JPS58110421A - Crystalline iron aluminosilicate - Google Patents

Abstract

PURPOSE:To provide crystalline iron aluminosilicate having a specified composition and suitable for use as a catalyst in the manufacture of a lower olefin from methanol and/or dimethyl ether. CONSTITUTION:This crystalline iron aluminosilicate is represented by the formula (where M is H or an alkali metal; a=0.9+ or -0.3; b+c=1; c/b=0.3-10; d= 10-500; and n=0-200). The aluminosilicate is manufactured by hydrothermally reacting sources for feeding SiO2, Fe2O3, Al2O3 and alkali metallic ion in an aqueous medium contg. alcohol.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel crystalline iron aluminone liquede and a catalyst for producing lower olefins from methanol and/or dimethyl ether containing the same as an active ingredient.

Various types of crystalline silicates have been known so far, and among them, crystalline alumino/licade zeolite is the most representative. It has the function of excluding substances higher than crystalline aluminum, and is also called a molecular sieve. Pores due to voids and tunnels are determined by the form in which 840□ and Al2O3 bond together by sharing oxygen in the crystal structure. The electronegativity of the aluminum-containing tetrahedrons is usually kept electroneutral by alkali metal ions, especially sodium and/or potassium.

Usually, to produce crystalline aluminosilicate zeolite, 8 + 02, AZ 203, alkali metal ion sources and water are mixed in the desired proportions, and hydrothermal treatment is performed under normal pressure or pressurization. is taken.

There is also a method of using organic nitrogen compounds or organic phosphorous compounds as bases, and various zeolites with various adsorption capacities and catalytic activities have been synthesized using this method, and the synthesis of these types of zeolites has become very popular in recent years. . Especially ZSM by Mopil Oil. Among them, ZSM-5
has a medium pore size of 5 to 6 people, so it has the property of adsorbing linear hydrocarbons and slightly branched hydrocarbons, but not adsorbing highly branched hydrocarbons. It is effective as a catalyst for catalytic dewaxing, cracking, isomerization, alkylation, polymerization, and especially for producing gasoline from methanol. This ZSM-5 is usually 8i02, AI! It is synthesized by hydrothermally treating a mixture consisting of R03, each supply of alkali metal, water, and a tetra-n-propylammonium compound.

Research into obtaining hydrocarbons by reacting methanol and/or dimethyl ether has been very active in recent years. The catalyst used in this reaction is generally what is called a solid acid, and many patents have been filed regarding various zeolites, heteropolyacids, etc. In particular, it is unsuitable for producing lower olefins such as ethylene and propylene produced by Mopil Oil. Also, similarly Z
SM-34 has high selectivity to ethylene and propylene as a catalyst for producing lower olefins in the same reaction, but its activity decreases extremely quickly and is not practical.

As a result of extensive research into the development of a catalyst that selectively produces hydrocarbons, particularly lower olefins such as ethylene and propylene, using methanol and/or dimethyl ether as a raw material, and has stable activity, the Formula% Formula% (In the formula, M is an alkali metal or hydrogen atom, a is 0.9±
0.3, the sum of b and C is 1, and c /b is 0.3
~lO1 is preferably 1 to 5, d is a number of lO~500 and n is θ~200)8i0□+Fe2O3ν
It is produced by hydrothermally reacting sources of Aj, O, and alkali metal ions in an aqueous medium. In this case, additives and alcohol are added to the aqueous medium. By adding this alcohol, a crystalline iron aluminosilicate having a catalyst structure suitable as a catalyst for olefin synthesis can be obtained.

Next, the method for producing crystalline iron aluminosilicate according to the present invention will be described in more detail.

As the SiO2 source, water glass, 7-hydrosol, silica gel, and silica can be used, and water glass and 7-lika sol are preferably used. Water-soluble ferric salts can be used as the Fe2O3 source, and preferred examples include ferric nitrate and ferric ammonium sulfate. A7?20. As a source, aluminum (aluminum/acid), aluminum sulfate, alumina sol, alumina, etc. are used. The alcohol added to the aqueous medium is preferably a straight chain n-alcohol having 1 to 8 carbon atoms, such as n-propyl alcohol,
Particularly preferred is n-butyl alcohol.

The composition of the reaction mixture to be subjected to hydrothermal treatment is preferably prepared in the following proportions.

sto2/Fe203 (molar ratio): 20-1000, more preferably 30-500 Sto2/Aj203 (molar ratio): 20-500
〃50~400 S'0J (Fe20s + Al2O; X molar ratio): 10~
500, more preferably 20 to 3000H/SiO, (
molar ratio): 0.05 to 1.0 1/
0.1-0,75H2010H (molar ratio):
lO~300 // 30~250RO
H/5iO2 (molar ratio): 0.1-5
1/0.5 to 4 In order to obtain a mixture having a composition within this range, an acid such as hydrochloric acid, sulfuric acid, nitric acid or an alkali metal hydroxide is added as appropriate.

