JP5895705B2 - Propylene production method - Google Patents

Description

  The present invention relates to a method for producing propylene from a raw material containing methanol and / or dimethyl ether.

  As a method for producing propylene, steam cracking of naphtha and fluid catalytic cracking of vacuum gas oil have been conventionally performed. In recent years, metathesis reaction using ethylene and 2-butene as raw materials and methanol and / or dimethyl ether are used. An MTO (methanol to olefin) process as a raw material is known.

For example, in Patent Document 1, propylene is produced from methanol using a catalyst having ZSM-5, which is an MFI type aluminosilicate, as an active ingredient.
In Patent Document 2, propylene is produced from methanol using a catalyst having SAPO-34, which is a CHA-type silicoaluminophosphate, as an active ingredient.

  However, in these currently known MTO processes, ethylene and propylene are the main products, and ethylene is produced in the same amount as propylene.

  On the other hand, as a method for producing ethylene, steam cracking (hereinafter referred to as ethane cracking) using ethane contained in natural gas as a raw material is known. Due to the recent decline in natural gas prices, ethylene production costs for ethane tank racking have significantly decreased compared to naphtha steam cracking, and ethylene production by ethane tank racking has rapidly expanded. However, unlike naphtha steam cracking, ethane cracking produces few hydrocarbons with 3 or more carbon atoms such as propylene, butadiene, butene, etc., and therefore lacks 3 or more hydrocarbons, especially propylene and butadiene. This situation is becoming apparent.

  Therefore, there is a demand for a production method capable of selectively producing an olefin having 3 or more carbon atoms such as propylene by the MTO method and suppressing the amount of ethylene produced. In addition, since butene is a useful substance used as a raw material of butadiene, it is particularly important to efficiently produce propylene and butene.

USP 4,148,835 JP 59-084829 A

  An object of the present invention is to provide a method for efficiently producing propylene by bringing a raw material containing methanol and / or dimethyl ether into contact with a catalyst.

  As a result of intensive studies to solve the above problems, the present inventors have found that propylene can be efficiently produced by using a zeolite having a specific structure as a catalytically active component. It came.

That is, the first gist of the present invention is a method for producing propylene by bringing a raw material containing methanol and / or dimethyl ether into contact with a catalyst, wherein the catalyst is a code defined by the International Zeolite Association (IZA). in look-containing zeolite is CON structure as active ingredient, the zeolite lies boron, the method of manufacturing propylene characterized by gallium and either one or more free Mukoto selected from aluminum, the.

According to the present invention, propylene can be produced in a high yield by using a catalyst containing methanol and / or dimethyl ether as a raw material and a zeolite having a CON-type structure as an active component. Can be produced in high yield.
Further, according to the present invention, it is possible to suppress the by-production of ethylene during the production of propylene, and further, it is possible to obtain an effect that the catalyst coking due to the reaction is small and the catalyst life is long.

2 represents an XRD pattern of a CON-type zeolite powder (Preparation Example 1) used in Example 1. 2 represents an XRD pattern of a CON-type zeolite powder (Preparation Example 2) used in Example 2. 3 represents an XRD pattern of a CON-type zeolite powder (Preparation Example 3) used in Example 3. 3 represents an XRD pattern of a CON-type zeolite powder (Preparation Example 4) used in Example 4.

Below, the typical aspect for implementing this invention is demonstrated concretely, However, This invention is not limited to the following aspects, unless the summary is exceeded.

[catalyst]
In the present invention, a catalyst containing a zeolite having a CON-type structure (hereinafter referred to as “CON-type zeolite”) as a catalytic active component is used as a catalyst, as defined by the International Zeolite Association (IZA).

  The CON-type zeolite is a zeolite having a three-dimensional pore structure having two 12-membered ring structures and one 10-membered ring structure intersecting as structural units. This CON-type zeolite having a 12-membered ring structure is more effective in the pores of the reaction product than the CHA-type zeolite composed only of an 8-membered ring structure or the MFI-type zeolite composed of only a 10-membered ring structure. Diffusion is advantageous and the catalyst has excellent selectivity for olefins having 3 or more carbon atoms. Also, as described above, the CON-type zeolite has a structure in which a 12-membered ring structure and a 10-membered ring structure intersect zigzag, and since the pores in three directions do not intersect at one place, the space of the intersection is small, and depending on the reaction It is considered that coke is hardly generated, and it is considered difficult to cause a significant decrease in reaction activity, and there is an advantage that the catalyst life is long.

