JPH0674134B2 - Alkaline earth metal-containing aluminophosphosilicate, method for producing the same, and method for producing lower olefin using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel alkaline earth metal-containing aluminophosphosilicate (hereinafter sometimes simply referred to as zeolite or aluminophosphosilicate), a method for producing the same, and a method for producing the same. Regarding a method for producing a lower olefin used as a catalyst, specifically, a novel zeolite that can be effectively used as a catalyst for various chemical reactions, particularly a catalyst for producing a lower olefin such as ethylene and propylene, and an efficient production method thereof And a method for efficiently producing a lower olefin using this novel zeolite.

The aluminophosphosilicate of the present invention has a higher SiO ₂ / Al ₂ O ₃ ratio than conventionally known zeolite catalysts, and has a high alkaline earth metal content, and at least one of the alkaline earth metals is Parts are not easily exchanged for other ions by ion exchange methods, and this high alkaline earth metal content is not introduced by conventional ion exchange methods.

A feature of the method for producing an aluminophosphosilicate of the present invention is that phosphorus and an alkaline earth metal salt are previously present as a part of the raw material for producing an aluminophosphosilicate during production of an aluminophosphosilicate.

Furthermore, the method for producing a lower olefin of the present invention relates to a method for producing a C ₂ -C ₄ lower olefin, which comprises contacting methanol and / or dimethyl ether with the above aluminophosphosilicate under heating in a gas phase, and CO
And less decomposition to CO ₂ and lower olefins are obtained with high selectivity, paraffin and aromatic by-products are less, carbon deposition on the catalyst is suppressed, and catalytic activity does not decrease and catalyst does not deteriorate even at high temperatures. .

In recent years, there has been concern about the supply of petroleum resources, and especially in Japan, where the rate of dependence on foreign countries exceeds 99%, the effective use of coal, natural gas, etc. has become an important issue. It is required to establish an industrial synthesis method of organic compounds such as olefins, paraffins and aromatics from methanol obtained from the above. The present invention meets this need.

[Problems to be Solved by Conventional Techniques and Inventions] Various crystalline aluminosilicates have hitherto been known, and among them, crystalline aluminosilicate zeolite is the most typical one. Crystalline aluminosilicate zeolite exists naturally in large numbers, and is also obtained by synthesis, has a certain crystal structure, and has a large number of voids and tunnels in the structure, whereby molecules up to a certain size are adsorbed, Anything more than that has the function of eliminating, and is also called a molecular sieve. The pores formed by voids and tunnels are determined by the form in which SiO ₂ and Al ₂ O ₃ covalently bond with oxygen in the crystal structure. The electronegative nature of the aluminum-containing tetrahedra is usually kept electrically neutral by alkali metal ions, especially sodium and / or potassium.

Usually, in order to produce a crystalline aluminosilicate zeolite, a method of mixing SiO ₂ , Al ₂ O ₃ , each source of alkali metal ions and water in a desired ratio, and performing hydrothermal treatment under normal pressure or pressure is a method. Has been taken. There is also a method of using an organic nitrogen compound as a base, whereby various zeolites having various adsorption capacities and catalytic functions are synthesized,
In recent years, the synthesis of this type of zeolite has been very active. In particular, ZSM type zeolite by Mobil Oil Co. is synthesized by using tetraalkylammonium compound, pyrrolidine, ethylenediamine, choline and the like, and its unique adsorption ability and catalytic action have been attracting attention. Among them, ZSM-5 is 5
Since it has a medium pore size of 6Å, it has a property of adsorbing linear hydrocarbons and slightly branched hydrocarbons, but not adsorbing highly branched hydrocarbons. This ZSM-5 is usually synthesized by hydrothermal treatment of a mixture of SiO ₂ , Al ₂ O ₃ , each source of alkali metal, water and a tetra-n-propylammonium compound (JP-A-52-43800). Issue).

In recent years, researches for obtaining hydrocarbons by reacting methanol and / or dimethyl ether have been very active. The catalyst used in this reaction is generally called a solid acid, and many patents have been applied for various zeolites, heteropolyacids and the like. In particular, ZSM-5 by Mobile Oil Co., Ltd. uses methanol as a raw material,
It is an excellent catalyst for synthesizing hydrocarbons mainly composed of gasoline fractions having up to 10 carbon atoms, and has a long life as a catalyst and shows stable activity. Low selectivity. On the other hand, similarly, ZSM-34 has high selectivity to ethylene and propylene as a catalyst for producing lower olefins in the same reaction, but is abruptly deteriorated by carbon formation at high temperatures, which is not practical.

