JPH10244161A - Zeolite film and its production and production of olefin using zeolite film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel zeolite film excellent in heat stability and having high mechanical strength and also excellent in molecular sieve performance and a catalytic performance for dimerizing dehydrating reaction of alcohol, to provide its production method and to provide the production of olefin using the zeolite film. SOLUTION: The zeolite film is constituted by forming the zeolite film on a surface of a porous metallic oxide carrier in which fine pores at the surface are filled with particles of metallic oxide or metallic nitride and by laminating a particle layer of metallic oxide or metallic nitride and the zeolite film in order on the surface of the porous metallic oxide carrier. After coating the surface of the porous metallic oxide carrier with the particles of the metallic oxide or the metallic nitride having an amount capable of at least filling an inside of the pores at the surface, the seed crystal for forming the zeolite film is cladded on the coated layer, then the zeolite film is formed on the surface to which the seed crystal is cladded. Then, the zeolite film is used at the time of executing simultaneously the dimerizing dehydrating reaction and separation of the formed olefin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a zeolite membrane, a method for producing the same, and a method for producing an olefin using the zeolite membrane.

[0002]

2. Description of the Related Art Zeolite is an alkali or alkaline earth element aluminum silicate, and various crystal forms are known. The membrane is obtained by supporting a porous metal oxide, and is expected to be used as various kinds of separation membranes and catalysts. Such a zeolite membrane is basically
For example, as disclosed in JP-A-63-291809, an aqueous mixture containing a silica source and an alkali metal source or an alkaline earth metal source is hydrothermally reacted in the presence of an alumina porous carrier. I can do it.

[0003] Usually, after the above-mentioned hydrothermal reaction, a calcination treatment is carried out, and the zeolite membrane having a desired thickness can be obtained by laminating the zeolite membrane by repeatedly performing the hydrothermal reaction and calcination. Further, when the activity of the zeolite membrane is reduced, it can be recovered by a baking treatment.

[0004] By the way, conventionally known zeolite membranes are liable to cause cracks and pinholes during the above-mentioned calcination treatment, and cannot be said to have sufficient mechanical strength. Further, conventionally known zeolite membranes have room for improvement in terms of molecular sieving ability, and furthermore, there is a problem that when used in a method for producing olefins by dimerization and dehydration of alcohol, the catalytic performance is low. .

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a catalyst having a high thermal stability and a high mechanical strength, a molecular sieve ability and a dimerization dehydration reaction of alcohol. An object of the present invention is to provide a novel zeolite membrane having excellent performance, a method for producing the same, and a method for producing an olefin using the zeolite membrane.

[0006]

Means for Solving the Problems The present inventors have made intensive studies in order to achieve the above object, and have obtained the following findings. That is, cracks and pinholes in the zeolite membrane formed on the surface of the porous carrier are generated by a difference in thermal expansion between the zeolite membrane and the porous carrier during firing. In addition, the above cracks and pinholes, when the coefficient of thermal expansion of the zeolite crystal is larger than the porous carrier,
Zeolite crystals formed in the pores on the surface of the porous carrier are also generated by expanding the porous carrier by expanding during firing. However, by interposing an intermediate layer made of a specific material between the porous carrier and the zeolite membrane so that the stress caused by the difference in thermal expansion is not applied to the zeolite membrane, the above-described cracks and pinholes are not generated. The zeolite membrane having such an intermediate layer is excellent in molecular sieving ability and catalytic performance in dimerization and dehydration of alcohol.

The present invention has been completed based on the above findings, and a first gist is a porous metal oxide carrier in which pores on the surface are filled with metal oxide or metal nitride particles. The second gist of the present invention resides in that a zeolite membrane is formed by forming a zeolite membrane on the surface of a metal oxide or metal nitride particle layer and a zeolite membrane on a surface of a porous metal oxide carrier. A zeolite membrane characterized by being sequentially laminated.

[0008] A third gist of the present invention is to cover the surface of the porous metal oxide carrier with an amount of metal oxide particles or metal nitride particles capable of filling at least the pores of the surface. There is provided a method for producing a zeolite membrane, which comprises applying a seed crystal for forming a zeolite membrane to the coated surface, and then forming a zeolite membrane on the surface on which the seed crystal has been applied.