  The CON type zeolite used in the present invention is not particularly limited, but is preferably a crystalline metallosilicate. The element constituting the metallosilicate is not particularly limited. For example, aluminum (Al), boron (B), titanium (Ti), vanadium (V), iron (Fe), zinc (Zn), gallium (Ga) ), Germanium (Ge), zirconium (Zr), and tin (Sn).

  Specifically, crystalline aluminosilicate containing Al as a constituent element and crystalline gallosilicate containing Ga are preferable. These zeolites are excellent in catalytic activity because Al and Ga in the zeolite skeleton serve as acid sites and act as active sites for catalytic reactions.

  Further, the CON-type zeolite used in the present invention may contain B as a constituent element because it is easily obtained by adding a boron compound to a raw material gel described later. Examples thereof include crystalline boroaluminosilicate containing Al and B as constituent elements, and crystalline galloborosilicate containing constituent elements Ga and B.

  The CON type zeolite is preferably a metallosilicate containing B, and examples thereof include boroaluminosilicate and galloborosilicate. These are suitable for the present invention because the total yield of propylene and butene is high and the ethylene selectivity is low. Moreover, the thing containing Ga is preferable also at the point by which the byproduct of an aromatic compound is hardly seen.

  In the case of the crystalline aluminosilicate and the crystalline gallosilicate, the ratio of the constituent elements is not particularly limited, but the Si / Al molar ratio or Si / Ga molar ratio is usually 5 or more, preferably It is 10 or more, more preferably 20 or more, still more preferably 25 or more, particularly preferably 50 or more, particularly preferably 100 or more, and usually 5000 or less, preferably 1000 or less, more preferably 500 or less.

  For the production of these crystalline aluminosilicates and crystalline gallosilicates, after synthesizing crystalline borosilicate containing only B as a constituent element, B in the zeolite skeleton is removed, and a metal such as Al or Ga is removed at the removed portion. A method of introducing (post processing) may be employed. B in the zeolite framework can be removed by acid treatment or steam treatment.

  In the case of the crystalline boroaluminosilicate and the crystalline galloborosilicate, the ratio of the constituent elements is not particularly limited. However, as with the crystalline aluminosilicate and the crystalline gallosilicate, the Si / Al mole thereof is not limited. The ratio or Si / Ga molar ratio is usually 5 or more, preferably 10 or more, more preferably 20 or more, further preferably 25 or more, particularly preferably 50 or more, particularly preferably 100 or more, and usually 5000 or less, preferably Is 1000 or less, more preferably 500 or less. The Si / B molar ratio is usually 0.1 or more, preferably 1 or more, more preferably 5 or more, further preferably 10 or more, particularly preferably 15 or more, and usually 5000 or less, preferably 1000 or less, Preferably it is 100 or less.

  The ion exchange site of the CON-type zeolite used in the present invention is not particularly limited, and may be H-type or exchanged with metal ions. Here, the metal ions are specifically alkali metal ions, alkaline earth metal ions, and the like.

The BET specific surface area of the CON-type zeolite used in the present invention is not particularly limited, and is usually 200 m ² / g or more, preferably 250 m ² / g or more, more preferably 300 m ² / g or more. It is 2000 m ² / g or less, preferably 1500 m ² / g or less, more preferably 1000 m ² / g or less.
Further, the pore volume of the CON-type zeolite used in the present invention is not particularly limited, and is usually 0.1 ml / g or more, preferably 0.2 ml / g or more, usually 3 ml / g or less, Preferably it is 2 ml / g or less.

  CON-type zeolite is described in J. Org. Am. Chem. Soc. 117, 3766-3779 (1995), and those synthesized by known methods can be used.

  A CON-type zeolite can generally be prepared by a hydrothermal synthesis method. For example, a boron source, an aluminum source, a gallium source, and a silica source are added to water to form a uniform gel, and a structure directing agent, preferably N, N, N-trimethyl-(-)-cis-miltanylammonium Hydroxide is added and stirred, and the obtained raw material gel is crystallized by being kept at 120 to 200 ° C. in a pressure heating container. During crystallization, a seed crystal may be added as necessary, and in terms of manufacturability, adding a seed crystal is preferable in terms of improving operability. Next, the crystallized raw material gel is filtered and washed, and then the solid content is dried at 100 to 200 ° C., and then calcined at 400 to 900 ° C. to obtain zeolite powder.