This mixture is heated to 120-220°C, preferably 150-1
At 90° C. for about 1 to 200 hours, preferably 5 to 50 hours, a crystalline iron aluminosilicate is thus obtained, which is an alkali metal salt (in the above formula M=
Alkali metal). This alkali metal salt type crystalline iron aluminosilicate can be prepared by a conventional method, for example.
By reacting with an inorganic acid such as hydrochloric acid, sulfuric acid, or nitric acid, or an organic acid such as formic acid or acetic acid, or by reacting with an ammonium salt and then firing, some or all of the alkali metals can be converted into protons (H+). The crystalline diffraction pattern of the substituted hydrogen type is shown, and Table 2 shows the X-ray diffraction pattern of the hydrogen type crystalline iron aluminosilicate in which the sodium ions are replaced with protons. Note that these diffraction data are relative values when copper is irradiated with alpha rays at 100%.

Margin table below -l [X-ray diffraction of crystalline iron aluminosilicate (Na type])
Table 2 [X-ray diffraction of crystalline iron aluminosilicate (hydrogen type)]
Comparing these X-ray diffraction peaks with those of ZSM-5 specified in Japanese Patent Publication No. 46-10064, 2
The strongest peak 2θ = 23.14 of 8M-5 is 2θ = 23.00 and 23.20 in this crystalline iron aluminosilicate.
exist and are clearly distinguished. Also low angle 20=
When comparing the two peak intensities of 7.75-7.85 and 8.65-8.80, the former peak is stronger in ZSM-5, whereas the one obtained with this crystalline iron aluminosilicate is clearly Divided into two and at a low angle 20 = 23.6
The peak of 0-23.65 is 23.80-23.85
larger than that of This tendency is true for both the product immediately after synthesis and the product converted to the hydrogen form. In general, ZSM-5 uses the dried product immediately after synthesis and the X
Comparing the line diffraction patterns, the low angle 20 = 7.9 ~
The two peaks at 8.9 tend to become larger in the latter case, but in this crystalline iron alumino hepta-silicate zeolite, the phenomenon that the peak intensity of the calcined product is higher than that of the dry product is hardly observed. . However, in many other respects it is similar to the ZSM-5 pattern.

In the crystalline iron-aluminum non-licade of the present invention, iron ions substitute silicon in the same way as aluminum ions. This confirms that the distance between the (804) planes is widened due to the following. Immediately
As a sample, Si
Using 28M-5 prepared with different O2/A/201 molar ratios and the product of the present invention, these samples were thoroughly mixed with 99.99% silicon to be used as an internal standard, and the X-ray diffraction peak of this mixture was , 2# based on the (804) plane is 45
．． Accurately read the peak near 0 degrees while comparing it with the peak 2θ=47.3 degrees of the (220) plane of silicon. (8
04) 5in2/AI peak position based on surface! 203
As a result of measurement in correspondence with the molar ratio, in ZSM-5, as the aluminum content increases, i.e., Si02/A
It is confirmed that as the l2O's molar ratio decreases, the peak position of the (804) plane shifts to a lower angle and the interplanar spacing widens; This indicates that iron ions, which have a larger ionic radius than aluminum ions, substitute silicon and enter the crystalline silicate lattice, further expanding the interplanar spacing.

(2) In the case of a crystalline silicate having this type of structure, when the amount of elements substituting silicon increases, the monoclinic system changes to the orthorhombic system. The difference between the monoclinic system and the orthorhombic system is that in the X-ray diffraction peak, the 2θ of the orthorhombic system is 24.
While there is one peak each around 3 degrees and around 29.2 degrees, in the monoclinic system, each peak is divided into two, which are identified. The product according to the present invention (product of Example 1) exhibits a monoclinic crystal system, whereas the product without Fe2O source (product of Comparative Example 1) exhibits a monoclinic system, whereas
Although it contains few components, it is an orthorhombic crystal thread.

This is because iron ions, like aluminum ions, substitute silicon and enter the lattice, and AJ20.
Despite the small amount of ingredients, the amount of acid is clearly large (Table 3
(See table 6). This indicates that iron ions are also included in the lattice.

Next, when examining the adsorption properties of the crystalline iron aluminosilicate of the present invention, the product of the present invention adsorbs n-hexane best among hexane isomers, and also adsorbs 3-methylpentane, which has one methyl group. However, 2-2-dimethylbutane, which has two methyl groups, has unique shape selectivity in that it is hardly adsorbed. Therefore, the crystalline iron aluminosilicate of the present invention is suitable for small pore size zeolites such as erionite and offretite and faujasite type X and y.
It is considered to be a zeolite with a pore size intermediate to that of d-zeolite.

