JPH1052646A - High silica-zeolite type catalyst - Google Patents

Abstract

PROBLEM TO BE SOLVED: To have good coking resistance and regeneration deterioration resistance by a method in which the SiO2 /Al2 O3 mole ratio of zeolite, the particle size of primary particles, and the ratio of a surface melting point to the total melting point in a H-type are made specified values, after steam treatment in specified conditions, the amount of separated pyridine in the previous H-type meets an equation. SOLUTION: The mole ratio SiO2 /Al2 O3 of zeolite which constitutes a zeolite catalyst is made 20-200, and the particle size of primary zeolite particles is made 0.3-3μm. The ratio of a surface melting point to the total melting point when the zeolite catalyst is an H-type is made 0.03 0.15. Moreover, the quantity B of separated pyridine at 500-900 deg.C by a temperature increasing separation method, when the zeolite catalyst, after being treated with steam for 5hr at a partial pressure of 0.8atm and at 650 deg.C, is the H-type and the quantity A of separated pyridine at 500-900 deg.C by the temperature increasing separation method, when the catalyst is the H-type before steam treatment are made to meet an equation (αexpresses a parameter).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high silica zeolite catalyst used for a reaction containing an aromatic hydrocarbon in a raw material or a product. More specifically, the amount of carbonaceous material accumulated on the catalyst during a reaction containing an aromatic hydrocarbon in a raw material or a product is reduced, and a temporary decrease in activity due to the carbonaceous material is suppressed, Furthermore, high silica zeolite excellent in coking resistance and regenerative deterioration resistance, which suppresses permanent activity deterioration due to dealumination in a high temperature atmosphere in which water is present, such as occurs when the carbonaceous material is burned and removed with an oxygen-containing inert gas. It relates to a system catalyst.

[0002]

2. Description of the Related Art A method of synthesizing a zeolite having a high silica content and a high silica zeolite produced by the method have been known. For example, Japanese Patent Publication No. 46-10
No. 064 and JP-B-56-49850 disclose a method of hydrothermally treating a reaction mixture containing silica, alumina, an alkali metal, water and a supply material of an organic nitrogen cation precursor.

[0003] Further, a method for producing a high heat-resistant water-based high silica zeolite and a high silica zeolite produced by the method are also known. For example, Japanese Patent Application Laid-Open No. 7-2916
No. 20 discloses that a long-axis aluminosilicate gel having a pH of 11 to 13 obtained by simultaneously injecting a silica component and an alumina component into an aqueous solution of a neutral salt at 7.5 mol times or more per alumina component is used. A crystal containing 75% by number or more of long hexagonal plate-like crystal particles having a ratio of a short axis to a short axis of 2 to 15 and a ratio of a long axis to a thickness of 4 to 50 and subjected to a steaming treatment at 900 ° C. for 5 hours. A high silica zeolite having a retention of 85% or more and having a higher ion exchange rate than conventional high silica zeolite and excellent hot water resistance, and a method for producing the same are disclosed.

[0004] Further, Japanese Patent Application Laid-Open No. Hei 3-293030 discloses that
Expressed in molar composition of _{oxides, aK 2 O, bNa 2 O} , A
1. A highly heat-resistant zeolite which is l ₂ O ₃ , cSiO ₂ , dH ₂ O, and which is under water vapor containing 10% or more of water, 900
It discloses a highly heat-resistant zeolite having a crystallinity of 90% or more before hot-water treatment at 5 ° C. for 5 hours and a method for producing the same.

[0005] Also, Japanese Patent Application Laid-Open No. 3-193622 discloses that
When a raw material mixture containing a silica source, an alumina source, an alkali metal source, and water is crystallized under hydrothermal synthesis conditions, as a seed slurry, an X-ray diffraction pattern of a solid in the slurry after drying is ZSM-5. Yes, nitrogen adsorption BET surface area is 10
It discloses a method for producing ZSM-5 fine particles, which comprises adding a hydrothermal slurry during crystallization of 0 to 250 m ³ / g before crystallization of 10 to 40% by weight of the whole.

Further, Japanese Patent Publication No. 7-35343 and Japanese Patent Publication No. 7-94396 disclose ZS containing zinc.
In a method for producing an aromatic hydrocarbon from a light hydrocarbon using an M-5 type zeolite as a catalyst, the catalyst has a specific silicon / aluminum atomic ratio and a zinc / silicon atomic ratio, The ZS in ° C
The amount of pyridine released per gram of M-5 zeolite is 4
A method for producing an aromatic hydrocarbon, which is characterized in that the amount is 0 to 120 μmol, is disclosed.

However, the high silica zeolite synthesized by the method described in JP-B-46-10064 or JP-B-56-49850 has insufficient crystallinity and poor heat resistance of the crystal itself. There is a problem that the zeolite catalyst is permanently deteriorated due to dealumination in a high temperature atmosphere where water is present, as occurs when burning and removing carbonaceous matter accumulated during the reaction. Since the amount of carbonaceous matter is large, there is a problem that a facility for burning and removing the carbonaceous matter becomes large.

[0008] JP-A-7-291620 and JP-A-Hei 3
Although the zeolite synthesized by the method of Japanese Patent No. 293031 is a zeolite having high hot water resistance, its use in a reaction system containing an aromatic hydrocarbon in a raw material or a product is not described. The problem of activity reduction due to carbonaceous material accumulated on the zeolite catalyst was not recognized per se.

In general, zeolites having high hot water resistance must have a high degree of crystallinity, so that the particle size tends to increase as a result. Since the ratio to the point is small, in a reaction containing an aromatic hydrocarbon in the raw material or the product, there is a problem that the activity decreases rapidly due to the carbonaceous material accumulated on the zeolite catalyst during the reaction, and the reaction is not practical. .

The zeolite synthesized in JP-A-3-193622 is a fine-particle zeolite used in a reaction for producing cyclohexanol from cyclohexene, as described in the examples, and has a particle size of The purpose is to extend the catalyst life due to carbonaceous accumulation by atomization.

The zeolite of the present application is disclosed in, for example,
It is also possible to synthesize by the method of 193622, but if the particle size of the zeolite synthesized by that method is too small, or if the ratio of surface acid sites to all acid sites is too large,
In a reaction containing a component, such as olefin or aromatic hydrocarbon, particularly styrene, which causes an increase in carbonaceous matter accumulated during the reaction in the raw material or product, the amount of carbonaceous matter accumulated during the reaction Increase.

[0012] When the amount of carbonaceous material is increased, if the equipment for burning and removing the same is the same, the time for burning and removing is longer than when the amount of carbonaceous matter is small. However, there is a problem in that the equipment for burning and removing becomes large, the amount of water generated per unit time increases, and the permanent deterioration due to dealumination is fast.

The ZSM-5 described in Examples of JP-A-3-193622 has a low degree of crystallinity and has a low water content such as occurs when burning off carbonaceous matter accumulated during the reaction. There is a problem that the zeolite catalyst is permanently deteriorated by dealumination in a high-temperature atmosphere in which zeolites exist.

In Japanese Patent Publication No. 7-35343 and Japanese Patent Publication No. 7-94396, in a method for producing an aromatic hydrocarbon from a light hydrocarbon, a decrease in activity over time due to carbonaceous matter accumulated during the reaction is reduced. Therefore, it is a catalyst having a specific silicon / aluminum atomic ratio and a zinc / silicon atomic ratio, and the desorption amount of pyridine per 1 g of ZSM-5 type zeolite at 500 to 900 ° C. by a temperature-programmed desorption method is 40 to 120 μmol. Discloses a production method using a catalyst containing a ZSM-5 type zeolite. By keeping the amount of pyridine desorbed within the above range, the activity required for producing aromatic hydrocarbons from light hydrocarbons is maintained, and a decrease in activity over time due to accumulated carbonaceous materials is reduced.

[0015] However, in these publications, as occurs when burning and removing carbonaceous matter accumulated during the reaction,
The problem of permanent deterioration of the zeolite catalyst due to dealumination in a high-temperature atmosphere containing water has not been solved. As is evident from the examples in both publications, the catalyst was prepared at a partial pressure of H ₂ O of 0.8 atm at 650 ° C.
The amount of pyridine desorbed (B) at 500 to 900 ° C. by the thermal desorption method when converted to H-type after steaming for a period of time and the temperature-programmed desorption when converted to H-type before the steaming Α, which is expressed by the amount of pyridine desorbed at 500 to 900 ° C. by the method (A), is larger than 1.6,
Deterioration due to precipitation of carbonaceous material in each reaction is small, but permanent deterioration is fast, and it is practical for repeated use and regeneration for burning and removing carbonaceous material accumulated during the reaction for several months or years. I can't stand it.

As enumerated above, various methods for synthesizing zeolites have been proposed as described above, but in a reaction in which an aromatic hydrocarbon is contained in a raw material or a product, a catalyst is formed on the catalyst during the reaction. The amount of accumulated carbonaceous material is small, and
It is possible to suppress a temporary decrease in activity due to the carbonaceous material, and further to suppress a permanent activity deterioration due to dealumination in a high-temperature atmosphere where water is present, which occurs when the carbonaceous material is burned and removed with an oxygen-containing inert gas. No high silica zeolite-based catalyst which has both excellent coking resistance and regenerative deterioration resistance has not been found.