  Here, as the boron source, one or more of boric acid, sodium borate, boron oxide and the like can be used. As the aluminum source, one or more of aluminum sulfate, aluminum nitrate, pseudoboehmite, aluminum alkoxide, aluminum hydroxide, alumina sol, sodium aluminate and the like can be used. As the gallium source, one or more of gallium nitrate, gallium sulfate, gallium phosphate, gallium chloride, gallium bromide, gallium hydroxide and the like can be used. As the silica source, one or more of silicates such as fumed silica, silica sol, silica gel, silicon dioxide, water glass, silicon alkoxides such as tetraethoxyorthosilicate and tetramethoxysilane, silicon halides and the like are used. be able to.

  The CON-type zeolite used in the present invention can adjust the amount of metal contained by adjusting the amount of constituent elements (Al, Ga, B, etc.) during synthesis. Moreover, what adjusted some content by removing a part of structural element by steaming, acid treatment, etc. can also be used.

  The CON-type zeolite may be used as it is as a catalyst in the present invention for the reaction, or may be used for the reaction by granulating or molding using a substance or a binder inert to the reaction. Examples of the substance or binder inert to the reaction include alumina or alumina sol, silica, silica gel, silicate, quartz, and a mixture thereof. Among these, silicate is preferable in that a strong molded body can be obtained as an industrial catalyst. Mixing with these substances is effective for reducing the cost of the entire catalyst and acting as a heat sink for heat shielding during catalyst regeneration. It is also effective for increasing the density of the catalyst and increasing the catalyst strength. .

  The particle size of the catalyst in the present invention varies depending on the conditions during synthesis, but is usually 0.01 to 500 μm, preferably 0.1 to 10 μm, as an average particle size. When the particle size of the catalyst is too large, the surface area showing the catalytic activity becomes small, and when it is too small, the handleability tends to be inferior, which is not preferable in either case. This average particle diameter can be determined by laser diffraction measurement. However, since the laser diffraction method cannot measure 0.1 μm or less, when the result measured by the laser diffraction method is 0.1 μm or less, the value obtained by a scanning electron microscope (SEM) is the average particle size referred to in the present invention. The diameter.

[Methanol, dimethyl ether]
Next, methanol and dimethyl ether used as reaction raw materials in the present invention will be described.
The origin of production of methanol and / or dimethyl ether used as a reaction raw material is not particularly limited. For example, one obtained by hydrogenation reaction of coal and natural gas, and by-product hydrogen / CO mixed gas in the steel industry, one obtained by reforming reaction of plant-derived alcohols, one obtained by fermentation method And those obtained from organic materials such as recycled plastic and municipal waste. At this time, a state in which compounds other than methanol and dimethyl ether resulting from each production method are arbitrarily mixed may be used as it is, or a purified one may be used.
In addition, as a reaction raw material, only methanol may be used, only dimethyl ether may be used, and these may be mixed and used. When methanol and dimethyl ether are mixed and used, the mixing ratio is not limited.

[Reaction operations and conditions]
Hereinafter, the operation and conditions of the propylene production reaction of the present invention using the above-described catalyst and reaction raw materials will be described.

<Reactor>
The reaction mode in the production method of the present invention is not particularly limited as long as the methanol and / or dimethyl ether feedstock is in a gas phase in the reaction zone, and is well-known using a fluidized bed reactor, moving bed reactor or fixed bed reactor. The gas phase reaction process can be applied. In the case of a fixed bed reactor, it is particularly advantageous in terms of equipment costs including incidental equipment, catalyst costs, and operation management.
Further, it can be carried out in any form of batch, semi-continuous or continuous, but is preferably carried out continuously, and the method may be a method using a single reactor, or in series or in parallel. A method using a plurality of arranged reactors may also be used.

  In addition, when packing the above-mentioned catalyst into the fluidized bed reactor, in order to keep the temperature distribution of the catalyst layer small, particulates inert to the reaction such as quartz sand, alumina, silica, silica-alumina, etc. are mixed with the catalyst. And may be filled. In this case, there is no particular limitation on the amount of granular material inactive to the reaction such as quartz sand. In addition, it is preferable that this granular material is a particle size comparable as a catalyst from the surface of uniform mixing property with a catalyst.

  Further, the reaction substrate (reaction raw material) may be divided and supplied to the reactor for the purpose of dispersing heat generated by the reaction.