Therefore, under the present circumstances, a catalyst that suppresses activity deterioration due to carbon formation at high temperature, has a long catalyst life, and has excellent selectivity of lower olefins, particularly propylene, has not been obtained.

[Means for Solving Problems] The present inventor has conducted extensive studies in order to solve the above problems. As a result, by adding phosphorus and an alkaline earth metal salt in advance during hydrothermal synthesis of a mixture containing a silica source, an alumina source, an alkali metal source, etc., a large amount of alkaline earth metal that cannot be achieved by ordinary ion exchange is obtained. It has been found that a new zeolite containing can be obtained, and that this zeolite can solve the above-mentioned conventional problems.

That is, it has been widely known that the crystalline aluminosilicate is modified with an alkaline earth metal ion.
Usually, a method of carrying an alkaline earth metal ion on a proton (H ⁺ ) type crystalline aluminosilicate by ion exchange is used.

However, in this ion exchange method, it is difficult to support a large amount of alkaline earth metal ions, and a great deal of labor is required, which is not economical.

However, surprisingly, the present inventor can add a large amount of alkaline earth metal very easily by adding phosphorus and alkaline earth metal salt during the synthesis of crystalline aluminosilicate, Alkaline earth metal ions can be contained in an amount equal to or more than the isoelectric amount, and further, the zeolite catalyst thus obtained is a C ₂ -C ₄ lower olefin such as ethylene or propylene in the conversion reaction of methanol and / or dimethyl ether. It has been found that particularly, the selective production of propylene and the inhibition of carbon production are excellent, and therefore the durability of the catalytic activity is excellent.

Conventionally, in the production of crystalline aluminosilicate, coexistence of an alkaline earth metal salt in the starting material has been avoided because the arrangement of the crystal lattice is disturbed and the crystal growth is hindered, so that an amorphous product is likely to be produced. However, according to the study of the present inventor, when a tetrapropylammonium compound is used as a crystallization modifier, a higher Si content than that conventionally used when producing a ZSM-5 type crystalline aluminosilicate is used.
By adopting the O ₂ / Al ₂ O ₃ ratio, it is possible to obtain a crystalline aluminophosphosilicate without any trouble even if a large amount of phosphorus and an alkaline earth metal salt are present in advance in the raw material for producing an aluminosilicate crystal. It has been found that this crystalline aluminophosphosilicate exhibits an unexpectedly excellent catalytic activity, and the present invention has been achieved based on such findings.

That is, according to the present invention, firstly, the composition represented by the molar ratio of oxides is aM ¹ ₂ O · bM ² O · Al ₂ O ₃ · cP ₂ O ₅ · dSiO ₂ · nH ₂ O ... [I] Where M ¹ is an alkali metal and / or hydrogen atom, M ²
Is an alkaline earth metal, a is 0 to 2, b is 0.1 to 100, and c is 0.001 to
30, d is 12 to 3000, and n is 0 to 30. The present invention provides an alkaline earth metal-containing aluminophosphosilicate represented by

Secondly, the present invention has a second SiO ₂ / Al ₂ O ₃ molar ratio of 12 to 3000, SiO 2.
₂ / P ₂ O ₅ molar ratio of 5~1000, OH ^- / SiO ₂ molar ratio of 0.02 to 10, H ₂
O / SiO ₂ molar ratio of 1 to 2000, tetrapropylammonium compound / SiO ₂ molar ratio of 0.01 to 3, alkaline earth metal / Al atomic ratio of 0.03 to 300 The composition represented by the molar ratio of the oxide, which is characterized in that it is hydrothermally reacted with, provides a method for producing an alkaline earth metal-containing aluminophosphosilicate represented by the above formula [I].

Furthermore, the present invention thirdly uses the above-mentioned first alkaline earth metal-containing aluminophosphosilicate of the present invention as a catalyst in producing lower olefins by contacting methanol and / or dimethyl ether with the catalyst in a gas phase. The present invention provides a method for producing a lower olefin characterized by:

The first alkaline earth metal-containing aluminophosphosilicate of the present invention is ZSM- having a conventionally known pore size of 5 to 6 Å.
Although it is similar to that of 5 in the X-ray diffraction pattern, it is a novel substance having a higher alkaline earth metal / Al ratio than that and being distinguishable in catalytic activity. Further, the second method for producing an aluminophosphosilicate containing an alkaline earth metal of the present invention is distinguished from the conventional method in that phosphorus and an alkaline earth metal salt are present in the raw material at the time of production, and the obtained catalyst for zeolite is also present. The performance is also different from the conventionally known one.