Further, a fourth gist of the present invention is to provide a method for producing an olefin by a dimerization dehydration reaction of alcohol using a zeolite membrane, wherein the zeolite membrane or the zeolite membrane obtained by the above-mentioned method is used. Wherein the olefin produced at the same time as the dehydration-dimerization reaction is separated from the olefin produced using the zeolite membrane.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
First, for convenience of explanation, a method for producing a zeolite membrane according to the present invention will be described. In the method for producing a zeolite membrane according to the present invention, a porous metal oxide carrier, metal oxide particles or metal nitride particles, and a seed crystal for forming a zeolite membrane are used.

As the metal oxide of the porous metal oxide carrier, an oxide of a metal such as Al, Mg and Zr is usually used. Shirasu and the like can also be used as a natural raw material. The above metal oxides and the like are processed into a porous carrier by a known method. For example, in the case of a porous alumina carrier, a method is employed in which alumina powder is compression molded at ²⁰ to 2,000 Kg / cm ² and then calcined at 500 to 1200 ° C.

[0012] The pore diameter of the porous metal oxide support is usually 0.1 to 5 µm, preferably 0.1 to 0.5 µm. The shape of the porous metal oxide support is not particularly limited, but is generally a cylindrical type or a flat type. In the case of a zeolite membrane used in a method for producing an olefin described below,
From the viewpoint of handleability, a cylindrical porous metal oxide carrier is preferably used.

The metal oxide particles or metal nitride particles are
An intermediate layer is formed between the porous metal oxide support and the zeolite membrane to prevent crystal growth of zeolite in pores on the surface of the porous metal oxide support. As the metal oxide particles or metal nitride particles, SiO ₂ , ZrO ₂ , TiO
_{2, Nb 2 O 3, Si} 3 N 4 or the like is used. These average particle sizes are the same size as the pore size of the porous metal oxide support,
That is, usually 0.1 to 5 μm, preferably 0.1 to
It is 0.5 μm.

As a seed crystal for forming a zeolite membrane, zeolite particles or a zeolite precursor solution is used.
As the zeolite particles, pulverized zeolite is suitably used, and the average particle size is usually 1 μm or less, preferably 0.5 μm or less. Although the chemical composition of the zeolite particles is substantially the same as the zeolite membrane to be formed, the structure may be crystalline or partially amorphous. The zeolite precursor solution is a solution for preparing a zeolite membrane used when forming a zeolite membrane by a hydrothermal reaction, the details of which will be described later. Material molar ratio (Si
_{O 2 / Al 2 O 3)} 20~40 aqueous medium solutions.

First, in the method for producing a zeolite membrane according to the present invention, the surface of a porous metal oxide support is coated with metal oxide particles or metal nitride particles. This coating is
At least, it is necessary that the inside of the pores on the surface of the porous metal oxide carrier be filled with metal oxide or metal nitride particles. In this case, the metal oxide particles or metal nitride particles are preferably used as a sol in order to achieve a uniform surface coating of the porous metal oxide carrier.

In the preparation of the above sol, it is preferable to use a surfactant from the viewpoint of the dispersibility of the metal oxide particles or metal nitride particles. The type of surfactant is not particularly limited, and may be any of nonionic, anionic, and cationic surfactants. In the above sol, the concentration of the metal oxide particles or the metal nitride particles is usually 1 to 3.
It is 0% by weight, preferably 5 to 25% by weight, and the concentration of the surfactant is appropriately selected in consideration of the dispersibility of the particles.
The remainder is generally water.

The surface coating of the porous metal oxide carrier with the sol is carried out by a method in which the porous metal oxide carrier is impregnated with the sol and then dried.
The drying temperature is from room temperature to 250 ° C. for 50 hours. Incidentally, the coating layer of the metal oxide particles or metal nitride particles,
It is converted into a dense layer by the hydrothermal reaction described below.

Thereafter, in the present invention, a seed crystal (zeolite particle or zeolite precursor solution) for forming a zeolite film is formed on the coated surface of the metal oxide particles or metal nitride particles.
To adhere. In this case, the zeolite particles may be used as a dispersion. Depending on the form of the adherend, the porous metal oxide carrier coated with metal oxide particles or metal nitride particles may be coated with the zeolite particles in addition to the impregnation method (immersion method), the coating method, and the spray method. And a method of rolling.

