KR20150129186A - Zeolite catalysts for converting oxygenates to propylene and method for preparing thereof - Google Patents

Abstract

The present invention relates to a zeolite catalyst having a hollow micropore, for manufacturing propylene from oxygenates such as methanol or dimethyl ether, and to a manufacturing method thereof. According to the present invention, the zeolite catalyst can have high selectivity of propylene, long catalyst durability, and excellent hydrothermal stability, in the case of being used as a catalyst during a reaction of manufacturing propylene, by having a hollow micropore inside a crystal and reforming an acid site as phosphorus (P) at the same time.

Description

TECHNICAL FIELD [0001] The present invention relates to a zeolite catalyst for producing propylene from an oxygenate and a method for producing the zeolite catalyst,

The present invention relates to a zeolite catalyst having hollow pores for the production of propylene from oxygenates such as methanol or dimethylether, and a process for its preparation.

Generally, in petrochemistry, propylene is mainly obtained as a by-product of pyrolysis of naphtha and fluidized catalytic cracking (FCC), and recently it is also obtained from non-petrochemical raw materials. For example, propane dehydrogenation (PDH) or methanol-based processes are typical examples of propane. The methanol-based processes include methanol-to-olefins (MTO) from methanol and methanol-to-propylene (MTP) from methanol.

The MTP process has been developed by Lurgi to commercialize coal-based methanol as a raw material in China. This process is known to use a fixed bed reactor and ZSM-5 zeolite as a catalyst.

Generally, zeolite is crystalline aluminosilicate and has micropore size of molecular size (0.2 ~ 2nm). It can be used for various applications (catalyst, adsorbent, ion exchanger, absorber, etc.) by pore characteristics and ion exchange function. Widely used. Particularly, when these zeolites are used as catalysts or catalyst supports, the pore characteristics greatly influence the catalyst performance. In a zeolite having fine pores, when a molecule diffuses-moves and reacts in a pore, the diffusion occurs very slowly, so that the reaction may be slowed, or a problem such as an increase in side reaction or shortening of the catalyst life may occur. In order to solve this problem, the size of the zeolite crystals is made small to increase the outer surface area, thereby shortening the moving distance in the zeolite crystals, or making the hollow in the zeolite crystals, so that the molecular movement occurs through the hollow and the reaction occurs in the fine pores , Attempts have been made to overcome the drawbacks of the microporous zeolite.

If the micropores and hollows are present at the same time as the case of the micropores alone, the catalyst performance is greatly improved, and the catalyst life is prolonged or the selectivity is improved. In the case of only fine pores, the length of the reactant or product passing through the zeolite pores is long, causing side reactions, shortening the catalyst life, and slowing the diffusion rate of the molecules by producing coke. On the other hand, in the case of zeolites with hollow pores, the reaction takes place mainly in the micropores, but the movement of the materials (reactants or products) takes place rapidly through the micropores adjacent to the micropores. As a result, the retention time in the fine pores is short, so that the selectivity of the catalyst is excellent, and the catalyst has a long catalyst life with little coke formation. The zeolite composed only of micropore has a characteristic of mainly participating in the reaction only on the surface of the zeolite crystal, but the zeolite having the hollow pore has a high utilization degree by participating in the catalytic reaction in the whole crystal.

The preparation of zeolites with hollow pores has been attempted in a variety of ways.

First, a material composed of silica (SiO ₂ ) or silica-alumina (SiO ₂ -Al ₂ O ₃ ) having a regular hollow but having an inner wall as an amorphous material is synthesized first, and then an organic amine- (2001), pp. 683-687, and U.S. Patent No. 6,104,308, which is incorporated herein by reference in its entirety), and then converting the inner wall of the amorphous into the crystalline zeolite by hydrothermal synthesis (Chemistry of Materials 13 6,669,924).

In the second method, a zeolite seed is impregnated with an amorphous material having a hollow in place of the organic amine predominant form, and then a hollow zeolite is produced by nitriding zeolite by hydrothermal synthesis in the same manner as in the first method (Angewandte Chemie International, 41 (2002), P1036-1040).

The third method is a method of preparing a hollow zeolite by mixing an organic material as a main body with a source necessary for the synthesis of zeolite such as Al and Si and hydrothermally synthesizing the organic material (European Patent Registration No. 1,882,676).

The fourth is to use a surfactant having an organosilane group and to produce a hollow zeolite by bonding a silane group to a zeolite surface and a long chain hydrocarbon attached to the silane group to contribute to the formation of hollow No. 10-727288).

Fifth, a hollow-type zeolite is synthesized by hydrothermal synthesis after mixing a template such as activated carbon with a zeolite synthetic gel for hollow formation (U.S. Patent Publication No. 2001-0003117).

The sixth method is to introduce a hollow into the zeolite crystals by dealumination or desilication of the synthesized zeolite (U.S. Patent No. 5,069,890, European Patent Registration No. 0,528,494, 6,017,508).

On the other hand, the zeolite having the above-mentioned conventional hollow pores has been generally used for a hydrogenation catalyst, a catalyst for producing aromatics or the like, or merely focuses on a method for producing hollow pores, Have not yet been reported.

Under these circumstances, the present inventors have found that when a zeolite having hollow pores in its crystal and modified with phosphorus (P) at its acid site is used in the production of propylene, it can have high selectivity for propylene, long catalyst life and excellent hydrothermal stability Thereby completing the present invention.

A first aspect of the present invention is a catalyst comprising a zeolite having a mesopore in the crystal and a micropore formed in the hollow pore, wherein the hollow pore has a diameter of 2 nm or more, a pore volume of 0.1 cc / g Wherein the average diameter of all the pores including the hollow pores and the fine pores is 3 nm or more, the total BET specific surface area of the zeolite is 350 m ² / g or more, the density of the strong acid point of the zeolite is 0.04 to 0.3 mmol / g And the zeolite is modified with phosphorus (P) in its surface and pore interior. The zeolite catalyst for the production of propylene from oxygenates is provided.

A second aspect of the present invention is a method for producing a zeolite-containing slurry, comprising: a first step of heating a slurry containing zeolite having a Si / Al molar ratio in the skeleton of 80 or more to 40 占 폚 to 100 占 폚; A second step of adding a basic solution containing a water-soluble aluminum precursor or quaternary ammonium ions to the slurry of the first stage to form hollow pores in the zeolite; A third step of ion-exchanging the zeolite formed with the hollow pores in the second step with H ⁺ or NH4 ⁺ ; A fourth step of drying and firing the zeolite ion-exchanged in the third step; A fifth step of treating the dried and calcined zeolite with phosphorus (P) precursor in the fourth step; And a sixth step of firing the zeolite treated with the phosphorus (P) precursor in the fifth step. The zeolite catalyst for producing propylene from the oxygenate of the first aspect is prepared.

A third aspect of the present invention is a method for producing a zeolite comprising: a first step of heating a slurry containing zeolite having a Si / Al molar ratio in the skeleton of 80 or less to 40 to 100 캜; A second step of adding a basic solution to the slurry of the first step to form hollow pores in the zeolite; A third step of removing a part of aluminum in the zeolite framework by heating the zeolite formed with the hollow pores in the second step under steam; A fourth step of treating the steam-treated zeolite in the third step with an acid to remove the non-skeletal aluminum of the zeolite; A fifth step of treating the acid-treated zeolite with phosphorus (P) precursor in the fourth step; And a sixth step of firing the zeolite treated with the phosphorus (P) precursor in the fifth step. The zeolite catalyst for producing propylene from the oxygenate of the first aspect is prepared.