The alkaline earth metal-containing aluminophosphosilicate according to the first aspect of the present invention is a novel zeolite and can be produced by various methods, but the one produced by the second method of the present invention is particularly preferable.

That is, in addition to the silica source, alumina source and alkali metal source used in the production of a usual zeolite catalyst,
A phosphorus source and an alkaline earth metal source are added in advance during hydrothermal synthesis, and this is hydrothermally reacted in an aqueous medium. In this case, it is preferable to add a crystallization modifier such as an organic amine, especially a tetrapropylammonium compound into the aqueous medium.

Here, water glass, silica sol, silica gel or silica powder can be used as the silica source, and water glass and silica sol are particularly preferably used. Next, as the alumina source, sodium aluminate, aluminum nitrate, aluminum sulfate, aluminum hydroxide, alumina sol, alumina and the like can be used, but sodium aluminate, aluminum nitrate, aluminum sulfate and aluminum hydroxide are preferable.

Phosphoric acid, sodium phosphate, sodium phosphate-hydrogen, sodium dihydrogen phosphate, phosphorus trichloride, etc. are used as the phosphorus source.

In addition, aluminum phosphate, hydrated aluminum phosphate or Berlinite (AlPO ₄ ) such as AlPO ₄ · nH ₂ O (n ≧ o)
The compound represented by the formula can also be used as an alumina source and a phosphorus source.

On the other hand, as the alkali metal source, sodium oxide, sodium aluminate, sodium hydroxide, potassium hydroxide, sodium chloride, potassium chloride, etc. in water glass are used.

Further, as the alkaline earth metal source, organic salts such as acetates and propionates of alkaline earth metals or chlorides,
An inorganic salt such as nitrate is used. Here, examples of the alkaline earth metal include magnesium, calcium, strontium, and barium. Particularly, calcium and strontium are preferable, and magnesium is preferable, and barium tends to require a high temperature for manifesting catalytic activity. Specific examples of the alkaline earth metal source include magnesium acetate, magnesium chloride, magnesium nitrate, calcium acetate, calcium chloride, calcium nitrate, strontium acetate, strontium chloride, strontium nitrate, barium acetate, barium chloride and barium nitrate. These may be used alone or in combination.

Crystallization modifiers include tetra-n-propylammonium bromide, tetra-n-propylammonium chloride, tetra-n-propylammonium iodide, a mixture of tri-n-propylamine and n-propylbromide, tetrapropyl hydroxide. Such as ammonium, especially tetra-bromide
N-propylammonium is preferred.

The composition of the reaction mixture for performing the hydrothermal reaction is prepared in the following proportions.

SiO ₂ / Al ₂ O ₃ (molar ratio): 10 to 3000, more preferably 4
0 to 1000 SiO ₂ / P ₂ O ₅ (molar ratio): _{5 to} 1000, more preferably 10
~500 OH ^- / SiO ₂ (molar ratio) (., Except hydroxyl ions from the organic base): 0.02 to 10, more preferably 0.05~0.5 H ₂ O / SiO ₂ (molar ratio): 1 to 2000 , And more preferably 5
500 Tetrapropyl ammonium compound / SiO ₂ (molar ratio): 0.01 to 3, more preferably 0.02 to 0.4 Alkaline earth metal / Al (atomic ratio): 0.03 to 300, more preferably 0.4 to 8 having the composition in the above range In order to obtain a mixture, the above-mentioned compounds were added, and if necessary, sulfuric acid, hydrochloric acid,
The pH of the system is adjusted to an appropriate value of 11 or less by adding an acid such as nitric acid or a hydroxide of an alkali metal.

The mixture thus obtained is heated at 80 to 250 ° C., preferably 150 to 180 ° C. under normal pressure or pressure for about 1 to 200 hours,
The hydrothermal reaction is preferably carried out for 5 to 50 hours, and in the case of 100 ° C. or lower, for about 1 to 30 days, preferably for 3 to 10 days, generally with heating and stirring.

