-type zeolite obtained in Comparative Example 5 as an aromatic compound production catalyst and using a mixture of 50 mol% of 1-hexene and 50 mol% of n-hexane as a raw material, an aromatic compound was prepared under the same conditions as in Example 1. The conversion reaction was carried out.

Table 1 shows the gas circulation time in each step. Table 55 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 42595 minutes, and it was difficult to say that the production was stable.

Comparative Example 31
Using the MFI-type zeolite obtained in Comparative Example 7 as an aromatic compound production catalyst and using a mixture of 50 mol% of 1-hexene and 50 mol% of 2-hexene as a raw material, an aromatic compound was prepared under the same conditions as in Example 1. The conversion reaction was carried out.

Table 1 shows the gas circulation time in each step.

Table 56 shows the raw material gas circulation time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 24995 minutes, and it was difficult to say that the production was stable.

Comparative Example 32
Using the MFI-type zeolite obtained in Comparative Example 7 as an aromatic compound production catalyst and using a mixture of 50 mol% of 1-hexene and 50 mol% of n-hexane as a raw material, an aromatic compound was prepared under the same conditions as in Example 1. The conversion reaction was carried out.

Table 1 shows the gas circulation time in each step. Table 57 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 42595 minutes, and it was difficult to say that the production was stable.

Example 25
Aluminum hydroxide was dissolved in an aqueous solution of TPA bromide and sodium hydroxide. Tetraethoxysilane was added to and suspended in the obtained aqueous solution. MFI-type zeolite was added to the obtained suspension as seed crystals to obtain a raw material composition. The generated ethanol was removed by evaporation.

The composition of the above raw material composition is as follows.
SiO ₂ /Al ₂ O ₃ molar ratio=63, TPA/Si molar ratio=0.05, Na/Si molar ratio=0.17, OH/Si molar ratio=0.17, H ₂ O/Si molar ratio= 10
This raw material composition was reacted and treated in the same manner as in Example 1 to obtain an MFI type zeolite. The obtained MFI zeolite had an average particle diameter of 57 nm and a SiO ₂ /Al ₂ O ₃ molar ratio of 62. The total pore volume of mesopores present in the obtained MFI-type zeolite was 0.14 ml/g.

Further, the half value width of the peak of the uniform mesopores in the pore distribution curve of the obtained MFI-type zeolite was 6 nm, and the center value was 10 nm. The pore volume of the uniform mesopores was 0.16 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 44%.
In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected.

Using the obtained MFI-type zeolite as an aromatic compound production catalyst and ethylene as a raw material, a conversion reaction to an aromatic compound was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 58 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to obtain a stable product feed without significant decrease in conversion, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 8995 minutes.

Example 26
The MFI-type zeolite obtained in Example 25 was used as an aromatic compound production catalyst, and a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol%, and isobutane 2 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 59 shows the raw material gas flow time, the conversion rate, and the product yields. It was possible to stably obtain the product feed without significant decrease in conversion rate, benzene yield, toluene yield, and xylene yield until the raw material gas flow time of 34995 minutes.

Comparative Example 33
An MFI zeolite was obtained in the same manner as in Example 25 except that the steam treatment was not performed.

The obtained MFI zeolite had an average particle diameter of 57 nm and a SiO ₂ /Al ₂ O ₃ molar ratio of 62. The total pore volume of mesopores present in the obtained MFI-type zeolite was 0.14 ml/g.

Further, the half value width of the peak of the uniform mesopores in the pore distribution curve of the obtained MFI-type zeolite was 6 nm, and the center value was 10 nm. The pore volume of the uniform mesopores was 0.16 ml/g, and the proportion of the pore volume of the uniform mesopores to the total pore volume of the mesopores was 44%.
In addition, powder X-ray diffraction of the obtained MFI-type zeolite has no peak in the range of 0.1 to 3 degrees, which shows that the mesopores are irregularly connected.

Using the obtained MFI-type zeolite as an aromatic compound production catalyst and ethylene as a raw material, a conversion reaction to an aromatic compound was carried out under the same conditions as in Example 1.

Table 1 shows the gas circulation time in each step. Table 60 shows the raw material gas flow time, the conversion rate, and the product yields. The conversion rate, benzene yield, toluene yield, and xylene yield repeatedly increased and decreased within a certain range until the raw material gas flow time of 8995 minutes, and it was difficult to say that the production was stable.