[0017]

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a high silica zeolite-based catalyst used for a reaction in which an aromatic hydrocarbon is contained in a raw material or a product. Reducing the amount of carbonaceous material that accumulates on the catalyst during the reaction and suppressing a temporary decrease in activity due to the carbonaceous material; and furthermore, when burning off the carbonaceous material with an oxygen-containing inert gas. It is an object of the present invention to provide a high silica zeolite catalyst excellent in coking resistance and regenerative deterioration resistance, which can suppress permanent activity deterioration due to dealumination in a high temperature atmosphere where moisture is present.

[0018]

As a result of intensive studies, the present inventor has found that a specific SiO ₂ / Al ₂ O ₃ is used as a high silica zeolite used in a reaction in which an aromatic hydrocarbon is contained in a raw material or a product. The inventors have found that the use of zeolite having a molar ratio, a specific particle diameter, a specific acid site ratio, and a specific acid site can solve the above-mentioned problems at once, and completed the present invention.

That is, the present invention relates to a high silica zeolite-based catalyst used for a reaction in which a raw material or a product contains an aromatic hydrocarbon, and the following requirements (1), (2),
An object of the present invention is to provide a high silica zeolite catalyst satisfying (3) and (4). (1) Si of zeolite constituting the zeolite catalyst
O ₂ / Al ₂ O ₃ molar ratio of 20 to 200. (2) The primary particles of the zeolite constituting the zeolite catalyst have a particle size of 0.3 to 3 μm. (3) The ratio of surface acid sites to all acid sites when the zeolite-based catalyst is H-type is 0.03 to 0.15. (4) The zeolite-based catalyst is treated with a H ₂ O partial pressure of 0.8 atm,
After steam treatment at 650 ° C. for 5 hours, the amount of pyridine desorbed (B) at 500 to 900 ° C. by the temperature-programmed desorption method when the H-form was formed and the H-form before the steam treatment The pyridine desorption amount (A) at 500 to 900 ° C. by the thermal desorption method satisfies the following.

[0020]

(Equation 2)

In the present invention, the reaction in which an aromatic hydrocarbon is contained in a raw material or a product is defined as 5% in the raw material of the reaction.
By weight or more aromatic hydrocarbons, or
A reaction in which the product of the reaction contains 5% by weight or more of an aromatic hydrocarbon. When an aromatic hydrocarbon, particularly an aromatic hydrocarbon having 8 or more carbon atoms, such as styrene, is contained in a raw material or a product, much carbonaceous material accumulates during the reaction. Examples of the reaction in which an aromatic hydrocarbon is contained in a raw material or a product include a cyclization reaction for producing an aromatic hydrocarbon from a light hydrocarbon containing olefin and / or paraffin, and a hydrocarbon such as naphtha or H-NGL. Efficiently convert lower olefins and aromatic hydrocarbons from raw materials containing
And a catalytic cracking reaction for obtaining a lower olefin containing ethylene as a main component at a higher yield than an aromatic hydrocarbon, a disproportionation reaction of toluene, an isomerization reaction of xylene, and an ethylbenzene synthesis reaction.

Hereinafter, among these reactions, a cyclization reaction for producing an aromatic hydrocarbon from a light hydrocarbon containing olefin and / or paraffin will be described in detail. The light hydrocarbon containing olefin and / or paraffin in the present invention is a hydrocarbon having 2 or more carbon atoms and a 90% distillation temperature of 190 ° C. or less. For example, paraffin is ethane, propane, butane, pentane, hexane, heptane, octane, nonane, and olefin is ethylene, propylene, butene, pentene,
Hexene, heptene, octene and nonene are listed.
In addition to the above, naphthane and naphthene such as cyclopentane, cyclopentene, methylcyclopentane, cyclohexane, methylcyclopentene, cyclohexene and cyclohexadiene may be contained, and dienes such as butadiene, pentadiene and cyclopentadiene may be contained.

Each of the above mixtures may be used as a raw material, and the mixture may contain N ₂ , CO ₂ , C
H ₂ , CH ₄ to suppress the generation of inert gas such as O and carbonaceous material (coke) accumulated on the catalyst during the reaction.
May be included. It is particularly preferable that the weight ratio of the saturated hydrocarbon to the unsaturated hydrocarbon in the mixture is from 0.43 to 2.33. Here, the weight ratio of the saturated hydrocarbon to the unsaturated hydrocarbon means the weight ratio in the supplied mixture.

The mixture may be a mixture of each of the above, or a C ₄ fraction of a high-temperature pyrolysis product of petroleum hydrocarbon such as naphtha, or a fraction obtained by removing butadiene or butadiene and i-butene from the C ₄ fraction. min, C ₅ fraction of a high temperature pyrolysis product, the C ₅ fraction obtained by removing dienes from the fraction, raffinate been pyrolysis gasoline, aromatic hydrocarbons extracted from pyrolysis gasoline, FCC-LPG, FCC
Cracked gasoline, a raffinate obtained by extracting aromatic hydrocarbons from reformate, coker of LPG, but straight-run naphtha and the like, Of these, C ₄ fraction of hot pyrolysis product of a petroleum hydrocarbon such as naphtha, C ₅ fractions, C ₄ , C ₅
Butadiene from fraction, i- butene, isoprene fraction excluding part or all of the cyclopentadiene are available particularly preferably, the C ₄ fraction, the weight ratio of the C ₅ fraction 3/7
Raw materials that are ~ 7/3 are particularly preferred. Here, the weight ratio of the C ₄ fraction and the C ₅ fraction means the weight ratio in the supplied mixture. In the method of the present invention, the raw material may contain oxygen-containing compounds such as TBA and methanol as impurities.

The zeolite constituting the high silica zeolite catalyst in the present invention is the zeolite having a SiO ₂ /
Al ₂ O ₃ molar ratio is 20 to 200, for example, β-
Zeolite, Ω-zeolite, Y-zeolite, L-zeolite, erionite, offretite, mordenite, ferrierite, ZSM-5, ZSM-8, ZSM
-11, ZSM-12, ZSM-35, ZSM-38, etc., but ZSM-5, ZSM-8, ZSM-1
Crystalline aluminosilicates or metallosilicates of the ZSM-5 type such as 1 are preferred. For the zeolite of ZSM-5, for example, U.S. Pat. No. 5,268,162 can be referred to.

All zeolites used in the present invention are H
It can be used as a metal or metal substitution type, and the metal of the metal substitution type is preferably a metal belonging to Group VIII, Ib, IIb, or IIIb. VII
As a metal belonging to Group I, Group Ib, Group IIb, Group IIIb, Zn, Cu, Ag, Ni, Pt, Pd, and Ga are more preferable, and among them, Zn, Ag, Ni, and Ga are preferable.
Is more preferably used. At this time, the metal may be contained in the zeolite framework or may be ion-exchanged. Further, as described later, a binder such as alumina and / or a metal oxide such as zinc oxide which promotes dehydrogenation can be used in combination.

In the present invention, the method of synthesizing the zeolite is not particularly limited, but the method of synthesizing using a seed slurry described in JP-A-3-193622 is particularly preferable. Further, in the method of the present invention, as described in International Application No. PCT / JP95 / 02040, SiO
In ₂ / Al ₂ O ₃ molar ratio of 20 or more, having a metal belonging to one or more of the periodic table Group Ib, may also be used an intermediate pore size zeolite substantially free of protons. In any case, the molar ratio of SiO ₂ / Al ₂ O ₃ , the particle size of the primary particles of the zeolite, the ratio of the surface acid sites to the total acid sites when the zeolite is H-type, and the parameter α are within the range of the present invention. is important.

The SiO ₂ / Al ₂ O ₃ molar ratio of the feed, stirring speed, the synthesis conditions such as synthesis temperature, whether the use of templates, by adjusting the type of the template used, SiO ₂ / Al ₂ O zeolite _{The 3} molar ratio, the particle size of the primary particles of the zeolite, the ratio of the surface acid sites to the total acid sites when the zeolite is H-shaped, and the parameter α can be set within the scope of the present invention.

The zeolite constituting the catalyst of the present invention is S
the iO ₂ / Al ₂ O ₃ molar ratio is from 20 to 200;
0 to 100 is preferable, and 30 to 80 is more preferable. When the SiO ₂ / Al ₂ O ₃ molar ratio is less than 20,
Permanent removal by dealumination in a high-temperature atmosphere with moisture, such as occurs when burning off carbonaceous material that accumulates on the catalyst during the reaction in which the raw material or product contains aromatic hydrocarbons with an oxygen-containing inert gas Activity degradation is faster.

The permanent activity deterioration due to dealumination is X
It is considered that the higher the relative value of the crystallinity by the X-ray diffraction method, the more the crystallinity is suppressed, but the relative value of the crystallinity is SiO ₂ / Al
Is affected by the ₂ O ₃ molar ratio, the SiO ₂ / Al ₂ O ₃ molar ratio is less than 20, or a greater than 200, the relative value of the crystallinity is reduced, fast permanent degradation due to dealumination, undesirable . In addition, SiO ₂ / Al ₂
If the O ₃ molar ratio is more than 200, sufficient activity cannot be obtained, and the catalyst may not have sufficient activity for the reaction in which the raw material or the product contains an aromatic hydrocarbon.