A fourth aspect of the present invention provides a method for producing propylene from an oxygenate under the zeolite catalyst produced by the zeolite catalyst of the first aspect, the method of the second or third aspect.

Hereinafter, the present invention will be described in detail.

Solid acid catalysts are catalytic materials with Bronsted and / or Lewis acid sites on the solid surface and are used in petrochemical industry in various processes such as catalytic cracking, isomerization, alkylation and the like. A representative example of the solid acid catalyst is a zeolite catalyst. The zeolite can generate acid sites because silicon (Si) and aluminum (Al) are bonded to each other with oxygen as a bridge. In the present invention, the zeolite may have an MFI, BTA or MOR structure, and further, a hollow pore is introduced.

Most of the catalysts for the production of propylene from conventional oxygenates have used mostly microporous zeolites. In the conversion of propylene oxide to propylene, saturated hydrocarbons, aromatics, or coke are thermodynamically more stable than propylene (i.e., precursors such as saturated hydrocarbons are intermediate products). Therefore, in order to further increase the selectivity of the intermediate product, propylene, the pore characteristics as well as the density of the strong acid point of the catalyst should be appropriately selected. However, the zeolite catalyst composed of only fine pores has a problem that the selectivity of products such as propylene is lowered and the catalyst deactivation due to the formation of coke is intensified because the length of the reactant or product passing through the fine pores is long. That is, the propylene produced in the fine pores is converted into saturated hydrocarbons, aromatics, or coke by reacting more slowly while passing through the fine micropores, so that the resulting propylene rapidly passes through the pores, It is necessary to prevent it. Accordingly, the present invention reduces the long diffusion distance of micropores by introducing mesopores into the zeolite crystals, thereby allowing the propylene produced in the micropores to quickly escape through the micropores (reduction in retention time in micropores ), And the selectivity of propylene was remarkably increased. At the same time, by escaping the pores before the propylene reacts further, the production of the coke as a catalyst deactivation material in the micropore can be reduced, and as a result, the catalyst life can be increased.

In one embodiment of the present invention, it was confirmed that the zeolite catalyst of the present invention having hollow pores and fine pores formed therein had much better catalytic properties than the zeolite catalyst having only micropores (Experimental Example 2).

Furthermore, when propylene is produced from the oxygen-containing compound, aluminum acting as an acid catalyst by the generated water escapes from the skeleton of the zeolite to permanently lose its activity as a solid acid. In order to solve the hydrothermal stability problem of such a zeolite catalyst, the present invention increased its hydrothermal stability by modifying the acid sites in its surface and pores to phosphorus (P).

In one embodiment of the present invention, the zeolite catalyst modified with phosphorus (P) of the present invention was found to have higher propylene selectivity and catalyst life than that of the zeolite catalyst of the present invention (Experimental Example 2).

As described above, the zeolite catalyst according to the present invention has hollow pores and is modified into phosphorus on the surface and inside of the pores, so that it has better catalytic performance and lifetime in the propylene production reaction than a zeolite catalyst having only micropores It is based on discovery.

The zeolite catalyst according to the present invention has hollow pores in the crystal and fine pores formed in the hollow pores.

In the zeolite of the present invention, the hollow pores have a medium pore diameter, and their sizes are not clearly defined. However, in IUPAC, it is generally recommended that pores having a diameter of 2 nm to 50 nm are referred to as hollow pores. In the present invention, the hollow pores are pores having a diameter of 2 nm or more and a pore volume of 0.1 cc / g or more in the zeolite skeleton. When the diameters and the pore volume are smaller than the above, hollow properties (for example, Generation, etc.) of the zeolite catalyst does not appear well, so that there is no significant difference in catalytic performance as compared with the conventional microporous zeolite catalyst. On the other hand, the average diameter of the hollow pores may be 50 nm or less, but is not particularly limited and may be within the range of general hollow pores referred to in the technical field. The average diameter and pore volume of the hollow pores can be calculated as the amount of nitrogen adsorbed at the nitrogen adsorption-desorption isotherm.

On the other hand, smaller micropores are formed inside the hollow pores. The micropores are smaller in diameter than the hollow micropores. Generally, in IUPAC, micropores having a diameter of 2 nm or less are called micropores. Since the micropores are generally much smaller in diameter than the hollow micropores, they can be formed in the interior of the hollow micropores within the zeolite framework to achieve a secondary microporous system.

In the micropores, the molecular diffusion rate within the micropores is greatly influenced by the interaction between the pore surface and the diffusion molecules, as compared with the hollow micropores. Thus, molecules such as the propylene of the present invention can interfere with micropores and delay diffusion rates therein. However, as described above, since micropores are formed in the hollow pores of the present invention, the micropore diffusion period may be shorter by replacing a part of the micropores with the conventional microporous zeolite. Thus, the propylene formed in the micropores can escape from the micropores sooner and spread quickly out through the hollow micropores.

In the present invention, the average diameter of the pores including the hollow pores and the fine pores formed in the crystal of the zeolite may be 3 nm or more, preferably 3 nm to 30 nm, but is not particularly limited. If the average diameter of the total pores is less than 3 nm, the hollow characteristics may not be exhibited. The average diameter of the total pores, including the hollow pores and the fine pores, can also be calculated from the nitrogen adsorption-desorption isotherm.

The zeolite having the hollow pores of the present invention can generally have a larger specific surface area than the zeolite composed of only fine pores. Therefore, the total BET specific surface area of the zeolite may be more than 350 m ² / g, and the larger the BET specific surface area is, the more preferable.

Meanwhile, the zeolite according to the present invention is not particularly limited, but is preferably H-ZSM-5. The ZSM-5 catalyst is widely used as a catalyst for producing propylene as described above. More specifically, ZSM-5 is a type of zeolite which is a crystalline aluminosilicate compound and is classified as MFI type. ZSM-5 is a crystalline material in which the central atoms, silicon and aluminum atoms, are coordinated in the form of four oxygen atoms and tetrahedra (TO ₄ ), which are regularly arranged with each other sharing vertex oxygen. In the ZSM-5, pores having a uniform size and shape are regularly formed by regularly arranging secondary building unit units of a certain shape.

ZSM-5 has a cation exchange property due to the charge difference of the skeleton because its skeletal center atom is composed of silicon and aluminum. The actual charge of an oxygen atom on one silicon atom is -1, because it shares an oxygen atom of -2 with a neighboring TO ₄ unit. Therefore, in a unit where the central atom is silicon, a negative charge of -4 oxygen atoms can be neutralized with a +4 positive charge of the silicon atom. However, the charge of the aluminum atom is +3, so additional cation is needed for the TO ₄ unit located at the center of the aluminum atom to be electrically neutral. Thus, in order for aluminum-containing zeolites to retain their electrical neutrality, ion exchange with positively charged ions is required.

