JPS6251889B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing crystalline aluminosilicate zeolite. More specifically, the present invention relates to a method for producing crystalline aluminosilicate zeolite from a raw material mixture containing silica, alumina, an alkali metal, water, and a specific heterocyclic compound. Crystalline zeolites, whether natural or synthetic, contain cations such as Na, K or H ions. These zeolites are SiO ₄
It is a three-dimensional network structure of AlO ₄ and SiO ₄ .
AlO ₄ is characterized by having a highly ordered tetrahedral structure cross-linked through oxygen atoms. Such crystalline zeolites have a large number of small pores within their crystal structure and are well known as molecular sieves, and are used for various purposes by taking advantage of this property. This crystalline zeolite is not only used in conversion reactions of various hydrocarbons, but also recently zeolite ZSM-5 or similar zeolite is used as a catalyst for producing hydrocarbons from synthesis gas via methanol and dimethyl ether. The method for producing zeolite is well known. The most well-known method for producing these zeolites is a method in which a tetraalkylammonium ion is added to a raw material composition consisting of silica, alumina, an alkali metal, and water to carry out a reaction. However, this method of adding tetraalkylammonium ions was not necessarily suitable as an industrial production method because it was expensive.
It has been proposed to use alkylamines, amino alcohols, ammonia, organic sulfur compounds, etc. as additives to overcome this drawback. As a result of extensive research into the raw material composition of the method for producing crystalline aluminosilicate zeolite, the present inventors found that when the raw material composition contains a specific heterocyclic compound, the resulting reaction product It was found that the X-ray diffraction pattern of ZSM-5 was similar to that of the above-mentioned known zeolite ZSM-5. The present invention has been made based on this knowledge. That is, the present invention provides a method for producing crystalline aluminosilicate zeolite from a raw material mixture consisting of silica, alumina, an alkali metal, water, and at least one heterocyclic compound selected from the group consisting of morpholine, oxazolidine, isoxazolidine, and derivatives thereof. This is a method for producing crystalline aluminosilicate zeolite, which is characterized by maintaining the crystalline aluminosilicate zeolite under the conditions of temperature and time necessary for the production of crystalline aluminosilicate zeolite. The X-ray diffraction pattern of the crystalline zeolite powder produced by the method of the present invention was very similar to that of the conventionally known zeolite ZSM-5. Therefore, it can be used in organic compound conversion processes, such as conversion reactions of hydrocarbon compounds and oxygen-containing compounds such as methanol. In the synthesis reaction of the present invention, a raw material mixture consisting of a silica source, an alumina source, an alkali metal source and water, which are used in the synthesis of ordinary crystalline zeolite, can be used, and the above-mentioned heterocyclic compound is further added to this mixture. It is done by doing. The silica source is not particularly limited as long as it is commonly used in the production of crystalline zeolite, and any silica powder, silicic acid, colloidal silica, dissolved silica, etc. can be used. Examples of dissolved silica include water glass silicates and alkali metal silicates containing 1 to 5 moles of SiO ₂ per mole of Na ₂ O or K ₂ O. The alumina source is not particularly limited as long as it is commonly used in the production of crystalline zeolite, and includes aluminum salts such as sulfates and nitrates, such as aluminum sulfate, sodium aluminate, colloidal alumina, and alumina. etc. are used. The ratio of silica to alumina in the raw material mixture of the present invention is desirably in the range of 10 to 500, preferably 20 to 200 in terms of SiO ₂ /Al ₂ O ₃ molar ratio. On the other hand, sodium hydroxide, potassium hydroxide, etc. are used as the alkali metal source. Furthermore, sodium silicate or sodium aluminate can also serve as a source of silica or alumina. Particularly preferred as the alkali metal is sodium, and this alkali metal is used as M ₂ O in a ratio of 0.01 to 50 mol, preferably 0.1 to 10 mol, per 1 mol of silica (SiO ₂ ). Next, as the heterocyclic compound used in the present invention, as mentioned above, morpholine, oxazolidine,
It is isoxazolidine or a derivative thereof, and examples of the derivative include N-aminopropylmorpholine and 2-methyloxazolidine.
These heterocyclic compounds used in the present invention include:
Water-soluble ones are advantageously used. The amount of the heterocyclic compound added in the present invention is determined in the range of 0.01 to 50 mol, preferably 0.1 to 10 mol, per 1 mol of silica ( _SiO2 ). In the present invention, a raw material mixture consisting of silica, alumina, an alkali metal, water, and the above-mentioned heterocyclic compound may be heated at a temperature and for a time necessary to form a crystalline aluminosilicate zeolite. Note that the amount of water is not particularly limited in the present invention. At this time, a mineralizing agent such as lithium chloride may be added to promote crystallization if necessary. The synthesis reaction of the present invention is carried out by heating the raw material mixture at a temperature and time necessary to produce crystalline zeolite, and more specifically, the reaction temperature is 80 to 300°C, preferably 120 to 300°C. 200℃
The reaction time ranges from 0.5 hours to 30 days,
Preferably it is 5 hours to 10 days. There are no particular restrictions on the pressure, and it is usually carried out under autogenous pressure.