The reaction product is separated by excess or centrifugation, washed with water to remove excess ionic substances, and then dried and calcined.

In this way, a crystalline aluminophosphosilicate containing an alkaline earth metal is obtained, but this crystalline aluminophosphosilicate contains an alkali metal oxide and an alkaline earth metal oxide, and by a conventional method, for example, hydrochloric acid or Hydrogen type substituted with protons (H ⁺ ) by ion exchange with inorganic acids such as sulfuric acid and nitric acid, organic acids such as formic acid and acetic acid, or ion exchange with ammonium compounds and then firing. Can be converted to crystalline aluminophosphosilicate. In this case, some or all of the alkali metals are easily replaced with protons (H ⁺ ), while the alkaline earth metals are only partially replaced with protons (H ⁺ ).

The conventionally known aluminosilicate modified with an alkaline earth metal is one in which an alkaline earth metal ion is introduced into a hydrogen type or an alkali metal type aluminosilicate by an ion exchange method, and in this case, the introduced alkaline earth metal is Ions can be converted into hydrogen form again by an ion exchange method and can be distinguished from the aluminophosphosilicate obtained by the method of the present invention. In other words, at least a part of the alkaline earth metal in the aluminophosphosilicate obtained by the method of the present invention is more strongly bound than the conventionally known alkaline earth metal-containing aluminosilicate.

Thus, the first alkaline earth metal-containing aluminophosphosilicate of the present invention having the composition represented by the above formula [I] and having a pore size of 5 to 6Å is obtained.

This product adsorbs linear or slightly branched paraffins such as n-hexane or 3-methylpentane, but does not adsorb 2,2-dimethylbutane, which is almost the same as that of ordinary ZSM-5 type zeolite. Pore size and adsorption capacity of ~ 6Å.

In order to use the above-mentioned aluminophosphosilicate obtained by the method of the present invention as a catalyst for producing a lower olefin from methanol and / or dimethyl ether, all or most of the alkali metal and part of the alkaline earth metal are protonated (H ⁺ The hydrogen form is usually substituted with).

This exchange is carried out by treating the compound with an aqueous solution of an ammonium compound, for example, an aqueous solution of ammonium chloride to exchange alkali metal ions for ammonium ions by utilizing a known ion exchange technique, and then expelling ammonia by calcination, or directly with hydrochloric acid or the like. It is also possible to convert to a proton type by treating. After being treated with an aqueous ammonium solution or hydrochloric acid, it is thoroughly washed with water, dried and baked. This firing is, for example, 1 to 100 at a temperature of 300 to 700 ° C.
It is achieved by processing time.

As mentioned above, some or all of the alkali metal ions are converted into protons (H ⁺ ) here, but the alkaline earth metal ions remain in this aluminophosphosilicate, and their catalytic performance is extremely high. The characteristic effect is exerted, which is different from the case where an alkaline earth metal is supported by a known ion exchange method.

Next, the third aspect of the present invention for producing a lower olefin from methanol and / or dimethyl ether by using the thus obtained first alkaline earth metal-containing aluminophosphosilicate of the present invention as a catalyst will be described.

When the above-mentioned first alkaline earth metal-containing aluminophosphosilicate of the present invention is used as a catalyst, it may be used as it is or, if desired, a suitable carrier such as clay, kaolin, alumina, silica or silica. -It can also be used by molding by mixing with alumina or the like.

The first alkaline earth metal-containing aluminophosphosilicate of the present invention can be used not only for producing olefins but also as a catalyst for decomposition, isomerization, alkylation, polymerization and the like.

The conversion reaction of methanol and / or dimethyl ether may be any reaction system as long as it can supply these raw materials as a gas and can sufficiently contact with a solid catalyst, and may be a fixed bed reaction system, a fluidized bed reaction system, or a mobile bed reaction system. A floor reaction system and the like can be mentioned.

The reaction can be carried out under a wide range of conditions. For example, the reaction temperature is 300 to 650 ° C, the weight hourly space velocity is 0.1 to 20 hr ^-1 , preferably ^{1 to} 10 hr ^-1 , the total pressure is 0.1 to 100 atm, preferably 0.5 to
It can be performed under the conditions of 10 atm. The raw material may be steam or an inert gas such as nitrogen or argon, or may be diluted with a hydrocarbon such as methane or propane and supplied onto the catalyst.