With such a principle, a zeolite such as ZSM-5 is not electrically neutral and can have a acid point. Depending on the strength and density of the acid sites of the solid acid catalyst, the activity of the catalyst and the specific product selectivity may vary. From this point of view, the proper acid concentration of the zeolite catalyst is important in the production of propylene from oxygenates. In the zeolite according to the present invention, the strong acid point density is preferably 0.04 to 0.3 mmol / g when the propylene selectivity is taken into consideration. On the other hand, such a strong acid spot density depends on the aluminum content in the skeleton in the case of the H ⁺ -form type zeolite, and can generally be represented by the Si / Al atomic ratio (molar ratio) in the skeleton.

The preferred Si / Al molar ratio of the zeolite according to the present invention is 80 to 1000, more preferably 150 to 800. When the Si / Al molar ratio is less than 80, the number of strong acid sites in the zeolite increases, and the hydrogen transfer reaction in the hydrocarbons may become dominant in the production of propylene from the oxygenates. This results in an increase in the production of saturated hydrocarbons, aromatics or cokes instead of propylene, which can lower propylene selectivity and shorten catalyst life. On the other hand, if the Si / Al atomic ratio in the zeolite skeleton is larger than 1000, the number of zeolite strong acid sites is excessively reduced, that is, the number of catalytic active sites is reduced to lower the catalytic activity and the catalyst can be easily deactivated. This is because if deactivation occurs in a catalyst having a low active point density, the deactivation of the entire catalyst eventually occurs.

In general, zeolites can be deactivated in two ways in solid acid catalysis. First, the reactant or product reacts at the acid point to form a coke, which is inactivated. This makes it possible to regenerate the catalyst by burning the coke. The second case is that the aluminum that acts as the acid in the zeolite escapes from the zeolite skeleton, leading to deactivation of the acid point. The second case generally occurs irreversibly and occurs particularly well under moist conditions at high temperatures. Since this is an irreversible process, it is difficult to regenerate the catalyst, so it is necessary to prevent dealumination in the zeolite.

In the present invention, a zeolite catalyst is treated with a phosphorus (P) -containing compound to prevent irreversible dealumination as described above. As a result, the zeolite according to the present invention is modified into phosphorus (P) having an acid point, so that the hydrothermal stability of the aluminum in the framework is increased and the strong acid point is weakened and the defect site generated in the formation of the hollow in the zeolite is reduced (P). ≪ / RTI > Therefore, it has been confirmed that the catalyst of the present invention increases the selectivity of propylene and the catalyst life remarkably (Experimental Example 2).

More specifically, in the present invention, when the zeolite skeleton is modified into phosphorus by treating phosphorus (P), various models therefor can be proposed. Typically, when treated with phosphoric acid (H ₃ PO ₄ ), there is a model in which the acid point of the zeolite and the phosphorus are directly bonded by the interaction as shown in the following Chemical Formula 2 (a and b in Chemical Formula 2). Or by interaction of ions between the phosphorus and the zeolite framework (c and d in formula (2)). In the present invention, such a model is an exemplary one and is not particularly limited.

(2)

The P-OH group associated with the phosphorus acid sites is very weak in acidity, so if the phosphorus is treated excessively, the zeolite can lose its acidity significantly. In this case, even if aluminum is present in the zeolite framework, the catalyst may not have sufficient acidity to perform a reaction requiring a strong acid point, and the catalyst characteristics may be significantly deteriorated. Therefore, in the present invention, the zeolite needs to be properly controlled in the amount of phosphorus (P) to be treated, and as a result, the zeolite contains 0.1 to 10% phosphorus (P) in terms of element weight basis But is not particularly limited thereto.

In the present invention, since zeolite is generally obtained in a powder state, it is preferable to form it in order to use it as a catalyst. At this time, it is possible to maintain a physical strength higher than the titration by using an inorganic binder or a filler. The binder (or filler) may be mixed with the zeolite to form the zeolite catalyst of the present invention. At this time, the amount of the binder may be 20 to 80% by weight based on the total amount of the zeolite catalyst. If the content of zeolite in the catalyst is less than 20% by weight, the content of the zeolite is too small to sufficiently exhibit the effect as a catalyst. If it exceeds 80% by weight, the content of the inorganic binder is relatively small, It is difficult to sufficiently show the effect of the increase. The catalyst can be produced in various shapes, and examples of the method include extruding, pelletizing, rotating spherical molding, spray drying, and the like, and are not particularly limited. The binder used in the molding is preferably selected from the group consisting of clay, alumina (Al ₂ O ₃ ), silica (SiO ₂ ), silica-alumina (SiO ₂ -Al ₂ O ₃ ), metal oxides, And the filler may be selected from the group consisting of alumina (Al ₂ O ₃ ), silica (SiO ₂ ), silica-alumina (SiO ₂ -Al ₂ O ₃ ), metal oxides, clay, And is not particularly limited. The clay may include, but is not limited to, montmorillonite, saponite, kaoline, clinoptilolite, bentonite, and the like.

The zeolite catalyst according to the present invention is used as a catalyst for producing propylene from oxygenates. Particularly, since the catalyst includes zeolite having hollow pores and modified inside of the surface and pores, high propylene selectivity and excellent hydrothermal stability can be secured in the propylene production reaction.

In the present invention, the term " oxygen-containing compound " refers to a C ₁ + hydrocarbon derivative containing an oxygen atom, specifically a compound such as an alcohol, an ether and a mixture thereof. Non-limiting examples of the oxygenates include methanol, dimethyl ether, or mixtures thereof. The oxygen-containing compound is a reaction product of the reaction for producing propylene, but water (H ₂ O) and / or oxygen (O ₂ ), in addition to oxygen atoms, can be used as a reactant. That is, in general, crude methanol produced from syngas contains a certain amount of water (~ 18 wt%) and thus can be used as a reactant for propylene production without further purification.

The reaction for producing propylene from an oxygenate, in which a zeolite catalyst according to the present invention can be used, will be described later in more detail.

A second aspect of the present invention relates to a process for preparing a zeolite catalyst for the production of propylene from an oxygenate of the first aspect,

A first step of heating a slurry containing zeolite having a Si / Al molar ratio in the skeleton of 80 or more to 40 to 100 캜; A second step of adding a basic solution containing a water-soluble aluminum precursor or a quaternary ammonium ion to the slurry of the first step to form hollow pores in the zeolite; A third step of ion-exchanging the zeolite formed with the hollow pores in the second step with H ⁺ or NH ₄ ⁺ ; A fourth step of drying and firing the zeolite ion-exchanged in the third step; A fifth step of treating the dried and calcined zeolite with phosphorus (P) precursor in the fourth step; And a sixth step of firing the zeolite treated with phosphorus (P) precursor in the fifth step.

The method for producing a zeolite catalyst according to the second embodiment of the present invention is more suitable for a zeolite having a Si / Al molar ratio of 80 or more. This is a method for preparing a zeolite catalyst according to the third embodiment There is no step of dealumination or the like for increasing Si / Al since the Si / Al molar ratio in the zeolite already has a strong acid point density sufficient for the propylene production catalyst.

The first step is a step of heating a slurry containing zeolite having a Si / Al molar ratio in the skeleton of 80 or more to 40 to 100 DEG C, and the zeolite slurry is previously heated for desilication reaction of the subsequent second step .

