JP2021109132A - Catalyst for producing aromatic compound - Google Patents

Abstract

To provide a catalyst for producing an aromatic compound having excellent heat resistance, hydrothermal resistance and productivity suitable for industrial use.SOLUTION: There is provided a catalyst for producing an aromatic compound, which is a molded body comprising a 10-membered ring pore zeolite and a binder, wherein silver is supported as an active metal and a ratio of an ammonia desorption amount at 500 to 750°C to an ammonia desorption amount at 350 to 500°C in a temperature programmed desorption method with ammonia adsorption is 15wt% to 50wt%. The 10-membered ring pore zeolite satisfies following requirements: (i) a mesopore volume is 0.05 cc/g or more; (ii) a mesopore exhibits a distribution having a peak, and the half width (hw) of the peak is hw≤40 nm and a central value (μ) of the peak is 5 nm≤μ≤30 nm; and (iii) a macropore in the range of 0.2 to 200 μm has a macropore volume of 0.03 to 0.30 cc/g. The 10-membered ring pore zeolite constituting the catalyst for producing an aromatic compound is an MFI type zeolite or an MEL type zeolite.SELECTED DRAWING: None

Description

The present invention relates to a catalyst for producing an aromatic compound used for producing an aromatic hydrocarbon from a lower hydrocarbon, and more specifically, it is suitable for industrial use because it carries silver and has specific properties. It relates to a catalyst for producing an aromatic compound having excellent heat resistance, hydrothermal resistance and high productivity.

Medium-pore zeolite is used as a highly selective catalyst utilizing pores of a size equivalent to that of an aromatic compound. Examples of using MFI-type zeolite as a catalyst, which is a typical medium-pore zeolite, include toluene disproportionation (see, for example, Patent Document 1), xylene isomerization (see, for example, Patent Document 2), and aliphatic. Aromatization of hydrocarbons (see, for example, Patent Document 3) and the like can be mentioned. These reactions mainly utilize the characteristics of the micropores of medium-pore zeolite. The micropores of the medium-pore zeolite have an inlet diameter of about 0.5 nm, and are considered to be an effective reaction field for molecules having a molecular diameter close to the pore diameter.

On the other hand, these reactions are generally carried out under high temperature conditions exceeding 500 ° C. In that case, the acidity of the zeolite, not limited to the surface or the inside, decreases with time by heating or dealumination in a hydrothermal atmosphere. This phenomenon is an unavoidable problem when zeolite is used as a catalyst. In particular, dealuminum removal in a hydrothermal atmosphere occurs in a catalyst regeneration step in which coke is burned in an atmosphere containing oxygen with respect to the catalyst after coke precipitation, and is a cause of deactivating the catalyst.

As one method of suppressing such dealumination of zeolite, a method of improving the water heat resistance of zeolite by supporting phosphorus after supporting aluminum on the zeolite has been proposed (see, for example, Patent Document 4). .)
Further, as another method, for example, a method of improving the heat resistance and water heat resistance of zeolite by containing silver in zeolite to protect the acid point has been proposed (see, for example, Non-Patent Document 1).

Patent No. 401479 Patent No. 2598127 Patent No. 2905947 JP 2013-184108

Physical Chemistry Chemical Physics Vol. 17, p. 15637 (2015)

However, in the method proposed in Patent Document 4, the selectivity of the aromatic compound is low, and there is a problem in productivity. In addition, in industrial use, it is common to repeat the formation reaction and regeneration to remove by-product cork, and it is required to suppress the deactivation of the catalyst in this process, but no consideration is given to this point. do not have.

Further, in the method proposed in Non-Patent Document 1, although the heat resistance and water heat resistance of zeolite are improved, the amount of silver supported and the dispersed state are not sufficiently studied, and the catalyst is suitable for industrial use. It had a problem.

Therefore, as a result of diligent studies to solve the above problems, the present inventors have determined that the peak area value of the ammonia adsorption temperature rise desorption analysis is within a certain range, so that silver is highly dispersed on the zeolite. The present invention has been completed by finding that it becomes a dispersed catalyst and becomes a catalyst for producing an aromatic compound having excellent heat resistance, water heat resistance, and productivity suitable for industrial use.

That is, the present invention is a molded product containing 10-membered ring-pore zeolite and a binder, which supports silver as an active metal and has 500 to 500 to 500 ° C. with respect to the amount of ammonia desorption at 350 to 500 ° C. in the ammonia adsorption heated desorption analysis. The present invention relates to a catalyst for producing an aromatic compound, wherein the ratio of the amount of ammonia desorbed at 750 ° C. is 15 wt% to 50 wt%.