The catalyst used in the present invention has less coking than a conventional catalyst and the rate of catalyst deterioration is slow. However, when a long-term operation is performed, for example, when continuous operation is performed for one year or more, catalyst regeneration is performed during the operation. Need to do.
Thus, for example, when selecting a fixed bed reactor, it is desirable to install at least two reactors and operate while switching between reaction and regeneration. As the form of the fixed bed reactor, a multitubular reactor or an adiabatic reactor is selected.
On the other hand, when selecting a fluidized bed reactor, it is preferable to carry out the reaction while continuously feeding the catalyst to the regeneration tank and continuously returning the catalyst regenerated in the regeneration tank to the reactor.

  Here, examples of the regeneration operation of the catalyst include one that regenerates the catalyst introduced from the reactor by treating it with nitrogen gas containing oxygen, water vapor, hydrogen, or the like.

<Substrate concentration>
There is no particular limitation on the total concentration of methanol and dimethyl ether (substrate concentration) in all feed components fed to the reactor, but the sum of methanol and dimethyl ether is preferably 90 mol% or less in all feed components. More preferably, it is 10 mol% or more and 70 mol% or less. If the substrate concentration is too high, aromatic compounds and paraffins are prominently produced and the propylene selectivity tends to decrease. On the other hand, if the substrate concentration is too low, the reaction rate becomes slow, so a large amount of catalyst is required, and the cost for purifying the reactor, the product, and the reaction equipment increases, which is not economical.
Therefore, it is preferable to dilute the reaction substrate with a diluent described below as necessary so as to obtain such a preferable substrate concentration.

<Diluent>
In the reactor, in addition to methanol and / or dimethyl ether, hydrocarbons such as helium, argon, nitrogen, carbon monoxide, carbon dioxide, hydrogen, water, paraffins, methane, aromatic compounds, and those A gas inert to the reaction, such as a mixture of the above, can be present, but among them, it is preferable that helium, nitrogen, and water (water vapor) coexist because of good separation.
As such a diluent, impurities contained in the reaction raw material may be used as they are, or a separately prepared diluent may be mixed with the reaction raw material and used.
The diluent may be mixed with the reaction raw material before entering the reactor, or may be supplied to the reactor separately from the reaction raw material.

<Weight space velocity>
The weight space velocity referred to here is the flow rate of methanol and / or dimethyl ether, which is a reaction raw material, per weight of the catalyst (catalytic active component), and the weight of the catalyst is the amount used for granulation / molding of the catalyst. This is the weight of the catalytically active component that does not contain the active component or binder. The flow rate is the total flow rate (weight / hour) of methanol and / or dimethyl ether.

The weight space velocity is usually about 0.01 hour- ¹ or more, preferably about 0.05 hour- ¹ or more, more preferably about 0.1 hour- ¹ or more, usually about 500 hour- ¹ or less, preferably About 200 hours- ¹ or less. If the weight space velocity is too high, the conversion rate of the raw materials methanol and / or dimethyl ether is low, and sufficient propylene selectivity cannot be obtained. On the other hand, if the weight space velocity is too low, the amount of catalyst necessary to obtain a certain production amount increases, the reactor becomes too large, and undesirable by-products such as aromatic compounds and paraffin are produced, and propylene is produced. Since the selectivity is lowered, it is not preferable.

<Reaction temperature>
The lower limit of the reaction temperature is usually about 200 ° C. or higher, preferably 250 ° C. or higher, more preferably 300 ° C. or higher. The upper limit of the reaction temperature is usually 750 ° C. or lower, preferably 700 ° C. or lower. If the reaction temperature is too low, the reaction rate tends to be low, a large amount of unreacted raw material tends to remain, and the yield of propylene also decreases. On the other hand, if the reaction temperature is too high, it is difficult to obtain a stable activity of the catalyst, and the yield of propylene is significantly reduced. Here, the reaction temperature refers to the temperature at the inlet of the catalyst layer.

<Reaction pressure>
The upper limit of the reaction pressure is usually 5 MPa or less (absolute pressure, the same applies hereinafter), preferably 2 MPa or less, more preferably 1 MPa or less, and particularly preferably 0.7 MPa or less. The lower limit of the reaction pressure is not particularly limited, but is usually 0.1 kPa or more, preferably 7 kPa or more, more preferably 50 kPa or more. If the reaction pressure is too high, the amount of undesired by-products such as paraffins and aromatic compounds increases, and the yield of propylene tends to decrease. If the reaction pressure is too low, the reaction rate tends to be slow.