In a third method of the invention, the product stream is steam,
It is composed of hydrocarbons and unreacted raw materials, and the proportion of lower olefins such as ethylene and propylene in the hydrocarbons can be increased by appropriately setting the reaction conditions. Steam and hydrocarbon products are separated from each other by known methods,
Refined.

In the third method for producing a lower olefin of the present invention,
Since both methanol and dimethyl ether are starting materials, dimethyl ether generated from methanol may be regarded as an unreacted material when calculating the selectivity.

The synthesis reaction of a lower olefin from methanol and / or dimethyl ether according to the present invention is an exothermic reaction,
Since the temperature of the reaction system rises spontaneously, there is no particular problem in terms of energy consumption in carrying out the reaction at a high temperature, rather it is easier to control the temperature of the reaction system than to keep it at a low temperature, and the reaction rate increases. Therefore, there is also an advantage that a small reactor can be adopted. However, there is a problem in adopting a high temperature of 650 ° C. or higher on the material of the reactor, for example, the surface of stainless steel, and at a high temperature of 650 ° C. or higher, there is also a problem of catalyst crystal collapse due to water vapor existing in the reaction system. So
The upper limit of the reaction temperature actually adopted is limited to about 650 ° C.

Next, when the adsorbability of the alkaline earth metal-containing aluminophosphosilicate of the present invention is examined, among the hexane isomers, linear or slightly branched paraffins such as n-hexane or 3-methylpentane are adsorbed, 2,2
-Dimethylbutane has a unique shape selectivity that it does not adsorb.

Therefore, the alkaline earth metal-containing aluminophosphosilicate of the present invention is used in combination with small-pore zeolites such as erionite and offretite, and faujasite-type X and Y.
It is considered to be a new zeolite with a pore size intermediate to that of large pore size zeolites such as type.

[Examples] Next, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto unless it exceeds the gist thereof.

Preparation Example 1 Tetra-n-propylammonium bromide (TPABr) 7.82
g, 0.74 g of aluminum phosphate, 2.68 g of calcium acetate and 2.22 g of sodium hydroxide were sequentially dissolved in 170 g of water.
Next, water glass (SiO ₂ 30-31%, Na ₂ O 0.37-0.46%,
Catalyst Chemical Co., Ltd. colloidal silica Cataloid SI-3
0) 60 g was added and sufficiently stirred to obtain an aqueous gel mixture. The raw material composition is shown in Table 1.

This aqueous gel mixture was charged into a 300 ml autoclave and subjected to hydrothermal treatment under self-pressure at 160 ° C. for 16 hours while stirring at 500 rpm. The reaction product is separated into a solid component and a solution part by using a centrifuge, and the solid component is sufficiently washed with water, and further 120
It was dried at ℃ for about 7 hours.

Next, after treating in air at 530 ° C. for about 5 hours, 1 g of the calcined Na-type zeolite was mixed with 13 ml of a 5% ammonium chloride aqueous solution, and the mixture was stirred at room temperature for 1 hour. After that, wash thoroughly at room temperature with water, then dry at 120 ° C, then
It was calcined in the air at 00 ° C. for about 3 hours and converted into hydrogen form to obtain H form of calcium-containing aluminophosphosilicate. The crystal particle size of this H-type aluminophosphosilicate, B
Secondly the results of elemental analysis by ET specific surface area and fluorescent X-ray method
Shown in the table. The Na-type X-ray diffraction pattern is shown in FIG.

Preparation Examples 2,6,7,9 An H-type alkaline earth metal-containing aluminophosphosilicate was prepared in the same manner as in Preparation Example 1 except that the raw material composition was changed to the amounts shown in Table 1. Got However, the conversion to H-type zeolite of Preparation Example 7 was performed using hydrochloric acid. That is, 0.6 N hydrochloric acid was mixed at a ratio of 13 ml to 1 g of Na-type zeolite and stirred at room temperature for 24 hours.

The X-ray diffraction pattern of this Na-type zeolite was almost the same as that shown in FIG.

Preparation Examples 3 to 5 Preparation Example 1 except that a 500 ml quartz container was used in place of the autoclave and stirring was performed under normal pressure for 7 days while the composition of the raw materials was adjusted to the amounts shown in Table 1.
A calcium-containing aluminophosphosilicate was obtained in the same manner as in. The X-ray diffraction pattern of the obtained Na-type zeolite was almost the same as that shown in FIG. In Preparation Example 5, 3.35 g of calcium chloride was used instead of calcium acetate, and conversion to H-type zeolite was performed using hydrochloric acid as in Preparation Example 7.