Further, the reaction system is usually kept under stirring, and the atmosphere may be replaced with an inert gas if necessary. The synthesis reaction is continued by heating the raw material mixture to a desired temperature until sufficient crystalline zeolite is produced. After the reaction mixture in which the production of crystalline zeolite has been completed is cooled to room temperature, crystals are separated by filtration, decantation, centrifugation, etc., and thoroughly washed with water to obtain crystals. Crystalline aluminosilicate zeolite can be obtained by drying these crystals usually at 100°C or higher for several hours. In the present invention, before using this crystalline zeolite as a catalyst, it is activated by firing it in air at a temperature in the range of 300 to 700°C for about 2 to 48 hours, and the alkali metal ions present in the crystalline zeolite are activated. This includes a method of ion-exchanging part or all of the cation with at least one other cation to form H-type crystalline zeolite. This ion exchange method is a well-known technology in the industry.
Suitable cations include metal ions, ammonium ions, hydrogen ions, and mixtures thereof; examples of metal ions include cations of lithium, silver, magnesium, calcium, barium, aluminum, manganese, cobalt, nickel, or rare earth metals. be able to. These selections are arbitrarily determined depending on the type of conversion reaction. In the ion exchange method, the crystalline zeolite may be contacted with an aqueous solution containing a desired cation, and chlorides, nitrates, and sulfates of cations are usually used. After ion exchange, the crystalline zeolite is washed with water, dried, and then calcined in air or in an inert gas at a temperature of 300 to 700°C for 2 to 48 hours or more to form a catalytically active catalyst. becomes. The crystalline zeolite obtained by the method of the invention is of the same type as zeolite ZSM-5 and can be used, for example, in conversion reactions of hydrocarbon compounds and oxygen-containing compounds such as methanol. Such methods include alkylation of aromatic compounds with olefins; aromatization of olefins and paraffins; isomerization of aromatics, paraffins, and olefins; disproportionation of aromatics; oligomerization of olefins; and cracking. Further examples include methods for producing hydrocarbons from synthesis gas and methanol. As detailed above, the method of the present invention is inexpensive and
Moreover, it relates to an industrially advantageous method for producing crystalline zeolite, which can be used not only as a catalyst or catalyst support for the various conversion reactions mentioned above, but also for many other uses, such as adsorbents, extractants, and ion exchangers. This made it possible to provide crystalline zeolite suitable for use in molecular sieves, etc. The method of the present invention will be explained below with reference to Examples. Example 1 A solution containing 7.52 g of aluminum sulfate (18 hydrate), 8.7 g of morpholine, 17.6 g of sulfuric acid (97%), and 250 ml of water was used as solution A. 162g of water glass (37.6% by weight of SiO ₂ , 17.5% by weight of Na ₂ O, 44.9% by weight of water) and water
The solution containing 300ml is called Solution B. Solution C is a solution of 79 g of sodium chloride and 122 ml of water. While stirring Solution C, Solutions A and B were gradually added dropwise to it simultaneously at room temperature. This mixture was placed in autoclave No. 1, and reacted for 20 hours at 170° C. under autogenous pressure while stirring at a rotation speed of 200 rpm. After the reaction mixture was cooled, it was washed five times with 1 portion of water, and the solid content was separated by filtration and dried at 120° C. for 3 hours to obtain 53.2 g of crystalline aluminosilicate zeolite. This crystalline aluminosilicate zeolite
The results of the line diffraction diagram are shown in Table 1. In addition, this material has the following composition in molar ratio. 1.1 (Na ₂ O): 65.5 (SiO ₂ ): 1.0 (Al ₂ O ₃ )

[Table] Example 2 The zeolite obtained in Example 1 was used as Zeolite 1.