Next, in the present invention, a zeolite membrane is formed on the surface on which the seed crystal is adhered, and a hydrothermal reaction of a zeolite precursor solution is suitably used for the formation of the zeolite membrane. The crystal type of the zeolite membrane to be formed is not particularly limited, and may be any of MFI type, A type, Y type, mordenite type, beta type and the like.

The zeolite precursor solution is usually an aqueous medium solution containing an aluminum source and a silicon source and an alkali metal source and / or an alkaline earth metal source. As the aluminum source, aluminum salts such as aluminum sulfate, aluminum nitrate, and aluminum chloride are usually used. As the silicon source, alkali metal silicates such as sodium metasilicate, sodium orthosilicate, water glass, and potassium metasilicate are usually used. Examples of the alkali (earth) metal source include sodium chloride, potassium chloride, calcium chloride, and magnesium chloride. The above-mentioned alkali metal silicate can be used as a raw material also serving as an alkali metal. Other raw materials include alumina powder, colloidal alumina, silica powder, silicic acid, colloidal silica, fused silica, and the like.

The molar ratio of the silica raw material and the alumina raw material (Si
O ₂ / Al ₂ O ₃ ) is appropriately determined depending on the intended composition of the zeolite, but a preferred example is 20 to 40. Further, the usage ratio of the alkali metal source and / or the alkaline earth metal source can be appropriately determined. The raw material concentration in the zeolite precursor solution is not particularly limited,
The concentration of the silicic acid raw material is usually 5% by weight in terms of Si.
Or less, preferably 3% by weight or less, more preferably 2.5% by weight or less.
% By weight or less. Under such low concentration conditions, a more dense zeolite membrane is formed.

The hydrothermal reaction is usually carried out at 40 to 200 ° C. and 0 to 200 ° C.
The reaction is performed under the condition of 25 kg / cm ² G, and the reaction time is as follows:
30 minutes to 240 hours. After the completion of the hydrothermal reaction, drying and baking are performed. At this time, the rate of temperature rise is preferably 1 ° C./min or less, more preferably 0.5 ° C./min or less. With such a temperature raising rate condition, generation of cracks and pinholes in the zeolite membrane can be more completely prevented.

Next, the zeolite membrane according to the present invention will be described. The greatest feature of the zeolite membrane according to the present invention is that
The point is that the pores on the surface of the porous metal oxide used as the carrier of the zeolite membrane are filled with particles of the metal oxide or metal nitride. The preferred zeolite membrane according to the present invention has a layer structure of porous metal oxide carrier / particle layer (intermediate layer) of metal oxide or metal nitride / zeolite membrane. In any of the above-mentioned zeolite membranes, the above-mentioned particles are filled in the pores on the surface of the porous carrier, and the zeolite crystals do not substantially exist. That is, when forming a zeolite membrane on the surface of the intermediate layer,
Due to the buffering action of the intermediate layer, crystallization and growth of zeolite in the pores are prevented.

Therefore, in the zeolite membrane according to the present invention, the difference in thermal expansion between the zeolite crystal and the porous metal oxide carrier during the sintering in the production process and the activity recovery step is buffered by the intermediate layer. And as a result,
The zeolite membrane has substantially no pinholes or cracks. Note that the pinholes and cracks referred to here are minute ones that cannot be observed with a scanning electron microscope.

The above-mentioned intermediate layer constitutes a filter together with the porous metal oxide carrier, but is a dense layer as compared with a coarse layer of the porous metal oxide carrier. Therefore, the zeolite membrane according to the present invention has excellent molecular sieving ability due to the presence of the dense intermediate layer. Usually, the pore diameter of the porous metal oxide carrier is about 0.1 to 5 μm, and the pore diameter of the dense intermediate layer is about 10 ^{−3 to} 0.1 μm.

After repeated firing of the zeolite membrane, 3
Para-, meta-xylene and pa were performed at 0 ° C.
The separation coefficient α of the para / meta body determined from the gas permeation experiment using a single component system of ra-, meta-diethylbenzene was 2.5 in the case of xylene and 6.0 in the case of diethylbenzene. In this case, the transmission coefficients of para-xylene and para-diethylbenzene are respectively 7 × 10 ⁻¹¹ and 1.8 × 10 ⁻¹¹ mol · m · (m
² · s · Pa) ⁻¹ . On the other hand, the separation coefficient α of the zeolite membrane obtained in Comparative Example 1 described later was 1.
From this, it was found that the isomers could not be separated at the zeolite grain boundaries facing the pinholes and crack holes.