Preparation Example 8 A strontium-containing aluminophosphosilicate was obtained in the same manner as in Preparation Example 3 except that strontium acetate was used in place of calcium acetate and the raw material composition was changed to the amount shown in Table 1. . The conversion to H-type zeolite was performed using hydrochloric acid as in Preparation Example 7. The X-ray diffraction pattern of the Na-type zeolite obtained here was almost the same as that shown in FIG.

Preparation Example 10 In Preparation Example 1, aluminum sulfate 16-18 hydrate was used in place of aluminum phosphate and calcium acetate, respectively.
H-type calcium-containing aluminophosphosilicate was obtained in the same manner as in Preparation Example 1 except that 96 g, phosphorus trichloride 0.53 g and anhydrous calcium chloride 1.69 g were used, and sodium hydroxide 2.99 g was further used. The conversion to H type was carried out using hydrochloric acid as in Preparation Example 7. The X-ray diffraction pattern of the Na-type zeolite obtained here was almost the same as that shown in FIG.

Preparation Example 11 Preparation Example 1 except that 1.14 g of aluminum nitrate nonahydrate and 3.51 g of phosphoric acid were used in place of aluminum phosphate, and further 1.34 g of calcium acetate and 2.61 g of sodium hydroxide were used. An H-type calcium-containing aluminophosphosilicate was obtained in the same manner as in. It was obtained
The X-ray diffraction pattern of Na-type zeolite was almost the same as that shown in FIG.

Preparation Example 12 Preparation Example 12 except that in Preparation Example 1, 1.14 g of aluminum nitrate nonahydrate was used in place of aluminum phosphate, and the composition of the raw materials was adjusted to the amount shown in Table 1 without adding calcium acetate. H type ZSM-5 was obtained in the same manner as in 1. The conversion to H-type zeolite was performed using hydrochloric acid as in Preparation Example 7.

Preparation Example 13 Preparation Example 13 except that 0.75 g of aluminum nitrate nonahydrate was used in place of aluminum phosphate and the composition of raw materials was adjusted to the amount shown in Table 1 without adding calcium acetate. H type ZSM-5 was obtained in the same manner as in 1.

Next, ion exchange was performed with calcium ions by a conventional method. That is, 40 ml of a 1N CaCl ₂ solution was added to 5 g of the above ZSM-5 at the beginning, and the mixture was stirred in an oil bath equipped with a reflux condenser and adjusted to 80 ° C. The replacement liquid is removed by decantation about every 3 hours, and a new replacement liquid 30
ml was added. After repeating this operation 20 times, thoroughly wash with water until Cl ⁻ ions are no longer observed, dry, and then 500
Calcination was performed for 3 hours to obtain calcium-exchanged ZSM-5.
The ion exchange rate of calcium was 45% according to the analysis result by the atomic absorption method. The conversion to H-type zeolite was performed using hydrochloric acid as in Preparation Example 7.

Preparation Example 14 Preparation Example 14 except that 2.78 g of aluminum nitrate nonahydrate was used in place of aluminum phosphate, and the raw material composition was adjusted to the amount shown in Table 1 without adding calcium acetate. H type ZSM-5 was obtained in the same manner as in 1.

Next, calcium modification was performed with reference to the description of JP-A-56-133223. That is, 4.5 g of calcium acetate is added to 20
ZSM-5 (6 g) was added to the solution dissolved in ml, and the mixture was stirred for 4 hours in an oil bath equipped with a reflux condenser and adjusted to 80 ° C. After washing with water, drying, and baking at 500 ° C. for 3 hours, calcium-modified ZSM-5 was obtained.

Conversion to H-type zeolite was performed using hydrochloric acid as in Preparation Example 7.

Preparation Examples 15 and 16 Preparation Example 1 except that the preparation composition of the raw materials was changed to the amount shown in Table 1 without adding calcium acetate.
An H-type zeolite was obtained in the same manner as in. It was obtained
The X-ray diffraction pattern of Na-type zeolite was almost the same as that shown in FIG.