The zeolite having a Si / Al molar ratio in the skeleton of the first step of 80 or more may have an MFI, BTA or MOR structure, preferably H-ZSM-5 zeolite. The Si / Al molar ratio is not particularly limited as long as it is 80 or more, but is preferably 80 to 1000, more preferably 150 to 800.

The slurry containing the zeolite in the first step may be a slurry in which zeolite, a surfactant and water are mixed. The water may preferably be deionized water.

The heating in the first step is preferably performed so that the zeolite-containing slurry has a temperature of 40 to 100 캜. If the temperature is lower than 40 ° C, the reaction with the base may not be sufficiently carried out to cause a problem of using too much base. If the temperature is higher than 100 ° C, the pressure vessel must be used and the silica- The yield of zeolite may be lowered.

The second step is to add a basic solution containing a water-soluble aluminum precursor or a quaternary ammonium ion to the slurry of the first step to form hollow pores in the zeolite, and a hollow pore is formed in the zeolite by a desilica reaction .

The second step is to form a hollow pore by partial dissolution (desilica reaction) of the zeolite by adding a basic solution to the heated zeolite slurry of the first step, wherein the basic solution contains a water soluble aluminum precursor or 4 It is preferable that a secondary ammonium ion is contained. In particular, in the case of a zeolite having a high silica content (Si / Al molar ratio of 80 or more), aluminum ions are relatively small in the zeolite skeleton, which makes it difficult to precisely introduce hollow pores into a basic solution. At this time, more sophisticated hollow pores can be introduced by protecting the zeolite surface with aluminum ions or quaternary ammonium ions.

The water soluble aluminum precursor includes, but is not limited to, an aluminum cation salt such as aluminum chloride (AlCl ₃ ) or aluminum nitrate (Al (NO ₃ ) ₃ ) or an aluminum anion salt such as sodium aluminate (NaAlO ₂ ) ) Or a mixture of the cationic salt and the anionic salt, but is not particularly limited thereto.

The quaternary ammonium ion may be a compound represented by the following general formula (1).

[Chemical Formula 1]

In Formula 1, R 1 to R 4 may each independently be C ₁ to C ₁₀ alkyl or aryl.

More specifically, non-limiting examples of the quaternary ammonium ion include tetraethylammonium ion, tetrapropylammonium ion, tetrabutylammonium ion, and the corresponding anion (OH ^- ), halide (halide, Cl ^- , Br ^- , I ^- ), and the like are not particularly limited.

The basic solution may be a base used in a desilication reaction and may be, without limitation, a strong base such as sodium hydroxide (NaOH), potassium hydroxide (KOH), or a combination thereof, or may be sodium carbonate (Na ₂ CO ₃ ) A weak base such as potassium carbonate (K ₂ CO ₃ ) or a combination thereof.

The amount of the strong base in the basic solution used in the second step may be 0.1 to 1 mole based on the mole of silica of the zeolite. If the amount of the strong base is less than 0.1 mol / Si mol, the formation of hollow pores may not be sufficient in the zeolite, and if it is larger than 1 mol / Si mol, excess silica removal reaction may occur in the zeolite and the yield of the hollow pore zeolite may decrease .

In the second step, the basic solution may be slowly added thereto while the slurry of the first step is being stirred to form hollow pores in the zeolite by desilication. More specifically, in the second step, the basic solution is slowly added with stirring while maintaining the temperature of the slurry in the first step, and the desilylation reaction can be sufficiently performed while maintaining the slurry for 10 minutes to 24 hours.

The third step of the method comprising an ion exchange zeolite is hollow pores formed in the second step to the H + or NH4 +, the removed non-skeleton (non-framework) aluminum ions attached to the surface of zeolite and ion exchange H ⁺ -form Treating the acid to prepare the zeolite or treating the salt with NH ₄ ⁺ .

The H + phosphorus acid is not particularly limited as long as it is an acid capable of generating H ⁺ ions in an aqueous solution, but examples thereof include hydrochloric acid, nitric acid, oxalic acid, and the like. The NH ₄ ⁺ phosphorus salt is not particularly limited as long as it is a compound capable of generating NH ₄ ⁺ ions in an aqueous solution, but examples thereof include ammonium nitrate (NH ₄ NO ₃ ), ammonium chloride (NH ₄ Cl) And so on.

In the present invention, the step of removing the liberated silica ions by sufficiently washing the slurry of the second step formed with hollow pores with deionized water may be further performed before the third step.

The fourth step is a step of drying and firing the ion-exchanged zeolite in the third step, and drying and firing the ion-exchanged H ⁺ -form zeolite to prepare a zeolite having hollow pores.

The firing may be performed at a temperature of 200 ° C to 700 ° C, but is not particularly limited.

Step 5 is a step of treating zeolite dried and calcined in the fourth step with phosphorus (P) precursor, and modifying the surface and pores of the zeolite having the hollow pores to phosphorus (P).

The phosphorus (P) precursor is not particularly limited as long as it contains phosphorus (P) in its chemical structure and is capable of reacting with the acid point of the zeolite. Without limitation, the phosphorus (P) precursor may be a phosphate compound selected from the group consisting of phosphoric acid (H ₃ PO ₄ ), NH ₄ H ₂ PO ₄ , (NH ₄ ) ₂ HPO ₄ and mixtures thereof, There may be organic phosphite of a size that can be made. In one embodiment of the present invention, trimethyl phophite may be used as the phosphorus (P) precursor.

As a method of treating the phosphorus (P) precursor, a solution containing phosphorus (P) precursor may be impregnated with zeolite or may be used by chemical vapor deposition (CVD). When the chemical vapor deposition method is used, the phosphorus (P) precursor can be heated to become a gas, and then the phosphorus (P) precursor in a gaseous state can diffuse into the pores of the zeolite and react with the acid point.

The sixth step is a step of calcining the zeolite treated with the phosphorus (P) precursor in the fifth step, finally obtaining zeolite catalyst for producing propylene from the oxygenate according to the present invention.

The firing may be performed at a temperature of 200 ° C to 700 ° C, but is not particularly limited.

A third aspect of the present invention relates to a process for preparing a zeolite catalyst for the production of propylene from an oxygenate of the first aspect,

A first step of heating a slurry containing zeolite having a Si / Al molar ratio in the skeleton of 80 or less to 40 to 100 캜; A second step of adding a basic solution to the slurry of the first step to form hollow pores in the zeolite; A third step of removing a part of aluminum in the zeolite framework by heating the zeolite formed with the hollow pores in the second step under steam; A fourth step of treating the steam-treated zeolite in the third step with an acid to remove the non-skeletal aluminum of the zeolite; A fifth step of treating the acid-treated zeolite with phosphorus (P) precursor in the fourth step; And a sixth step of firing the zeolite treated with phosphorus (P) precursor in the fifth step.

The method for producing a zeolite catalyst according to the third aspect of the present invention is more particularly suitable for a zeolite having a Si / Al molar ratio of 80 or less, which is a process for preparing a zeolite catalyst according to the second embodiment Unlike the method, since the Si / Al molar ratio in the zeolite has not reached a suitable level in the catalyst for producing propylene, it includes steps such as dealumination to increase it.