Hereinafter, the present invention will be described in detail.

The catalyst for producing an aromatic compound of the present invention is a molded product containing 10-membered ring-pore zeolite and a binder, and supports silver as an active metal. The 10-membered ring-pore zeolite may be any zeolite having a 10-membered ring structure and pores, and the zeolite having the 10-membered ring-pore structure is specifically AEL. Examples of zeolites such as EUO, FER, HEU, MEU, MEL, MFI, and NES types can be mentioned, and since they are particularly expected as an aromatization catalyst for aliphatic hydrocarbons, MFI type zeolites or MEL type zeolites can be used. It is preferable to have. And, for example, as the MFI type zeolite, an aluminosilicate compound belonging to the structure code MFI defined by the International Zeolite Society can be mentioned.

Since the 10-membered ring-pore zeolite has excellent productivity, particularly as a catalyst for producing an aromatic compound, the mesopores satisfying the following characteristics (i) to (ii) and the mesopores. It is preferable that it has macropores that satisfy the following characteristics (iii).
(I) The mesopore volume is 0.05 cc / g or more.
(Ii) The mesopores show a distribution having a peak, the full width at half maximum (hw) of the peak is hw ≦ 40 nm, and the center value (μ) of the peak is 5 nm ≦ μ ≦ 30 nm.
(Iii) The macropore volume of the macropores in the range of 0.2 to 200 μm in diameter is 0.03 cc / g or more and 0.30 cc / g or less.

The 10-membered ring-pore zeolite is excellent in diffusion of a substrate and excellent in expected effects such as catalytic performance and adsorption performance. Therefore, a mesopore volume of 0.05 cc / g or more is preferable, and particularly Since it is expected as an excellent catalyst for producing an aromatic compound, it is preferably 0.10 cc / g or more. Further, since the expected effects such as catalyst performance and adsorption performance are excellent, the mesopores show a distribution having a peak, and hw ≦ 40 nm, particularly hw ≦ 30 nm, and μ is 5 nm ≦ μ. It is preferably ≦ 30 nm, particularly 10 nm ≦ μ ≦ 20 nm. Further, it also has macropores, and the macropore volume of the macropores having a diameter in the range of 0.2 to 200 μm is 0.03 cc / g or more and 0.30 cc / g or less, particularly 0.03 cc / g or more and 0. It is preferably 20 cc / g or less.

The 10-membered ring-pore zeolite _{may have any SiO 2} / Al ₂ O ₃ ratio as long as it belongs to the category called zeolite, and among them, it is particularly excellent in heat resistance and durability. since the things are _preferably those which are SiO 2 / _Al 2 _{O 3} ratio = 20 to 300, further _SiO 2 / _Al 2 _{O 3} ratio = 30 to 200 preferred.

As a method for producing the 10-membered ring-pore zeolite, a generally known method can be used. Specifically, it can be produced by mixing a compound containing an alkali metal and / or an alkaline earth metal as a cation, an organic structure-directing agent and an aluminosilicate gel, and calcining the obtained crystal product. Examples of the compound containing an alkali metal and an alkaline earth metal at that time include sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide and the like, and sodium hydroxide is particularly preferable. Examples of the organic structure-directing agent include tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and tetraethylammonium hydroxide. Moreover, as an aluminosilicate gel, for example, an amorphous aluminosilicate gel and the like can be mentioned.

Further, a method in which ion exchange is performed before firing the crystal obtained as described above, a part or all of the crystal obtained during firing is subjected to hydrothermal treatment, and then further ion exchange is performed, and the crystal obtained as described above is fired. After that, ion exchange is performed to obtain a proton-type zeolite, which is then calcined in a hydrothermal atmosphere, or the like.

As the firing conditions at that time, the treatment temperature is preferably 300 to 900 ° C, particularly preferably 400 to 700 ° C. The treatment time is industrially preferably 5 minutes to 25 hours. The atmosphere may also include, for example, nitrogen, air, oxygen, argon, or any other combination of one or more of the inert gases. Then, by performing a hydrothermal (steam) treatment in part or all of the firing step, the aluminum at the Bronsted acid (hereinafter, may be referred to as B acid) point is desorbed. The treatment temperature of the hydrothermal treatment is preferably 400 to 750 ° C, particularly preferably 500 to 650 ° C. The water vapor concentration is preferably 5 to 100%, particularly preferably 10 to 80%.