Preparation Example 17 An H-type Ca-containing zeolite was prepared in the same manner as in Preparation Example 1 except that aluminum nitrate was used in place of aluminum phosphate and the composition of the raw materials was set to the amount shown in Table 1. Obtained. Conversion of H-type zeolite was performed using HCl as in Preparation Example 7. The X-ray diffraction pattern of the obtained Na-type zeolite was almost the same as that shown in JP-A-59-97523.

Table 2 collectively shows the crystal grain size, the BET specific surface area, and the elemental analysis result by the fluorescent X-ray method of the H-type zeolites obtained in Preparation Examples 1 to 12 and 14 to 17 by a scanning electron microscope.

Examples 1 to 11 and Comparative Examples 1 to 5 The zeolite powders obtained in Preparation Examples 1 to 16 were pressured at 400 kg / cm.
1 g of the mixture was tabletted in ² , crushed, and crushed to 12 to 24 mesh, and charged into a quartz reaction tube having an inner diameter of 10 mm. Then, liquid methanol was sent to the vaporizer at a rate of 4 ml / hr and 40
The mixture was mixed with argon gas, which is an internal standard gas sent at ml / min, and sent to the reaction tube at about atmospheric pressure, and the reaction was carried out at 340 to 600 ° C. The reaction was started at 340 ° C. and the temperature was raised stepwise to 600 ° C. every 2 hours.

Moreover, the analysis of the product was performed using a gas chromatograph. The results are shown in Table 3. Further, details of the results obtained in Examples 1, 3, 4, 6, 7, 9 and Comparative Examples 1, 2, 4, 5 are shown in Tables 4 to 1.
Each is shown in Table 3.

From Tables 3 to 13, it can be seen that the alkaline earth metal-containing aluminophosphosilicate obtained by the method of the present invention gives higher ethylene + propylene yield, especially propylene yield, and higher temperature than the zeolite catalyst of Comparative Example. It maintains high catalytic activity without deterioration even in the range, has little decomposition into CO, CO ₂ and methane, and has less by-products of aromatics, which are considered to be the cause of carbon formation, and suppresses carbon deposition on the catalyst. It is understood that

Example 12, Comparative Example 6 The Ca-containing aluminophosphosilicate of Preparation Example 10 and the Ca-containing zeolite powder of Preparation Example 17 were each pressure 400 kg / cm ^2.
1 cc (0.58 g) obtained by crushing with a tablet, crushed and aligned to 12 to 24 mesh was filled in a quartz reaction tube having an inner diameter of 10 mm.

Next, liquid methanol is sent to the vaporizer at a rate of 4 ml / hr, mixed with argon gas, which is an internal standard gas sent at 40 ml / min, and sent to the reaction tube at almost normal pressure, and accelerated life test at 600 ° C. I went. The reaction was performed by introducing methanol at 400 ° C and gradually raising the temperature to 600 ° C.

Moreover, the analysis of the product was performed using a gas chromatograph. The results are shown in Table 14.

In Ca-containing zeolite (JP-A-59-97523), the higher the Ca content in the zeolite, the longer the life,
As shown in Table 2, the Ca-containing aluminophosphosilicate of the present invention has substantially the same SiO ₂ / Al ₂ O ₃ ratio and particle diameter as those of the Ca-containing zeolite, that is, Comparative Example 6, and
Despite the low Ca content, it is clear that, as shown in Table 14, a life longer than twice as long can be obtained.
This is considered to be because the Ca-containing aluminophosphosilicate of the present invention has a smaller amount of BTX (benzene, toluene, xylene), which is considered as a precursor for carbon generation, as compared with the Ca-containing zeolite, and thus has a long life.

EFFECTS OF THE INVENTION The first alkaline earth metal-containing aluminophosphosilicate of the present invention is a novel zeolite containing a large amount of alkaline earth metal that cannot be achieved by ordinary ion exchange.
This product can be used for various purposes such as a catalyst and an adsorbent.

Furthermore, according to the second aspect of the present invention, such an alkaline earth metal-containing aluminophosphosilicate can be efficiently produced.

Further, the first alkaline earth metal-containing aluminophosphosilicate of the present invention thus obtained is excellent in thermal stability, and its structure is not changed even by heat treatment at about 900 ° C. Therefore, it is extremely convenient for pretreatment and regeneration as a practical catalyst.