As a result of calculation based on the diffusion coefficient and the separation coefficient in the zeolite crystal, the zeolite membrane according to the present invention showed 99.99999999 on the outer surface of the filter.
6% will be covered by virtually perfect zeolite crystals. Therefore, it is considered that the zeolite membrane of the present invention exerts a remarkable molecular sieving ability. In addition, the above gas permeation experiment involves an operation of separating the zeolite membrane from the sample table with a disk-shaped diamond cutter during each baking, and the zeolite membrane receives a strong impact. The value of the separation coefficient of the zeolite membrane did not change. In addition, the value of the separation coefficient did not change even when firing was repeatedly performed at a temperature of 500 ° C. or higher.
This also indicates that the zeolite membrane of the present invention has excellent mechanical strength and thermal shock resistance.

In the zeolite membrane of the present invention, the thickness of each layer is not particularly limited, but the thickness of the porous metal oxide carrier is usually 1 to 50 mm, preferably 2 to 30 mm, and the thickness of the above-mentioned intermediate layer is , Usually 0.05 to 2 μm, preferably 0.1 to 1 μm, and the thickness of the zeolite membrane formed on the intermediate layer is usually 5 to 200 μm, preferably 10 to 50 μm.
μm.

Next, the method for producing an olefin according to the present invention will be described. In the present invention, the olefin generated at the same time as the alcohol dehydration reaction is separated using the above-mentioned zeolite membrane. In the above reaction, an ether is obtained by a dimerization reaction of an alcohol, and an olefin is obtained by a dehydration reaction. The side reactions include the production of paraffins from olefins and the production of aromatic compounds from paraffins.

As the zeolite membrane, a cylindrical type is usually used. The MFI type is particularly preferable as the crystal type. As the raw material alcohol, an aliphatic alcohol having 1 to 10 carbon atoms is usually used, and a practically preferable raw material is methyl alcohol.

As the reaction apparatus, for example, a zeolite membrane is arranged in an inner space of a tubular reactor provided with a heater, and the reactor communicates with a space (external space of the zeolite membrane) between the tubular reactor and the zeolite membrane. It has a carrier gas inlet (A) and a reaction gas inlet, has a carrier gas inlet (B) that communicates with the inner space of the zeolite membrane, and has an extra-membrane product outlet that communicates with the outer space of the zeolite membrane. A reaction apparatus comprising a zeolite membrane and an in-membrane product outlet that communicates with the internal space of the zeolite membrane can be used.

The reaction temperature is usually from 200 to 500 ° C, preferably from 350 to 450 ° C. The reaction is usually carried out under a negative pressure in the internal space of the zeolite membrane, and the differential pressure between the inside and outside of the zeolite membrane is usually 1 to 300 torr, preferably 5 to 150 torr, more preferably 30 to 1 torr.
00 torr.

[0033]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. In the following examples, the following materials were used.

(1) Porous alumina carrier: Ceramic filter manufactured by NGK Insulators, Ltd. (nominal “0.1 μm ceramic filter” in which a 0.1 μm layer is laminated on a 2.0 μm layer), inner diameter 7 mm, outer diameter 11mm, length 10
0mm)

(2) Zirconia sol (acid type): "AZS-A" manufactured by Nippon Shokubai Co., Ltd., average particle size 0.1 μm, concentration 6% by weight

(3) Silica sol: “Seahoster KE-E12” manufactured by Nippon Shokubai Co., Ltd., average particle size 0.12 μm, concentration 20.5% by weight

(4) Zeolite particles: Pulverized MFI-type zeolite (average particle size: 0.1 to 0.5 μm)

(5) Zeolite precursor solution: A solution having a molar ratio (SiO ₂ / A ₂ O ₃ ) of 20 of a silicic acid raw material and an alumina raw material was prepared according to the following procedure using the solutions shown in the following table.

[0039]

TABLE 1 Solution _{A: H 2 O: 150.5g, NaCl} : 3.8g B _{solution: H 2 O: 64.5g, Na} 2 SiO 3: 5.9g, NaOH: 0.3g C solution: H ₂ O: 119.5g, _{H 2 SO 4: 1.7g, TPABr} : 1.3g, Al
₂ (SO ₄ ) ₂ : 1.0 g

After the solution B and the solution C were added to the solution A at the same rate, the pH was adjusted to 9.5 using H ₂ SO ₄ and NaOH, and the stirring was continued for about 30 minutes, A white zeolite precursor solution was obtained.