<Reaction product>
As the reactor outlet gas (reactor effluent), a mixed gas containing the reaction product propylene, a by-product and a diluent is obtained. The propylene concentration in the mixed gas is usually 5 to 95% by weight.
Depending on the reaction conditions, methanol and / or dimethyl ether are included as unreacted raw materials in the reaction product, but it is preferable to carry out the reaction under such reaction conditions that the conversion of methanol and / or dimethyl ether is 100%. Thereby, separation of the reaction product and the unreacted raw material is easy and preferably unnecessary.
By-products include ethylene, olefins having 4 or more carbon atoms, paraffins, aromatic compounds, and water.

<Product separation>
The mixed gas containing propylene, unreacted raw materials, by-products and diluent as reaction product outlet gas is introduced into a known separation / purification facility, and is collected and purified according to each component. What is necessary is just to process recycling and discharge.

  One aspect of this separation / purification method includes a step of cooling and compressing the gas at the outlet of the reactor to remove most of the condensed moisture, and a hydrocarbon fluid containing a portion of moisture after removing the moisture. A method comprising a step of drying the olefin and paraffin by distillation using a molecular sieve or the like and then purifying each olefin and paraffin by distillation. In the above method, the compressed hydrocarbon fluid may be supplied to one distillation column. However, a multistage compressor is installed to roughly separate hydrocarbons that are easily condensed and hydrocarbons that are difficult to condense, and separate them. Distillation may be performed by supplying to the distillation column.

  Components other than propylene (olefin, paraffin, etc.), especially part or all of hydrocarbons with 4 or more carbon atoms, are recycled by mixing with the reaction raw materials after being separated and purified as described above, or by directly supplying them to the reactor. It is preferable to do this. In addition, among the by-products, components inactive to the reaction can be reused as a diluent.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

  In the following preparation examples, the X-ray diffraction (XRD) pattern of the synthesized zeolite was obtained by using RINT Ultimate III manufactured by Rigaku Corporation. The X-ray source is CuKα (X-ray output: 40 kV, 20 mA), the reading width is 0.02 °, and the scanning speed is 2.0 ° / min. The composition of the synthesized zeolite was measured by ICP analysis. For measurement, Shimadzu ICPE-9000 was used.

[Preparation Example 1: Synthesis of CON-type boroaluminosilicate]
0.92 g of 0.5 M sodium hydroxide aqueous solution, 2.1 g of 0.75 M N, N, N-trimethyl-(-)-cis-miltanyl ammonium hydroxide (hereinafter abbreviated as “TMMAOH”) aqueous solution and water 7.1 g was mixed, 0.011 g of boric acid and 0.015 g of aluminum sulfate were added and stirred, and then 0.54 g of fumed silica (manufactured by Cab-O-Sil M-7D CABOT) was added as a silica source. And stirred well. Furthermore, 0.011 g of BEA type borosilicate was added as a seed crystal and stirred to prepare a reaction mixture (hereinafter sometimes referred to as “raw material gel”).
The obtained raw material gel was charged into an autoclave and heated at 170 ° C. for 21 days in a state of standing still. The product was filtered, washed with water, and dried at 100 ° C. overnight. After drying, it was calcined at 600 ° C. for 6 hours in an air atmosphere to obtain 0.42 g of sodium-type zeolite powder (boroaluminosilicate).
The obtained powder was subjected to ion exchange in a 2N aqueous ammonium nitrate solution at 80 ° C. for 1 hour, and then filtered. The filtered powder was again ion-exchanged in a 2N aqueous ammonium nitrate solution at 80 ° C. for 1 hour, and then filtered and dried to obtain an ammonium-type zeolite. Thereafter, it was calcined at 600 ° C. in an air atmosphere to obtain a proton type zeolite.
The XRD pattern of the obtained powder is shown in FIG. From FIG. 1, it was confirmed that the product was a zeolite having a CON type structure.
Table 1 shows the composition of the raw material gel of Preparation Example 1 and the composition of the synthesized zeolite.

[Preparation Example 2: Synthesis of CON-type Galoborosilicate]
The same method as in Preparation Example 1 except that the amount of boric acid was changed to 0.022 g and 0.020 g of gallium nitrate (III) · n hydrate (n = 7-9) was added instead of aluminum sulfate. By synthesis, 0.48 g of sodium-type zeolite (galloborosilicate) was obtained. Subsequent ion exchange and calcination were carried out in the same manner as in Preparation Example 1 to obtain proton type zeolite.
The XRD pattern of the obtained powder is shown in FIG. From FIG. 2, it was confirmed that the product was a zeolite having a CON-type structure.
The composition of the raw material gel of Preparation Example 2 and the composition of the synthesized zeolite are shown in Table 1.