The first step is a step of heating a slurry containing zeolite having a Si / Al molar ratio in the skeleton of 80 or less to 40 to 100 캜, and a detailed description thereof is as described in the first step of the second embodiment. However, the first stage zeolite may be a zeolite having a Si / Al molar ratio within the framework of 80 or less, preferably a Si / Al molar ratio of 10 to 80.

In the second step, a basic solution is added to the slurry of the first step to form hollow pores in the zeolite, and a hollow pore is formed by a desilylation reaction through a basic solution. A detailed description of the second step is as described in the second step of the second embodiment. However, in the second step according to the third embodiment, the basic solution need not contain a water-soluble aluminum precursor or a quaternary ammonium ion, unlike the second embodiment, which can be appropriately selected by those skilled in the art. This is because the production method according to the third embodiment is advantageous in that the Si / Al molar ratio of the zeolite is in a range (20 to 80) which is easy to form hollow by the basic solution and the addition of a separate aluminum precursor or quaternary ammonium ion It may not necessarily be necessary to add additional protective material since formation can occur relatively easily.

The third step is a step of heating the zeolite formed with the hollow pores in the second step under steam to remove a part of aluminum in the zeolite skeleton. The step of dealumination is carried out by dealumination through steaming, By partially removing aluminum, the Si / Al molar ratio in the framework is increased to the range of 100 to 1000.

The production method according to the third aspect is that the Si / Al molar ratio of the zeolite is relatively low, so that the strong acid point may exceed the level required in the propylene production reaction. Therefore, it is necessary to increase the Si / Al molar ratio in the zeolite skeleton to an appropriate level through dealumination. The desalination reaction in the third step may be carried out by steam partial pressure of 50% to 100% and steam at 500 to 850 ° C. If the steam partial pressure is lower than 50%, the dealumination reaction may proceed slowly, so it may be preferable to perform at 50% or higher. If the reaction temperature is lower than 500 ° C, the dealumination reaction may not occur well. If the reaction temperature is higher than 850 ° C, the dealumination reaction becomes excessively excessive, and the amount of Al acting as an acid point in the skeleton of the zeolite becomes too small There is a problem that the catalyst activity is lowered.

In the fourth step, the non-skeletal aluminum of the zeolite is removed by treating the steam-treated zeolite with the acid in the third step, and the non-skeletal aluminum produced by the dealumination of the third step And is removed by an acid treatment.

The acid is not particularly limited as long as it is an acid capable of generating H ⁺ ions in an aqueous solution, but examples thereof include hydrochloric acid, nitric acid, oxalic acid, and the like.

The step of drying and firing the acid-treated zeolite in the fourth step after the fourth step may further be carried out. The firing may be performed at a temperature of 200 ° C to 700 ° C, but is not particularly limited.

The fifth step is a step of treating the acid-treated zeolite with the phosphorus (P) precursor in the fourth step, and a detailed description thereof is as described in the fifth step of the second embodiment.

The sixth step is a step of firing the zeolite treated with the phosphorus (P) precursor in the fifth step, and a detailed description thereof is as described in the sixth step of the second embodiment.

A fourth aspect of the present invention relates to a process for producing propylene from an oxygenate under the zeolite catalyst prepared by the zeolite catalyst of the first aspect, the process of the second or third aspect.

The oxygenate is preferably methanol, dimethyl ether or a mixture thereof, and may further contain water (H ₂ O) and / or oxygen (O ₂ ). A more detailed description thereof is as described in the first embodiment.

The reaction for producing propylene from the oxygen-containing compound can be carried out under the conditions of the propylene-producing reaction which is conventional in the art, and is not particularly limited thereto. More specifically, the propylene production reaction can be carried out at a reaction temperature of 300 to 700 ° C, preferably 400 to 700 ° C, and a reaction pressure of 0.1 to 5 atm, preferably 0.1 to 3 atm. If the reaction temperature is lower than 300 ° C, the reaction may not be smooth and the yield of propylene may be lowered. If the reaction temperature is higher than 700 ° C, generation of coke in the zeolite-based shaped catalyst may be accelerated and the catalyst may be inactivated rapidly . If the reaction pressure is less than 0.1 atm, the productivity of the reaction decreases. If the pressure exceeds 5 atm, the production of C ₅ + hydrocarbons may increase and the production of coke may increase in the catalyst.

The reactant oxygenate can be fed at a reaction flow rate of 1 to 30 g / g _cat h. If WHSV is less than 1 g / g _cat h, there is a problem that the production of coke is increased and the productivity is inferior. When WHSV = 30 g / g _cat h, the propylene selectivity is low May occur.

The zeolite catalyst having hollow pores of the present invention can have high selectivity for propylene, long catalyst life, and excellent hydrothermal stability in the production of propylene from a carbide, and therefore, propylene can be produced more economically.

1 is a TEM photograph of a zeolite catalyst prepared according to Example 1 and Comparative Example 2 of the present invention.
2 is a graph showing nitrogen adsorption / desorption isotherms of zeolite catalysts prepared according to Example 1 and Comparative Example 2 of the present invention.
FIG. 3 is a graph showing the selectivity of propylene with respect to the reaction time in the production of propylene of the zeolite catalyst prepared according to Examples and Comparative Examples of the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples. These embodiments are only for illustrating the present invention, and the scope of the present invention is not construed as being limited by these embodiments.

Example  1: P / HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 280) and 2.1 g of a surfactant Triton X-100 were mixed with 80.0 g of deionized water to prepare a slurry, which was then heated to 70 ° C. with stirring. To the heated solution was added an aqueous solution containing 0.85 g of tetrapropylammonium bromide (TPABr) dissolved in 80 g of a 1M aqueous solution of sodium hydroxide (NaOH), and the slurry was stirred for 1 hour. The stirred slurry was washed with water by filtration and then dried at 100 ° C. 200 cc of 1 M ammonium chloride (NH ₄ Cl) was further added thereto, and the mixture was heated to 70 ° C for ion exchange. This was washed with water and dried at 100 ° C, and NH ₄ -ZSM-5 was prepared by repeating the ion exchange process with ammonia chloride two more times. This was calcined at 550 ° C. to finally produce a HZSM-5 catalyst having hollow pores.

5 g of HZSM-5 having the above-prepared hollow pores was placed in an autoclave of 200 ml capacity and vials containing 0.036 g of trimethylphosphite were placed and kept at 200 ° C for 20 hours. At this time, the trimethylphosphite was vaporized and diffused into the zeolite pores, and then reacted with an acid at the aluminum in the pores. Then, it was calcined at 550 ° C for 5 hours to prepare a P / HZSM-5 catalyst.

Example  2: P / HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 280) and 1.3 g of surfactant Triton X-100 were mixed with 60.0 g of deionized water to prepare a slurry, which was then heated to 60 ° C. with stirring. To the heated solution was added an aqueous solution in which 0.85 g of tetrapropylammonium bromide was dissolved in 100 g of a 1 M sodium hydroxide (NaOH) aqueous solution, and then the slurry was stirred for 1 hour. The agitated slurry was ion-exchanged with ammonium chloride (NH4Cl) in the same manner as in Example 1, and calcined to finally produce HZSM-5 catalyst having hollow pores.