The ion exchange is performed before and after the firing step, and may be divided into a plurality of ion exchanges. Further, the ion exchange includes ion exchange using an acid such as ammonium chloride, hydrochloric acid and nitric acid, and those using hydrochloric acid and nitric acid are preferable. In addition, ion exchange can be replaced by washing with water.

The binder constituting the catalyst for producing an aromatic compound of the present invention may be generally used as a binder in combination with zeolite, and examples thereof include silica, alumina-silica, alumina, titania, and calcium carbonate. Of these, silica is preferable because it is easy to form a catalyst for producing an aromatic compound, which is particularly excellent in catalytic performance. The silica at that time may be any silica as long as it belongs to the category called silica, and may have a specific crystal structure or may be amorphous. Furthermore, there are no restrictions on the particle size, aggregation diameter, etc. of silica.

The mixing ratio of the 10-membered ring-pore zeolite and the binder is arbitrary, and the 10-membered ring-pore is a catalyst for producing an aromatic compound showing particularly excellent catalyst performance, handleability, and catalyst life. Zeolite: binder = 50 to 95:50 to 5 (weight ratio) is preferable, and 60 to 90:40 to 10 is particularly preferable.

Further, the shape of the molded body is arbitrary, and examples thereof include a spherical shape, an elliptical shape, a columnar shape, a cylindrical shape, a polygonal columnar shape, a hollow polygonal pillar shape, and the like, and a cylindrical shape and a cylindrical shape are particularly preferable.

The catalyst for producing an aromatic compound of the present invention is obtained by supporting silver as an active metal in a molded product containing the 10-membered ring-pore zeolite and a binder. Any method can be used as the method for supporting silver at that time, and examples thereof include a method in which the molded product is impregnated with silver nitrate or the like, supported by impregnation, ion exchange, or the like.

In the catalyst for producing an aromatic compound of the present invention, the ratio of the amount of ammonia desorbed at 500 to 750 ° C. to the amount of desorbed ammonia at 350 to 500 ° C. as measured by the ammonia adsorption heated desorption analysis is 15 wt% or more. It is in the range of 50 wt%, and in particular, silver is highly dispersed, and the heat resistance, water heat resistance, and production yield of aromatic compounds are excellent. Therefore, with respect to the amount of ammonia desorbed at 350 to 500 ° C. It is preferable that the ratio of the amount of ammonia desorbed at 500 to 750 ° C. is in the range of 15 wt% to 40 wt%. Here, when the ratio of the amount of ammonia desorbed at 500 to 750 ° C. to the amount of ammonia desorbed at 350 to 500 ° C. is less than 15 wt%, the support of silver becomes insufficient, and there is a problem in heat resistance and water heat resistance. To have. On the other hand, if it exceeds 50 wt%, the dispersion of silver becomes non-uniform, the caulking resistance is inferior, and the deactivation rate as a catalyst becomes high, so that there is a problem in productivity.

The ammonia adsorption temperature-temperature desorption analysis in the present invention has no limitation, and for example, a solid catalyst by ammonia temperature-temperature desorption analysis using a temperature-temperature desorption gas analyzer (hereinafter, may be referred to as TPD). It can be measured by a method according to an acid property analysis (see, for example, catalyst, vol.42, p.218 (2000)). Specifically, ammonia is saturated and adsorbed on a catalyst for producing an aromatic compound at room temperature, heated to 100 ° C. to remove ammonia remaining in the measurement atmosphere, and then 700 ° C. at a heating rate of 10 ° C./min. A method of raising the temperature up to the above, measuring the amount of ammonia desorbed over time in the process, and using the desorbed amount as the amount of solid acid can be mentioned. In the present invention, the change in the amount of ammonia desorbed at the measured temperature by the ammonia adsorption heated desorption analysis, particularly the ratio of the amount of ammonia desorbed at 500 to 750 ° C. to the amount of ammonia desorbed at 350 to 500 ° C. is silver. It was found that it was caused by the carrying state (silver distribution state).