The zeolite constituting the catalyst of the present invention, Si
The O ₂ / Al ₂ O ₃ molar ratio refers to a hydrothermally synthesized zeolite that does not contain alumina or silica as a binder and that is capable of removing aluminum, such as steam treatment, or converting aromatic hydrocarbons from light hydrocarbons. Fresh zeolite which has not been subjected to a reaction such as formation is converted to a fluorescent X-ray apparatus or an EPM.
It is a molar ratio determined by measuring with A (X-ray macro analyzer).

As the zeolite-based catalyst in the present invention, those consisting essentially of the above-mentioned H-type or metal-substituted zeolite can be used, and the above-mentioned zeolite, the group VIII, the group Ib, At least one metal selected from metals belonging to Group IIb and IIIb and a mixture thereof with at least one selected from the group consisting of compounds thereof (for example, metal oxides promoting dehydrogenation such as zinc oxide). Or those carried as a compound are preferred.

Group VIII, Ib, IIb, IIIb
The metals belonging to the group include Zn, Cu, Ag, Ni, P
t, Pd, and Ga are more preferable, and among them, Z
n, Ag, Ni, and Ga are more preferably used. For example, it is preferable to include a mixture of zeolite and at least one selected from zinc and a compound thereof. Furthermore, when alumina and silica are used together as a binder,
More preferred.

In the present invention, the zinc component includes, for example, zinc, zinc oxide, zinc hydroxide, or a salt such as zinc nitrate, zinc carbonate, zinc sulfate, zinc chloride, zinc acetate, zinc oxalate, or an alkyl zinc. Organic zinc compounds may be mentioned.

In the present invention, the zeolite-based catalyst is
It preferably contains a mixture of zeolite, a zinc component, and alumina. It is also preferred that the mixture of a zeolite and a mixture obtained by heat-treating a mixture of a zinc component and alumina in steam. In both catalysts, when steam treatment is applied, the zinc component reacts with alumina to convert to zinc aluminate, which stabilizes zinc and produces aromatic hydrocarbons from light hydrocarbons containing olefins and / or paraffins in high yield. In the reaction or the like, the scattering loss of zinc can be greatly reduced. The term "zinc aluminate" as used herein means JCPDS 5-0669NBS Cir when observed with an X-ray diffractometer such as XD-610 manufactured by Shimadzu Corporation.
c. , 539, Vol. II, 38 (1953) having the same X-ray diffraction pattern as that shown in FIG.

As an alumina source of alumina, anhydrous alumina or hydrated alumina is used. In addition, for example, anhydrous alumina or hydrated alumina is produced by hydrolysis, thermal decomposition, oxidation or the like like an aluminum salt. Raw materials that can be used can also be used.

In the present invention, it is also preferable to use an alumina sol as the alumina source. When an alumina sol is used as the alumina source, the zinc component reacts with the alumina to produce zinc aluminate without performing the steam treatment, so that zinc is stabilized.

In the above-mentioned zeolite-based catalyst, the content of at least one selected from zinc and its compound is preferably 5 to 25% by weight as zinc. In the present invention, the alumina content of the case containing alumina, 5-50 wt% relative to the total catalyst as Al ₂ O _3, preferably 15 to 40 wt%, and, when containing alumina and zinc, alumina And the molar ratio of zinc (Al
₂ O ₃ / Zn) is 1 or more.

In the present invention, it is preferable that zinc oxide and zinc aluminate coexist in the zeolite catalyst at the time of the reaction. Since zinc aluminate has a spinel structure, the scattering of zinc from the zeolite-based catalyst is suppressed, but the effect of improving the aromatic selectivity, which is the original purpose of supporting zinc, is reduced.
It is preferable that zinc oxide exhibiting an effect of improving the aromatic selectivity is coexisted. The preferred amount of zinc oxide and zinc aluminate is from 1.2 to 20 zinc oxide at the time when the raw material or product is subjected to a reaction containing an aromatic hydrocarbon.
%, Zinc aluminate 8.2 to 50% by weight, more preferably zinc oxide 1.0 to 5.0% by weight and zinc aluminate 14 to 40% by weight.

Although the effect of improving the aromatic selectivity of zinc aluminate itself is small, it serves as a supply source of zinc oxide and suppresses the decrease of zinc oxide. As a result, the effect of improving the aromatic selectivity can be maintained for a long time. . Further, the presence of zinc aluminate also has an effect of suppressing the scattering speed of the zinc oxide due to reduction during a reaction in which a raw material or a product contains an aromatic hydrocarbon. Therefore, the coexistence of zinc aluminate with zinc oxide in the catalyst is effective for maintaining the aromatic selectivity improving effect.

The zinc oxide referred to in the present invention is one measured by the following analysis method. That is, 1 g of the catalyst is ground in a mortar to about several hundred microns, dried at 120 ° C. for 1 hour, accurately weighed out about 0.5 g, and put into a 200 cc beaker. 150 cc of a 3% hydrochloric acid aqueous solution is added thereto, and the mixture is heated at 80 ° C. for 2 hours on an electric heater. Thereafter, the solution was filtered through a 0.2 μm membrane filter, and the filtrate was analyzed by an atomic absorption spectrometer (Shimadzu Seismic Atomic Absorption / Frame Spectrophotometer AA).
-640-12 type), and perform quantitative analysis of zinc oxide by the standard addition method.

The weight of zinc aluminate in the present invention is obtained by subtracting the weight of zinc oxide quantitatively analyzed by the above method from the total weight of zinc. The term “total zinc weight” as used herein refers to the value obtained from a calibration curve of a standard substance using a fluorescent X-ray analyzer (Rigaku RIX1000).

The particle size of the primary particles of the zeolite in the present invention, as in the case of the SiO ₂ / Al ₂ O ₃ molar ratio, refers to the size of the primary particles when the zeolite in a substantially fresh state is observed with a scanning electron microscope. The particle size. In the present invention, the particle diameter is 0.1.
It is preferably from 3 to 3 μm, more preferably from 0.5 to 2 μm. There are various shapes of these primary particles, and the particle size mentioned here indicates the average diameter of the widest part of each particle. These primary particles may exist alone or may be secondary aggregated.

If the particle size is smaller than 0.3 μm, the amount of carbonaceous material accumulated on the catalyst during the reaction in which the raw material or product contains an aromatic hydrocarbon increases, and the carbonaceous material contains oxygen. As in the case of burning and removing with inert gas, permanent activity degradation due to dealumination in a high temperature atmosphere where moisture is present is accelerated. Conversely, if the particle size is larger than 3 μm, the raw material or product contains aromatic hydrocarbons The carbonaceous material that accumulates on the catalyst during the reaction causes a temporary decrease in activity, which is not practical.

In the present invention, at the time when the zeolite-based catalyst is subjected to the reaction, the ratio of the surface acid sites to the total acid sites in the H-form is 0.03 to 0.15,
0.05 to 0.1 is more preferred. If the ratio of surface acid sites to total acid sites is less than 0.03, a temporary decrease in activity due to charcoal light accumulating on the catalyst during the reaction in which the raw material or product contains aromatic hydrocarbons will occur. Conversely, if the ratio is greater than 0.15, the amount of light coal accumulated on the catalyst during the reaction in which the raw material or product contains aromatic hydrocarbons increases, and the carbonaceous material becomes oxygen-free. The permanent activity degradation due to dealumination in a high temperature atmosphere where water is present, such as occurs when burning and removing with an inert gas containing, is accelerated.

In the present invention, the H ₂ O partial pressure of the catalyst is 0.8.
Atm, steam treatment at 650 ° C. for 5 hours is performed by filling the quartz reaction tube 10 of 10 mmφ in the order of quartz wool 11, catalyst 12, and Raschig ring 13 from below in the apparatus shown in FIG. The temperature of the catalyst 12 is 650
The quartz reaction tube 10 is heated in an electric furnace 16 whose temperature can be adjusted with a thermocouple 15 for temperature adjustment so as to have an isothermal temperature of 0 ° C., and is substantially fresh at atmospheric pressure and a partial pressure of H ₂ O of 0.8 atm. This is carried out by supplying water or steam to the appropriate catalyst from the raw material inlet 17 for 5 hours.

In the present invention, the catalyst is subjected to steam treatment at 650 ° C. for 5 hours at a partial pressure of H ₂ O of 0.8 atm according to the above-mentioned method, followed by heating and desorption when the catalyst is converted to H-form.
Desorption amount (B) of pyridine at 00 to 900 ° C. and 500
The following parameter α represented by the pyridine desorption amount (A) at -900 ° C. is 1.6 or less, particularly preferably 1.4 or less.

[0048]

(Equation 3)

If the parameter α is greater than 1.6, the carbonaceous material that accumulates on the catalyst during the reaction in which the raw material or the product contains aromatic hydrocarbons, such as occurs when burning off carbonaceous material with an oxygen-containing inert gas. In a high temperature atmosphere, the permanent activity degradation due to dealumination is fast, and the regeneration deterioration resistance is poor.