Example 1 A porous alumina carrier was immersed in a zirconia sol for 24 hours and then dried at 110 ° C. to obtain a zirconia-coated carrier. Next, the zirconia-coated carrier whose outer surface was moistened was rolled on the zeolite particles stored in the tray, and the zirconium-coated carrier was adhered to the outer surface of the zirconia-coated carrier. Then, the surface to which the zeolite particles were adhered was rubbed to uniformly rub the zeolite particles on the outer surface of the carrier, and the remaining zeolite particles were wiped off. The amount of the zeolite particles finally deposited on the outer surface of the zirconia-coated carrier by the above treatment was about 0.3 per one porous alumina carrier.
3 g.

Next, the inside of the zirconia-coated carrier coated with the zeolite particles is filled with quartz wool,
In a cc autoclave, the zeolite precursor solution was added, the temperature was raised from room temperature to 200 ° C. over 24 hours, and the hydrothermal reaction was carried out for 48 hours. The hydrothermal reaction is performed three times on the same carrier, and the deposition treatment of zeolite particles is performed as follows.
Performed each time the reaction was repeated.

Next, the zeolite membrane obtained above was taken out of the autoclave, washed with ion-exchanged water until chlorine ions could not be detected, and dried naturally. Thereafter, the temperature was raised from room temperature to 503 ° C. at a rate of 0.1 ° C./min, and calcined for 4 hours. Then, the temperature was lowered at a rate of 0.1 ° C./min and cooled to room temperature. This operation took about 7 days. Next, the calcined zeolite membrane was immersed in a 10% by weight aqueous NH ₄ Cl solution and ion-exchanged at 80 ° C. Ion exchange is 3
Repeated times. Then, the substrate was washed with ion-exchanged water until chlorine ions were no longer detected, and then dried naturally. X
As a result of investigating the crystal structure of the zeolite membrane by line diffraction, it was found to be of MFI type. Further, the pore size distribution of the zeolite membrane was measured by a mercury intrusion method and a nitrogen adsorption method. FIG. 1 shows the measurement results. As is clear from FIG. 1, no crack exists.

Example 2 An MFI zeolite membrane was obtained in the same manner as in Example 1, except that silica sol was used instead of zirconia sol.

Comparative Example 1 The procedure of Example 1 was repeated, except that the treatment of zirconia coating and zeolite particle deposition was omitted, and the heating and cooling rates in the firing step were changed to about 1 to 10 ° C./min.
The same operation as described above was performed to obtain an MFI-type zeolite membrane.

Example 3 Using the cylindrical zeolite membrane obtained in Example 1, an olefin was produced by a dimerization dehydration reaction of methyl alcohol. The reaction is carried out by disposing a zeolite membrane in the internal space of a tubular reactor provided with a heater, and introducing a carrier gas inlet (A) into a space (external space of the zeolite membrane) between the tubular reactor and the zeolite membrane. And a reaction gas inlet, a carrier gas inlet (B) that communicates with the inner space of the zeolite membrane, and an extra-membrane product outlet that communicates with the outer space of the zeolite membrane and the inner space of the zeolite membrane. The reaction was carried out using a reactor provided with a conducting product outlet in the membrane.

The pressure inside and outside of the zeolite membrane was adjusted to a negative pressure to adjust the differential pressure between the inside and outside to 30 torr, and methyl alcohol vapor was supplied from the reaction gas inlet, and nitrogen gas was supplied from the carrier gas inlets (A) and (B). Supplied. Then, the vapor of methyl alcohol was allowed to pass through the zeolite membrane. Then, each product was extracted from the out-membrane product outlet and the in-membrane product outlet. The reaction conditions are shown in Table 2, and the composition of the product is shown in Table 3.

[0048]

Table 2 Differential pressure: 30 torr Reaction temperature: 400 ° C. Reaction time: 1 hour Residence time: 8.35 × 10 ⁻³ (Kg · mol · h ⁻¹ ) (residence time = net zeolite membrane on porous carrier) 40m
g / Methyl alcohol flow rate)

[0049]

[Table 3]

Example 4 An olefin was produced in the same manner as in Example 3 except that the differential pressure and the residence time were changed as shown in Table 4. Table 5 shows the composition of the product.