The catalyst for producing an aromatic compound of the present invention makes it possible to produce an aromatic compound particularly efficiently by, for example, contacting a hydrocarbon having 4 to 6 carbon atoms as a raw material. Since the aromatic compound can be produced with higher efficiency, the hydrocarbon preferably contains 20% by mass or more, more preferably 50% by mass or more, and further preferably 70% by mass of hydrocarbons having 4 to 6 carbon atoms. .. At that time, any hydrocarbon having 4 to 6 carbon atoms can be mentioned as long as it belongs to the category, for example, saturated aliphatic hydrocarbons, unsaturated aliphatic hydrocarbons, alicyclic hydrocarbons and the like. Aliphatic hydrocarbons, mixtures thereof and the like can be mentioned, and more specifically, 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. Further, in some cases, the other raw material component contained in the raw material may be any compound as long as it contains a carbon component, for example, a hydrocarbon having 1 to 3 carbon atoms and a hydrocarbon having 7 to 15 carbon atoms. Examples include hydrogen, oxygen-containing compounds (alcohol, ether, carboxylic acid, ketone, etc.), and nitrogen-containing compounds (amine, etc.). From the viewpoint of efficiently producing aromatic compounds, hydrocarbons or carbons having 1 to 3 carbon atoms. It is preferably a hydrocarbon having a number of 7 to 10.

Then, in the production of the aromatic compound, the reaction temperature is 400 to 800 ° C. because it is an efficient production method of the aromatic compound which suppresses the by-production of olefins or alkanes and does not require an unnecessarily heat-resistant reaction device. Range is desirable. Further, the reaction pressure is not limited, and the operation can be performed in a pressure range of, for example, about 0.05 MPa to 5 MPa. The supply of the reaction raw material to the catalyst for producing the aromatic compound is not particularly limited as the ratio of the volume of the raw material gas to the catalyst volume, and for example, an air velocity of about ^{1h -1 to} 50,000h ^{-1 is given.} be able to. When supplying a hydrocarbon as a raw material gas, a single gas of a specific hydrocarbon, a mixed gas, and a single or mixed gas selected from an inert gas such as nitrogen, hydrogen, carbon monoxide, and carbon dioxide. It can also be used as diluted with.

There are no restrictions on the reaction form when producing aromatic compounds, for example, fixed bed, transport bed, fluidized bed, moving bed, multi-tube reactor as well as continuous flow type, intermittent flow type and swing type reactor. Etc. can be used.

The aromatic compound to be 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, etc. Methylnaphthalene and the like can be mentioned, and benzene, toluene and xylene are particularly preferable.

The catalyst for producing an aromatic compound of the present invention is expected to be industrially useful because it has excellent heat resistance, water heat resistance, and productivity.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples.

The 10-membered ring-pore zeolite used in Examples and Comparative Examples was prepared based on Japanese Patent No. 60070336. The catalyst for producing zeolite and aromatic compound was measured by the following method.

~ Method for quantifying the amount of silver carried ~
An ICP device ((trade name) Optima 8300, manufactured by PerkinElmer Co., Ltd.) was used for measuring the amount of silver carried. After the sample was precisely weighed in a 100 ml volumetric flask, hydrofluoric acid, nitric acid and ultrapure water were added and allowed to dissolve overnight. After the volumetric flask, the sample was sampled, ICP-AES was measured, and the amount of silver carried was calculated from the calibration curve.

~ Measurement of mesopore distribution, pore diameter, and volume ~
The mesopore distribution and mesopore diameter were measured by nitrogen adsorption / desorption measurement.

As the nitrogen adsorption / desorption measurement at that time, a nitrogen adsorption / desorption device ((trade name) OMNISORP360CX, manufactured by Beckman Coulter) was used, and both adsorption and desorption were measured under the condition of 30 torr / step.

Then, the desorption process of the nitrogen adsorption / desorption measurement was analyzed by the Barret-Joiner-Halenda method (Journal of the American Chemical Society, 1951, pp. 373-380). A mesopore distribution curve, which is a differential value of the amount of desorption of moth, was obtained. Peakfit (ver. 4.12) manufactured by HULINKS was used for the analysis of the mesopore distribution curve.

The mesopore volume was determined by integrating the amount of nitrogen gas desorption in the range of 2 nm or more and 50 nm or less. Then, among the peaks of the differential value (d (V / m) / d (D)) of the amount of nitrogen gas desorbed from the mesopores at the mesopore diameter value, the largest 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 median value of the Gaussian function (that is, the peak center value of the pore distribution) (μ) are uniformly meso-meso. Defined as pores.

~ Measurement of macropore volume ~
Using a mercury porosimeter ((trade name) POREMASTER GT, manufactured by Quantachrome Instruments), about 0.6 g of a sample was introduced into a measurement cell (0.5 cc glass cell), and the amount of mercury injection under each measurement pressure was measured. .. The mercury injection amount was obtained by subtracting the mercury injection amount based on the injection amount at the time of measurement of the blank cell. The macropore volume in the range of 0.2 to 200 μm in diameter was obtained by integrating the press-fitting amount in the diameter range of 0.2 to 200 μm among the mercury injecting amounts obtained from the above. The analysis of the macropore volume was performed by analysis software ((trade name) Polemaster for Windows R, manufactured by Quantachrome Instruments). The surface tension of mercury was 480 erg / cm ² , and the advancing angle of mercury was 140 °.