The parameter α depends on the crystallinity determined by the X-ray diffraction method. That is, as shown in Comparative Examples described later, and when the particle diameter of the zeolite as in Comparative Example 1 is small, if the SiO ₂ / Al ₂ O ₃ molar ratio as in Comparative Example 3 is smaller, further comparative example SiO ₂ as 4 When the / Al ₂ O ₃ molar ratio is large, the relative value of the degree of crystallinity by the X-ray diffraction method is small, the parameter α is large, and the deterioration resistance to reproduction deteriorates.

Further, even when the SiO ₂ / Al ₂ O ₃ molar ratio and the particle size are within the ranges of the present invention, the parameter α becomes larger than 1.6 as in Comparative Example 5, and the deterioration resistance to reproduction deteriorates. In some cases. Also in Comparative Example 5, since the relative value of the degree of crystallinity is small, it is estimated that amorphous zeolite coexists in the synthesized zeolite. Therefore, in order to obtain a catalyst that has little permanent activity deterioration due to dealumination in a high-temperature atmosphere in the presence of moisture and can withstand several years of repeated reaction / regeneration, all of the requirements (1) to (4) of the present invention must be satisfied. Must meet. Here, the relative value of the degree of crystallinity refers to 2θ of the X-ray diffraction pattern of zeolite of the zeolite-based catalyst.
= 23.1 °, 24.0 °, 24.4 ° means the relative value of the sum of the peak heights.

The method of measuring the amount of desorption and the ratio of surface acid sites to all acid sites is as follows. (Method of Measuring Acid Point) First, before measuring the acid point, if the zeolite-based catalyst is not of H type, the following method is used.
Must be typed. To convert the zeolite to the H-form, 1N nitric acid was added to the zeolite to form a 10% by weight slurry, ion-exchanged at 60 ° C. for 4 hours, and the slurry was filtered and further washed with 5 times the amount of water. Then, it is dried at 120 ° C. for 10 hours. The acid point of the H-type zeolite thus obtained is measured by the following method.

As an acid point measuring device, a gas chromatography GC-14A and a data processing device CR-4A manufactured by Shimadzu Corporation were used. FIG. 1 shows an acid point measuring apparatus used in the present invention. That is, inner diameter 6 mm, total length 220 mm
Is filled with 0.1 to 1 g of the sample 4 in the short column 3 made of SUS. The sample 4 is 1 to 5 if it is formed into a pellet.
In the case of a powder having a length of 1 mm, the powder is compression molded into 20 to 30 mesh and filled. 60cc of nitrogen as carrier gas
Flow while adjusting the gas flow meter 1 at a flow rate of 1 / min, and at the same time, a tubular electric furnace 2 having a furnace core tube inner diameter of 20 mmφ and a length of 150 mm.
180 ° C. if the amine used is pyridine
In the case of 4-methylquinoline, the temperature is set to 280 ° C.
Next, a fixed amount (1 μcc) of the amine (pyridine, 4-methylquinoline) was transferred from the injection port 5 for a certain period (2 to 5) using an autosampler micro syringe (AOC).
Minutes) and continue intermittent infusion.

On the other hand, the carrier gas which has passed through the packed column 3 is analyzed by using the FID type detector 6 to obtain a chromatogram of a time-dependent change in amine concentration in which a peak periodically appears. As the number of injections increases, the amount of amine adsorbed on the sample approaches saturation, and accordingly, the amount of non-adsorbed amine obtained by injection increases. Therefore, in the chromatogram, the non-adsorption peak area S _i corresponding to the injection of the amine gradually approaches the area S _o corresponding to the amount of the injected amine.
That is, the peak area S confirmed by the data processing device
the total count number corresponding to the _i is, closer to the number of total count corresponding to the area S _o. If the total count number N _i corresponding to the non-adsorbed amine amount obtained, and the total count number N _i-1 corresponding to the non-adsorbed amount of amine obtained upon injection of the immediately preceding, the following conditions are met It is determined that the amine adsorption amount has become saturated.

[0055]

(Equation 4)

After it is determined under the above conditions that the saturated adsorption of the amine to the catalyst has been completed, the temperature is raised in the tubular electric furnace 2 at a rate of 15 ° C./min. Here, F around the amine injection port 5
Except for the portion inside the electric furnace, the gas flow path between the ID type detectors 6 is heated by a ribbon heater 8 or the like, and the outside is covered with a heat insulating material 9. 4-
In the case of methylquinoline, keep the temperature at 300 ° C. Temperature detection is performed at the position of the temperature detection end that is closely attached to the outside of the sample tube.
The amine desorbed from the sample 4 before the temperature detecting end 7 reaches 900 ° C. is detected by the FID type detector 6 and the desorbed amount is converted using the calibration curve of the amine.

In the present invention, the total acid point is represented by the amount of pyridine eliminated when pyridine is used as an amine, and the surface acid point is the 4-acid quinoline when measured using 4-methylquinoline as an amine. It is expressed as the amount of methylquinoline desorbed. The amount of pyridine desorbed at 500 to 900 ° C. by the temperature-programmed desorption method refers to the desorption amount obtained from the time when the temperature detecting end 7 reaches 500 ° C. until the temperature is further raised to 900 ° C. The separation. Each desorption amount is expressed as the desorption amount per g of the catalyst containing zeolite.

(Method of Measuring Primary Reaction Rate Constant of n-Hexane Decomposition) The primary reaction rate constant of n-hexane decomposition of the catalyst in the present invention is 10 mmφ using an apparatus shown in FIG.
The quartz reaction tube 10 is filled with quartz wool 11, a catalyst 12 substantially free of carbonaceous material (coke), and a Raschig ring 13 from the bottom in this order, and the temperature of the catalyst 12 measured by a thermometer 14 is 500 ° C. isothermally. Thermocouple for temperature control 1
The quartz reaction tube 10 is heated in an electric furnace 16 whose temperature can be adjusted at 5, and the atmospheric pressure, weight hourly space velocity (WHSV) 4 hr
^Under the condition of ^-1 , n-hexane was supplied from the raw material inlet 17, and the reaction product 0.75 to 1 hour after the supply of n-hexane was cooled in the condenser 18. After cooling with a dry ice / ethanol refrigerant, the oil components separated in the oil trap 19 and the gas components separated in the generated gas collecting bag 20 are all collected.

Then, a FID-TCD gas chromatography (HP-589) manufactured by Hewlett-Packard Company was used.
0 Series II), and substitute the gas composition in the reaction product obtained by analyzing the oil composition by FID gas chromatography (GC-17A) manufactured by Shimadzu Corporation into the following formula. Means the first-order rate constant of decomposition of n-hexane based on zeolite on the average of the above-mentioned gas / oil sampling time of 0.25 hours.

[0060]

(Equation 5)

The above first-order reaction rate constant is representative of the activity of the catalyst, and the first-order reaction rate constant for the decomposition of n-hexane of the zeolite catalyst in the present invention is 0 at the time of being subjected to the reaction. .2 or more,
0.3 or more is more preferable. A catalyst having a primary reaction rate constant of less than 0.2 for n-hexane decomposition has low activity, and the desired product obtained by a reaction in which a raw material or a product contains an aromatic hydrocarbon is reduced.

[0062]

Now, the present invention will be described in further detail with reference to Examples and Comparative Examples.

[0063]

【Example】

Example 1 An aqueous solution of sodium silicate (SiO ₂ : 26% by weight, Na ₂
O: 7.0% by weight) To 8.0 kg of NaOH 0.05 kg
The solution was added H ₂ O4kg _{and, Al 2 (SO 4) 3} ·
16H ₂ O0.61kg and 1,3 dimethylurea 0.1
A solution in which 15 kg of H ₂ O was dissolved was added with stirring, and 10 kg of 5% by weight sulfuric acid was added to obtain a homogeneous gel. This gel was charged into a 50-liter autoclave, and stirred with a stirring power of 0.5 to 1 KW / m ² for 16 hours.
A synthesis reaction was performed at 0 ° C. for 10 hours to obtain a seed slurry.

Next, Special No. 3 sodium silicate (Fuji Chemical Co., Ltd.)
(Manufactured by Sharp Corporation, SiO ₂ 25% by weight, Na ₂ O 8% by weight)
17.47 kg of H ₂ O and Al ₂ (S
O ₄ ) ₃ · 16H ₂ O (manufactured by Wako Pure Chemicals KK) 0.2
48 kg and sulfuric acid (purity 97, manufactured by Wako Pure Chemicals KK)
%) Of 0.353 kg, and 10.49 kg of the slurry obtained above as a seed slurry was added to obtain a homogeneous gel. This gel was placed in a 50 liter autoclave and crystallized at 150 ° C. for 45 hours while stirring at a rotation speed of 110 rpm.

After the obtained slurry was filtered, it was washed with 5 times the amount of water and dried at 120 ° C. for 5 hours. A scanning electron micrograph of the dried product is shown in FIG. As is clear from the drawing, the ZSM-5 produced has a widest part with a thickness of 1.5 to 2 μm and an average of 1.2 μm.