[Preparation Example 3: Synthesis of CON-type aluminosilicate]
After mixing 3.6 g of 0.5 M aqueous sodium hydroxide solution, 4.2 g of 0.75 M TMAOH aqueous solution and 12.4 g of water, 0.044 g of boric acid was added thereto and stirred, and then fumed silica (Cab (-O-Sil M-7D made by CABOT) 1.08 g was added and sufficiently stirred. Further, 0.022 g of BEA-type borosilicate was added as a seed crystal and stirred to prepare a reaction mixture (hereinafter sometimes referred to as “raw material gel”).
The obtained raw material gel was charged into an autoclave and heated at 170 ° C. for 21 days in a state of standing still. The product was filtered, washed with water, and dried at 100 ° C. overnight. After drying, it was calcined at 600 ° C. for 6 hours in an air atmosphere to obtain 0.82 g of sodium-type zeolite powder (borosilicate).
The following operation (post treatment) was performed for the purpose of removing boron (deboronization) from the zeolite skeleton of the resulting borosilicate and replacing it with aluminum.
The obtained borosilicate 0.5g was added to 0.01M hydrochloric acid aqueous solution 50g, and it stirred under reflux at 100 degreeC for 24 hours. Thereafter, the zeolite was filtered and washed with water, and then dried at 100 ° C. overnight to obtain proton type zeolite powder (silicate). The total amount of the obtained powder was added to 25 g of an aqueous solution in which 1.5 g of aluminum nitrate nonahydrate was dissolved, and the mixture was stirred at 100 ° C. for 12 hours under reflux. Thereafter, the zeolite was filtered, washed with water, and then dried at 100 ° C. overnight to obtain 0.43 g of proton type zeolite powder (aluminosilicate).
The XRD pattern of the obtained powder is shown in FIG. From FIG. 3, it was confirmed that the product was a zeolite having a CON type structure.
Table 1 shows the composition of the raw material gel of Preparation Example 3, the composition of the post treatment, and the composition of the synthesized zeolite.

[Preparation Example 4: Synthesis of CON-type aluminosilicate]
The synthesis was performed in the same manner as in Preparation Example 3 except that the amount of aluminum nitrate nonahydrate was changed to 0.31 g to obtain 0.40 g of proton type zeolite powder (aluminosilicate).
The XRD pattern of the obtained powder is shown in FIG. From FIG. 4, it was confirmed that the product was a zeolite having a CON type structure.
Table 1 shows the composition of the raw material gel of Preparation Example 4, the composition of the post treatment, and the composition of the synthesized zeolite.

[Examples 1 to 4]
Propylene was produced using the CON type zeolite catalyst obtained in Preparation Examples 1 to 4.
For the reaction, an atmospheric pressure fixed bed flow reactor was used, and 50 mg of zeolite having a CON-type structure obtained in Preparation Examples 1 to 4 was packed in a quartz reaction tube having an inner diameter of 3 mm. A mixed gas of 12.5 mol% of methanol and 87.5 mol% of helium was supplied to the reactor so that the weight space velocity of methanol was 0.29 hours ⁻¹ , at 500 ° C. and 0.1 MPa (absolute pressure). Reaction was performed. One hour after the start of the reaction, the product was analyzed by gas chromatography. The results are shown in Table 2.

[Comparative Example 1]
The reaction was carried out in the same manner as in Examples 1 to 4, except that zeolite having an MFI type structure (JRC-Z5-90H (1), reference catalyst of Zeolite Society) was used as the catalyst. The results are shown in Table 2.

  From the results of Examples 1 to 4, the propylene selectivity when using the CON-type zeolite and the total selectivity of propylene and butene were significantly higher than when using the MFI-type zeolite of Comparative Example 1, It can be seen that the ethylene selectivity is low. Compared to MFI-type zeolite consisting only of a 10-membered ring structure, the CON-type zeolite has a 12-membered ring structure, which facilitates diffusion of the reaction product in the pores, and selection of olefins having 3 or more carbon atoms. It is presumed to be due to the improvement in performance.

Claims (1)

A method for producing propylene by bringing a raw material containing methanol and / or dimethyl ether into contact with a catalyst, wherein the catalyst comprises a zeolite having a CON-type structure as an active ingredient according to a code defined by the International Zeolite Association (IZA). unrealized, the zeolite, boron, method for producing propylene according to claim any one or more free Mukoto selected from gallium and aluminum.

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