~ Ammonia adsorption temperature rise desorption analysis ~
Ammonia adsorption temperature rise desorption analysis is performed by a general NH _3- TPD device ((trade name) BELCATII, manufactured by Microtrack Bell Co., Ltd.) and a gas analyzer ((trade name) BELMass, manufactured by Microtrack Bell Co., Ltd.). Was used. The sample was granulated, placed in a cell, heated to 500 ° C. at 10 ° C./min under a helium atmosphere, and held for 1 hour. Then, the temperature was lowered to 100 ° C., and 0.2% ammonia gas was introduced for 30 minutes. The temperature was raised to 600 ° C. at 10 ° C./min, and the desorbed ammonia was analyzed with a gas analyzer. The amount of ammonia desorbed at 350 ° C. to 500 ° C. and the amount of ammonia desorbed at 500 to 750 ° C. were calculated, and the ratios were calculated.

~ Water heat resistance evaluation test conditions ~
Using the catalysts obtained in Examples and Comparative Examples, the water heat resistance was evaluated by the following method.

A 5 g sample was placed on a magnetic dish, placed in a muffle furnace, and heated to 600 ° C. over 3 hours. Water at 25 ° C. was circulated in the muffle furnace at a rate of 0.5 ml / min. At that time, air was used as the companion gas, and the gas was circulated at a rate of 1000 ml / min. After 1 hour, the flow of water was stopped and the temperature was naturally lowered to room temperature. The sample taken out from the furnace was measured by the above acid amount measuring method, and the acid amount of the sample was calculated. The acid amount maintenance rate was calculated using the following formula.
Acid amount maintenance rate = (acid amount after test) / (acid amount before test) x 100
~ Aromatic compound manufacturing equipment and its manufacturing method ~
Using the catalysts obtained in Examples and Comparative Examples, aromatic compounds were produced by the following methods, and their performance as catalysts for producing aromatic compounds was evaluated.

A fixed-bed gas-phase flow reactor having a stainless steel reaction tube (inner diameter 16 mm, length 600 mm) was used. The middle stage of the stainless steel reaction tube was filled with a sample, pretreated by heating under a dry air flow, and then the raw material gas was fed. Then, a ceramic tube furnace was used for heating, and the temperature of the catalyst (mold) layer was controlled. The reaction outlet gas and the reaction solution were collected, and the gas component and the liquid component were analyzed individually using a gas chromatograph. The gas component is a gas chromatograph (manufactured by Shimadzu Corporation, (trade name) GC) equipped with a TCD detector and having a filler (manufactured by Waters, (trade name) PorapakQ or GL Science, (trade name) MS-5A). -1700) was used for analysis. The liquid components were analyzed using a gas chromatograph (manufactured by Shimadzu Corporation, (trade name) GC-2015) equipped with a FID detector and having a capillary column (manufactured by GL Science, Inc. (trade name) TC-1) as a separation column. ..

The reaction conditions were set as follows.

(Aromatic compound production conditions)
Catalyst weight: 0.5 g.
Flowing gas: Mixed gas of 55 mol% of raw material gas + 45 mol% of nitrogen Raw material gas: Isobutane 2 Nml / min, Normal butene 9 Nml / min, 2-Butene 12 Nml / min, 1-Butene 21 Nml / min, Isobutene 6 Nml / min, Propane 9 Nml / min Minute reaction temperature: 600 ° C.
Reaction time: 24 hours.

After a 24-hour reaction, the regenerated gas was fed. As in the reaction, a ceramic tube furnace was used for heating, and the temperature of the catalyst (mold) layer was controlled.

The playback conditions were set as follows.
Catalyst temperature: 490-600 ° C.
Processing time: 21 hours.
Regenerated gas: Air 10-40 Nml / min.

A total of four cycles of repeating the reaction and regeneration were performed.

Preparation Example 1
Atypical aluminosilicate gel was added to an aqueous solution of tetrapropylammonium (hereinafter sometimes abbreviated as TPA) hydroxide and sodium hydroxide and suspended. MFI-type zeolite was added as a seed crystal to the obtained suspension to prepare a raw material composition. The amount of the seed crystal added at that time was 0.7% by weight with respect to the weight _{of Al 2} O ₃ and SiO _{2 in the raw material composition.} In addition, the by-produced ethanol was removed by evaporation.