Subsequently, the obtained dried product was SiO ₂ / Al
_{When the 2} O ₃ molar ratio was measured using a fluorescent X-ray apparatus,
36. Further, the dried product is mixed with 1N nitric acid in 1N.
After ion exchange with a 0% by weight slurry at room temperature for 3 hours,
The mixture was filtered, washed with 5 volumes of water, and further dried at 120 ° C. for 10 hours.

144 g of zinc nitrate hexahydrate was dissolved in 400 g of water, 400 g of alumina sol (alumina sol 520 manufactured by Nissan Chemical Industries, Ltd.) and 200 g of the above H-ZSM-5 were added, and the mixture was heated and mixed at 50 ° C. for 2 hours. The above mixture, in which the water content is reduced and becomes clay, is 1.6 mm in diameter and 4 to 6 mm in length.
After being molded into a columnar shape, dried at 120 ° C. for 2 hours, and calcined in an electric furnace at 500 ° C. for 3 hours in an air atmosphere.
A H-ZSM-5 zeolite catalyst containing 5% by weight was formed.

Further, the obtained shaped catalyst was filled in a quartz reaction tube of the apparatus shown in FIG. 2 and was heated at 650 ° C. by the method described above.
The steam treatment was performed for 5 hours under the condition of a H ₂ O partial pressure of 0.8 atm. Next, the amount of pyridine desorbed at 500 to 900 ° C. by the temperature-programmed desorption method before and after the above-mentioned steam treatment when the H-type was formed was determined by the above method.

Subsequently, in order to make the catalyst and the catalysts of Examples and Comparative Examples described later have the same initial activity, 650 ° C.
An additional steam treatment was performed for 1.2 hours under the condition of a H ₂ O partial pressure of 0.8 atm. After the steam treatment, the first-order rate constant of n-hexane of the catalyst and the ratio of surface acid sites to total acid sites were determined by the method described above.

Next, in order to evaluate the regenerative degradation resistance of the catalyst, a model regenerative degradation test was performed. That is, the catalyst which had been subjected to the steam treatment for a total of 6.2 hours was used as the second catalyst.
Filled in the device shown in the figure, 530 ° C, H ₂ O partial pressure 0.15
Additional steam treatment was performed for 100 hours under the conditions of atm, and the first-order rate constant of n-hexane of the catalyst before and after the treatment was determined by the same method as described above. Table 1 shows the results.

Further, in order to evaluate the coking resistance,
The molded H-ZSM-5 zeolite catalyst which is not steam treated, using the reaction apparatus shown in FIG. 4, the C ₄ fraction shown in C ₅ fraction and Table 3 shown in Table 2 6: 4 ( (Weight ratio). That is, the molded catalyst was placed in a SUS reaction tube 21 having an inner diameter of 27.2 mmφ.
Then, the SUS reaction tube 21 was heated in an electric furnace 25 whose temperature could be adjusted by a thermocouple 24 for temperature adjustment so that the average temperature of the catalyst 23 measured by the thermometer 22 was 650 ° C. / Cm ² · G, H ₂ O partial pressure 0.8atm
The steam treatment was performed by supplying water or steam to the substantially fresh catalyst through the raw material inlet 26 for 6.2 hours under the conditions described in the above.

Thereafter, the temperature of the catalyst 23 was adjusted to be equal to 520 ° C. by using a thermocouple 24 for temperature adjustment, and the C ₅ fraction having the composition shown in Table 2 in the raw material tank 27 and the raw material tank 28 and the C ₄ fraction shown in Table 3
9:30, weight ratio 6: 4, pressure 5Kg / cm ² ·
G, temperature 520 ° C., WHSV (weight hourly space velocity)
The mixture was supplied to the catalyst 23 in the SUS reaction tube 21 for 48 hours under the condition of 8 hr ^-1 . The aromatic yields at 5 and 40 hours after the start of the feed were determined, as well as the amount of coke accumulated on the catalyst during the 48 hour reaction. Table 1 shows the results.

Example 2 No. 3 sodium silicate (manufactured by Fuji Chemical Co., Ltd., SiO ₂ 2
5 wt%, the Na ₂ O8 wt%) 6.75 kg H ₂ O2
3.0 kg, 0.186 kg of Al ₂ (SO ₄ ) ₃ .16H ₂ O (manufactured by Wako Pure Chemicals KK) and 0.198 kg of sulfuric acid (manufactured by Wako Pure Chemicals KK, purity 97%) In addition, a commercially available Z having a known SiO ₂ / Al ₂ O ₃ molar ratio as a seed crystal.
SM-5 (manufactured by NE-Chemcat, SiO ₂ / Al ₂
(O ₃ = 50) was added to obtain a homogeneous gel.

This gel was placed in a 50-liter autoclave and crystallized at 150 ° C. for 25 hours while stirring at a rotation speed of 200 rpm. The resulting slurry was filtered, washed with 5 times the amount of water, and dried at 120 ° C. for 5 hours. FIG. 5 shows a scanning electron micrograph of this zeolite. As is apparent from the figure, the ZSM-5 formed has a thickness of 0.5 to 1 μm at the widest part and an average of 0.7 μm.
m.

Next, the resulting catalyst was SiO ₂ / Al ₂ O.
_{The 3} molar ratio was determined in the same manner as in Example 1. Further, H-ZSM-5 containing 10% by weight of zinc was prepared in the same manner as in Example 1.
A zeolite shaped catalyst was obtained. 650 ° C of this molded catalyst
Of pyridine at 500 ° C. to 900 ° C. before and after steaming at 650 ° C., the first-order rate constant of n-hexane after steaming at 650 ° C. for 11 hours, and the ratio of surface acid points to total acid points. The same method as in Example 1 was used. Table 1 shows the results.

Further, the same test as in Example 1 for evaluating the regenerative deterioration resistance and the test for evaluating the coking resistance were performed using a catalyst which had been subjected to steam treatment at 650 ° C. for 11 hours. Table 1 shows the results.

Example 3 An aqueous solution of sodium silicate (SiO ₂ : 26% by weight, Na ₂
O: 7.0% by weight) To 8.0 kg of NaOH 0.05 kg
The solution was added H ₂ O4kg _{and, Al 2 (SO 4) 3} · 1
0.61 kg of 6H ₂ O and 0.1 k of 1,3-dimethylurea
g was dissolved in 15 kg of H ₂ O while stirring, and 10 kg of 5% by weight sulfuric acid was added to obtain a homogeneous gel. This gel was charged into a 50-liter autoclave, and stirred with a stirring power of 0.5 to 1 KW / m ² for 16 hours.
A synthesis reaction was performed at 0 ° C. for 10 hours to obtain a seed slurry.

Next, special No. 3 sodium silicate (Fuji Chemical Co., Ltd.)
(Manufactured by Sharp Corporation, SiO ₂ 25% by weight, Na ₂ O 8% by weight)
5.45 kg of H ₂ O 11.0 kg and Al ₂ (SO ₄ )
₃ · 16H (manufactured by Wako Pure Chemical Industries, K.K., Inc.) ₂ O 3.05kg
And sulfuric acid (Wako Pure Chemical Industries, Ltd., purity 97%) 3.
15 kg was added, and 11.67 kg of the slurry obtained above was added as a seed slurry to obtain a homogeneous gel. Put this gel in a 50 liter autoclave,
For 39.5 hours while stirring at a rotation speed of 110 rpm.

The resulting slurry was filtered, washed with 5 times the amount of water, dried at 120 ° C. for 5 hours, and the particle size of the zeolite was measured with a scanning electron microscope. Next, the SiO ₂ / Al ₂ O ₃ molar ratio of the obtained catalyst was determined in the same manner as in Example 1.

Further, an H-ZSM-5 zeolite molded catalyst containing 10% by weight of zinc was obtained in the same manner as in Example 1. Amount of pyridine desorbed from 500 ° C. to 900 ° C. before and after steam treatment at 650 ° C. for 5 hours, first order reaction rate constant of n-hexane after steam treatment at 650 ° C. for 9.5 hours, and surface of this molded catalyst The ratio between the acid sites and the total acid sites was determined in the same manner as in Example 1. Table 1 shows the results.

Further, the same test as in Example 1 for evaluating the regenerative deterioration resistance and the test for evaluating the coking resistance were carried out using a catalyst which had been subjected to steam treatment at 650 ° C. for 9.5 hours.
Table 1 shows the results.

Example 4 Special No. 3 sodium silicate (manufactured by Fuji Chemical Co., Ltd., SiO ₂ 2
5 wt%, H ₂ O95k to Na ₂ O8 wt%) 92 kg
g and Al ₂ (SO ₄ ) ₃ .16H ₂ O (Wako Pure Chemical Industries, Ltd.
K. 7.3 kg of sulfuric acid (manufactured by Wako Pure Chemicals KK, purity: 97%) and 1.15 kg of 1,3-dimethylurea dissolved in 150 kg of H ₂ O were added to the solution while stirring. A homogeneous gel was obtained. This gel was charged into a 600-liter autoclave, and stirred for 160 minutes.
A synthesis reaction was carried out at 30 ° C. for 30 hours to synthesize Na-type ZSM-5. The synthesized slurry was repeatedly filtered and washed with water until the filtrate PH became 8 or less, dried at 120 ° C. for 20 hours, and then calcined in air at 550 ° C. for 3 hours to form Na-type Z.
20 kg of SM-5 powder was obtained.