Moreover, according to the third aspect of the present invention in which the first alkaline earth metal-containing aluminophosphosilicate of the present invention is used as a catalyst, carbon generation on the catalyst at high temperature and decomposition into CO and CH ₄ are suppressed, Lower olefins such as ethylene and propylene can be produced from methanol and / or dimethyl ether in a stable state for a long period of time with high selectivity and high yield.

Therefore, the present invention is widely and effectively utilized in the fields of petroleum refining and petrochemical industry.

[Brief description of drawings]

FIG. 1 is an X-ray diffraction pattern of Na-type calcium-containing aluminophosphosilicate obtained in Preparation Example 1 of the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kunio Suzuki, 1-1, Higashi, Yatabe-cho, Tsukuba-gun, Ibaraki Prefectural Chemical Research Institute (72) Inventor Haruo Takaya, 1-1, Yatabe-cho, Tsukuba-gun, Ibaraki Chemical Research In-house

Claims (12)

[Claims] 1. A composition expressed in molar ratios of oxides _{^{is, aM 1 2 O · bM 2}} O · Al 2 O 3 · cP 2 O 5 · dSiO 2 · nH 2 O ( wherein, M ¹ is an alkali metal And / or hydrogen atom, M ²
Is an alkaline earth metal, a is 0 to 2, b is 0.1 to 100, and c is 0.001 to
30, d is 12 to 3000, and n is 0 to 30. ) Alkaline earth metal-containing aluminophosphosilicate represented by: 2. The alkaline earth metal-containing aluminophosphosilicate according to claim 1, wherein the alkaline earth metal is calcium, strontium or magnesium. 3. The alkaline earth metal-containing aluminophosphosilicate according to claim 1 or 2, wherein b is 0.8 to 10, c is 0.004 to 7 and d is 40 to 1000. . 4. A SiO ₂ / Al ₂ O ₃ molar ratio of 12 to 3000, a SiO ₂ / P ₂ O ₅ molar ratio of ₅ to 1000, an OH ⁻ / SiO ₂ molar ratio of 0.02 to 10, H ₂ O / SiO. ₂ molar ratio 1-2000, tetrapropylammonium compound / Si
O ₂ molar ratio 0.01 to 3, alkaline earth metal / Al atomic ratio 0.03
The composition represented by the molar ratio of the oxides is characterized by hydrothermally reacting the raw material satisfying the composition of ~ 300 at a temperature of 80 ~ 250 ° C, aM ¹ ₂ O ・ bM ² O ・ Al ₂ O ₃・cP ₂ O ₅ · dSiO ₂ · nH ₂ O (In the formula, M ¹ is an alkali metal and / or hydrogen atom, M ²
Is an alkaline earth metal, a is 0 to 2, b is 0.1 to 100, and c is 0.001 to
30, d is 12 to 3000, and n is 0 to 30. ) A method for producing an alkaline earth metal-containing aluminophosphosilicate represented by: 5. The method according to claim 4, wherein the alkaline earth metal is calcium, strontium or magnesium. 6. The method according to claim 4 or 5, wherein b is 0.8 to 10, c is 0.004 to 7 and d is 40 to 1000. 7. The method according to claim 4, wherein the aluminophosphosilicate composition has an alkaline earth metal / Al atomic ratio of 0.4 to 8. 8. In the composition of aluminophosphosilicate
The manufacturing method according to claim 4, wherein the SiO ₂ / P ₂ O ₅ molar ratio is 100 to 10,000. 9. When a lower olefin is produced by bringing methanol and / or dimethyl ether into contact with a catalyst in a gas phase, the composition of the catalyst represented by the molar ratio of oxides is aM ¹ ₂ O.bM ² O. Al ₂ O ₃ · cP ₂ O ₅ · dSiO ₂ · nH ₂ O (In the formula, M ¹ is an alkali metal and / or hydrogen atom, M ²
Is an alkaline earth metal, a is 0 to 2, b is 0.1 to 100, and c is 0.001 to
30, d is 12 to 3000, and n is 0 to 30. ) A method for producing a lower olefin, which comprises using an aluminophosphosilicate containing an alkaline earth metal represented by 10. The alkaline earth metal is calcium, strontium or magnesium.
A method for producing a lower olefin according to the item. 11. The method for producing a lower olefin according to claim 9 or 10, wherein b is 0.8 to 10, c is 0.004 to 7 and d is 40 to 1000. 12. The method for producing a lower olefin according to claim 9, wherein the SiO ₂ / P ₂ O ₅ molar ratio is 100 to 10,000.