The composition of the raw material composition is as follows.
SiO ₂ / Al ₂ O ₃ molar ratio = 48, 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 with stirring at 115 ° C. to obtain a slurry-like mixture. The slurry-like mixture after crystallization was solid-liquid separated by a centrifugal sedimentation machine, and then the solid particles were washed with a sufficient amount of pure water and dried at 110 ° C. to obtain a dry powder.

The obtained dry powder was dispersed in hydrochloric acid at room temperature of 1 mol / L, filtered, and then the solid particles were washed with a sufficient amount of pure water, filtered again, and dried at 100 ° C. overnight. After firing at 550 ° C. for 1 hour under air, it was treated with 30% steam at 600 ° C. for 2 hours.

The obtained powder was dispersed in hydrochloric acid at room temperature of 1 mol / L, filtered, and then the solid particles were washed with a sufficient amount of pure water and filtered again to obtain zeolite. The obtained zeolite is an MFI-type zeolite which is a 10-membered ring-pore zeolite, and has a mesopore volume of 0.37 cc / g, a half-value width of 10 nm at the peak of the mesopore distribution, and a mesopore with a peak center value of 14 nm. It had a distribution. The macropore volume with a diameter of 0.2 to 200 μm was 0.10 cc / g.

To 100 parts by weight of the obtained zeolite, 25 parts by weight of silica (manufactured by Nissan Chemical Industries, Ltd., (trade name) Snowtex N-30G), 5 parts by weight of cellulose, and 40 parts by weight of pure water were added and kneaded. Then, the kneaded product was made into a columnar molded body having a diameter of 1.5 mm and a length of 1.0 to 7.0 mm (average length of 3.5 mm). This was dried at 100 ° C. overnight. The dried molded product was fired at 600 ° C. for 2 hours under air flow to obtain a molded product.

Example 1
Ion exchange was carried out by passing an aqueous silver nitrate solution through 5 g of the MFI-type zeolite molded product obtained in Preparation Example 1 at room temperature for 2 hours. As the silver nitrate aqueous solution used, 0.2 g of silver nitrate was dissolved in 25 ml of pure water. Then, pure water was passed to remove nitric acid produced as a by-product, and then the mixture was dried at 110 ° C. overnight and then calcined at 550 ° C. for 6 hours. A catalyst for producing an aromatic compound, which is a silver ion exchange molded product having a silver loading of 0.8 wt%, was obtained.

Ammonia TPD measurement of the catalyst for producing an aromatic compound obtained according to the above was carried out. The results are shown in Table 1. The amount of ammonia desorbed at 350 ° C. to 500 ° C. was 0.11 mmol / g, and the amount of ammonia desorbed at 500 ° C. to 750 ° C. was 0.026 mmol / g. The ratio of the amount of ammonia desorbed at 500 ° C. to 750 ° C. to the amount of ammonia desorbed at 350 ° C. to 500 ° C. calculated from both values was 24.1%.

Using the obtained catalyst for producing aromatic compounds, a water heat test was conducted under the above conditions to evaluate the water heat resistance. The results are shown in Table 1. It showed a high acid content maintenance rate even under the conditions of high temperature and high concentration of water vapor.

Then, using the obtained catalyst for producing an aromatic compound, an aromatic compound was produced under the above-mentioned conditions, and the aromatization was evaluated. Table 1 shows the conversion rate of C4 components and the yield of aromatic compounds after 3 hours and 22 hours in 1 to 4 cycles. It was confirmed that it showed a high C4 component conversion rate and aromatic yield, and maintained its high catalytic performance until the 4th cycle.

Example 2
A silver ion exchange molded product was obtained by the same operation as in Example 1 except that the amount of silver nitrate used in the silver nitrate aqueous solution was changed to 0.3 g with respect to 5 g of the MFI type zeolite molded product obtained in Preparation Example 1. , A catalyst for producing an aromatic compound, which is a silver ion exchange molded product having a silver carrying amount of 1.0 wt%, was obtained.

The above ammonia TPD measurement was carried out using the obtained catalyst for producing an aromatic compound. The results are shown in Table 1. The amount of ammonia desorbed at 350 ° C. to 500 ° C. was 0.11 mmol / g, and the amount of ammonia desorbed at 500 ° C. to 750 ° C. was 0.036 mmol / g. The ratio of the amount of ammonia desorbed at 500 ° C. to 750 ° C. to the amount of ammonia desorbed at 350 ° C. to 500 ° C. calculated from both values was 33.4%.