Special No. 3 sodium silicate (manufactured by Fuji Chemical Co., Ltd.)
SiO ₂ 25 wt%, Na ₂ O8 wt%) 92 kg in H ₂ O245kg and _{Al 2 (SO 4) 3 ·} 16H 2 O
7.3 kg (manufactured by Wako Pure Chemicals KK) and 3.8 kg of sulfuric acid (purity 97%, manufactured by Wako Pure Chemicals KK), and
3 kg of the Na-type ZSM-5 powder obtained above was added to obtain a homogeneous gel. This gel was charged into a 600-liter autoclave, and a synthesis reaction was performed at 150 ° C. for 10 hours with stirring to obtain a seed slurry.

Next, Special No. 3 sodium silicate (Fuji Chemical Co., Ltd.)
Company, SiO ₂ 25% by weight, Na ₂ O 8% by weight) 9
2 kg of H ₂ O 245 kg and Al ₂ (SO ₄ ) ₃・ 16
4.8 kg of H ₂ O (manufactured by Wako Pure Chemicals KK) and 4.9 kg of sulfuric acid (manufactured by Wako Pure Chemicals KK, purity: 97%) were added, and the slurry obtained above was used as a seed slurry. 167
kg was added to obtain a homogeneous gel. This gel was placed in a 600-liter autoclave, and crystallized at 160 ° C. for 45 hours while stirring at a rotation speed of 130 rpm.

While the obtained slurry was subjected to centrifugal filtration, PH was
Was reduced to 9 or less, and then dried at 120 ° C. for 5 hours. Scanning electron micrograph of the dried product
Shown in the figure. As is apparent from the figure, the Na-type ZSM formed
In the case of -5, the length of the widest part is 2-3 μm, and the average is 2.5 μm. Subsequently, the SiO ₂ / Al ₂ O ₃ molar ratio of the obtained dried product was measured by using a fluorescent X-ray apparatus and found to be 39.

Further, the dried product was ion-exchanged with a 10% by weight slurry in 1N nitric acid at room temperature for 3 hours, washed with water until the pH became 4.5 or more while centrifugally filtered, and further washed at 120 ° C. with 10% by weight. After drying for an hour, H-ZSM-5 was obtained. Dissolve 144g of zinc nitrate hexahydrate in 200g of water and 5g of acetic acid
Was added, 200 g of alumina sol (alumina sol 520 manufactured by Nissan Chemical Industries, Ltd.), 20 g of boehmite, and 200 g of H-ZSM-5 were added and mixed for 2 hours. The above clay-like mixture is 1.6 mm in diameter and 4 to 6 mm in length.
After being molded into a columnar shape, dried at 120 ° C. for 2 hours, and calcined in an electric furnace at 500 ° C. for 3 hours in an air atmosphere.
A H-ZSM-5 zeolite catalyst containing 5% by weight was formed.

Further, in the same manner as in Example 1, the obtained shaped catalyst was heated and degassed when it was formed into an H-form before and after steaming at 650 ° C. and a H ₂ O partial pressure of 0.8 atm for 5 hours. The elimination amount of pyridine at 500 to 900 ° C by the separation method was determined by the above method. Subsequently, 650 according to the method described above.
The first-order reaction rate constant of n-hexane and the ratio of surface acid sites to total acid sites of the catalyst which was subjected to steam treatment for 8 hours at a temperature of 0.8 ° C. and a partial pressure of H ₂ O of 0.8 atm were determined. The coking test was performed in the same manner as in Example 1. Table 1 shows the results.

Example 5 Special No. 3 sodium silicate (manufactured by Fuji Chemical Co., Ltd., SiO ₂ 2
5 wt%, the Na ₂ O8 wt%) 2300 kg H ₂ O2
375 kg, Al ₂ (SO ₄ ) ₃ · 16H ₂ O (manufactured by Wako Pure Chemicals KK) 183 kg, and sulfuric acid (Wako Pure Chemicals K.K.
K. A solution obtained by dissolving 95 kg of 95% (manufactured by K.K., purity: 97%) and 30 kg of 1,3-dimethylurea in 3750 kg of H ₂ O was added with stirring to obtain a homogeneous gel. 18m ^{3 of} this gel
Into an autoclave at 160 ° C. with stirring.
The synthesis reaction was performed for 0 hours to synthesize Na-type ZSM-5.
The synthesized slurry was repeatedly filtered and washed with water until the filtrate PH became 8 or less, dried at 120 ° C. for 30 hours, and then calcined in air at 550 ° C. for 3 hours to obtain Na-type ZSM-5.
520 kg of powder was obtained.

Special No. 3 sodium silicate (manufactured by Fuji Chemical Co., Ltd.)
SiO ₂ 25 wt%, Na ₂ O8 wt%) 1930k
5780 kg of H ₂ O and a sulfuric acid band (liquid sulfuric acid band manufactured by Sumitomo Chemical Industries, 8.1% by weight of aluminum oxide, pH
= 3.7) / water = 137 kg / 650 kg and sulfuric acid (purity 97%, manufactured by Wako Pure Chemicals KK) / water = 81 kg
/ 800 kg and 75 kg of the powder of the Na type ZSM-5 obtained above were added to obtain a homogeneous gel. This gel is 18
They were charged to an autoclave of m ^3, while stirring 150 ℃
For 10 hours to obtain a seed slurry.

Next, special No. 3 sodium silicate (Fuji Chemical Co., Ltd.)
Company, SiO ₂ 25% by weight, Na ₂ O 8% by weight) 1
To 910 kg, 5050 kg of H ₂ O, a sulfuric acid band (liquid sulfuric acid band manufactured by Sumitomo Chemical Co., aluminum oxide 8.1% by weight, pH = 3.7) / water = 196 kg / 930 kg, and sulfuric acid (manufactured by Wako Pure Chemicals KK) (Purity 97%) / water = 7
0 kg / 800 kg was added, and 4480 kg of the seed slurry obtained above was added as a seed slurry to obtain a homogeneous gel. Put this gel to 18m ³ autoclave, 1
Crystallization was carried out at 60 ° C. for 20 hours while stirring at a rotation speed of 40 rpm.

The slurry was centrifugally filtered and the pH was adjusted.
Is washed with water until it becomes 9 or less.
After ion exchange with the weight% slurry at 70 ° C. for 5 hours,
While centrifugal filtration, wash with water until the pH becomes 4.5 or more,
Dry at 120 ° C. for 30 hours. A scanning electron micrograph of the dried product is shown in FIG. As is apparent from the figure, the H-ZSM-5 generated has a widest part having a length of 2 to 2.
It can be seen that the average diameter is 3 μm and the average is 2.5 μm. continue,
The SiO ₂ / Al ₂ O ₃ molar ratio of the obtained dried product was determined by fluorescence X
It was 41 when measured using the wire apparatus.

Dissolve 144 g of zinc nitrate hexahydrate in 200 g of water and add 5 g of acetic acid. 200 g of alumina sol (Alumina sol 520 manufactured by Nissan Chemical Industries, Ltd.) and boehmite 20
g, and 200 g of the above H-ZSM-5 were added and mixed for 2 hours. The above mixture in the form of clay is 1.6 mm in diameter,
After molding into a column having a length of 4 to 6 mm, drying at 120 ° C. for 2 hours, firing in an electric furnace at 500 ° C. for 3 hours in an air atmosphere to form an H-ZSM-5 zeolite catalyst containing 10% by weight of zinc. did.

Further, in the same manner as in Example 1, the temperature of the obtained molded catalyst was changed to H-type before and after steam treatment for 5 hours at 650 ° C. and a H ₂ O partial pressure of 0.8 atm. The elimination amount of pyridine at 500 to 900 ° C. by the elimination method was determined by the above method. Subsequently, 650 according to the method described above.
The primary reaction rate constant of n-hexane and the ratio of surface acid points to total acid points of the catalyst which was subjected to steam treatment for 8.5 hours at a temperature of 0.8 ° C. and a partial pressure of H ₂ O of 0.8 atm were determined. And a coking resistance test were conducted in the same manner as in Example 1.
Table 1 shows the results.

Comparative Example 1 (1) Synthesis of Seed Slurry Aqueous sodium silicate solution (SiO ₂ : 25.2% by weight, N
a ₂ O: 7.35 wt.%) NaOH0.64 to 129g
g and H ₂ O 133 g were added to the solution, and Al ₂ (SO ₄ ) was added.
₃ · 16H _{2 O0.9.7g} and 1,3-dimethylurea 0.2g added with stirring a solution prepared by dissolving in H ₂ O230g, to obtain a homogeneous gel by the addition of 4.6 wt% sulfuric acid 140g . The pH of this gel was 10.8. This gel was charged into a 1 liter autoclave, and a synthesis reaction was performed at 180 ° C. for 40 hours. 30 ° C. of the obtained slurry
After cooling, a portion was filtered and dried at 120 ° C. for 8 hours. Its X-ray diffraction pattern was consistent with ZSM-5.