It was immersed in 5 ml of 1N ammonium nitrate aqueous solution per gram and stirred occasionally. After 24 hours, the supernatant liquid was removed and the sample was immersed in a fresh 1N ammonium nitrate aqueous solution for 24 hours. Thereafter, the solid content was separated by filtration, thoroughly washed with water, and then dried at 120°C for 3 hours to convert the sodium form into the ammonium (NH ₄ ⁺ ) form. Further, the mixture was calcined at 550° C. for 6 hours in an air stream to obtain an H-type aluminosilicate zeolite. Example 3 A solution containing 7.52 g of aluminum sulfate (18 hydrate), 7.3 g of oxazoline, 17.6 g of sulfuric acid (97%), and 250 ml of water was used as solution A. A solution of 162 g of water glass (37.6% by weight of SiO ₂ , 17.5% by weight of Na ₂ O, 44.9% by weight of water) and 300 ml of water is called liquid B. Solution C is a solution of 79 g of sodium chloride and 122 ml of water. While stirring Solution C, Solutions A and B were gradually added dropwise to it simultaneously at room temperature. This mixture was placed in an autoclave No. 1, and reacted for 20 hours at 170° C. under autogenous pressure while stirring at a rotation speed of 200 rpm. After the reaction mixture was cooled, it was washed five times with 1 portion of water, and the solid content was separated by filtration and dried at 120° C. for 3 hours to obtain 51.0 g of crystalline aluminosilicate zeolite. This crystalline aluminosilicate zeolite has the following composition in molar ratio: 1.1 (Na ₂ O): 63.4 (SiO ₂ ): 1.0 (Al ₂ O ₃ ) Example 4 Aluminum sulfate (18 hydrate) 18.5 g, isoxazolidine 7.3 g, sulfuric acid (97%) 17.6 g, water 250 ml
The solution obtained is called Solution A. A solution of 162 g of water glass (37.6% by weight of SiO ₂ , 17.5% by weight of Na ₂ O, 44.9% by weight of water) and 300 ml of water is called liquid B. Solution C is a solution of 79 g of sodium chloride and 122 ml of water. While stirring Solution C, Solutions A and B were gradually added dropwise to it simultaneously at room temperature. This mixture was placed in an autoclave No. 1, and reacted for 20 hours at 170° C. under autogenous pressure while stirring at a rotation speed of 200 rpm. After the reaction mixture was cooled, it was washed five times with 1 portion of water, and the solid content was separated by filtration and dried at 120° C. for 3 hours to obtain 51.5 g of crystalline aluminosilicate zeolite. This crystalline aluminosilicate zeolite has the following composition in molar ratio: 1.4 (Na ₂ O): 63.9 (SiO ₂ ): 1.0 (Al ₂ O ₃ ) Example 5 Aluminum sulfate (18 hydrate) 7.52 g, N-aminopropylmorpholine 12.0 g, sulfuric acid (97%) 17.6
g, a solution of 250 ml of water is called Solution A. Water glass (SiO ₂ 37.6 wt%, Na ₂ O 17.5 wt%, water
Solution B is a solution of 162 g (44.9% by weight) and 300 ml of water. Solution C is a solution of 79 g of sodium chloride and 122 ml of water. While stirring Solution C, Solutions A and B were gradually added dropwise to it simultaneously at room temperature. This mixture was placed in an autoclave No. 1, and reacted for 20 hours at 170° C. under autogenous pressure while stirring at a rotation speed of 200 rpm. After the reaction mixture was cooled, it was washed five times with 1 portion of water, and the solid content was separated by filtration and dried at 120° C. for 3 hours to obtain 54.5 g of crystalline aluminosilicate zeolite. This crystalline aluminosilicate zeolite has the following composition in molar ratio: 1.3 (Na ₂ O): 62.4 (SiO ₂ ): 1.0 (Al ₂ O ₃ ) Example 6 Aluminum sulfate (18 hydrate) 7.52 g, 2-methyloxazolidine 8.6 g, sulfuric acid (97%) 17.6 g,
A solution containing 250 ml of water is called Solution A. A solution of 162 g of water glass (37.6% by weight of SiO ₂ , 17.5% by weight of Na ₂ O, 44.9% by weight of water) and 300 ml of water is called liquid B. Solution C is a solution of 79 g of sodium chloride and 122 ml of water. While stirring Solution C, Solutions A and B were gradually added dropwise to it simultaneously at room temperature. This mixture was placed in an autoclave No. 1, and reacted for 20 hours at 170° C. under autogenous pressure while stirring at a rotation speed of 200 rpm. After the reaction mixture was cooled, it was washed five times with 1 portion of water, and the solid content was separated by filtration and dried at 120° C. for 3 hours to obtain 56.3 g of crystalline aluminosilicate zeolite. This crystalline aluminosilicate zeolite has the following composition in molar ratio: 1.3 (Na ₂ O): 65.5 (SiO ₂ ): 1.0 (Al ₂ O ₃ )

Claims (1)

[Claims] 1. Temperature necessary to produce crystalline aluminosilicate zeolite from a raw material mixture consisting of silica, alumina, an alkali metal, water, and at least one heterocyclic compound selected from the group consisting of morpholine, oxazolidine, isoxazolidine, and derivatives thereof. A method for producing a crystalline aluminosilicate zeolite, characterized in that it is kept under conditions of and time.