Comparative Example 34
The MFI-type zeolite obtained in Example 33 was used as an aromatic compound production catalyst, and a mixture of 1-butene 29 mol%, 2-butene 17 mol%, isobutene 47 mol%, n-butane 5 mol% and isobutane 2 mol% was used as a raw material. The conversion reaction was carried out under the same conditions as in Example 1. In addition, the raw material composition used in this example is assumed to be a mixture obtained by removing 1,3-butadiene from a C4 fraction obtained by the usual naphtha decomposition. Table 1 shows the gas circulation time in each step. Table 61 shows the raw material gas circulation time, the conversion rate, and each product yield. The conversion rate, benzene yield, toluene yield, and xylene yield were repeatedly increased and decreased within a certain range until the raw material gas flow time of 34995 minutes, and it was difficult to say that the production was stable.

The catalyst for producing an aromatic compound of the present invention contains an MFI-type zeolite characterized by mesopores so that an aromatic compound can be produced from a hydrocarbon raw material such as a lower olefin, a saturated aliphatic hydrocarbon or an alicyclic hydrocarbon. When producing, a specific long catalyst life is exhibited, an excellent productivity and a stable production method can be realized, and it is industrially very useful.

It is a micropore distribution curve of the MFI type zeolite obtained by Examples 1-4 and Comparative Examples 1-4. It is a micropore distribution curve of the MFI-type zeolite obtained by Examples 5-6 and Comparative Examples 5-8. It is a micropore distribution curve of the MFI zeolite obtained by Examples 7-10 and Comparative Examples 9-12.

Claims (14)

An aromatic compound-producing catalyst comprising an MFI-type zeolite satisfying the following characteristics (i) to (iv).
(I) The mesopore distribution curve has a peak, the full width at half maximum (hw) of the peak is hw≦20 nm, and the center value (μ) of the peak is 10 nm≦μ≦20 nm, which corresponds to the peak. The mesopore volume (pv) of the mesopores is 0.05 ml/g≦pv.
(Ii) It has no peak in the range of 0.1 to 3 degrees in powder X-ray diffraction measurement with a diffraction angle of 2θ.
(Iii) The average particle diameter (PD) is PD≦100 nm.
(Iv) a differential pore volume value in the range of 0.8nm from pore diameter _{0.3nm (dV P / d (d} P)) - distribution curve of micropores has a maximum value, the most differentiated fine in the range of pore diameter 0.4~0.5nm showing a large value of pore volume value _{(dV P / d (d P} )). The aromatic compound-producing catalyst according to claim 1, comprising an MFI-type zeolite having a mesopore group having a half width of hw≦15 nm shown in (i) above. A MFI-type zeolite having a mesopore group in which the ratio (pvr) of the pore volume to the total mesopore volume of pv shown in (i) above is 30%≦pvr≦100% is included. The aromatic compound production catalyst according to claim 1 or 2. The aromatic compound according to any one of claims 1 to 3, comprising an MFI zeolite obtained by steaming an MFI zeolite satisfying the characteristics described in (i) to (iii) above. catalyst. SiO ₂ /Al ₂ O ₃ (molar ratio) comprises 20≦SiO ₂ /Al ₂ O ₃ ≦200 MFI type zeolite, characterized in that the aromatic compound production according to any one of claims 1 to 4. catalyst. It is for swing operation, The aromatic compound manufacturing catalyst in any one of Claims 1-5 characterized by the above-mentioned. The catalyst for producing an aromatic compound according to any one of claims 1 to 6, which is for converting an aromatic compound of a saturated aliphatic hydrocarbon or an alicyclic hydrocarbon having 2 to 6 carbon atoms. A method for producing an aromatic compound, which comprises bringing the aromatic compound production catalyst according to any one of claims 1 to 6 into contact with a hydrocarbon having 2 to 6 carbon atoms to form an aromatic compound. The method for producing an aromatic compound according to claim 8, wherein the hydrocarbon having 2 to 6 carbon atoms is a lower olefin containing at least one selected from the group consisting of olefins having 2 to 6 carbon atoms. The method for producing an aromatic compound according to claim 8, wherein the hydrocarbon having 2 to 6 carbon atoms is a hydrocarbon mixture having 4 and/or 6 carbon atoms. The method for producing an aromatic compound according to claim 10, wherein the hydrocarbon mixture having 4 carbon atoms and/or 6 carbon atoms is a fraction produced by naphtha pyrolysis. The method for producing an aromatic compound according to claim 8, wherein the hydrocarbon having 2 to 6 carbon atoms is a saturated aliphatic hydrocarbon or an alicyclic hydrocarbon having 2 to 6 carbon atoms. The method for producing an aromatic compound according to any one of claims 8 to 12, wherein the aromatic compound contains at least one selected from the group consisting of benzene, toluene, and xylene. A plurality of reaction fields having the aromatic compound-producing catalyst according to any one of claims 1 to 7, wherein at least one reaction field is made into an aromatic compound by a swing operation for regenerating the aromatic compound-producing catalyst. The method for producing an aromatic compound according to any one of claims 8 to 13, which is characterized in that.

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