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.036 g of trimethyl phosphite was applied to 5 g of HZSM-5 having the above-prepared hollow pores.

Example  3: P / HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 280) and 2.1 g of a surfactant Triton X-100 were mixed with 50.0 g of deionized water to prepare a slurry, which was then heated to 80 ° C. with stirring. To the heated solution was added an aqueous solution containing 0.85 g of tetrapropylammonium bromide dissolved in 120 g of a 1 M sodium hydroxide (NaOH) aqueous solution, and the slurry was stirred for 1 hour. The agitated slurry was ion-exchanged with ammonium chloride (NH ₄ Cl) in the same manner as in Example 1, and calcined to finally produce a HZSM-5 catalyst having hollow pores.

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.075 g of trimethyl phosphite was applied to 5 g of HZSM-5 having the above prepared hollow pores.

Example  4: P / HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 280) and 2.1 g of a surfactant Triton X-100 were mixed with 60.0 g of deionized water to prepare a slurry, which was then heated to 70 ° C. with stirring. To the heated solution was added an aqueous solution in which 0.88 g of sodium aluminate (NaAlO ₂ , Al ₂ O ₃ -36 wt%, Na ₂ O-32 wt%) was dissolved in 100 g of an aqueous solution of 1 M sodium hydroxide (NaOH) Lt; / RTI > The agitated slurry was ion-exchanged with ammonium chloride (NH ₄ Cl) in the same manner as in Example 1, and calcined to finally produce a HZSM-5 catalyst having hollow pores.

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.096 g of trimethyl phosphite was applied to 5 g of HZSM-5 having the above-prepared hollow pores.

Example  5: P / HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 280) and 2.1 g of a surfactant Triton X-100 were mixed with 90.0 g of deionized water to prepare a slurry, which was then heated to 70 ° C. with stirring. To the heated solution was added an aqueous solution in which 0.63 g of sodium aluminate (NaAlO ₂ , Al ₂ O ₃ -36 wt%, Na ₂ O-32 wt%) was dissolved in 60 g of an aqueous solution of 1 M sodium hydroxide (NaOH) Lt; / RTI > The agitated slurry was ion-exchanged with ammonium chloride (NH ₄ Cl) in the same manner as in Example 1, and calcined to finally produce a HZSM-5 catalyst having hollow pores.

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.148 g of trimethyl phosphite was applied to 5 g of HZSM-5 having the above prepared hollow pores.

Example  6: P / HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 80) and 2.1 g of a surfactant Triton X-100 were mixed with 150 g of a 0.6M sodium hydroxide (NaOH) aqueous solution to prepare a slurry, which was heated to 70 ° C with stirring . After the heated slurry was stirred for 1 hour, the slurry was ion-exchanged with ammonium chloride (NH ₄ Cl) in the same manner as in Example 1 and calcined to prepare HZSM-5 catalyst having hollow pores. The HZSM-5 zeolite was mounted in a tubular furnace and deionized water was injected at a rate of 0.5 cc / min using a liquid pump and steaming was performed. In the steaming, the heating furnace was heated to 650 ° C at a rate of 5 ° C / min, and then partially dealluminated in the zeolite skeleton while maintaining the temperature for 5 hours. To remove the non-skeletal aluminum of the treated zeolite, 100 ml of 1M oxalic acid was added and the mixture was heated to 70 ° C and then filtered and washed with water. Further, the catalyst was dried at 100 ° C and calcined at 550 ° C to prepare a HZSM-5 catalyst having an increased Si / Al atomic ratio and hollow pores.

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.163 g of trimethyl phosphite was applied to 5 g of HZSM-5 having the above prepared hollow pores.

Example  7: P / HZSM -5 catalyst

HZSM-5 having hollow pores was prepared by using HZSM-5 (SiO ₂ / Al ₂ O ₃ = 80) in the same manner as in Example 6, and the dealumination reaction by steam ming was performed at 700 ° C.

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.120 g of trimethyl phosphite was applied to 5 g of HZSM-5 having the above prepared hollow pores.

Example  8: P / HZSM -5 catalyst

HZSM-5 having hollow pores was prepared using HZSM-5 (SiO ₂ / Al ₂ O ₃ = 80) in the same manner as in Example 6, except that the dealumination reaction by steam ming was performed at 750 ° C.

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.098 g of trimethyl phosphite was applied to 5 g of HZSM-5 having the above prepared hollow pores.

Example  9: P / HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 80) and 2.1 g of a surfactant Triton X-100 were mixed with 160 g of a 0.6M sodium hydroxide (NaOH) aqueous solution to prepare a slurry, which was then heated to 80 ° C with stirring . After the heated slurry was stirred for 1 hour, the slurry was ion-exchanged with ammonium chloride (NH ₄ Cl) in the same manner as in Example 1 and calcined to prepare HZSM-5 catalyst having hollow pores. The HZSM-5 zeolite was mounted on a tubular heating furnace, and deionized water was injected at a rate of 0.5 cc / min using a liquid pump and steamed. In the steaming, the heating furnace was heated to 700 ° C at 5 ° C / min, and then partially dealluminated in the zeolite skeleton while maintaining this temperature for 5 hours. To remove the non-skeletal aluminum of the treated zeolite, 3 ml of hydrochloric acid was added to 100 cc, which was then filtered and washed with water. Further, the catalyst was dried at 100 ° C and calcined at 550 ° C to prepare a HZSM-5 catalyst having an increased Si / Al atomic ratio and hollow pores.

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.117 g of trimethyl phosphite was applied to 5 g of HZSM-5 having the above prepared hollow pores.

Comparative Example  1: only with fine pores HZSM -5 catalyst

HZSM-5 (SiO ₂ / Al ₂ O ₃ = 280) consisting of micropore was obtained from (-) and prepared as a catalyst.

Comparative Example  2: only with fine pores HZSM -5 catalyst

HZSM-5 (SiO ₂ / Al ₂ O ₃ = 80) consisting of micropore was obtained from (-) and prepared as a catalyst.

Comparative Example  3: Having hollow pores HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 80) and 2.1 g of a surfactant Triton X-100 were mixed with 150 g of a 0.6M sodium hydroxide (NaOH) aqueous solution to prepare a slurry, which was heated to 70 ° C with stirring . After the heated slurry was stirred for 1 hour, the slurry was ion-exchanged with ammonium chloride (NH ₄ Cl) in the same manner as in Example 1 and calcined to prepare HZSM-5 catalyst having hollow pores.

Comparative Example  4: P / HZSM -5 catalyst

5 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 280) having fine pores only prepared in Comparative Example 1 was placed in an autoclave of 200 ml capacity and vials containing 0.073 g of trimethylphosphite ) Was placed and kept at 200 ° C for 20 hours. At this time, the trimethylphosphite was vaporized and diffused into the zeolite pores, and then reacted with an acid at the aluminum in the pores. Thereafter, it was calcined at 550 ° C for 5 hours to prepare a P / HZSM-5 catalyst having only fine pores.