(2) Main Synthesis 250 g of the seed slurry obtained in (1) was added to 400 g of the gel having the same composition as in (1), mixed well, and then placed in a 1 liter autoclave and crystallized at 160 ° C. for 15 hours. Was. The resulting slurry was filtered, washed with 5 times the amount of water, and dried at 120 ° C. for 8 hours. The X-ray diffraction pattern of the slurry was consistent with that of ZSM-5. FIG. 8 shows a scanning electron micrograph of this zeolite. As is clear from the figure, the generated ZSM-5 is formed by agglomeration of fine particles, and the agglomerates are particles having irregularities on the surface where the thickness of the widest part is about 0.2 μm. . Next, the SiO ₂ / Al ₂ O ₃ molar ratio of the obtained catalyst was determined in the same manner as in Example 1.

In the same manner as in Example 1, an H-ZSM-5 zeolite molded catalyst containing 10% by weight of zinc was obtained. Amount of pyridine desorbed at 500 ° C. to 900 ° C. before and after steam treatment at 650 ° C. for 5 hours, and first-order reaction rate constant and surface of n-hexane after steam treatment at 650 ° C. for 3.8 hours. The ratio between the acid sites and the total acid sites was determined in the same manner as in Example 1. Table 1 shows the results.

Further, a test for evaluating regenerative deterioration resistance and a test for evaluating coking resistance were conducted in the same manner as in Example 1 using a catalyst which had been subjected to steam treatment at 650 ° C. for 3.8 hours.
Table 1 shows the results. The particle diameter is small, the ratio of surface acid sites to the total acid sites is large, and the parameter α for the amount of pyridine desorbed is large, so that the regeneration deterioration resistance is poor and the coke accumulation amount in the coking resistance test is large. I understand.

Comparative Example 2 1,8-Diamino-4-aminomethyloctane 100
g, 4 g of aluminum sulfate and 5 g of sodium hydroxide.
00g, and silica sol (30% SiO ₂ )
250 g was added to obtain a homogeneous solution. While stirring this solution, 20% sulfuric acid was added dropwise to adjust the pH to 12.5 to obtain a homogeneous gel. Further, the gel was put into a mixer and stirred at a high speed of 2000 rpm for 20 minutes. Charge this gel into an autoclave and stir at 50 rpm,
Crystallized at 150 ° C. for 24 hours. The obtained slurry was filtered, washed with 5 times the amount of water, dried at 120 ° C. for 8 hours, and the particle size of the catalyst was measured with a scanning electron microscope to find that it was 5 μm or more.

Further, an H-ZSM-5 zeolite molded catalyst containing 10% by weight of zinc was obtained in the same manner as in Example 1. The amount of pyridine desorbed between 500 ° C. and 900 ° C. before and after steaming at 650 ° C. for 5 hours, and 1 hour at 650 ° C.
The first-order rate constant of n-hexane and the ratio of surface acid sites to total acid sites after steaming for 6 hours were determined in the same manner as in Example 1. Table 1 shows the results.

Further, a test for evaluating the regenerative deterioration resistance and a test for evaluating the coking resistance were conducted in the same manner as in Example 1 using a catalyst which had been subjected to a steam treatment at 650 ° C. for 16 hours. Table 1 shows the results. From Table 1, it can be seen that the catalyst has a large particle size and a small ratio of surface acid points to total acid points, and thus has good regenerative deterioration resistance, but is rapidly deteriorated by coking.

Comparative Example 3 Special No. 3 sodium silicate (manufactured by Fuji Chemical Co., Ltd., SiO ₂ 2
5 wt%, the Na ₂ O8 wt%) 6.75 kg H ₂ O2
3.0 kg, 0.41 kg of Al ₂ (SO ₄ ) ₃ · 16H ₂ O (manufactured by Wako Pure Chemicals KK) and 0.198 kg of sulfuric acid (manufactured by Wako Pure Chemicals KK, purity 97%) In addition, a commercially available Z having a known SiO ₂ / Al ₂ O ₃ molar ratio as a seed crystal.
SM-5 (manufactured by NE-Chemcat, SiO ₂ / Al ₂
O ₃ = 25) was added to obtain a homogeneous gel. Put this gel in a 50 liter autoclave,
Crystallization was performed at 150 ° C. for 25 hours while stirring at a rotation speed of 200 rpm. After filtering the resulting slurry, 5
It was washed with twice the amount of water and dried at 120 ° C. for 5 hours. The SiO ₂ / Al ₂ O ₃ molar ratio of this zeolite was determined by the same method as in Example 1 to be 18.

Further, an H-ZSM-5 zeolite molded catalyst containing 10% by weight of zinc was obtained in the same manner as in Example 1. The amount of pyridine desorbed between 500 ° C. and 900 ° C. before and after the steam treatment at 650 ° C. for 5 hours, and 3 minutes at 650 ° C.
The first-order rate constant of n-hexane and the ratio of surface acid sites to total acid sites after steam treatment for a period of time were determined in the same manner as in Example 1. Table 1 shows the results.

Further, a test for evaluating the regenerative deterioration resistance and a test for evaluating the coking resistance were carried out in the same manner as in Example 1 using a catalyst which had been subjected to steam treatment at 650 ° C. for 3 hours. Table 1 shows the results. Since the molar ratio of SiO ₂ / Al ₂ O ₃ is small, the degradation resistance against reproduction is poor.

Comparative Example 4 The primary particle diameter was measured using a commercially available H-ZSM-5 zeolite (manufactured by NE-Chemcat, SiO ₂ / Al ₂ O ₃ = 250), and the same method as in Example 1 was used. 10 zinc
An H-ZSM-5 zeolite shaped catalyst containing 5% by weight was obtained.
The amount of pyridine desorbed at 500 ° C. to 900 ° C. before and after steaming at 650 ° C. for 5 hours, the first-order reaction rate constant of n-hexane after steaming at 650 ° C. for 1 hour, and the surface acid point of this shaped catalyst And the ratio of total acid sites was determined by the same method as in Example 1. Table 1 shows the results.

Further, a test for evaluating the regenerative deterioration resistance and a test for evaluating the coking resistance were conducted in the same manner as in Example 1 using a catalyst which had been subjected to steam treatment at 650 ° C. for 1 hour. Table 1 shows the results. Since the molar ratio of SiO ₂ / Al ₂ O ₃ is too large and the crystallinity is low, the parameter α of the amount of pyridine desorbed before and after the steam treatment becomes large, and the degradation resistance against regeneration is poor.

Comparative Example 5 290 g of sodium silicate (water glass No. 3) was added to distilled water 230
A dissolved in g, separately aluminum sulfate 16 hydrate 1
Liquid B was prepared by dissolving 1.4 g, 23.4 g of 1,3-dimethylurea and 13 g of sulfuric acid in 300 g of distilled water.
Then, using a homogenizer, the solution A was added to the solution A while stirring it vigorously, and the mixture was stirred for about 3 hours until the gel composition became uniform. This gel composition was charged into a 1 liter autoclave and allowed to react and crystallize under stirring at 150 ° C. and 1000 rpm for 35 hours. After the reaction, the solid is filtered, washed with water, dehydrated,
It was dried and calcined at 550 ° C. for 3 hours in air. SiO ₂ / Al _{2 of the} obtained H-ZSM-5 type zeolite
The O ₃ molar ratio was determined by the same method as in Example 1.
Met. The particle size of the zeolite was measured by a scanning electron microscope.

Further, a ZSM-5 zeolite molded catalyst containing 10% by weight of zinc was obtained in the same manner as in Example 1. Before and after the steam treatment at 650 ° C. for 5 hours,
The amount of pyridine desorbed from 0 ° C to 900 ° C was determined. The first-order rate constant of n-hexane after steaming at 650 ° C. for 3 hours and the ratio of surface acid sites to total acid sites were determined in the same manner as in Example 1. Table 1 shows the results. Furthermore, at 650 ° C., 3
Using the catalyst subjected to the steam treatment for a period of time, the same test as in Example 1 for evaluating the regenerative deterioration resistance and the test for evaluating the coking resistance were performed. Table 1 shows the results. Since the parameter α of the amount of pyridine desorbed before and after the steam treatment is as large as 1.8,
Poor regeneration deterioration resistance.

Comparative Example 6 Commercially available H-ZSM-5 zeolite (SiO ₂ / Al ₂ O)
₃ = 400), and then the H-ZSM-5 containing 10% by weight of zinc was measured in the same manner as in Example 1.
A zeolite shaped catalyst was obtained. 650 ° C of this molded catalyst
The amount of pyridine desorbed at 500 ° C. to 900 ° C. before and after the steam treatment for 5 hours, the first-order reaction rate constant of n-hexane before the steam treatment, and the ratio of the surface acid sites to the total acid sites were the same as in Example 1. I stopped in the same way. Table 1 shows the results. Furthermore,
Using a catalyst not subjected to steam treatment, the same test as in Example 1 for evaluating regenerative degradation resistance and the test for evaluating coking resistance were performed. Table 1 shows the results. SiO ₂ / Al ₂
Since the O ₃ molar ratio is too large, the activity is low and the aromatic yield is low.