[0051]

Table 4 Differential pressure: 100 torr Reaction temperature: 400 ° C. Reaction time: 1 hour Residence time: 1.19 × 10 ⁻² (Kg · mol · h ⁻¹ ) (residence time = net zeolite membrane on porous carrier) 40m
g / Methyl alcohol flow rate)

[0052]

[Table 5]

Example 5 An olefin was produced in the same manner as in Example 3 except that the differential pressure and the residence time were changed as shown in Table 6. Table 7 shows the composition of the product.

[0054]

[Table 6] Differential pressure: 5 torr Reaction temperature: 400 ° C Reaction time: 1 hour Residence time: 6.68 × 10 ^-3 (Kg · mol · h ^-1 ) (residence time = net zeolite membrane on porous carrier) 40m
g / Methyl alcohol flow rate)

[0055]

[Table 7]

Comparative Example 2 The procedure of Example 3 was repeated, except that the zeolite membrane obtained in Comparative Example 1 was used, and the same reaction conditions as in Example 5 were employed. Was manufactured. Table 8 shows the composition of the product.

[0057]

[Table 8]

As is evident from the results of Examples 3 to 5 and Comparative Example 2, the zeolite membrane of the present invention has a higher catalytic performance (conversion and selectivity) in alcohol dimerization and dehydration than the comparative example. Excellent). In addition, the olefin concentration inside the zeolite membrane is high, that is, the olefin generated simultaneously with the dimerization dehydration reaction can be separated. In addition, since methyl alcohol can be used by recycling, there is no problem even if it is generated inside the film.

On the other hand, when the zeolite membrane of Comparative Example 1 was used, the permeation rate of the zeolite membrane was high, so that dimethyl ether passed through the membrane before being converted to olefin, so that the olefin formation reaction proceeded sufficiently. do not do.
This is because the zeolite membrane of Comparative Example 1 has cracks. Further, since the amount of paraffin relative to the olefin is large and by-products such as aromatics are generated inside the membrane, selective separation of the olefin is impossible.

[0060]

According to the present invention described above, a novel zeolite membrane having high thermal stability and mechanical strength, excellent molecular sieve ability and excellent catalytic performance in dimerization and dehydration of alcohol, a method for producing the same, and a method for producing the same. A method for producing an olefin using a zeolite membrane is provided, and the industrial value of the present invention is great.

[Brief description of the drawings]

FIG. 1 is a graph showing the pore size distribution of the zeolite membrane obtained in Example 1.

Claims (9)

[Claims] 1. A zeolite membrane formed by forming a zeolite membrane on the surface of a porous metal oxide carrier in which pores on the surface are filled with particles of metal oxide or metal nitride. 2. A zeolite membrane comprising a metal oxide or metal nitride particle layer and a zeolite membrane sequentially laminated on a surface of a porous metal oxide carrier. 3. The zeolite membrane according to claim 2, wherein the metal oxide or metal nitride particle layer forms a denser layer than the porous metal oxide carrier. 4. After coating the surface of the porous metal oxide carrier with metal oxide particles or metal nitride particles in an amount capable of filling at least the pores of the surface, the coated surface is used for forming a zeolite film. A method for producing a zeolite membrane, which comprises applying a seed crystal and then forming a zeolite membrane on the surface on which the seed crystal has been applied. 5. The surface coating of the porous metal oxide carrier with metal oxide particles or metal nitride particles is performed using a gel of metal oxide particles or metal nitride particles dispersed with a surfactant. A method for producing a zeolite membrane according to claim 4. 6. The method for producing a zeolite membrane according to claim 5, wherein the seed crystals for forming the zeolite membrane are zeolite particles or a zeolite precursor solution. 7. The zeolite precursor solution has a molar ratio (SiO ₂ / Al ₂ O ₃ ) of silica raw material to alumina raw material of 20-4.
7. The method for producing a zeolite membrane according to claim 6, wherein the aqueous medium solution is 0. 8. The method for producing a zeolite membrane according to claim 4, wherein the zeolite membrane is formed by a hydrothermal reaction of a zeolite precursor solution. 9. A method for producing an olefin by a dimerization and dehydration reaction of alcohol using a zeolite membrane, wherein the zeolite membrane according to claim 1 or the method according to claim 4 to 8. A method for producing an olefin using a zeolite membrane, comprising separating an olefin formed simultaneously with the dimerization dehydration reaction using the zeolite membrane obtained in the above step.