Comparative Example  5: Having hollow pores HZSM -5 catalyst

20 g of HZSM-5 (SiO ₂ / Al ₂ O ₃ = 280) and 2.1 g of a surfactant Triton X-100 were mixed with 80.0 g of deionized water to prepare a slurry, which was then heated to 70 ° C. with stirring. To the heated solution was added a solution in which 0.85 g of tetrapropylammonium bromide was dissolved in 80 g of a 1 M sodium hydroxide (NaOH) aqueous solution, and the slurry was stirred for 1 hour. The stirred slurry was washed with water by filtration and then dried at 100 ° C. 200 cc of 1 M ammonium chloride (NH ₄ Cl) was further added thereto, and the mixture was heated to 70 ° C for ion exchange. This was washed with water and dried at 100 ° C, and NH ₄ -ZSM-5 was prepared by repeating the ion exchange process with ammonia chloride two more times. This was calcined at 550 ° C. to finally produce a HZSM-5 catalyst having hollow pores.

Comparative Example  6: Poorly treated P, P / HZSM -5 catalyst

A P / HZSM-5 catalyst was prepared in the same manner as in Example 1, except that 0.249 g of trimethyl phosphite was over-applied to 5 g of HZSM-5 having a hollow pore prepared in Comparative Example 5.

Experimental Example  1: Analysis of catalyst characteristics

The characteristics of the zeolite catalyst prepared according to Examples 1 to 9 and the zeolite catalysts prepared according to Comparative Examples 1 to 6 were analyzed as follows.

TEM photographs of each of the prepared zeolite catalysts were taken and the results are shown in FIG. As shown in FIG. 1, the zeolite catalyst according to the present invention (Example 1) has a hollow pore well formed as compared with Comparative Example 2, which is a conventional zeolite catalyst.

For each zeolite catalyst prepared, the elements of the zeolite were analyzed using XRF. In addition, nitrogen adsorption isotherms at -196 ℃ - by performing a desorption experiment, the nitrogen isothermal adsorption-desorption was analyzed for pore properties by the curve (N ₂ adsorption desorption isotherm &), the nitrogen isothermal adsorption-desorption curve was also indicated in the 2 . Further, the concentration of strong acid densities was determined by quantifying ammonia desorbed near 300 to 550 ° C. using NH 3-TPD (temperature programmed desorption). The results are shown in Table 1 below.

catalyst Pore characteristics * Elemental analysis ** Strong acid spot density,
mmol / g *** BET
SA
(m ² / g) Micropore
volume
(cc / g) Mesopore
volume
(cc / g) Al,
mol% Si,
mol% P,
mol% Si / Al
mol ratio Example 1 512 0.107 0.445 0.74 98.90 0.36 133.6 0.15 Example 2 523 0.102 0.436 0.73 98.75 0.52 135.3 0.13 Example 3 518 0.106 0.457 0.75 98.48 0.77 131.3 0.11 Example 4 519 0.104 0.490 0.74 99.26 0.97 134.1 0.095 Example 5 535 0.100 0.615 0.75 99.25 1.52 132.3 0.082 Example 6 489 0.111 0.395 1.02 98.77 1.67 97.1 0.074 Example 7 471 0.107 0.387 0.88 99.00 1.23 112.8 0.086 Example 8 441 0.107 0.402 0.74 99.20 1.00 134.4 0.098 Example 9 482 0.108 0.393 0.86 98.97 1.20 115.1 0.088 Comparative Example 1 385 0.098 0.025 0.66 99.14 0.00 150.2 0.16 Comparative Example 2 452 0.105 0.072 2.10 97.70 0.00 46.5 0.47 Comparative Example 3 521 0.126 0.337 2.31 97.36 0.00 42.2 0.52 Comparative Example 4 379 0.096 0.024 0.65 98.34 1.00 150.2 0.102 Comparative Example 5 512 0.107 0.445 0.74 99.26 0.00 133.6 0.17 Comparative Example 6 506 0.093 0.425 0.72 95.88 3.40 133.6 0.025 * Wanted by nitrogen adsorption-desorption isothermal experiment at -196 ℃
** Elemental analysis by X-ray fluorescence (XRF)
*** Wanted by Ammonia Temperature Deposition Method

Experimental Example  2: Under the catalyst From oxygenates  Production of propylene

Experiments for preparing propylene from oxygenates in the presence of zeolite catalysts prepared according to Examples 1 to 9 and zeolite catalysts prepared according to Comparative Examples 1 to 6 were carried out as follows.

First, the catalysts prepared in Examples 1 to 9 and Comparative Examples 1 to 6 were pelletized and pulverized and separated into 0.8 to 1.1 mm sizes. Alumina balls of 1 mm in size with the catalyst were mounted on stainless steel tubes having an outer diameter of 3/8 inch using a catalyst diluent.

In a fixed bed reactor equipped with a catalyst containing a diluent, a catalyst activation process was performed at atmospheric pressure and at 480 ° C for 1 hour under a flow of 130 cc / min nitrogen. The reaction was carried out at a flow rate of WHSV = 9 h ^-1 using a liquid pump (LC pump) under the same temperature and pressure under a flow of nitrogen in a methanol (crude methanol, 20 wt% H ₂ O). The reaction products were analyzed by gas chromatography (GC), separated by GasPro column, and detected by FID, respectively. The results of the propylene-containing products prepared in the above reaction are shown in Table 2 and FIG.

catalyst Conversion Rate
(%) Product Distribution (%) Catalyst lifetime (h) * C ₁ -C ₄ C ₂ = C ₈ = C ₄ = C ₅ + B.T.X. Example 1 100 4.3 5.76 40.08 20.87 28.99 3.12 145 Example 2 100 3.9 5.65 40.23 21.56 28.66 2.95 161 Example 3 100 3.04 6.23 40.47 22.18 28.09 2.78 185 Example 4 100 2.52 5.21 41.3 21.2 29.77 2.45 193 Example 5 100 1.86 4.77 42.07 21.13 30.17 1.81 230 Example 6 100 1.72 4.23 42.3 21.53 30.22 1.95 201 Example 7 100 2.78 5.64 41.45 21.6 28.53 2.34 195 Example 7 100 2.67 5.74 42.54 22.14 26.91 2.75 176 Example 9 100 2.82 5.48 41.75 21.84 28.11 2.27 183 Comparative Example 1 100 4.93 8.43 38.81 20.38 27.44 4.88 30 Comparative Example 2 100 12.78 11.54 27.42 12.14 35.83 10.79 3 Comparative Example 3 100 13.21 12.12 26.54 13.57 34.56 11.38 11 Comparative Example 4 100 1.75 5.72 42.38 22.2 27.95 2.2 98 Comparative Example 5 100 5.47 6.98 38.03 20.42 29.09 4.2 40 Comparative Example 6 100 1.12 3.78 37.56 23.62 33.92 1.17 64 * The catalyst life is the reaction time until the selectivity of propylene is maintained at 30%.

As shown in Table 2 and FIG. 3, the catalysts of Examples 1 to 9 according to the present invention, that is, catalysts having hollow pores modified with phosphorus (P) and having a strong acid point density, %, Respectively. In addition, it can be confirmed that the catalyst life is more than 140 hours. Furthermore, since aromatics products such as paraffin and BTX (benzene, toluene, xylene) are low, there is a high possibility that propylene yield can be further increased when the product recycle process is applied. On the other hand, in the catalysts of Comparative Examples 1 to 6, the propylene selectivity and the catalyst lifetime are relatively low as compared with the catalysts of Examples 1 to 9, and the selectivity of the paraffin or aromatics product is high, It can be confirmed that the yield of propylene can be lowered.