Using the obtained catalyst for producing aromatic compounds, a water heat test was conducted under the above conditions to evaluate the water heat resistance. The results are shown in Table 1. It showed a high acid content maintenance rate even under the conditions of high temperature and high concentration of water vapor.

Then, using the obtained catalyst for producing an aromatic compound, an aromatic compound was produced under the above-mentioned conditions, and the aromatization was evaluated. Table 1 shows the conversion rate of C4 components and the yield of aromatic compounds after 3 hours and 22 hours in 1 to 4 cycles. It was confirmed that it showed a high C4 component conversion rate and aromatic yield, and maintained its high catalytic performance until the 4th cycle.

Example 3
A silver ion exchange molded product was obtained by the same operation as in Example 1 except that the amount of silver nitrate used in the silver nitrate aqueous solution was changed to 0.5 g with respect to 5 g of the MFI type zeolite molded product obtained in Preparation Example 1. , A catalyst for producing an aromatic compound, which is a silver ion exchange molded product having a silver carrying amount of 1.2 wt%, was obtained.

The above ammonia TPD measurement was carried out using the obtained catalyst for producing an aromatic compound. The results are shown in Table 1. The amount of ammonia desorbed at 350 ° C. to 500 ° C. was 0.092 mmol / g, and the amount of ammonia desorbed at 500 ° C. to 750 ° C. was 0.026 mmol / g. The ratio of the amount of ammonia desorbed at 500 ° C. to 750 ° C. to the amount of ammonia desorbed at 350 ° C. to 500 ° C. calculated from both values was 28.3%.

Using the obtained catalyst for producing aromatic compounds, a water heat test was conducted under the above conditions to evaluate the water heat resistance. The results are shown in Table 1. It showed a high acid content maintenance rate even under the conditions of high temperature and high concentration of water vapor.

Then, using a catalyst for producing an aromatic compound, an aromatic compound was produced under the above-mentioned conditions, and the aromatization was evaluated. Table 1 shows the conversion rate of C4 components and the yield of aromatic compounds after 3 hours and 22 hours in 1 to 4 cycles. It was confirmed that it showed a high C4 component conversion rate and aromatic yield, and maintained its high catalytic performance until the 4th cycle.

Comparative Example 1
The above ammonia TPD measurement was carried out using the MFI type zeolite molded product obtained in Preparation Example 1. The results are shown in Table 1. The amount of ammonia desorbed at 350 ° C. to 500 ° C. was 0.14 mmol / g, and the amount of ammonia desorbed at 500 ° C. to 750 ° C. was 0.027 mmol / g. The ratio of the amount of ammonia desorbed at 500 ° C. to 750 ° C. to the amount of ammonia desorbed at 350 ° C. to 500 ° C. calculated from both values was 19.2%.

A water heat test was conducted under the above conditions to evaluate the water heat resistance. The results are shown in Table 1. It was confirmed that the acid content maintenance rate was significantly reduced and the heat resistance and water heat resistance were low.

Further, using the obtained molded product, an aromatic compound was produced under the above-mentioned conditions, and the aromatization was evaluated. Table 1 shows the conversion rate of C4 components and the yield of aromatic hydrocarbons after 3 hours and 22 hours in 1 to 4 cycles. It was confirmed that the conversion rate of C4 components and the yield of aromatics were low and the catalytic performance was inferior.

Comparative Example 2
Using 3 g of the MFI-type zeolite molded product obtained in Preparation Example 1, the silver nitrate aqueous solution was impregnated at room temperature for 10 minutes. The silver nitrate aqueous solution used was prepared with 0.2 g of silver nitrate and 2 ml of pure water. After impregnation, the mixture was dried at 110 ° C. overnight and then calcined at 550 ° C. for 6 hours. The amount of silver supported by the obtained silver ion exchange molded product was 3.0 wt%.

The above ammonia TPD measurement was carried out using the obtained silver ion exchange molded product. The results are shown in Table 1. The amount of ammonia desorbed at 350 ° C. to 500 ° C. was 0.19 mmol / g, and the amount of ammonia desorbed at 500 ° C. to 750 ° C. was 0.13 mmol / g. The ratio of the amount of ammonia desorbed at 500 ° C. to 750 ° C. to the amount of ammonia desorbed at 350 ° C. to 500 ° C. calculated from both values was 71.3%.