The product of the present invention has excellent thermal stability, 9o.

By using the crystalline iron aluminosilicate obtained by the method of the present invention as a catalyst, hydrocarbons and lower olefins such as ethylene and propylene can be produced from methanol and/or dimethyl ether with high selectivity and stable activity. .

The crystalline iron aluminosilicate used as a catalyst in the present invention is preferably a hydrogen type in which alkali metal ions as cations after synthesis are wholly or partially converted into protons by an ion exchange method. This exchange can be carried out using known ion exchange techniques by treating with an aqueous ammonium solution, such as an aqueous ammonium chloride solution, to exchange alkali metal ions with ammonium ions, followed by calcination to drive out ammonia and convert it into protons.

It is also possible to convert it into protons by direct treatment with an aqueous hydrogen chloride solution. After treatment with an aqueous ammonium solution or an aqueous hydrogen chloride solution, this is achieved by a sufficient amount.

The conversion reaction of methanol and/or dimethyl ether is
Any reaction method may be used as long as these raw materials are supplied as a gas and can be brought into sufficient contact with a solid catalyst, such as a fixed bed reaction method, a fluidized bed reaction method, and a moving bed reaction method.

The reaction can be carried out under a wide range of conditions.

For example, reaction temperature 250-450℃, weight time space velocity 0
．． It can be carried out under conditions of 1 to 20 hr-', preferably 1 to 10 hr', and a total pressure of 0.1 to 100 atm, preferably 0.5 to 10 atm. The raw material can also be diluted with water vapor or an inert gas such as nitrogen, argon, etc. and then fed onto the catalyst.

In the process of the present invention, the product stream consists of steam, hydrocarbons and unreacted raw materials, which are separated and purified from each other by ethylene and hydrogen in the hydrocarbons by appropriately setting the reaction conditions.

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

Example 1 A
Liquid and No. 4 water glass (Si0□24%, Na206.
5%) 61.1f was dissolved in water 64F and this was used as liquid B. Add liquid B to liquid A while stirring vigorously, and then
A 2.5N sulfuric acid aqueous solution 24-mL was added thereto, and 16.2 F of n-butylalcocel was further added thereto, and stirring was continued for about 10 minutes even after the addition was completed to obtain an aqueous gel mixture.

The molar ratio of 5IO2/Fe2O3 in the preparation was 98, and S i0
2/Aj203 molar ratio is 195 + S 102/ (
Fe203+A#203) molar ratio was 65. It was dried at aqueous temperature in an autoclave with an internal volume of 300 °C. The yield of the product obtained was approximately 14f. Observation using a scanning electron microscope confirmed that no other zeolites or gels coexisted in this product. Since the crystal size was 1 to 3 μm, the treatment was carried out for 5 hours. The specific surface area was measured based on the BET method and was 280.4 m''/f.
Quantitative analysis of iron content using fluorescent X-ray method 8i
o.

against re20. was 3.6% by weight.

Next, this calcined crystalline iron aluminosilicate 11 was mixed with 30 - of a 0.6N aqueous hydrogen chloride solution and stirred at room temperature for 10 hours, which was repeated twice in total to remove sodium ions. converted into protons. After washing thoroughly with water at room temperature, the amount of ammonia adsorbed was measured using a quartz spring balance. First, the sample was evacuated at 450°C for 2 hours to completely remove the adsorbate, then placed in an ammonia atmosphere at 1 s torr for 1 hour at 100°C, and then evacuated at 100°C for 1 hour to remove the adsorbed material. Then, the sample temperature was raised at a rate of 10° C./min, and the amount of ammonia adsorbed at each temperature was observed. The results are shown in Table-3.

Table 3 Minosilicate powder was compressed into tablets at a pressure of 400 and 97:2,
Next, this was crushed into powder and arranged into 10 to 20 meshes 2-, which was filled into a reaction tube with an inner diameter of 10 mm. Liquid methanol is sent to the vaporizer at a rate of 2d/hr, where 10
The mixture was mixed with argon gas fed at a rate of d/min and sent to a reaction tube, where a reaction was carried out at 300°C. Analysis of the product was performed using a gas chromatograph.

The results are shown in Table 4.

Table 4 *l Yield of carbon paste relative to supplied methanol All experiments were carried out in the same manner as in Example 3, except that the core tube was filled with 1. The reaction results are shown in Table-5.

As is clear from the results shown in Table 5 above, when crystalline iron aluminone ricade according to the method of the present invention is used as a catalyst,
It was dissolved in extremely high ethylene and propylene 641, and this was used as liquid B. Solution B was added to solution A with vigorous stirring, and then 2.5% of the aqueous gel mixture was thus treated in the same manner as in Example 1 to obtain the amount of crystalline aluminolicade. The measurement results are shown in Table-6.