Specifically, even though the density of the strong acid sites is controlled as in Comparative Example 1, the catalyst life of the HZSM-5 catalyst made of micropore is as short as 30 hours. The catalyst life is still lower than that of the hollow pore catalyst according to Examples 1 to 9 (98 hours) even when the propylene selectivity and catalyst life are improved by further modifying it to phosphorus (P) as in Comparative Example 4.

When the density of the strong acid sites is too high as in Comparative Examples 2 and 3, the propene selectivity and catalyst life are remarkably decreased.

As shown in Comparative Example 5, even if the density of the strong acid sites was appropriately controlled with hollow pores, it was confirmed that the propylene selectivity was somewhat lowered when paraffin (P) was not modified, paraffin and aromatics byproducts were increased, .

On the other hand, as shown in Comparative Example 6, when the phosphorus (P) is excessively treated even if it has hollow pores, the catalyst activity is lowered due to the low specific acid density and propylene selectivity is lowered and the catalyst life is lowered.

Claims (23)

A catalyst comprising a zeolite having a mesopore in the crystal and a micropore formed in the hollow pore,
Wherein the average diameter of the total pores including the hollow pores and the fine pores is 3 nm or more, the pore volume is 0.1 cc / g or more,
The total BET specific surface area of the zeolite is 350 m ² / g or more,
The density of the strong acid point of the zeolite is 0.04 to 0.3 mmol / g,
Characterized in that the zeolite has its surface and pore interior modified with phosphorus (P). The zeolite catalyst for the production of propylene from oxygenates.
The zeolite catalyst for the production of propylene from an oxygenate as claimed in claim 1, wherein the zeolite further has a hollow pore introduced into the zeolite having an MFI, BTA or MOR structure.
The zeolite catalyst for the production of propylene from an oxygenate as claimed in claim 1, wherein the zeolite further has a hollow pore introduced into H-ZSM-5.
The zeolite catalyst according to claim 1, wherein the zeolite has an Si / Al molar ratio of 80 to 1000.
The zeolite catalyst for the production of propylene from an oxygenate according to claim 1, wherein the zeolite contains 0.1 to 10% phosphorus (P) based on the weight of the zeolite on an element basis.
The zeolite catalyst for the production of propylene from an oxygenate as claimed in claim 1, further comprising a binder for shaping.
2. The zeolite catalyst according to claim 1, wherein the binder is selected from the group consisting of clay, alumina, silica, silica-alumina, metal oxide, phosphate and mixtures thereof.
The zeolite catalyst for the production of propylene from an oxygenate as claimed in claim 1, wherein the oxygen-containing compound is a C ₁ + hydrocarbon derivative containing an oxygen atom.
The zeolite catalyst for the production of propylene from an oxygenate as claimed in claim 8, wherein the oxygenate is an alcohol, an ether or a mixture thereof.
A process for preparing a zeolite catalyst for the production of propylene from the oxygenates of any one of claims 1 to 9, comprising the steps of:
A first step of heating a slurry containing zeolite having a Si / Al molar ratio in the skeleton of 80 or more to 40 to 100 캜;
A second step of adding a basic solution containing a water-soluble aluminum precursor or quaternary ammonium ions to the slurry of the first stage to form hollow pores in the zeolite;
A third step of ion-exchanging the zeolite formed with the hollow pores in the second step with H ⁺ or NH4 ⁺ ;
A fourth step of drying and firing the zeolite ion-exchanged in the third step;
A fifth step of treating the dried and calcined zeolite with phosphorus (P) precursor in the fourth step; And
And a sixth step of firing the zeolite treated with phosphorus (P) precursor in the fifth step.
The method of claim 10, wherein the aluminum precursor in the second step is selected from the group consisting of aluminum chloride (AlCl ₃ ), aluminum nitrate (Al (NO ₃ ) ₃ ), sodium aluminate (NaAlO ₂ ) Wherein the zeolite catalyst is prepared from propylene oxide.
[Claim 11] The method according to claim 10, wherein the quaternary ammonium ion in the second step is a compound represented by the following Formula 1:
[Chemical Formula 1]

In Formula 1, R 1 to R 4 are each independently C ₁ to C ₁₀ alkyl or aryl.
13. The method of claim 12, wherein the quaternary ammonium ion in the second step is selected from the group consisting of tetraethylammonium ions, tetrapropylammonium ions, tetrabutylammonium ions, ≪ / RTI > wherein the zeolite catalyst is selected from the group consisting of zeolite and zeolite.
The method according to claim 10, wherein the phosphorus (P) precursor in the fifth step is a phosphate compound selected from the group consisting of phosphoric acid (H ₃ PO ₄ ), NH ₄ H ₂ PO ₄ , (NH ₄ ) ₂ HPO _4, Wherein the zeolite catalyst is an organic phosphite having a size capable of penetrating into the zeolite pores of the fifth step.
11. The method of claim 10, wherein the phosphorus (P) precursor treatment in the fifth step is performed by chemical vapor deposition.
A process for preparing a zeolite catalyst for the production of propylene from the oxygenates of any one of claims 1 to 9, comprising the steps of:
A first step of heating a slurry containing zeolite having a Si / Al molar ratio in the skeleton of 80 or less to 40 to 100 캜;
A second step of adding a basic solution to the slurry of the first step to form hollow pores in the zeolite;
A third step of removing a part of aluminum in the zeolite framework by heating the zeolite formed with the hollow pores in the second step under steam;
A fourth step of treating the steam-treated zeolite in the third step with an acid to remove the non-skeletal aluminum of the zeolite;
A fifth step of treating the acid-treated zeolite with phosphorus (P) precursor in the fourth step; And
And a sixth step of firing the zeolite treated with phosphorus (P) precursor in the fifth step.
17. The method of claim 16, wherein the third step is performed at a steam partial pressure of 50% to 100% and at a temperature of 500 to 850 캜.
17. The method of claim 16, wherein the third step is to deal with a portion of the aluminum in the zeolite framework, thereby increasing the Si / Al molar ratio in the zeolite framework from 100 to 1000. The zeolite catalyst ≪ / RTI >
The method according to claim 16, wherein the phosphorus (P) precursor in the fifth step is a phosphate compound selected from the group consisting of phosphoric acid (H ₃ PO ₄ ), NH ₄ H ₂ PO ₄ , (NH ₄ ) ₂ HPO _4, Wherein the zeolite catalyst is an organic phosphite having a size capable of penetrating into the zeolite pores of the fifth step.
17. The method of claim 16, wherein the phosphorus (P) precursor treatment in the fifth step is performed by chemical vapor deposition.
A process for producing propylene from a zeolite catalyst according to any one of claims 1 to 9 or zeolite catalyst prepared according to any one of claims 11 to 15.
22. The process according to claim 21, wherein the reaction for preparing propylene from the oxygenated product is carried out at a reaction temperature of 400 to 700 占 폚, a reaction pressure of 0.1 to 3 atm and a reaction flow rate of 1 to 30 g / g _cat h Propylene.
22. The method of claim 21, wherein the oxygenate is methanol, dimethyl ether, or a mixture thereof.

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