Example 6 A zeolite catalyst synthesized and molded in the same manner as in Example 4 was charged into a one-stage adiabatic reactor, and a pressure of 5 kg / cm ² ···
G, steam treatment at 650 ° C. for 8 hours. Further, the C ₅ fraction shown in Table 2 and the C ₄ fraction shown in Table 3 were mixed at a weight ratio of 6: 4 at a pressure of 5 kg / cm ² · G, an inlet temperature of 530 ° C.
The cyclization reaction was carried out under a condition of WHSV (weight hourly space velocity) of 2.8 hr ^-1 for 48 hours. The carbonaceous material accumulated during 48 hours is subjected to a pressure of 5 kg / cm ² · G, 480 to 5
In a 30 ° C. atmosphere, a nitrogen gas having an oxygen concentration of 1 to 1.5 vol% was circulated at a flow rate of 5000 Nm 3 / hr for 40 to 43 hours to perform combustion removal (regeneration). The above cyclization reaction and regeneration were repeated 75 times (300 days). 1st time and 7
Table 4 shows the results of the fifth cyclization reaction.

Comparative Example 7 A zeolite catalyst synthesized and formed in the same manner as in Comparative Example 1 was charged into a one-stage adiabatic reactor, and a pressure of 5 kg / cm ² ···
G, steam treatment at 650 ° C. for 3.8 hours. Further, the C ₅ fraction shown in Table 2 and the C ₄ fraction shown in Table 3 were mixed at 6: 4.
5 kg / cm ² · G, inlet temperature 53
A cyclization reaction was carried out at 0 ° C. and under a condition of WHSV (weight hourly space velocity) of 2.8 hr ⁻¹ for 48 hours. The carbonaceous material accumulated during 48 hours was subjected to a pressure of 5 kg / cm ² · G, 48
In an atmosphere of 0 to 530 ° C, an oxygen concentration of 1 to 1.5 vol%
Nitrogen gas at a flow rate of 5000 Nm3 / hr from 40 to 43
The mixture was burnt and removed (regenerated) by circulating for a time. The above cyclization reaction and regeneration were repeated 75 times (300 days). Table 4 shows the results of the first and 75th cyclization reactions. It can be seen that since the ratio of the surface acid point to the total acid point is large, the degradation resistance against regeneration is poor and the permanent activity degradation is fast.

Example 7 The catalyst obtained in Example 4 and subjected to steam treatment at 650 ° C. for 8 hours was subjected to atomic absorption spectrometry after the total zinc content was determined by X-ray fluorescence and the catalyst was treated with hydrochloric acid. To obtain zinc oxide.
The weight of the catalyst was 2.9% by weight of zinc oxide and 22.4% by weight of zinc aluminate. 10 g of this catalyst was charged into a reaction tube, and hydrogen was passed at 20 [L / Hr] at 500 ° C for 20 hours
To reduce. Table 5 shows the measurement results of the amounts of zinc oxide and zinc aluminate before and after the hydrogen reduction. Also, using the catalyst before and after hydrogen reduction, the C ₄ fraction and C ₅
A test was conducted to evaluate the coking resistance using the fraction. Table 5 shows the results.

Comparative Example 8 100 g of zinc-free H-ZSM-5 obtained in Example 4 was immersed in a 7% by weight aqueous solution of zinc nitrate, evaporated to dryness, dried at 120 ° C. for 4 hours, and then dried at 500 ° C. By calcining for 3 hours, a catalyst containing 2.0% by weight of zinc was prepared. Then, this catalyst was compression-molded, pulverized and crushed to a size of 9 to 20 mesh, and 20 g of the catalyst was charged into a quartz glass reactor having an inner diameter of 12 mm. Heat treatment was performed at 650 ° C. for 1 hour under atmospheric pressure. Fluorescent X
Of zinc oxide and zinc aluminate by X-ray and atomic absorption spectrometry,
Hydrogen reduction was performed in the same manner as in Example 8. Further, a test was conducted to evaluate the coking resistance using the C ₄ cut and the C ₅ cut before and after hydrogen reduction. Table 5 shows the results.

Comparative Example 9 The H-ZSM-5 containing no zinc obtained in Example 1 was subjected to steam treatment at 650 ° C. for 5 hours, and zinc aluminate manufactured by Kojundo Chemical Laboratory was used as a total catalyst as zinc. Were mixed so that the concentration with respect to 10% by weight. Evaluation test the coking resistance with C ₄ fraction and a C ₅ fraction were performed. Table 5 shows the results.

[0114]

[Table 1]

[0115]

[Table 2]

[0116]

[Table 3]

[0117]

[Table 4]

[0118]

[Table 5]

[0119]

According to the method of the present invention as described above, the amount of carbonaceous material accumulated on the catalyst during the reaction in which the raw material or product contains an aromatic hydrocarbon is reduced, and Suppresses a temporary decrease in activity due to the quality of the carbonaceous material, and further occurs when the carbonaceous material is burnt off with an oxygen-containing inert gas,
It is possible to suppress permanent activity deterioration due to dealumination in a high-temperature atmosphere in which water is present, that is, to obtain a catalyst excellent in regenerative deterioration resistance and coking resistance. Therefore, the method of the present invention can be widely used in the petrochemical industry and petroleum refining, and can be particularly effectively used in the production of aromatic compounds and high octane gasoline.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an acid point measuring device in the method of the present invention.

FIG. 2 is a schematic diagram of an isothermal reactor in the method of the present invention.

FIG. 3 is a scanning micrograph of a catalyst in the method of the present invention.

FIG. 4 is a schematic view of an isothermal reactor in the method of the present invention.

FIG. 5 is a scanning micrograph of a catalyst in the method of the present invention.

FIG. 6 is a scanning micrograph of a catalyst in the method of the present invention.

FIG. 7 is a scanning micrograph of a catalyst in the method of the present invention.

FIG. 8 is a scanning micrograph of a catalyst in the method of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Gas flow meter 2 Tubular electric furnace 3 SUS short tube column 4 Sample 5 Inlet 6 FID type detector 7 Temperature detection end 8 Ribbon heater 9 Heat insulator 10 Quartz reaction tube 11 Quartz wool 12 Catalyst 13 Raschig ring 14 Thermometer 15 Temperature Thermocouple for adjustment 16 Electric furnace 17 Inlet for raw material 18 Condenser 19 Oil trap 20 Bag for repairing generated gas 21 SUS reaction tube 22 Thermometer 23 Catalyst 24 Thermocouple for temperature control 25 Electric furnace 26 Raw material inlet 27 C ₅ fraction Raw material tank 28 C ₄ fraction raw material tank 29 pump 30 pump

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location // C07B 61/00 300 C07B 61/00 300 (72) Inventor Jiro Kinoshita Shiori, Kurashiki-shi, Okayama Prefecture 3-13-1 Sanyo Petrochemical Co., Ltd.

Claims (10)

[Claims] 1. A high silica zeolite-based catalyst used in a reaction in which an aromatic hydrocarbon is contained in a raw material or a product, and satisfies the following requirements (1), (2), (3), and (4). High silica zeolite catalyst. (1) Si of zeolite constituting the zeolite catalyst
O ₂ / Al ₂ O ₃ molar ratio of 20 to 200. (2) The primary particles of the zeolite constituting the zeolite catalyst have a particle size of 0.3 to 3 μm. (3) The ratio of surface acid sites to all acid sites when the zeolite-based catalyst is H-type is 0.03 to 0.15. (4) The zeolite-based catalyst is treated with a H ₂ O partial pressure of 0.8 atm,
After steam treatment at 650 ° C. for 5 hours, the amount of pyridine desorbed (B) at 500 to 900 ° C. by the temperature-programmed desorption method when the H-form was formed and the H-form before the steam treatment The pyridine desorption amount (A) at 500 to 900 ° C. by the thermal desorption method satisfies the following. (Equation 1) 2. The catalyst according to claim 1, wherein the reaction is a reaction for producing an aromatic hydrocarbon from a light hydrocarbon containing olefin and / or paraffin. 3. The first-order rate constant of the decomposition of n-hexane of a zeolite catalyst measured at 500 ° C. under atmospheric pressure is 0.1.
The catalyst according to claim 1, wherein the number is 2 or more. 4. A high-silica zeolite-based catalyst comprising a zeolite and a group VIII, Ib, IIb or I
The catalyst according to any one of claims 1 to 3, comprising a mixture of a metal belonging to Group IIb and at least one selected from compounds thereof. 5. The catalyst according to claim 4, wherein the high silica zeolite-based catalyst is a mixture of zeolite, a zinc component and alumina. 6. The catalyst according to claim 4, wherein the high silica zeolite-based catalyst is a mixture of zeolite, a zinc component and alumina, and is heat-treated in steam. 7. The catalyst according to claim 4, wherein the high silica zeolite-based catalyst is a mixture of a mixture of a zinc component and alumina heat-treated in steam and a mixture of zeolite. 8. The high silica zeolite-based catalyst contains both zinc aluminate and zinc oxide.
The catalyst as described. 9. The catalyst according to claim 8, wherein the high silica zeolite-based catalyst contains both 8.2 to 50% by weight of zinc aluminate and 1.2 to 20% by weight of zinc oxide. 10. A process for producing an aromatic hydrocarbon from a light hydrocarbon containing olefins and / or paraffins using the catalyst according to any one of claims 1 to 9.