Using the obtained silver ion exchange molded product, a hydrothermal test and an evaluation of aromatization were performed under the above conditions. The results are shown in Table 1. Although the acid content maintenance rate was high, it was confirmed that the reaction results deteriorated from 1 cycle to 4 cycles and the catalytic performance was inferior.

Comparative Example 3
Ion exchange was carried out with 0.1 g of silver nitrate and 25 ml of pure water with respect to 10 g of the MFI type zeolite molded product obtained in Preparation Example 1. After removing the by-product nitric acid, it was dried at 110 ° C. overnight and then calcined at 450 ° C. for 2 hours. The amount of silver supported by the obtained silver ion exchange molded product was 1.2 wt%.

The above ammonia TPD measurement was carried out using the obtained silver ion exchange molded product. The results are shown in Table 1. The amount of ammonia desorbed at 350 ° C. to 500 ° C. was 0.12 mmol / g, and the amount of ammonia desorbed at 500 ° C. to 750 ° C. was 0.069 mmol / g. The ratio of the amount of ammonia desorbed at 500 ° C. to 750 ° C. to the amount of ammonia desorbed at 350 ° C. to 500 ° C. calculated from both values was 55.1%.

Using the obtained silver ion exchange molded product, a hydrothermal test and an evaluation of aromatization were performed under the above conditions. The results are shown in Table 1. Although the acid content maintenance rate was high, it was confirmed that the reaction results deteriorated from 1 cycle to 4 cycles and the catalytic performance was inferior.

Comparative Example 4
Ion exchange was carried out with 0.1 g of silver nitrate and 25 ml of pure water with respect to 5 g of the MFI type zeolite molded product obtained in Preparation Example 1. After removing the by-product nitric acid, it was dried at 110 ° C. overnight and then calcined at 550 ° C. for 6 hours. The amount of silver supported by the obtained silver ion exchange molded product was 0.6 wt%.

The above ammonia TPD measurement was carried out using the obtained silver ion exchange molded product. The results are shown in Table 1. The amount of ammonia desorbed at 350 ° C. to 500 ° C. was 0.11 mmol / g, and the amount of ammonia desorbed at 500 ° C. to 750 ° C. was 0.014 mmol / g. The ratio of the amount of ammonia desorbed at 500 ° C. to 750 ° C. to the amount of ammonia desorbed at 350 ° C. to 500 ° C. calculated from both values was 12.9%.

Using the obtained silver ion exchange molded product, a hydrothermal test and an evaluation of aromatization were performed under the above conditions. The results are shown in Table 1. Although the acid content maintenance rate was high, it was confirmed that the reaction results deteriorated from 1 cycle to 4 cycles and the catalytic performance was inferior.

The highly silver-dispersed aromatic compound production catalyst of the present invention has high heat resistance and water heat resistance, and at the same time has high productivity, and therefore has extremely high industrial value as a catalyst. ..

Claims (6)

A molded body containing 10-membered ring-pore zeolite and a binder, supporting silver as an active metal, and desorbing ammonia at 500 to 750 ° C. with respect to the amount of ammonia desorbed at 350 to 500 ° C. in the ammonia adsorption heated desorption analysis. A catalyst for producing an aromatic compound, wherein the ratio of the amount is 15 wt% to 50 wt%. The 10-membered ring-pore zeolite is a 10-membered ring-pore zeolite having mesopores satisfying the following characteristics (i) to (ii) and macropores satisfying the following characteristics (iii). The catalyst for producing an aromatic compound according to claim 1.
(I) The mesopore volume is 0.05 cc / g or more.
(Ii) The mesopores show a distribution having a peak, the full width at half maximum (hw) of the peak is hw ≦ 40 nm, and the center value (μ) of the peak is 5 nm ≦ μ ≦ 30 nm.
(Iii) The macropore volume of the macropores in the range of 0.2 to 200 μm in diameter is 0.03 cc / g or more and 0.30 cc / g or less. The catalyst for producing an aromatic compound according to claim 1 or 2, wherein the 10-membered ring-pore zeolite is an MFI-type zeolite or a MEL-type zeolite. The catalyst for producing an aromatic compound according to any one of claims 1 to 3, wherein the 10-membered ring-pore zeolite is a 10-membered ring-pore zeolite that has been calcined in a water vapor atmosphere. The catalyst for producing an aromatic compound according to any one of claims 1 to 4, wherein the binder is silica. An aromatic characterized by contacting a hydrocarbon having 4 to 6 carbon atoms in a temperature range of 500 to 650 ° C. in the presence of the catalyst for producing an aromatic compound according to any one of claims 1 to 5. Method for producing a compound.