Table-6 4 Example 2 ,-,,,%-Bill Oil Ltd. British Patent 140298
Example No. 1: Crystalline iron silicate was prepared based on the reference.

-Water 57. 1.55f of ferric nitrate nonahydrate in Ill
.

Concentrated sulfuric acid 2.81? , 16.2 t of potassium chloride was dissolved to obtain liquid A. Water 42.3 f with No. 3 water glass (Sin
, 29%, Na, O 9.5%) 33.8 t was dissolved to prepare B solution. Add liquid B dropwise to liquid A while stirring, and after stirring thoroughly, add IJ fi-propylamine 247.
A mixed solution of f and n-propyl bromide (1.90%) was added to obtain an aqueous gel mixture. Preparation 8i0. /Fe, O, molar ratio was 85.

The aqueous gel mixture was charged into an autoclave with an internal volume of 300 m1, and stirred at 160°C for 16 hours under autoclaved pressure (50 m1).
0r, p, m,) hydrothermally treated. The reaction mixture was separated into a solid component and a solution part using a centrifuge, and the solid component was thoroughly washed with water and further dried at 120°C.

The yield of the product obtained was about 9.5 tons. When analyzed by X-ray diffraction, the pattern was similar to that described in Patent Publication No. 10064/1983 or British Patent No. 1402981.
t matched. The results are shown in Tables 8 and 9 regarding the activity of this crystalline iron 7 silicate.

Margin Table -8 Table -9 Shows the X-ray diffraction pattern of crystalline aluminosilicate (Na salt type) that does not contain iron ions.

Procedural Amendment 57 Kagiken No. 15゜1 No. 1, Indication of Case 1981 Patent Application No. 2゜6.
87 No. 2. Title of the invention: Crystalline iron aluminosilicate 3. Patent applicant address related to the amended person's case: 1-3-1 Kasumigaseki, Chiyoda-ku, Tokyo. (114) Director of the Agency of Industrial Science and Technology (' f ” ゞ(4
f Makoto Ishiita - 7. Symmetry of the amendment Column 8 of the detailed explanation of the invention in Particulars +'lJ: Contents of the amendment The sleeve of the specification of the present application - 1 is corrected as follows.

(1) Add the following sentence after line 15 of item 24.

[Example 4 Ferric nitrate nonahydrate 2.02 g1 aluminum nitrate 16
~ 0.41 g of 18 hydrate was dissolved in 86.4 g of water to make solution A, and 61.1 g of No. 14 water glass was dissolved in 63.4 g of water.
This was designated as liquid B. B in A liquid while J'i bond violently
Add the solution and then add 24ml of 2.5N nitric acid aqueous solution to this.
Furthermore, 18.4 g of n-butyl alcohol was added, and a gel mixture was obtained for about 10 minutes even after the addition of 18.4 g was completed. The charged Sin,/Fe,O, molar ratio was 98,
SiO = / AlzOs molar ratio is 390
, 5inJ/(F”e,O,+AIJO, ) molar ratio was 78. All operations were performed as in Example 1 except for preparing the aqueous gel mixture in this way. ) Washing with water) Drying The convergence of the crystalline iron aluminosilicate obtained was about 14 g.

The X-ray diffraction pattern almost matched those shown in Table 1 and Figure 1.

The specific surface area based on the BIT method was 5237.1 m'/g. Table showing the amount of ammonia adsorbed after conversion to hydrogen form.
7.

Table-7 Temperature ('C) NH, adsorption amount (mmol/g)
100 0, 57 150 0, 51 200 0, 39 250 0, 25 300 0, 09 350 0, 02 Example 5 All procedures were carried out except for using the crystalline iron aluminosilicate powder in the hydrogen form shown in Example 4. It was carried out in the same manner as in Example 2.

The methanol conversion reaction activity is summarized in Table-8.

Table-8 (32.0) (30.3) 3, 3 81.4 14.5 15
．． 4 (3 0, 2), (3 2, 1) 4, 3
81.3 13.0 12.7 (2
8.3) (27.6)

Claims (1)

[Claims] (1) Composition formula % Formula % (In the formula, M is an alkali metal or hydrogen atom, a is 0.9±
0.3, b and C have a total of 1, and c/b is 0.
3-10 te #s, d is 10-500. and n is 0 to 20
A crystalline iron aluminosilicate represented by: Composition formula % formula % (where M is an alkali metal or hydrogen atom, a is 0.9±
0.3, b and C have a total of 1, and c/b is 0.3~
lO tea, d is 10-500. and n is a number from θ to 200) A catalyst for converting lower olefins from methanol and/or dimethyl ether, consisting of a crystalline iron aluminosilicate represented by: