JPH0543644B2 - - Google Patents

Description

[Detailed description of the invention]

B. Object of the Invention <<Industrial Application Field>> The present invention relates to a crystalline aluminosilicate. More specifically, the present invention relates to a method for producing a binderless zeolite catalyst that is substantially free of binder. <<Prior art>> Crystalline aluminosilicate is generally known as crystalline zeolite, and its crystal structure, both naturally occurring and synthetic, is formed mainly of silicon (Si).
SiO ₄ tetrahedron with oxygen atoms coordinated at the vertices,
Aluminum (Al) replaced silicon
It is an aluminosilicate hydrate with a structure based on a three-dimensional framework of AlO ₄ tetrahedra. SiO ₄ tetrahedron and AlO ₄ tetrahedron are 4, 5, 6, 8,
4-membered ring, 5-membered ring formed by connecting 10 or 12 pieces,
The basic unit is a double ring in which a 6-membered ring, 8-membered ring, 10-membered ring, or 12-membered ring and each of these 4-, 5-, 6-, 8-, 10-, and 12-membered rings overlap, and these are connected to form a It is known that the skeletal structure of crystalline aluminosilicates can be determined. A specific cavity exists inside the skeleton structure determined by these connection methods, and the entrance of the cavity structure forms an opening consisting of 6-, 8-, 10-, and 12-membered rings. The pores formed have uniform pore diameters, and only molecules of a certain size or less are adsorbed, and large molecules are not adsorbed because they cannot enter the cavities. Such crystalline aluminosilicates are known as "molecular sieves" due to their properties, and are used as adsorbents, catalysts for chemical reactions, or catalyst supports in various chemical processes. In recent years, methods that combine the above molecular sieve action and catalytic action have been intensively researched in various fields of chemical reactions. This is what is called a molecular shape selective reaction catalyst, and SM
As Csicsery categorizes them from a functional perspective, (1) only specific reactants can approach the active site, and (2) only reactants with a specific shape react after reacting at the active site. (3) In a bimolecular reaction, individual molecules can freely move in and out of the reaction field, but cannot react because the transition state is too large. (“Zeolite Chemistry
and Catalysis” ACS Monograph 171, ACS,
Washington DC 1976, p. 680). This classification was made considering only the catalytic reactions inside the cavities of the crystalline aluminosilicate. In other words, catalytic reactions on the outer surface of the crystal or on active sites near the outer surface are different from the above-mentioned catalytic action, and since all reactions occur freely, including reactions with small activation energy, the selectivity of the reaction is reduced. . Therefore, in order to suppress such non-selective reactions on or near the outer surface of the crystal, there is a method of burying the active points by coating the outer surface of the crystal with a compound, or a method of burying the active points by coating the outer surface of the crystal with a compound, or using another method of solid acidity or alkalinity. A method of controlling the solid acidity of the active site has been considered, and the addition of silicon compounds, phosphorus compounds, magnesium compounds, etc. has been proposed. On the other hand, there is also a method of controlling the ratio of the number of active sites with molecular shape selectivity within the crystal to the number of active sites without shape selectivity on or near the outer surface of the crystal by controlling the size of the crystal. It is being For example, when a crystal is made larger, the proportion of active sites within the crystal increases relatively, and shape selectivity becomes higher. However, according to this method, the overall reaction activity is lowered as a result of the relatively limited access of the reactants to the active sites and/or the catalyst. On the other hand, if the crystal is made smaller, the proportion of active sites on or near the outer surface of the crystal increases, resulting in a decrease in shape selectivity. The reaction activity increases as the reaction activity increases. The charge on the AlO ₄ tetrahedron of crystalline aluminosilicate is
Equilibrium is maintained by retaining cations within the crystal. It is a well-known theory that these cations are ion-exchanged by various methods to become a hydrogen type or a metal ion exchange type and function as a solid acid catalyst. In natural crystalline aluminosilicates, the cation is a group of the periodic table of elements or a metal of group of the same table,
In particular sodium, potassium, calcium, magnesium and strontium. The above metal ions are also used in synthetic crystalline aluminosilicates, but in addition to metal ions, organic nitrogen ions, such as quaternary alkylammonium ions such as tetraalkylammonium ions, have recently been proposed. There is. For the synthesis of crystalline aluminosilicate with a high silica/alumina ratio, it has been considered essential to use the above-mentioned nitrogen-containing organic compounds as an alkali source. However, when using nitrogen-containing organic compounds, in addition to the disadvantage of high raw material prices,
In order to use the produced synthetic aluminosilicate as a catalyst, it is necessary to remove the nitrogen-containing organic compounds present in the compound by calcination at high temperature, which has the disadvantage of complicating the production process. It was hot. Furthermore, in the conventional manufacturing method using an amine-based organic compound such as a tetraalkylammonium compound or a C ₂ -C ₁₀ primary amine, etc., as described above, the above-mentioned Various risks have arisen due to the potential toxicity of organic compounds or the decomposition of the organic compounds, posing problems in terms of work safety. Further, the use of oxygen-containing organic compounds, sulfur-containing organic compounds, etc. has also been proposed, but these cases do not solve the problems encountered when using nitrogen-containing organic compounds. As a method for solving these problems, a method has recently been disclosed for producing crystalline aluminosilicate from an aqueous reaction mixture consisting essentially only of inorganic reaction materials (Japanese Patent Application Laid-open No. 45111/1983). It is expressed as the molar ratio of oxide, and is 0.8~
1.5M ₂ /nO・Al ₂ O ₃・10 to 100 SiO ₂・ZH ₂ O (where M is an ion for metal, n is the valence of the metal cation, and Z is 0 to 40 )
Powder X having a chemical composition of
The present invention relates to a crystalline aluminosilicate having a line diffraction pattern. First surface lattice spacing d(A) relative intensity (I/I ₀ ) 11.2±0.2 S. 10.1±0.2 S. 7.5±0.15 W. 6.03±0.1 M. 4.26±0.07 M. 3.86±0.05 VS 3.82±0.05 S. 3.76±0.05 S. 3.72±0.05 S. 3.64±0.05 S. The aluminosilicate having a crystal structure characterized by an X-ray diffraction pattern as described above was named TSZ. In terms of relative strength in Table 1, "VS" is the strongest,
"S." is strong, "M." is medium-strong, "W." is weak, "VW"
indicates that it is very weak. In addition, analysis of particularly accurate 2θ (θ is Bragg angle) measurement results by powder X-ray diffraction analysis, which is different from the conventional method, revealed that the crystalline aluminosilicate (TSZ) according to the invention is crystallographically simple. It is concluded that it belongs to the orthoclic system. In this case, in the aqueous reaction mixture
It is also possible to control the crystal grain size by controlling the SiO ₂ /Al ₂ O ₃ ratio and the NaO ₂ /SiO ₂ ratio (Japanese Patent Application Nos. 58-30797 and 58-46684). On the other hand, when zeolite catalysts are used industrially, for example in fixed beds of gaseous and liquid feedstocks or in fluidized bed operations such as catalytic cracking, they are formed into particles with a certain shape, e.g. Supplied in particles, small spherical particles. In this case, the gas phase reaction is generally carried out at a large space velocity, and in the liquid phase reaction of heavy oil, diffusion from the catalyst surface is limited, so almost only the outer surface of the catalyst particles is used (in the US Patent No. 3,966,644 shows that this diffusion limit is about 1/120 inch)
Therefore, it is desirable to increase the surface area of the active zeolite catalyst as much as possible. This problem can be improved by reducing the diameter of the spherical catalyst particles, but this also reduces the strength of the catalyst particles and causes their destruction. There are limits to things. It can also be improved by reducing the particle size of the zeolite crystal powder, but on the other hand,
Shaped catalyst particles made only of zeolite crystal powder have the disadvantage that they cannot maintain sufficient strength to withstand industrial use. Therefore, conventionally, when zeolite catalysts were used industrially, powdered zeolite was molded into, for example, pellets using a suitable binder. However, according to this method, not only is a decrease in productivity unavoidable, such as a decrease in the utilization rate of the zeolite used, which necessitates a decrease in the space velocity of the reactants, but also This method has the disadvantage that the zeolite is easily poisoned as a result of the migration of alkali or alkaline earth metals into the zeolite. In addition, since the method for producing pellet-type catalysts involves compressing and molding zeolite and an amorphous binder, the amorphous binder is trapped in the so-called secondary pores that exist between the zeolite crystals. Although the physical strength increased due to the penetration, neither the amount nor the distribution of secondary pores could be controlled. <<Problems to be Solved by the Invention>> Secondary pores mainly occur between particles when amorphous powder or crystalline powder is molded, so it is possible to eliminate these pores without reducing the strength of the pellet. If the pores can be utilized, the catalytic activity of the pellet can be improved by not only allowing the reactants to move easily from crystal to crystal, but also by substantially increasing the area of catalytically active crystal surfaces. The inventors of the present invention and others
(filed on March 9th) to resolve these issues,
We have provided a binderless catalyst body with a unique shape that takes advantage of secondary pores (contains TSZ zeolite) and has excellent catalytic activity, and a method for producing the same. However, the crystals obtained by this method are relatively large, and the presence of a sodium salt in the hydrothermal reaction solution is essential. The manufacturing method is not specified. Therefore, the first object of the present invention is to provide a method for producing a binderless zeolite catalyst consisting essentially of crystalline aluminosilicate in which secondary pores are utilized, without using a mineralizing agent. It is to be. A second object of the present invention is to provide a method for easily producing a binderless zeolite catalyst consisting essentially of crystalline aluminosilicate, which is composed of small crystal particles and has sufficient strength. . Furthermore, a third object of the present invention is to provide a method for preparing an aluminosilicate gel suitable for easily synthesizing binderless zeolite without using a mineralizing agent. B. Structure of the Invention <<Means for Solving the Problem>> That is, the present invention is directed to producing substantially crystalline aluminosilicate from a molded product obtained by kneading raw material powder and aluminosilicate gel as a binder and press-molding the mixture. In the method for producing a binder-free crystalline aluminosilicate consisting of: The present invention provides a method for producing a crystalline aluminosilicate and a method for preparing an aluminosilicate gel. ≪Disclosure of the Invention≫ The binderless zeolite catalyst of the present invention consisting essentially of crystalline aluminosilicate includes the binderless zeolite catalyst described above, but the binderless zeolite catalyst of the present invention is particularly suitable for the mercury intrusion method. The total pore solution measured by
cc/g or more, the pore radius is 75 to 75,000 Å, 25% or more of the pore volume is included in the range of ±20% of the average pore diameter of the radius, and is composed of relatively small crystal particles. It is characterized by giving an X-ray diffraction pattern of substantially TSZ crystalline aluminosilicate. In general, the strength of shaped particles varies depending on the size of the constituent particles, the packing structure, the coordination number of the particles, the shape of the particles, etc., and further varies depending on the volume and radius of the pores formed. In particular, shaped zeolite catalysts are aggregates of crystal particles with various shapes, and the pore structure is a so-called binary pore structure, consisting of micropores possessed by the crystal particles themselves and macropores formed between the crystal particles. Ru. However, such crystal grains usually have little bonding strength, and are molded using some kind of binder to give the pellet strength. From the above, it can be seen that the binderless zeolite of the present invention, which consists essentially of crystalline aluminosilicate, has a sharp distribution of macropores of several thousand Å, and a pore volume (75 to 75,000 Å, radius) that is comparable to that of the present invention. It is truly surprising that it is strong enough to withstand practical use, despite its high strength. The outline of the manufacturing process of the binderless zeolite catalyst according to the present invention is as follows: Step of manufacturing raw material powder Step of manufacturing aluminosilicate gel for binder Step of kneading and molding raw material powder and binder Drying of molded product or a step of firing, a step of hydrothermally treating the molded product, and other steps. The raw material powder used in the present invention means a pre-synthesized crystalline aluminosilicate. As such a preferable pre-synthesized crystalline aluminosilicate used as a raw material powder, TSZ
Aluminosilicates and so-called ZSM-5 can be used. The pre-synthesized crystalline aluminosilicate used here suffices in the unfired, as-synthesized form; furthermore, it does not need to be in a perfect crystalline form; it may simply be pre-crystallized, and it may not be in the form of a complete crystal. It is also possible to use an aluminosilicate that exhibits an X-ray diffraction pattern close to that of a crystalline substance, but especially when TSZ crystalline aluminosilicate is used, a binderless zeolite rich in TSZ crystalline aluminosilicate cannot be produced. It is preferable. If zeolites other than TSZ crystalline aluminosilicate are used, they are preferably used in particular in the form of their sodium salts. Regarding the composition of the above raw material powder, SiO ₂ /
It is preferable that the Al ₂ O ₃ ratio and the Na ₂ O/SiO ₂ ratio are in the TSZ generation range described below, and that the crystals have a small particle size, which improves the activity and strength of the binderless zeolite produced. Preferable from this point of view. Furthermore, in the production of raw material powder, a mineralizing agent such as NaCl may be added for the purpose of improving the fluidity of the gel. The TSZ crystalline aluminosilicate according to the present invention is
It is characterized by an X-ray diffraction pattern obtained by conventional powder X-ray diffraction. That is, 2θ=14.7° (d
= 6.03 Å) is a single line, and 2θ = 23° (d = 3.86 Å) and 2θ = 23.3°
(d = 3.82 Å) in that the two diffraction lines are clearly separated, which is significantly different from the crystal structure of the crystalline zeolite proposed previously. Such a specific X-ray diffraction pattern is caused by changes in the lattice spacing due to changes in the substituted cations of the synthetic silicate, especially changes to the hydrogen ion type, changes in the SiO ₂ /Al ₂ O ₃ ratio, etc. It is not subject to change. Next, a method for producing crystalline aluminosilicate as a raw material powder used in the present invention will be explained. The crystalline aluminosilicate that can be used in the present invention generally uses SiO ₂ as a silicon source, Al ₂ O ₃ as an aluminum source in a certain range of ratios, and a suitable alkali source and water in a certain range of ratios. It can be prepared by preparing an aqueous reaction mixture consisting of substantially inorganic reactant materials added to the reaction mixture and maintaining the aqueous reaction mixture heated to the crystallization temperature until crystals form. The manufacturing conditions are, for example, about 120°C to about 230°C under self-pressure for about 10 hours to 10
This is achieved by maintaining it for several days. TSZ crystalline aluminosilicate is produced from an aqueous reaction mixture consisting of substantially inorganic reactants containing a silica source, an alumina source, an alkali source, water and a neutral salt of an alkali metal; The composition expressed in molar ratio of oxides is as follows. SiO ₂ /Al ₂ O ₃ 10-130 Na ₂ O / SiO ₂ 0.01-0.5 (Na ₂ O + M ₂ /nO) / SiO ₂ 0.03-0.3 H ₂ O / (Na ₂ O + M ₂ /nO) 150-800 X ^- /SiO ₂ 0.01-20 In the above formula, M is a metal cation selected from Groups and Groups of the Periodic Table of the Elements, preferably lithium, sodium, barium, calcium and strontium, and n is the metal cation , and X ^- is the ion of the salt of the precipitation aid and/or mineralizing agent. M ₂ /nO and Na ₂ O are free M ₂ /nO and Na ₂ O, respectively, and are generally in the form of very weak acid salts, such as aluminates, silicates, etc., which are effective in hydroxide and zeolite synthesis. It is. Also, the above “free Na ₂ O” is
It can be adjusted by adding aluminum sulfate, sulfuric acid, hydrochloric acid, nitric acid, etc. In addition, TSZ crystalline aluminosilicate can be produced by changing the composition ratio of the aqueous reaction mixture, especially the SiO ₂ /Al ₂ O ₃ 3 molar ratio and the Na ₂ O /SiO ₂ molar ratio. The grain size of the aluminosilicate changes. i.e. SiO ₂ / of the aqueous reaction mixture
After changing _the Na ₂ O / SiO ₂ molar ratio according to the Al ₂ O 3 3 molar ratio so that the Na ₂ O / Al ₂ O ₃ 3 molar ratio is equal, SiO ₂ /Al ₂ O ₃ 3 When the molar ratio is changed, crystalline aluminosilicate having approximately the same crystal grain size is produced. In contrast, Na ₂ O/
By varying the Al ₂ O ₃ molar ratio in the range of 1 to 15, crystalline aluminosilicate having a desired crystal grain size in the range of about 0.1 μ to 10 μ can be produced. In the synthesis of the binderless zeolite of the present invention, when using the conventional method as described above,
It is preferable to add a neutral salt of an alkali metal that acts as a so-called mineralizing agent during the production of aluminosilicate gel because it also acts as a precipitation aid to improve the fluidity of aluminosilicate gel. In a preferred embodiment of the invention, the fluidity of the aluminosilicate gel is made good by selecting a specific composition, and in particular, crystallinity equivalent to that obtained by adding a mineralizing agent is obtained without adding a neutral salt of an alkali metal. An object of the present invention is to produce a crystalline aluminosilicate having a small particle size that is suitable for the purpose of catalytic activity. The gel with good fluidity used in the present invention has a pH range (depending on the composition ratio of the aqueous reaction mixture) where gel aggregation (in the case of alkaline side) occurs rapidly.
It can be prepared by once stopping the addition of the solution at about 11.0 to about 12.0), and adding the solution again after stirring improves the fluidity of the slurry-like gel. Even in the case of the present invention in which no mineralizing agent is used,
TSZ crystalline aluminosilicate is produced from an aqueous mixture of substantially inorganic reactants containing a silica source, an alumina source, an alkali source, and water, where the aqueous reaction mixture is expressed in molar ratios of oxides. The preferred range is _SiO2 / _{Al2O3 10-100 Na2O} / _SiO2 0.01-0.5 _H2O / _SiO2 5-150, and the more preferred range is _SiO2 / _{Al2O3 25-150} . 80 _Na2O / _SiO2 0.02-0.2 _H2O / _SiO2 10-130. The above Na ₂ O is "free Na ₂ O" and is generally in the form of very weak acids such as aluminates, silicates, etc., which are effective in hydroxide and zeolite synthesis. Also, the above “free Na ₂ O” is
It can be adjusted by adding aluminum sulfate, sulfuric acid, hydrochloric acid, nitric acid, etc. In addition, among the composition ratios, if the Na ₂ O / SiO ₂ ratio is low, relatively small crystals are likely to be generated, and Na ₂ O / SiO ₂
Similar to the case of mineralizing agent addition, when the ratio is high, relatively large crystals tend to be generated. In particular, in order to produce the raw material powder for producing the binderless zeolite catalyst that is composed of relatively small crystal particles and has high strength in the present invention, it is necessary to use powder containing a silica source, an alumina source, an alkali source, and water. The aqueous mixture consisting essentially of inorganic reactive materials, expressed in molar ratio of oxides, has a preferred range of _Na2O / _{Al2O3 1.0-10 SiO2} / _{Al2O3 15-100 Na2O} / _SiO2 0.01-0.15 _H2O / _SiO2 5-150, and a more preferable range is _Na2O / _{Al2O3 1.5-8 SiO2} / _{Al2O3 20-80 Na2O} / _SiO2 0.02-0.12 _H2O / _SiO2 10-130. FIG. 1 illustrates the above range. The raw material powder obtained here may be crystalline, a mixture of crystalline and amorphous, or amorphous. If the amount of alkali is less than the above range, it will take a long time for crystallization, but if it is even less, the effect as a pretreatment may be lost. Furthermore, if the amount of alkali is greater than the above range, the crystallization time can be shortened, but this is not preferable because the crystal particles produced become too large or different crystal phases are produced. The aluminosilicate gel used as a binder in the present invention is prepared from an aqueous reaction mixture consisting of substantially inorganic reaction materials containing a silica source, an alumina source, an alkali source and water, the preferred composition of the aqueous reaction mixture being When expressed as the molar ratio of oxides, the preferred range is: Na ₂ O/Al ₂ O ₃ 1.2-10 SiO ₂ /Al ₂ O ₃ 10-100 Na ₂ O/SiO ₂ 0.01-0.20 H ₂ O/SiO ₂ 5-150, and the more preferable range is _Na2O / _{Al2O3 1.5-8 SiO2} / _{Al2O3 15-80 Na2O} / _SiO2 0.02-0.15 _H2O /SiO2 _10-130 It is. The above Na ₂ O is free Na ₂ O, and is generally in the form of very weak acid salts, such as aluminates and silicates, which are effective in the synthesis of hydroxides and zeolites. Moreover, the above-mentioned "free Na ₂ O" can be adjusted by adding aluminum sulfate, sulfuric acid, hydrochloric acid, nitric acid, or the like. When the aluminosilicate gel produced here is used as a binder, it is preferable to filter the produced gel, wash it to a desired composition, drain it, and bring the water content from about 65% to about 95% by weight. . The amount of alkali in the binder is an important factor for producing binderless zeolite.
In other words, if the amount of alkali is small, it may take a long time to crystallize or remain amorphous, and if the amount of alkali is large, large crystals may be formed due to excessive crystal growth. However, it is preferable to keep the composition within a specific range. Another important element as a binder is
The strength imparted to the molded pellets is strongly influenced by the tackiness, moldability, dry shrinkage force, etc. of the aluminosilicate gel. Therefore, it is preferable to form colloidal particles with good dispersibility when preparing aluminosilicate gel, and if necessary, a small amount of a neutral salt of an alkali metal can be added as a precipitation aid, but stirring, post-treatment, etc. It is preferable not to add it unless there is a problem in handling the gel. In the present invention, the composition of the aluminosilicate gel (on a dry basis) used as a binder for producing a binderless zeolite catalyst with relatively small crystal particles and high strength is preferably as follows when expressed in molar ratio of oxides: The composition is _Na2O / _{Al2O3 1.2-7.0 SiO2} / _{Al2O3 10-80 Na2O} /SiO2 _0.02-0.15 , and a more preferable composition is _Na2O / _{Al2O3 1.5} -4.0 _{SiO2 / Al2O3} 15-60 _Na2O / _SiO2 0.03-0.12. FIG. 2 shows the composition range of the above binder. In the present invention, produced as described above,
Raw material powder such as TSZ crystalline aluminosilicate and aluminosilicate gel are kneaded and formed into pellets. In this case, an aluminosilicate gel containing 30 to 70% by weight of pre-synthesized crystalline aluminosilicate as a raw material powder and an alkali content of 70 to 70% by weight is used.
By kneading and molding 30% by weight, strong pellets can be obtained. Next, the obtained pellets are hydrothermally treated to produce a binder consisting essentially of crystalline aluminosilicate, which has unique secondary pores formed between crystal grains and maintains sufficient strength for practical use. When the mixing ratio of the crystalline aluminosilicate is less than about 30% by weight, the strength of the pellets tends to increase, but shrinkage of the pellets due to drying or calcination and associated cracks occur. It is difficult to obtain stable physical properties such as, etc., and if the mixing ratio of crystalline aluminosilicate as the raw material powder is more than about 70% by weight, sufficient pellet strength cannot be obtained, which is not preferable. In addition, the composition of the pre-synthesized crystalline aluminosilicate and the composition of the aluminosilicate gel used as a binder may be different, but if they are made almost the same, the catalyst This is preferable because a binderless zeolite with good performance can be obtained. When molding the above-mentioned kneaded material into pellets, a molding aid may be used. The molding aid can be arbitrarily selected from known ones used in ordinary extrusion molding, but
In particular, organic materials that are burnt out in post-treatment are preferred. However, in consideration of the final strength of the pellets, it is preferable that the addition of molding aids be kept to the minimum necessary or not added at all. If there is an excess or deficiency in the amount of alkali in the aluminosilicate gel, it can be adjusted to a predetermined value before or during kneading. The molded pellets are thoroughly air-dried under conditions that prevent distortion due to drying shrinkage or the like as much as possible, for example, and then heated at 50 to 200°C, preferably 100 to 150°C. If the pellets after drying have sufficient strength, there is no need for calcination, but if not, or if a molding aid is used, it is preferable to calcinate at 400 to 700°C, preferably 450 to 600°C. Binderless zeolite can be produced by hydrothermal treatment even in a dry state and after calcination. The shape of the solid used in the hydrothermal reaction in the present invention is not particularly limited, but from the viewpoint of ease of molding or usage efficiency when used as a catalyst, pellet type, polylobal type,
It is preferable to have a hollow cylindrical shape, and the size should be around the outside diameter from the viewpoint of handling.
A thickness of about 1.5 mm is preferable. The hydrothermal reaction of the present invention can be carried out by a known method, but as a crystalline aluminosilicate,
If something other than the TSZ crystalline aluminosilicate is used, it is particularly preferred to use a mineralizer or a cation source, and NaCl is particularly preferred as such. Conditions for crystallization are not particularly limited, as long as heating is maintained at the crystallization temperature until crystals are formed. For example, at a temperature of about 120°C to 230°C, the reaction time is about 10 hours to about 10 days. Preferred crystallization conditions depend on the composition ratio of the dried or calcined pellets and the weight ratio of the aqueous solution to the pellets, but in general, the higher the temperature, the shorter the time, and the lower the temperature, the longer the time required. . However, it is not preferable to use an excessively low temperature range or an excessively high temperature because it may become amorphous or produce undesired crystals. When hydrothermally treating pellets, stirring is not particularly necessary, but it is preferable to at least stir the pellets in order to uniformly heat the entire system. The aqueous solution used in the present invention may be water alone since the pellet itself is adjusted in advance to a composition ratio that allows crystallization, but a mineralizing agent may be used to speed up the crystallization rate or shorten the time. I can do it. In particular, this selection is preferably determined from the viewpoint of the degree of growth of crystal particles, physical properties thereof, or catalytic performance. The pellets are placed with water or an aqueous solution in a closed container, such as an autoclave made of iron, stainless steel or lined with Teflon, and allowed to crystallize under autogenous pressure. The binderless zeolite thus obtained consists essentially of crystalline aluminosilicate.
It is washed with water, dried, and can be post-treated as is, but it may be fired if necessary.
Drying is carried out at 50 to 250°C, preferably 100 to 200°C, for 10 minutes or more, preferably 30 minutes to 48 hours. Firing is
At 300-700℃ for 10 minutes or more, preferably at 400-600℃
It is held for 30 minutes to 24 hours. As a result of the hydrothermal treatment carried out in the present invention, the binder crystallizes into a crystalline aluminosilicate. Therefore,
When using an aluminosilicate gel with a formation region that produces TSZ crystalline aluminosilicate as a binder, X-ray diffraction of TSZ crystalline aluminosilicate shows the characteristics when synthesized without using organic cations. The distribution of secondary pores is extremely sharp. Although a method for measuring the radius of the secondary pores to be controlled in the present invention is not necessarily established, the average radius can be estimated by the so-called mercury intrusion method.
In the present invention, the average pore radius is defined as the radius that indicates the cumulative pore volume of 1/2 of the total pore volume obtained by this mercury intrusion method, but the size of this pore radius is substantially Not only is it related to the catalyst surface area;
It is important from the viewpoint of catalytic activity, as it also affects the diffusion rate of reacting molecules and generated molecules. The binderless zeolite obtained by the present invention has good overall crystallinity. For example, when TSZ crystalline aluminosilicate is used as the starting zeolite, the TSZ crystalline aluminosilicate formed by crystallization of the binder Silicates and starting materials TSZ
It is possible to obtain a zeolite structure that is so integrated that it cannot be distinguished from crystalline aluminosilicate in a micrograph. Substantially TSZ obtained by the method of the present invention
Binderless zeolite pellets made of crystalline aluminosilicate undergo several further treatments depending on the purpose of use, but unlike powder, they undergo subsequent washing, conversion to hydrogen form, ion exchange operations for active metal species, etc. It becomes extremely easy to handle. When used as a catalyst, zeolite is generally ion-exchanged with an aqueous solution containing ammonium ions, hydrogen ions, or divalent or trivalent metal cations, such as rare earth metal ions, to impart solid acidity to the zeolite. It exhibits extremely high catalytic activity for many reactions with solid acidity, such as isomerization, disproportionation, alkylation, dealkylation, decomposition, reforming, polymerization, and hydrogenolysis. After ion exchange treatment, it is washed with water, dried, and fired prior to further use. In addition to ion exchange, components such as iron, cobalt, nickel, chromium, manganese, molybdenum, tungsten, vanadium, rhenium, platinum, rhodium, ruthenium, and palladium can also be supported by impregnation. <<Effects of the Invention>> The binderless zeolite of the present invention thus obtained not only has excellent activity due to its small crystal particle size and the control of secondary pores, but also has the ability to maintain activity. In particular, it has excellent performance as a catalyst for selective decomposition of n-paraffinic hydrocarbons and aromatic alkylation reactions using alkylating agents such as alcohols and olefins. Moreover, according to the method of the present invention, mineralizing agents and
Since there is no need to use NaOH, there is no need to worry about corrosion of the reactor, and the present invention has great significance. EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto. <<Example>> Example 1 24.0g of aluminum sulfate (Al ₂ O ₃ ; 15.4% by weight) was dissolved in 194.8g of pure water, and 25.3g of concentrated sulfuric acid (95% by weight) was added thereto. An aluminum aqueous solution (liquid A) was prepared. 280.8g water glass (Na ₂ O; 9.36% by weight,
142.0 g of pure water was added to No. 3 water glass (SiO ₂ ; 29.4% by weight), stirred, and then added to an aqueous sodium chloride solution (NaCl; 86.2 g, H ₂ O; 556.1 g).
A water glass solution (liquid B) was prepared. This was placed in an autoclave, heated, and maintained at 182°C under autogenous pressure for 20 hours. After the crystallization was completed, the solid product was separated by filtration, washed with pure water, and dried at 110°C. 50g of zeolite powder and aluminosilicate gel obtained in this way
Knead 370.4g with a kneader while drying until the moisture content can be molded, and then use an extrusion molding machine to reduce the outer diameter to approx.
It was molded into 1.5mm pellets. The aluminosilicate gel used here consisted of 44.3 g of aluminum sulfate, 43.5 g of 95% sulfuric acid, and pure water.
389.6g of aluminum sulfate aqueous solution, 561.6g of water glass (No. 3 water glass), 284.0g of pure water, 53.7g of sodium chloride, 1112g of pure water
Add to the solution dissolved in the solution, prepare, filter and wash,
Drain thoroughly. The composition ratio of this aluminosilicate gel is shown in Table 1. After drying the pellets at about 110℃ for 16 hours,
After calcining at 600℃ for about 3 hours, take out 50g, put it in an autoclave with 350g of pure water, and heat it at 180℃ for 48 hours.
Time crystallization was performed. The results are shown in Table 2. Example 2 The same procedure as in Example 1 was carried out except that the amounts of sulfuric acid and pure water added were different and that sodium chloride was not added. The crystallization was performed at 183°C for 40 hours, and a zeolite powder with good crystallinity equivalent to that obtained when sodium chloride was added was obtained. 50 g of the raw material fraction thus obtained and 370.4 g of the aluminosilicate gel produced in Example 1 were kneaded in a kneader while drying until the moisture content reached a moldable level, and molded into pellets with an outer diameter of approximately 1.5 mm using an extruder. . After drying the pellets at about 110℃ for 16 hours,
After calcining at 600°C for about 3 hours, 50g was taken out and placed in an autoclave with 690g of pure water and 25g of sodium chloride, and crystallized at 180°C for 40 hours. The results are shown in Table 2.

【table】

[Table] Example 3 29.6 g of aluminum sulfate was dissolved in 194.8 g of pure water, and 24.1 g of 95% sulfuric acid was added thereto to prepare an aluminum sulfate aqueous solution (liquid A). Add 142.0g of pure water to 280.8g of water glass,
A water glass solution (liquid B) was prepared. These A and B solutions were added to an aqueous sodium chloride solution (NaCl; 72.2 g, H ₂ O 556.1 g) with stirring to obtain an aqueous reaction mixture shown in Table 1. This was placed in an autoclave and heated to 182°C under autogenous pressure.
Heating was maintained for 24 hours. After the crystallization was completed, the solid product was separated by filtration, washed with pure water, and dried at 110°C. 50g of powder thus obtained and 414g of aluminosilicate gel
The mixture was kneaded with a kneader while drying until the moisture content reached a moldable level, and molded into pellets with an outer diameter of approximately 1.5 mm using an extruder. The aluminosilicate gel used here consisted of 29.6 g of aluminum sulfate, 18.3 g of 95% sulfuric acid, and pure water.
194.8g of aluminum sulfate aqueous solution and water glass
280.8 g of pure water was added to a water glass aqueous solution of 700.0 g to prepare, and after filtering and washing, the water was thoroughly drained. The composition ratio of this aluminosilicate gel is shown in Table 1. After drying the pellets at about 110℃ for 16 hours,
After calcining at 600°C for about 3 hours, 50g was taken out, placed in an autoclave with 690g of pure water and 24.2g of sodium chloride, and crystallized at 180°C for 40 hours.
The results are shown in Table 2. Example 4 8.3g of sodium aluminate (Al ₂ O ₃ ; 35.7% by weight, Na _2O ; 29.1% by weight) was dissolved in 292.5g of pure water, and this was mixed with 273.8g of water glass and 135.7g of pure water. Add to the water glass solution to make a homogeneous solution. A hydrochloric acid solution of this, 58.3 g of 35% hydrochloric acid, and 175.5 g of pure water was added to 1100 g of pure water to obtain the aqueous reaction mixture shown in Table 3. Put this in an autoclave
The temperature was raised and maintained at 182° C. for 24 hours at autogenous pressure. Stirring was performed at 300 rpm. After the crystallization was completed, the solid product was separated by filtration, washed with pure water, and dried at 110° C. for 16 hours. 50 g of the thus obtained zeolite powder and 365 g of aluminosilicate gel were kneaded in a kneader while drying until the moisture content reached a moldable level, and molded into pellets with an outer diameter of about 1.5 mm using an extruder. The aluminosilicate used here was prepared in the same manner as in Example 1. This composition ratio is shown in Table 3. After drying the pellets at about 110℃ for 16 hours, 50g
The sample was collected, placed in an autoclave with 350 g of pure water, and heated and maintained at 180°C for 48 hours. The results are shown in Table 4. Comparative Example 17.7 g of aluminum sulfate was dissolved in 194.8 g of pure water, and 15.6 g of 95% sulfuric acid was added thereto to prepare an aluminum sulfate aqueous solution (liquid A).

【table】

【table】

[Table] Add 142.0g of pure water to 280.8g of water glass,
A water glass solution (solution B) was prepared. These A and B solutions were added to an aqueous sodium chloride solution (NaCl; 86.2 g, H ₂ O 556.1 g) with stirring to obtain an aqueous reaction mixture having the composition ratio shown in Table 3. This was placed in an autoclave and heated and maintained at 180°C for 18 hours under autogenous pressure. After the crystallization was completed, the solid product was separated by filtration, washed with pure water, and dried at 110°C. 50g of the zeolite powder and 360g of aluminosilicate gel obtained in this way were kneaded in a kneader while drying until the moisture content reached a moldable level, and then an extruder was used to mold the zeolite powder with an outer diameter of approx.
It was molded into 1.5mm pellets. The aluminosilicate gel used here consisted of 14.8 g of aluminum sulfate, 22.5 g of 95% sulfuric acid, and pure water.
194.8g of aluminum sulfate aqueous solution and water glass
A water glass aqueous solution containing 280.8 g of pure water and 142.0 g of pure water was added to a solution in which 26.8 g of sodium chloride was dissolved in 556.1 g of pure water, stirred, and thoroughly drained after filtration and washing. The composition ratio of this aluminosilicate gel is shown in Table 3. After drying the pellets at about 110℃ for 16 hours,
After calcining at 600°C for about 3 hours, 50g was taken out, placed in an autoclave with 690g of pure water and 27.6g of NaCl, and crystallized at 180°C for 20 hours. The crystals are shown in Table 4, and the constituent crystal particles were relatively large and weak in strength. These results demonstrate that the binderless zeolite obtained by the present invention has sufficient strength for practical use despite its small particle size.

[Brief explanation of the drawing]

FIG. 1 is a graph showing a preferred range of the composition ratio of the aqueous reaction mixture of the raw material powder used in the present invention. The inner ranges represent particularly preferred ranges. The numbers in the figure represent the molar ratio of Na ₂ O/Al ₂ O ₃ . FIG. 2 is a graph showing the preferred range of the binder composition ratio used in the present invention. The inner ranges represent particularly preferred ranges. The numbers in the figure are Na ₂ O/Al ₂ O ₃
represents the molar ratio of

Claims (1)

[Scope of Claims] 1. Crystalline aluminosilicate without a binder consisting essentially only of crystalline aluminosilicate from a molded product obtained by kneading raw material powder and aluminosilicate gel as a binder and molding under pressure. In the method of manufacturing salt, the amount of raw material powder used is 30~
70% by weight, and the amount of aluminosilicate gel used as a binder is 70 to 30% by weight. 2. The composition ratio of the aqueous reaction mixture during the production of raw material powder, expressed as the molar ratio of oxides, is M ₂ /nO/Al ₂ O ₃ : 1.0 to 10 SiO ₂ /Al ₂ O ₃ : 15 to 100 M ₂ /nO/ _SiO2 : 0.01 to 0.15 _H2O /SiO2 ₅ to 150 (However, M is at least one metal cation selected from the group of metals in Group 1 of the Periodic Table of the Elements and Group 1 of the same table. and n is the valence of the metal cation.) The method for producing a crystalline aluminosilicate according to claim 1. 3 The composition ratio of the aqueous reaction mixture during raw material powder production, expressed as the molar ratio of oxides, is M ₂ /nO/Al ₂ O ₃ : 1.5 to 8 SiO ₂ /Al ₂ O ₃ : 20 to 80 M ₂ /nO/ _SiO2 : 0.02-0.12 _H2O / _SiO2 10-130 The method for producing a crystalline aluminosilicate according to claim 2. 4 The composition ratio of the aluminosilicate gel used as a binder, expressed as the molar ratio of oxides, is M ₂ /nO / Al ₂ O ₃ : 1.2 to 7.0 SiO ₂ /Al ₂ O ₃ : 10 to 80 M ₂ /nO / _SiO2 : 0.02 to 0.15 (However, M is at least one metal cation selected from the group of metals in Group 1 of the Periodic Table of the Elements and Group 1 of the same table, and n is the valence of the metal cation. ) The method for producing a crystalline aluminosilicate according to claim 1. 5 The composition ratio of the aluminosilicate gel used as a binder, expressed as the molar ratio of oxides, is M ₂ /nO / Al ₂ O ₃ : 1.5 to 4.0 SiO ₂ /Al ₂ O ₃ : 15 to 60 M ₂ /nO / _SiO2 : 0.03 to 0.12, the method for producing a crystalline aluminosilicate according to claim 4. 6. For producing a binder-free crystalline aluminosilicate consisting essentially only of crystalline aluminosilicate from a molded product obtained by kneading raw material powder and aluminosilicate gel as a binder and press-molding the mixture. In the preparation method of aluminosilicate gel, when mixing the silica source, alumina source, and alkali source, the pH at which gel agglomeration occurs rapidly is
A method for preparing an aluminosilicate gel, which is characterized in that the addition of the solution is stopped once at a certain temperature, and the fluidity of the slurry gel is improved by stirring, and then the solution is added again.